1 /*
2 * Copyright (c) 1999, 2013, 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 "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
67
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
103 # include <sys/syscall.h>
104
105 #if defined(__FreeBSD__) || defined(__NetBSD__)
106 # include <elf.h>
107 #endif
108
109 #ifdef __APPLE__
110 # include <mach/mach.h> // semaphore_* API
111 # include <mach-o/dyld.h>
112 # include <sys/proc_info.h>
113 # include <objc/objc-auto.h>
114 #endif
115
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
118 #endif
119
120 #define MAX_PATH (2 * K)
121
122 // for timer info max values which include all bits
123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
124
125 #define LARGEPAGES_BIT (1 << 6)
126 ////////////////////////////////////////////////////////////////////////////////
127 // global variables
128 julong os::Bsd::_physical_memory = 0;
129
130
131 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
132 pthread_t os::Bsd::_main_thread;
133 int os::Bsd::_page_size = -1;
134
135 static jlong initial_time_count=0;
136
137 static int clock_tics_per_sec = 100;
138
139 // For diagnostics to print a message once. see run_periodic_checks
140 static sigset_t check_signal_done;
141 static bool check_signals = true;
142
143 static pid_t _initial_pid = 0;
144
145 /* Signal number used to suspend/resume a thread */
146
147 /* do not use any signal number less than SIGSEGV, see 4355769 */
148 static int SR_signum = SIGUSR2;
149 sigset_t SR_sigset;
150
151
152 ////////////////////////////////////////////////////////////////////////////////
153 // utility functions
154
155 static int SR_initialize();
156 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
157
158 julong os::available_memory() {
159 return Bsd::available_memory();
160 }
161
162 // available here means free
163 julong os::Bsd::available_memory() {
164 uint64_t available = physical_memory() >> 2;
165 #ifdef __APPLE__
166 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
167 vm_statistics64_data_t vmstat;
168 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
169 (host_info64_t)&vmstat, &count);
170 assert(kerr == KERN_SUCCESS,
171 "host_statistics64 failed - check mach_host_self() and count");
172 if (kerr == KERN_SUCCESS) {
173 available = vmstat.free_count * os::vm_page_size();
174 }
175 #endif
176 return available;
177 }
178
179 julong os::physical_memory() {
180 return Bsd::physical_memory();
181 }
182
183 ////////////////////////////////////////////////////////////////////////////////
184 // environment support
185
186 bool os::getenv(const char* name, char* buf, int len) {
187 const char* val = ::getenv(name);
188 if (val != NULL && strlen(val) < (size_t)len) {
189 strcpy(buf, val);
190 return true;
191 }
192 if (len > 0) buf[0] = 0; // return a null string
193 return false;
194 }
195
196
197 // Return true if user is running as root.
198
199 bool os::have_special_privileges() {
200 static bool init = false;
201 static bool privileges = false;
202 if (!init) {
203 privileges = (getuid() != geteuid()) || (getgid() != getegid());
204 init = true;
205 }
206 return privileges;
207 }
208
209
210
211 // Cpu architecture string
212 #if defined(ZERO)
213 static char cpu_arch[] = ZERO_LIBARCH;
214 #elif defined(IA64)
215 static char cpu_arch[] = "ia64";
216 #elif defined(IA32)
217 static char cpu_arch[] = "i386";
218 #elif defined(AMD64)
219 static char cpu_arch[] = "amd64";
220 #elif defined(ARM)
221 static char cpu_arch[] = "arm";
222 #elif defined(PPC)
223 static char cpu_arch[] = "ppc";
224 #elif defined(SPARC)
225 # ifdef _LP64
226 static char cpu_arch[] = "sparcv9";
227 # else
228 static char cpu_arch[] = "sparc";
229 # endif
230 #else
231 #error Add appropriate cpu_arch setting
232 #endif
233
234 // Compiler variant
235 #ifdef COMPILER2
236 #define COMPILER_VARIANT "server"
237 #else
238 #define COMPILER_VARIANT "client"
239 #endif
240
241
242 void os::Bsd::initialize_system_info() {
243 int mib[2];
244 size_t len;
245 int cpu_val;
246 julong mem_val;
247
248 /* get processors count via hw.ncpus sysctl */
249 mib[0] = CTL_HW;
250 mib[1] = HW_NCPU;
251 len = sizeof(cpu_val);
252 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
253 assert(len == sizeof(cpu_val), "unexpected data size");
254 set_processor_count(cpu_val);
255 }
256 else {
257 set_processor_count(1); // fallback
258 }
259
260 /* get physical memory via hw.memsize sysctl (hw.memsize is used
261 * since it returns a 64 bit value)
262 */
263 mib[0] = CTL_HW;
264
265 #if defined (HW_MEMSIZE) // Apple
266 mib[1] = HW_MEMSIZE;
267 #elif defined(HW_PHYSMEM) // Most of BSD
268 mib[1] = HW_PHYSMEM;
269 #elif defined(HW_REALMEM) // Old FreeBSD
270 mib[1] = HW_REALMEM;
271 #else
272 #error No ways to get physmem
273 #endif
274
275 len = sizeof(mem_val);
276 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
277 assert(len == sizeof(mem_val), "unexpected data size");
278 _physical_memory = mem_val;
279 } else {
280 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
281 }
282
283 #ifdef __OpenBSD__
284 {
285 // limit _physical_memory memory view on OpenBSD since
286 // datasize rlimit restricts us anyway.
287 struct rlimit limits;
288 getrlimit(RLIMIT_DATA, &limits);
289 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
290 }
291 #endif
292 }
293
294 #ifdef __APPLE__
295 static const char *get_home() {
296 const char *home_dir = ::getenv("HOME");
297 if ((home_dir == NULL) || (*home_dir == '\0')) {
298 struct passwd *passwd_info = getpwuid(geteuid());
299 if (passwd_info != NULL) {
300 home_dir = passwd_info->pw_dir;
301 }
302 }
303
304 return home_dir;
305 }
306 #endif
307
308 void os::init_system_properties_values() {
309 // char arch[12];
310 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
311
312 // The next steps are taken in the product version:
313 //
314 // Obtain the JAVA_HOME value from the location of libjvm.so.
315 // This library should be located at:
316 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
317 //
318 // If "/jre/lib/" appears at the right place in the path, then we
319 // assume libjvm.so is installed in a JDK and we use this path.
320 //
321 // Otherwise exit with message: "Could not create the Java virtual machine."
322 //
323 // The following extra steps are taken in the debugging version:
324 //
325 // If "/jre/lib/" does NOT appear at the right place in the path
326 // instead of exit check for $JAVA_HOME environment variable.
327 //
328 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
329 // then we append a fake suffix "hotspot/libjvm.so" to this path so
330 // it looks like libjvm.so is installed there
331 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
332 //
333 // Otherwise exit.
334 //
335 // Important note: if the location of libjvm.so changes this
336 // code needs to be changed accordingly.
337
338 // The next few definitions allow the code to be verbatim:
339 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
340 #define getenv(n) ::getenv(n)
341
342 /*
343 * See ld(1):
344 * The linker uses the following search paths to locate required
345 * shared libraries:
346 * 1: ...
347 * ...
348 * 7: The default directories, normally /lib and /usr/lib.
349 */
350 #ifndef DEFAULT_LIBPATH
351 #define DEFAULT_LIBPATH "/lib:/usr/lib"
352 #endif
353
354 #define EXTENSIONS_DIR "/lib/ext"
355 #define ENDORSED_DIR "/lib/endorsed"
356 #define REG_DIR "/usr/java/packages"
357
358 #ifdef __APPLE__
359 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
360 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
361 const char *user_home_dir = get_home();
362 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
363 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
364 sizeof(SYS_EXTENSIONS_DIRS);
365 #endif
366
367 {
368 /* sysclasspath, java_home, dll_dir */
369 {
370 char *home_path;
371 char *dll_path;
372 char *pslash;
373 char buf[MAXPATHLEN];
374 os::jvm_path(buf, sizeof(buf));
375
376 // Found the full path to libjvm.so.
377 // Now cut the path to <java_home>/jre if we can.
378 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
379 pslash = strrchr(buf, '/');
380 if (pslash != NULL)
381 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
382 dll_path = malloc(strlen(buf) + 1);
383 if (dll_path == NULL)
384 return;
385 strcpy(dll_path, buf);
386 Arguments::set_dll_dir(dll_path);
387
388 if (pslash != NULL) {
389 pslash = strrchr(buf, '/');
390 if (pslash != NULL) {
391 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
392 #ifndef __APPLE__
393 pslash = strrchr(buf, '/');
394 if (pslash != NULL)
395 *pslash = '\0'; /* get rid of /lib */
396 #endif
397 }
398 }
399
400 home_path = malloc(strlen(buf) + 1);
401 if (home_path == NULL)
402 return;
403 strcpy(home_path, buf);
404 Arguments::set_java_home(home_path);
405
406 if (!set_boot_path('/', ':'))
407 return;
408 }
409
410 /*
411 * Where to look for native libraries
412 *
413 * Note: Due to a legacy implementation, most of the library path
414 * is set in the launcher. This was to accomodate linking restrictions
415 * on legacy Bsd implementations (which are no longer supported).
416 * Eventually, all the library path setting will be done here.
417 *
418 * However, to prevent the proliferation of improperly built native
419 * libraries, the new path component /usr/java/packages is added here.
420 * Eventually, all the library path setting will be done here.
421 */
422 {
423 char *ld_library_path;
424
425 /*
426 * Construct the invariant part of ld_library_path. Note that the
427 * space for the colon and the trailing null are provided by the
428 * nulls included by the sizeof operator (so actually we allocate
429 * a byte more than necessary).
430 */
431 #ifdef __APPLE__
432 ld_library_path = (char *) malloc(system_ext_size);
433 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
434 #else
435 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
436 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
437 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
438 #endif
439
440 /*
441 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
442 * should always exist (until the legacy problem cited above is
443 * addressed).
444 */
445 #ifdef __APPLE__
446 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
447 char *l = getenv("JAVA_LIBRARY_PATH");
448 if (l != NULL) {
449 char *t = ld_library_path;
450 /* That's +1 for the colon and +1 for the trailing '\0' */
451 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
452 sprintf(ld_library_path, "%s:%s", l, t);
453 free(t);
454 }
455
456 char *v = getenv("DYLD_LIBRARY_PATH");
457 #else
458 char *v = getenv("LD_LIBRARY_PATH");
459 #endif
460 if (v != NULL) {
461 char *t = ld_library_path;
462 /* That's +1 for the colon and +1 for the trailing '\0' */
463 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
464 sprintf(ld_library_path, "%s:%s", v, t);
465 free(t);
466 }
467
468 #ifdef __APPLE__
469 // Apple's Java6 has "." at the beginning of java.library.path.
470 // OpenJDK on Windows has "." at the end of java.library.path.
471 // OpenJDK on Linux and Solaris don't have "." in java.library.path
472 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
473 // "." is appended to the end of java.library.path. Yes, this
474 // could cause a change in behavior, but Apple's Java6 behavior
475 // can be achieved by putting "." at the beginning of the
476 // JAVA_LIBRARY_PATH environment variable.
477 {
478 char *t = ld_library_path;
479 // that's +3 for appending ":." and the trailing '\0'
480 ld_library_path = (char *) malloc(strlen(t) + 3);
481 sprintf(ld_library_path, "%s:%s", t, ".");
482 free(t);
483 }
484 #endif
485
486 Arguments::set_library_path(ld_library_path);
487 }
488
489 /*
490 * Extensions directories.
491 *
492 * Note that the space for the colon and the trailing null are provided
493 * by the nulls included by the sizeof operator (so actually one byte more
494 * than necessary is allocated).
495 */
496 {
497 #ifdef __APPLE__
498 char *buf = malloc(strlen(Arguments::get_java_home()) +
499 sizeof(EXTENSIONS_DIR) + system_ext_size);
500 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
501 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
502 #else
503 char *buf = malloc(strlen(Arguments::get_java_home()) +
504 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
505 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
506 Arguments::get_java_home());
507 #endif
508
509 Arguments::set_ext_dirs(buf);
510 }
511
512 /* Endorsed standards default directory. */
513 {
514 char * buf;
515 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
516 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
517 Arguments::set_endorsed_dirs(buf);
518 }
519 }
520
521 #ifdef __APPLE__
522 #undef SYS_EXTENSIONS_DIR
523 #endif
524 #undef malloc
525 #undef getenv
526 #undef EXTENSIONS_DIR
527 #undef ENDORSED_DIR
528
529 // Done
530 return;
531 }
532
533 ////////////////////////////////////////////////////////////////////////////////
534 // breakpoint support
535
536 void os::breakpoint() {
537 BREAKPOINT;
538 }
539
540 extern "C" void breakpoint() {
541 // use debugger to set breakpoint here
542 }
543
544 ////////////////////////////////////////////////////////////////////////////////
545 // signal support
546
547 debug_only(static bool signal_sets_initialized = false);
548 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
549
550 bool os::Bsd::is_sig_ignored(int sig) {
551 struct sigaction oact;
552 sigaction(sig, (struct sigaction*)NULL, &oact);
553 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
554 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
555 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
556 return true;
557 else
558 return false;
559 }
560
561 void os::Bsd::signal_sets_init() {
562 // Should also have an assertion stating we are still single-threaded.
563 assert(!signal_sets_initialized, "Already initialized");
564 // Fill in signals that are necessarily unblocked for all threads in
565 // the VM. Currently, we unblock the following signals:
566 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
567 // by -Xrs (=ReduceSignalUsage));
568 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
569 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
570 // the dispositions or masks wrt these signals.
571 // Programs embedding the VM that want to use the above signals for their
572 // own purposes must, at this time, use the "-Xrs" option to prevent
573 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
574 // (See bug 4345157, and other related bugs).
575 // In reality, though, unblocking these signals is really a nop, since
576 // these signals are not blocked by default.
577 sigemptyset(&unblocked_sigs);
578 sigemptyset(&allowdebug_blocked_sigs);
579 sigaddset(&unblocked_sigs, SIGILL);
580 sigaddset(&unblocked_sigs, SIGSEGV);
581 sigaddset(&unblocked_sigs, SIGBUS);
582 sigaddset(&unblocked_sigs, SIGFPE);
583 sigaddset(&unblocked_sigs, SR_signum);
584
585 if (!ReduceSignalUsage) {
586 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
587 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
588 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
589 }
590 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
591 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
592 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
593 }
594 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
595 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
596 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
597 }
598 }
599 // Fill in signals that are blocked by all but the VM thread.
600 sigemptyset(&vm_sigs);
601 if (!ReduceSignalUsage)
602 sigaddset(&vm_sigs, BREAK_SIGNAL);
603 debug_only(signal_sets_initialized = true);
604
605 }
606
607 // These are signals that are unblocked while a thread is running Java.
608 // (For some reason, they get blocked by default.)
609 sigset_t* os::Bsd::unblocked_signals() {
610 assert(signal_sets_initialized, "Not initialized");
611 return &unblocked_sigs;
612 }
613
614 // These are the signals that are blocked while a (non-VM) thread is
615 // running Java. Only the VM thread handles these signals.
616 sigset_t* os::Bsd::vm_signals() {
617 assert(signal_sets_initialized, "Not initialized");
618 return &vm_sigs;
619 }
620
621 // These are signals that are blocked during cond_wait to allow debugger in
622 sigset_t* os::Bsd::allowdebug_blocked_signals() {
623 assert(signal_sets_initialized, "Not initialized");
624 return &allowdebug_blocked_sigs;
625 }
626
627 void os::Bsd::hotspot_sigmask(Thread* thread) {
628
629 //Save caller's signal mask before setting VM signal mask
630 sigset_t caller_sigmask;
631 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
632
633 OSThread* osthread = thread->osthread();
634 osthread->set_caller_sigmask(caller_sigmask);
635
636 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
637
638 if (!ReduceSignalUsage) {
639 if (thread->is_VM_thread()) {
640 // Only the VM thread handles BREAK_SIGNAL ...
641 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
642 } else {
643 // ... all other threads block BREAK_SIGNAL
644 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
645 }
646 }
647 }
648
649
650 //////////////////////////////////////////////////////////////////////////////
651 // create new thread
652
653 // check if it's safe to start a new thread
654 static bool _thread_safety_check(Thread* thread) {
655 return true;
656 }
657
658 #ifdef __APPLE__
659 // library handle for calling objc_registerThreadWithCollector()
660 // without static linking to the libobjc library
661 #define OBJC_LIB "/usr/lib/libobjc.dylib"
662 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
663 typedef void (*objc_registerThreadWithCollector_t)();
664 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
665 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
666 #endif
667
668 #ifdef __APPLE__
669 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
670 // Additional thread_id used to correlate threads in SA
671 thread_identifier_info_data_t m_ident_info;
672 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
673
674 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
675 (thread_info_t) &m_ident_info, &count);
676
677 return m_ident_info.thread_id;
678 }
679 #endif
680
681 // Thread start routine for all newly created threads
682 static void *java_start(Thread *thread) {
683 // Try to randomize the cache line index of hot stack frames.
684 // This helps when threads of the same stack traces evict each other's
685 // cache lines. The threads can be either from the same JVM instance, or
686 // from different JVM instances. The benefit is especially true for
687 // processors with hyperthreading technology.
688 static int counter = 0;
689 int pid = os::current_process_id();
690 alloca(((pid ^ counter++) & 7) * 128);
691
692 ThreadLocalStorage::set_thread(thread);
693
694 OSThread* osthread = thread->osthread();
695 Monitor* sync = osthread->startThread_lock();
696
697 // non floating stack BsdThreads needs extra check, see above
698 if (!_thread_safety_check(thread)) {
699 // notify parent thread
700 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
701 osthread->set_state(ZOMBIE);
702 sync->notify_all();
703 return NULL;
704 }
705
706 osthread->set_thread_id(os::Bsd::gettid());
707
708 #ifdef __APPLE__
709 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
710 guarantee(unique_thread_id != 0, "unique thread id was not found");
711 osthread->set_unique_thread_id(unique_thread_id);
712 #endif
713 // initialize signal mask for this thread
714 os::Bsd::hotspot_sigmask(thread);
715
716 // initialize floating point control register
717 os::Bsd::init_thread_fpu_state();
718
719 #ifdef __APPLE__
720 // register thread with objc gc
721 if (objc_registerThreadWithCollectorFunction != NULL) {
722 objc_registerThreadWithCollectorFunction();
723 }
724 #endif
725
726 // handshaking with parent thread
727 {
728 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
729
730 // notify parent thread
731 osthread->set_state(INITIALIZED);
732 sync->notify_all();
733
734 // wait until os::start_thread()
735 while (osthread->get_state() == INITIALIZED) {
736 sync->wait(Mutex::_no_safepoint_check_flag);
737 }
738 }
739
740 // call one more level start routine
741 thread->run();
742
743 return 0;
744 }
745
746 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
747 assert(thread->osthread() == NULL, "caller responsible");
748
749 // Allocate the OSThread object
750 OSThread* osthread = new OSThread(NULL, NULL);
751 if (osthread == NULL) {
752 return false;
753 }
754
755 // set the correct thread state
756 osthread->set_thread_type(thr_type);
757
758 // Initial state is ALLOCATED but not INITIALIZED
759 osthread->set_state(ALLOCATED);
760
761 thread->set_osthread(osthread);
762
763 // init thread attributes
764 pthread_attr_t attr;
765 pthread_attr_init(&attr);
766 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
767
768 // stack size
769 if (os::Bsd::supports_variable_stack_size()) {
770 // calculate stack size if it's not specified by caller
771 if (stack_size == 0) {
772 stack_size = os::Bsd::default_stack_size(thr_type);
773
774 switch (thr_type) {
775 case os::java_thread:
776 // Java threads use ThreadStackSize which default value can be
777 // changed with the flag -Xss
778 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
779 stack_size = JavaThread::stack_size_at_create();
780 break;
781 case os::compiler_thread:
782 if (CompilerThreadStackSize > 0) {
783 stack_size = (size_t)(CompilerThreadStackSize * K);
784 break;
785 } // else fall through:
786 // use VMThreadStackSize if CompilerThreadStackSize is not defined
787 case os::vm_thread:
788 case os::pgc_thread:
789 case os::cgc_thread:
790 case os::watcher_thread:
791 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
792 break;
793 }
794 }
795
796 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
797 pthread_attr_setstacksize(&attr, stack_size);
798 } else {
799 // let pthread_create() pick the default value.
800 }
801
802 ThreadState state;
803
804 {
805 pthread_t tid;
806 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
807
808 pthread_attr_destroy(&attr);
809
810 if (ret != 0) {
811 if (PrintMiscellaneous && (Verbose || WizardMode)) {
812 perror("pthread_create()");
813 }
814 // Need to clean up stuff we've allocated so far
815 thread->set_osthread(NULL);
816 delete osthread;
817 return false;
818 }
819
820 // Store pthread info into the OSThread
821 osthread->set_pthread_id(tid);
822
823 // Wait until child thread is either initialized or aborted
824 {
825 Monitor* sync_with_child = osthread->startThread_lock();
826 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
827 while ((state = osthread->get_state()) == ALLOCATED) {
828 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
829 }
830 }
831
832 }
833
834 // Aborted due to thread limit being reached
835 if (state == ZOMBIE) {
836 thread->set_osthread(NULL);
837 delete osthread;
838 return false;
839 }
840
841 // The thread is returned suspended (in state INITIALIZED),
842 // and is started higher up in the call chain
843 assert(state == INITIALIZED, "race condition");
844 return true;
845 }
846
847 /////////////////////////////////////////////////////////////////////////////
848 // attach existing thread
849
850 // bootstrap the main thread
851 bool os::create_main_thread(JavaThread* thread) {
852 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
853 return create_attached_thread(thread);
854 }
855
856 bool os::create_attached_thread(JavaThread* thread) {
857 #ifdef ASSERT
858 thread->verify_not_published();
859 #endif
860
861 // Allocate the OSThread object
862 OSThread* osthread = new OSThread(NULL, NULL);
863
864 if (osthread == NULL) {
865 return false;
866 }
867
868 osthread->set_thread_id(os::Bsd::gettid());
869
870 // Store pthread info into the OSThread
871 #ifdef __APPLE__
872 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
873 guarantee(unique_thread_id != 0, "just checking");
874 osthread->set_unique_thread_id(unique_thread_id);
875 #endif
876 osthread->set_pthread_id(::pthread_self());
877
878 // initialize floating point control register
879 os::Bsd::init_thread_fpu_state();
880
881 // Initial thread state is RUNNABLE
882 osthread->set_state(RUNNABLE);
883
884 thread->set_osthread(osthread);
885
886 // initialize signal mask for this thread
887 // and save the caller's signal mask
888 os::Bsd::hotspot_sigmask(thread);
889
890 return true;
891 }
892
893 void os::pd_start_thread(Thread* thread) {
894 OSThread * osthread = thread->osthread();
895 assert(osthread->get_state() != INITIALIZED, "just checking");
896 Monitor* sync_with_child = osthread->startThread_lock();
897 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
898 sync_with_child->notify();
899 }
900
901 // Free Bsd resources related to the OSThread
902 void os::free_thread(OSThread* osthread) {
903 assert(osthread != NULL, "osthread not set");
904
905 if (Thread::current()->osthread() == osthread) {
906 // Restore caller's signal mask
907 sigset_t sigmask = osthread->caller_sigmask();
908 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
909 }
910
911 delete osthread;
912 }
913
914 //////////////////////////////////////////////////////////////////////////////
915 // thread local storage
916
917 int os::allocate_thread_local_storage() {
918 pthread_key_t key;
919 int rslt = pthread_key_create(&key, NULL);
920 assert(rslt == 0, "cannot allocate thread local storage");
921 return (int)key;
922 }
923
924 // Note: This is currently not used by VM, as we don't destroy TLS key
925 // on VM exit.
926 void os::free_thread_local_storage(int index) {
927 int rslt = pthread_key_delete((pthread_key_t)index);
928 assert(rslt == 0, "invalid index");
929 }
930
931 void os::thread_local_storage_at_put(int index, void* value) {
932 int rslt = pthread_setspecific((pthread_key_t)index, value);
933 assert(rslt == 0, "pthread_setspecific failed");
934 }
935
936 extern "C" Thread* get_thread() {
937 return ThreadLocalStorage::thread();
938 }
939
940
941 ////////////////////////////////////////////////////////////////////////////////
942 // time support
943
944 // Time since start-up in seconds to a fine granularity.
945 // Used by VMSelfDestructTimer and the MemProfiler.
946 double os::elapsedTime() {
947
948 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
949 }
950
951 jlong os::elapsed_counter() {
952 return javaTimeNanos() - initial_time_count;
953 }
954
955 jlong os::elapsed_frequency() {
956 return NANOSECS_PER_SEC; // nanosecond resolution
957 }
958
959 bool os::supports_vtime() { return true; }
960 bool os::enable_vtime() { return false; }
961 bool os::vtime_enabled() { return false; }
962
963 double os::elapsedVTime() {
964 // better than nothing, but not much
965 return elapsedTime();
966 }
967
968 jlong os::javaTimeMillis() {
969 timeval time;
970 int status = gettimeofday(&time, NULL);
971 assert(status != -1, "bsd error");
972 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
973 }
974
975 #ifndef CLOCK_MONOTONIC
976 #define CLOCK_MONOTONIC (1)
977 #endif
978
979 #ifdef __APPLE__
980 void os::Bsd::clock_init() {
981 // XXXDARWIN: Investigate replacement monotonic clock
982 }
983 #else
984 void os::Bsd::clock_init() {
985 struct timespec res;
986 struct timespec tp;
987 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
988 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
989 // yes, monotonic clock is supported
990 _clock_gettime = ::clock_gettime;
991 }
992 }
993 #endif
994
995
996 jlong os::javaTimeNanos() {
997 if (Bsd::supports_monotonic_clock()) {
998 struct timespec tp;
999 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1000 assert(status == 0, "gettime error");
1001 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1002 return result;
1003 } else {
1004 timeval time;
1005 int status = gettimeofday(&time, NULL);
1006 assert(status != -1, "bsd error");
1007 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1008 return 1000 * usecs;
1009 }
1010 }
1011
1012 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1013 if (Bsd::supports_monotonic_clock()) {
1014 info_ptr->max_value = ALL_64_BITS;
1015
1016 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1017 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1018 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1019 } else {
1020 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1021 info_ptr->max_value = ALL_64_BITS;
1022
1023 // gettimeofday is a real time clock so it skips
1024 info_ptr->may_skip_backward = true;
1025 info_ptr->may_skip_forward = true;
1026 }
1027
1028 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1029 }
1030
1031 // Return the real, user, and system times in seconds from an
1032 // arbitrary fixed point in the past.
1033 bool os::getTimesSecs(double* process_real_time,
1034 double* process_user_time,
1035 double* process_system_time) {
1036 struct tms ticks;
1037 clock_t real_ticks = times(&ticks);
1038
1039 if (real_ticks == (clock_t) (-1)) {
1040 return false;
1041 } else {
1042 double ticks_per_second = (double) clock_tics_per_sec;
1043 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1044 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1045 *process_real_time = ((double) real_ticks) / ticks_per_second;
1046
1047 return true;
1048 }
1049 }
1050
1051
1052 char * os::local_time_string(char *buf, size_t buflen) {
1053 struct tm t;
1054 time_t long_time;
1055 time(&long_time);
1056 localtime_r(&long_time, &t);
1057 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1058 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1059 t.tm_hour, t.tm_min, t.tm_sec);
1060 return buf;
1061 }
1062
1063 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1064 return localtime_r(clock, res);
1065 }
1066
1067 ////////////////////////////////////////////////////////////////////////////////
1068 // runtime exit support
1069
1070 // Note: os::shutdown() might be called very early during initialization, or
1071 // called from signal handler. Before adding something to os::shutdown(), make
1072 // sure it is async-safe and can handle partially initialized VM.
1073 void os::shutdown() {
1074
1075 // allow PerfMemory to attempt cleanup of any persistent resources
1076 perfMemory_exit();
1077
1078 // needs to remove object in file system
1079 AttachListener::abort();
1080
1081 // flush buffered output, finish log files
1082 ostream_abort();
1083
1084 // Check for abort hook
1085 abort_hook_t abort_hook = Arguments::abort_hook();
1086 if (abort_hook != NULL) {
1087 abort_hook();
1088 }
1089
1090 }
1091
1092 // Note: os::abort() might be called very early during initialization, or
1093 // called from signal handler. Before adding something to os::abort(), make
1094 // sure it is async-safe and can handle partially initialized VM.
1095 void os::abort(bool dump_core) {
1096 os::shutdown();
1097 if (dump_core) {
1098 #ifndef PRODUCT
1099 fdStream out(defaultStream::output_fd());
1100 out.print_raw("Current thread is ");
1101 char buf[16];
1102 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1103 out.print_raw_cr(buf);
1104 out.print_raw_cr("Dumping core ...");
1105 #endif
1106 ::abort(); // dump core
1107 }
1108
1109 ::exit(1);
1110 }
1111
1112 // Die immediately, no exit hook, no abort hook, no cleanup.
1113 void os::die() {
1114 // _exit() on BsdThreads only kills current thread
1115 ::abort();
1116 }
1117
1118 // unused on bsd for now.
1119 void os::set_error_file(const char *logfile) {}
1120
1121
1122 // This method is a copy of JDK's sysGetLastErrorString
1123 // from src/solaris/hpi/src/system_md.c
1124
1125 size_t os::lasterror(char *buf, size_t len) {
1126
1127 if (errno == 0) return 0;
1128
1129 const char *s = ::strerror(errno);
1130 size_t n = ::strlen(s);
1131 if (n >= len) {
1132 n = len - 1;
1133 }
1134 ::strncpy(buf, s, n);
1135 buf[n] = '\0';
1136 return n;
1137 }
1138
1139 // Information of current thread in variety of formats
1140 pid_t os::Bsd::gettid() {
1141 int retval = -1;
1142
1143 #ifdef __APPLE__ //XNU kernel
1144 // despite the fact mach port is actually not a thread id use it
1145 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1146 retval = ::pthread_mach_thread_np(::pthread_self());
1147 guarantee(retval != 0, "just checking");
1148 return retval;
1149
1150 #elif __FreeBSD__
1151 retval = syscall(SYS_thr_self);
1152 #elif __OpenBSD__
1153 retval = syscall(SYS_getthrid);
1154 #elif __NetBSD__
1155 retval = (pid_t) syscall(SYS__lwp_self);
1156 #endif
1157
1158 if (retval == -1) {
1159 return getpid();
1160 }
1161 }
1162
1163 intx os::current_thread_id() {
1164 #ifdef __APPLE__
1165 return (intx)::pthread_mach_thread_np(::pthread_self());
1166 #else
1167 return (intx)::pthread_self();
1168 #endif
1169 }
1170
1171 int os::current_process_id() {
1172
1173 // Under the old bsd thread library, bsd gives each thread
1174 // its own process id. Because of this each thread will return
1175 // a different pid if this method were to return the result
1176 // of getpid(2). Bsd provides no api that returns the pid
1177 // of the launcher thread for the vm. This implementation
1178 // returns a unique pid, the pid of the launcher thread
1179 // that starts the vm 'process'.
1180
1181 // Under the NPTL, getpid() returns the same pid as the
1182 // launcher thread rather than a unique pid per thread.
1183 // Use gettid() if you want the old pre NPTL behaviour.
1184
1185 // if you are looking for the result of a call to getpid() that
1186 // returns a unique pid for the calling thread, then look at the
1187 // OSThread::thread_id() method in osThread_bsd.hpp file
1188
1189 return (int)(_initial_pid ? _initial_pid : getpid());
1190 }
1191
1192 // DLL functions
1193
1194 #define JNI_LIB_PREFIX "lib"
1195 #ifdef __APPLE__
1196 #define JNI_LIB_SUFFIX ".dylib"
1197 #else
1198 #define JNI_LIB_SUFFIX ".so"
1199 #endif
1200
1201 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1202
1203 // This must be hard coded because it's the system's temporary
1204 // directory not the java application's temp directory, ala java.io.tmpdir.
1205 #ifdef __APPLE__
1206 // macosx has a secure per-user temporary directory
1207 char temp_path_storage[PATH_MAX];
1208 const char* os::get_temp_directory() {
1209 static char *temp_path = NULL;
1210 if (temp_path == NULL) {
1211 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1212 if (pathSize == 0 || pathSize > PATH_MAX) {
1213 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1214 }
1215 temp_path = temp_path_storage;
1216 }
1217 return temp_path;
1218 }
1219 #else /* __APPLE__ */
1220 const char* os::get_temp_directory() { return "/tmp"; }
1221 #endif /* __APPLE__ */
1222
1223 static bool file_exists(const char* filename) {
1224 struct stat statbuf;
1225 if (filename == NULL || strlen(filename) == 0) {
1226 return false;
1227 }
1228 return os::stat(filename, &statbuf) == 0;
1229 }
1230
1231 bool os::dll_build_name(char* buffer, size_t buflen,
1232 const char* pname, const char* fname) {
1233 bool retval = false;
1234 // Copied from libhpi
1235 const size_t pnamelen = pname ? strlen(pname) : 0;
1236
1237 // Return error on buffer overflow.
1238 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1239 return retval;
1240 }
1241
1242 if (pnamelen == 0) {
1243 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1244 retval = true;
1245 } else if (strchr(pname, *os::path_separator()) != NULL) {
1246 int n;
1247 char** pelements = split_path(pname, &n);
1248 if (pelements == NULL) {
1249 return false;
1250 }
1251 for (int i = 0 ; i < n ; i++) {
1252 // Really shouldn't be NULL, but check can't hurt
1253 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1254 continue; // skip the empty path values
1255 }
1256 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1257 pelements[i], fname);
1258 if (file_exists(buffer)) {
1259 retval = true;
1260 break;
1261 }
1262 }
1263 // release the storage
1264 for (int i = 0 ; i < n ; i++) {
1265 if (pelements[i] != NULL) {
1266 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1267 }
1268 }
1269 if (pelements != NULL) {
1270 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1271 }
1272 } else {
1273 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1274 retval = true;
1275 }
1276 return retval;
1277 }
1278
1279 // check if addr is inside libjvm.so
1280 bool os::address_is_in_vm(address addr) {
1281 static address libjvm_base_addr;
1282 Dl_info dlinfo;
1283
1284 if (libjvm_base_addr == NULL) {
1285 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1286 libjvm_base_addr = (address)dlinfo.dli_fbase;
1287 }
1288 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1289 }
1290
1291 if (dladdr((void *)addr, &dlinfo) != 0) {
1292 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1293 }
1294
1295 return false;
1296 }
1297
1298
1299 #define MACH_MAXSYMLEN 256
1300
1301 bool os::dll_address_to_function_name(address addr, char *buf,
1302 int buflen, int *offset) {
1303 // buf is not optional, but offset is optional
1304 assert(buf != NULL, "sanity check");
1305
1306 Dl_info dlinfo;
1307 char localbuf[MACH_MAXSYMLEN];
1308
1309 if (dladdr((void*)addr, &dlinfo) != 0) {
1310 // see if we have a matching symbol
1311 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1312 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1313 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1314 }
1315 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1316 return true;
1317 }
1318 // no matching symbol so try for just file info
1319 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1320 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1321 buf, buflen, offset, dlinfo.dli_fname)) {
1322 return true;
1323 }
1324 }
1325
1326 // Handle non-dynamic manually:
1327 if (dlinfo.dli_fbase != NULL &&
1328 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1329 dlinfo.dli_fbase)) {
1330 if (!Decoder::demangle(localbuf, buf, buflen)) {
1331 jio_snprintf(buf, buflen, "%s", localbuf);
1332 }
1333 return true;
1334 }
1335 }
1336 buf[0] = '\0';
1337 if (offset != NULL) *offset = -1;
1338 return false;
1339 }
1340
1341 // ported from solaris version
1342 bool os::dll_address_to_library_name(address addr, char* buf,
1343 int buflen, int* offset) {
1344 // buf is not optional, but offset is optional
1345 assert(buf != NULL, "sanity check");
1346
1347 Dl_info dlinfo;
1348
1349 if (dladdr((void*)addr, &dlinfo) != 0) {
1350 if (dlinfo.dli_fname != NULL) {
1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1352 }
1353 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1354 *offset = addr - (address)dlinfo.dli_fbase;
1355 }
1356 return true;
1357 }
1358
1359 buf[0] = '\0';
1360 if (offset) *offset = -1;
1361 return false;
1362 }
1363
1364 // Loads .dll/.so and
1365 // in case of error it checks if .dll/.so was built for the
1366 // same architecture as Hotspot is running on
1367
1368 #ifdef __APPLE__
1369 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1370 void * result= ::dlopen(filename, RTLD_LAZY);
1371 if (result != NULL) {
1372 // Successful loading
1373 return result;
1374 }
1375
1376 // Read system error message into ebuf
1377 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1378 ebuf[ebuflen-1]='\0';
1379
1380 return NULL;
1381 }
1382 #else
1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1384 {
1385 void * result= ::dlopen(filename, RTLD_LAZY);
1386 if (result != NULL) {
1387 // Successful loading
1388 return result;
1389 }
1390
1391 Elf32_Ehdr elf_head;
1392
1393 // Read system error message into ebuf
1394 // It may or may not be overwritten below
1395 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1396 ebuf[ebuflen-1]='\0';
1397 int diag_msg_max_length=ebuflen-strlen(ebuf);
1398 char* diag_msg_buf=ebuf+strlen(ebuf);
1399
1400 if (diag_msg_max_length==0) {
1401 // No more space in ebuf for additional diagnostics message
1402 return NULL;
1403 }
1404
1405
1406 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1407
1408 if (file_descriptor < 0) {
1409 // Can't open library, report dlerror() message
1410 return NULL;
1411 }
1412
1413 bool failed_to_read_elf_head=
1414 (sizeof(elf_head)!=
1415 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1416
1417 ::close(file_descriptor);
1418 if (failed_to_read_elf_head) {
1419 // file i/o error - report dlerror() msg
1420 return NULL;
1421 }
1422
1423 typedef struct {
1424 Elf32_Half code; // Actual value as defined in elf.h
1425 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1426 char elf_class; // 32 or 64 bit
1427 char endianess; // MSB or LSB
1428 char* name; // String representation
1429 } arch_t;
1430
1431 #ifndef EM_486
1432 #define EM_486 6 /* Intel 80486 */
1433 #endif
1434
1435 #ifndef EM_MIPS_RS3_LE
1436 #define EM_MIPS_RS3_LE 10 /* MIPS */
1437 #endif
1438
1439 #ifndef EM_PPC64
1440 #define EM_PPC64 21 /* PowerPC64 */
1441 #endif
1442
1443 #ifndef EM_S390
1444 #define EM_S390 22 /* IBM System/390 */
1445 #endif
1446
1447 #ifndef EM_IA_64
1448 #define EM_IA_64 50 /* HP/Intel IA-64 */
1449 #endif
1450
1451 #ifndef EM_X86_64
1452 #define EM_X86_64 62 /* AMD x86-64 */
1453 #endif
1454
1455 static const arch_t arch_array[]={
1456 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1457 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1458 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1459 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1460 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1461 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1462 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1463 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1464 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1465 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1466 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1467 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1468 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1469 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1470 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1471 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1472 };
1473
1474 #if (defined IA32)
1475 static Elf32_Half running_arch_code=EM_386;
1476 #elif (defined AMD64)
1477 static Elf32_Half running_arch_code=EM_X86_64;
1478 #elif (defined IA64)
1479 static Elf32_Half running_arch_code=EM_IA_64;
1480 #elif (defined __sparc) && (defined _LP64)
1481 static Elf32_Half running_arch_code=EM_SPARCV9;
1482 #elif (defined __sparc) && (!defined _LP64)
1483 static Elf32_Half running_arch_code=EM_SPARC;
1484 #elif (defined __powerpc64__)
1485 static Elf32_Half running_arch_code=EM_PPC64;
1486 #elif (defined __powerpc__)
1487 static Elf32_Half running_arch_code=EM_PPC;
1488 #elif (defined ARM)
1489 static Elf32_Half running_arch_code=EM_ARM;
1490 #elif (defined S390)
1491 static Elf32_Half running_arch_code=EM_S390;
1492 #elif (defined ALPHA)
1493 static Elf32_Half running_arch_code=EM_ALPHA;
1494 #elif (defined MIPSEL)
1495 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1496 #elif (defined PARISC)
1497 static Elf32_Half running_arch_code=EM_PARISC;
1498 #elif (defined MIPS)
1499 static Elf32_Half running_arch_code=EM_MIPS;
1500 #elif (defined M68K)
1501 static Elf32_Half running_arch_code=EM_68K;
1502 #else
1503 #error Method os::dll_load requires that one of following is defined:\
1504 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1505 #endif
1506
1507 // Identify compatability class for VM's architecture and library's architecture
1508 // Obtain string descriptions for architectures
1509
1510 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1511 int running_arch_index=-1;
1512
1513 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1514 if (running_arch_code == arch_array[i].code) {
1515 running_arch_index = i;
1516 }
1517 if (lib_arch.code == arch_array[i].code) {
1518 lib_arch.compat_class = arch_array[i].compat_class;
1519 lib_arch.name = arch_array[i].name;
1520 }
1521 }
1522
1523 assert(running_arch_index != -1,
1524 "Didn't find running architecture code (running_arch_code) in arch_array");
1525 if (running_arch_index == -1) {
1526 // Even though running architecture detection failed
1527 // we may still continue with reporting dlerror() message
1528 return NULL;
1529 }
1530
1531 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1532 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1533 return NULL;
1534 }
1535
1536 #ifndef S390
1537 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1539 return NULL;
1540 }
1541 #endif // !S390
1542
1543 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1544 if ( lib_arch.name!=NULL ) {
1545 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1546 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1547 lib_arch.name, arch_array[running_arch_index].name);
1548 } else {
1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1550 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1551 lib_arch.code,
1552 arch_array[running_arch_index].name);
1553 }
1554 }
1555
1556 return NULL;
1557 }
1558 #endif /* !__APPLE__ */
1559
1560 void* os::get_default_process_handle() {
1561 #ifdef __APPLE__
1562 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1563 // to avoid finding unexpected symbols on second (or later)
1564 // loads of a library.
1565 return (void*)::dlopen(NULL, RTLD_FIRST);
1566 #else
1567 return (void*)::dlopen(NULL, RTLD_LAZY);
1568 #endif
1569 }
1570
1571 // XXX: Do we need a lock around this as per Linux?
1572 void* os::dll_lookup(void* handle, const char* name) {
1573 return dlsym(handle, name);
1574 }
1575
1576
1577 static bool _print_ascii_file(const char* filename, outputStream* st) {
1578 int fd = ::open(filename, O_RDONLY);
1579 if (fd == -1) {
1580 return false;
1581 }
1582
1583 char buf[32];
1584 int bytes;
1585 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1586 st->print_raw(buf, bytes);
1587 }
1588
1589 ::close(fd);
1590
1591 return true;
1592 }
1593
1594 void os::print_dll_info(outputStream *st) {
1595 st->print_cr("Dynamic libraries:");
1596 #ifdef RTLD_DI_LINKMAP
1597 Dl_info dli;
1598 void *handle;
1599 Link_map *map;
1600 Link_map *p;
1601
1602 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1603 dli.dli_fname == NULL) {
1604 st->print_cr("Error: Cannot print dynamic libraries.");
1605 return;
1606 }
1607 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1608 if (handle == NULL) {
1609 st->print_cr("Error: Cannot print dynamic libraries.");
1610 return;
1611 }
1612 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1613 if (map == NULL) {
1614 st->print_cr("Error: Cannot print dynamic libraries.");
1615 return;
1616 }
1617
1618 while (map->l_prev != NULL)
1619 map = map->l_prev;
1620
1621 while (map != NULL) {
1622 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1623 map = map->l_next;
1624 }
1625
1626 dlclose(handle);
1627 #elif defined(__APPLE__)
1628 uint32_t count;
1629 uint32_t i;
1630
1631 count = _dyld_image_count();
1632 for (i = 1; i < count; i++) {
1633 const char *name = _dyld_get_image_name(i);
1634 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1635 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1636 }
1637 #else
1638 st->print_cr("Error: Cannot print dynamic libraries.");
1639 #endif
1640 }
1641
1642 void os::print_os_info_brief(outputStream* st) {
1643 st->print("Bsd");
1644
1645 os::Posix::print_uname_info(st);
1646 }
1647
1648 void os::print_os_info(outputStream* st) {
1649 st->print("OS:");
1650 st->print("Bsd");
1651
1652 os::Posix::print_uname_info(st);
1653
1654 os::Posix::print_rlimit_info(st);
1655
1656 os::Posix::print_load_average(st);
1657 }
1658
1659 void os::pd_print_cpu_info(outputStream* st) {
1660 // Nothing to do for now.
1661 }
1662
1663 void os::print_memory_info(outputStream* st) {
1664
1665 st->print("Memory:");
1666 st->print(" %dk page", os::vm_page_size()>>10);
1667
1668 st->print(", physical " UINT64_FORMAT "k",
1669 os::physical_memory() >> 10);
1670 st->print("(" UINT64_FORMAT "k free)",
1671 os::available_memory() >> 10);
1672 st->cr();
1673
1674 // meminfo
1675 st->print("\n/proc/meminfo:\n");
1676 _print_ascii_file("/proc/meminfo", st);
1677 st->cr();
1678 }
1679
1680 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1681 // but they're the same for all the bsd arch that we support
1682 // and they're the same for solaris but there's no common place to put this.
1683 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1684 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1685 "ILL_COPROC", "ILL_BADSTK" };
1686
1687 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1688 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1689 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1690
1691 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1692
1693 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1694
1695 void os::print_siginfo(outputStream* st, void* siginfo) {
1696 st->print("siginfo:");
1697
1698 const int buflen = 100;
1699 char buf[buflen];
1700 siginfo_t *si = (siginfo_t*)siginfo;
1701 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1702 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1703 st->print("si_errno=%s", buf);
1704 } else {
1705 st->print("si_errno=%d", si->si_errno);
1706 }
1707 const int c = si->si_code;
1708 assert(c > 0, "unexpected si_code");
1709 switch (si->si_signo) {
1710 case SIGILL:
1711 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1712 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1713 break;
1714 case SIGFPE:
1715 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1716 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1717 break;
1718 case SIGSEGV:
1719 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1720 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1721 break;
1722 case SIGBUS:
1723 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1724 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1725 break;
1726 default:
1727 st->print(", si_code=%d", si->si_code);
1728 // no si_addr
1729 }
1730
1731 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1732 UseSharedSpaces) {
1733 FileMapInfo* mapinfo = FileMapInfo::current_info();
1734 if (mapinfo->is_in_shared_space(si->si_addr)) {
1735 st->print("\n\nError accessing class data sharing archive." \
1736 " Mapped file inaccessible during execution, " \
1737 " possible disk/network problem.");
1738 }
1739 }
1740 st->cr();
1741 }
1742
1743
1744 static void print_signal_handler(outputStream* st, int sig,
1745 char* buf, size_t buflen);
1746
1747 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1748 st->print_cr("Signal Handlers:");
1749 print_signal_handler(st, SIGSEGV, buf, buflen);
1750 print_signal_handler(st, SIGBUS , buf, buflen);
1751 print_signal_handler(st, SIGFPE , buf, buflen);
1752 print_signal_handler(st, SIGPIPE, buf, buflen);
1753 print_signal_handler(st, SIGXFSZ, buf, buflen);
1754 print_signal_handler(st, SIGILL , buf, buflen);
1755 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1756 print_signal_handler(st, SR_signum, buf, buflen);
1757 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1758 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1759 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1760 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1761 }
1762
1763 static char saved_jvm_path[MAXPATHLEN] = {0};
1764
1765 // Find the full path to the current module, libjvm
1766 void os::jvm_path(char *buf, jint buflen) {
1767 // Error checking.
1768 if (buflen < MAXPATHLEN) {
1769 assert(false, "must use a large-enough buffer");
1770 buf[0] = '\0';
1771 return;
1772 }
1773 // Lazy resolve the path to current module.
1774 if (saved_jvm_path[0] != 0) {
1775 strcpy(buf, saved_jvm_path);
1776 return;
1777 }
1778
1779 char dli_fname[MAXPATHLEN];
1780 bool ret = dll_address_to_library_name(
1781 CAST_FROM_FN_PTR(address, os::jvm_path),
1782 dli_fname, sizeof(dli_fname), NULL);
1783 assert(ret, "cannot locate libjvm");
1784 char *rp = NULL;
1785 if (ret && dli_fname[0] != '\0') {
1786 rp = realpath(dli_fname, buf);
1787 }
1788 if (rp == NULL)
1789 return;
1790
1791 if (Arguments::sun_java_launcher_is_altjvm()) {
1792 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1793 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1794 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1795 // appears at the right place in the string, then assume we are
1796 // installed in a JDK and we're done. Otherwise, check for a
1797 // JAVA_HOME environment variable and construct a path to the JVM
1798 // being overridden.
1799
1800 const char *p = buf + strlen(buf) - 1;
1801 for (int count = 0; p > buf && count < 5; ++count) {
1802 for (--p; p > buf && *p != '/'; --p)
1803 /* empty */ ;
1804 }
1805
1806 if (strncmp(p, "/jre/lib/", 9) != 0) {
1807 // Look for JAVA_HOME in the environment.
1808 char* java_home_var = ::getenv("JAVA_HOME");
1809 if (java_home_var != NULL && java_home_var[0] != 0) {
1810 char* jrelib_p;
1811 int len;
1812
1813 // Check the current module name "libjvm"
1814 p = strrchr(buf, '/');
1815 assert(strstr(p, "/libjvm") == p, "invalid library name");
1816
1817 rp = realpath(java_home_var, buf);
1818 if (rp == NULL)
1819 return;
1820
1821 // determine if this is a legacy image or modules image
1822 // modules image doesn't have "jre" subdirectory
1823 len = strlen(buf);
1824 jrelib_p = buf + len;
1825
1826 // Add the appropriate library subdir
1827 snprintf(jrelib_p, buflen-len, "/jre/lib");
1828 if (0 != access(buf, F_OK)) {
1829 snprintf(jrelib_p, buflen-len, "/lib");
1830 }
1831
1832 // Add the appropriate client or server subdir
1833 len = strlen(buf);
1834 jrelib_p = buf + len;
1835 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1836 if (0 != access(buf, F_OK)) {
1837 snprintf(jrelib_p, buflen-len, "%s", "");
1838 }
1839
1840 // If the path exists within JAVA_HOME, add the JVM library name
1841 // to complete the path to JVM being overridden. Otherwise fallback
1842 // to the path to the current library.
1843 if (0 == access(buf, F_OK)) {
1844 // Use current module name "libjvm"
1845 len = strlen(buf);
1846 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1847 } else {
1848 // Fall back to path of current library
1849 rp = realpath(dli_fname, buf);
1850 if (rp == NULL)
1851 return;
1852 }
1853 }
1854 }
1855 }
1856
1857 strcpy(saved_jvm_path, buf);
1858 }
1859
1860 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1861 // no prefix required, not even "_"
1862 }
1863
1864 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1865 // no suffix required
1866 }
1867
1868 ////////////////////////////////////////////////////////////////////////////////
1869 // sun.misc.Signal support
1870
1871 static volatile jint sigint_count = 0;
1872
1873 static void
1874 UserHandler(int sig, void *siginfo, void *context) {
1875 // 4511530 - sem_post is serialized and handled by the manager thread. When
1876 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1877 // don't want to flood the manager thread with sem_post requests.
1878 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1879 return;
1880
1881 // Ctrl-C is pressed during error reporting, likely because the error
1882 // handler fails to abort. Let VM die immediately.
1883 if (sig == SIGINT && is_error_reported()) {
1884 os::die();
1885 }
1886
1887 os::signal_notify(sig);
1888 }
1889
1890 void* os::user_handler() {
1891 return CAST_FROM_FN_PTR(void*, UserHandler);
1892 }
1893
1894 extern "C" {
1895 typedef void (*sa_handler_t)(int);
1896 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1897 }
1898
1899 void* os::signal(int signal_number, void* handler) {
1900 struct sigaction sigAct, oldSigAct;
1901
1902 sigfillset(&(sigAct.sa_mask));
1903 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1904 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1905
1906 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1907 // -1 means registration failed
1908 return (void *)-1;
1909 }
1910
1911 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1912 }
1913
1914 void os::signal_raise(int signal_number) {
1915 ::raise(signal_number);
1916 }
1917
1918 /*
1919 * The following code is moved from os.cpp for making this
1920 * code platform specific, which it is by its very nature.
1921 */
1922
1923 // Will be modified when max signal is changed to be dynamic
1924 int os::sigexitnum_pd() {
1925 return NSIG;
1926 }
1927
1928 // a counter for each possible signal value
1929 static volatile jint pending_signals[NSIG+1] = { 0 };
1930
1931 // Bsd(POSIX) specific hand shaking semaphore.
1932 #ifdef __APPLE__
1933 typedef semaphore_t os_semaphore_t;
1934 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1935 #define SEM_WAIT(sem) semaphore_wait(sem)
1936 #define SEM_POST(sem) semaphore_signal(sem)
1937 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1938 #else
1939 typedef sem_t os_semaphore_t;
1940 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1941 #define SEM_WAIT(sem) sem_wait(&sem)
1942 #define SEM_POST(sem) sem_post(&sem)
1943 #define SEM_DESTROY(sem) sem_destroy(&sem)
1944 #endif
1945
1946 class Semaphore : public StackObj {
1947 public:
1948 Semaphore();
1949 ~Semaphore();
1950 void signal();
1951 void wait();
1952 bool trywait();
1953 bool timedwait(unsigned int sec, int nsec);
1954 private:
1955 jlong currenttime() const;
1956 os_semaphore_t _semaphore;
1957 };
1958
1959 Semaphore::Semaphore() : _semaphore(0) {
1960 SEM_INIT(_semaphore, 0);
1961 }
1962
1963 Semaphore::~Semaphore() {
1964 SEM_DESTROY(_semaphore);
1965 }
1966
1967 void Semaphore::signal() {
1968 SEM_POST(_semaphore);
1969 }
1970
1971 void Semaphore::wait() {
1972 SEM_WAIT(_semaphore);
1973 }
1974
1975 jlong Semaphore::currenttime() const {
1976 struct timeval tv;
1977 gettimeofday(&tv, NULL);
1978 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1979 }
1980
1981 #ifdef __APPLE__
1982 bool Semaphore::trywait() {
1983 return timedwait(0, 0);
1984 }
1985
1986 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1987 kern_return_t kr = KERN_ABORTED;
1988 mach_timespec_t waitspec;
1989 waitspec.tv_sec = sec;
1990 waitspec.tv_nsec = nsec;
1991
1992 jlong starttime = currenttime();
1993
1994 kr = semaphore_timedwait(_semaphore, waitspec);
1995 while (kr == KERN_ABORTED) {
1996 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1997
1998 jlong current = currenttime();
1999 jlong passedtime = current - starttime;
2000
2001 if (passedtime >= totalwait) {
2002 waitspec.tv_sec = 0;
2003 waitspec.tv_nsec = 0;
2004 } else {
2005 jlong waittime = totalwait - (current - starttime);
2006 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2007 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2008 }
2009
2010 kr = semaphore_timedwait(_semaphore, waitspec);
2011 }
2012
2013 return kr == KERN_SUCCESS;
2014 }
2015
2016 #else
2017
2018 bool Semaphore::trywait() {
2019 return sem_trywait(&_semaphore) == 0;
2020 }
2021
2022 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2023 struct timespec ts;
2024 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2025
2026 while (1) {
2027 int result = sem_timedwait(&_semaphore, &ts);
2028 if (result == 0) {
2029 return true;
2030 } else if (errno == EINTR) {
2031 continue;
2032 } else if (errno == ETIMEDOUT) {
2033 return false;
2034 } else {
2035 return false;
2036 }
2037 }
2038 }
2039
2040 #endif // __APPLE__
2041
2042 static os_semaphore_t sig_sem;
2043 static Semaphore sr_semaphore;
2044
2045 void os::signal_init_pd() {
2046 // Initialize signal structures
2047 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2048
2049 // Initialize signal semaphore
2050 ::SEM_INIT(sig_sem, 0);
2051 }
2052
2053 void os::signal_notify(int sig) {
2054 Atomic::inc(&pending_signals[sig]);
2055 ::SEM_POST(sig_sem);
2056 }
2057
2058 static int check_pending_signals(bool wait) {
2059 Atomic::store(0, &sigint_count);
2060 for (;;) {
2061 for (int i = 0; i < NSIG + 1; i++) {
2062 jint n = pending_signals[i];
2063 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2064 return i;
2065 }
2066 }
2067 if (!wait) {
2068 return -1;
2069 }
2070 JavaThread *thread = JavaThread::current();
2071 ThreadBlockInVM tbivm(thread);
2072
2073 bool threadIsSuspended;
2074 do {
2075 thread->set_suspend_equivalent();
2076 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2077 ::SEM_WAIT(sig_sem);
2078
2079 // were we externally suspended while we were waiting?
2080 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2081 if (threadIsSuspended) {
2082 //
2083 // The semaphore has been incremented, but while we were waiting
2084 // another thread suspended us. We don't want to continue running
2085 // while suspended because that would surprise the thread that
2086 // suspended us.
2087 //
2088 ::SEM_POST(sig_sem);
2089
2090 thread->java_suspend_self();
2091 }
2092 } while (threadIsSuspended);
2093 }
2094 }
2095
2096 int os::signal_lookup() {
2097 return check_pending_signals(false);
2098 }
2099
2100 int os::signal_wait() {
2101 return check_pending_signals(true);
2102 }
2103
2104 ////////////////////////////////////////////////////////////////////////////////
2105 // Virtual Memory
2106
2107 int os::vm_page_size() {
2108 // Seems redundant as all get out
2109 assert(os::Bsd::page_size() != -1, "must call os::init");
2110 return os::Bsd::page_size();
2111 }
2112
2113 // Solaris allocates memory by pages.
2114 int os::vm_allocation_granularity() {
2115 assert(os::Bsd::page_size() != -1, "must call os::init");
2116 return os::Bsd::page_size();
2117 }
2118
2119 // Rationale behind this function:
2120 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2121 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2122 // samples for JITted code. Here we create private executable mapping over the code cache
2123 // and then we can use standard (well, almost, as mapping can change) way to provide
2124 // info for the reporting script by storing timestamp and location of symbol
2125 void bsd_wrap_code(char* base, size_t size) {
2126 static volatile jint cnt = 0;
2127
2128 if (!UseOprofile) {
2129 return;
2130 }
2131
2132 char buf[PATH_MAX + 1];
2133 int num = Atomic::add(1, &cnt);
2134
2135 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2136 os::get_temp_directory(), os::current_process_id(), num);
2137 unlink(buf);
2138
2139 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2140
2141 if (fd != -1) {
2142 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2143 if (rv != (off_t)-1) {
2144 if (::write(fd, "", 1) == 1) {
2145 mmap(base, size,
2146 PROT_READ|PROT_WRITE|PROT_EXEC,
2147 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2148 }
2149 }
2150 ::close(fd);
2151 unlink(buf);
2152 }
2153 }
2154
2155 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2156 int err) {
2157 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2158 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2159 strerror(err), err);
2160 }
2161
2162 // NOTE: Bsd kernel does not really reserve the pages for us.
2163 // All it does is to check if there are enough free pages
2164 // left at the time of mmap(). This could be a potential
2165 // problem.
2166 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2167 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2168 #ifdef __OpenBSD__
2169 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2170 if (::mprotect(addr, size, prot) == 0) {
2171 return true;
2172 }
2173 #else
2174 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2175 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2176 if (res != (uintptr_t) MAP_FAILED) {
2177 return true;
2178 }
2179 #endif
2180
2181 // Warn about any commit errors we see in non-product builds just
2182 // in case mmap() doesn't work as described on the man page.
2183 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2184
2185 return false;
2186 }
2187
2188 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2189 bool exec) {
2190 // alignment_hint is ignored on this OS
2191 return pd_commit_memory(addr, size, exec);
2192 }
2193
2194 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2195 const char* mesg) {
2196 assert(mesg != NULL, "mesg must be specified");
2197 if (!pd_commit_memory(addr, size, exec)) {
2198 // add extra info in product mode for vm_exit_out_of_memory():
2199 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2200 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2201 }
2202 }
2203
2204 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2205 size_t alignment_hint, bool exec,
2206 const char* mesg) {
2207 // alignment_hint is ignored on this OS
2208 pd_commit_memory_or_exit(addr, size, exec, mesg);
2209 }
2210
2211 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2212 }
2213
2214 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2215 ::madvise(addr, bytes, MADV_DONTNEED);
2216 }
2217
2218 void os::numa_make_global(char *addr, size_t bytes) {
2219 }
2220
2221 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2222 }
2223
2224 bool os::numa_topology_changed() { return false; }
2225
2226 size_t os::numa_get_groups_num() {
2227 return 1;
2228 }
2229
2230 int os::numa_get_group_id() {
2231 return 0;
2232 }
2233
2234 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2235 if (size > 0) {
2236 ids[0] = 0;
2237 return 1;
2238 }
2239 return 0;
2240 }
2241
2242 bool os::get_page_info(char *start, page_info* info) {
2243 return false;
2244 }
2245
2246 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2247 return end;
2248 }
2249
2250
2251 bool os::pd_uncommit_memory(char* addr, size_t size) {
2252 #ifdef __OpenBSD__
2253 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2254 return ::mprotect(addr, size, PROT_NONE) == 0;
2255 #else
2256 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2257 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2258 return res != (uintptr_t) MAP_FAILED;
2259 #endif
2260 }
2261
2262 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2263 return os::commit_memory(addr, size, !ExecMem);
2264 }
2265
2266 // If this is a growable mapping, remove the guard pages entirely by
2267 // munmap()ping them. If not, just call uncommit_memory().
2268 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2269 return os::uncommit_memory(addr, size);
2270 }
2271
2272 static address _highest_vm_reserved_address = NULL;
2273
2274 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2275 // at 'requested_addr'. If there are existing memory mappings at the same
2276 // location, however, they will be overwritten. If 'fixed' is false,
2277 // 'requested_addr' is only treated as a hint, the return value may or
2278 // may not start from the requested address. Unlike Bsd mmap(), this
2279 // function returns NULL to indicate failure.
2280 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2281 char * addr;
2282 int flags;
2283
2284 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2285 if (fixed) {
2286 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2287 flags |= MAP_FIXED;
2288 }
2289
2290 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2291 // touch an uncommitted page. Otherwise, the read/write might
2292 // succeed if we have enough swap space to back the physical page.
2293 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2294 flags, -1, 0);
2295
2296 if (addr != MAP_FAILED) {
2297 // anon_mmap() should only get called during VM initialization,
2298 // don't need lock (actually we can skip locking even it can be called
2299 // from multiple threads, because _highest_vm_reserved_address is just a
2300 // hint about the upper limit of non-stack memory regions.)
2301 if ((address)addr + bytes > _highest_vm_reserved_address) {
2302 _highest_vm_reserved_address = (address)addr + bytes;
2303 }
2304 }
2305
2306 return addr == MAP_FAILED ? NULL : addr;
2307 }
2308
2309 // Don't update _highest_vm_reserved_address, because there might be memory
2310 // regions above addr + size. If so, releasing a memory region only creates
2311 // a hole in the address space, it doesn't help prevent heap-stack collision.
2312 //
2313 static int anon_munmap(char * addr, size_t size) {
2314 return ::munmap(addr, size) == 0;
2315 }
2316
2317 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2318 size_t alignment_hint) {
2319 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2320 }
2321
2322 bool os::pd_release_memory(char* addr, size_t size) {
2323 return anon_munmap(addr, size);
2324 }
2325
2326 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2327 // Bsd wants the mprotect address argument to be page aligned.
2328 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2329
2330 // According to SUSv3, mprotect() should only be used with mappings
2331 // established by mmap(), and mmap() always maps whole pages. Unaligned
2332 // 'addr' likely indicates problem in the VM (e.g. trying to change
2333 // protection of malloc'ed or statically allocated memory). Check the
2334 // caller if you hit this assert.
2335 assert(addr == bottom, "sanity check");
2336
2337 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2338 return ::mprotect(bottom, size, prot) == 0;
2339 }
2340
2341 // Set protections specified
2342 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2343 bool is_committed) {
2344 unsigned int p = 0;
2345 switch (prot) {
2346 case MEM_PROT_NONE: p = PROT_NONE; break;
2347 case MEM_PROT_READ: p = PROT_READ; break;
2348 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2349 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2350 default:
2351 ShouldNotReachHere();
2352 }
2353 // is_committed is unused.
2354 return bsd_mprotect(addr, bytes, p);
2355 }
2356
2357 bool os::guard_memory(char* addr, size_t size) {
2358 return bsd_mprotect(addr, size, PROT_NONE);
2359 }
2360
2361 bool os::unguard_memory(char* addr, size_t size) {
2362 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2363 }
2364
2365 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2366 return false;
2367 }
2368
2369 // Large page support
2370
2371 static size_t _large_page_size = 0;
2372
2373 void os::large_page_init() {
2374 }
2375
2376
2377 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2378 fatal("This code is not used or maintained.");
2379
2380 // "exec" is passed in but not used. Creating the shared image for
2381 // the code cache doesn't have an SHM_X executable permission to check.
2382 assert(UseLargePages && UseSHM, "only for SHM large pages");
2383
2384 key_t key = IPC_PRIVATE;
2385 char *addr;
2386
2387 bool warn_on_failure = UseLargePages &&
2388 (!FLAG_IS_DEFAULT(UseLargePages) ||
2389 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2390 );
2391 char msg[128];
2392
2393 // Create a large shared memory region to attach to based on size.
2394 // Currently, size is the total size of the heap
2395 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2396 if (shmid == -1) {
2397 // Possible reasons for shmget failure:
2398 // 1. shmmax is too small for Java heap.
2399 // > check shmmax value: cat /proc/sys/kernel/shmmax
2400 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2401 // 2. not enough large page memory.
2402 // > check available large pages: cat /proc/meminfo
2403 // > increase amount of large pages:
2404 // echo new_value > /proc/sys/vm/nr_hugepages
2405 // Note 1: different Bsd may use different name for this property,
2406 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2407 // Note 2: it's possible there's enough physical memory available but
2408 // they are so fragmented after a long run that they can't
2409 // coalesce into large pages. Try to reserve large pages when
2410 // the system is still "fresh".
2411 if (warn_on_failure) {
2412 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2413 warning(msg);
2414 }
2415 return NULL;
2416 }
2417
2418 // attach to the region
2419 addr = (char*)shmat(shmid, req_addr, 0);
2420 int err = errno;
2421
2422 // Remove shmid. If shmat() is successful, the actual shared memory segment
2423 // will be deleted when it's detached by shmdt() or when the process
2424 // terminates. If shmat() is not successful this will remove the shared
2425 // segment immediately.
2426 shmctl(shmid, IPC_RMID, NULL);
2427
2428 if ((intptr_t)addr == -1) {
2429 if (warn_on_failure) {
2430 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2431 warning(msg);
2432 }
2433 return NULL;
2434 }
2435
2436 // The memory is committed
2437 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2438
2439 return addr;
2440 }
2441
2442 bool os::release_memory_special(char* base, size_t bytes) {
2443 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2444 // detaching the SHM segment will also delete it, see reserve_memory_special()
2445 int rslt = shmdt(base);
2446 if (rslt == 0) {
2447 tkr.record((address)base, bytes);
2448 return true;
2449 } else {
2450 tkr.discard();
2451 return false;
2452 }
2453
2454 }
2455
2456 size_t os::large_page_size() {
2457 return _large_page_size;
2458 }
2459
2460 // HugeTLBFS allows application to commit large page memory on demand;
2461 // with SysV SHM the entire memory region must be allocated as shared
2462 // memory.
2463 bool os::can_commit_large_page_memory() {
2464 return UseHugeTLBFS;
2465 }
2466
2467 bool os::can_execute_large_page_memory() {
2468 return UseHugeTLBFS;
2469 }
2470
2471 // Reserve memory at an arbitrary address, only if that area is
2472 // available (and not reserved for something else).
2473
2474 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2475 const int max_tries = 10;
2476 char* base[max_tries];
2477 size_t size[max_tries];
2478 const size_t gap = 0x000000;
2479
2480 // Assert only that the size is a multiple of the page size, since
2481 // that's all that mmap requires, and since that's all we really know
2482 // about at this low abstraction level. If we need higher alignment,
2483 // we can either pass an alignment to this method or verify alignment
2484 // in one of the methods further up the call chain. See bug 5044738.
2485 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2486
2487 // Repeatedly allocate blocks until the block is allocated at the
2488 // right spot. Give up after max_tries. Note that reserve_memory() will
2489 // automatically update _highest_vm_reserved_address if the call is
2490 // successful. The variable tracks the highest memory address every reserved
2491 // by JVM. It is used to detect heap-stack collision if running with
2492 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2493 // space than needed, it could confuse the collision detecting code. To
2494 // solve the problem, save current _highest_vm_reserved_address and
2495 // calculate the correct value before return.
2496 address old_highest = _highest_vm_reserved_address;
2497
2498 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2499 // if kernel honors the hint then we can return immediately.
2500 char * addr = anon_mmap(requested_addr, bytes, false);
2501 if (addr == requested_addr) {
2502 return requested_addr;
2503 }
2504
2505 if (addr != NULL) {
2506 // mmap() is successful but it fails to reserve at the requested address
2507 anon_munmap(addr, bytes);
2508 }
2509
2510 int i;
2511 for (i = 0; i < max_tries; ++i) {
2512 base[i] = reserve_memory(bytes);
2513
2514 if (base[i] != NULL) {
2515 // Is this the block we wanted?
2516 if (base[i] == requested_addr) {
2517 size[i] = bytes;
2518 break;
2519 }
2520
2521 // Does this overlap the block we wanted? Give back the overlapped
2522 // parts and try again.
2523
2524 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2525 if (top_overlap >= 0 && top_overlap < bytes) {
2526 unmap_memory(base[i], top_overlap);
2527 base[i] += top_overlap;
2528 size[i] = bytes - top_overlap;
2529 } else {
2530 size_t bottom_overlap = base[i] + bytes - requested_addr;
2531 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2532 unmap_memory(requested_addr, bottom_overlap);
2533 size[i] = bytes - bottom_overlap;
2534 } else {
2535 size[i] = bytes;
2536 }
2537 }
2538 }
2539 }
2540
2541 // Give back the unused reserved pieces.
2542
2543 for (int j = 0; j < i; ++j) {
2544 if (base[j] != NULL) {
2545 unmap_memory(base[j], size[j]);
2546 }
2547 }
2548
2549 if (i < max_tries) {
2550 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2551 return requested_addr;
2552 } else {
2553 _highest_vm_reserved_address = old_highest;
2554 return NULL;
2555 }
2556 }
2557
2558 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2559 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2560 }
2561
2562 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2563 // Solaris uses poll(), bsd uses park().
2564 // Poll() is likely a better choice, assuming that Thread.interrupt()
2565 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2566 // SIGSEGV, see 4355769.
2567
2568 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2569 assert(thread == Thread::current(), "thread consistency check");
2570
2571 ParkEvent * const slp = thread->_SleepEvent ;
2572 slp->reset() ;
2573 OrderAccess::fence() ;
2574
2575 if (interruptible) {
2576 jlong prevtime = javaTimeNanos();
2577
2578 for (;;) {
2579 if (os::is_interrupted(thread, true)) {
2580 return OS_INTRPT;
2581 }
2582
2583 jlong newtime = javaTimeNanos();
2584
2585 if (newtime - prevtime < 0) {
2586 // time moving backwards, should only happen if no monotonic clock
2587 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2588 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2589 } else {
2590 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2591 }
2592
2593 if(millis <= 0) {
2594 return OS_OK;
2595 }
2596
2597 prevtime = newtime;
2598
2599 {
2600 assert(thread->is_Java_thread(), "sanity check");
2601 JavaThread *jt = (JavaThread *) thread;
2602 ThreadBlockInVM tbivm(jt);
2603 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2604
2605 jt->set_suspend_equivalent();
2606 // cleared by handle_special_suspend_equivalent_condition() or
2607 // java_suspend_self() via check_and_wait_while_suspended()
2608
2609 slp->park(millis);
2610
2611 // were we externally suspended while we were waiting?
2612 jt->check_and_wait_while_suspended();
2613 }
2614 }
2615 } else {
2616 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2617 jlong prevtime = javaTimeNanos();
2618
2619 for (;;) {
2620 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2621 // the 1st iteration ...
2622 jlong newtime = javaTimeNanos();
2623
2624 if (newtime - prevtime < 0) {
2625 // time moving backwards, should only happen if no monotonic clock
2626 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2627 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2628 } else {
2629 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2630 }
2631
2632 if(millis <= 0) break ;
2633
2634 prevtime = newtime;
2635 slp->park(millis);
2636 }
2637 return OS_OK ;
2638 }
2639 }
2640
2641 void os::naked_short_sleep(jlong ms) {
2642 struct timespec req;
2643
2644 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2645 req.tv_sec = 0;
2646 if (ms > 0) {
2647 req.tv_nsec = (ms % 1000) * 1000000;
2648 }
2649 else {
2650 req.tv_nsec = 1;
2651 }
2652
2653 nanosleep(&req, NULL);
2654
2655 return;
2656 }
2657
2658 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2659 void os::infinite_sleep() {
2660 while (true) { // sleep forever ...
2661 ::sleep(100); // ... 100 seconds at a time
2662 }
2663 }
2664
2665 // Used to convert frequent JVM_Yield() to nops
2666 bool os::dont_yield() {
2667 return DontYieldALot;
2668 }
2669
2670 void os::yield() {
2671 sched_yield();
2672 }
2673
2674 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2675
2676 void os::yield_all(int attempts) {
2677 // Yields to all threads, including threads with lower priorities
2678 // Threads on Bsd are all with same priority. The Solaris style
2679 // os::yield_all() with nanosleep(1ms) is not necessary.
2680 sched_yield();
2681 }
2682
2683 // Called from the tight loops to possibly influence time-sharing heuristics
2684 void os::loop_breaker(int attempts) {
2685 os::yield_all(attempts);
2686 }
2687
2688 ////////////////////////////////////////////////////////////////////////////////
2689 // thread priority support
2690
2691 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2692 // only supports dynamic priority, static priority must be zero. For real-time
2693 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2694 // However, for large multi-threaded applications, SCHED_RR is not only slower
2695 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2696 // of 5 runs - Sep 2005).
2697 //
2698 // The following code actually changes the niceness of kernel-thread/LWP. It
2699 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2700 // not the entire user process, and user level threads are 1:1 mapped to kernel
2701 // threads. It has always been the case, but could change in the future. For
2702 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2703 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2704
2705 #if !defined(__APPLE__)
2706 int os::java_to_os_priority[CriticalPriority + 1] = {
2707 19, // 0 Entry should never be used
2708
2709 0, // 1 MinPriority
2710 3, // 2
2711 6, // 3
2712
2713 10, // 4
2714 15, // 5 NormPriority
2715 18, // 6
2716
2717 21, // 7
2718 25, // 8
2719 28, // 9 NearMaxPriority
2720
2721 31, // 10 MaxPriority
2722
2723 31 // 11 CriticalPriority
2724 };
2725 #else
2726 /* Using Mach high-level priority assignments */
2727 int os::java_to_os_priority[CriticalPriority + 1] = {
2728 0, // 0 Entry should never be used (MINPRI_USER)
2729
2730 27, // 1 MinPriority
2731 28, // 2
2732 29, // 3
2733
2734 30, // 4
2735 31, // 5 NormPriority (BASEPRI_DEFAULT)
2736 32, // 6
2737
2738 33, // 7
2739 34, // 8
2740 35, // 9 NearMaxPriority
2741
2742 36, // 10 MaxPriority
2743
2744 36 // 11 CriticalPriority
2745 };
2746 #endif
2747
2748 static int prio_init() {
2749 if (ThreadPriorityPolicy == 1) {
2750 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2751 // if effective uid is not root. Perhaps, a more elegant way of doing
2752 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2753 if (geteuid() != 0) {
2754 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2755 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2756 }
2757 ThreadPriorityPolicy = 0;
2758 }
2759 }
2760 if (UseCriticalJavaThreadPriority) {
2761 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2762 }
2763 return 0;
2764 }
2765
2766 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2767 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2768
2769 #ifdef __OpenBSD__
2770 // OpenBSD pthread_setprio starves low priority threads
2771 return OS_OK;
2772 #elif defined(__FreeBSD__)
2773 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2774 #elif defined(__APPLE__) || defined(__NetBSD__)
2775 struct sched_param sp;
2776 int policy;
2777 pthread_t self = pthread_self();
2778
2779 if (pthread_getschedparam(self, &policy, &sp) != 0)
2780 return OS_ERR;
2781
2782 sp.sched_priority = newpri;
2783 if (pthread_setschedparam(self, policy, &sp) != 0)
2784 return OS_ERR;
2785
2786 return OS_OK;
2787 #else
2788 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2789 return (ret == 0) ? OS_OK : OS_ERR;
2790 #endif
2791 }
2792
2793 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2794 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2795 *priority_ptr = java_to_os_priority[NormPriority];
2796 return OS_OK;
2797 }
2798
2799 errno = 0;
2800 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2801 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2802 #elif defined(__APPLE__) || defined(__NetBSD__)
2803 int policy;
2804 struct sched_param sp;
2805
2806 pthread_getschedparam(pthread_self(), &policy, &sp);
2807 *priority_ptr = sp.sched_priority;
2808 #else
2809 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2810 #endif
2811 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2812 }
2813
2814 // Hint to the underlying OS that a task switch would not be good.
2815 // Void return because it's a hint and can fail.
2816 void os::hint_no_preempt() {}
2817
2818 ////////////////////////////////////////////////////////////////////////////////
2819 // suspend/resume support
2820
2821 // the low-level signal-based suspend/resume support is a remnant from the
2822 // old VM-suspension that used to be for java-suspension, safepoints etc,
2823 // within hotspot. Now there is a single use-case for this:
2824 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2825 // that runs in the watcher thread.
2826 // The remaining code is greatly simplified from the more general suspension
2827 // code that used to be used.
2828 //
2829 // The protocol is quite simple:
2830 // - suspend:
2831 // - sends a signal to the target thread
2832 // - polls the suspend state of the osthread using a yield loop
2833 // - target thread signal handler (SR_handler) sets suspend state
2834 // and blocks in sigsuspend until continued
2835 // - resume:
2836 // - sets target osthread state to continue
2837 // - sends signal to end the sigsuspend loop in the SR_handler
2838 //
2839 // Note that the SR_lock plays no role in this suspend/resume protocol.
2840 //
2841
2842 static void resume_clear_context(OSThread *osthread) {
2843 osthread->set_ucontext(NULL);
2844 osthread->set_siginfo(NULL);
2845 }
2846
2847 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2848 osthread->set_ucontext(context);
2849 osthread->set_siginfo(siginfo);
2850 }
2851
2852 //
2853 // Handler function invoked when a thread's execution is suspended or
2854 // resumed. We have to be careful that only async-safe functions are
2855 // called here (Note: most pthread functions are not async safe and
2856 // should be avoided.)
2857 //
2858 // Note: sigwait() is a more natural fit than sigsuspend() from an
2859 // interface point of view, but sigwait() prevents the signal hander
2860 // from being run. libpthread would get very confused by not having
2861 // its signal handlers run and prevents sigwait()'s use with the
2862 // mutex granting granting signal.
2863 //
2864 // Currently only ever called on the VMThread or JavaThread
2865 //
2866 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2867 // Save and restore errno to avoid confusing native code with EINTR
2868 // after sigsuspend.
2869 int old_errno = errno;
2870
2871 Thread* thread = Thread::current();
2872 OSThread* osthread = thread->osthread();
2873 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2874
2875 os::SuspendResume::State current = osthread->sr.state();
2876 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2877 suspend_save_context(osthread, siginfo, context);
2878
2879 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2880 os::SuspendResume::State state = osthread->sr.suspended();
2881 if (state == os::SuspendResume::SR_SUSPENDED) {
2882 sigset_t suspend_set; // signals for sigsuspend()
2883
2884 // get current set of blocked signals and unblock resume signal
2885 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2886 sigdelset(&suspend_set, SR_signum);
2887
2888 sr_semaphore.signal();
2889 // wait here until we are resumed
2890 while (1) {
2891 sigsuspend(&suspend_set);
2892
2893 os::SuspendResume::State result = osthread->sr.running();
2894 if (result == os::SuspendResume::SR_RUNNING) {
2895 sr_semaphore.signal();
2896 break;
2897 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2898 ShouldNotReachHere();
2899 }
2900 }
2901
2902 } else if (state == os::SuspendResume::SR_RUNNING) {
2903 // request was cancelled, continue
2904 } else {
2905 ShouldNotReachHere();
2906 }
2907
2908 resume_clear_context(osthread);
2909 } else if (current == os::SuspendResume::SR_RUNNING) {
2910 // request was cancelled, continue
2911 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2912 // ignore
2913 } else {
2914 // ignore
2915 }
2916
2917 errno = old_errno;
2918 }
2919
2920
2921 static int SR_initialize() {
2922 struct sigaction act;
2923 char *s;
2924 /* Get signal number to use for suspend/resume */
2925 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2926 int sig = ::strtol(s, 0, 10);
2927 if (sig > 0 || sig < NSIG) {
2928 SR_signum = sig;
2929 }
2930 }
2931
2932 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2933 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2934
2935 sigemptyset(&SR_sigset);
2936 sigaddset(&SR_sigset, SR_signum);
2937
2938 /* Set up signal handler for suspend/resume */
2939 act.sa_flags = SA_RESTART|SA_SIGINFO;
2940 act.sa_handler = (void (*)(int)) SR_handler;
2941
2942 // SR_signum is blocked by default.
2943 // 4528190 - We also need to block pthread restart signal (32 on all
2944 // supported Bsd platforms). Note that BsdThreads need to block
2945 // this signal for all threads to work properly. So we don't have
2946 // to use hard-coded signal number when setting up the mask.
2947 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2948
2949 if (sigaction(SR_signum, &act, 0) == -1) {
2950 return -1;
2951 }
2952
2953 // Save signal flag
2954 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2955 return 0;
2956 }
2957
2958 static int sr_notify(OSThread* osthread) {
2959 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2960 assert_status(status == 0, status, "pthread_kill");
2961 return status;
2962 }
2963
2964 // "Randomly" selected value for how long we want to spin
2965 // before bailing out on suspending a thread, also how often
2966 // we send a signal to a thread we want to resume
2967 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2968 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2969
2970 // returns true on success and false on error - really an error is fatal
2971 // but this seems the normal response to library errors
2972 static bool do_suspend(OSThread* osthread) {
2973 assert(osthread->sr.is_running(), "thread should be running");
2974 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2975
2976 // mark as suspended and send signal
2977 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2978 // failed to switch, state wasn't running?
2979 ShouldNotReachHere();
2980 return false;
2981 }
2982
2983 if (sr_notify(osthread) != 0) {
2984 ShouldNotReachHere();
2985 }
2986
2987 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2988 while (true) {
2989 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2990 break;
2991 } else {
2992 // timeout
2993 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2994 if (cancelled == os::SuspendResume::SR_RUNNING) {
2995 return false;
2996 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2997 // make sure that we consume the signal on the semaphore as well
2998 sr_semaphore.wait();
2999 break;
3000 } else {
3001 ShouldNotReachHere();
3002 return false;
3003 }
3004 }
3005 }
3006
3007 guarantee(osthread->sr.is_suspended(), "Must be suspended");
3008 return true;
3009 }
3010
3011 static void do_resume(OSThread* osthread) {
3012 assert(osthread->sr.is_suspended(), "thread should be suspended");
3013 assert(!sr_semaphore.trywait(), "invalid semaphore state");
3014
3015 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
3016 // failed to switch to WAKEUP_REQUEST
3017 ShouldNotReachHere();
3018 return;
3019 }
3020
3021 while (true) {
3022 if (sr_notify(osthread) == 0) {
3023 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3024 if (osthread->sr.is_running()) {
3025 return;
3026 }
3027 }
3028 } else {
3029 ShouldNotReachHere();
3030 }
3031 }
3032
3033 guarantee(osthread->sr.is_running(), "Must be running!");
3034 }
3035
3036 ////////////////////////////////////////////////////////////////////////////////
3037 // interrupt support
3038
3039 void os::interrupt(Thread* thread) {
3040 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3041 "possibility of dangling Thread pointer");
3042
3043 OSThread* osthread = thread->osthread();
3044
3045 if (!osthread->interrupted()) {
3046 osthread->set_interrupted(true);
3047 // More than one thread can get here with the same value of osthread,
3048 // resulting in multiple notifications. We do, however, want the store
3049 // to interrupted() to be visible to other threads before we execute unpark().
3050 OrderAccess::fence();
3051 ParkEvent * const slp = thread->_SleepEvent ;
3052 if (slp != NULL) slp->unpark() ;
3053 }
3054
3055 // For JSR166. Unpark even if interrupt status already was set
3056 if (thread->is_Java_thread())
3057 ((JavaThread*)thread)->parker()->unpark();
3058
3059 ParkEvent * ev = thread->_ParkEvent ;
3060 if (ev != NULL) ev->unpark() ;
3061
3062 }
3063
3064 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3065 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3066 "possibility of dangling Thread pointer");
3067
3068 OSThread* osthread = thread->osthread();
3069
3070 bool interrupted = osthread->interrupted();
3071
3072 if (interrupted && clear_interrupted) {
3073 osthread->set_interrupted(false);
3074 // consider thread->_SleepEvent->reset() ... optional optimization
3075 }
3076
3077 return interrupted;
3078 }
3079
3080 ///////////////////////////////////////////////////////////////////////////////////
3081 // signal handling (except suspend/resume)
3082
3083 // This routine may be used by user applications as a "hook" to catch signals.
3084 // The user-defined signal handler must pass unrecognized signals to this
3085 // routine, and if it returns true (non-zero), then the signal handler must
3086 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3087 // routine will never retun false (zero), but instead will execute a VM panic
3088 // routine kill the process.
3089 //
3090 // If this routine returns false, it is OK to call it again. This allows
3091 // the user-defined signal handler to perform checks either before or after
3092 // the VM performs its own checks. Naturally, the user code would be making
3093 // a serious error if it tried to handle an exception (such as a null check
3094 // or breakpoint) that the VM was generating for its own correct operation.
3095 //
3096 // This routine may recognize any of the following kinds of signals:
3097 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3098 // It should be consulted by handlers for any of those signals.
3099 //
3100 // The caller of this routine must pass in the three arguments supplied
3101 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3102 // field of the structure passed to sigaction(). This routine assumes that
3103 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3104 //
3105 // Note that the VM will print warnings if it detects conflicting signal
3106 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3107 //
3108 extern "C" JNIEXPORT int
3109 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3110 void* ucontext, int abort_if_unrecognized);
3111
3112 void signalHandler(int sig, siginfo_t* info, void* uc) {
3113 assert(info != NULL && uc != NULL, "it must be old kernel");
3114 int orig_errno = errno; // Preserve errno value over signal handler.
3115 JVM_handle_bsd_signal(sig, info, uc, true);
3116 errno = orig_errno;
3117 }
3118
3119
3120 // This boolean allows users to forward their own non-matching signals
3121 // to JVM_handle_bsd_signal, harmlessly.
3122 bool os::Bsd::signal_handlers_are_installed = false;
3123
3124 // For signal-chaining
3125 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3126 unsigned int os::Bsd::sigs = 0;
3127 bool os::Bsd::libjsig_is_loaded = false;
3128 typedef struct sigaction *(*get_signal_t)(int);
3129 get_signal_t os::Bsd::get_signal_action = NULL;
3130
3131 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3132 struct sigaction *actp = NULL;
3133
3134 if (libjsig_is_loaded) {
3135 // Retrieve the old signal handler from libjsig
3136 actp = (*get_signal_action)(sig);
3137 }
3138 if (actp == NULL) {
3139 // Retrieve the preinstalled signal handler from jvm
3140 actp = get_preinstalled_handler(sig);
3141 }
3142
3143 return actp;
3144 }
3145
3146 static bool call_chained_handler(struct sigaction *actp, int sig,
3147 siginfo_t *siginfo, void *context) {
3148 // Call the old signal handler
3149 if (actp->sa_handler == SIG_DFL) {
3150 // It's more reasonable to let jvm treat it as an unexpected exception
3151 // instead of taking the default action.
3152 return false;
3153 } else if (actp->sa_handler != SIG_IGN) {
3154 if ((actp->sa_flags & SA_NODEFER) == 0) {
3155 // automaticlly block the signal
3156 sigaddset(&(actp->sa_mask), sig);
3157 }
3158
3159 sa_handler_t hand;
3160 sa_sigaction_t sa;
3161 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3162 // retrieve the chained handler
3163 if (siginfo_flag_set) {
3164 sa = actp->sa_sigaction;
3165 } else {
3166 hand = actp->sa_handler;
3167 }
3168
3169 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3170 actp->sa_handler = SIG_DFL;
3171 }
3172
3173 // try to honor the signal mask
3174 sigset_t oset;
3175 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3176
3177 // call into the chained handler
3178 if (siginfo_flag_set) {
3179 (*sa)(sig, siginfo, context);
3180 } else {
3181 (*hand)(sig);
3182 }
3183
3184 // restore the signal mask
3185 pthread_sigmask(SIG_SETMASK, &oset, 0);
3186 }
3187 // Tell jvm's signal handler the signal is taken care of.
3188 return true;
3189 }
3190
3191 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3192 bool chained = false;
3193 // signal-chaining
3194 if (UseSignalChaining) {
3195 struct sigaction *actp = get_chained_signal_action(sig);
3196 if (actp != NULL) {
3197 chained = call_chained_handler(actp, sig, siginfo, context);
3198 }
3199 }
3200 return chained;
3201 }
3202
3203 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3204 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3205 return &sigact[sig];
3206 }
3207 return NULL;
3208 }
3209
3210 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3211 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3212 sigact[sig] = oldAct;
3213 sigs |= (unsigned int)1 << sig;
3214 }
3215
3216 // for diagnostic
3217 int os::Bsd::sigflags[MAXSIGNUM];
3218
3219 int os::Bsd::get_our_sigflags(int sig) {
3220 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3221 return sigflags[sig];
3222 }
3223
3224 void os::Bsd::set_our_sigflags(int sig, int flags) {
3225 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3226 sigflags[sig] = flags;
3227 }
3228
3229 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3230 // Check for overwrite.
3231 struct sigaction oldAct;
3232 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3233
3234 void* oldhand = oldAct.sa_sigaction
3235 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3236 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3237 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3238 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3239 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3240 if (AllowUserSignalHandlers || !set_installed) {
3241 // Do not overwrite; user takes responsibility to forward to us.
3242 return;
3243 } else if (UseSignalChaining) {
3244 // save the old handler in jvm
3245 save_preinstalled_handler(sig, oldAct);
3246 // libjsig also interposes the sigaction() call below and saves the
3247 // old sigaction on it own.
3248 } else {
3249 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3250 "%#lx for signal %d.", (long)oldhand, sig));
3251 }
3252 }
3253
3254 struct sigaction sigAct;
3255 sigfillset(&(sigAct.sa_mask));
3256 sigAct.sa_handler = SIG_DFL;
3257 if (!set_installed) {
3258 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3259 } else {
3260 sigAct.sa_sigaction = signalHandler;
3261 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3262 }
3263 #if __APPLE__
3264 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3265 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3266 // if the signal handler declares it will handle it on alternate stack.
3267 // Notice we only declare we will handle it on alt stack, but we are not
3268 // actually going to use real alt stack - this is just a workaround.
3269 // Please see ux_exception.c, method catch_mach_exception_raise for details
3270 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3271 if (sig == SIGSEGV) {
3272 sigAct.sa_flags |= SA_ONSTACK;
3273 }
3274 #endif
3275
3276 // Save flags, which are set by ours
3277 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3278 sigflags[sig] = sigAct.sa_flags;
3279
3280 int ret = sigaction(sig, &sigAct, &oldAct);
3281 assert(ret == 0, "check");
3282
3283 void* oldhand2 = oldAct.sa_sigaction
3284 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3285 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3286 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3287 }
3288
3289 // install signal handlers for signals that HotSpot needs to
3290 // handle in order to support Java-level exception handling.
3291
3292 void os::Bsd::install_signal_handlers() {
3293 if (!signal_handlers_are_installed) {
3294 signal_handlers_are_installed = true;
3295
3296 // signal-chaining
3297 typedef void (*signal_setting_t)();
3298 signal_setting_t begin_signal_setting = NULL;
3299 signal_setting_t end_signal_setting = NULL;
3300 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3301 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3302 if (begin_signal_setting != NULL) {
3303 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3304 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3305 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3306 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3307 libjsig_is_loaded = true;
3308 assert(UseSignalChaining, "should enable signal-chaining");
3309 }
3310 if (libjsig_is_loaded) {
3311 // Tell libjsig jvm is setting signal handlers
3312 (*begin_signal_setting)();
3313 }
3314
3315 set_signal_handler(SIGSEGV, true);
3316 set_signal_handler(SIGPIPE, true);
3317 set_signal_handler(SIGBUS, true);
3318 set_signal_handler(SIGILL, true);
3319 set_signal_handler(SIGFPE, true);
3320 set_signal_handler(SIGXFSZ, true);
3321
3322 #if defined(__APPLE__)
3323 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3324 // signals caught and handled by the JVM. To work around this, we reset the mach task
3325 // signal handler that's placed on our process by CrashReporter. This disables
3326 // CrashReporter-based reporting.
3327 //
3328 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3329 // on caught fatal signals.
3330 //
3331 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3332 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3333 // exception handling, while leaving the standard BSD signal handlers functional.
3334 kern_return_t kr;
3335 kr = task_set_exception_ports(mach_task_self(),
3336 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3337 MACH_PORT_NULL,
3338 EXCEPTION_STATE_IDENTITY,
3339 MACHINE_THREAD_STATE);
3340
3341 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3342 #endif
3343
3344 if (libjsig_is_loaded) {
3345 // Tell libjsig jvm finishes setting signal handlers
3346 (*end_signal_setting)();
3347 }
3348
3349 // We don't activate signal checker if libjsig is in place, we trust ourselves
3350 // and if UserSignalHandler is installed all bets are off
3351 if (CheckJNICalls) {
3352 if (libjsig_is_loaded) {
3353 if (PrintJNIResolving) {
3354 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3355 }
3356 check_signals = false;
3357 }
3358 if (AllowUserSignalHandlers) {
3359 if (PrintJNIResolving) {
3360 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3361 }
3362 check_signals = false;
3363 }
3364 }
3365 }
3366 }
3367
3368
3369 /////
3370 // glibc on Bsd platform uses non-documented flag
3371 // to indicate, that some special sort of signal
3372 // trampoline is used.
3373 // We will never set this flag, and we should
3374 // ignore this flag in our diagnostic
3375 #ifdef SIGNIFICANT_SIGNAL_MASK
3376 #undef SIGNIFICANT_SIGNAL_MASK
3377 #endif
3378 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3379
3380 static const char* get_signal_handler_name(address handler,
3381 char* buf, int buflen) {
3382 int offset;
3383 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3384 if (found) {
3385 // skip directory names
3386 const char *p1, *p2;
3387 p1 = buf;
3388 size_t len = strlen(os::file_separator());
3389 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3390 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3391 } else {
3392 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3393 }
3394 return buf;
3395 }
3396
3397 static void print_signal_handler(outputStream* st, int sig,
3398 char* buf, size_t buflen) {
3399 struct sigaction sa;
3400
3401 sigaction(sig, NULL, &sa);
3402
3403 // See comment for SIGNIFICANT_SIGNAL_MASK define
3404 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3405
3406 st->print("%s: ", os::exception_name(sig, buf, buflen));
3407
3408 address handler = (sa.sa_flags & SA_SIGINFO)
3409 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3410 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3411
3412 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3413 st->print("SIG_DFL");
3414 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3415 st->print("SIG_IGN");
3416 } else {
3417 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3418 }
3419
3420 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3421
3422 address rh = VMError::get_resetted_sighandler(sig);
3423 // May be, handler was resetted by VMError?
3424 if(rh != NULL) {
3425 handler = rh;
3426 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3427 }
3428
3429 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3430
3431 // Check: is it our handler?
3432 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3433 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3434 // It is our signal handler
3435 // check for flags, reset system-used one!
3436 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3437 st->print(
3438 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3439 os::Bsd::get_our_sigflags(sig));
3440 }
3441 }
3442 st->cr();
3443 }
3444
3445
3446 #define DO_SIGNAL_CHECK(sig) \
3447 if (!sigismember(&check_signal_done, sig)) \
3448 os::Bsd::check_signal_handler(sig)
3449
3450 // This method is a periodic task to check for misbehaving JNI applications
3451 // under CheckJNI, we can add any periodic checks here
3452
3453 void os::run_periodic_checks() {
3454
3455 if (check_signals == false) return;
3456
3457 // SEGV and BUS if overridden could potentially prevent
3458 // generation of hs*.log in the event of a crash, debugging
3459 // such a case can be very challenging, so we absolutely
3460 // check the following for a good measure:
3461 DO_SIGNAL_CHECK(SIGSEGV);
3462 DO_SIGNAL_CHECK(SIGILL);
3463 DO_SIGNAL_CHECK(SIGFPE);
3464 DO_SIGNAL_CHECK(SIGBUS);
3465 DO_SIGNAL_CHECK(SIGPIPE);
3466 DO_SIGNAL_CHECK(SIGXFSZ);
3467
3468
3469 // ReduceSignalUsage allows the user to override these handlers
3470 // see comments at the very top and jvm_solaris.h
3471 if (!ReduceSignalUsage) {
3472 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3473 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3474 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3475 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3476 }
3477
3478 DO_SIGNAL_CHECK(SR_signum);
3479 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3480 }
3481
3482 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3483
3484 static os_sigaction_t os_sigaction = NULL;
3485
3486 void os::Bsd::check_signal_handler(int sig) {
3487 char buf[O_BUFLEN];
3488 address jvmHandler = NULL;
3489
3490
3491 struct sigaction act;
3492 if (os_sigaction == NULL) {
3493 // only trust the default sigaction, in case it has been interposed
3494 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3495 if (os_sigaction == NULL) return;
3496 }
3497
3498 os_sigaction(sig, (struct sigaction*)NULL, &act);
3499
3500
3501 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3502
3503 address thisHandler = (act.sa_flags & SA_SIGINFO)
3504 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3505 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3506
3507
3508 switch(sig) {
3509 case SIGSEGV:
3510 case SIGBUS:
3511 case SIGFPE:
3512 case SIGPIPE:
3513 case SIGILL:
3514 case SIGXFSZ:
3515 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3516 break;
3517
3518 case SHUTDOWN1_SIGNAL:
3519 case SHUTDOWN2_SIGNAL:
3520 case SHUTDOWN3_SIGNAL:
3521 case BREAK_SIGNAL:
3522 jvmHandler = (address)user_handler();
3523 break;
3524
3525 case INTERRUPT_SIGNAL:
3526 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3527 break;
3528
3529 default:
3530 if (sig == SR_signum) {
3531 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3532 } else {
3533 return;
3534 }
3535 break;
3536 }
3537
3538 if (thisHandler != jvmHandler) {
3539 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3540 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3541 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3542 // No need to check this sig any longer
3543 sigaddset(&check_signal_done, sig);
3544 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3545 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3546 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3547 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3548 // No need to check this sig any longer
3549 sigaddset(&check_signal_done, sig);
3550 }
3551
3552 // Dump all the signal
3553 if (sigismember(&check_signal_done, sig)) {
3554 print_signal_handlers(tty, buf, O_BUFLEN);
3555 }
3556 }
3557
3558 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3559
3560 extern bool signal_name(int signo, char* buf, size_t len);
3561
3562 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3563 if (0 < exception_code && exception_code <= SIGRTMAX) {
3564 // signal
3565 if (!signal_name(exception_code, buf, size)) {
3566 jio_snprintf(buf, size, "SIG%d", exception_code);
3567 }
3568 return buf;
3569 } else {
3570 return NULL;
3571 }
3572 }
3573
3574 // this is called _before_ the most of global arguments have been parsed
3575 void os::init(void) {
3576 char dummy; /* used to get a guess on initial stack address */
3577 // first_hrtime = gethrtime();
3578
3579 // With BsdThreads the JavaMain thread pid (primordial thread)
3580 // is different than the pid of the java launcher thread.
3581 // So, on Bsd, the launcher thread pid is passed to the VM
3582 // via the sun.java.launcher.pid property.
3583 // Use this property instead of getpid() if it was correctly passed.
3584 // See bug 6351349.
3585 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3586
3587 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3588
3589 clock_tics_per_sec = CLK_TCK;
3590
3591 init_random(1234567);
3592
3593 ThreadCritical::initialize();
3594
3595 Bsd::set_page_size(getpagesize());
3596 if (Bsd::page_size() == -1) {
3597 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3598 strerror(errno)));
3599 }
3600 init_page_sizes((size_t) Bsd::page_size());
3601
3602 Bsd::initialize_system_info();
3603
3604 // main_thread points to the aboriginal thread
3605 Bsd::_main_thread = pthread_self();
3606
3607 Bsd::clock_init();
3608 initial_time_count = javaTimeNanos();
3609
3610 #ifdef __APPLE__
3611 // XXXDARWIN
3612 // Work around the unaligned VM callbacks in hotspot's
3613 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3614 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3615 // alignment when doing symbol lookup. To work around this, we force early
3616 // binding of all symbols now, thus binding when alignment is known-good.
3617 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3618 #endif
3619 }
3620
3621 // To install functions for atexit system call
3622 extern "C" {
3623 static void perfMemory_exit_helper() {
3624 perfMemory_exit();
3625 }
3626 }
3627
3628 // this is called _after_ the global arguments have been parsed
3629 jint os::init_2(void)
3630 {
3631 // Allocate a single page and mark it as readable for safepoint polling
3632 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3633 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3634
3635 os::set_polling_page( polling_page );
3636
3637 #ifndef PRODUCT
3638 if(Verbose && PrintMiscellaneous)
3639 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3640 #endif
3641
3642 if (!UseMembar) {
3643 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3644 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3645 os::set_memory_serialize_page( mem_serialize_page );
3646
3647 #ifndef PRODUCT
3648 if(Verbose && PrintMiscellaneous)
3649 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3650 #endif
3651 }
3652
3653 // initialize suspend/resume support - must do this before signal_sets_init()
3654 if (SR_initialize() != 0) {
3655 perror("SR_initialize failed");
3656 return JNI_ERR;
3657 }
3658
3659 Bsd::signal_sets_init();
3660 Bsd::install_signal_handlers();
3661
3662 // Check minimum allowable stack size for thread creation and to initialize
3663 // the java system classes, including StackOverflowError - depends on page
3664 // size. Add a page for compiler2 recursion in main thread.
3665 // Add in 2*BytesPerWord times page size to account for VM stack during
3666 // class initialization depending on 32 or 64 bit VM.
3667 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3668 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3669 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3670
3671 size_t threadStackSizeInBytes = ThreadStackSize * K;
3672 if (threadStackSizeInBytes != 0 &&
3673 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3674 tty->print_cr("\nThe stack size specified is too small, "
3675 "Specify at least %dk",
3676 os::Bsd::min_stack_allowed/ K);
3677 return JNI_ERR;
3678 }
3679
3680 // Make the stack size a multiple of the page size so that
3681 // the yellow/red zones can be guarded.
3682 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3683 vm_page_size()));
3684
3685 if (MaxFDLimit) {
3686 // set the number of file descriptors to max. print out error
3687 // if getrlimit/setrlimit fails but continue regardless.
3688 struct rlimit nbr_files;
3689 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3690 if (status != 0) {
3691 if (PrintMiscellaneous && (Verbose || WizardMode))
3692 perror("os::init_2 getrlimit failed");
3693 } else {
3694 nbr_files.rlim_cur = nbr_files.rlim_max;
3695
3696 #ifdef __APPLE__
3697 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3698 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3699 // be used instead
3700 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3701 #endif
3702
3703 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3704 if (status != 0) {
3705 if (PrintMiscellaneous && (Verbose || WizardMode))
3706 perror("os::init_2 setrlimit failed");
3707 }
3708 }
3709 }
3710
3711 // at-exit methods are called in the reverse order of their registration.
3712 // atexit functions are called on return from main or as a result of a
3713 // call to exit(3C). There can be only 32 of these functions registered
3714 // and atexit() does not set errno.
3715
3716 if (PerfAllowAtExitRegistration) {
3717 // only register atexit functions if PerfAllowAtExitRegistration is set.
3718 // atexit functions can be delayed until process exit time, which
3719 // can be problematic for embedded VM situations. Embedded VMs should
3720 // call DestroyJavaVM() to assure that VM resources are released.
3721
3722 // note: perfMemory_exit_helper atexit function may be removed in
3723 // the future if the appropriate cleanup code can be added to the
3724 // VM_Exit VMOperation's doit method.
3725 if (atexit(perfMemory_exit_helper) != 0) {
3726 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3727 }
3728 }
3729
3730 // initialize thread priority policy
3731 prio_init();
3732
3733 #ifdef __APPLE__
3734 // dynamically link to objective c gc registration
3735 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3736 if (handleLibObjc != NULL) {
3737 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3738 }
3739 #endif
3740
3741 return JNI_OK;
3742 }
3743
3744 // this is called at the end of vm_initialization
3745 void os::init_3(void) { }
3746
3747 // Mark the polling page as unreadable
3748 void os::make_polling_page_unreadable(void) {
3749 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3750 fatal("Could not disable polling page");
3751 };
3752
3753 // Mark the polling page as readable
3754 void os::make_polling_page_readable(void) {
3755 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3756 fatal("Could not enable polling page");
3757 }
3758 };
3759
3760 int os::active_processor_count() {
3761 return _processor_count;
3762 }
3763
3764 void os::set_native_thread_name(const char *name) {
3765 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3766 // This is only supported in Snow Leopard and beyond
3767 if (name != NULL) {
3768 // Add a "Java: " prefix to the name
3769 char buf[MAXTHREADNAMESIZE];
3770 snprintf(buf, sizeof(buf), "Java: %s", name);
3771 pthread_setname_np(buf);
3772 }
3773 #endif
3774 }
3775
3776 bool os::distribute_processes(uint length, uint* distribution) {
3777 // Not yet implemented.
3778 return false;
3779 }
3780
3781 bool os::bind_to_processor(uint processor_id) {
3782 // Not yet implemented.
3783 return false;
3784 }
3785
3786 void os::SuspendedThreadTask::internal_do_task() {
3787 if (do_suspend(_thread->osthread())) {
3788 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3789 do_task(context);
3790 do_resume(_thread->osthread());
3791 }
3792 }
3793
3794 ///
3795 class PcFetcher : public os::SuspendedThreadTask {
3796 public:
3797 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3798 ExtendedPC result();
3799 protected:
3800 void do_task(const os::SuspendedThreadTaskContext& context);
3801 private:
3802 ExtendedPC _epc;
3803 };
3804
3805 ExtendedPC PcFetcher::result() {
3806 guarantee(is_done(), "task is not done yet.");
3807 return _epc;
3808 }
3809
3810 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3811 Thread* thread = context.thread();
3812 OSThread* osthread = thread->osthread();
3813 if (osthread->ucontext() != NULL) {
3814 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3815 } else {
3816 // NULL context is unexpected, double-check this is the VMThread
3817 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3818 }
3819 }
3820
3821 // Suspends the target using the signal mechanism and then grabs the PC before
3822 // resuming the target. Used by the flat-profiler only
3823 ExtendedPC os::get_thread_pc(Thread* thread) {
3824 // Make sure that it is called by the watcher for the VMThread
3825 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3826 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3827
3828 PcFetcher fetcher(thread);
3829 fetcher.run();
3830 return fetcher.result();
3831 }
3832
3833 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3834 {
3835 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3836 }
3837
3838 ////////////////////////////////////////////////////////////////////////////////
3839 // debug support
3840
3841 bool os::find(address addr, outputStream* st) {
3842 Dl_info dlinfo;
3843 memset(&dlinfo, 0, sizeof(dlinfo));
3844 if (dladdr(addr, &dlinfo) != 0) {
3845 st->print(PTR_FORMAT ": ", addr);
3846 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3847 st->print("%s+%#x", dlinfo.dli_sname,
3848 addr - (intptr_t)dlinfo.dli_saddr);
3849 } else if (dlinfo.dli_fbase != NULL) {
3850 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3851 } else {
3852 st->print("<absolute address>");
3853 }
3854 if (dlinfo.dli_fname != NULL) {
3855 st->print(" in %s", dlinfo.dli_fname);
3856 }
3857 if (dlinfo.dli_fbase != NULL) {
3858 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3859 }
3860 st->cr();
3861
3862 if (Verbose) {
3863 // decode some bytes around the PC
3864 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3865 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3866 address lowest = (address) dlinfo.dli_sname;
3867 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3868 if (begin < lowest) begin = lowest;
3869 Dl_info dlinfo2;
3870 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3871 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3872 end = (address) dlinfo2.dli_saddr;
3873 Disassembler::decode(begin, end, st);
3874 }
3875 return true;
3876 }
3877 return false;
3878 }
3879
3880 ////////////////////////////////////////////////////////////////////////////////
3881 // misc
3882
3883 // This does not do anything on Bsd. This is basically a hook for being
3884 // able to use structured exception handling (thread-local exception filters)
3885 // on, e.g., Win32.
3886 void
3887 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3888 JavaCallArguments* args, Thread* thread) {
3889 f(value, method, args, thread);
3890 }
3891
3892 void os::print_statistics() {
3893 }
3894
3895 int os::message_box(const char* title, const char* message) {
3896 int i;
3897 fdStream err(defaultStream::error_fd());
3898 for (i = 0; i < 78; i++) err.print_raw("=");
3899 err.cr();
3900 err.print_raw_cr(title);
3901 for (i = 0; i < 78; i++) err.print_raw("-");
3902 err.cr();
3903 err.print_raw_cr(message);
3904 for (i = 0; i < 78; i++) err.print_raw("=");
3905 err.cr();
3906
3907 char buf[16];
3908 // Prevent process from exiting upon "read error" without consuming all CPU
3909 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3910
3911 return buf[0] == 'y' || buf[0] == 'Y';
3912 }
3913
3914 int os::stat(const char *path, struct stat *sbuf) {
3915 char pathbuf[MAX_PATH];
3916 if (strlen(path) > MAX_PATH - 1) {
3917 errno = ENAMETOOLONG;
3918 return -1;
3919 }
3920 os::native_path(strcpy(pathbuf, path));
3921 return ::stat(pathbuf, sbuf);
3922 }
3923
3924 bool os::check_heap(bool force) {
3925 return true;
3926 }
3927
3928 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3929 return ::vsnprintf(buf, count, format, args);
3930 }
3931
3932 // Is a (classpath) directory empty?
3933 bool os::dir_is_empty(const char* path) {
3934 DIR *dir = NULL;
3935 struct dirent *ptr;
3936
3937 dir = opendir(path);
3938 if (dir == NULL) return true;
3939
3940 /* Scan the directory */
3941 bool result = true;
3942 char buf[sizeof(struct dirent) + MAX_PATH];
3943 while (result && (ptr = ::readdir(dir)) != NULL) {
3944 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3945 result = false;
3946 }
3947 }
3948 closedir(dir);
3949 return result;
3950 }
3951
3952 // This code originates from JDK's sysOpen and open64_w
3953 // from src/solaris/hpi/src/system_md.c
3954
3955 #ifndef O_DELETE
3956 #define O_DELETE 0x10000
3957 #endif
3958
3959 // Open a file. Unlink the file immediately after open returns
3960 // if the specified oflag has the O_DELETE flag set.
3961 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3962
3963 int os::open(const char *path, int oflag, int mode) {
3964
3965 if (strlen(path) > MAX_PATH - 1) {
3966 errno = ENAMETOOLONG;
3967 return -1;
3968 }
3969 int fd;
3970 int o_delete = (oflag & O_DELETE);
3971 oflag = oflag & ~O_DELETE;
3972
3973 fd = ::open(path, oflag, mode);
3974 if (fd == -1) return -1;
3975
3976 //If the open succeeded, the file might still be a directory
3977 {
3978 struct stat buf;
3979 int ret = ::fstat(fd, &buf);
3980 int st_mode = buf.st_mode;
3981
3982 if (ret != -1) {
3983 if ((st_mode & S_IFMT) == S_IFDIR) {
3984 errno = EISDIR;
3985 ::close(fd);
3986 return -1;
3987 }
3988 } else {
3989 ::close(fd);
3990 return -1;
3991 }
3992 }
3993
3994 /*
3995 * All file descriptors that are opened in the JVM and not
3996 * specifically destined for a subprocess should have the
3997 * close-on-exec flag set. If we don't set it, then careless 3rd
3998 * party native code might fork and exec without closing all
3999 * appropriate file descriptors (e.g. as we do in closeDescriptors in
4000 * UNIXProcess.c), and this in turn might:
4001 *
4002 * - cause end-of-file to fail to be detected on some file
4003 * descriptors, resulting in mysterious hangs, or
4004 *
4005 * - might cause an fopen in the subprocess to fail on a system
4006 * suffering from bug 1085341.
4007 *
4008 * (Yes, the default setting of the close-on-exec flag is a Unix
4009 * design flaw)
4010 *
4011 * See:
4012 * 1085341: 32-bit stdio routines should support file descriptors >255
4013 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4014 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4015 */
4016 #ifdef FD_CLOEXEC
4017 {
4018 int flags = ::fcntl(fd, F_GETFD);
4019 if (flags != -1)
4020 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4021 }
4022 #endif
4023
4024 if (o_delete != 0) {
4025 ::unlink(path);
4026 }
4027 return fd;
4028 }
4029
4030
4031 // create binary file, rewriting existing file if required
4032 int os::create_binary_file(const char* path, bool rewrite_existing) {
4033 int oflags = O_WRONLY | O_CREAT;
4034 if (!rewrite_existing) {
4035 oflags |= O_EXCL;
4036 }
4037 return ::open(path, oflags, S_IREAD | S_IWRITE);
4038 }
4039
4040 // return current position of file pointer
4041 jlong os::current_file_offset(int fd) {
4042 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4043 }
4044
4045 // move file pointer to the specified offset
4046 jlong os::seek_to_file_offset(int fd, jlong offset) {
4047 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4048 }
4049
4050 // This code originates from JDK's sysAvailable
4051 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4052
4053 int os::available(int fd, jlong *bytes) {
4054 jlong cur, end;
4055 int mode;
4056 struct stat buf;
4057
4058 if (::fstat(fd, &buf) >= 0) {
4059 mode = buf.st_mode;
4060 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4061 /*
4062 * XXX: is the following call interruptible? If so, this might
4063 * need to go through the INTERRUPT_IO() wrapper as for other
4064 * blocking, interruptible calls in this file.
4065 */
4066 int n;
4067 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4068 *bytes = n;
4069 return 1;
4070 }
4071 }
4072 }
4073 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4074 return 0;
4075 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4076 return 0;
4077 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4078 return 0;
4079 }
4080 *bytes = end - cur;
4081 return 1;
4082 }
4083
4084 int os::socket_available(int fd, jint *pbytes) {
4085 if (fd < 0)
4086 return OS_OK;
4087
4088 int ret;
4089
4090 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4091
4092 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4093 // is expected to return 0 on failure and 1 on success to the jdk.
4094
4095 return (ret == OS_ERR) ? 0 : 1;
4096 }
4097
4098 // Map a block of memory.
4099 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4100 char *addr, size_t bytes, bool read_only,
4101 bool allow_exec) {
4102 int prot;
4103 int flags;
4104
4105 if (read_only) {
4106 prot = PROT_READ;
4107 flags = MAP_SHARED;
4108 } else {
4109 prot = PROT_READ | PROT_WRITE;
4110 flags = MAP_PRIVATE;
4111 }
4112
4113 if (allow_exec) {
4114 prot |= PROT_EXEC;
4115 }
4116
4117 if (addr != NULL) {
4118 flags |= MAP_FIXED;
4119 }
4120
4121 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4122 fd, file_offset);
4123 if (mapped_address == MAP_FAILED) {
4124 return NULL;
4125 }
4126 return mapped_address;
4127 }
4128
4129
4130 // Remap a block of memory.
4131 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4132 char *addr, size_t bytes, bool read_only,
4133 bool allow_exec) {
4134 // same as map_memory() on this OS
4135 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4136 allow_exec);
4137 }
4138
4139
4140 // Unmap a block of memory.
4141 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4142 return munmap(addr, bytes) == 0;
4143 }
4144
4145 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4146 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4147 // of a thread.
4148 //
4149 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4150 // the fast estimate available on the platform.
4151
4152 jlong os::current_thread_cpu_time() {
4153 #ifdef __APPLE__
4154 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4155 #else
4156 Unimplemented();
4157 return 0;
4158 #endif
4159 }
4160
4161 jlong os::thread_cpu_time(Thread* thread) {
4162 #ifdef __APPLE__
4163 return os::thread_cpu_time(thread, true /* user + sys */);
4164 #else
4165 Unimplemented();
4166 return 0;
4167 #endif
4168 }
4169
4170 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4171 #ifdef __APPLE__
4172 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4173 #else
4174 Unimplemented();
4175 return 0;
4176 #endif
4177 }
4178
4179 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4180 #ifdef __APPLE__
4181 struct thread_basic_info tinfo;
4182 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4183 kern_return_t kr;
4184 thread_t mach_thread;
4185
4186 mach_thread = thread->osthread()->thread_id();
4187 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4188 if (kr != KERN_SUCCESS)
4189 return -1;
4190
4191 if (user_sys_cpu_time) {
4192 jlong nanos;
4193 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4194 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4195 return nanos;
4196 } else {
4197 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4198 }
4199 #else
4200 Unimplemented();
4201 return 0;
4202 #endif
4203 }
4204
4205
4206 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4207 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4208 info_ptr->may_skip_backward = false; // elapsed time not wall time
4209 info_ptr->may_skip_forward = false; // elapsed time not wall time
4210 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4211 }
4212
4213 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4214 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4215 info_ptr->may_skip_backward = false; // elapsed time not wall time
4216 info_ptr->may_skip_forward = false; // elapsed time not wall time
4217 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4218 }
4219
4220 bool os::is_thread_cpu_time_supported() {
4221 #ifdef __APPLE__
4222 return true;
4223 #else
4224 return false;
4225 #endif
4226 }
4227
4228 // System loadavg support. Returns -1 if load average cannot be obtained.
4229 // Bsd doesn't yet have a (official) notion of processor sets,
4230 // so just return the system wide load average.
4231 int os::loadavg(double loadavg[], int nelem) {
4232 return ::getloadavg(loadavg, nelem);
4233 }
4234
4235 void os::pause() {
4236 char filename[MAX_PATH];
4237 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4238 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4239 } else {
4240 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4241 }
4242
4243 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4244 if (fd != -1) {
4245 struct stat buf;
4246 ::close(fd);
4247 while (::stat(filename, &buf) == 0) {
4248 (void)::poll(NULL, 0, 100);
4249 }
4250 } else {
4251 jio_fprintf(stderr,
4252 "Could not open pause file '%s', continuing immediately.\n", filename);
4253 }
4254 }
4255
4256
4257 // Refer to the comments in os_solaris.cpp park-unpark.
4258 //
4259 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4260 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4261 // For specifics regarding the bug see GLIBC BUGID 261237 :
4262 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4263 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4264 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4265 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4266 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4267 // and monitorenter when we're using 1-0 locking. All those operations may result in
4268 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4269 // of libpthread avoids the problem, but isn't practical.
4270 //
4271 // Possible remedies:
4272 //
4273 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4274 // This is palliative and probabilistic, however. If the thread is preempted
4275 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4276 // than the minimum period may have passed, and the abstime may be stale (in the
4277 // past) resultin in a hang. Using this technique reduces the odds of a hang
4278 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4279 //
4280 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4281 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4282 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4283 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4284 // thread.
4285 //
4286 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4287 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4288 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4289 // This also works well. In fact it avoids kernel-level scalability impediments
4290 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4291 // timers in a graceful fashion.
4292 //
4293 // 4. When the abstime value is in the past it appears that control returns
4294 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4295 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4296 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4297 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4298 // It may be possible to avoid reinitialization by checking the return
4299 // value from pthread_cond_timedwait(). In addition to reinitializing the
4300 // condvar we must establish the invariant that cond_signal() is only called
4301 // within critical sections protected by the adjunct mutex. This prevents
4302 // cond_signal() from "seeing" a condvar that's in the midst of being
4303 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4304 // desirable signal-after-unlock optimization that avoids futile context switching.
4305 //
4306 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4307 // structure when a condvar is used or initialized. cond_destroy() would
4308 // release the helper structure. Our reinitialize-after-timedwait fix
4309 // put excessive stress on malloc/free and locks protecting the c-heap.
4310 //
4311 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4312 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4313 // and only enabling the work-around for vulnerable environments.
4314
4315 // utility to compute the abstime argument to timedwait:
4316 // millis is the relative timeout time
4317 // abstime will be the absolute timeout time
4318 // TODO: replace compute_abstime() with unpackTime()
4319
4320 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4321 if (millis < 0) millis = 0;
4322 struct timeval now;
4323 int status = gettimeofday(&now, NULL);
4324 assert(status == 0, "gettimeofday");
4325 jlong seconds = millis / 1000;
4326 millis %= 1000;
4327 if (seconds > 50000000) { // see man cond_timedwait(3T)
4328 seconds = 50000000;
4329 }
4330 abstime->tv_sec = now.tv_sec + seconds;
4331 long usec = now.tv_usec + millis * 1000;
4332 if (usec >= 1000000) {
4333 abstime->tv_sec += 1;
4334 usec -= 1000000;
4335 }
4336 abstime->tv_nsec = usec * 1000;
4337 return abstime;
4338 }
4339
4340
4341 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4342 // Conceptually TryPark() should be equivalent to park(0).
4343
4344 int os::PlatformEvent::TryPark() {
4345 for (;;) {
4346 const int v = _Event ;
4347 guarantee ((v == 0) || (v == 1), "invariant") ;
4348 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4349 }
4350 }
4351
4352 void os::PlatformEvent::park() { // AKA "down()"
4353 // Invariant: Only the thread associated with the Event/PlatformEvent
4354 // may call park().
4355 // TODO: assert that _Assoc != NULL or _Assoc == Self
4356 int v ;
4357 for (;;) {
4358 v = _Event ;
4359 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4360 }
4361 guarantee (v >= 0, "invariant") ;
4362 if (v == 0) {
4363 // Do this the hard way by blocking ...
4364 int status = pthread_mutex_lock(_mutex);
4365 assert_status(status == 0, status, "mutex_lock");
4366 guarantee (_nParked == 0, "invariant") ;
4367 ++ _nParked ;
4368 while (_Event < 0) {
4369 status = pthread_cond_wait(_cond, _mutex);
4370 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4371 // Treat this the same as if the wait was interrupted
4372 if (status == ETIMEDOUT) { status = EINTR; }
4373 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4374 }
4375 -- _nParked ;
4376
4377 _Event = 0 ;
4378 status = pthread_mutex_unlock(_mutex);
4379 assert_status(status == 0, status, "mutex_unlock");
4380 // Paranoia to ensure our locked and lock-free paths interact
4381 // correctly with each other.
4382 OrderAccess::fence();
4383 }
4384 guarantee (_Event >= 0, "invariant") ;
4385 }
4386
4387 int os::PlatformEvent::park(jlong millis) {
4388 guarantee (_nParked == 0, "invariant") ;
4389
4390 int v ;
4391 for (;;) {
4392 v = _Event ;
4393 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4394 }
4395 guarantee (v >= 0, "invariant") ;
4396 if (v != 0) return OS_OK ;
4397
4398 // We do this the hard way, by blocking the thread.
4399 // Consider enforcing a minimum timeout value.
4400 struct timespec abst;
4401 compute_abstime(&abst, millis);
4402
4403 int ret = OS_TIMEOUT;
4404 int status = pthread_mutex_lock(_mutex);
4405 assert_status(status == 0, status, "mutex_lock");
4406 guarantee (_nParked == 0, "invariant") ;
4407 ++_nParked ;
4408
4409 // Object.wait(timo) will return because of
4410 // (a) notification
4411 // (b) timeout
4412 // (c) thread.interrupt
4413 //
4414 // Thread.interrupt and object.notify{All} both call Event::set.
4415 // That is, we treat thread.interrupt as a special case of notification.
4416 // The underlying Solaris implementation, cond_timedwait, admits
4417 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4418 // JVM from making those visible to Java code. As such, we must
4419 // filter out spurious wakeups. We assume all ETIME returns are valid.
4420 //
4421 // TODO: properly differentiate simultaneous notify+interrupt.
4422 // In that case, we should propagate the notify to another waiter.
4423
4424 while (_Event < 0) {
4425 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4426 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4427 pthread_cond_destroy (_cond);
4428 pthread_cond_init (_cond, NULL) ;
4429 }
4430 assert_status(status == 0 || status == EINTR ||
4431 status == ETIMEDOUT,
4432 status, "cond_timedwait");
4433 if (!FilterSpuriousWakeups) break ; // previous semantics
4434 if (status == ETIMEDOUT) break ;
4435 // We consume and ignore EINTR and spurious wakeups.
4436 }
4437 --_nParked ;
4438 if (_Event >= 0) {
4439 ret = OS_OK;
4440 }
4441 _Event = 0 ;
4442 status = pthread_mutex_unlock(_mutex);
4443 assert_status(status == 0, status, "mutex_unlock");
4444 assert (_nParked == 0, "invariant") ;
4445 // Paranoia to ensure our locked and lock-free paths interact
4446 // correctly with each other.
4447 OrderAccess::fence();
4448 return ret;
4449 }
4450
4451 void os::PlatformEvent::unpark() {
4452 // Transitions for _Event:
4453 // 0 :=> 1
4454 // 1 :=> 1
4455 // -1 :=> either 0 or 1; must signal target thread
4456 // That is, we can safely transition _Event from -1 to either
4457 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4458 // unpark() calls.
4459 // See also: "Semaphores in Plan 9" by Mullender & Cox
4460 //
4461 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4462 // that it will take two back-to-back park() calls for the owning
4463 // thread to block. This has the benefit of forcing a spurious return
4464 // from the first park() call after an unpark() call which will help
4465 // shake out uses of park() and unpark() without condition variables.
4466
4467 if (Atomic::xchg(1, &_Event) >= 0) return;
4468
4469 // Wait for the thread associated with the event to vacate
4470 int status = pthread_mutex_lock(_mutex);
4471 assert_status(status == 0, status, "mutex_lock");
4472 int AnyWaiters = _nParked;
4473 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4474 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4475 AnyWaiters = 0;
4476 pthread_cond_signal(_cond);
4477 }
4478 status = pthread_mutex_unlock(_mutex);
4479 assert_status(status == 0, status, "mutex_unlock");
4480 if (AnyWaiters != 0) {
4481 status = pthread_cond_signal(_cond);
4482 assert_status(status == 0, status, "cond_signal");
4483 }
4484
4485 // Note that we signal() _after dropping the lock for "immortal" Events.
4486 // This is safe and avoids a common class of futile wakeups. In rare
4487 // circumstances this can cause a thread to return prematurely from
4488 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4489 // simply re-test the condition and re-park itself.
4490 }
4491
4492
4493 // JSR166
4494 // -------------------------------------------------------
4495
4496 /*
4497 * The solaris and bsd implementations of park/unpark are fairly
4498 * conservative for now, but can be improved. They currently use a
4499 * mutex/condvar pair, plus a a count.
4500 * Park decrements count if > 0, else does a condvar wait. Unpark
4501 * sets count to 1 and signals condvar. Only one thread ever waits
4502 * on the condvar. Contention seen when trying to park implies that someone
4503 * is unparking you, so don't wait. And spurious returns are fine, so there
4504 * is no need to track notifications.
4505 */
4506
4507 #define MAX_SECS 100000000
4508 /*
4509 * This code is common to bsd and solaris and will be moved to a
4510 * common place in dolphin.
4511 *
4512 * The passed in time value is either a relative time in nanoseconds
4513 * or an absolute time in milliseconds. Either way it has to be unpacked
4514 * into suitable seconds and nanoseconds components and stored in the
4515 * given timespec structure.
4516 * Given time is a 64-bit value and the time_t used in the timespec is only
4517 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4518 * overflow if times way in the future are given. Further on Solaris versions
4519 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4520 * number of seconds, in abstime, is less than current_time + 100,000,000.
4521 * As it will be 28 years before "now + 100000000" will overflow we can
4522 * ignore overflow and just impose a hard-limit on seconds using the value
4523 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4524 * years from "now".
4525 */
4526
4527 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4528 assert (time > 0, "convertTime");
4529
4530 struct timeval now;
4531 int status = gettimeofday(&now, NULL);
4532 assert(status == 0, "gettimeofday");
4533
4534 time_t max_secs = now.tv_sec + MAX_SECS;
4535
4536 if (isAbsolute) {
4537 jlong secs = time / 1000;
4538 if (secs > max_secs) {
4539 absTime->tv_sec = max_secs;
4540 }
4541 else {
4542 absTime->tv_sec = secs;
4543 }
4544 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4545 }
4546 else {
4547 jlong secs = time / NANOSECS_PER_SEC;
4548 if (secs >= MAX_SECS) {
4549 absTime->tv_sec = max_secs;
4550 absTime->tv_nsec = 0;
4551 }
4552 else {
4553 absTime->tv_sec = now.tv_sec + secs;
4554 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4555 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4556 absTime->tv_nsec -= NANOSECS_PER_SEC;
4557 ++absTime->tv_sec; // note: this must be <= max_secs
4558 }
4559 }
4560 }
4561 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4562 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4563 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4564 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4565 }
4566
4567 void Parker::park(bool isAbsolute, jlong time) {
4568 // Ideally we'd do something useful while spinning, such
4569 // as calling unpackTime().
4570
4571 // Optional fast-path check:
4572 // Return immediately if a permit is available.
4573 // We depend on Atomic::xchg() having full barrier semantics
4574 // since we are doing a lock-free update to _counter.
4575 if (Atomic::xchg(0, &_counter) > 0) return;
4576
4577 Thread* thread = Thread::current();
4578 assert(thread->is_Java_thread(), "Must be JavaThread");
4579 JavaThread *jt = (JavaThread *)thread;
4580
4581 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4582 // Check interrupt before trying to wait
4583 if (Thread::is_interrupted(thread, false)) {
4584 return;
4585 }
4586
4587 // Next, demultiplex/decode time arguments
4588 struct timespec absTime;
4589 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4590 return;
4591 }
4592 if (time > 0) {
4593 unpackTime(&absTime, isAbsolute, time);
4594 }
4595
4596
4597 // Enter safepoint region
4598 // Beware of deadlocks such as 6317397.
4599 // The per-thread Parker:: mutex is a classic leaf-lock.
4600 // In particular a thread must never block on the Threads_lock while
4601 // holding the Parker:: mutex. If safepoints are pending both the
4602 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4603 ThreadBlockInVM tbivm(jt);
4604
4605 // Don't wait if cannot get lock since interference arises from
4606 // unblocking. Also. check interrupt before trying wait
4607 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4608 return;
4609 }
4610
4611 int status ;
4612 if (_counter > 0) { // no wait needed
4613 _counter = 0;
4614 status = pthread_mutex_unlock(_mutex);
4615 assert (status == 0, "invariant") ;
4616 // Paranoia to ensure our locked and lock-free paths interact
4617 // correctly with each other and Java-level accesses.
4618 OrderAccess::fence();
4619 return;
4620 }
4621
4622 #ifdef ASSERT
4623 // Don't catch signals while blocked; let the running threads have the signals.
4624 // (This allows a debugger to break into the running thread.)
4625 sigset_t oldsigs;
4626 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4627 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4628 #endif
4629
4630 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4631 jt->set_suspend_equivalent();
4632 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4633
4634 if (time == 0) {
4635 status = pthread_cond_wait (_cond, _mutex) ;
4636 } else {
4637 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4638 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4639 pthread_cond_destroy (_cond) ;
4640 pthread_cond_init (_cond, NULL);
4641 }
4642 }
4643 assert_status(status == 0 || status == EINTR ||
4644 status == ETIMEDOUT,
4645 status, "cond_timedwait");
4646
4647 #ifdef ASSERT
4648 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4649 #endif
4650
4651 _counter = 0 ;
4652 status = pthread_mutex_unlock(_mutex) ;
4653 assert_status(status == 0, status, "invariant") ;
4654 // Paranoia to ensure our locked and lock-free paths interact
4655 // correctly with each other and Java-level accesses.
4656 OrderAccess::fence();
4657
4658 // If externally suspended while waiting, re-suspend
4659 if (jt->handle_special_suspend_equivalent_condition()) {
4660 jt->java_suspend_self();
4661 }
4662 }
4663
4664 void Parker::unpark() {
4665 int s, status ;
4666 status = pthread_mutex_lock(_mutex);
4667 assert (status == 0, "invariant") ;
4668 s = _counter;
4669 _counter = 1;
4670 if (s < 1) {
4671 if (WorkAroundNPTLTimedWaitHang) {
4672 status = pthread_cond_signal (_cond) ;
4673 assert (status == 0, "invariant") ;
4674 status = pthread_mutex_unlock(_mutex);
4675 assert (status == 0, "invariant") ;
4676 } else {
4677 status = pthread_mutex_unlock(_mutex);
4678 assert (status == 0, "invariant") ;
4679 status = pthread_cond_signal (_cond) ;
4680 assert (status == 0, "invariant") ;
4681 }
4682 } else {
4683 pthread_mutex_unlock(_mutex);
4684 assert (status == 0, "invariant") ;
4685 }
4686 }
4687
4688
4689 /* Darwin has no "environ" in a dynamic library. */
4690 #ifdef __APPLE__
4691 #include <crt_externs.h>
4692 #define environ (*_NSGetEnviron())
4693 #else
4694 extern char** environ;
4695 #endif
4696
4697 // Run the specified command in a separate process. Return its exit value,
4698 // or -1 on failure (e.g. can't fork a new process).
4699 // Unlike system(), this function can be called from signal handler. It
4700 // doesn't block SIGINT et al.
4701 int os::fork_and_exec(char* cmd) {
4702 const char * argv[4] = {"sh", "-c", cmd, NULL};
4703
4704 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4705 // pthread_atfork handlers and reset pthread library. All we need is a
4706 // separate process to execve. Make a direct syscall to fork process.
4707 // On IA64 there's no fork syscall, we have to use fork() and hope for
4708 // the best...
4709 pid_t pid = fork();
4710
4711 if (pid < 0) {
4712 // fork failed
4713 return -1;
4714
4715 } else if (pid == 0) {
4716 // child process
4717
4718 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4719 // first to kill every thread on the thread list. Because this list is
4720 // not reset by fork() (see notes above), execve() will instead kill
4721 // every thread in the parent process. We know this is the only thread
4722 // in the new process, so make a system call directly.
4723 // IA64 should use normal execve() from glibc to match the glibc fork()
4724 // above.
4725 execve("/bin/sh", (char* const*)argv, environ);
4726
4727 // execve failed
4728 _exit(-1);
4729
4730 } else {
4731 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4732 // care about the actual exit code, for now.
4733
4734 int status;
4735
4736 // Wait for the child process to exit. This returns immediately if
4737 // the child has already exited. */
4738 while (waitpid(pid, &status, 0) < 0) {
4739 switch (errno) {
4740 case ECHILD: return 0;
4741 case EINTR: break;
4742 default: return -1;
4743 }
4744 }
4745
4746 if (WIFEXITED(status)) {
4747 // The child exited normally; get its exit code.
4748 return WEXITSTATUS(status);
4749 } else if (WIFSIGNALED(status)) {
4750 // The child exited because of a signal
4751 // The best value to return is 0x80 + signal number,
4752 // because that is what all Unix shells do, and because
4753 // it allows callers to distinguish between process exit and
4754 // process death by signal.
4755 return 0x80 + WTERMSIG(status);
4756 } else {
4757 // Unknown exit code; pass it through
4758 return status;
4759 }
4760 }
4761 }
4762
4763 // is_headless_jre()
4764 //
4765 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4766 // in order to report if we are running in a headless jre
4767 //
4768 // Since JDK8 xawt/libmawt.so was moved into the same directory
4769 // as libawt.so, and renamed libawt_xawt.so
4770 //
4771 bool os::is_headless_jre() {
4772 #ifdef __APPLE__
4773 // We no longer build headless-only on Mac OS X
4774 return false;
4775 #else
4776 struct stat statbuf;
4777 char buf[MAXPATHLEN];
4778 char libmawtpath[MAXPATHLEN];
4779 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4780 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4781 char *p;
4782
4783 // Get path to libjvm.so
4784 os::jvm_path(buf, sizeof(buf));
4785
4786 // Get rid of libjvm.so
4787 p = strrchr(buf, '/');
4788 if (p == NULL) return false;
4789 else *p = '\0';
4790
4791 // Get rid of client or server
4792 p = strrchr(buf, '/');
4793 if (p == NULL) return false;
4794 else *p = '\0';
4795
4796 // check xawt/libmawt.so
4797 strcpy(libmawtpath, buf);
4798 strcat(libmawtpath, xawtstr);
4799 if (::stat(libmawtpath, &statbuf) == 0) return false;
4800
4801 // check libawt_xawt.so
4802 strcpy(libmawtpath, buf);
4803 strcat(libmawtpath, new_xawtstr);
4804 if (::stat(libmawtpath, &statbuf) == 0) return false;
4805
4806 return true;
4807 #endif
4808 }
4809
4810 // Get the default path to the core file
4811 // Returns the length of the string
4812 int os::get_core_path(char* buffer, size_t bufferSize) {
4813 int n = jio_snprintf(buffer, bufferSize, "/cores");
4814
4815 // Truncate if theoretical string was longer than bufferSize
4816 n = MIN2(n, (int)bufferSize);
4817
4818 return n;
4819 }
4820
4821 #ifndef PRODUCT
4822 void TestReserveMemorySpecial_test() {
4823 // No tests available for this platform
4824 }
4825 #endif