1 /*
2 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "jvm_bsd.h"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/filemap.hpp"
36 #include "mutex_bsd.inline.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "os_share_bsd.hpp"
39 #include "prims/jniFastGetField.hpp"
40 #include "prims/jvm.h"
41 #include "prims/jvm_misc.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/extendedPC.hpp"
44 #include "runtime/globals.hpp"
45 #include "runtime/interfaceSupport.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/javaCalls.hpp"
48 #include "runtime/mutexLocker.hpp"
49 #include "runtime/objectMonitor.hpp"
50 #include "runtime/osThread.hpp"
51 #include "runtime/perfMemory.hpp"
52 #include "runtime/sharedRuntime.hpp"
53 #include "runtime/statSampler.hpp"
54 #include "runtime/stubRoutines.hpp"
55 #include "runtime/threadCritical.hpp"
56 #include "runtime/timer.hpp"
57 #include "services/attachListener.hpp"
58 #include "services/runtimeService.hpp"
59 #include "thread_bsd.inline.hpp"
60 #include "utilities/decoder.hpp"
61 #include "utilities/defaultStream.hpp"
62 #include "utilities/events.hpp"
63 #include "utilities/growableArray.hpp"
64 #include "utilities/vmError.hpp"
65 #ifdef TARGET_ARCH_x86
66 # include "assembler_x86.inline.hpp"
67 # include "nativeInst_x86.hpp"
68 #endif
69 #ifdef TARGET_ARCH_sparc
70 # include "assembler_sparc.inline.hpp"
71 # include "nativeInst_sparc.hpp"
72 #endif
73 #ifdef TARGET_ARCH_zero
74 # include "assembler_zero.inline.hpp"
75 # include "nativeInst_zero.hpp"
76 #endif
77 #ifdef TARGET_ARCH_arm
78 # include "assembler_arm.inline.hpp"
79 # include "nativeInst_arm.hpp"
80 #endif
81 #ifdef TARGET_ARCH_ppc
82 # include "assembler_ppc.inline.hpp"
83 # include "nativeInst_ppc.hpp"
84 #endif
85 #ifdef COMPILER1
86 #include "c1/c1_Runtime1.hpp"
87 #endif
88 #ifdef COMPILER2
89 #include "opto/runtime.hpp"
90 #endif
91
92 // put OS-includes here
93 # include <sys/types.h>
94 # include <sys/mman.h>
95 # include <sys/stat.h>
96 # include <sys/select.h>
97 # include <pthread.h>
98 # include <signal.h>
99 # include <errno.h>
100 # include <dlfcn.h>
101 # include <stdio.h>
102 # include <unistd.h>
103 # include <sys/resource.h>
104 # include <pthread.h>
105 # include <sys/stat.h>
106 # include <sys/time.h>
107 # include <sys/times.h>
108 # include <sys/utsname.h>
109 # include <sys/socket.h>
110 # include <sys/wait.h>
111 # include <time.h>
112 # include <pwd.h>
113 # include <poll.h>
114 # include <semaphore.h>
115 # include <fcntl.h>
116 # include <string.h>
117 #ifdef _ALLBSD_SOURCE
118 # include <sys/param.h>
119 # include <sys/sysctl.h>
120 #else
121 # include <syscall.h>
122 # include <sys/sysinfo.h>
123 # include <gnu/libc-version.h>
124 #endif
125 # include <sys/ipc.h>
126 # include <sys/shm.h>
127 #ifndef __APPLE__
128 # include <link.h>
129 #endif
130 # include <stdint.h>
131 # include <inttypes.h>
132 # include <sys/ioctl.h>
133
134 #if defined(__FreeBSD__) || defined(__NetBSD__)
135 # include <elf.h>
136 #endif
137
138 #ifdef __APPLE__
139 #include <mach/mach.h> // semaphore_* API
140 #include <mach-o/dyld.h>
141 #endif
142
143 #ifndef MAP_ANONYMOUS
144 #define MAP_ANONYMOUS MAP_ANON
145 #endif
146
147 #define MAX_PATH (2 * K)
148
149 // for timer info max values which include all bits
150 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
151 #define SEC_IN_NANOSECS 1000000000LL
152
153 #define LARGEPAGES_BIT (1 << 6)
154 ////////////////////////////////////////////////////////////////////////////////
155 // global variables
156 julong os::Bsd::_physical_memory = 0;
157
158 #ifndef _ALLBSD_SOURCE
159 address os::Bsd::_initial_thread_stack_bottom = NULL;
160 uintptr_t os::Bsd::_initial_thread_stack_size = 0;
161 #endif
162
163 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
164 #ifndef _ALLBSD_SOURCE
165 int (*os::Bsd::_pthread_getcpuclockid)(pthread_t, clockid_t *) = NULL;
166 Mutex* os::Bsd::_createThread_lock = NULL;
167 #endif
168 pthread_t os::Bsd::_main_thread;
169 int os::Bsd::_page_size = -1;
170 #ifndef _ALLBSD_SOURCE
171 bool os::Bsd::_is_floating_stack = false;
172 bool os::Bsd::_is_NPTL = false;
173 bool os::Bsd::_supports_fast_thread_cpu_time = false;
174 const char * os::Bsd::_glibc_version = NULL;
175 const char * os::Bsd::_libpthread_version = NULL;
176 #endif
177
178 static jlong initial_time_count=0;
179
180 static int clock_tics_per_sec = 100;
181
182 // For diagnostics to print a message once. see run_periodic_checks
183 static sigset_t check_signal_done;
184 static bool check_signals = true;;
185
186 static pid_t _initial_pid = 0;
187
188 /* Signal number used to suspend/resume a thread */
189
190 /* do not use any signal number less than SIGSEGV, see 4355769 */
191 static int SR_signum = SIGUSR2;
192 sigset_t SR_sigset;
193
194
195 ////////////////////////////////////////////////////////////////////////////////
196 // utility functions
197
198 static int SR_initialize();
199 static int SR_finalize();
200
201 julong os::available_memory() {
202 return Bsd::available_memory();
203 }
204
205 julong os::Bsd::available_memory() {
206 #ifdef _ALLBSD_SOURCE
207 // XXXBSD: this is just a stopgap implementation
208 return physical_memory() >> 2;
209 #else
210 // values in struct sysinfo are "unsigned long"
211 struct sysinfo si;
212 sysinfo(&si);
213
214 return (julong)si.freeram * si.mem_unit;
215 #endif
216 }
217
218 julong os::physical_memory() {
219 return Bsd::physical_memory();
220 }
221
222 julong os::allocatable_physical_memory(julong size) {
223 #ifdef _LP64
224 return size;
225 #else
226 julong result = MIN2(size, (julong)3800*M);
227 if (!is_allocatable(result)) {
228 // See comments under solaris for alignment considerations
229 julong reasonable_size = (julong)2*G - 2 * os::vm_page_size();
230 result = MIN2(size, reasonable_size);
231 }
232 return result;
233 #endif // _LP64
234 }
235
236 ////////////////////////////////////////////////////////////////////////////////
237 // environment support
238
239 bool os::getenv(const char* name, char* buf, int len) {
240 const char* val = ::getenv(name);
241 if (val != NULL && strlen(val) < (size_t)len) {
242 strcpy(buf, val);
243 return true;
244 }
245 if (len > 0) buf[0] = 0; // return a null string
246 return false;
247 }
248
249
250 // Return true if user is running as root.
251
252 bool os::have_special_privileges() {
253 static bool init = false;
254 static bool privileges = false;
255 if (!init) {
256 privileges = (getuid() != geteuid()) || (getgid() != getegid());
257 init = true;
258 }
259 return privileges;
260 }
261
262
263 #ifndef _ALLBSD_SOURCE
264 #ifndef SYS_gettid
265 // i386: 224, ia64: 1105, amd64: 186, sparc 143
266 #ifdef __ia64__
267 #define SYS_gettid 1105
268 #elif __i386__
269 #define SYS_gettid 224
270 #elif __amd64__
271 #define SYS_gettid 186
272 #elif __sparc__
273 #define SYS_gettid 143
274 #else
275 #error define gettid for the arch
276 #endif
277 #endif
278 #endif
279
280 // Cpu architecture string
281 #if defined(ZERO)
282 static char cpu_arch[] = ZERO_LIBARCH;
283 #elif defined(IA64)
284 static char cpu_arch[] = "ia64";
285 #elif defined(IA32)
286 static char cpu_arch[] = "i386";
287 #elif defined(AMD64)
288 static char cpu_arch[] = "amd64";
289 #elif defined(ARM)
290 static char cpu_arch[] = "arm";
291 #elif defined(PPC)
292 static char cpu_arch[] = "ppc";
293 #elif defined(SPARC)
294 # ifdef _LP64
295 static char cpu_arch[] = "sparcv9";
296 # else
297 static char cpu_arch[] = "sparc";
298 # endif
299 #else
300 #error Add appropriate cpu_arch setting
301 #endif
302
303
304 #ifndef _ALLBSD_SOURCE
305 // pid_t gettid()
306 //
307 // Returns the kernel thread id of the currently running thread. Kernel
308 // thread id is used to access /proc.
309 //
310 // (Note that getpid() on BsdThreads returns kernel thread id too; but
311 // on NPTL, it returns the same pid for all threads, as required by POSIX.)
312 //
313 pid_t os::Bsd::gettid() {
314 int rslt = syscall(SYS_gettid);
315 if (rslt == -1) {
316 // old kernel, no NPTL support
317 return getpid();
318 } else {
319 return (pid_t)rslt;
320 }
321 }
322
323 // Most versions of bsd have a bug where the number of processors are
324 // determined by looking at the /proc file system. In a chroot environment,
325 // the system call returns 1. This causes the VM to act as if it is
326 // a single processor and elide locking (see is_MP() call).
327 static bool unsafe_chroot_detected = false;
328 static const char *unstable_chroot_error = "/proc file system not found.\n"
329 "Java may be unstable running multithreaded in a chroot "
330 "environment on Bsd when /proc filesystem is not mounted.";
331 #endif
332
333 #ifdef _ALLBSD_SOURCE
334 void os::Bsd::initialize_system_info() {
335 int mib[2];
336 size_t len;
337 int cpu_val;
338 u_long mem_val;
339
340 /* get processors count via hw.ncpus sysctl */
341 mib[0] = CTL_HW;
342 mib[1] = HW_NCPU;
343 len = sizeof(cpu_val);
344 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
345 set_processor_count(cpu_val);
346 }
347 else {
348 set_processor_count(1); // fallback
349 }
350
351 /* get physical memory via hw.usermem sysctl (hw.usermem is used
352 * instead of hw.physmem because we need size of allocatable memory
353 */
354 mib[0] = CTL_HW;
355 mib[1] = HW_USERMEM;
356 len = sizeof(mem_val);
357 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1)
358 _physical_memory = mem_val;
359 else
360 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
361
362 #ifdef __OpenBSD__
363 {
364 // limit _physical_memory memory view on OpenBSD since
365 // datasize rlimit restricts us anyway.
366 struct rlimit limits;
367 getrlimit(RLIMIT_DATA, &limits);
368 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
369 }
370 #endif
371 }
372 #else
373 void os::Bsd::initialize_system_info() {
374 set_processor_count(sysconf(_SC_NPROCESSORS_CONF));
375 if (processor_count() == 1) {
376 pid_t pid = os::Bsd::gettid();
377 char fname[32];
378 jio_snprintf(fname, sizeof(fname), "/proc/%d", pid);
379 FILE *fp = fopen(fname, "r");
380 if (fp == NULL) {
381 unsafe_chroot_detected = true;
382 } else {
383 fclose(fp);
384 }
385 }
386 _physical_memory = (julong)sysconf(_SC_PHYS_PAGES) * (julong)sysconf(_SC_PAGESIZE);
387 assert(processor_count() > 0, "bsd error");
388 }
389 #endif
390
391 void os::init_system_properties_values() {
392 // char arch[12];
393 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
394
395 // The next steps are taken in the product version:
396 //
397 // Obtain the JAVA_HOME value from the location of libjvm[_g].so.
398 // This library should be located at:
399 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm[_g].so.
400 //
401 // If "/jre/lib/" appears at the right place in the path, then we
402 // assume libjvm[_g].so is installed in a JDK and we use this path.
403 //
404 // Otherwise exit with message: "Could not create the Java virtual machine."
405 //
406 // The following extra steps are taken in the debugging version:
407 //
408 // If "/jre/lib/" does NOT appear at the right place in the path
409 // instead of exit check for $JAVA_HOME environment variable.
410 //
411 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
412 // then we append a fake suffix "hotspot/libjvm[_g].so" to this path so
413 // it looks like libjvm[_g].so is installed there
414 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm[_g].so.
415 //
416 // Otherwise exit.
417 //
418 // Important note: if the location of libjvm.so changes this
419 // code needs to be changed accordingly.
420
421 // The next few definitions allow the code to be verbatim:
422 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n))
423 #define getenv(n) ::getenv(n)
424
425 /*
426 * See ld(1):
427 * The linker uses the following search paths to locate required
428 * shared libraries:
429 * 1: ...
430 * ...
431 * 7: The default directories, normally /lib and /usr/lib.
432 */
433 #ifndef DEFAULT_LIBPATH
434 #define DEFAULT_LIBPATH "/lib:/usr/lib"
435 #endif
436
437 #define EXTENSIONS_DIR "/lib/ext"
438 #define ENDORSED_DIR "/lib/endorsed"
439 #define REG_DIR "/usr/java/packages"
440
441 {
442 /* sysclasspath, java_home, dll_dir */
443 {
444 char *home_path;
445 char *dll_path;
446 char *pslash;
447 char buf[MAXPATHLEN];
448 os::jvm_path(buf, sizeof(buf));
449
450 // Found the full path to libjvm.so.
451 // Now cut the path to <java_home>/jre if we can.
452 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
453 pslash = strrchr(buf, '/');
454 if (pslash != NULL)
455 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
456 dll_path = malloc(strlen(buf) + 1);
457 if (dll_path == NULL)
458 return;
459 strcpy(dll_path, buf);
460 Arguments::set_dll_dir(dll_path);
461
462 if (pslash != NULL) {
463 pslash = strrchr(buf, '/');
464 if (pslash != NULL) {
465 *pslash = '\0'; /* get rid of /<arch> */
466 pslash = strrchr(buf, '/');
467 if (pslash != NULL)
468 *pslash = '\0'; /* get rid of /lib */
469 }
470 }
471
472 home_path = malloc(strlen(buf) + 1);
473 if (home_path == NULL)
474 return;
475 strcpy(home_path, buf);
476 Arguments::set_java_home(home_path);
477
478 if (!set_boot_path('/', ':'))
479 return;
480 }
481
482 /*
483 * Where to look for native libraries
484 *
485 * Note: Due to a legacy implementation, most of the library path
486 * is set in the launcher. This was to accomodate linking restrictions
487 * on legacy Bsd implementations (which are no longer supported).
488 * Eventually, all the library path setting will be done here.
489 *
490 * However, to prevent the proliferation of improperly built native
491 * libraries, the new path component /usr/java/packages is added here.
492 * Eventually, all the library path setting will be done here.
493 */
494 {
495 char *ld_library_path;
496
497 /*
498 * Construct the invariant part of ld_library_path. Note that the
499 * space for the colon and the trailing null are provided by the
500 * nulls included by the sizeof operator (so actually we allocate
501 * a byte more than necessary).
502 */
503 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
504 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
505 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
506
507 /*
508 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
509 * should always exist (until the legacy problem cited above is
510 * addressed).
511 */
512 #ifdef __APPLE__
513 char *v = getenv("DYLD_LIBRARY_PATH");
514 #else
515 char *v = getenv("LD_LIBRARY_PATH");
516 #endif
517 if (v != NULL) {
518 char *t = ld_library_path;
519 /* That's +1 for the colon and +1 for the trailing '\0' */
520 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
521 sprintf(ld_library_path, "%s:%s", v, t);
522 }
523 Arguments::set_library_path(ld_library_path);
524 }
525
526 /*
527 * Extensions directories.
528 *
529 * Note that the space for the colon and the trailing null are provided
530 * by the nulls included by the sizeof operator (so actually one byte more
531 * than necessary is allocated).
532 */
533 {
534 char *buf = malloc(strlen(Arguments::get_java_home()) +
535 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
536 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
537 Arguments::get_java_home());
538 Arguments::set_ext_dirs(buf);
539 }
540
541 /* Endorsed standards default directory. */
542 {
543 char * buf;
544 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
545 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
546 Arguments::set_endorsed_dirs(buf);
547 }
548 }
549
550 #undef malloc
551 #undef getenv
552 #undef EXTENSIONS_DIR
553 #undef ENDORSED_DIR
554
555 // Done
556 return;
557 }
558
559 ////////////////////////////////////////////////////////////////////////////////
560 // breakpoint support
561
562 void os::breakpoint() {
563 BREAKPOINT;
564 }
565
566 extern "C" void breakpoint() {
567 // use debugger to set breakpoint here
568 }
569
570 ////////////////////////////////////////////////////////////////////////////////
571 // signal support
572
573 debug_only(static bool signal_sets_initialized = false);
574 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
575
576 bool os::Bsd::is_sig_ignored(int sig) {
577 struct sigaction oact;
578 sigaction(sig, (struct sigaction*)NULL, &oact);
579 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
580 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
581 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
582 return true;
583 else
584 return false;
585 }
586
587 void os::Bsd::signal_sets_init() {
588 // Should also have an assertion stating we are still single-threaded.
589 assert(!signal_sets_initialized, "Already initialized");
590 // Fill in signals that are necessarily unblocked for all threads in
591 // the VM. Currently, we unblock the following signals:
592 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
593 // by -Xrs (=ReduceSignalUsage));
594 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
595 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
596 // the dispositions or masks wrt these signals.
597 // Programs embedding the VM that want to use the above signals for their
598 // own purposes must, at this time, use the "-Xrs" option to prevent
599 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
600 // (See bug 4345157, and other related bugs).
601 // In reality, though, unblocking these signals is really a nop, since
602 // these signals are not blocked by default.
603 sigemptyset(&unblocked_sigs);
604 sigemptyset(&allowdebug_blocked_sigs);
605 sigaddset(&unblocked_sigs, SIGILL);
606 sigaddset(&unblocked_sigs, SIGSEGV);
607 sigaddset(&unblocked_sigs, SIGBUS);
608 sigaddset(&unblocked_sigs, SIGFPE);
609 sigaddset(&unblocked_sigs, SR_signum);
610
611 if (!ReduceSignalUsage) {
612 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
613 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
614 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
615 }
616 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
617 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
618 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
619 }
620 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
621 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
622 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
623 }
624 }
625 // Fill in signals that are blocked by all but the VM thread.
626 sigemptyset(&vm_sigs);
627 if (!ReduceSignalUsage)
628 sigaddset(&vm_sigs, BREAK_SIGNAL);
629 debug_only(signal_sets_initialized = true);
630
631 }
632
633 // These are signals that are unblocked while a thread is running Java.
634 // (For some reason, they get blocked by default.)
635 sigset_t* os::Bsd::unblocked_signals() {
636 assert(signal_sets_initialized, "Not initialized");
637 return &unblocked_sigs;
638 }
639
640 // These are the signals that are blocked while a (non-VM) thread is
641 // running Java. Only the VM thread handles these signals.
642 sigset_t* os::Bsd::vm_signals() {
643 assert(signal_sets_initialized, "Not initialized");
644 return &vm_sigs;
645 }
646
647 // These are signals that are blocked during cond_wait to allow debugger in
648 sigset_t* os::Bsd::allowdebug_blocked_signals() {
649 assert(signal_sets_initialized, "Not initialized");
650 return &allowdebug_blocked_sigs;
651 }
652
653 void os::Bsd::hotspot_sigmask(Thread* thread) {
654
655 //Save caller's signal mask before setting VM signal mask
656 sigset_t caller_sigmask;
657 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
658
659 OSThread* osthread = thread->osthread();
660 osthread->set_caller_sigmask(caller_sigmask);
661
662 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
663
664 if (!ReduceSignalUsage) {
665 if (thread->is_VM_thread()) {
666 // Only the VM thread handles BREAK_SIGNAL ...
667 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
668 } else {
669 // ... all other threads block BREAK_SIGNAL
670 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
671 }
672 }
673 }
674
675 #ifndef _ALLBSD_SOURCE
676 //////////////////////////////////////////////////////////////////////////////
677 // detecting pthread library
678
679 void os::Bsd::libpthread_init() {
680 // Save glibc and pthread version strings. Note that _CS_GNU_LIBC_VERSION
681 // and _CS_GNU_LIBPTHREAD_VERSION are supported in glibc >= 2.3.2. Use a
682 // generic name for earlier versions.
683 // Define macros here so we can build HotSpot on old systems.
684 # ifndef _CS_GNU_LIBC_VERSION
685 # define _CS_GNU_LIBC_VERSION 2
686 # endif
687 # ifndef _CS_GNU_LIBPTHREAD_VERSION
688 # define _CS_GNU_LIBPTHREAD_VERSION 3
689 # endif
690
691 size_t n = confstr(_CS_GNU_LIBC_VERSION, NULL, 0);
692 if (n > 0) {
693 char *str = (char *)malloc(n);
694 confstr(_CS_GNU_LIBC_VERSION, str, n);
695 os::Bsd::set_glibc_version(str);
696 } else {
697 // _CS_GNU_LIBC_VERSION is not supported, try gnu_get_libc_version()
698 static char _gnu_libc_version[32];
699 jio_snprintf(_gnu_libc_version, sizeof(_gnu_libc_version),
700 "glibc %s %s", gnu_get_libc_version(), gnu_get_libc_release());
701 os::Bsd::set_glibc_version(_gnu_libc_version);
702 }
703
704 n = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, 0);
705 if (n > 0) {
706 char *str = (char *)malloc(n);
707 confstr(_CS_GNU_LIBPTHREAD_VERSION, str, n);
708 // Vanilla RH-9 (glibc 2.3.2) has a bug that confstr() always tells
709 // us "NPTL-0.29" even we are running with BsdThreads. Check if this
710 // is the case. BsdThreads has a hard limit on max number of threads.
711 // So sysconf(_SC_THREAD_THREADS_MAX) will return a positive value.
712 // On the other hand, NPTL does not have such a limit, sysconf()
713 // will return -1 and errno is not changed. Check if it is really NPTL.
714 if (strcmp(os::Bsd::glibc_version(), "glibc 2.3.2") == 0 &&
715 strstr(str, "NPTL") &&
716 sysconf(_SC_THREAD_THREADS_MAX) > 0) {
717 free(str);
718 os::Bsd::set_libpthread_version("bsdthreads");
719 } else {
720 os::Bsd::set_libpthread_version(str);
721 }
722 } else {
723 // glibc before 2.3.2 only has BsdThreads.
724 os::Bsd::set_libpthread_version("bsdthreads");
725 }
726
727 if (strstr(libpthread_version(), "NPTL")) {
728 os::Bsd::set_is_NPTL();
729 } else {
730 os::Bsd::set_is_BsdThreads();
731 }
732
733 // BsdThreads have two flavors: floating-stack mode, which allows variable
734 // stack size; and fixed-stack mode. NPTL is always floating-stack.
735 if (os::Bsd::is_NPTL() || os::Bsd::supports_variable_stack_size()) {
736 os::Bsd::set_is_floating_stack();
737 }
738 }
739
740 /////////////////////////////////////////////////////////////////////////////
741 // thread stack
742
743 // Force Bsd kernel to expand current thread stack. If "bottom" is close
744 // to the stack guard, caller should block all signals.
745 //
746 // MAP_GROWSDOWN:
747 // A special mmap() flag that is used to implement thread stacks. It tells
748 // kernel that the memory region should extend downwards when needed. This
749 // allows early versions of BsdThreads to only mmap the first few pages
750 // when creating a new thread. Bsd kernel will automatically expand thread
751 // stack as needed (on page faults).
752 //
753 // However, because the memory region of a MAP_GROWSDOWN stack can grow on
754 // demand, if a page fault happens outside an already mapped MAP_GROWSDOWN
755 // region, it's hard to tell if the fault is due to a legitimate stack
756 // access or because of reading/writing non-exist memory (e.g. buffer
757 // overrun). As a rule, if the fault happens below current stack pointer,
758 // Bsd kernel does not expand stack, instead a SIGSEGV is sent to the
759 // application (see Bsd kernel fault.c).
760 //
761 // This Bsd feature can cause SIGSEGV when VM bangs thread stack for
762 // stack overflow detection.
763 //
764 // Newer version of BsdThreads (since glibc-2.2, or, RH-7.x) and NPTL do
765 // not use this flag. However, the stack of initial thread is not created
766 // by pthread, it is still MAP_GROWSDOWN. Also it's possible (though
767 // unlikely) that user code can create a thread with MAP_GROWSDOWN stack
768 // and then attach the thread to JVM.
769 //
770 // To get around the problem and allow stack banging on Bsd, we need to
771 // manually expand thread stack after receiving the SIGSEGV.
772 //
773 // There are two ways to expand thread stack to address "bottom", we used
774 // both of them in JVM before 1.5:
775 // 1. adjust stack pointer first so that it is below "bottom", and then
776 // touch "bottom"
777 // 2. mmap() the page in question
778 //
779 // Now alternate signal stack is gone, it's harder to use 2. For instance,
780 // if current sp is already near the lower end of page 101, and we need to
781 // call mmap() to map page 100, it is possible that part of the mmap() frame
782 // will be placed in page 100. When page 100 is mapped, it is zero-filled.
783 // That will destroy the mmap() frame and cause VM to crash.
784 //
785 // The following code works by adjusting sp first, then accessing the "bottom"
786 // page to force a page fault. Bsd kernel will then automatically expand the
787 // stack mapping.
788 //
789 // _expand_stack_to() assumes its frame size is less than page size, which
790 // should always be true if the function is not inlined.
791
792 #if __GNUC__ < 3 // gcc 2.x does not support noinline attribute
793 #define NOINLINE
794 #else
795 #define NOINLINE __attribute__ ((noinline))
796 #endif
797
798 static void _expand_stack_to(address bottom) NOINLINE;
799
800 static void _expand_stack_to(address bottom) {
801 address sp;
802 size_t size;
803 volatile char *p;
804
805 // Adjust bottom to point to the largest address within the same page, it
806 // gives us a one-page buffer if alloca() allocates slightly more memory.
807 bottom = (address)align_size_down((uintptr_t)bottom, os::Bsd::page_size());
808 bottom += os::Bsd::page_size() - 1;
809
810 // sp might be slightly above current stack pointer; if that's the case, we
811 // will alloca() a little more space than necessary, which is OK. Don't use
812 // os::current_stack_pointer(), as its result can be slightly below current
813 // stack pointer, causing us to not alloca enough to reach "bottom".
814 sp = (address)&sp;
815
816 if (sp > bottom) {
817 size = sp - bottom;
818 p = (volatile char *)alloca(size);
819 assert(p != NULL && p <= (volatile char *)bottom, "alloca problem?");
820 p[0] = '\0';
821 }
822 }
823
824 bool os::Bsd::manually_expand_stack(JavaThread * t, address addr) {
825 assert(t!=NULL, "just checking");
826 assert(t->osthread()->expanding_stack(), "expand should be set");
827 assert(t->stack_base() != NULL, "stack_base was not initialized");
828
829 if (addr < t->stack_base() && addr >= t->stack_yellow_zone_base()) {
830 sigset_t mask_all, old_sigset;
831 sigfillset(&mask_all);
832 pthread_sigmask(SIG_SETMASK, &mask_all, &old_sigset);
833 _expand_stack_to(addr);
834 pthread_sigmask(SIG_SETMASK, &old_sigset, NULL);
835 return true;
836 }
837 return false;
838 }
839 #endif
840
841 //////////////////////////////////////////////////////////////////////////////
842 // create new thread
843
844 static address highest_vm_reserved_address();
845
846 // check if it's safe to start a new thread
847 static bool _thread_safety_check(Thread* thread) {
848 #ifdef _ALLBSD_SOURCE
849 return true;
850 #else
851 if (os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack()) {
852 // Fixed stack BsdThreads (SuSE Bsd/x86, and some versions of Redhat)
853 // Heap is mmap'ed at lower end of memory space. Thread stacks are
854 // allocated (MAP_FIXED) from high address space. Every thread stack
855 // occupies a fixed size slot (usually 2Mbytes, but user can change
856 // it to other values if they rebuild BsdThreads).
857 //
858 // Problem with MAP_FIXED is that mmap() can still succeed even part of
859 // the memory region has already been mmap'ed. That means if we have too
860 // many threads and/or very large heap, eventually thread stack will
861 // collide with heap.
862 //
863 // Here we try to prevent heap/stack collision by comparing current
864 // stack bottom with the highest address that has been mmap'ed by JVM
865 // plus a safety margin for memory maps created by native code.
866 //
867 // This feature can be disabled by setting ThreadSafetyMargin to 0
868 //
869 if (ThreadSafetyMargin > 0) {
870 address stack_bottom = os::current_stack_base() - os::current_stack_size();
871
872 // not safe if our stack extends below the safety margin
873 return stack_bottom - ThreadSafetyMargin >= highest_vm_reserved_address();
874 } else {
875 return true;
876 }
877 } else {
878 // Floating stack BsdThreads or NPTL:
879 // Unlike fixed stack BsdThreads, thread stacks are not MAP_FIXED. When
880 // there's not enough space left, pthread_create() will fail. If we come
881 // here, that means enough space has been reserved for stack.
882 return true;
883 }
884 #endif
885 }
886
887 // Thread start routine for all newly created threads
888 static void *java_start(Thread *thread) {
889 // Try to randomize the cache line index of hot stack frames.
890 // This helps when threads of the same stack traces evict each other's
891 // cache lines. The threads can be either from the same JVM instance, or
892 // from different JVM instances. The benefit is especially true for
893 // processors with hyperthreading technology.
894 static int counter = 0;
895 int pid = os::current_process_id();
896 alloca(((pid ^ counter++) & 7) * 128);
897
898 ThreadLocalStorage::set_thread(thread);
899
900 OSThread* osthread = thread->osthread();
901 Monitor* sync = osthread->startThread_lock();
902
903 // non floating stack BsdThreads needs extra check, see above
904 if (!_thread_safety_check(thread)) {
905 // notify parent thread
906 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
907 osthread->set_state(ZOMBIE);
908 sync->notify_all();
909 return NULL;
910 }
911
912 #ifdef _ALLBSD_SOURCE
913 // thread_id is pthread_id on BSD
914 osthread->set_thread_id(::pthread_self());
915 #else
916 // thread_id is kernel thread id (similar to Solaris LWP id)
917 osthread->set_thread_id(os::Bsd::gettid());
918
919 if (UseNUMA) {
920 int lgrp_id = os::numa_get_group_id();
921 if (lgrp_id != -1) {
922 thread->set_lgrp_id(lgrp_id);
923 }
924 }
925 #endif
926 // initialize signal mask for this thread
927 os::Bsd::hotspot_sigmask(thread);
928
929 // initialize floating point control register
930 os::Bsd::init_thread_fpu_state();
931
932 // handshaking with parent thread
933 {
934 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
935
936 // notify parent thread
937 osthread->set_state(INITIALIZED);
938 sync->notify_all();
939
940 // wait until os::start_thread()
941 while (osthread->get_state() == INITIALIZED) {
942 sync->wait(Mutex::_no_safepoint_check_flag);
943 }
944 }
945
946 // call one more level start routine
947 thread->run();
948
949 return 0;
950 }
951
952 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
953 assert(thread->osthread() == NULL, "caller responsible");
954
955 // Allocate the OSThread object
956 OSThread* osthread = new OSThread(NULL, NULL);
957 if (osthread == NULL) {
958 return false;
959 }
960
961 // set the correct thread state
962 osthread->set_thread_type(thr_type);
963
964 // Initial state is ALLOCATED but not INITIALIZED
965 osthread->set_state(ALLOCATED);
966
967 thread->set_osthread(osthread);
968
969 // init thread attributes
970 pthread_attr_t attr;
971 pthread_attr_init(&attr);
972 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
973
974 // stack size
975 if (os::Bsd::supports_variable_stack_size()) {
976 // calculate stack size if it's not specified by caller
977 if (stack_size == 0) {
978 stack_size = os::Bsd::default_stack_size(thr_type);
979
980 switch (thr_type) {
981 case os::java_thread:
982 // Java threads use ThreadStackSize which default value can be
983 // changed with the flag -Xss
984 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
985 stack_size = JavaThread::stack_size_at_create();
986 break;
987 case os::compiler_thread:
988 if (CompilerThreadStackSize > 0) {
989 stack_size = (size_t)(CompilerThreadStackSize * K);
990 break;
991 } // else fall through:
992 // use VMThreadStackSize if CompilerThreadStackSize is not defined
993 case os::vm_thread:
994 case os::pgc_thread:
995 case os::cgc_thread:
996 case os::watcher_thread:
997 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
998 break;
999 }
1000 }
1001
1002 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
1003 pthread_attr_setstacksize(&attr, stack_size);
1004 } else {
1005 // let pthread_create() pick the default value.
1006 }
1007
1008 #ifndef _ALLBSD_SOURCE
1009 // glibc guard page
1010 pthread_attr_setguardsize(&attr, os::Bsd::default_guard_size(thr_type));
1011 #endif
1012
1013 ThreadState state;
1014
1015 {
1016
1017 #ifndef _ALLBSD_SOURCE
1018 // Serialize thread creation if we are running with fixed stack BsdThreads
1019 bool lock = os::Bsd::is_BsdThreads() && !os::Bsd::is_floating_stack();
1020 if (lock) {
1021 os::Bsd::createThread_lock()->lock_without_safepoint_check();
1022 }
1023 #endif
1024
1025 pthread_t tid;
1026 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
1027
1028 pthread_attr_destroy(&attr);
1029
1030 if (ret != 0) {
1031 if (PrintMiscellaneous && (Verbose || WizardMode)) {
1032 perror("pthread_create()");
1033 }
1034 // Need to clean up stuff we've allocated so far
1035 thread->set_osthread(NULL);
1036 delete osthread;
1037 #ifndef _ALLBSD_SOURCE
1038 if (lock) os::Bsd::createThread_lock()->unlock();
1039 #endif
1040 return false;
1041 }
1042
1043 // Store pthread info into the OSThread
1044 osthread->set_pthread_id(tid);
1045
1046 // Wait until child thread is either initialized or aborted
1047 {
1048 Monitor* sync_with_child = osthread->startThread_lock();
1049 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
1050 while ((state = osthread->get_state()) == ALLOCATED) {
1051 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
1052 }
1053 }
1054
1055 #ifndef _ALLBSD_SOURCE
1056 if (lock) {
1057 os::Bsd::createThread_lock()->unlock();
1058 }
1059 #endif
1060 }
1061
1062 // Aborted due to thread limit being reached
1063 if (state == ZOMBIE) {
1064 thread->set_osthread(NULL);
1065 delete osthread;
1066 return false;
1067 }
1068
1069 // The thread is returned suspended (in state INITIALIZED),
1070 // and is started higher up in the call chain
1071 assert(state == INITIALIZED, "race condition");
1072 return true;
1073 }
1074
1075 /////////////////////////////////////////////////////////////////////////////
1076 // attach existing thread
1077
1078 // bootstrap the main thread
1079 bool os::create_main_thread(JavaThread* thread) {
1080 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
1081 return create_attached_thread(thread);
1082 }
1083
1084 bool os::create_attached_thread(JavaThread* thread) {
1085 #ifdef ASSERT
1086 thread->verify_not_published();
1087 #endif
1088
1089 // Allocate the OSThread object
1090 OSThread* osthread = new OSThread(NULL, NULL);
1091
1092 if (osthread == NULL) {
1093 return false;
1094 }
1095
1096 // Store pthread info into the OSThread
1097 #ifdef _ALLBSD_SOURCE
1098 osthread->set_thread_id(::pthread_self());
1099 #else
1100 osthread->set_thread_id(os::Bsd::gettid());
1101 #endif
1102 osthread->set_pthread_id(::pthread_self());
1103
1104 // initialize floating point control register
1105 os::Bsd::init_thread_fpu_state();
1106
1107 // Initial thread state is RUNNABLE
1108 osthread->set_state(RUNNABLE);
1109
1110 thread->set_osthread(osthread);
1111
1112 #ifndef _ALLBSD_SOURCE
1113 if (UseNUMA) {
1114 int lgrp_id = os::numa_get_group_id();
1115 if (lgrp_id != -1) {
1116 thread->set_lgrp_id(lgrp_id);
1117 }
1118 }
1119
1120 if (os::Bsd::is_initial_thread()) {
1121 // If current thread is initial thread, its stack is mapped on demand,
1122 // see notes about MAP_GROWSDOWN. Here we try to force kernel to map
1123 // the entire stack region to avoid SEGV in stack banging.
1124 // It is also useful to get around the heap-stack-gap problem on SuSE
1125 // kernel (see 4821821 for details). We first expand stack to the top
1126 // of yellow zone, then enable stack yellow zone (order is significant,
1127 // enabling yellow zone first will crash JVM on SuSE Bsd), so there
1128 // is no gap between the last two virtual memory regions.
1129
1130 JavaThread *jt = (JavaThread *)thread;
1131 address addr = jt->stack_yellow_zone_base();
1132 assert(addr != NULL, "initialization problem?");
1133 assert(jt->stack_available(addr) > 0, "stack guard should not be enabled");
1134
1135 osthread->set_expanding_stack();
1136 os::Bsd::manually_expand_stack(jt, addr);
1137 osthread->clear_expanding_stack();
1138 }
1139 #endif
1140
1141 // initialize signal mask for this thread
1142 // and save the caller's signal mask
1143 os::Bsd::hotspot_sigmask(thread);
1144
1145 return true;
1146 }
1147
1148 void os::pd_start_thread(Thread* thread) {
1149 OSThread * osthread = thread->osthread();
1150 assert(osthread->get_state() != INITIALIZED, "just checking");
1151 Monitor* sync_with_child = osthread->startThread_lock();
1152 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
1153 sync_with_child->notify();
1154 }
1155
1156 // Free Bsd resources related to the OSThread
1157 void os::free_thread(OSThread* osthread) {
1158 assert(osthread != NULL, "osthread not set");
1159
1160 if (Thread::current()->osthread() == osthread) {
1161 // Restore caller's signal mask
1162 sigset_t sigmask = osthread->caller_sigmask();
1163 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
1164 }
1165
1166 delete osthread;
1167 }
1168
1169 //////////////////////////////////////////////////////////////////////////////
1170 // thread local storage
1171
1172 int os::allocate_thread_local_storage() {
1173 pthread_key_t key;
1174 int rslt = pthread_key_create(&key, NULL);
1175 assert(rslt == 0, "cannot allocate thread local storage");
1176 return (int)key;
1177 }
1178
1179 // Note: This is currently not used by VM, as we don't destroy TLS key
1180 // on VM exit.
1181 void os::free_thread_local_storage(int index) {
1182 int rslt = pthread_key_delete((pthread_key_t)index);
1183 assert(rslt == 0, "invalid index");
1184 }
1185
1186 void os::thread_local_storage_at_put(int index, void* value) {
1187 int rslt = pthread_setspecific((pthread_key_t)index, value);
1188 assert(rslt == 0, "pthread_setspecific failed");
1189 }
1190
1191 extern "C" Thread* get_thread() {
1192 return ThreadLocalStorage::thread();
1193 }
1194
1195 //////////////////////////////////////////////////////////////////////////////
1196 // initial thread
1197
1198 #ifndef _ALLBSD_SOURCE
1199 // Check if current thread is the initial thread, similar to Solaris thr_main.
1200 bool os::Bsd::is_initial_thread(void) {
1201 char dummy;
1202 // If called before init complete, thread stack bottom will be null.
1203 // Can be called if fatal error occurs before initialization.
1204 if (initial_thread_stack_bottom() == NULL) return false;
1205 assert(initial_thread_stack_bottom() != NULL &&
1206 initial_thread_stack_size() != 0,
1207 "os::init did not locate initial thread's stack region");
1208 if ((address)&dummy >= initial_thread_stack_bottom() &&
1209 (address)&dummy < initial_thread_stack_bottom() + initial_thread_stack_size())
1210 return true;
1211 else return false;
1212 }
1213
1214 // Find the virtual memory area that contains addr
1215 static bool find_vma(address addr, address* vma_low, address* vma_high) {
1216 FILE *fp = fopen("/proc/self/maps", "r");
1217 if (fp) {
1218 address low, high;
1219 while (!feof(fp)) {
1220 if (fscanf(fp, "%p-%p", &low, &high) == 2) {
1221 if (low <= addr && addr < high) {
1222 if (vma_low) *vma_low = low;
1223 if (vma_high) *vma_high = high;
1224 fclose (fp);
1225 return true;
1226 }
1227 }
1228 for (;;) {
1229 int ch = fgetc(fp);
1230 if (ch == EOF || ch == (int)'\n') break;
1231 }
1232 }
1233 fclose(fp);
1234 }
1235 return false;
1236 }
1237
1238 // Locate initial thread stack. This special handling of initial thread stack
1239 // is needed because pthread_getattr_np() on most (all?) Bsd distros returns
1240 // bogus value for initial thread.
1241 void os::Bsd::capture_initial_stack(size_t max_size) {
1242 // stack size is the easy part, get it from RLIMIT_STACK
1243 size_t stack_size;
1244 struct rlimit rlim;
1245 getrlimit(RLIMIT_STACK, &rlim);
1246 stack_size = rlim.rlim_cur;
1247
1248 // 6308388: a bug in ld.so will relocate its own .data section to the
1249 // lower end of primordial stack; reduce ulimit -s value a little bit
1250 // so we won't install guard page on ld.so's data section.
1251 stack_size -= 2 * page_size();
1252
1253 // 4441425: avoid crash with "unlimited" stack size on SuSE 7.1 or Redhat
1254 // 7.1, in both cases we will get 2G in return value.
1255 // 4466587: glibc 2.2.x compiled w/o "--enable-kernel=2.4.0" (RH 7.0,
1256 // SuSE 7.2, Debian) can not handle alternate signal stack correctly
1257 // for initial thread if its stack size exceeds 6M. Cap it at 2M,
1258 // in case other parts in glibc still assumes 2M max stack size.
1259 // FIXME: alt signal stack is gone, maybe we can relax this constraint?
1260 #ifndef IA64
1261 if (stack_size > 2 * K * K) stack_size = 2 * K * K;
1262 #else
1263 // Problem still exists RH7.2 (IA64 anyway) but 2MB is a little small
1264 if (stack_size > 4 * K * K) stack_size = 4 * K * K;
1265 #endif
1266
1267 // Try to figure out where the stack base (top) is. This is harder.
1268 //
1269 // When an application is started, glibc saves the initial stack pointer in
1270 // a global variable "__libc_stack_end", which is then used by system
1271 // libraries. __libc_stack_end should be pretty close to stack top. The
1272 // variable is available since the very early days. However, because it is
1273 // a private interface, it could disappear in the future.
1274 //
1275 // Bsd kernel saves start_stack information in /proc/<pid>/stat. Similar
1276 // to __libc_stack_end, it is very close to stack top, but isn't the real
1277 // stack top. Note that /proc may not exist if VM is running as a chroot
1278 // program, so reading /proc/<pid>/stat could fail. Also the contents of
1279 // /proc/<pid>/stat could change in the future (though unlikely).
1280 //
1281 // We try __libc_stack_end first. If that doesn't work, look for
1282 // /proc/<pid>/stat. If neither of them works, we use current stack pointer
1283 // as a hint, which should work well in most cases.
1284
1285 uintptr_t stack_start;
1286
1287 // try __libc_stack_end first
1288 uintptr_t *p = (uintptr_t *)dlsym(RTLD_DEFAULT, "__libc_stack_end");
1289 if (p && *p) {
1290 stack_start = *p;
1291 } else {
1292 // see if we can get the start_stack field from /proc/self/stat
1293 FILE *fp;
1294 int pid;
1295 char state;
1296 int ppid;
1297 int pgrp;
1298 int session;
1299 int nr;
1300 int tpgrp;
1301 unsigned long flags;
1302 unsigned long minflt;
1303 unsigned long cminflt;
1304 unsigned long majflt;
1305 unsigned long cmajflt;
1306 unsigned long utime;
1307 unsigned long stime;
1308 long cutime;
1309 long cstime;
1310 long prio;
1311 long nice;
1312 long junk;
1313 long it_real;
1314 uintptr_t start;
1315 uintptr_t vsize;
1316 intptr_t rss;
1317 uintptr_t rsslim;
1318 uintptr_t scodes;
1319 uintptr_t ecode;
1320 int i;
1321
1322 // Figure what the primordial thread stack base is. Code is inspired
1323 // by email from Hans Boehm. /proc/self/stat begins with current pid,
1324 // followed by command name surrounded by parentheses, state, etc.
1325 char stat[2048];
1326 int statlen;
1327
1328 fp = fopen("/proc/self/stat", "r");
1329 if (fp) {
1330 statlen = fread(stat, 1, 2047, fp);
1331 stat[statlen] = '\0';
1332 fclose(fp);
1333
1334 // Skip pid and the command string. Note that we could be dealing with
1335 // weird command names, e.g. user could decide to rename java launcher
1336 // to "java 1.4.2 :)", then the stat file would look like
1337 // 1234 (java 1.4.2 :)) R ... ...
1338 // We don't really need to know the command string, just find the last
1339 // occurrence of ")" and then start parsing from there. See bug 4726580.
1340 char * s = strrchr(stat, ')');
1341
1342 i = 0;
1343 if (s) {
1344 // Skip blank chars
1345 do s++; while (isspace(*s));
1346
1347 #define _UFM UINTX_FORMAT
1348 #define _DFM INTX_FORMAT
1349
1350 /* 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 */
1351 /* 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 */
1352 i = sscanf(s, "%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld " _UFM _UFM _DFM _UFM _UFM _UFM _UFM,
1353 &state, /* 3 %c */
1354 &ppid, /* 4 %d */
1355 &pgrp, /* 5 %d */
1356 &session, /* 6 %d */
1357 &nr, /* 7 %d */
1358 &tpgrp, /* 8 %d */
1359 &flags, /* 9 %lu */
1360 &minflt, /* 10 %lu */
1361 &cminflt, /* 11 %lu */
1362 &majflt, /* 12 %lu */
1363 &cmajflt, /* 13 %lu */
1364 &utime, /* 14 %lu */
1365 &stime, /* 15 %lu */
1366 &cutime, /* 16 %ld */
1367 &cstime, /* 17 %ld */
1368 &prio, /* 18 %ld */
1369 &nice, /* 19 %ld */
1370 &junk, /* 20 %ld */
1371 &it_real, /* 21 %ld */
1372 &start, /* 22 UINTX_FORMAT */
1373 &vsize, /* 23 UINTX_FORMAT */
1374 &rss, /* 24 INTX_FORMAT */
1375 &rsslim, /* 25 UINTX_FORMAT */
1376 &scodes, /* 26 UINTX_FORMAT */
1377 &ecode, /* 27 UINTX_FORMAT */
1378 &stack_start); /* 28 UINTX_FORMAT */
1379 }
1380
1381 #undef _UFM
1382 #undef _DFM
1383
1384 if (i != 28 - 2) {
1385 assert(false, "Bad conversion from /proc/self/stat");
1386 // product mode - assume we are the initial thread, good luck in the
1387 // embedded case.
1388 warning("Can't detect initial thread stack location - bad conversion");
1389 stack_start = (uintptr_t) &rlim;
1390 }
1391 } else {
1392 // For some reason we can't open /proc/self/stat (for example, running on
1393 // FreeBSD with a Bsd emulator, or inside chroot), this should work for
1394 // most cases, so don't abort:
1395 warning("Can't detect initial thread stack location - no /proc/self/stat");
1396 stack_start = (uintptr_t) &rlim;
1397 }
1398 }
1399
1400 // Now we have a pointer (stack_start) very close to the stack top, the
1401 // next thing to do is to figure out the exact location of stack top. We
1402 // can find out the virtual memory area that contains stack_start by
1403 // reading /proc/self/maps, it should be the last vma in /proc/self/maps,
1404 // and its upper limit is the real stack top. (again, this would fail if
1405 // running inside chroot, because /proc may not exist.)
1406
1407 uintptr_t stack_top;
1408 address low, high;
1409 if (find_vma((address)stack_start, &low, &high)) {
1410 // success, "high" is the true stack top. (ignore "low", because initial
1411 // thread stack grows on demand, its real bottom is high - RLIMIT_STACK.)
1412 stack_top = (uintptr_t)high;
1413 } else {
1414 // failed, likely because /proc/self/maps does not exist
1415 warning("Can't detect initial thread stack location - find_vma failed");
1416 // best effort: stack_start is normally within a few pages below the real
1417 // stack top, use it as stack top, and reduce stack size so we won't put
1418 // guard page outside stack.
1419 stack_top = stack_start;
1420 stack_size -= 16 * page_size();
1421 }
1422
1423 // stack_top could be partially down the page so align it
1424 stack_top = align_size_up(stack_top, page_size());
1425
1426 if (max_size && stack_size > max_size) {
1427 _initial_thread_stack_size = max_size;
1428 } else {
1429 _initial_thread_stack_size = stack_size;
1430 }
1431
1432 _initial_thread_stack_size = align_size_down(_initial_thread_stack_size, page_size());
1433 _initial_thread_stack_bottom = (address)stack_top - _initial_thread_stack_size;
1434 }
1435 #endif
1436
1437 ////////////////////////////////////////////////////////////////////////////////
1438 // time support
1439
1440 // Time since start-up in seconds to a fine granularity.
1441 // Used by VMSelfDestructTimer and the MemProfiler.
1442 double os::elapsedTime() {
1443
1444 return (double)(os::elapsed_counter()) * 0.000001;
1445 }
1446
1447 jlong os::elapsed_counter() {
1448 timeval time;
1449 int status = gettimeofday(&time, NULL);
1450 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
1451 }
1452
1453 jlong os::elapsed_frequency() {
1454 return (1000 * 1000);
1455 }
1456
1457 // XXX: For now, code this as if BSD does not support vtime.
1458 bool os::supports_vtime() { return false; }
1459 bool os::enable_vtime() { return false; }
1460 bool os::vtime_enabled() { return false; }
1461 double os::elapsedVTime() {
1462 // better than nothing, but not much
1463 return elapsedTime();
1464 }
1465
1466 jlong os::javaTimeMillis() {
1467 timeval time;
1468 int status = gettimeofday(&time, NULL);
1469 assert(status != -1, "bsd error");
1470 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
1471 }
1472
1473 #ifndef CLOCK_MONOTONIC
1474 #define CLOCK_MONOTONIC (1)
1475 #endif
1476
1477 #ifdef __APPLE__
1478 void os::Bsd::clock_init() {
1479 // XXXDARWIN: Investigate replacement monotonic clock
1480 }
1481 #elif defined(_ALLBSD_SOURCE)
1482 void os::Bsd::clock_init() {
1483 struct timespec res;
1484 struct timespec tp;
1485 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
1486 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
1487 // yes, monotonic clock is supported
1488 _clock_gettime = ::clock_gettime;
1489 }
1490 }
1491 #else
1492 void os::Bsd::clock_init() {
1493 // we do dlopen's in this particular order due to bug in bsd
1494 // dynamical loader (see 6348968) leading to crash on exit
1495 void* handle = dlopen("librt.so.1", RTLD_LAZY);
1496 if (handle == NULL) {
1497 handle = dlopen("librt.so", RTLD_LAZY);
1498 }
1499
1500 if (handle) {
1501 int (*clock_getres_func)(clockid_t, struct timespec*) =
1502 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_getres");
1503 int (*clock_gettime_func)(clockid_t, struct timespec*) =
1504 (int(*)(clockid_t, struct timespec*))dlsym(handle, "clock_gettime");
1505 if (clock_getres_func && clock_gettime_func) {
1506 // See if monotonic clock is supported by the kernel. Note that some
1507 // early implementations simply return kernel jiffies (updated every
1508 // 1/100 or 1/1000 second). It would be bad to use such a low res clock
1509 // for nano time (though the monotonic property is still nice to have).
1510 // It's fixed in newer kernels, however clock_getres() still returns
1511 // 1/HZ. We check if clock_getres() works, but will ignore its reported
1512 // resolution for now. Hopefully as people move to new kernels, this
1513 // won't be a problem.
1514 struct timespec res;
1515 struct timespec tp;
1516 if (clock_getres_func (CLOCK_MONOTONIC, &res) == 0 &&
1517 clock_gettime_func(CLOCK_MONOTONIC, &tp) == 0) {
1518 // yes, monotonic clock is supported
1519 _clock_gettime = clock_gettime_func;
1520 } else {
1521 // close librt if there is no monotonic clock
1522 dlclose(handle);
1523 }
1524 }
1525 }
1526 }
1527 #endif
1528
1529 #ifndef _ALLBSD_SOURCE
1530 #ifndef SYS_clock_getres
1531
1532 #if defined(IA32) || defined(AMD64)
1533 #define SYS_clock_getres IA32_ONLY(266) AMD64_ONLY(229)
1534 #define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y)
1535 #else
1536 #warning "SYS_clock_getres not defined for this platform, disabling fast_thread_cpu_time"
1537 #define sys_clock_getres(x,y) -1
1538 #endif
1539
1540 #else
1541 #define sys_clock_getres(x,y) ::syscall(SYS_clock_getres, x, y)
1542 #endif
1543
1544 void os::Bsd::fast_thread_clock_init() {
1545 if (!UseBsdPosixThreadCPUClocks) {
1546 return;
1547 }
1548 clockid_t clockid;
1549 struct timespec tp;
1550 int (*pthread_getcpuclockid_func)(pthread_t, clockid_t *) =
1551 (int(*)(pthread_t, clockid_t *)) dlsym(RTLD_DEFAULT, "pthread_getcpuclockid");
1552
1553 // Switch to using fast clocks for thread cpu time if
1554 // the sys_clock_getres() returns 0 error code.
1555 // Note, that some kernels may support the current thread
1556 // clock (CLOCK_THREAD_CPUTIME_ID) but not the clocks
1557 // returned by the pthread_getcpuclockid().
1558 // If the fast Posix clocks are supported then the sys_clock_getres()
1559 // must return at least tp.tv_sec == 0 which means a resolution
1560 // better than 1 sec. This is extra check for reliability.
1561
1562 if(pthread_getcpuclockid_func &&
1563 pthread_getcpuclockid_func(_main_thread, &clockid) == 0 &&
1564 sys_clock_getres(clockid, &tp) == 0 && tp.tv_sec == 0) {
1565
1566 _supports_fast_thread_cpu_time = true;
1567 _pthread_getcpuclockid = pthread_getcpuclockid_func;
1568 }
1569 }
1570 #endif
1571
1572 jlong os::javaTimeNanos() {
1573 if (Bsd::supports_monotonic_clock()) {
1574 struct timespec tp;
1575 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1576 assert(status == 0, "gettime error");
1577 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1578 return result;
1579 } else {
1580 timeval time;
1581 int status = gettimeofday(&time, NULL);
1582 assert(status != -1, "bsd error");
1583 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1584 return 1000 * usecs;
1585 }
1586 }
1587
1588 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1589 if (Bsd::supports_monotonic_clock()) {
1590 info_ptr->max_value = ALL_64_BITS;
1591
1592 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1593 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1594 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1595 } else {
1596 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1597 info_ptr->max_value = ALL_64_BITS;
1598
1599 // gettimeofday is a real time clock so it skips
1600 info_ptr->may_skip_backward = true;
1601 info_ptr->may_skip_forward = true;
1602 }
1603
1604 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1605 }
1606
1607 // Return the real, user, and system times in seconds from an
1608 // arbitrary fixed point in the past.
1609 bool os::getTimesSecs(double* process_real_time,
1610 double* process_user_time,
1611 double* process_system_time) {
1612 struct tms ticks;
1613 clock_t real_ticks = times(&ticks);
1614
1615 if (real_ticks == (clock_t) (-1)) {
1616 return false;
1617 } else {
1618 double ticks_per_second = (double) clock_tics_per_sec;
1619 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1620 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1621 *process_real_time = ((double) real_ticks) / ticks_per_second;
1622
1623 return true;
1624 }
1625 }
1626
1627
1628 char * os::local_time_string(char *buf, size_t buflen) {
1629 struct tm t;
1630 time_t long_time;
1631 time(&long_time);
1632 localtime_r(&long_time, &t);
1633 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1634 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1635 t.tm_hour, t.tm_min, t.tm_sec);
1636 return buf;
1637 }
1638
1639 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1640 return localtime_r(clock, res);
1641 }
1642
1643 ////////////////////////////////////////////////////////////////////////////////
1644 // runtime exit support
1645
1646 // Note: os::shutdown() might be called very early during initialization, or
1647 // called from signal handler. Before adding something to os::shutdown(), make
1648 // sure it is async-safe and can handle partially initialized VM.
1649 void os::shutdown() {
1650
1651 // allow PerfMemory to attempt cleanup of any persistent resources
1652 perfMemory_exit();
1653
1654 // needs to remove object in file system
1655 AttachListener::abort();
1656
1657 // flush buffered output, finish log files
1658 ostream_abort();
1659
1660 // Check for abort hook
1661 abort_hook_t abort_hook = Arguments::abort_hook();
1662 if (abort_hook != NULL) {
1663 abort_hook();
1664 }
1665
1666 }
1667
1668 // Note: os::abort() might be called very early during initialization, or
1669 // called from signal handler. Before adding something to os::abort(), make
1670 // sure it is async-safe and can handle partially initialized VM.
1671 void os::abort(bool dump_core) {
1672 os::shutdown();
1673 if (dump_core) {
1674 #ifndef PRODUCT
1675 fdStream out(defaultStream::output_fd());
1676 out.print_raw("Current thread is ");
1677 char buf[16];
1678 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1679 out.print_raw_cr(buf);
1680 out.print_raw_cr("Dumping core ...");
1681 #endif
1682 ::abort(); // dump core
1683 }
1684
1685 ::exit(1);
1686 }
1687
1688 // Die immediately, no exit hook, no abort hook, no cleanup.
1689 void os::die() {
1690 // _exit() on BsdThreads only kills current thread
1691 ::abort();
1692 }
1693
1694 // unused on bsd for now.
1695 void os::set_error_file(const char *logfile) {}
1696
1697
1698 // This method is a copy of JDK's sysGetLastErrorString
1699 // from src/solaris/hpi/src/system_md.c
1700
1701 size_t os::lasterror(char *buf, size_t len) {
1702
1703 if (errno == 0) return 0;
1704
1705 const char *s = ::strerror(errno);
1706 size_t n = ::strlen(s);
1707 if (n >= len) {
1708 n = len - 1;
1709 }
1710 ::strncpy(buf, s, n);
1711 buf[n] = '\0';
1712 return n;
1713 }
1714
1715 intx os::current_thread_id() { return (intx)pthread_self(); }
1716 int os::current_process_id() {
1717
1718 // Under the old bsd thread library, bsd gives each thread
1719 // its own process id. Because of this each thread will return
1720 // a different pid if this method were to return the result
1721 // of getpid(2). Bsd provides no api that returns the pid
1722 // of the launcher thread for the vm. This implementation
1723 // returns a unique pid, the pid of the launcher thread
1724 // that starts the vm 'process'.
1725
1726 // Under the NPTL, getpid() returns the same pid as the
1727 // launcher thread rather than a unique pid per thread.
1728 // Use gettid() if you want the old pre NPTL behaviour.
1729
1730 // if you are looking for the result of a call to getpid() that
1731 // returns a unique pid for the calling thread, then look at the
1732 // OSThread::thread_id() method in osThread_bsd.hpp file
1733
1734 return (int)(_initial_pid ? _initial_pid : getpid());
1735 }
1736
1737 // DLL functions
1738
1739 #define JNI_LIB_PREFIX "lib"
1740 #ifdef __APPLE__
1741 #define JNI_LIB_SUFFIX ".dylib"
1742 #else
1743 #define JNI_LIB_SUFFIX ".so"
1744 #endif
1745
1746 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1747
1748 // This must be hard coded because it's the system's temporary
1749 // directory not the java application's temp directory, ala java.io.tmpdir.
1750 const char* os::get_temp_directory() { return "/tmp"; }
1751
1752 static bool file_exists(const char* filename) {
1753 struct stat statbuf;
1754 if (filename == NULL || strlen(filename) == 0) {
1755 return false;
1756 }
1757 return os::stat(filename, &statbuf) == 0;
1758 }
1759
1760 void os::dll_build_name(char* buffer, size_t buflen,
1761 const char* pname, const char* fname) {
1762 // Copied from libhpi
1763 const size_t pnamelen = pname ? strlen(pname) : 0;
1764
1765 // Quietly truncate on buffer overflow. Should be an error.
1766 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1767 *buffer = '\0';
1768 return;
1769 }
1770
1771 if (pnamelen == 0) {
1772 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1773 } else if (strchr(pname, *os::path_separator()) != NULL) {
1774 int n;
1775 char** pelements = split_path(pname, &n);
1776 for (int i = 0 ; i < n ; i++) {
1777 // Really shouldn't be NULL, but check can't hurt
1778 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1779 continue; // skip the empty path values
1780 }
1781 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1782 pelements[i], fname);
1783 if (file_exists(buffer)) {
1784 break;
1785 }
1786 }
1787 // release the storage
1788 for (int i = 0 ; i < n ; i++) {
1789 if (pelements[i] != NULL) {
1790 FREE_C_HEAP_ARRAY(char, pelements[i]);
1791 }
1792 }
1793 if (pelements != NULL) {
1794 FREE_C_HEAP_ARRAY(char*, pelements);
1795 }
1796 } else {
1797 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1798 }
1799 }
1800
1801 const char* os::get_current_directory(char *buf, int buflen) {
1802 return getcwd(buf, buflen);
1803 }
1804
1805 // check if addr is inside libjvm[_g].so
1806 bool os::address_is_in_vm(address addr) {
1807 static address libjvm_base_addr;
1808 Dl_info dlinfo;
1809
1810 if (libjvm_base_addr == NULL) {
1811 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1812 libjvm_base_addr = (address)dlinfo.dli_fbase;
1813 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1814 }
1815
1816 if (dladdr((void *)addr, &dlinfo)) {
1817 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1818 }
1819
1820 return false;
1821 }
1822
1823 bool os::dll_address_to_function_name(address addr, char *buf,
1824 int buflen, int *offset) {
1825 Dl_info dlinfo;
1826
1827 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1828 if (buf != NULL) {
1829 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1830 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1831 }
1832 }
1833 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1834 return true;
1835 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1836 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1837 dlinfo.dli_fname, buf, buflen, offset) == Decoder::no_error) {
1838 return true;
1839 }
1840 }
1841
1842 if (buf != NULL) buf[0] = '\0';
1843 if (offset != NULL) *offset = -1;
1844 return false;
1845 }
1846
1847 #ifdef _ALLBSD_SOURCE
1848 // ported from solaris version
1849 bool os::dll_address_to_library_name(address addr, char* buf,
1850 int buflen, int* offset) {
1851 Dl_info dlinfo;
1852
1853 if (dladdr((void*)addr, &dlinfo)){
1854 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1855 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1856 return true;
1857 } else {
1858 if (buf) buf[0] = '\0';
1859 if (offset) *offset = -1;
1860 return false;
1861 }
1862 }
1863 #else
1864 struct _address_to_library_name {
1865 address addr; // input : memory address
1866 size_t buflen; // size of fname
1867 char* fname; // output: library name
1868 address base; // library base addr
1869 };
1870
1871 static int address_to_library_name_callback(struct dl_phdr_info *info,
1872 size_t size, void *data) {
1873 int i;
1874 bool found = false;
1875 address libbase = NULL;
1876 struct _address_to_library_name * d = (struct _address_to_library_name *)data;
1877
1878 // iterate through all loadable segments
1879 for (i = 0; i < info->dlpi_phnum; i++) {
1880 address segbase = (address)(info->dlpi_addr + info->dlpi_phdr[i].p_vaddr);
1881 if (info->dlpi_phdr[i].p_type == PT_LOAD) {
1882 // base address of a library is the lowest address of its loaded
1883 // segments.
1884 if (libbase == NULL || libbase > segbase) {
1885 libbase = segbase;
1886 }
1887 // see if 'addr' is within current segment
1888 if (segbase <= d->addr &&
1889 d->addr < segbase + info->dlpi_phdr[i].p_memsz) {
1890 found = true;
1891 }
1892 }
1893 }
1894
1895 // dlpi_name is NULL or empty if the ELF file is executable, return 0
1896 // so dll_address_to_library_name() can fall through to use dladdr() which
1897 // can figure out executable name from argv[0].
1898 if (found && info->dlpi_name && info->dlpi_name[0]) {
1899 d->base = libbase;
1900 if (d->fname) {
1901 jio_snprintf(d->fname, d->buflen, "%s", info->dlpi_name);
1902 }
1903 return 1;
1904 }
1905 return 0;
1906 }
1907
1908 bool os::dll_address_to_library_name(address addr, char* buf,
1909 int buflen, int* offset) {
1910 Dl_info dlinfo;
1911 struct _address_to_library_name data;
1912
1913 // There is a bug in old glibc dladdr() implementation that it could resolve
1914 // to wrong library name if the .so file has a base address != NULL. Here
1915 // we iterate through the program headers of all loaded libraries to find
1916 // out which library 'addr' really belongs to. This workaround can be
1917 // removed once the minimum requirement for glibc is moved to 2.3.x.
1918 data.addr = addr;
1919 data.fname = buf;
1920 data.buflen = buflen;
1921 data.base = NULL;
1922 int rslt = dl_iterate_phdr(address_to_library_name_callback, (void *)&data);
1923
1924 if (rslt) {
1925 // buf already contains library name
1926 if (offset) *offset = addr - data.base;
1927 return true;
1928 } else if (dladdr((void*)addr, &dlinfo)){
1929 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1930 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1931 return true;
1932 } else {
1933 if (buf) buf[0] = '\0';
1934 if (offset) *offset = -1;
1935 return false;
1936 }
1937 }
1938 #endif
1939
1940 // Loads .dll/.so and
1941 // in case of error it checks if .dll/.so was built for the
1942 // same architecture as Hotspot is running on
1943
1944 #ifdef __APPLE__
1945 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1946 void * result= ::dlopen(filename, RTLD_LAZY);
1947 if (result != NULL) {
1948 // Successful loading
1949 return result;
1950 }
1951
1952 // Read system error message into ebuf
1953 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1954 ebuf[ebuflen-1]='\0';
1955
1956 return NULL;
1957 }
1958 #else
1959 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1960 {
1961 void * result= ::dlopen(filename, RTLD_LAZY);
1962 if (result != NULL) {
1963 // Successful loading
1964 return result;
1965 }
1966
1967 Elf32_Ehdr elf_head;
1968
1969 // Read system error message into ebuf
1970 // It may or may not be overwritten below
1971 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1972 ebuf[ebuflen-1]='\0';
1973 int diag_msg_max_length=ebuflen-strlen(ebuf);
1974 char* diag_msg_buf=ebuf+strlen(ebuf);
1975
1976 if (diag_msg_max_length==0) {
1977 // No more space in ebuf for additional diagnostics message
1978 return NULL;
1979 }
1980
1981
1982 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1983
1984 if (file_descriptor < 0) {
1985 // Can't open library, report dlerror() message
1986 return NULL;
1987 }
1988
1989 bool failed_to_read_elf_head=
1990 (sizeof(elf_head)!=
1991 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1992
1993 ::close(file_descriptor);
1994 if (failed_to_read_elf_head) {
1995 // file i/o error - report dlerror() msg
1996 return NULL;
1997 }
1998
1999 typedef struct {
2000 Elf32_Half code; // Actual value as defined in elf.h
2001 Elf32_Half compat_class; // Compatibility of archs at VM's sense
2002 char elf_class; // 32 or 64 bit
2003 char endianess; // MSB or LSB
2004 char* name; // String representation
2005 } arch_t;
2006
2007 #ifndef EM_486
2008 #define EM_486 6 /* Intel 80486 */
2009 #endif
2010
2011 #ifndef EM_MIPS_RS3_LE
2012 #define EM_MIPS_RS3_LE 10 /* MIPS */
2013 #endif
2014
2015 #ifndef EM_PPC64
2016 #define EM_PPC64 21 /* PowerPC64 */
2017 #endif
2018
2019 #ifndef EM_S390
2020 #define EM_S390 22 /* IBM System/390 */
2021 #endif
2022
2023 #ifndef EM_IA_64
2024 #define EM_IA_64 50 /* HP/Intel IA-64 */
2025 #endif
2026
2027 #ifndef EM_X86_64
2028 #define EM_X86_64 62 /* AMD x86-64 */
2029 #endif
2030
2031 static const arch_t arch_array[]={
2032 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
2033 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
2034 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
2035 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
2036 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
2037 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
2038 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
2039 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
2040 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
2041 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
2042 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
2043 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
2044 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
2045 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
2046 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
2047 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
2048 };
2049
2050 #if (defined IA32)
2051 static Elf32_Half running_arch_code=EM_386;
2052 #elif (defined AMD64)
2053 static Elf32_Half running_arch_code=EM_X86_64;
2054 #elif (defined IA64)
2055 static Elf32_Half running_arch_code=EM_IA_64;
2056 #elif (defined __sparc) && (defined _LP64)
2057 static Elf32_Half running_arch_code=EM_SPARCV9;
2058 #elif (defined __sparc) && (!defined _LP64)
2059 static Elf32_Half running_arch_code=EM_SPARC;
2060 #elif (defined __powerpc64__)
2061 static Elf32_Half running_arch_code=EM_PPC64;
2062 #elif (defined __powerpc__)
2063 static Elf32_Half running_arch_code=EM_PPC;
2064 #elif (defined ARM)
2065 static Elf32_Half running_arch_code=EM_ARM;
2066 #elif (defined S390)
2067 static Elf32_Half running_arch_code=EM_S390;
2068 #elif (defined ALPHA)
2069 static Elf32_Half running_arch_code=EM_ALPHA;
2070 #elif (defined MIPSEL)
2071 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
2072 #elif (defined PARISC)
2073 static Elf32_Half running_arch_code=EM_PARISC;
2074 #elif (defined MIPS)
2075 static Elf32_Half running_arch_code=EM_MIPS;
2076 #elif (defined M68K)
2077 static Elf32_Half running_arch_code=EM_68K;
2078 #else
2079 #error Method os::dll_load requires that one of following is defined:\
2080 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
2081 #endif
2082
2083 // Identify compatability class for VM's architecture and library's architecture
2084 // Obtain string descriptions for architectures
2085
2086 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
2087 int running_arch_index=-1;
2088
2089 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
2090 if (running_arch_code == arch_array[i].code) {
2091 running_arch_index = i;
2092 }
2093 if (lib_arch.code == arch_array[i].code) {
2094 lib_arch.compat_class = arch_array[i].compat_class;
2095 lib_arch.name = arch_array[i].name;
2096 }
2097 }
2098
2099 assert(running_arch_index != -1,
2100 "Didn't find running architecture code (running_arch_code) in arch_array");
2101 if (running_arch_index == -1) {
2102 // Even though running architecture detection failed
2103 // we may still continue with reporting dlerror() message
2104 return NULL;
2105 }
2106
2107 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
2108 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
2109 return NULL;
2110 }
2111
2112 #ifndef S390
2113 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
2114 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
2115 return NULL;
2116 }
2117 #endif // !S390
2118
2119 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
2120 if ( lib_arch.name!=NULL ) {
2121 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
2122 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
2123 lib_arch.name, arch_array[running_arch_index].name);
2124 } else {
2125 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
2126 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
2127 lib_arch.code,
2128 arch_array[running_arch_index].name);
2129 }
2130 }
2131
2132 return NULL;
2133 }
2134 #endif /* !__APPLE__ */
2135
2136 // XXX: Do we need a lock around this as per Linux?
2137 void* os::dll_lookup(void* handle, const char* name) {
2138 return dlsym(handle, name);
2139 }
2140
2141
2142 static bool _print_ascii_file(const char* filename, outputStream* st) {
2143 int fd = ::open(filename, O_RDONLY);
2144 if (fd == -1) {
2145 return false;
2146 }
2147
2148 char buf[32];
2149 int bytes;
2150 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
2151 st->print_raw(buf, bytes);
2152 }
2153
2154 ::close(fd);
2155
2156 return true;
2157 }
2158
2159 void os::print_dll_info(outputStream *st) {
2160 st->print_cr("Dynamic libraries:");
2161 #ifdef _ALLBSD_SOURCE
2162 #ifdef RTLD_DI_LINKMAP
2163 Dl_info dli;
2164 void *handle;
2165 Link_map *map;
2166 Link_map *p;
2167
2168 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
2169 st->print_cr("Error: Cannot print dynamic libraries.");
2170 return;
2171 }
2172 handle = dlopen(dli.dli_fname, RTLD_LAZY);
2173 if (handle == NULL) {
2174 st->print_cr("Error: Cannot print dynamic libraries.");
2175 return;
2176 }
2177 dlinfo(handle, RTLD_DI_LINKMAP, &map);
2178 if (map == NULL) {
2179 st->print_cr("Error: Cannot print dynamic libraries.");
2180 return;
2181 }
2182
2183 while (map->l_prev != NULL)
2184 map = map->l_prev;
2185
2186 while (map != NULL) {
2187 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
2188 map = map->l_next;
2189 }
2190
2191 dlclose(handle);
2192 #elif defined(__APPLE__)
2193 uint32_t count;
2194 uint32_t i;
2195
2196 count = _dyld_image_count();
2197 for (i = 1; i < count; i++) {
2198 const char *name = _dyld_get_image_name(i);
2199 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
2200 st->print_cr(PTR_FORMAT " \t%s", slide, name);
2201 }
2202 #else
2203 st->print_cr("Error: Cannot print dynamic libraries.");
2204 #endif
2205 #else
2206 char fname[32];
2207 pid_t pid = os::Bsd::gettid();
2208
2209 jio_snprintf(fname, sizeof(fname), "/proc/%d/maps", pid);
2210
2211 if (!_print_ascii_file(fname, st)) {
2212 st->print("Can not get library information for pid = %d\n", pid);
2213 }
2214 #endif
2215 }
2216
2217
2218 void os::print_os_info(outputStream* st) {
2219 st->print("OS:");
2220
2221 // Try to identify popular distros.
2222 // Most Bsd distributions have /etc/XXX-release file, which contains
2223 // the OS version string. Some have more than one /etc/XXX-release file
2224 // (e.g. Mandrake has both /etc/mandrake-release and /etc/redhat-release.),
2225 // so the order is important.
2226 if (!_print_ascii_file("/etc/mandrake-release", st) &&
2227 !_print_ascii_file("/etc/sun-release", st) &&
2228 !_print_ascii_file("/etc/redhat-release", st) &&
2229 !_print_ascii_file("/etc/SuSE-release", st) &&
2230 !_print_ascii_file("/etc/turbobsd-release", st) &&
2231 !_print_ascii_file("/etc/gentoo-release", st) &&
2232 !_print_ascii_file("/etc/debian_version", st) &&
2233 !_print_ascii_file("/etc/ltib-release", st) &&
2234 !_print_ascii_file("/etc/angstrom-version", st)) {
2235 st->print("Bsd");
2236 }
2237 st->cr();
2238
2239 // kernel
2240 st->print("uname:");
2241 struct utsname name;
2242 uname(&name);
2243 st->print(name.sysname); st->print(" ");
2244 st->print(name.release); st->print(" ");
2245 st->print(name.version); st->print(" ");
2246 st->print(name.machine);
2247 st->cr();
2248
2249 #ifndef _ALLBSD_SOURCE
2250 // Print warning if unsafe chroot environment detected
2251 if (unsafe_chroot_detected) {
2252 st->print("WARNING!! ");
2253 st->print_cr(unstable_chroot_error);
2254 }
2255
2256 // libc, pthread
2257 st->print("libc:");
2258 st->print(os::Bsd::glibc_version()); st->print(" ");
2259 st->print(os::Bsd::libpthread_version()); st->print(" ");
2260 if (os::Bsd::is_BsdThreads()) {
2261 st->print("(%s stack)", os::Bsd::is_floating_stack() ? "floating" : "fixed");
2262 }
2263 st->cr();
2264 #endif
2265
2266 // rlimit
2267 st->print("rlimit:");
2268 struct rlimit rlim;
2269
2270 st->print(" STACK ");
2271 getrlimit(RLIMIT_STACK, &rlim);
2272 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
2273 else st->print("%uk", rlim.rlim_cur >> 10);
2274
2275 st->print(", CORE ");
2276 getrlimit(RLIMIT_CORE, &rlim);
2277 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
2278 else st->print("%uk", rlim.rlim_cur >> 10);
2279
2280 st->print(", NPROC ");
2281 getrlimit(RLIMIT_NPROC, &rlim);
2282 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
2283 else st->print("%d", rlim.rlim_cur);
2284
2285 st->print(", NOFILE ");
2286 getrlimit(RLIMIT_NOFILE, &rlim);
2287 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
2288 else st->print("%d", rlim.rlim_cur);
2289
2290 #ifndef _ALLBSD_SOURCE
2291 st->print(", AS ");
2292 getrlimit(RLIMIT_AS, &rlim);
2293 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
2294 else st->print("%uk", rlim.rlim_cur >> 10);
2295 st->cr();
2296
2297 // load average
2298 st->print("load average:");
2299 double loadavg[3];
2300 os::loadavg(loadavg, 3);
2301 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
2302 st->cr();
2303 #endif
2304 }
2305
2306 void os::pd_print_cpu_info(outputStream* st) {
2307 // Nothing to do for now.
2308 }
2309
2310 void os::print_memory_info(outputStream* st) {
2311
2312 st->print("Memory:");
2313 st->print(" %dk page", os::vm_page_size()>>10);
2314
2315 #ifndef _ALLBSD_SOURCE
2316 // values in struct sysinfo are "unsigned long"
2317 struct sysinfo si;
2318 sysinfo(&si);
2319 #endif
2320
2321 st->print(", physical " UINT64_FORMAT "k",
2322 os::physical_memory() >> 10);
2323 st->print("(" UINT64_FORMAT "k free)",
2324 os::available_memory() >> 10);
2325 #ifndef _ALLBSD_SOURCE
2326 st->print(", swap " UINT64_FORMAT "k",
2327 ((jlong)si.totalswap * si.mem_unit) >> 10);
2328 st->print("(" UINT64_FORMAT "k free)",
2329 ((jlong)si.freeswap * si.mem_unit) >> 10);
2330 #endif
2331 st->cr();
2332
2333 // meminfo
2334 st->print("\n/proc/meminfo:\n");
2335 _print_ascii_file("/proc/meminfo", st);
2336 st->cr();
2337 }
2338
2339 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
2340 // but they're the same for all the bsd arch that we support
2341 // and they're the same for solaris but there's no common place to put this.
2342 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
2343 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
2344 "ILL_COPROC", "ILL_BADSTK" };
2345
2346 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
2347 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
2348 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
2349
2350 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
2351
2352 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
2353
2354 void os::print_siginfo(outputStream* st, void* siginfo) {
2355 st->print("siginfo:");
2356
2357 const int buflen = 100;
2358 char buf[buflen];
2359 siginfo_t *si = (siginfo_t*)siginfo;
2360 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
2361 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
2362 st->print("si_errno=%s", buf);
2363 } else {
2364 st->print("si_errno=%d", si->si_errno);
2365 }
2366 const int c = si->si_code;
2367 assert(c > 0, "unexpected si_code");
2368 switch (si->si_signo) {
2369 case SIGILL:
2370 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
2371 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
2372 break;
2373 case SIGFPE:
2374 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
2375 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
2376 break;
2377 case SIGSEGV:
2378 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
2379 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
2380 break;
2381 case SIGBUS:
2382 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
2383 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
2384 break;
2385 default:
2386 st->print(", si_code=%d", si->si_code);
2387 // no si_addr
2388 }
2389
2390 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
2391 UseSharedSpaces) {
2392 FileMapInfo* mapinfo = FileMapInfo::current_info();
2393 if (mapinfo->is_in_shared_space(si->si_addr)) {
2394 st->print("\n\nError accessing class data sharing archive." \
2395 " Mapped file inaccessible during execution, " \
2396 " possible disk/network problem.");
2397 }
2398 }
2399 st->cr();
2400 }
2401
2402
2403 static void print_signal_handler(outputStream* st, int sig,
2404 char* buf, size_t buflen);
2405
2406 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
2407 st->print_cr("Signal Handlers:");
2408 print_signal_handler(st, SIGSEGV, buf, buflen);
2409 print_signal_handler(st, SIGBUS , buf, buflen);
2410 print_signal_handler(st, SIGFPE , buf, buflen);
2411 print_signal_handler(st, SIGPIPE, buf, buflen);
2412 print_signal_handler(st, SIGXFSZ, buf, buflen);
2413 print_signal_handler(st, SIGILL , buf, buflen);
2414 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
2415 print_signal_handler(st, SR_signum, buf, buflen);
2416 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
2417 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
2418 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
2419 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
2420 }
2421
2422 static char saved_jvm_path[MAXPATHLEN] = {0};
2423
2424 // Find the full path to the current module, libjvm.so or libjvm_g.so
2425 void os::jvm_path(char *buf, jint buflen) {
2426 // Error checking.
2427 if (buflen < MAXPATHLEN) {
2428 assert(false, "must use a large-enough buffer");
2429 buf[0] = '\0';
2430 return;
2431 }
2432 // Lazy resolve the path to current module.
2433 if (saved_jvm_path[0] != 0) {
2434 strcpy(buf, saved_jvm_path);
2435 return;
2436 }
2437
2438 char dli_fname[MAXPATHLEN];
2439 bool ret = dll_address_to_library_name(
2440 CAST_FROM_FN_PTR(address, os::jvm_path),
2441 dli_fname, sizeof(dli_fname), NULL);
2442 assert(ret != 0, "cannot locate libjvm");
2443 char *rp = realpath(dli_fname, buf);
2444 if (rp == NULL)
2445 return;
2446
2447 if (Arguments::created_by_gamma_launcher()) {
2448 // Support for the gamma launcher. Typical value for buf is
2449 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so". If "/jre/lib/" appears at
2450 // the right place in the string, then assume we are installed in a JDK and
2451 // we're done. Otherwise, check for a JAVA_HOME environment variable and fix
2452 // up the path so it looks like libjvm.so is installed there (append a
2453 // fake suffix hotspot/libjvm.so).
2454 const char *p = buf + strlen(buf) - 1;
2455 for (int count = 0; p > buf && count < 5; ++count) {
2456 for (--p; p > buf && *p != '/'; --p)
2457 /* empty */ ;
2458 }
2459
2460 if (strncmp(p, "/jre/lib/", 9) != 0) {
2461 // Look for JAVA_HOME in the environment.
2462 char* java_home_var = ::getenv("JAVA_HOME");
2463 if (java_home_var != NULL && java_home_var[0] != 0) {
2464 char* jrelib_p;
2465 int len;
2466
2467 // Check the current module name "libjvm.so" or "libjvm_g.so".
2468 p = strrchr(buf, '/');
2469 assert(strstr(p, "/libjvm") == p, "invalid library name");
2470 p = strstr(p, "_g") ? "_g" : "";
2471
2472 rp = realpath(java_home_var, buf);
2473 if (rp == NULL)
2474 return;
2475
2476 // determine if this is a legacy image or modules image
2477 // modules image doesn't have "jre" subdirectory
2478 len = strlen(buf);
2479 jrelib_p = buf + len;
2480 snprintf(jrelib_p, buflen-len, "/jre/lib/%s", cpu_arch);
2481 if (0 != access(buf, F_OK)) {
2482 snprintf(jrelib_p, buflen-len, "/lib/%s", cpu_arch);
2483 }
2484
2485 if (0 == access(buf, F_OK)) {
2486 // Use current module name "libjvm[_g].so" instead of
2487 // "libjvm"debug_only("_g")".so" since for fastdebug version
2488 // we should have "libjvm.so" but debug_only("_g") adds "_g"!
2489 len = strlen(buf);
2490 snprintf(buf + len, buflen-len, "/hotspot/libjvm%s.so", p);
2491 } else {
2492 // Go back to path of .so
2493 rp = realpath(dli_fname, buf);
2494 if (rp == NULL)
2495 return;
2496 }
2497 }
2498 }
2499 }
2500
2501 strcpy(saved_jvm_path, buf);
2502 }
2503
2504 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
2505 // no prefix required, not even "_"
2506 }
2507
2508 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
2509 // no suffix required
2510 }
2511
2512 ////////////////////////////////////////////////////////////////////////////////
2513 // sun.misc.Signal support
2514
2515 static volatile jint sigint_count = 0;
2516
2517 static void
2518 UserHandler(int sig, void *siginfo, void *context) {
2519 // 4511530 - sem_post is serialized and handled by the manager thread. When
2520 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
2521 // don't want to flood the manager thread with sem_post requests.
2522 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
2523 return;
2524
2525 // Ctrl-C is pressed during error reporting, likely because the error
2526 // handler fails to abort. Let VM die immediately.
2527 if (sig == SIGINT && is_error_reported()) {
2528 os::die();
2529 }
2530
2531 os::signal_notify(sig);
2532 }
2533
2534 void* os::user_handler() {
2535 return CAST_FROM_FN_PTR(void*, UserHandler);
2536 }
2537
2538 extern "C" {
2539 typedef void (*sa_handler_t)(int);
2540 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
2541 }
2542
2543 void* os::signal(int signal_number, void* handler) {
2544 struct sigaction sigAct, oldSigAct;
2545
2546 sigfillset(&(sigAct.sa_mask));
2547 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
2548 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
2549
2550 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
2551 // -1 means registration failed
2552 return (void *)-1;
2553 }
2554
2555 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
2556 }
2557
2558 void os::signal_raise(int signal_number) {
2559 ::raise(signal_number);
2560 }
2561
2562 /*
2563 * The following code is moved from os.cpp for making this
2564 * code platform specific, which it is by its very nature.
2565 */
2566
2567 // Will be modified when max signal is changed to be dynamic
2568 int os::sigexitnum_pd() {
2569 return NSIG;
2570 }
2571
2572 // a counter for each possible signal value
2573 static volatile jint pending_signals[NSIG+1] = { 0 };
2574
2575 // Bsd(POSIX) specific hand shaking semaphore.
2576 #ifdef __APPLE__
2577 static semaphore_t sig_sem;
2578 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
2579 #define SEM_WAIT(sem) semaphore_wait(sem);
2580 #define SEM_POST(sem) semaphore_signal(sem);
2581 #else
2582 static sem_t sig_sem;
2583 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
2584 #define SEM_WAIT(sem) sem_wait(&sem);
2585 #define SEM_POST(sem) sem_post(&sem);
2586 #endif
2587
2588 void os::signal_init_pd() {
2589 // Initialize signal structures
2590 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2591
2592 // Initialize signal semaphore
2593 ::SEM_INIT(sig_sem, 0);
2594 }
2595
2596 void os::signal_notify(int sig) {
2597 Atomic::inc(&pending_signals[sig]);
2598 ::SEM_POST(sig_sem);
2599 }
2600
2601 static int check_pending_signals(bool wait) {
2602 Atomic::store(0, &sigint_count);
2603 for (;;) {
2604 for (int i = 0; i < NSIG + 1; i++) {
2605 jint n = pending_signals[i];
2606 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2607 return i;
2608 }
2609 }
2610 if (!wait) {
2611 return -1;
2612 }
2613 JavaThread *thread = JavaThread::current();
2614 ThreadBlockInVM tbivm(thread);
2615
2616 bool threadIsSuspended;
2617 do {
2618 thread->set_suspend_equivalent();
2619 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2620 ::SEM_WAIT(sig_sem);
2621
2622 // were we externally suspended while we were waiting?
2623 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2624 if (threadIsSuspended) {
2625 //
2626 // The semaphore has been incremented, but while we were waiting
2627 // another thread suspended us. We don't want to continue running
2628 // while suspended because that would surprise the thread that
2629 // suspended us.
2630 //
2631 ::SEM_POST(sig_sem);
2632
2633 thread->java_suspend_self();
2634 }
2635 } while (threadIsSuspended);
2636 }
2637 }
2638
2639 int os::signal_lookup() {
2640 return check_pending_signals(false);
2641 }
2642
2643 int os::signal_wait() {
2644 return check_pending_signals(true);
2645 }
2646
2647 ////////////////////////////////////////////////////////////////////////////////
2648 // Virtual Memory
2649
2650 int os::vm_page_size() {
2651 // Seems redundant as all get out
2652 assert(os::Bsd::page_size() != -1, "must call os::init");
2653 return os::Bsd::page_size();
2654 }
2655
2656 // Solaris allocates memory by pages.
2657 int os::vm_allocation_granularity() {
2658 assert(os::Bsd::page_size() != -1, "must call os::init");
2659 return os::Bsd::page_size();
2660 }
2661
2662 // Rationale behind this function:
2663 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2664 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2665 // samples for JITted code. Here we create private executable mapping over the code cache
2666 // and then we can use standard (well, almost, as mapping can change) way to provide
2667 // info for the reporting script by storing timestamp and location of symbol
2668 void bsd_wrap_code(char* base, size_t size) {
2669 static volatile jint cnt = 0;
2670
2671 if (!UseOprofile) {
2672 return;
2673 }
2674
2675 char buf[PATH_MAX + 1];
2676 int num = Atomic::add(1, &cnt);
2677
2678 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2679 os::get_temp_directory(), os::current_process_id(), num);
2680 unlink(buf);
2681
2682 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2683
2684 if (fd != -1) {
2685 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2686 if (rv != (off_t)-1) {
2687 if (::write(fd, "", 1) == 1) {
2688 mmap(base, size,
2689 PROT_READ|PROT_WRITE|PROT_EXEC,
2690 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2691 }
2692 }
2693 ::close(fd);
2694 unlink(buf);
2695 }
2696 }
2697
2698 // NOTE: Bsd kernel does not really reserve the pages for us.
2699 // All it does is to check if there are enough free pages
2700 // left at the time of mmap(). This could be a potential
2701 // problem.
2702 bool os::commit_memory(char* addr, size_t size, bool exec) {
2703 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2704 #ifdef __OpenBSD__
2705 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2706 return ::mprotect(addr, size, prot) == 0;
2707 #else
2708 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2709 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2710 return res != (uintptr_t) MAP_FAILED;
2711 #endif
2712 }
2713
2714 #ifndef _ALLBSD_SOURCE
2715 // Define MAP_HUGETLB here so we can build HotSpot on old systems.
2716 #ifndef MAP_HUGETLB
2717 #define MAP_HUGETLB 0x40000
2718 #endif
2719
2720 // Define MADV_HUGEPAGE here so we can build HotSpot on old systems.
2721 #ifndef MADV_HUGEPAGE
2722 #define MADV_HUGEPAGE 14
2723 #endif
2724 #endif
2725
2726 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
2727 bool exec) {
2728 #ifndef _ALLBSD_SOURCE
2729 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) {
2730 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2731 uintptr_t res =
2732 (uintptr_t) ::mmap(addr, size, prot,
2733 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS|MAP_HUGETLB,
2734 -1, 0);
2735 return res != (uintptr_t) MAP_FAILED;
2736 }
2737 #endif
2738
2739 return commit_memory(addr, size, exec);
2740 }
2741
2742 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2743 #ifndef _ALLBSD_SOURCE
2744 if (UseHugeTLBFS && alignment_hint > (size_t)vm_page_size()) {
2745 // We don't check the return value: madvise(MADV_HUGEPAGE) may not
2746 // be supported or the memory may already be backed by huge pages.
2747 ::madvise(addr, bytes, MADV_HUGEPAGE);
2748 }
2749 #endif
2750 }
2751
2752 void os::free_memory(char *addr, size_t bytes) {
2753 ::madvise(addr, bytes, MADV_DONTNEED);
2754 }
2755
2756 void os::numa_make_global(char *addr, size_t bytes) {
2757 }
2758
2759 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2760 }
2761
2762 bool os::numa_topology_changed() { return false; }
2763
2764 size_t os::numa_get_groups_num() {
2765 return 1;
2766 }
2767
2768 int os::numa_get_group_id() {
2769 return 0;
2770 }
2771
2772 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2773 if (size > 0) {
2774 ids[0] = 0;
2775 return 1;
2776 }
2777 return 0;
2778 }
2779
2780 bool os::get_page_info(char *start, page_info* info) {
2781 return false;
2782 }
2783
2784 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2785 return end;
2786 }
2787
2788 #ifndef _ALLBSD_SOURCE
2789 // Something to do with the numa-aware allocator needs these symbols
2790 extern "C" JNIEXPORT void numa_warn(int number, char *where, ...) { }
2791 extern "C" JNIEXPORT void numa_error(char *where) { }
2792 extern "C" JNIEXPORT int fork1() { return fork(); }
2793
2794
2795 // If we are running with libnuma version > 2, then we should
2796 // be trying to use symbols with versions 1.1
2797 // If we are running with earlier version, which did not have symbol versions,
2798 // we should use the base version.
2799 void* os::Bsd::libnuma_dlsym(void* handle, const char *name) {
2800 void *f = dlvsym(handle, name, "libnuma_1.1");
2801 if (f == NULL) {
2802 f = dlsym(handle, name);
2803 }
2804 return f;
2805 }
2806
2807 bool os::Bsd::libnuma_init() {
2808 // sched_getcpu() should be in libc.
2809 set_sched_getcpu(CAST_TO_FN_PTR(sched_getcpu_func_t,
2810 dlsym(RTLD_DEFAULT, "sched_getcpu")));
2811
2812 if (sched_getcpu() != -1) { // Does it work?
2813 void *handle = dlopen("libnuma.so.1", RTLD_LAZY);
2814 if (handle != NULL) {
2815 set_numa_node_to_cpus(CAST_TO_FN_PTR(numa_node_to_cpus_func_t,
2816 libnuma_dlsym(handle, "numa_node_to_cpus")));
2817 set_numa_max_node(CAST_TO_FN_PTR(numa_max_node_func_t,
2818 libnuma_dlsym(handle, "numa_max_node")));
2819 set_numa_available(CAST_TO_FN_PTR(numa_available_func_t,
2820 libnuma_dlsym(handle, "numa_available")));
2821 set_numa_tonode_memory(CAST_TO_FN_PTR(numa_tonode_memory_func_t,
2822 libnuma_dlsym(handle, "numa_tonode_memory")));
2823 set_numa_interleave_memory(CAST_TO_FN_PTR(numa_interleave_memory_func_t,
2824 libnuma_dlsym(handle, "numa_interleave_memory")));
2825
2826
2827 if (numa_available() != -1) {
2828 set_numa_all_nodes((unsigned long*)libnuma_dlsym(handle, "numa_all_nodes"));
2829 // Create a cpu -> node mapping
2830 _cpu_to_node = new (ResourceObj::C_HEAP) GrowableArray<int>(0, true);
2831 rebuild_cpu_to_node_map();
2832 return true;
2833 }
2834 }
2835 }
2836 return false;
2837 }
2838
2839 // rebuild_cpu_to_node_map() constructs a table mapping cpud id to node id.
2840 // The table is later used in get_node_by_cpu().
2841 void os::Bsd::rebuild_cpu_to_node_map() {
2842 const size_t NCPUS = 32768; // Since the buffer size computation is very obscure
2843 // in libnuma (possible values are starting from 16,
2844 // and continuing up with every other power of 2, but less
2845 // than the maximum number of CPUs supported by kernel), and
2846 // is a subject to change (in libnuma version 2 the requirements
2847 // are more reasonable) we'll just hardcode the number they use
2848 // in the library.
2849 const size_t BitsPerCLong = sizeof(long) * CHAR_BIT;
2850
2851 size_t cpu_num = os::active_processor_count();
2852 size_t cpu_map_size = NCPUS / BitsPerCLong;
2853 size_t cpu_map_valid_size =
2854 MIN2((cpu_num + BitsPerCLong - 1) / BitsPerCLong, cpu_map_size);
2855
2856 cpu_to_node()->clear();
2857 cpu_to_node()->at_grow(cpu_num - 1);
2858 size_t node_num = numa_get_groups_num();
2859
2860 unsigned long *cpu_map = NEW_C_HEAP_ARRAY(unsigned long, cpu_map_size);
2861 for (size_t i = 0; i < node_num; i++) {
2862 if (numa_node_to_cpus(i, cpu_map, cpu_map_size * sizeof(unsigned long)) != -1) {
2863 for (size_t j = 0; j < cpu_map_valid_size; j++) {
2864 if (cpu_map[j] != 0) {
2865 for (size_t k = 0; k < BitsPerCLong; k++) {
2866 if (cpu_map[j] & (1UL << k)) {
2867 cpu_to_node()->at_put(j * BitsPerCLong + k, i);
2868 }
2869 }
2870 }
2871 }
2872 }
2873 }
2874 FREE_C_HEAP_ARRAY(unsigned long, cpu_map);
2875 }
2876
2877 int os::Bsd::get_node_by_cpu(int cpu_id) {
2878 if (cpu_to_node() != NULL && cpu_id >= 0 && cpu_id < cpu_to_node()->length()) {
2879 return cpu_to_node()->at(cpu_id);
2880 }
2881 return -1;
2882 }
2883
2884 GrowableArray<int>* os::Bsd::_cpu_to_node;
2885 os::Bsd::sched_getcpu_func_t os::Bsd::_sched_getcpu;
2886 os::Bsd::numa_node_to_cpus_func_t os::Bsd::_numa_node_to_cpus;
2887 os::Bsd::numa_max_node_func_t os::Bsd::_numa_max_node;
2888 os::Bsd::numa_available_func_t os::Bsd::_numa_available;
2889 os::Bsd::numa_tonode_memory_func_t os::Bsd::_numa_tonode_memory;
2890 os::Bsd::numa_interleave_memory_func_t os::Bsd::_numa_interleave_memory;
2891 unsigned long* os::Bsd::_numa_all_nodes;
2892 #endif
2893
2894 bool os::uncommit_memory(char* addr, size_t size) {
2895 #ifdef __OpenBSD__
2896 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2897 return ::mprotect(addr, size, PROT_NONE) == 0;
2898 #else
2899 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2900 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2901 return res != (uintptr_t) MAP_FAILED;
2902 #endif
2903 }
2904
2905 bool os::create_stack_guard_pages(char* addr, size_t size) {
2906 return os::commit_memory(addr, size);
2907 }
2908
2909 // If this is a growable mapping, remove the guard pages entirely by
2910 // munmap()ping them. If not, just call uncommit_memory().
2911 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2912 return os::uncommit_memory(addr, size);
2913 }
2914
2915 static address _highest_vm_reserved_address = NULL;
2916
2917 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2918 // at 'requested_addr'. If there are existing memory mappings at the same
2919 // location, however, they will be overwritten. If 'fixed' is false,
2920 // 'requested_addr' is only treated as a hint, the return value may or
2921 // may not start from the requested address. Unlike Bsd mmap(), this
2922 // function returns NULL to indicate failure.
2923 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2924 char * addr;
2925 int flags;
2926
2927 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2928 if (fixed) {
2929 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2930 flags |= MAP_FIXED;
2931 }
2932
2933 // Map uncommitted pages PROT_READ and PROT_WRITE, change access
2934 // to PROT_EXEC if executable when we commit the page.
2935 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
2936 flags, -1, 0);
2937
2938 if (addr != MAP_FAILED) {
2939 // anon_mmap() should only get called during VM initialization,
2940 // don't need lock (actually we can skip locking even it can be called
2941 // from multiple threads, because _highest_vm_reserved_address is just a
2942 // hint about the upper limit of non-stack memory regions.)
2943 if ((address)addr + bytes > _highest_vm_reserved_address) {
2944 _highest_vm_reserved_address = (address)addr + bytes;
2945 }
2946 }
2947
2948 return addr == MAP_FAILED ? NULL : addr;
2949 }
2950
2951 // Don't update _highest_vm_reserved_address, because there might be memory
2952 // regions above addr + size. If so, releasing a memory region only creates
2953 // a hole in the address space, it doesn't help prevent heap-stack collision.
2954 //
2955 static int anon_munmap(char * addr, size_t size) {
2956 return ::munmap(addr, size) == 0;
2957 }
2958
2959 char* os::reserve_memory(size_t bytes, char* requested_addr,
2960 size_t alignment_hint) {
2961 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2962 }
2963
2964 bool os::release_memory(char* addr, size_t size) {
2965 return anon_munmap(addr, size);
2966 }
2967
2968 static address highest_vm_reserved_address() {
2969 return _highest_vm_reserved_address;
2970 }
2971
2972 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2973 // Bsd wants the mprotect address argument to be page aligned.
2974 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2975
2976 // According to SUSv3, mprotect() should only be used with mappings
2977 // established by mmap(), and mmap() always maps whole pages. Unaligned
2978 // 'addr' likely indicates problem in the VM (e.g. trying to change
2979 // protection of malloc'ed or statically allocated memory). Check the
2980 // caller if you hit this assert.
2981 assert(addr == bottom, "sanity check");
2982
2983 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2984 return ::mprotect(bottom, size, prot) == 0;
2985 }
2986
2987 // Set protections specified
2988 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2989 bool is_committed) {
2990 unsigned int p = 0;
2991 switch (prot) {
2992 case MEM_PROT_NONE: p = PROT_NONE; break;
2993 case MEM_PROT_READ: p = PROT_READ; break;
2994 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2995 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2996 default:
2997 ShouldNotReachHere();
2998 }
2999 // is_committed is unused.
3000 return bsd_mprotect(addr, bytes, p);
3001 }
3002
3003 bool os::guard_memory(char* addr, size_t size) {
3004 return bsd_mprotect(addr, size, PROT_NONE);
3005 }
3006
3007 bool os::unguard_memory(char* addr, size_t size) {
3008 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
3009 }
3010
3011 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
3012 bool result = false;
3013 #ifndef _ALLBSD_SOURCE
3014 void *p = mmap (NULL, page_size, PROT_READ|PROT_WRITE,
3015 MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB,
3016 -1, 0);
3017
3018 if (p != (void *) -1) {
3019 // We don't know if this really is a huge page or not.
3020 FILE *fp = fopen("/proc/self/maps", "r");
3021 if (fp) {
3022 while (!feof(fp)) {
3023 char chars[257];
3024 long x = 0;
3025 if (fgets(chars, sizeof(chars), fp)) {
3026 if (sscanf(chars, "%lx-%*x", &x) == 1
3027 && x == (long)p) {
3028 if (strstr (chars, "hugepage")) {
3029 result = true;
3030 break;
3031 }
3032 }
3033 }
3034 }
3035 fclose(fp);
3036 }
3037 munmap (p, page_size);
3038 if (result)
3039 return true;
3040 }
3041
3042 if (warn) {
3043 warning("HugeTLBFS is not supported by the operating system.");
3044 }
3045 #endif
3046
3047 return result;
3048 }
3049
3050 /*
3051 * Set the coredump_filter bits to include largepages in core dump (bit 6)
3052 *
3053 * From the coredump_filter documentation:
3054 *
3055 * - (bit 0) anonymous private memory
3056 * - (bit 1) anonymous shared memory
3057 * - (bit 2) file-backed private memory
3058 * - (bit 3) file-backed shared memory
3059 * - (bit 4) ELF header pages in file-backed private memory areas (it is
3060 * effective only if the bit 2 is cleared)
3061 * - (bit 5) hugetlb private memory
3062 * - (bit 6) hugetlb shared memory
3063 */
3064 static void set_coredump_filter(void) {
3065 FILE *f;
3066 long cdm;
3067
3068 if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
3069 return;
3070 }
3071
3072 if (fscanf(f, "%lx", &cdm) != 1) {
3073 fclose(f);
3074 return;
3075 }
3076
3077 rewind(f);
3078
3079 if ((cdm & LARGEPAGES_BIT) == 0) {
3080 cdm |= LARGEPAGES_BIT;
3081 fprintf(f, "%#lx", cdm);
3082 }
3083
3084 fclose(f);
3085 }
3086
3087 // Large page support
3088
3089 static size_t _large_page_size = 0;
3090
3091 void os::large_page_init() {
3092 #ifndef _ALLBSD_SOURCE
3093 if (!UseLargePages) {
3094 UseHugeTLBFS = false;
3095 UseSHM = false;
3096 return;
3097 }
3098
3099 if (FLAG_IS_DEFAULT(UseHugeTLBFS) && FLAG_IS_DEFAULT(UseSHM)) {
3100 // If UseLargePages is specified on the command line try both methods,
3101 // if it's default, then try only HugeTLBFS.
3102 if (FLAG_IS_DEFAULT(UseLargePages)) {
3103 UseHugeTLBFS = true;
3104 } else {
3105 UseHugeTLBFS = UseSHM = true;
3106 }
3107 }
3108
3109 if (LargePageSizeInBytes) {
3110 _large_page_size = LargePageSizeInBytes;
3111 } else {
3112 // large_page_size on Bsd is used to round up heap size. x86 uses either
3113 // 2M or 4M page, depending on whether PAE (Physical Address Extensions)
3114 // mode is enabled. AMD64/EM64T uses 2M page in 64bit mode. IA64 can use
3115 // page as large as 256M.
3116 //
3117 // Here we try to figure out page size by parsing /proc/meminfo and looking
3118 // for a line with the following format:
3119 // Hugepagesize: 2048 kB
3120 //
3121 // If we can't determine the value (e.g. /proc is not mounted, or the text
3122 // format has been changed), we'll use the largest page size supported by
3123 // the processor.
3124
3125 #ifndef ZERO
3126 _large_page_size = IA32_ONLY(4 * M) AMD64_ONLY(2 * M) IA64_ONLY(256 * M) SPARC_ONLY(4 * M)
3127 ARM_ONLY(2 * M) PPC_ONLY(4 * M);
3128 #endif // ZERO
3129
3130 FILE *fp = fopen("/proc/meminfo", "r");
3131 if (fp) {
3132 while (!feof(fp)) {
3133 int x = 0;
3134 char buf[16];
3135 if (fscanf(fp, "Hugepagesize: %d", &x) == 1) {
3136 if (x && fgets(buf, sizeof(buf), fp) && strcmp(buf, " kB\n") == 0) {
3137 _large_page_size = x * K;
3138 break;
3139 }
3140 } else {
3141 // skip to next line
3142 for (;;) {
3143 int ch = fgetc(fp);
3144 if (ch == EOF || ch == (int)'\n') break;
3145 }
3146 }
3147 }
3148 fclose(fp);
3149 }
3150 }
3151
3152 // print a warning if any large page related flag is specified on command line
3153 bool warn_on_failure = !FLAG_IS_DEFAULT(UseHugeTLBFS);
3154
3155 const size_t default_page_size = (size_t)Bsd::page_size();
3156 if (_large_page_size > default_page_size) {
3157 _page_sizes[0] = _large_page_size;
3158 _page_sizes[1] = default_page_size;
3159 _page_sizes[2] = 0;
3160 }
3161 UseHugeTLBFS = UseHugeTLBFS &&
3162 Bsd::hugetlbfs_sanity_check(warn_on_failure, _large_page_size);
3163
3164 if (UseHugeTLBFS)
3165 UseSHM = false;
3166
3167 UseLargePages = UseHugeTLBFS || UseSHM;
3168
3169 set_coredump_filter();
3170 #endif
3171 }
3172
3173 #ifndef _ALLBSD_SOURCE
3174 #ifndef SHM_HUGETLB
3175 #define SHM_HUGETLB 04000
3176 #endif
3177 #endif
3178
3179 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
3180 // "exec" is passed in but not used. Creating the shared image for
3181 // the code cache doesn't have an SHM_X executable permission to check.
3182 assert(UseLargePages && UseSHM, "only for SHM large pages");
3183
3184 key_t key = IPC_PRIVATE;
3185 char *addr;
3186
3187 bool warn_on_failure = UseLargePages &&
3188 (!FLAG_IS_DEFAULT(UseLargePages) ||
3189 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
3190 );
3191 char msg[128];
3192
3193 // Create a large shared memory region to attach to based on size.
3194 // Currently, size is the total size of the heap
3195 #ifndef _ALLBSD_SOURCE
3196 int shmid = shmget(key, bytes, SHM_HUGETLB|IPC_CREAT|SHM_R|SHM_W);
3197 #else
3198 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
3199 #endif
3200 if (shmid == -1) {
3201 // Possible reasons for shmget failure:
3202 // 1. shmmax is too small for Java heap.
3203 // > check shmmax value: cat /proc/sys/kernel/shmmax
3204 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
3205 // 2. not enough large page memory.
3206 // > check available large pages: cat /proc/meminfo
3207 // > increase amount of large pages:
3208 // echo new_value > /proc/sys/vm/nr_hugepages
3209 // Note 1: different Bsd may use different name for this property,
3210 // e.g. on Redhat AS-3 it is "hugetlb_pool".
3211 // Note 2: it's possible there's enough physical memory available but
3212 // they are so fragmented after a long run that they can't
3213 // coalesce into large pages. Try to reserve large pages when
3214 // the system is still "fresh".
3215 if (warn_on_failure) {
3216 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
3217 warning(msg);
3218 }
3219 return NULL;
3220 }
3221
3222 // attach to the region
3223 addr = (char*)shmat(shmid, req_addr, 0);
3224 int err = errno;
3225
3226 // Remove shmid. If shmat() is successful, the actual shared memory segment
3227 // will be deleted when it's detached by shmdt() or when the process
3228 // terminates. If shmat() is not successful this will remove the shared
3229 // segment immediately.
3230 shmctl(shmid, IPC_RMID, NULL);
3231
3232 if ((intptr_t)addr == -1) {
3233 if (warn_on_failure) {
3234 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
3235 warning(msg);
3236 }
3237 return NULL;
3238 }
3239
3240 return addr;
3241 }
3242
3243 bool os::release_memory_special(char* base, size_t bytes) {
3244 // detaching the SHM segment will also delete it, see reserve_memory_special()
3245 int rslt = shmdt(base);
3246 return rslt == 0;
3247 }
3248
3249 size_t os::large_page_size() {
3250 return _large_page_size;
3251 }
3252
3253 // HugeTLBFS allows application to commit large page memory on demand;
3254 // with SysV SHM the entire memory region must be allocated as shared
3255 // memory.
3256 bool os::can_commit_large_page_memory() {
3257 return UseHugeTLBFS;
3258 }
3259
3260 bool os::can_execute_large_page_memory() {
3261 return UseHugeTLBFS;
3262 }
3263
3264 // Reserve memory at an arbitrary address, only if that area is
3265 // available (and not reserved for something else).
3266
3267 char* os::attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
3268 const int max_tries = 10;
3269 char* base[max_tries];
3270 size_t size[max_tries];
3271 const size_t gap = 0x000000;
3272
3273 // Assert only that the size is a multiple of the page size, since
3274 // that's all that mmap requires, and since that's all we really know
3275 // about at this low abstraction level. If we need higher alignment,
3276 // we can either pass an alignment to this method or verify alignment
3277 // in one of the methods further up the call chain. See bug 5044738.
3278 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
3279
3280 // Repeatedly allocate blocks until the block is allocated at the
3281 // right spot. Give up after max_tries. Note that reserve_memory() will
3282 // automatically update _highest_vm_reserved_address if the call is
3283 // successful. The variable tracks the highest memory address every reserved
3284 // by JVM. It is used to detect heap-stack collision if running with
3285 // fixed-stack BsdThreads. Because here we may attempt to reserve more
3286 // space than needed, it could confuse the collision detecting code. To
3287 // solve the problem, save current _highest_vm_reserved_address and
3288 // calculate the correct value before return.
3289 address old_highest = _highest_vm_reserved_address;
3290
3291 // Bsd mmap allows caller to pass an address as hint; give it a try first,
3292 // if kernel honors the hint then we can return immediately.
3293 char * addr = anon_mmap(requested_addr, bytes, false);
3294 if (addr == requested_addr) {
3295 return requested_addr;
3296 }
3297
3298 if (addr != NULL) {
3299 // mmap() is successful but it fails to reserve at the requested address
3300 anon_munmap(addr, bytes);
3301 }
3302
3303 int i;
3304 for (i = 0; i < max_tries; ++i) {
3305 base[i] = reserve_memory(bytes);
3306
3307 if (base[i] != NULL) {
3308 // Is this the block we wanted?
3309 if (base[i] == requested_addr) {
3310 size[i] = bytes;
3311 break;
3312 }
3313
3314 // Does this overlap the block we wanted? Give back the overlapped
3315 // parts and try again.
3316
3317 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
3318 if (top_overlap >= 0 && top_overlap < bytes) {
3319 unmap_memory(base[i], top_overlap);
3320 base[i] += top_overlap;
3321 size[i] = bytes - top_overlap;
3322 } else {
3323 size_t bottom_overlap = base[i] + bytes - requested_addr;
3324 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
3325 unmap_memory(requested_addr, bottom_overlap);
3326 size[i] = bytes - bottom_overlap;
3327 } else {
3328 size[i] = bytes;
3329 }
3330 }
3331 }
3332 }
3333
3334 // Give back the unused reserved pieces.
3335
3336 for (int j = 0; j < i; ++j) {
3337 if (base[j] != NULL) {
3338 unmap_memory(base[j], size[j]);
3339 }
3340 }
3341
3342 if (i < max_tries) {
3343 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
3344 return requested_addr;
3345 } else {
3346 _highest_vm_reserved_address = old_highest;
3347 return NULL;
3348 }
3349 }
3350
3351 size_t os::read(int fd, void *buf, unsigned int nBytes) {
3352 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
3353 }
3354
3355 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
3356 // Solaris uses poll(), bsd uses park().
3357 // Poll() is likely a better choice, assuming that Thread.interrupt()
3358 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
3359 // SIGSEGV, see 4355769.
3360
3361 const int NANOSECS_PER_MILLISECS = 1000000;
3362
3363 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
3364 assert(thread == Thread::current(), "thread consistency check");
3365
3366 ParkEvent * const slp = thread->_SleepEvent ;
3367 slp->reset() ;
3368 OrderAccess::fence() ;
3369
3370 if (interruptible) {
3371 jlong prevtime = javaTimeNanos();
3372
3373 for (;;) {
3374 if (os::is_interrupted(thread, true)) {
3375 return OS_INTRPT;
3376 }
3377
3378 jlong newtime = javaTimeNanos();
3379
3380 if (newtime - prevtime < 0) {
3381 // time moving backwards, should only happen if no monotonic clock
3382 // not a guarantee() because JVM should not abort on kernel/glibc bugs
3383 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
3384 } else {
3385 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISECS;
3386 }
3387
3388 if(millis <= 0) {
3389 return OS_OK;
3390 }
3391
3392 prevtime = newtime;
3393
3394 {
3395 assert(thread->is_Java_thread(), "sanity check");
3396 JavaThread *jt = (JavaThread *) thread;
3397 ThreadBlockInVM tbivm(jt);
3398 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
3399
3400 jt->set_suspend_equivalent();
3401 // cleared by handle_special_suspend_equivalent_condition() or
3402 // java_suspend_self() via check_and_wait_while_suspended()
3403
3404 slp->park(millis);
3405
3406 // were we externally suspended while we were waiting?
3407 jt->check_and_wait_while_suspended();
3408 }
3409 }
3410 } else {
3411 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
3412 jlong prevtime = javaTimeNanos();
3413
3414 for (;;) {
3415 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
3416 // the 1st iteration ...
3417 jlong newtime = javaTimeNanos();
3418
3419 if (newtime - prevtime < 0) {
3420 // time moving backwards, should only happen if no monotonic clock
3421 // not a guarantee() because JVM should not abort on kernel/glibc bugs
3422 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
3423 } else {
3424 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISECS;
3425 }
3426
3427 if(millis <= 0) break ;
3428
3429 prevtime = newtime;
3430 slp->park(millis);
3431 }
3432 return OS_OK ;
3433 }
3434 }
3435
3436 int os::naked_sleep() {
3437 // %% make the sleep time an integer flag. for now use 1 millisec.
3438 return os::sleep(Thread::current(), 1, false);
3439 }
3440
3441 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
3442 void os::infinite_sleep() {
3443 while (true) { // sleep forever ...
3444 ::sleep(100); // ... 100 seconds at a time
3445 }
3446 }
3447
3448 // Used to convert frequent JVM_Yield() to nops
3449 bool os::dont_yield() {
3450 return DontYieldALot;
3451 }
3452
3453 void os::yield() {
3454 sched_yield();
3455 }
3456
3457 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
3458
3459 void os::yield_all(int attempts) {
3460 // Yields to all threads, including threads with lower priorities
3461 // Threads on Bsd are all with same priority. The Solaris style
3462 // os::yield_all() with nanosleep(1ms) is not necessary.
3463 sched_yield();
3464 }
3465
3466 // Called from the tight loops to possibly influence time-sharing heuristics
3467 void os::loop_breaker(int attempts) {
3468 os::yield_all(attempts);
3469 }
3470
3471 ////////////////////////////////////////////////////////////////////////////////
3472 // thread priority support
3473
3474 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
3475 // only supports dynamic priority, static priority must be zero. For real-time
3476 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
3477 // However, for large multi-threaded applications, SCHED_RR is not only slower
3478 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
3479 // of 5 runs - Sep 2005).
3480 //
3481 // The following code actually changes the niceness of kernel-thread/LWP. It
3482 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
3483 // not the entire user process, and user level threads are 1:1 mapped to kernel
3484 // threads. It has always been the case, but could change in the future. For
3485 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
3486 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
3487
3488 #if defined(_ALLBSD_SOURCE) && !defined(__APPLE__)
3489 int os::java_to_os_priority[MaxPriority + 1] = {
3490 19, // 0 Entry should never be used
3491
3492 0, // 1 MinPriority
3493 3, // 2
3494 6, // 3
3495
3496 10, // 4
3497 15, // 5 NormPriority
3498 18, // 6
3499
3500 21, // 7
3501 25, // 8
3502 28, // 9 NearMaxPriority
3503
3504 31 // 10 MaxPriority
3505 };
3506 #elif defined(__APPLE__)
3507 /* Using Mach high-level priority assignments */
3508 int os::java_to_os_priority[MaxPriority + 1] = {
3509 0, // 0 Entry should never be used (MINPRI_USER)
3510
3511 27, // 1 MinPriority
3512 28, // 2
3513 29, // 3
3514
3515 30, // 4
3516 31, // 5 NormPriority (BASEPRI_DEFAULT)
3517 32, // 6
3518
3519 33, // 7
3520 34, // 8
3521 35, // 9 NearMaxPriority
3522
3523 36 // 10 MaxPriority
3524 };
3525 #else
3526 int os::java_to_os_priority[MaxPriority + 1] = {
3527 19, // 0 Entry should never be used
3528
3529 4, // 1 MinPriority
3530 3, // 2
3531 2, // 3
3532
3533 1, // 4
3534 0, // 5 NormPriority
3535 -1, // 6
3536
3537 -2, // 7
3538 -3, // 8
3539 -4, // 9 NearMaxPriority
3540
3541 -5 // 10 MaxPriority
3542 };
3543 #endif
3544
3545 static int prio_init() {
3546 if (ThreadPriorityPolicy == 1) {
3547 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
3548 // if effective uid is not root. Perhaps, a more elegant way of doing
3549 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
3550 if (geteuid() != 0) {
3551 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
3552 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
3553 }
3554 ThreadPriorityPolicy = 0;
3555 }
3556 }
3557 return 0;
3558 }
3559
3560 OSReturn os::set_native_priority(Thread* thread, int newpri) {
3561 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
3562
3563 #ifdef __OpenBSD__
3564 // OpenBSD pthread_setprio starves low priority threads
3565 return OS_OK;
3566 #elif defined(__FreeBSD__)
3567 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
3568 #elif defined(__APPLE__) || defined(__NetBSD__)
3569 struct sched_param sp;
3570 int policy;
3571 pthread_t self = pthread_self();
3572
3573 if (pthread_getschedparam(self, &policy, &sp) != 0)
3574 return OS_ERR;
3575
3576 sp.sched_priority = newpri;
3577 if (pthread_setschedparam(self, policy, &sp) != 0)
3578 return OS_ERR;
3579
3580 return OS_OK;
3581 #else
3582 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
3583 return (ret == 0) ? OS_OK : OS_ERR;
3584 #endif
3585 }
3586
3587 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
3588 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
3589 *priority_ptr = java_to_os_priority[NormPriority];
3590 return OS_OK;
3591 }
3592
3593 errno = 0;
3594 #if defined(__OpenBSD__) || defined(__FreeBSD__)
3595 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
3596 #elif defined(__APPLE__) || defined(__NetBSD__)
3597 int policy;
3598 struct sched_param sp;
3599
3600 pthread_getschedparam(pthread_self(), &policy, &sp);
3601 *priority_ptr = sp.sched_priority;
3602 #else
3603 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
3604 #endif
3605 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
3606 }
3607
3608 // Hint to the underlying OS that a task switch would not be good.
3609 // Void return because it's a hint and can fail.
3610 void os::hint_no_preempt() {}
3611
3612 ////////////////////////////////////////////////////////////////////////////////
3613 // suspend/resume support
3614
3615 // the low-level signal-based suspend/resume support is a remnant from the
3616 // old VM-suspension that used to be for java-suspension, safepoints etc,
3617 // within hotspot. Now there is a single use-case for this:
3618 // - calling get_thread_pc() on the VMThread by the flat-profiler task
3619 // that runs in the watcher thread.
3620 // The remaining code is greatly simplified from the more general suspension
3621 // code that used to be used.
3622 //
3623 // The protocol is quite simple:
3624 // - suspend:
3625 // - sends a signal to the target thread
3626 // - polls the suspend state of the osthread using a yield loop
3627 // - target thread signal handler (SR_handler) sets suspend state
3628 // and blocks in sigsuspend until continued
3629 // - resume:
3630 // - sets target osthread state to continue
3631 // - sends signal to end the sigsuspend loop in the SR_handler
3632 //
3633 // Note that the SR_lock plays no role in this suspend/resume protocol.
3634 //
3635
3636 static void resume_clear_context(OSThread *osthread) {
3637 osthread->set_ucontext(NULL);
3638 osthread->set_siginfo(NULL);
3639
3640 // notify the suspend action is completed, we have now resumed
3641 osthread->sr.clear_suspended();
3642 }
3643
3644 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
3645 osthread->set_ucontext(context);
3646 osthread->set_siginfo(siginfo);
3647 }
3648
3649 //
3650 // Handler function invoked when a thread's execution is suspended or
3651 // resumed. We have to be careful that only async-safe functions are
3652 // called here (Note: most pthread functions are not async safe and
3653 // should be avoided.)
3654 //
3655 // Note: sigwait() is a more natural fit than sigsuspend() from an
3656 // interface point of view, but sigwait() prevents the signal hander
3657 // from being run. libpthread would get very confused by not having
3658 // its signal handlers run and prevents sigwait()'s use with the
3659 // mutex granting granting signal.
3660 //
3661 // Currently only ever called on the VMThread
3662 //
3663 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
3664 // Save and restore errno to avoid confusing native code with EINTR
3665 // after sigsuspend.
3666 int old_errno = errno;
3667
3668 Thread* thread = Thread::current();
3669 OSThread* osthread = thread->osthread();
3670 assert(thread->is_VM_thread(), "Must be VMThread");
3671 // read current suspend action
3672 int action = osthread->sr.suspend_action();
3673 if (action == SR_SUSPEND) {
3674 suspend_save_context(osthread, siginfo, context);
3675
3676 // Notify the suspend action is about to be completed. do_suspend()
3677 // waits until SR_SUSPENDED is set and then returns. We will wait
3678 // here for a resume signal and that completes the suspend-other
3679 // action. do_suspend/do_resume is always called as a pair from
3680 // the same thread - so there are no races
3681
3682 // notify the caller
3683 osthread->sr.set_suspended();
3684
3685 sigset_t suspend_set; // signals for sigsuspend()
3686
3687 // get current set of blocked signals and unblock resume signal
3688 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
3689 sigdelset(&suspend_set, SR_signum);
3690
3691 // wait here until we are resumed
3692 do {
3693 sigsuspend(&suspend_set);
3694 // ignore all returns until we get a resume signal
3695 } while (osthread->sr.suspend_action() != SR_CONTINUE);
3696
3697 resume_clear_context(osthread);
3698
3699 } else {
3700 assert(action == SR_CONTINUE, "unexpected sr action");
3701 // nothing special to do - just leave the handler
3702 }
3703
3704 errno = old_errno;
3705 }
3706
3707
3708 static int SR_initialize() {
3709 struct sigaction act;
3710 char *s;
3711 /* Get signal number to use for suspend/resume */
3712 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
3713 int sig = ::strtol(s, 0, 10);
3714 if (sig > 0 || sig < NSIG) {
3715 SR_signum = sig;
3716 }
3717 }
3718
3719 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
3720 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
3721
3722 sigemptyset(&SR_sigset);
3723 sigaddset(&SR_sigset, SR_signum);
3724
3725 /* Set up signal handler for suspend/resume */
3726 act.sa_flags = SA_RESTART|SA_SIGINFO;
3727 act.sa_handler = (void (*)(int)) SR_handler;
3728
3729 // SR_signum is blocked by default.
3730 // 4528190 - We also need to block pthread restart signal (32 on all
3731 // supported Bsd platforms). Note that BsdThreads need to block
3732 // this signal for all threads to work properly. So we don't have
3733 // to use hard-coded signal number when setting up the mask.
3734 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
3735
3736 if (sigaction(SR_signum, &act, 0) == -1) {
3737 return -1;
3738 }
3739
3740 // Save signal flag
3741 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
3742 return 0;
3743 }
3744
3745 static int SR_finalize() {
3746 return 0;
3747 }
3748
3749
3750 // returns true on success and false on error - really an error is fatal
3751 // but this seems the normal response to library errors
3752 static bool do_suspend(OSThread* osthread) {
3753 // mark as suspended and send signal
3754 osthread->sr.set_suspend_action(SR_SUSPEND);
3755 int status = pthread_kill(osthread->pthread_id(), SR_signum);
3756 assert_status(status == 0, status, "pthread_kill");
3757
3758 // check status and wait until notified of suspension
3759 if (status == 0) {
3760 for (int i = 0; !osthread->sr.is_suspended(); i++) {
3761 os::yield_all(i);
3762 }
3763 osthread->sr.set_suspend_action(SR_NONE);
3764 return true;
3765 }
3766 else {
3767 osthread->sr.set_suspend_action(SR_NONE);
3768 return false;
3769 }
3770 }
3771
3772 static void do_resume(OSThread* osthread) {
3773 assert(osthread->sr.is_suspended(), "thread should be suspended");
3774 osthread->sr.set_suspend_action(SR_CONTINUE);
3775
3776 int status = pthread_kill(osthread->pthread_id(), SR_signum);
3777 assert_status(status == 0, status, "pthread_kill");
3778 // check status and wait unit notified of resumption
3779 if (status == 0) {
3780 for (int i = 0; osthread->sr.is_suspended(); i++) {
3781 os::yield_all(i);
3782 }
3783 }
3784 osthread->sr.set_suspend_action(SR_NONE);
3785 }
3786
3787 ////////////////////////////////////////////////////////////////////////////////
3788 // interrupt support
3789
3790 void os::interrupt(Thread* thread) {
3791 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3792 "possibility of dangling Thread pointer");
3793
3794 OSThread* osthread = thread->osthread();
3795
3796 if (!osthread->interrupted()) {
3797 osthread->set_interrupted(true);
3798 // More than one thread can get here with the same value of osthread,
3799 // resulting in multiple notifications. We do, however, want the store
3800 // to interrupted() to be visible to other threads before we execute unpark().
3801 OrderAccess::fence();
3802 ParkEvent * const slp = thread->_SleepEvent ;
3803 if (slp != NULL) slp->unpark() ;
3804 }
3805
3806 // For JSR166. Unpark even if interrupt status already was set
3807 if (thread->is_Java_thread())
3808 ((JavaThread*)thread)->parker()->unpark();
3809
3810 ParkEvent * ev = thread->_ParkEvent ;
3811 if (ev != NULL) ev->unpark() ;
3812
3813 }
3814
3815 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3816 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3817 "possibility of dangling Thread pointer");
3818
3819 OSThread* osthread = thread->osthread();
3820
3821 bool interrupted = osthread->interrupted();
3822
3823 if (interrupted && clear_interrupted) {
3824 osthread->set_interrupted(false);
3825 // consider thread->_SleepEvent->reset() ... optional optimization
3826 }
3827
3828 return interrupted;
3829 }
3830
3831 ///////////////////////////////////////////////////////////////////////////////////
3832 // signal handling (except suspend/resume)
3833
3834 // This routine may be used by user applications as a "hook" to catch signals.
3835 // The user-defined signal handler must pass unrecognized signals to this
3836 // routine, and if it returns true (non-zero), then the signal handler must
3837 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3838 // routine will never retun false (zero), but instead will execute a VM panic
3839 // routine kill the process.
3840 //
3841 // If this routine returns false, it is OK to call it again. This allows
3842 // the user-defined signal handler to perform checks either before or after
3843 // the VM performs its own checks. Naturally, the user code would be making
3844 // a serious error if it tried to handle an exception (such as a null check
3845 // or breakpoint) that the VM was generating for its own correct operation.
3846 //
3847 // This routine may recognize any of the following kinds of signals:
3848 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3849 // It should be consulted by handlers for any of those signals.
3850 //
3851 // The caller of this routine must pass in the three arguments supplied
3852 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3853 // field of the structure passed to sigaction(). This routine assumes that
3854 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3855 //
3856 // Note that the VM will print warnings if it detects conflicting signal
3857 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3858 //
3859 extern "C" JNIEXPORT int
3860 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3861 void* ucontext, int abort_if_unrecognized);
3862
3863 void signalHandler(int sig, siginfo_t* info, void* uc) {
3864 assert(info != NULL && uc != NULL, "it must be old kernel");
3865 JVM_handle_bsd_signal(sig, info, uc, true);
3866 }
3867
3868
3869 // This boolean allows users to forward their own non-matching signals
3870 // to JVM_handle_bsd_signal, harmlessly.
3871 bool os::Bsd::signal_handlers_are_installed = false;
3872
3873 // For signal-chaining
3874 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3875 unsigned int os::Bsd::sigs = 0;
3876 bool os::Bsd::libjsig_is_loaded = false;
3877 typedef struct sigaction *(*get_signal_t)(int);
3878 get_signal_t os::Bsd::get_signal_action = NULL;
3879
3880 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3881 struct sigaction *actp = NULL;
3882
3883 if (libjsig_is_loaded) {
3884 // Retrieve the old signal handler from libjsig
3885 actp = (*get_signal_action)(sig);
3886 }
3887 if (actp == NULL) {
3888 // Retrieve the preinstalled signal handler from jvm
3889 actp = get_preinstalled_handler(sig);
3890 }
3891
3892 return actp;
3893 }
3894
3895 static bool call_chained_handler(struct sigaction *actp, int sig,
3896 siginfo_t *siginfo, void *context) {
3897 // Call the old signal handler
3898 if (actp->sa_handler == SIG_DFL) {
3899 // It's more reasonable to let jvm treat it as an unexpected exception
3900 // instead of taking the default action.
3901 return false;
3902 } else if (actp->sa_handler != SIG_IGN) {
3903 if ((actp->sa_flags & SA_NODEFER) == 0) {
3904 // automaticlly block the signal
3905 sigaddset(&(actp->sa_mask), sig);
3906 }
3907
3908 sa_handler_t hand;
3909 sa_sigaction_t sa;
3910 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3911 // retrieve the chained handler
3912 if (siginfo_flag_set) {
3913 sa = actp->sa_sigaction;
3914 } else {
3915 hand = actp->sa_handler;
3916 }
3917
3918 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3919 actp->sa_handler = SIG_DFL;
3920 }
3921
3922 // try to honor the signal mask
3923 sigset_t oset;
3924 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3925
3926 // call into the chained handler
3927 if (siginfo_flag_set) {
3928 (*sa)(sig, siginfo, context);
3929 } else {
3930 (*hand)(sig);
3931 }
3932
3933 // restore the signal mask
3934 pthread_sigmask(SIG_SETMASK, &oset, 0);
3935 }
3936 // Tell jvm's signal handler the signal is taken care of.
3937 return true;
3938 }
3939
3940 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3941 bool chained = false;
3942 // signal-chaining
3943 if (UseSignalChaining) {
3944 struct sigaction *actp = get_chained_signal_action(sig);
3945 if (actp != NULL) {
3946 chained = call_chained_handler(actp, sig, siginfo, context);
3947 }
3948 }
3949 return chained;
3950 }
3951
3952 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3953 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3954 return &sigact[sig];
3955 }
3956 return NULL;
3957 }
3958
3959 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3960 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3961 sigact[sig] = oldAct;
3962 sigs |= (unsigned int)1 << sig;
3963 }
3964
3965 // for diagnostic
3966 int os::Bsd::sigflags[MAXSIGNUM];
3967
3968 int os::Bsd::get_our_sigflags(int sig) {
3969 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3970 return sigflags[sig];
3971 }
3972
3973 void os::Bsd::set_our_sigflags(int sig, int flags) {
3974 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3975 sigflags[sig] = flags;
3976 }
3977
3978 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3979 // Check for overwrite.
3980 struct sigaction oldAct;
3981 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3982
3983 void* oldhand = oldAct.sa_sigaction
3984 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3985 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3986 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3987 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3988 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3989 if (AllowUserSignalHandlers || !set_installed) {
3990 // Do not overwrite; user takes responsibility to forward to us.
3991 return;
3992 } else if (UseSignalChaining) {
3993 // save the old handler in jvm
3994 save_preinstalled_handler(sig, oldAct);
3995 // libjsig also interposes the sigaction() call below and saves the
3996 // old sigaction on it own.
3997 } else {
3998 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3999 "%#lx for signal %d.", (long)oldhand, sig));
4000 }
4001 }
4002
4003 struct sigaction sigAct;
4004 sigfillset(&(sigAct.sa_mask));
4005 sigAct.sa_handler = SIG_DFL;
4006 if (!set_installed) {
4007 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
4008 } else {
4009 sigAct.sa_sigaction = signalHandler;
4010 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
4011 }
4012 // Save flags, which are set by ours
4013 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
4014 sigflags[sig] = sigAct.sa_flags;
4015
4016 int ret = sigaction(sig, &sigAct, &oldAct);
4017 assert(ret == 0, "check");
4018
4019 void* oldhand2 = oldAct.sa_sigaction
4020 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
4021 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
4022 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
4023 }
4024
4025 // install signal handlers for signals that HotSpot needs to
4026 // handle in order to support Java-level exception handling.
4027
4028 void os::Bsd::install_signal_handlers() {
4029 if (!signal_handlers_are_installed) {
4030 signal_handlers_are_installed = true;
4031
4032 // signal-chaining
4033 typedef void (*signal_setting_t)();
4034 signal_setting_t begin_signal_setting = NULL;
4035 signal_setting_t end_signal_setting = NULL;
4036 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
4037 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
4038 if (begin_signal_setting != NULL) {
4039 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
4040 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
4041 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
4042 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
4043 libjsig_is_loaded = true;
4044 assert(UseSignalChaining, "should enable signal-chaining");
4045 }
4046 if (libjsig_is_loaded) {
4047 // Tell libjsig jvm is setting signal handlers
4048 (*begin_signal_setting)();
4049 }
4050
4051 set_signal_handler(SIGSEGV, true);
4052 set_signal_handler(SIGPIPE, true);
4053 set_signal_handler(SIGBUS, true);
4054 set_signal_handler(SIGILL, true);
4055 set_signal_handler(SIGFPE, true);
4056 set_signal_handler(SIGXFSZ, true);
4057
4058 #if defined(__APPLE__)
4059 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
4060 // signals caught and handled by the JVM. To work around this, we reset the mach task
4061 // signal handler that's placed on our process by CrashReporter. This disables
4062 // CrashReporter-based reporting.
4063 //
4064 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
4065 // on caught fatal signals.
4066 //
4067 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
4068 // handlers. By replacing the existing task exception handler, we disable gdb's mach
4069 // exception handling, while leaving the standard BSD signal handlers functional.
4070 kern_return_t kr;
4071 kr = task_set_exception_ports(mach_task_self(),
4072 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
4073 MACH_PORT_NULL,
4074 EXCEPTION_STATE_IDENTITY,
4075 MACHINE_THREAD_STATE);
4076
4077 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
4078 #endif
4079
4080 if (libjsig_is_loaded) {
4081 // Tell libjsig jvm finishes setting signal handlers
4082 (*end_signal_setting)();
4083 }
4084
4085 // We don't activate signal checker if libjsig is in place, we trust ourselves
4086 // and if UserSignalHandler is installed all bets are off
4087 if (CheckJNICalls) {
4088 if (libjsig_is_loaded) {
4089 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
4090 check_signals = false;
4091 }
4092 if (AllowUserSignalHandlers) {
4093 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
4094 check_signals = false;
4095 }
4096 }
4097 }
4098 }
4099
4100 #ifndef _ALLBSD_SOURCE
4101 // This is the fastest way to get thread cpu time on Bsd.
4102 // Returns cpu time (user+sys) for any thread, not only for current.
4103 // POSIX compliant clocks are implemented in the kernels 2.6.16+.
4104 // It might work on 2.6.10+ with a special kernel/glibc patch.
4105 // For reference, please, see IEEE Std 1003.1-2004:
4106 // http://www.unix.org/single_unix_specification
4107
4108 jlong os::Bsd::fast_thread_cpu_time(clockid_t clockid) {
4109 struct timespec tp;
4110 int rc = os::Bsd::clock_gettime(clockid, &tp);
4111 assert(rc == 0, "clock_gettime is expected to return 0 code");
4112
4113 return (tp.tv_sec * SEC_IN_NANOSECS) + tp.tv_nsec;
4114 }
4115 #endif
4116
4117 /////
4118 // glibc on Bsd platform uses non-documented flag
4119 // to indicate, that some special sort of signal
4120 // trampoline is used.
4121 // We will never set this flag, and we should
4122 // ignore this flag in our diagnostic
4123 #ifdef SIGNIFICANT_SIGNAL_MASK
4124 #undef SIGNIFICANT_SIGNAL_MASK
4125 #endif
4126 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
4127
4128 static const char* get_signal_handler_name(address handler,
4129 char* buf, int buflen) {
4130 int offset;
4131 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
4132 if (found) {
4133 // skip directory names
4134 const char *p1, *p2;
4135 p1 = buf;
4136 size_t len = strlen(os::file_separator());
4137 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
4138 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
4139 } else {
4140 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
4141 }
4142 return buf;
4143 }
4144
4145 static void print_signal_handler(outputStream* st, int sig,
4146 char* buf, size_t buflen) {
4147 struct sigaction sa;
4148
4149 sigaction(sig, NULL, &sa);
4150
4151 // See comment for SIGNIFICANT_SIGNAL_MASK define
4152 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
4153
4154 st->print("%s: ", os::exception_name(sig, buf, buflen));
4155
4156 address handler = (sa.sa_flags & SA_SIGINFO)
4157 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
4158 : CAST_FROM_FN_PTR(address, sa.sa_handler);
4159
4160 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
4161 st->print("SIG_DFL");
4162 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
4163 st->print("SIG_IGN");
4164 } else {
4165 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
4166 }
4167
4168 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
4169
4170 address rh = VMError::get_resetted_sighandler(sig);
4171 // May be, handler was resetted by VMError?
4172 if(rh != NULL) {
4173 handler = rh;
4174 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
4175 }
4176
4177 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
4178
4179 // Check: is it our handler?
4180 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
4181 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
4182 // It is our signal handler
4183 // check for flags, reset system-used one!
4184 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
4185 st->print(
4186 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
4187 os::Bsd::get_our_sigflags(sig));
4188 }
4189 }
4190 st->cr();
4191 }
4192
4193
4194 #define DO_SIGNAL_CHECK(sig) \
4195 if (!sigismember(&check_signal_done, sig)) \
4196 os::Bsd::check_signal_handler(sig)
4197
4198 // This method is a periodic task to check for misbehaving JNI applications
4199 // under CheckJNI, we can add any periodic checks here
4200
4201 void os::run_periodic_checks() {
4202
4203 if (check_signals == false) return;
4204
4205 // SEGV and BUS if overridden could potentially prevent
4206 // generation of hs*.log in the event of a crash, debugging
4207 // such a case can be very challenging, so we absolutely
4208 // check the following for a good measure:
4209 DO_SIGNAL_CHECK(SIGSEGV);
4210 DO_SIGNAL_CHECK(SIGILL);
4211 DO_SIGNAL_CHECK(SIGFPE);
4212 DO_SIGNAL_CHECK(SIGBUS);
4213 DO_SIGNAL_CHECK(SIGPIPE);
4214 DO_SIGNAL_CHECK(SIGXFSZ);
4215
4216
4217 // ReduceSignalUsage allows the user to override these handlers
4218 // see comments at the very top and jvm_solaris.h
4219 if (!ReduceSignalUsage) {
4220 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
4221 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
4222 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
4223 DO_SIGNAL_CHECK(BREAK_SIGNAL);
4224 }
4225
4226 DO_SIGNAL_CHECK(SR_signum);
4227 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
4228 }
4229
4230 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
4231
4232 static os_sigaction_t os_sigaction = NULL;
4233
4234 void os::Bsd::check_signal_handler(int sig) {
4235 char buf[O_BUFLEN];
4236 address jvmHandler = NULL;
4237
4238
4239 struct sigaction act;
4240 if (os_sigaction == NULL) {
4241 // only trust the default sigaction, in case it has been interposed
4242 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
4243 if (os_sigaction == NULL) return;
4244 }
4245
4246 os_sigaction(sig, (struct sigaction*)NULL, &act);
4247
4248
4249 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
4250
4251 address thisHandler = (act.sa_flags & SA_SIGINFO)
4252 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
4253 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
4254
4255
4256 switch(sig) {
4257 case SIGSEGV:
4258 case SIGBUS:
4259 case SIGFPE:
4260 case SIGPIPE:
4261 case SIGILL:
4262 case SIGXFSZ:
4263 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
4264 break;
4265
4266 case SHUTDOWN1_SIGNAL:
4267 case SHUTDOWN2_SIGNAL:
4268 case SHUTDOWN3_SIGNAL:
4269 case BREAK_SIGNAL:
4270 jvmHandler = (address)user_handler();
4271 break;
4272
4273 case INTERRUPT_SIGNAL:
4274 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
4275 break;
4276
4277 default:
4278 if (sig == SR_signum) {
4279 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
4280 } else {
4281 return;
4282 }
4283 break;
4284 }
4285
4286 if (thisHandler != jvmHandler) {
4287 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
4288 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
4289 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
4290 // No need to check this sig any longer
4291 sigaddset(&check_signal_done, sig);
4292 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
4293 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
4294 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
4295 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
4296 // No need to check this sig any longer
4297 sigaddset(&check_signal_done, sig);
4298 }
4299
4300 // Dump all the signal
4301 if (sigismember(&check_signal_done, sig)) {
4302 print_signal_handlers(tty, buf, O_BUFLEN);
4303 }
4304 }
4305
4306 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
4307
4308 extern bool signal_name(int signo, char* buf, size_t len);
4309
4310 const char* os::exception_name(int exception_code, char* buf, size_t size) {
4311 if (0 < exception_code && exception_code <= SIGRTMAX) {
4312 // signal
4313 if (!signal_name(exception_code, buf, size)) {
4314 jio_snprintf(buf, size, "SIG%d", exception_code);
4315 }
4316 return buf;
4317 } else {
4318 return NULL;
4319 }
4320 }
4321
4322 // this is called _before_ the most of global arguments have been parsed
4323 void os::init(void) {
4324 char dummy; /* used to get a guess on initial stack address */
4325 // first_hrtime = gethrtime();
4326
4327 // With BsdThreads the JavaMain thread pid (primordial thread)
4328 // is different than the pid of the java launcher thread.
4329 // So, on Bsd, the launcher thread pid is passed to the VM
4330 // via the sun.java.launcher.pid property.
4331 // Use this property instead of getpid() if it was correctly passed.
4332 // See bug 6351349.
4333 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
4334
4335 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
4336
4337 clock_tics_per_sec = CLK_TCK;
4338
4339 init_random(1234567);
4340
4341 ThreadCritical::initialize();
4342
4343 Bsd::set_page_size(getpagesize());
4344 if (Bsd::page_size() == -1) {
4345 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
4346 strerror(errno)));
4347 }
4348 init_page_sizes((size_t) Bsd::page_size());
4349
4350 Bsd::initialize_system_info();
4351
4352 // main_thread points to the aboriginal thread
4353 Bsd::_main_thread = pthread_self();
4354
4355 Bsd::clock_init();
4356 initial_time_count = os::elapsed_counter();
4357
4358 #ifdef __APPLE__
4359 // XXXDARWIN
4360 // Work around the unaligned VM callbacks in hotspot's
4361 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
4362 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
4363 // alignment when doing symbol lookup. To work around this, we force early
4364 // binding of all symbols now, thus binding when alignment is known-good.
4365 _dyld_bind_fully_image_containing_address((const void *) &os::init);
4366 #endif
4367 }
4368
4369 // To install functions for atexit system call
4370 extern "C" {
4371 static void perfMemory_exit_helper() {
4372 perfMemory_exit();
4373 }
4374 }
4375
4376 // this is called _after_ the global arguments have been parsed
4377 jint os::init_2(void)
4378 {
4379 #ifndef _ALLBSD_SOURCE
4380 Bsd::fast_thread_clock_init();
4381 #endif
4382
4383 // Allocate a single page and mark it as readable for safepoint polling
4384 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
4385 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
4386
4387 os::set_polling_page( polling_page );
4388
4389 #ifndef PRODUCT
4390 if(Verbose && PrintMiscellaneous)
4391 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
4392 #endif
4393
4394 if (!UseMembar) {
4395 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
4396 guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
4397 os::set_memory_serialize_page( mem_serialize_page );
4398
4399 #ifndef PRODUCT
4400 if(Verbose && PrintMiscellaneous)
4401 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
4402 #endif
4403 }
4404
4405 os::large_page_init();
4406
4407 // initialize suspend/resume support - must do this before signal_sets_init()
4408 if (SR_initialize() != 0) {
4409 perror("SR_initialize failed");
4410 return JNI_ERR;
4411 }
4412
4413 Bsd::signal_sets_init();
4414 Bsd::install_signal_handlers();
4415
4416 // Check minimum allowable stack size for thread creation and to initialize
4417 // the java system classes, including StackOverflowError - depends on page
4418 // size. Add a page for compiler2 recursion in main thread.
4419 // Add in 2*BytesPerWord times page size to account for VM stack during
4420 // class initialization depending on 32 or 64 bit VM.
4421 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
4422 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
4423 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
4424
4425 size_t threadStackSizeInBytes = ThreadStackSize * K;
4426 if (threadStackSizeInBytes != 0 &&
4427 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
4428 tty->print_cr("\nThe stack size specified is too small, "
4429 "Specify at least %dk",
4430 os::Bsd::min_stack_allowed/ K);
4431 return JNI_ERR;
4432 }
4433
4434 // Make the stack size a multiple of the page size so that
4435 // the yellow/red zones can be guarded.
4436 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
4437 vm_page_size()));
4438
4439 #ifndef _ALLBSD_SOURCE
4440 Bsd::capture_initial_stack(JavaThread::stack_size_at_create());
4441
4442 Bsd::libpthread_init();
4443 if (PrintMiscellaneous && (Verbose || WizardMode)) {
4444 tty->print_cr("[HotSpot is running with %s, %s(%s)]\n",
4445 Bsd::glibc_version(), Bsd::libpthread_version(),
4446 Bsd::is_floating_stack() ? "floating stack" : "fixed stack");
4447 }
4448
4449 if (UseNUMA) {
4450 if (!Bsd::libnuma_init()) {
4451 UseNUMA = false;
4452 } else {
4453 if ((Bsd::numa_max_node() < 1)) {
4454 // There's only one node(they start from 0), disable NUMA.
4455 UseNUMA = false;
4456 }
4457 }
4458 // With SHM large pages we cannot uncommit a page, so there's not way
4459 // we can make the adaptive lgrp chunk resizing work. If the user specified
4460 // both UseNUMA and UseLargePages (or UseSHM) on the command line - warn and
4461 // disable adaptive resizing.
4462 if (UseNUMA && UseLargePages && UseSHM) {
4463 if (!FLAG_IS_DEFAULT(UseNUMA)) {
4464 if (FLAG_IS_DEFAULT(UseLargePages) && FLAG_IS_DEFAULT(UseSHM)) {
4465 UseLargePages = false;
4466 } else {
4467 warning("UseNUMA is not fully compatible with SHM large pages, disabling adaptive resizing");
4468 UseAdaptiveSizePolicy = false;
4469 UseAdaptiveNUMAChunkSizing = false;
4470 }
4471 } else {
4472 UseNUMA = false;
4473 }
4474 }
4475 if (!UseNUMA && ForceNUMA) {
4476 UseNUMA = true;
4477 }
4478 }
4479 #endif
4480
4481 if (MaxFDLimit) {
4482 // set the number of file descriptors to max. print out error
4483 // if getrlimit/setrlimit fails but continue regardless.
4484 struct rlimit nbr_files;
4485 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
4486 if (status != 0) {
4487 if (PrintMiscellaneous && (Verbose || WizardMode))
4488 perror("os::init_2 getrlimit failed");
4489 } else {
4490 nbr_files.rlim_cur = nbr_files.rlim_max;
4491
4492 #ifdef __APPLE__
4493 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
4494 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
4495 // be used instead
4496 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
4497 #endif
4498
4499 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
4500 if (status != 0) {
4501 if (PrintMiscellaneous && (Verbose || WizardMode))
4502 perror("os::init_2 setrlimit failed");
4503 }
4504 }
4505 }
4506
4507 #ifndef _ALLBSD_SOURCE
4508 // Initialize lock used to serialize thread creation (see os::create_thread)
4509 Bsd::set_createThread_lock(new Mutex(Mutex::leaf, "createThread_lock", false));
4510 #endif
4511
4512 // at-exit methods are called in the reverse order of their registration.
4513 // atexit functions are called on return from main or as a result of a
4514 // call to exit(3C). There can be only 32 of these functions registered
4515 // and atexit() does not set errno.
4516
4517 if (PerfAllowAtExitRegistration) {
4518 // only register atexit functions if PerfAllowAtExitRegistration is set.
4519 // atexit functions can be delayed until process exit time, which
4520 // can be problematic for embedded VM situations. Embedded VMs should
4521 // call DestroyJavaVM() to assure that VM resources are released.
4522
4523 // note: perfMemory_exit_helper atexit function may be removed in
4524 // the future if the appropriate cleanup code can be added to the
4525 // VM_Exit VMOperation's doit method.
4526 if (atexit(perfMemory_exit_helper) != 0) {
4527 warning("os::init2 atexit(perfMemory_exit_helper) failed");
4528 }
4529 }
4530
4531 // initialize thread priority policy
4532 prio_init();
4533
4534 return JNI_OK;
4535 }
4536
4537 // this is called at the end of vm_initialization
4538 void os::init_3(void) { }
4539
4540 // Mark the polling page as unreadable
4541 void os::make_polling_page_unreadable(void) {
4542 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
4543 fatal("Could not disable polling page");
4544 };
4545
4546 // Mark the polling page as readable
4547 void os::make_polling_page_readable(void) {
4548 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
4549 fatal("Could not enable polling page");
4550 }
4551 };
4552
4553 int os::active_processor_count() {
4554 #ifdef _ALLBSD_SOURCE
4555 return _processor_count;
4556 #else
4557 // Bsd doesn't yet have a (official) notion of processor sets,
4558 // so just return the number of online processors.
4559 int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN);
4560 assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check");
4561 return online_cpus;
4562 #endif
4563 }
4564
4565 bool os::distribute_processes(uint length, uint* distribution) {
4566 // Not yet implemented.
4567 return false;
4568 }
4569
4570 bool os::bind_to_processor(uint processor_id) {
4571 // Not yet implemented.
4572 return false;
4573 }
4574
4575 ///
4576
4577 // Suspends the target using the signal mechanism and then grabs the PC before
4578 // resuming the target. Used by the flat-profiler only
4579 ExtendedPC os::get_thread_pc(Thread* thread) {
4580 // Make sure that it is called by the watcher for the VMThread
4581 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
4582 assert(thread->is_VM_thread(), "Can only be called for VMThread");
4583
4584 ExtendedPC epc;
4585
4586 OSThread* osthread = thread->osthread();
4587 if (do_suspend(osthread)) {
4588 if (osthread->ucontext() != NULL) {
4589 epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
4590 } else {
4591 // NULL context is unexpected, double-check this is the VMThread
4592 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
4593 }
4594 do_resume(osthread);
4595 }
4596 // failure means pthread_kill failed for some reason - arguably this is
4597 // a fatal problem, but such problems are ignored elsewhere
4598
4599 return epc;
4600 }
4601
4602 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
4603 {
4604 #ifdef _ALLBSD_SOURCE
4605 return pthread_cond_timedwait(_cond, _mutex, _abstime);
4606 #else
4607 if (is_NPTL()) {
4608 return pthread_cond_timedwait(_cond, _mutex, _abstime);
4609 } else {
4610 #ifndef IA64
4611 // 6292965: BsdThreads pthread_cond_timedwait() resets FPU control
4612 // word back to default 64bit precision if condvar is signaled. Java
4613 // wants 53bit precision. Save and restore current value.
4614 int fpu = get_fpu_control_word();
4615 #endif // IA64
4616 int status = pthread_cond_timedwait(_cond, _mutex, _abstime);
4617 #ifndef IA64
4618 set_fpu_control_word(fpu);
4619 #endif // IA64
4620 return status;
4621 }
4622 #endif
4623 }
4624
4625 ////////////////////////////////////////////////////////////////////////////////
4626 // debug support
4627
4628 static address same_page(address x, address y) {
4629 int page_bits = -os::vm_page_size();
4630 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
4631 return x;
4632 else if (x > y)
4633 return (address)(intptr_t(y) | ~page_bits) + 1;
4634 else
4635 return (address)(intptr_t(y) & page_bits);
4636 }
4637
4638 bool os::find(address addr, outputStream* st) {
4639 Dl_info dlinfo;
4640 memset(&dlinfo, 0, sizeof(dlinfo));
4641 if (dladdr(addr, &dlinfo)) {
4642 st->print(PTR_FORMAT ": ", addr);
4643 if (dlinfo.dli_sname != NULL) {
4644 st->print("%s+%#x", dlinfo.dli_sname,
4645 addr - (intptr_t)dlinfo.dli_saddr);
4646 } else if (dlinfo.dli_fname) {
4647 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
4648 } else {
4649 st->print("<absolute address>");
4650 }
4651 if (dlinfo.dli_fname) {
4652 st->print(" in %s", dlinfo.dli_fname);
4653 }
4654 if (dlinfo.dli_fbase) {
4655 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
4656 }
4657 st->cr();
4658
4659 if (Verbose) {
4660 // decode some bytes around the PC
4661 address begin = same_page(addr-40, addr);
4662 address end = same_page(addr+40, addr);
4663 address lowest = (address) dlinfo.dli_sname;
4664 if (!lowest) lowest = (address) dlinfo.dli_fbase;
4665 if (begin < lowest) begin = lowest;
4666 Dl_info dlinfo2;
4667 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
4668 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
4669 end = (address) dlinfo2.dli_saddr;
4670 Disassembler::decode(begin, end, st);
4671 }
4672 return true;
4673 }
4674 return false;
4675 }
4676
4677 ////////////////////////////////////////////////////////////////////////////////
4678 // misc
4679
4680 // This does not do anything on Bsd. This is basically a hook for being
4681 // able to use structured exception handling (thread-local exception filters)
4682 // on, e.g., Win32.
4683 void
4684 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
4685 JavaCallArguments* args, Thread* thread) {
4686 f(value, method, args, thread);
4687 }
4688
4689 void os::print_statistics() {
4690 }
4691
4692 int os::message_box(const char* title, const char* message) {
4693 int i;
4694 fdStream err(defaultStream::error_fd());
4695 for (i = 0; i < 78; i++) err.print_raw("=");
4696 err.cr();
4697 err.print_raw_cr(title);
4698 for (i = 0; i < 78; i++) err.print_raw("-");
4699 err.cr();
4700 err.print_raw_cr(message);
4701 for (i = 0; i < 78; i++) err.print_raw("=");
4702 err.cr();
4703
4704 char buf[16];
4705 // Prevent process from exiting upon "read error" without consuming all CPU
4706 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
4707
4708 return buf[0] == 'y' || buf[0] == 'Y';
4709 }
4710
4711 int os::stat(const char *path, struct stat *sbuf) {
4712 char pathbuf[MAX_PATH];
4713 if (strlen(path) > MAX_PATH - 1) {
4714 errno = ENAMETOOLONG;
4715 return -1;
4716 }
4717 os::native_path(strcpy(pathbuf, path));
4718 return ::stat(pathbuf, sbuf);
4719 }
4720
4721 bool os::check_heap(bool force) {
4722 return true;
4723 }
4724
4725 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
4726 return ::vsnprintf(buf, count, format, args);
4727 }
4728
4729 // Is a (classpath) directory empty?
4730 bool os::dir_is_empty(const char* path) {
4731 DIR *dir = NULL;
4732 struct dirent *ptr;
4733
4734 dir = opendir(path);
4735 if (dir == NULL) return true;
4736
4737 /* Scan the directory */
4738 bool result = true;
4739 char buf[sizeof(struct dirent) + MAX_PATH];
4740 while (result && (ptr = ::readdir(dir)) != NULL) {
4741 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
4742 result = false;
4743 }
4744 }
4745 closedir(dir);
4746 return result;
4747 }
4748
4749 // This code originates from JDK's sysOpen and open64_w
4750 // from src/solaris/hpi/src/system_md.c
4751
4752 #ifndef O_DELETE
4753 #define O_DELETE 0x10000
4754 #endif
4755
4756 // Open a file. Unlink the file immediately after open returns
4757 // if the specified oflag has the O_DELETE flag set.
4758 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
4759
4760 int os::open(const char *path, int oflag, int mode) {
4761
4762 if (strlen(path) > MAX_PATH - 1) {
4763 errno = ENAMETOOLONG;
4764 return -1;
4765 }
4766 int fd;
4767 int o_delete = (oflag & O_DELETE);
4768 oflag = oflag & ~O_DELETE;
4769
4770 fd = ::open(path, oflag, mode);
4771 if (fd == -1) return -1;
4772
4773 //If the open succeeded, the file might still be a directory
4774 {
4775 struct stat buf;
4776 int ret = ::fstat(fd, &buf);
4777 int st_mode = buf.st_mode;
4778
4779 if (ret != -1) {
4780 if ((st_mode & S_IFMT) == S_IFDIR) {
4781 errno = EISDIR;
4782 ::close(fd);
4783 return -1;
4784 }
4785 } else {
4786 ::close(fd);
4787 return -1;
4788 }
4789 }
4790
4791 /*
4792 * All file descriptors that are opened in the JVM and not
4793 * specifically destined for a subprocess should have the
4794 * close-on-exec flag set. If we don't set it, then careless 3rd
4795 * party native code might fork and exec without closing all
4796 * appropriate file descriptors (e.g. as we do in closeDescriptors in
4797 * UNIXProcess.c), and this in turn might:
4798 *
4799 * - cause end-of-file to fail to be detected on some file
4800 * descriptors, resulting in mysterious hangs, or
4801 *
4802 * - might cause an fopen in the subprocess to fail on a system
4803 * suffering from bug 1085341.
4804 *
4805 * (Yes, the default setting of the close-on-exec flag is a Unix
4806 * design flaw)
4807 *
4808 * See:
4809 * 1085341: 32-bit stdio routines should support file descriptors >255
4810 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4811 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4812 */
4813 #ifdef FD_CLOEXEC
4814 {
4815 int flags = ::fcntl(fd, F_GETFD);
4816 if (flags != -1)
4817 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4818 }
4819 #endif
4820
4821 if (o_delete != 0) {
4822 ::unlink(path);
4823 }
4824 return fd;
4825 }
4826
4827
4828 // create binary file, rewriting existing file if required
4829 int os::create_binary_file(const char* path, bool rewrite_existing) {
4830 int oflags = O_WRONLY | O_CREAT;
4831 if (!rewrite_existing) {
4832 oflags |= O_EXCL;
4833 }
4834 return ::open(path, oflags, S_IREAD | S_IWRITE);
4835 }
4836
4837 // return current position of file pointer
4838 jlong os::current_file_offset(int fd) {
4839 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4840 }
4841
4842 // move file pointer to the specified offset
4843 jlong os::seek_to_file_offset(int fd, jlong offset) {
4844 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4845 }
4846
4847 // This code originates from JDK's sysAvailable
4848 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4849
4850 int os::available(int fd, jlong *bytes) {
4851 jlong cur, end;
4852 int mode;
4853 struct stat buf;
4854
4855 if (::fstat(fd, &buf) >= 0) {
4856 mode = buf.st_mode;
4857 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4858 /*
4859 * XXX: is the following call interruptible? If so, this might
4860 * need to go through the INTERRUPT_IO() wrapper as for other
4861 * blocking, interruptible calls in this file.
4862 */
4863 int n;
4864 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4865 *bytes = n;
4866 return 1;
4867 }
4868 }
4869 }
4870 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4871 return 0;
4872 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4873 return 0;
4874 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4875 return 0;
4876 }
4877 *bytes = end - cur;
4878 return 1;
4879 }
4880
4881 int os::socket_available(int fd, jint *pbytes) {
4882 if (fd < 0)
4883 return OS_OK;
4884
4885 int ret;
4886
4887 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4888
4889 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4890 // is expected to return 0 on failure and 1 on success to the jdk.
4891
4892 return (ret == OS_ERR) ? 0 : 1;
4893 }
4894
4895 // Map a block of memory.
4896 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
4897 char *addr, size_t bytes, bool read_only,
4898 bool allow_exec) {
4899 int prot;
4900 int flags;
4901
4902 if (read_only) {
4903 prot = PROT_READ;
4904 flags = MAP_SHARED;
4905 } else {
4906 prot = PROT_READ | PROT_WRITE;
4907 flags = MAP_PRIVATE;
4908 }
4909
4910 if (allow_exec) {
4911 prot |= PROT_EXEC;
4912 }
4913
4914 if (addr != NULL) {
4915 flags |= MAP_FIXED;
4916 }
4917
4918 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4919 fd, file_offset);
4920 if (mapped_address == MAP_FAILED) {
4921 return NULL;
4922 }
4923 return mapped_address;
4924 }
4925
4926
4927 // Remap a block of memory.
4928 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
4929 char *addr, size_t bytes, bool read_only,
4930 bool allow_exec) {
4931 // same as map_memory() on this OS
4932 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4933 allow_exec);
4934 }
4935
4936
4937 // Unmap a block of memory.
4938 bool os::unmap_memory(char* addr, size_t bytes) {
4939 return munmap(addr, bytes) == 0;
4940 }
4941
4942 #ifndef _ALLBSD_SOURCE
4943 static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time);
4944
4945 static clockid_t thread_cpu_clockid(Thread* thread) {
4946 pthread_t tid = thread->osthread()->pthread_id();
4947 clockid_t clockid;
4948
4949 // Get thread clockid
4950 int rc = os::Bsd::pthread_getcpuclockid(tid, &clockid);
4951 assert(rc == 0, "pthread_getcpuclockid is expected to return 0 code");
4952 return clockid;
4953 }
4954 #endif
4955
4956 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4957 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4958 // of a thread.
4959 //
4960 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4961 // the fast estimate available on the platform.
4962
4963 jlong os::current_thread_cpu_time() {
4964 #ifdef __APPLE__
4965 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4966 #elif !defined(_ALLBSD_SOURCE)
4967 if (os::Bsd::supports_fast_thread_cpu_time()) {
4968 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID);
4969 } else {
4970 // return user + sys since the cost is the same
4971 return slow_thread_cpu_time(Thread::current(), true /* user + sys */);
4972 }
4973 #endif
4974 }
4975
4976 jlong os::thread_cpu_time(Thread* thread) {
4977 #ifndef _ALLBSD_SOURCE
4978 // consistent with what current_thread_cpu_time() returns
4979 if (os::Bsd::supports_fast_thread_cpu_time()) {
4980 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread));
4981 } else {
4982 return slow_thread_cpu_time(thread, true /* user + sys */);
4983 }
4984 #endif
4985 }
4986
4987 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4988 #ifdef __APPLE__
4989 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4990 #elif !defined(_ALLBSD_SOURCE)
4991 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) {
4992 return os::Bsd::fast_thread_cpu_time(CLOCK_THREAD_CPUTIME_ID);
4993 } else {
4994 return slow_thread_cpu_time(Thread::current(), user_sys_cpu_time);
4995 }
4996 #endif
4997 }
4998
4999 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
5000 #ifdef __APPLE__
5001 struct thread_basic_info tinfo;
5002 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
5003 kern_return_t kr;
5004 mach_port_t mach_thread;
5005
5006 mach_thread = pthread_mach_thread_np(thread->osthread()->thread_id());
5007 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
5008 if (kr != KERN_SUCCESS)
5009 return -1;
5010
5011 if (user_sys_cpu_time) {
5012 jlong nanos;
5013 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
5014 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
5015 return nanos;
5016 } else {
5017 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
5018 }
5019 #elif !defined(_ALLBSD_SOURCE)
5020 if (user_sys_cpu_time && os::Bsd::supports_fast_thread_cpu_time()) {
5021 return os::Bsd::fast_thread_cpu_time(thread_cpu_clockid(thread));
5022 } else {
5023 return slow_thread_cpu_time(thread, user_sys_cpu_time);
5024 }
5025 #endif
5026 }
5027
5028 #ifndef _ALLBSD_SOURCE
5029 //
5030 // -1 on error.
5031 //
5032
5033 static jlong slow_thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
5034 static bool proc_pid_cpu_avail = true;
5035 static bool proc_task_unchecked = true;
5036 static const char *proc_stat_path = "/proc/%d/stat";
5037 pid_t tid = thread->osthread()->thread_id();
5038 int i;
5039 char *s;
5040 char stat[2048];
5041 int statlen;
5042 char proc_name[64];
5043 int count;
5044 long sys_time, user_time;
5045 char string[64];
5046 char cdummy;
5047 int idummy;
5048 long ldummy;
5049 FILE *fp;
5050
5051 // We first try accessing /proc/<pid>/cpu since this is faster to
5052 // process. If this file is not present (bsd kernels 2.5 and above)
5053 // then we open /proc/<pid>/stat.
5054 if ( proc_pid_cpu_avail ) {
5055 sprintf(proc_name, "/proc/%d/cpu", tid);
5056 fp = fopen(proc_name, "r");
5057 if ( fp != NULL ) {
5058 count = fscanf( fp, "%s %lu %lu\n", string, &user_time, &sys_time);
5059 fclose(fp);
5060 if ( count != 3 ) return -1;
5061
5062 if (user_sys_cpu_time) {
5063 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec);
5064 } else {
5065 return (jlong)user_time * (1000000000 / clock_tics_per_sec);
5066 }
5067 }
5068 else proc_pid_cpu_avail = false;
5069 }
5070
5071 // The /proc/<tid>/stat aggregates per-process usage on
5072 // new Bsd kernels 2.6+ where NPTL is supported.
5073 // The /proc/self/task/<tid>/stat still has the per-thread usage.
5074 // See bug 6328462.
5075 // There can be no directory /proc/self/task on kernels 2.4 with NPTL
5076 // and possibly in some other cases, so we check its availability.
5077 if (proc_task_unchecked && os::Bsd::is_NPTL()) {
5078 // This is executed only once
5079 proc_task_unchecked = false;
5080 fp = fopen("/proc/self/task", "r");
5081 if (fp != NULL) {
5082 proc_stat_path = "/proc/self/task/%d/stat";
5083 fclose(fp);
5084 }
5085 }
5086
5087 sprintf(proc_name, proc_stat_path, tid);
5088 fp = fopen(proc_name, "r");
5089 if ( fp == NULL ) return -1;
5090 statlen = fread(stat, 1, 2047, fp);
5091 stat[statlen] = '\0';
5092 fclose(fp);
5093
5094 // Skip pid and the command string. Note that we could be dealing with
5095 // weird command names, e.g. user could decide to rename java launcher
5096 // to "java 1.4.2 :)", then the stat file would look like
5097 // 1234 (java 1.4.2 :)) R ... ...
5098 // We don't really need to know the command string, just find the last
5099 // occurrence of ")" and then start parsing from there. See bug 4726580.
5100 s = strrchr(stat, ')');
5101 i = 0;
5102 if (s == NULL ) return -1;
5103
5104 // Skip blank chars
5105 do s++; while (isspace(*s));
5106
5107 count = sscanf(s,"%c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu",
5108 &cdummy, &idummy, &idummy, &idummy, &idummy, &idummy,
5109 &ldummy, &ldummy, &ldummy, &ldummy, &ldummy,
5110 &user_time, &sys_time);
5111 if ( count != 13 ) return -1;
5112 if (user_sys_cpu_time) {
5113 return ((jlong)sys_time + (jlong)user_time) * (1000000000 / clock_tics_per_sec);
5114 } else {
5115 return (jlong)user_time * (1000000000 / clock_tics_per_sec);
5116 }
5117 }
5118 #endif
5119
5120 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
5121 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
5122 info_ptr->may_skip_backward = false; // elapsed time not wall time
5123 info_ptr->may_skip_forward = false; // elapsed time not wall time
5124 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
5125 }
5126
5127 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
5128 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
5129 info_ptr->may_skip_backward = false; // elapsed time not wall time
5130 info_ptr->may_skip_forward = false; // elapsed time not wall time
5131 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
5132 }
5133
5134 bool os::is_thread_cpu_time_supported() {
5135 #ifdef __APPLE__
5136 return true;
5137 #elif defined(_ALLBSD_SOURCE)
5138 return false;
5139 #else
5140 return true;
5141 #endif
5142 }
5143
5144 // System loadavg support. Returns -1 if load average cannot be obtained.
5145 // Bsd doesn't yet have a (official) notion of processor sets,
5146 // so just return the system wide load average.
5147 int os::loadavg(double loadavg[], int nelem) {
5148 return ::getloadavg(loadavg, nelem);
5149 }
5150
5151 void os::pause() {
5152 char filename[MAX_PATH];
5153 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
5154 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
5155 } else {
5156 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
5157 }
5158
5159 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
5160 if (fd != -1) {
5161 struct stat buf;
5162 ::close(fd);
5163 while (::stat(filename, &buf) == 0) {
5164 (void)::poll(NULL, 0, 100);
5165 }
5166 } else {
5167 jio_fprintf(stderr,
5168 "Could not open pause file '%s', continuing immediately.\n", filename);
5169 }
5170 }
5171
5172
5173 // Refer to the comments in os_solaris.cpp park-unpark.
5174 //
5175 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
5176 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
5177 // For specifics regarding the bug see GLIBC BUGID 261237 :
5178 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
5179 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
5180 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
5181 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
5182 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
5183 // and monitorenter when we're using 1-0 locking. All those operations may result in
5184 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
5185 // of libpthread avoids the problem, but isn't practical.
5186 //
5187 // Possible remedies:
5188 //
5189 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
5190 // This is palliative and probabilistic, however. If the thread is preempted
5191 // between the call to compute_abstime() and pthread_cond_timedwait(), more
5192 // than the minimum period may have passed, and the abstime may be stale (in the
5193 // past) resultin in a hang. Using this technique reduces the odds of a hang
5194 // but the JVM is still vulnerable, particularly on heavily loaded systems.
5195 //
5196 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
5197 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
5198 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
5199 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
5200 // thread.
5201 //
5202 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
5203 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
5204 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
5205 // This also works well. In fact it avoids kernel-level scalability impediments
5206 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
5207 // timers in a graceful fashion.
5208 //
5209 // 4. When the abstime value is in the past it appears that control returns
5210 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
5211 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
5212 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
5213 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
5214 // It may be possible to avoid reinitialization by checking the return
5215 // value from pthread_cond_timedwait(). In addition to reinitializing the
5216 // condvar we must establish the invariant that cond_signal() is only called
5217 // within critical sections protected by the adjunct mutex. This prevents
5218 // cond_signal() from "seeing" a condvar that's in the midst of being
5219 // reinitialized or that is corrupt. Sadly, this invariant obviates the
5220 // desirable signal-after-unlock optimization that avoids futile context switching.
5221 //
5222 // I'm also concerned that some versions of NTPL might allocate an auxilliary
5223 // structure when a condvar is used or initialized. cond_destroy() would
5224 // release the helper structure. Our reinitialize-after-timedwait fix
5225 // put excessive stress on malloc/free and locks protecting the c-heap.
5226 //
5227 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
5228 // It may be possible to refine (4) by checking the kernel and NTPL verisons
5229 // and only enabling the work-around for vulnerable environments.
5230
5231 // utility to compute the abstime argument to timedwait:
5232 // millis is the relative timeout time
5233 // abstime will be the absolute timeout time
5234 // TODO: replace compute_abstime() with unpackTime()
5235
5236 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
5237 if (millis < 0) millis = 0;
5238 struct timeval now;
5239 int status = gettimeofday(&now, NULL);
5240 assert(status == 0, "gettimeofday");
5241 jlong seconds = millis / 1000;
5242 millis %= 1000;
5243 if (seconds > 50000000) { // see man cond_timedwait(3T)
5244 seconds = 50000000;
5245 }
5246 abstime->tv_sec = now.tv_sec + seconds;
5247 long usec = now.tv_usec + millis * 1000;
5248 if (usec >= 1000000) {
5249 abstime->tv_sec += 1;
5250 usec -= 1000000;
5251 }
5252 abstime->tv_nsec = usec * 1000;
5253 return abstime;
5254 }
5255
5256
5257 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
5258 // Conceptually TryPark() should be equivalent to park(0).
5259
5260 int os::PlatformEvent::TryPark() {
5261 for (;;) {
5262 const int v = _Event ;
5263 guarantee ((v == 0) || (v == 1), "invariant") ;
5264 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
5265 }
5266 }
5267
5268 void os::PlatformEvent::park() { // AKA "down()"
5269 // Invariant: Only the thread associated with the Event/PlatformEvent
5270 // may call park().
5271 // TODO: assert that _Assoc != NULL or _Assoc == Self
5272 int v ;
5273 for (;;) {
5274 v = _Event ;
5275 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
5276 }
5277 guarantee (v >= 0, "invariant") ;
5278 if (v == 0) {
5279 // Do this the hard way by blocking ...
5280 int status = pthread_mutex_lock(_mutex);
5281 assert_status(status == 0, status, "mutex_lock");
5282 guarantee (_nParked == 0, "invariant") ;
5283 ++ _nParked ;
5284 while (_Event < 0) {
5285 status = pthread_cond_wait(_cond, _mutex);
5286 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
5287 // Treat this the same as if the wait was interrupted
5288 if (status == ETIMEDOUT) { status = EINTR; }
5289 assert_status(status == 0 || status == EINTR, status, "cond_wait");
5290 }
5291 -- _nParked ;
5292
5293 // In theory we could move the ST of 0 into _Event past the unlock(),
5294 // but then we'd need a MEMBAR after the ST.
5295 _Event = 0 ;
5296 status = pthread_mutex_unlock(_mutex);
5297 assert_status(status == 0, status, "mutex_unlock");
5298 }
5299 guarantee (_Event >= 0, "invariant") ;
5300 }
5301
5302 int os::PlatformEvent::park(jlong millis) {
5303 guarantee (_nParked == 0, "invariant") ;
5304
5305 int v ;
5306 for (;;) {
5307 v = _Event ;
5308 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
5309 }
5310 guarantee (v >= 0, "invariant") ;
5311 if (v != 0) return OS_OK ;
5312
5313 // We do this the hard way, by blocking the thread.
5314 // Consider enforcing a minimum timeout value.
5315 struct timespec abst;
5316 compute_abstime(&abst, millis);
5317
5318 int ret = OS_TIMEOUT;
5319 int status = pthread_mutex_lock(_mutex);
5320 assert_status(status == 0, status, "mutex_lock");
5321 guarantee (_nParked == 0, "invariant") ;
5322 ++_nParked ;
5323
5324 // Object.wait(timo) will return because of
5325 // (a) notification
5326 // (b) timeout
5327 // (c) thread.interrupt
5328 //
5329 // Thread.interrupt and object.notify{All} both call Event::set.
5330 // That is, we treat thread.interrupt as a special case of notification.
5331 // The underlying Solaris implementation, cond_timedwait, admits
5332 // spurious/premature wakeups, but the JLS/JVM spec prevents the
5333 // JVM from making those visible to Java code. As such, we must
5334 // filter out spurious wakeups. We assume all ETIME returns are valid.
5335 //
5336 // TODO: properly differentiate simultaneous notify+interrupt.
5337 // In that case, we should propagate the notify to another waiter.
5338
5339 while (_Event < 0) {
5340 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
5341 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
5342 pthread_cond_destroy (_cond);
5343 pthread_cond_init (_cond, NULL) ;
5344 }
5345 assert_status(status == 0 || status == EINTR ||
5346 status == ETIMEDOUT,
5347 status, "cond_timedwait");
5348 if (!FilterSpuriousWakeups) break ; // previous semantics
5349 if (status == ETIMEDOUT) break ;
5350 // We consume and ignore EINTR and spurious wakeups.
5351 }
5352 --_nParked ;
5353 if (_Event >= 0) {
5354 ret = OS_OK;
5355 }
5356 _Event = 0 ;
5357 status = pthread_mutex_unlock(_mutex);
5358 assert_status(status == 0, status, "mutex_unlock");
5359 assert (_nParked == 0, "invariant") ;
5360 return ret;
5361 }
5362
5363 void os::PlatformEvent::unpark() {
5364 int v, AnyWaiters ;
5365 for (;;) {
5366 v = _Event ;
5367 if (v > 0) {
5368 // The LD of _Event could have reordered or be satisfied
5369 // by a read-aside from this processor's write buffer.
5370 // To avoid problems execute a barrier and then
5371 // ratify the value.
5372 OrderAccess::fence() ;
5373 if (_Event == v) return ;
5374 continue ;
5375 }
5376 if (Atomic::cmpxchg (v+1, &_Event, v) == v) break ;
5377 }
5378 if (v < 0) {
5379 // Wait for the thread associated with the event to vacate
5380 int status = pthread_mutex_lock(_mutex);
5381 assert_status(status == 0, status, "mutex_lock");
5382 AnyWaiters = _nParked ;
5383 assert (AnyWaiters == 0 || AnyWaiters == 1, "invariant") ;
5384 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
5385 AnyWaiters = 0 ;
5386 pthread_cond_signal (_cond);
5387 }
5388 status = pthread_mutex_unlock(_mutex);
5389 assert_status(status == 0, status, "mutex_unlock");
5390 if (AnyWaiters != 0) {
5391 status = pthread_cond_signal(_cond);
5392 assert_status(status == 0, status, "cond_signal");
5393 }
5394 }
5395
5396 // Note that we signal() _after dropping the lock for "immortal" Events.
5397 // This is safe and avoids a common class of futile wakeups. In rare
5398 // circumstances this can cause a thread to return prematurely from
5399 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
5400 // simply re-test the condition and re-park itself.
5401 }
5402
5403
5404 // JSR166
5405 // -------------------------------------------------------
5406
5407 /*
5408 * The solaris and bsd implementations of park/unpark are fairly
5409 * conservative for now, but can be improved. They currently use a
5410 * mutex/condvar pair, plus a a count.
5411 * Park decrements count if > 0, else does a condvar wait. Unpark
5412 * sets count to 1 and signals condvar. Only one thread ever waits
5413 * on the condvar. Contention seen when trying to park implies that someone
5414 * is unparking you, so don't wait. And spurious returns are fine, so there
5415 * is no need to track notifications.
5416 */
5417
5418
5419 #define NANOSECS_PER_SEC 1000000000
5420 #define NANOSECS_PER_MILLISEC 1000000
5421 #define MAX_SECS 100000000
5422 /*
5423 * This code is common to bsd and solaris and will be moved to a
5424 * common place in dolphin.
5425 *
5426 * The passed in time value is either a relative time in nanoseconds
5427 * or an absolute time in milliseconds. Either way it has to be unpacked
5428 * into suitable seconds and nanoseconds components and stored in the
5429 * given timespec structure.
5430 * Given time is a 64-bit value and the time_t used in the timespec is only
5431 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
5432 * overflow if times way in the future are given. Further on Solaris versions
5433 * prior to 10 there is a restriction (see cond_timedwait) that the specified
5434 * number of seconds, in abstime, is less than current_time + 100,000,000.
5435 * As it will be 28 years before "now + 100000000" will overflow we can
5436 * ignore overflow and just impose a hard-limit on seconds using the value
5437 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
5438 * years from "now".
5439 */
5440
5441 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
5442 assert (time > 0, "convertTime");
5443
5444 struct timeval now;
5445 int status = gettimeofday(&now, NULL);
5446 assert(status == 0, "gettimeofday");
5447
5448 time_t max_secs = now.tv_sec + MAX_SECS;
5449
5450 if (isAbsolute) {
5451 jlong secs = time / 1000;
5452 if (secs > max_secs) {
5453 absTime->tv_sec = max_secs;
5454 }
5455 else {
5456 absTime->tv_sec = secs;
5457 }
5458 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
5459 }
5460 else {
5461 jlong secs = time / NANOSECS_PER_SEC;
5462 if (secs >= MAX_SECS) {
5463 absTime->tv_sec = max_secs;
5464 absTime->tv_nsec = 0;
5465 }
5466 else {
5467 absTime->tv_sec = now.tv_sec + secs;
5468 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
5469 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
5470 absTime->tv_nsec -= NANOSECS_PER_SEC;
5471 ++absTime->tv_sec; // note: this must be <= max_secs
5472 }
5473 }
5474 }
5475 assert(absTime->tv_sec >= 0, "tv_sec < 0");
5476 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
5477 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
5478 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
5479 }
5480
5481 void Parker::park(bool isAbsolute, jlong time) {
5482 // Optional fast-path check:
5483 // Return immediately if a permit is available.
5484 if (_counter > 0) {
5485 _counter = 0 ;
5486 OrderAccess::fence();
5487 return ;
5488 }
5489
5490 Thread* thread = Thread::current();
5491 assert(thread->is_Java_thread(), "Must be JavaThread");
5492 JavaThread *jt = (JavaThread *)thread;
5493
5494 // Optional optimization -- avoid state transitions if there's an interrupt pending.
5495 // Check interrupt before trying to wait
5496 if (Thread::is_interrupted(thread, false)) {
5497 return;
5498 }
5499
5500 // Next, demultiplex/decode time arguments
5501 struct timespec absTime;
5502 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
5503 return;
5504 }
5505 if (time > 0) {
5506 unpackTime(&absTime, isAbsolute, time);
5507 }
5508
5509
5510 // Enter safepoint region
5511 // Beware of deadlocks such as 6317397.
5512 // The per-thread Parker:: mutex is a classic leaf-lock.
5513 // In particular a thread must never block on the Threads_lock while
5514 // holding the Parker:: mutex. If safepoints are pending both the
5515 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
5516 ThreadBlockInVM tbivm(jt);
5517
5518 // Don't wait if cannot get lock since interference arises from
5519 // unblocking. Also. check interrupt before trying wait
5520 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
5521 return;
5522 }
5523
5524 int status ;
5525 if (_counter > 0) { // no wait needed
5526 _counter = 0;
5527 status = pthread_mutex_unlock(_mutex);
5528 assert (status == 0, "invariant") ;
5529 OrderAccess::fence();
5530 return;
5531 }
5532
5533 #ifdef ASSERT
5534 // Don't catch signals while blocked; let the running threads have the signals.
5535 // (This allows a debugger to break into the running thread.)
5536 sigset_t oldsigs;
5537 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
5538 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
5539 #endif
5540
5541 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
5542 jt->set_suspend_equivalent();
5543 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
5544
5545 if (time == 0) {
5546 status = pthread_cond_wait (_cond, _mutex) ;
5547 } else {
5548 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
5549 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
5550 pthread_cond_destroy (_cond) ;
5551 pthread_cond_init (_cond, NULL);
5552 }
5553 }
5554 assert_status(status == 0 || status == EINTR ||
5555 status == ETIMEDOUT,
5556 status, "cond_timedwait");
5557
5558 #ifdef ASSERT
5559 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
5560 #endif
5561
5562 _counter = 0 ;
5563 status = pthread_mutex_unlock(_mutex) ;
5564 assert_status(status == 0, status, "invariant") ;
5565 // If externally suspended while waiting, re-suspend
5566 if (jt->handle_special_suspend_equivalent_condition()) {
5567 jt->java_suspend_self();
5568 }
5569
5570 OrderAccess::fence();
5571 }
5572
5573 void Parker::unpark() {
5574 int s, status ;
5575 status = pthread_mutex_lock(_mutex);
5576 assert (status == 0, "invariant") ;
5577 s = _counter;
5578 _counter = 1;
5579 if (s < 1) {
5580 if (WorkAroundNPTLTimedWaitHang) {
5581 status = pthread_cond_signal (_cond) ;
5582 assert (status == 0, "invariant") ;
5583 status = pthread_mutex_unlock(_mutex);
5584 assert (status == 0, "invariant") ;
5585 } else {
5586 status = pthread_mutex_unlock(_mutex);
5587 assert (status == 0, "invariant") ;
5588 status = pthread_cond_signal (_cond) ;
5589 assert (status == 0, "invariant") ;
5590 }
5591 } else {
5592 pthread_mutex_unlock(_mutex);
5593 assert (status == 0, "invariant") ;
5594 }
5595 }
5596
5597
5598 /* Darwin has no "environ" in a dynamic library. */
5599 #ifdef __APPLE__
5600 #include <crt_externs.h>
5601 #define environ (*_NSGetEnviron())
5602 #else
5603 extern char** environ;
5604 #endif
5605
5606 // Run the specified command in a separate process. Return its exit value,
5607 // or -1 on failure (e.g. can't fork a new process).
5608 // Unlike system(), this function can be called from signal handler. It
5609 // doesn't block SIGINT et al.
5610 int os::fork_and_exec(char* cmd) {
5611 const char * argv[4] = {"sh", "-c", cmd, NULL};
5612
5613 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
5614 // pthread_atfork handlers and reset pthread library. All we need is a
5615 // separate process to execve. Make a direct syscall to fork process.
5616 // On IA64 there's no fork syscall, we have to use fork() and hope for
5617 // the best...
5618 pid_t pid = fork();
5619
5620 if (pid < 0) {
5621 // fork failed
5622 return -1;
5623
5624 } else if (pid == 0) {
5625 // child process
5626
5627 // execve() in BsdThreads will call pthread_kill_other_threads_np()
5628 // first to kill every thread on the thread list. Because this list is
5629 // not reset by fork() (see notes above), execve() will instead kill
5630 // every thread in the parent process. We know this is the only thread
5631 // in the new process, so make a system call directly.
5632 // IA64 should use normal execve() from glibc to match the glibc fork()
5633 // above.
5634 execve("/bin/sh", (char* const*)argv, environ);
5635
5636 // execve failed
5637 _exit(-1);
5638
5639 } else {
5640 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
5641 // care about the actual exit code, for now.
5642
5643 int status;
5644
5645 // Wait for the child process to exit. This returns immediately if
5646 // the child has already exited. */
5647 while (waitpid(pid, &status, 0) < 0) {
5648 switch (errno) {
5649 case ECHILD: return 0;
5650 case EINTR: break;
5651 default: return -1;
5652 }
5653 }
5654
5655 if (WIFEXITED(status)) {
5656 // The child exited normally; get its exit code.
5657 return WEXITSTATUS(status);
5658 } else if (WIFSIGNALED(status)) {
5659 // The child exited because of a signal
5660 // The best value to return is 0x80 + signal number,
5661 // because that is what all Unix shells do, and because
5662 // it allows callers to distinguish between process exit and
5663 // process death by signal.
5664 return 0x80 + WTERMSIG(status);
5665 } else {
5666 // Unknown exit code; pass it through
5667 return status;
5668 }
5669 }
5670 }
5671
5672 // is_headless_jre()
5673 //
5674 // Test for the existence of libmawt in motif21 or xawt directories
5675 // in order to report if we are running in a headless jre
5676 //
5677 bool os::is_headless_jre() {
5678 struct stat statbuf;
5679 char buf[MAXPATHLEN];
5680 char libmawtpath[MAXPATHLEN];
5681 const char *xawtstr = "/xawt/libmawt.so";
5682 const char *motifstr = "/motif21/libmawt.so";
5683 char *p;
5684
5685 // Get path to libjvm.so
5686 os::jvm_path(buf, sizeof(buf));
5687
5688 // Get rid of libjvm.so
5689 p = strrchr(buf, '/');
5690 if (p == NULL) return false;
5691 else *p = '\0';
5692
5693 // Get rid of client or server
5694 p = strrchr(buf, '/');
5695 if (p == NULL) return false;
5696 else *p = '\0';
5697
5698 // check xawt/libmawt.so
5699 strcpy(libmawtpath, buf);
5700 strcat(libmawtpath, xawtstr);
5701 if (::stat(libmawtpath, &statbuf) == 0) return false;
5702
5703 // check motif21/libmawt.so
5704 strcpy(libmawtpath, buf);
5705 strcat(libmawtpath, motifstr);
5706 if (::stat(libmawtpath, &statbuf) == 0) return false;
5707
5708 return true;
5709 }