1 /*
2 * Copyright (c) 1999, 2016, 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 "logging/log.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "memory/filemap.hpp"
38 #include "mutex_bsd.inline.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "os_bsd.inline.hpp"
41 #include "os_share_bsd.hpp"
42 #include "prims/jniFastGetField.hpp"
43 #include "prims/jvm.h"
44 #include "prims/jvm_misc.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/atomic.inline.hpp"
47 #include "runtime/extendedPC.hpp"
48 #include "runtime/globals.hpp"
49 #include "runtime/interfaceSupport.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/objectMonitor.hpp"
54 #include "runtime/orderAccess.inline.hpp"
55 #include "runtime/osThread.hpp"
56 #include "runtime/perfMemory.hpp"
57 #include "runtime/sharedRuntime.hpp"
58 #include "runtime/statSampler.hpp"
59 #include "runtime/stubRoutines.hpp"
60 #include "runtime/thread.inline.hpp"
61 #include "runtime/threadCritical.hpp"
62 #include "runtime/timer.hpp"
63 #include "semaphore_bsd.hpp"
64 #include "services/attachListener.hpp"
65 #include "services/memTracker.hpp"
66 #include "services/runtimeService.hpp"
67 #include "utilities/decoder.hpp"
68 #include "utilities/defaultStream.hpp"
69 #include "utilities/events.hpp"
70 #include "utilities/growableArray.hpp"
71 #include "utilities/vmError.hpp"
72
73 // put OS-includes here
74 # include <sys/types.h>
75 # include <sys/mman.h>
76 # include <sys/stat.h>
77 # include <sys/select.h>
78 # include <pthread.h>
79 # include <signal.h>
80 # include <errno.h>
81 # include <dlfcn.h>
82 # include <stdio.h>
83 # include <unistd.h>
84 # include <sys/resource.h>
85 # include <pthread.h>
86 # include <sys/stat.h>
87 # include <sys/time.h>
88 # include <sys/times.h>
89 # include <sys/utsname.h>
90 # include <sys/socket.h>
91 # include <sys/wait.h>
92 # include <time.h>
93 # include <pwd.h>
94 # include <poll.h>
95 # include <semaphore.h>
96 # include <fcntl.h>
97 # include <string.h>
98 # include <sys/param.h>
99 # include <sys/sysctl.h>
100 # include <sys/ipc.h>
101 # include <sys/shm.h>
102 #ifndef __APPLE__
103 # include <link.h>
104 #endif
105 # include <stdint.h>
106 # include <inttypes.h>
107 # include <sys/ioctl.h>
108 # include <sys/syscall.h>
109
110 #if defined(__FreeBSD__) || defined(__NetBSD__)
111 #include <elf.h>
112 #endif
113
114 #ifdef __APPLE__
115 #include <mach/mach.h> // semaphore_* API
116 #include <mach-o/dyld.h>
117 #include <sys/proc_info.h>
118 #include <objc/objc-auto.h>
119 #endif
120
121 #ifndef MAP_ANONYMOUS
122 #define MAP_ANONYMOUS MAP_ANON
123 #endif
124
125 #define MAX_PATH (2 * K)
126
127 // for timer info max values which include all bits
128 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
129
130 #define LARGEPAGES_BIT (1 << 6)
131
132 ////////////////////////////////////////////////////////////////////////////////
133 // global variables
134 julong os::Bsd::_physical_memory = 0;
135
136 #ifdef __APPLE__
137 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
138 volatile uint64_t os::Bsd::_max_abstime = 0;
139 #else
140 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
141 #endif
142 pthread_t os::Bsd::_main_thread;
143 int os::Bsd::_page_size = -1;
144
145 static jlong initial_time_count=0;
146
147 static int clock_tics_per_sec = 100;
148
149 // For diagnostics to print a message once. see run_periodic_checks
150 static sigset_t check_signal_done;
151 static bool check_signals = true;
152
153 static pid_t _initial_pid = 0;
154
155 // Signal number used to suspend/resume a thread
156
157 // do not use any signal number less than SIGSEGV, see 4355769
158 static int SR_signum = SIGUSR2;
159 sigset_t SR_sigset;
160
161
162 ////////////////////////////////////////////////////////////////////////////////
163 // utility functions
164
165 static int SR_initialize();
166 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
167
168 julong os::available_memory() {
169 return Bsd::available_memory();
170 }
171
172 // available here means free
173 julong os::Bsd::available_memory() {
174 uint64_t available = physical_memory() >> 2;
175 #ifdef __APPLE__
176 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
177 vm_statistics64_data_t vmstat;
178 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
179 (host_info64_t)&vmstat, &count);
180 assert(kerr == KERN_SUCCESS,
181 "host_statistics64 failed - check mach_host_self() and count");
182 if (kerr == KERN_SUCCESS) {
183 available = vmstat.free_count * os::vm_page_size();
184 }
185 #endif
186 return available;
187 }
188
189 julong os::physical_memory() {
190 return Bsd::physical_memory();
191 }
192
193 // Return true if user is running as root.
194
195 bool os::have_special_privileges() {
196 static bool init = false;
197 static bool privileges = false;
198 if (!init) {
199 privileges = (getuid() != geteuid()) || (getgid() != getegid());
200 init = true;
201 }
202 return privileges;
203 }
204
205
206
207 // Cpu architecture string
208 #if defined(ZERO)
209 static char cpu_arch[] = ZERO_LIBARCH;
210 #elif defined(IA64)
211 static char cpu_arch[] = "ia64";
212 #elif defined(IA32)
213 static char cpu_arch[] = "i386";
214 #elif defined(AMD64)
215 static char cpu_arch[] = "amd64";
216 #elif defined(ARM)
217 static char cpu_arch[] = "arm";
218 #elif defined(PPC32)
219 static char cpu_arch[] = "ppc";
220 #elif defined(SPARC)
221 #ifdef _LP64
222 static char cpu_arch[] = "sparcv9";
223 #else
224 static char cpu_arch[] = "sparc";
225 #endif
226 #else
227 #error Add appropriate cpu_arch setting
228 #endif
229
230 // Compiler variant
231 #ifdef COMPILER2
232 #define COMPILER_VARIANT "server"
233 #else
234 #define COMPILER_VARIANT "client"
235 #endif
236
237
238 void os::Bsd::initialize_system_info() {
239 int mib[2];
240 size_t len;
241 int cpu_val;
242 julong mem_val;
243
244 // get processors count via hw.ncpus sysctl
245 mib[0] = CTL_HW;
246 mib[1] = HW_NCPU;
247 len = sizeof(cpu_val);
248 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
249 assert(len == sizeof(cpu_val), "unexpected data size");
250 set_processor_count(cpu_val);
251 } else {
252 set_processor_count(1); // fallback
253 }
254
255 // get physical memory via hw.memsize sysctl (hw.memsize is used
256 // since it returns a 64 bit value)
257 mib[0] = CTL_HW;
258
259 #if defined (HW_MEMSIZE) // Apple
260 mib[1] = HW_MEMSIZE;
261 #elif defined(HW_PHYSMEM) // Most of BSD
262 mib[1] = HW_PHYSMEM;
263 #elif defined(HW_REALMEM) // Old FreeBSD
264 mib[1] = HW_REALMEM;
265 #else
266 #error No ways to get physmem
267 #endif
268
269 len = sizeof(mem_val);
270 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
271 assert(len == sizeof(mem_val), "unexpected data size");
272 _physical_memory = mem_val;
273 } else {
274 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
275 }
276
277 #ifdef __OpenBSD__
278 {
279 // limit _physical_memory memory view on OpenBSD since
280 // datasize rlimit restricts us anyway.
281 struct rlimit limits;
282 getrlimit(RLIMIT_DATA, &limits);
283 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
284 }
285 #endif
286 }
287
288 #ifdef __APPLE__
289 static const char *get_home() {
290 const char *home_dir = ::getenv("HOME");
291 if ((home_dir == NULL) || (*home_dir == '\0')) {
292 struct passwd *passwd_info = getpwuid(geteuid());
293 if (passwd_info != NULL) {
294 home_dir = passwd_info->pw_dir;
295 }
296 }
297
298 return home_dir;
299 }
300 #endif
301
302 void os::init_system_properties_values() {
303 // The next steps are taken in the product version:
304 //
305 // Obtain the JAVA_HOME value from the location of libjvm.so.
306 // This library should be located at:
307 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
308 //
309 // If "/jre/lib/" appears at the right place in the path, then we
310 // assume libjvm.so is installed in a JDK and we use this path.
311 //
312 // Otherwise exit with message: "Could not create the Java virtual machine."
313 //
314 // The following extra steps are taken in the debugging version:
315 //
316 // If "/jre/lib/" does NOT appear at the right place in the path
317 // instead of exit check for $JAVA_HOME environment variable.
318 //
319 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
320 // then we append a fake suffix "hotspot/libjvm.so" to this path so
321 // it looks like libjvm.so is installed there
322 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
323 //
324 // Otherwise exit.
325 //
326 // Important note: if the location of libjvm.so changes this
327 // code needs to be changed accordingly.
328
329 // See ld(1):
330 // The linker uses the following search paths to locate required
331 // shared libraries:
332 // 1: ...
333 // ...
334 // 7: The default directories, normally /lib and /usr/lib.
335 #ifndef DEFAULT_LIBPATH
336 #define DEFAULT_LIBPATH "/lib:/usr/lib"
337 #endif
338
339 // Base path of extensions installed on the system.
340 #define SYS_EXT_DIR "/usr/java/packages"
341 #define EXTENSIONS_DIR "/lib/ext"
342
343 #ifndef __APPLE__
344
345 // Buffer that fits several sprintfs.
346 // Note that the space for the colon and the trailing null are provided
347 // by the nulls included by the sizeof operator.
348 const size_t bufsize =
349 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
350 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
351 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
352
353 // sysclasspath, java_home, dll_dir
354 {
355 char *pslash;
356 os::jvm_path(buf, bufsize);
357
358 // Found the full path to libjvm.so.
359 // Now cut the path to <java_home>/jre if we can.
360 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
361 pslash = strrchr(buf, '/');
362 if (pslash != NULL) {
363 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
364 }
365 Arguments::set_dll_dir(buf);
366
367 if (pslash != NULL) {
368 pslash = strrchr(buf, '/');
369 if (pslash != NULL) {
370 *pslash = '\0'; // Get rid of /<arch>.
371 pslash = strrchr(buf, '/');
372 if (pslash != NULL) {
373 *pslash = '\0'; // Get rid of /lib.
374 }
375 }
376 }
377 Arguments::set_java_home(buf);
378 set_boot_path('/', ':');
379 }
380
381 // Where to look for native libraries.
382 //
383 // Note: Due to a legacy implementation, most of the library path
384 // is set in the launcher. This was to accomodate linking restrictions
385 // on legacy Bsd implementations (which are no longer supported).
386 // Eventually, all the library path setting will be done here.
387 //
388 // However, to prevent the proliferation of improperly built native
389 // libraries, the new path component /usr/java/packages is added here.
390 // Eventually, all the library path setting will be done here.
391 {
392 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
393 // should always exist (until the legacy problem cited above is
394 // addressed).
395 const char *v = ::getenv("LD_LIBRARY_PATH");
396 const char *v_colon = ":";
397 if (v == NULL) { v = ""; v_colon = ""; }
398 // That's +1 for the colon and +1 for the trailing '\0'.
399 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
400 strlen(v) + 1 +
401 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
402 mtInternal);
403 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
404 Arguments::set_library_path(ld_library_path);
405 FREE_C_HEAP_ARRAY(char, ld_library_path);
406 }
407
408 // Extensions directories.
409 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
410 Arguments::set_ext_dirs(buf);
411
412 FREE_C_HEAP_ARRAY(char, buf);
413
414 #else // __APPLE__
415
416 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
417 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
418
419 const char *user_home_dir = get_home();
420 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
421 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
422 sizeof(SYS_EXTENSIONS_DIRS);
423
424 // Buffer that fits several sprintfs.
425 // Note that the space for the colon and the trailing null are provided
426 // by the nulls included by the sizeof operator.
427 const size_t bufsize =
428 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
429 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
430 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
431
432 // sysclasspath, java_home, dll_dir
433 {
434 char *pslash;
435 os::jvm_path(buf, bufsize);
436
437 // Found the full path to libjvm.so.
438 // Now cut the path to <java_home>/jre if we can.
439 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
440 pslash = strrchr(buf, '/');
441 if (pslash != NULL) {
442 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
443 }
444 #ifdef STATIC_BUILD
445 strcat(buf, "/lib");
446 #endif
447
448 Arguments::set_dll_dir(buf);
449
450 if (pslash != NULL) {
451 pslash = strrchr(buf, '/');
452 if (pslash != NULL) {
453 *pslash = '\0'; // Get rid of /lib.
454 }
455 }
456 Arguments::set_java_home(buf);
457 set_boot_path('/', ':');
458 }
459
460 // Where to look for native libraries.
461 //
462 // Note: Due to a legacy implementation, most of the library path
463 // is set in the launcher. This was to accomodate linking restrictions
464 // on legacy Bsd implementations (which are no longer supported).
465 // Eventually, all the library path setting will be done here.
466 //
467 // However, to prevent the proliferation of improperly built native
468 // libraries, the new path component /usr/java/packages is added here.
469 // Eventually, all the library path setting will be done here.
470 {
471 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
472 // should always exist (until the legacy problem cited above is
473 // addressed).
474 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
475 // can specify a directory inside an app wrapper
476 const char *l = ::getenv("JAVA_LIBRARY_PATH");
477 const char *l_colon = ":";
478 if (l == NULL) { l = ""; l_colon = ""; }
479
480 const char *v = ::getenv("DYLD_LIBRARY_PATH");
481 const char *v_colon = ":";
482 if (v == NULL) { v = ""; v_colon = ""; }
483
484 // Apple's Java6 has "." at the beginning of java.library.path.
485 // OpenJDK on Windows has "." at the end of java.library.path.
486 // OpenJDK on Linux and Solaris don't have "." in java.library.path
487 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
488 // "." is appended to the end of java.library.path. Yes, this
489 // could cause a change in behavior, but Apple's Java6 behavior
490 // can be achieved by putting "." at the beginning of the
491 // JAVA_LIBRARY_PATH environment variable.
492 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
493 strlen(v) + 1 + strlen(l) + 1 +
494 system_ext_size + 3,
495 mtInternal);
496 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
497 v, v_colon, l, l_colon, user_home_dir);
498 Arguments::set_library_path(ld_library_path);
499 FREE_C_HEAP_ARRAY(char, ld_library_path);
500 }
501
502 // Extensions directories.
503 //
504 // Note that the space for the colon and the trailing null are provided
505 // by the nulls included by the sizeof operator (so actually one byte more
506 // than necessary is allocated).
507 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
508 user_home_dir, Arguments::get_java_home());
509 Arguments::set_ext_dirs(buf);
510
511 FREE_C_HEAP_ARRAY(char, buf);
512
513 #undef SYS_EXTENSIONS_DIR
514 #undef SYS_EXTENSIONS_DIRS
515
516 #endif // __APPLE__
517
518 #undef SYS_EXT_DIR
519 #undef EXTENSIONS_DIR
520 }
521
522 ////////////////////////////////////////////////////////////////////////////////
523 // breakpoint support
524
525 void os::breakpoint() {
526 BREAKPOINT;
527 }
528
529 extern "C" void breakpoint() {
530 // use debugger to set breakpoint here
531 }
532
533 ////////////////////////////////////////////////////////////////////////////////
534 // signal support
535
536 debug_only(static bool signal_sets_initialized = false);
537 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
538
539 bool os::Bsd::is_sig_ignored(int sig) {
540 struct sigaction oact;
541 sigaction(sig, (struct sigaction*)NULL, &oact);
542 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
543 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
544 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
545 return true;
546 } else {
547 return false;
548 }
549 }
550
551 void os::Bsd::signal_sets_init() {
552 // Should also have an assertion stating we are still single-threaded.
553 assert(!signal_sets_initialized, "Already initialized");
554 // Fill in signals that are necessarily unblocked for all threads in
555 // the VM. Currently, we unblock the following signals:
556 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
557 // by -Xrs (=ReduceSignalUsage));
558 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
559 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
560 // the dispositions or masks wrt these signals.
561 // Programs embedding the VM that want to use the above signals for their
562 // own purposes must, at this time, use the "-Xrs" option to prevent
563 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
564 // (See bug 4345157, and other related bugs).
565 // In reality, though, unblocking these signals is really a nop, since
566 // these signals are not blocked by default.
567 sigemptyset(&unblocked_sigs);
568 sigemptyset(&allowdebug_blocked_sigs);
569 sigaddset(&unblocked_sigs, SIGILL);
570 sigaddset(&unblocked_sigs, SIGSEGV);
571 sigaddset(&unblocked_sigs, SIGBUS);
572 sigaddset(&unblocked_sigs, SIGFPE);
573 sigaddset(&unblocked_sigs, SR_signum);
574
575 if (!ReduceSignalUsage) {
576 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
577 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
578 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
579 }
580 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
581 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
582 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
583 }
584 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
585 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
586 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
587 }
588 }
589 // Fill in signals that are blocked by all but the VM thread.
590 sigemptyset(&vm_sigs);
591 if (!ReduceSignalUsage) {
592 sigaddset(&vm_sigs, BREAK_SIGNAL);
593 }
594 debug_only(signal_sets_initialized = true);
595
596 }
597
598 // These are signals that are unblocked while a thread is running Java.
599 // (For some reason, they get blocked by default.)
600 sigset_t* os::Bsd::unblocked_signals() {
601 assert(signal_sets_initialized, "Not initialized");
602 return &unblocked_sigs;
603 }
604
605 // These are the signals that are blocked while a (non-VM) thread is
606 // running Java. Only the VM thread handles these signals.
607 sigset_t* os::Bsd::vm_signals() {
608 assert(signal_sets_initialized, "Not initialized");
609 return &vm_sigs;
610 }
611
612 // These are signals that are blocked during cond_wait to allow debugger in
613 sigset_t* os::Bsd::allowdebug_blocked_signals() {
614 assert(signal_sets_initialized, "Not initialized");
615 return &allowdebug_blocked_sigs;
616 }
617
618 void os::Bsd::hotspot_sigmask(Thread* thread) {
619
620 //Save caller's signal mask before setting VM signal mask
621 sigset_t caller_sigmask;
622 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
623
624 OSThread* osthread = thread->osthread();
625 osthread->set_caller_sigmask(caller_sigmask);
626
627 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
628
629 if (!ReduceSignalUsage) {
630 if (thread->is_VM_thread()) {
631 // Only the VM thread handles BREAK_SIGNAL ...
632 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
633 } else {
634 // ... all other threads block BREAK_SIGNAL
635 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
636 }
637 }
638 }
639
640
641 //////////////////////////////////////////////////////////////////////////////
642 // create new thread
643
644 #ifdef __APPLE__
645 // library handle for calling objc_registerThreadWithCollector()
646 // without static linking to the libobjc library
647 #define OBJC_LIB "/usr/lib/libobjc.dylib"
648 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
649 typedef void (*objc_registerThreadWithCollector_t)();
650 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
651 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
652 #endif
653
654 #ifdef __APPLE__
655 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
656 // Additional thread_id used to correlate threads in SA
657 thread_identifier_info_data_t m_ident_info;
658 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
659
660 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
661 (thread_info_t) &m_ident_info, &count);
662
663 return m_ident_info.thread_id;
664 }
665 #endif
666
667 // Thread start routine for all newly created threads
668 static void *java_start(Thread *thread) {
669 // Try to randomize the cache line index of hot stack frames.
670 // This helps when threads of the same stack traces evict each other's
671 // cache lines. The threads can be either from the same JVM instance, or
672 // from different JVM instances. The benefit is especially true for
673 // processors with hyperthreading technology.
674 static int counter = 0;
675 int pid = os::current_process_id();
676 alloca(((pid ^ counter++) & 7) * 128);
677
678 thread->initialize_thread_current();
679
680 OSThread* osthread = thread->osthread();
681 Monitor* sync = osthread->startThread_lock();
682
683 osthread->set_thread_id(os::Bsd::gettid());
684
685 log_debug(os)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ".",
686 os::current_thread_id(), (uintx) pthread_self());
687
688 #ifdef __APPLE__
689 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
690 guarantee(unique_thread_id != 0, "unique thread id was not found");
691 osthread->set_unique_thread_id(unique_thread_id);
692 #endif
693 // initialize signal mask for this thread
694 os::Bsd::hotspot_sigmask(thread);
695
696 // initialize floating point control register
697 os::Bsd::init_thread_fpu_state();
698
699 #ifdef __APPLE__
700 // register thread with objc gc
701 if (objc_registerThreadWithCollectorFunction != NULL) {
702 objc_registerThreadWithCollectorFunction();
703 }
704 #endif
705
706 // handshaking with parent thread
707 {
708 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
709
710 // notify parent thread
711 osthread->set_state(INITIALIZED);
712 sync->notify_all();
713
714 // wait until os::start_thread()
715 while (osthread->get_state() == INITIALIZED) {
716 sync->wait(Mutex::_no_safepoint_check_flag);
717 }
718 }
719
720 // call one more level start routine
721 thread->run();
722
723 log_debug(os)("Thread finished (tid " UINTX_FORMAT ", pthread id " UINTX_FORMAT ").",
724 os::current_thread_id(), (uintx) pthread_self());
725
726 return 0;
727 }
728
729 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
730 assert(thread->osthread() == NULL, "caller responsible");
731
732 // Allocate the OSThread object
733 OSThread* osthread = new OSThread(NULL, NULL);
734 if (osthread == NULL) {
735 return false;
736 }
737
738 // set the correct thread state
739 osthread->set_thread_type(thr_type);
740
741 // Initial state is ALLOCATED but not INITIALIZED
742 osthread->set_state(ALLOCATED);
743
744 thread->set_osthread(osthread);
745
746 // init thread attributes
747 pthread_attr_t attr;
748 pthread_attr_init(&attr);
749 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
750
751 // calculate stack size if it's not specified by caller
752 if (stack_size == 0) {
753 stack_size = os::Bsd::default_stack_size(thr_type);
754
755 switch (thr_type) {
756 case os::java_thread:
757 // Java threads use ThreadStackSize which default value can be
758 // changed with the flag -Xss
759 assert(JavaThread::stack_size_at_create() > 0, "this should be set");
760 stack_size = JavaThread::stack_size_at_create();
761 break;
762 case os::compiler_thread:
763 if (CompilerThreadStackSize > 0) {
764 stack_size = (size_t)(CompilerThreadStackSize * K);
765 break;
766 } // else fall through:
767 // use VMThreadStackSize if CompilerThreadStackSize is not defined
768 case os::vm_thread:
769 case os::pgc_thread:
770 case os::cgc_thread:
771 case os::watcher_thread:
772 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
773 break;
774 }
775 }
776
777 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
778 pthread_attr_setstacksize(&attr, stack_size);
779
780 ThreadState state;
781
782 {
783 pthread_t tid;
784 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
785
786 LogHandle(os) log;
787 if (log.is_debug()) {
788 char buf[64];
789 if (ret == 0) {
790 log.debug("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
791 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
792 } else {
793 log.warning("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
794 os::errno_name(errno), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
795 }
796 }
797
798 pthread_attr_destroy(&attr);
799
800 if (ret != 0) {
801 // Need to clean up stuff we've allocated so far
802 thread->set_osthread(NULL);
803 delete osthread;
804 return false;
805 }
806
807 // Store pthread info into the OSThread
808 osthread->set_pthread_id(tid);
809
810 // Wait until child thread is either initialized or aborted
811 {
812 Monitor* sync_with_child = osthread->startThread_lock();
813 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
814 while ((state = osthread->get_state()) == ALLOCATED) {
815 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
816 }
817 }
818
819 }
820
821 // Aborted due to thread limit being reached
822 if (state == ZOMBIE) {
823 thread->set_osthread(NULL);
824 delete osthread;
825 return false;
826 }
827
828 // The thread is returned suspended (in state INITIALIZED),
829 // and is started higher up in the call chain
830 assert(state == INITIALIZED, "race condition");
831 return true;
832 }
833
834 /////////////////////////////////////////////////////////////////////////////
835 // attach existing thread
836
837 // bootstrap the main thread
838 bool os::create_main_thread(JavaThread* thread) {
839 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
840 return create_attached_thread(thread);
841 }
842
843 bool os::create_attached_thread(JavaThread* thread) {
844 #ifdef ASSERT
845 thread->verify_not_published();
846 #endif
847
848 // Allocate the OSThread object
849 OSThread* osthread = new OSThread(NULL, NULL);
850
851 if (osthread == NULL) {
852 return false;
853 }
854
855 osthread->set_thread_id(os::Bsd::gettid());
856
857 // Store pthread info into the OSThread
858 #ifdef __APPLE__
859 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
860 guarantee(unique_thread_id != 0, "just checking");
861 osthread->set_unique_thread_id(unique_thread_id);
862 #endif
863 osthread->set_pthread_id(::pthread_self());
864
865 // initialize floating point control register
866 os::Bsd::init_thread_fpu_state();
867
868 // Initial thread state is RUNNABLE
869 osthread->set_state(RUNNABLE);
870
871 thread->set_osthread(osthread);
872
873 // initialize signal mask for this thread
874 // and save the caller's signal mask
875 os::Bsd::hotspot_sigmask(thread);
876
877 log_debug(os)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ".",
878 os::current_thread_id(), (uintx) pthread_self());
879
880 return true;
881 }
882
883 void os::pd_start_thread(Thread* thread) {
884 OSThread * osthread = thread->osthread();
885 assert(osthread->get_state() != INITIALIZED, "just checking");
886 Monitor* sync_with_child = osthread->startThread_lock();
887 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
888 sync_with_child->notify();
889 }
890
891 // Free Bsd resources related to the OSThread
892 void os::free_thread(OSThread* osthread) {
893 assert(osthread != NULL, "osthread not set");
894
895 if (Thread::current()->osthread() == osthread) {
896 // Restore caller's signal mask
897 sigset_t sigmask = osthread->caller_sigmask();
898 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
899 }
900
901 delete osthread;
902 }
903
904 ////////////////////////////////////////////////////////////////////////////////
905 // time support
906
907 // Time since start-up in seconds to a fine granularity.
908 // Used by VMSelfDestructTimer and the MemProfiler.
909 double os::elapsedTime() {
910
911 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
912 }
913
914 jlong os::elapsed_counter() {
915 return javaTimeNanos() - initial_time_count;
916 }
917
918 jlong os::elapsed_frequency() {
919 return NANOSECS_PER_SEC; // nanosecond resolution
920 }
921
922 bool os::supports_vtime() { return true; }
923 bool os::enable_vtime() { return false; }
924 bool os::vtime_enabled() { return false; }
925
926 double os::elapsedVTime() {
927 // better than nothing, but not much
928 return elapsedTime();
929 }
930
931 jlong os::javaTimeMillis() {
932 timeval time;
933 int status = gettimeofday(&time, NULL);
934 assert(status != -1, "bsd error");
935 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
936 }
937
938 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
939 timeval time;
940 int status = gettimeofday(&time, NULL);
941 assert(status != -1, "bsd error");
942 seconds = jlong(time.tv_sec);
943 nanos = jlong(time.tv_usec) * 1000;
944 }
945
946 #ifndef __APPLE__
947 #ifndef CLOCK_MONOTONIC
948 #define CLOCK_MONOTONIC (1)
949 #endif
950 #endif
951
952 #ifdef __APPLE__
953 void os::Bsd::clock_init() {
954 mach_timebase_info(&_timebase_info);
955 }
956 #else
957 void os::Bsd::clock_init() {
958 struct timespec res;
959 struct timespec tp;
960 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
961 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
962 // yes, monotonic clock is supported
963 _clock_gettime = ::clock_gettime;
964 }
965 }
966 #endif
967
968
969
970 #ifdef __APPLE__
971
972 jlong os::javaTimeNanos() {
973 const uint64_t tm = mach_absolute_time();
974 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
975 const uint64_t prev = Bsd::_max_abstime;
976 if (now <= prev) {
977 return prev; // same or retrograde time;
978 }
979 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
980 assert(obsv >= prev, "invariant"); // Monotonicity
981 // If the CAS succeeded then we're done and return "now".
982 // If the CAS failed and the observed value "obsv" is >= now then
983 // we should return "obsv". If the CAS failed and now > obsv > prv then
984 // some other thread raced this thread and installed a new value, in which case
985 // we could either (a) retry the entire operation, (b) retry trying to install now
986 // or (c) just return obsv. We use (c). No loop is required although in some cases
987 // we might discard a higher "now" value in deference to a slightly lower but freshly
988 // installed obsv value. That's entirely benign -- it admits no new orderings compared
989 // to (a) or (b) -- and greatly reduces coherence traffic.
990 // We might also condition (c) on the magnitude of the delta between obsv and now.
991 // Avoiding excessive CAS operations to hot RW locations is critical.
992 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
993 return (prev == obsv) ? now : obsv;
994 }
995
996 #else // __APPLE__
997
998 jlong os::javaTimeNanos() {
999 if (os::supports_monotonic_clock()) {
1000 struct timespec tp;
1001 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1002 assert(status == 0, "gettime error");
1003 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1004 return result;
1005 } else {
1006 timeval time;
1007 int status = gettimeofday(&time, NULL);
1008 assert(status != -1, "bsd error");
1009 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1010 return 1000 * usecs;
1011 }
1012 }
1013
1014 #endif // __APPLE__
1015
1016 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1017 if (os::supports_monotonic_clock()) {
1018 info_ptr->max_value = ALL_64_BITS;
1019
1020 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1021 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1022 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1023 } else {
1024 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1025 info_ptr->max_value = ALL_64_BITS;
1026
1027 // gettimeofday is a real time clock so it skips
1028 info_ptr->may_skip_backward = true;
1029 info_ptr->may_skip_forward = true;
1030 }
1031
1032 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1033 }
1034
1035 // Return the real, user, and system times in seconds from an
1036 // arbitrary fixed point in the past.
1037 bool os::getTimesSecs(double* process_real_time,
1038 double* process_user_time,
1039 double* process_system_time) {
1040 struct tms ticks;
1041 clock_t real_ticks = times(&ticks);
1042
1043 if (real_ticks == (clock_t) (-1)) {
1044 return false;
1045 } else {
1046 double ticks_per_second = (double) clock_tics_per_sec;
1047 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1048 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1049 *process_real_time = ((double) real_ticks) / ticks_per_second;
1050
1051 return true;
1052 }
1053 }
1054
1055
1056 char * os::local_time_string(char *buf, size_t buflen) {
1057 struct tm t;
1058 time_t long_time;
1059 time(&long_time);
1060 localtime_r(&long_time, &t);
1061 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1062 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1063 t.tm_hour, t.tm_min, t.tm_sec);
1064 return buf;
1065 }
1066
1067 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1068 return localtime_r(clock, res);
1069 }
1070
1071 ////////////////////////////////////////////////////////////////////////////////
1072 // runtime exit support
1073
1074 // Note: os::shutdown() might be called very early during initialization, or
1075 // called from signal handler. Before adding something to os::shutdown(), make
1076 // sure it is async-safe and can handle partially initialized VM.
1077 void os::shutdown() {
1078
1079 // allow PerfMemory to attempt cleanup of any persistent resources
1080 perfMemory_exit();
1081
1082 // needs to remove object in file system
1083 AttachListener::abort();
1084
1085 // flush buffered output, finish log files
1086 ostream_abort();
1087
1088 // Check for abort hook
1089 abort_hook_t abort_hook = Arguments::abort_hook();
1090 if (abort_hook != NULL) {
1091 abort_hook();
1092 }
1093
1094 }
1095
1096 // Note: os::abort() might be called very early during initialization, or
1097 // called from signal handler. Before adding something to os::abort(), make
1098 // sure it is async-safe and can handle partially initialized VM.
1099 void os::abort(bool dump_core, void* siginfo, const void* context) {
1100 os::shutdown();
1101 if (dump_core) {
1102 #ifndef PRODUCT
1103 fdStream out(defaultStream::output_fd());
1104 out.print_raw("Current thread is ");
1105 char buf[16];
1106 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1107 out.print_raw_cr(buf);
1108 out.print_raw_cr("Dumping core ...");
1109 #endif
1110 ::abort(); // dump core
1111 }
1112
1113 ::exit(1);
1114 }
1115
1116 // Die immediately, no exit hook, no abort hook, no cleanup.
1117 void os::die() {
1118 // _exit() on BsdThreads only kills current thread
1119 ::abort();
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 if (errno == 0) return 0;
1127
1128 const char *s = ::strerror(errno);
1129 size_t n = ::strlen(s);
1130 if (n >= len) {
1131 n = len - 1;
1132 }
1133 ::strncpy(buf, s, n);
1134 buf[n] = '\0';
1135 return n;
1136 }
1137
1138 // Information of current thread in variety of formats
1139 pid_t os::Bsd::gettid() {
1140 int retval = -1;
1141
1142 #ifdef __APPLE__ //XNU kernel
1143 // despite the fact mach port is actually not a thread id use it
1144 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1145 retval = ::pthread_mach_thread_np(::pthread_self());
1146 guarantee(retval != 0, "just checking");
1147 return retval;
1148
1149 #else
1150 #ifdef __FreeBSD__
1151 retval = syscall(SYS_thr_self);
1152 #else
1153 #ifdef __OpenBSD__
1154 retval = syscall(SYS_getthrid);
1155 #else
1156 #ifdef __NetBSD__
1157 retval = (pid_t) syscall(SYS__lwp_self);
1158 #endif
1159 #endif
1160 #endif
1161 #endif
1162
1163 if (retval == -1) {
1164 return getpid();
1165 }
1166 }
1167
1168 intx os::current_thread_id() {
1169 #ifdef __APPLE__
1170 return (intx)::pthread_mach_thread_np(::pthread_self());
1171 #else
1172 return (intx)::pthread_self();
1173 #endif
1174 }
1175
1176 int os::current_process_id() {
1177
1178 // Under the old bsd thread library, bsd gives each thread
1179 // its own process id. Because of this each thread will return
1180 // a different pid if this method were to return the result
1181 // of getpid(2). Bsd provides no api that returns the pid
1182 // of the launcher thread for the vm. This implementation
1183 // returns a unique pid, the pid of the launcher thread
1184 // that starts the vm 'process'.
1185
1186 // Under the NPTL, getpid() returns the same pid as the
1187 // launcher thread rather than a unique pid per thread.
1188 // Use gettid() if you want the old pre NPTL behaviour.
1189
1190 // if you are looking for the result of a call to getpid() that
1191 // returns a unique pid for the calling thread, then look at the
1192 // OSThread::thread_id() method in osThread_bsd.hpp file
1193
1194 return (int)(_initial_pid ? _initial_pid : getpid());
1195 }
1196
1197 // DLL functions
1198
1199 #define JNI_LIB_PREFIX "lib"
1200 #ifdef __APPLE__
1201 #define JNI_LIB_SUFFIX ".dylib"
1202 #else
1203 #define JNI_LIB_SUFFIX ".so"
1204 #endif
1205
1206 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1207
1208 // This must be hard coded because it's the system's temporary
1209 // directory not the java application's temp directory, ala java.io.tmpdir.
1210 #ifdef __APPLE__
1211 // macosx has a secure per-user temporary directory
1212 char temp_path_storage[PATH_MAX];
1213 const char* os::get_temp_directory() {
1214 static char *temp_path = NULL;
1215 if (temp_path == NULL) {
1216 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1217 if (pathSize == 0 || pathSize > PATH_MAX) {
1218 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1219 }
1220 temp_path = temp_path_storage;
1221 }
1222 return temp_path;
1223 }
1224 #else // __APPLE__
1225 const char* os::get_temp_directory() { return "/tmp"; }
1226 #endif // __APPLE__
1227
1228 static bool file_exists(const char* filename) {
1229 struct stat statbuf;
1230 if (filename == NULL || strlen(filename) == 0) {
1231 return false;
1232 }
1233 return os::stat(filename, &statbuf) == 0;
1234 }
1235
1236 bool os::dll_build_name(char* buffer, size_t buflen,
1237 const char* pname, const char* fname) {
1238 bool retval = false;
1239 // Copied from libhpi
1240 const size_t pnamelen = pname ? strlen(pname) : 0;
1241
1242 // Return error on buffer overflow.
1243 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1244 return retval;
1245 }
1246
1247 if (pnamelen == 0) {
1248 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1249 retval = true;
1250 } else if (strchr(pname, *os::path_separator()) != NULL) {
1251 int n;
1252 char** pelements = split_path(pname, &n);
1253 if (pelements == NULL) {
1254 return false;
1255 }
1256 for (int i = 0; i < n; i++) {
1257 // Really shouldn't be NULL, but check can't hurt
1258 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1259 continue; // skip the empty path values
1260 }
1261 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1262 pelements[i], fname);
1263 if (file_exists(buffer)) {
1264 retval = true;
1265 break;
1266 }
1267 }
1268 // release the storage
1269 for (int i = 0; i < n; i++) {
1270 if (pelements[i] != NULL) {
1271 FREE_C_HEAP_ARRAY(char, pelements[i]);
1272 }
1273 }
1274 if (pelements != NULL) {
1275 FREE_C_HEAP_ARRAY(char*, pelements);
1276 }
1277 } else {
1278 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1279 retval = true;
1280 }
1281 return retval;
1282 }
1283
1284 // check if addr is inside libjvm.so
1285 bool os::address_is_in_vm(address addr) {
1286 static address libjvm_base_addr;
1287 Dl_info dlinfo;
1288
1289 if (libjvm_base_addr == NULL) {
1290 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1291 libjvm_base_addr = (address)dlinfo.dli_fbase;
1292 }
1293 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1294 }
1295
1296 if (dladdr((void *)addr, &dlinfo) != 0) {
1297 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1298 }
1299
1300 return false;
1301 }
1302
1303
1304 #define MACH_MAXSYMLEN 256
1305
1306 bool os::dll_address_to_function_name(address addr, char *buf,
1307 int buflen, int *offset,
1308 bool demangle) {
1309 // buf is not optional, but offset is optional
1310 assert(buf != NULL, "sanity check");
1311
1312 Dl_info dlinfo;
1313 char localbuf[MACH_MAXSYMLEN];
1314
1315 if (dladdr((void*)addr, &dlinfo) != 0) {
1316 // see if we have a matching symbol
1317 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1318 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1319 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1320 }
1321 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1322 return true;
1323 }
1324 // no matching symbol so try for just file info
1325 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1326 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1327 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1328 return true;
1329 }
1330 }
1331
1332 // Handle non-dynamic manually:
1333 if (dlinfo.dli_fbase != NULL &&
1334 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1335 dlinfo.dli_fbase)) {
1336 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1337 jio_snprintf(buf, buflen, "%s", localbuf);
1338 }
1339 return true;
1340 }
1341 }
1342 buf[0] = '\0';
1343 if (offset != NULL) *offset = -1;
1344 return false;
1345 }
1346
1347 // ported from solaris version
1348 bool os::dll_address_to_library_name(address addr, char* buf,
1349 int buflen, int* offset) {
1350 // buf is not optional, but offset is optional
1351 assert(buf != NULL, "sanity check");
1352
1353 Dl_info dlinfo;
1354
1355 if (dladdr((void*)addr, &dlinfo) != 0) {
1356 if (dlinfo.dli_fname != NULL) {
1357 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1358 }
1359 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1360 *offset = addr - (address)dlinfo.dli_fbase;
1361 }
1362 return true;
1363 }
1364
1365 buf[0] = '\0';
1366 if (offset) *offset = -1;
1367 return false;
1368 }
1369
1370 // Loads .dll/.so and
1371 // in case of error it checks if .dll/.so was built for the
1372 // same architecture as Hotspot is running on
1373
1374 #ifdef __APPLE__
1375 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1376 #ifdef STATIC_BUILD
1377 return os::get_default_process_handle();
1378 #else
1379 void * result= ::dlopen(filename, RTLD_LAZY);
1380 if (result != NULL) {
1381 // Successful loading
1382 return result;
1383 }
1384
1385 // Read system error message into ebuf
1386 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1387 ebuf[ebuflen-1]='\0';
1388
1389 return NULL;
1390 #endif // STATIC_BUILD
1391 }
1392 #else
1393 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1394 #ifdef STATIC_BUILD
1395 return os::get_default_process_handle();
1396 #else
1397 void * result= ::dlopen(filename, RTLD_LAZY);
1398 if (result != NULL) {
1399 // Successful loading
1400 return result;
1401 }
1402
1403 Elf32_Ehdr elf_head;
1404
1405 // Read system error message into ebuf
1406 // It may or may not be overwritten below
1407 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1408 ebuf[ebuflen-1]='\0';
1409 int diag_msg_max_length=ebuflen-strlen(ebuf);
1410 char* diag_msg_buf=ebuf+strlen(ebuf);
1411
1412 if (diag_msg_max_length==0) {
1413 // No more space in ebuf for additional diagnostics message
1414 return NULL;
1415 }
1416
1417
1418 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1419
1420 if (file_descriptor < 0) {
1421 // Can't open library, report dlerror() message
1422 return NULL;
1423 }
1424
1425 bool failed_to_read_elf_head=
1426 (sizeof(elf_head)!=
1427 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1428
1429 ::close(file_descriptor);
1430 if (failed_to_read_elf_head) {
1431 // file i/o error - report dlerror() msg
1432 return NULL;
1433 }
1434
1435 typedef struct {
1436 Elf32_Half code; // Actual value as defined in elf.h
1437 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1438 char elf_class; // 32 or 64 bit
1439 char endianess; // MSB or LSB
1440 char* name; // String representation
1441 } arch_t;
1442
1443 #ifndef EM_486
1444 #define EM_486 6 /* Intel 80486 */
1445 #endif
1446
1447 #ifndef EM_MIPS_RS3_LE
1448 #define EM_MIPS_RS3_LE 10 /* MIPS */
1449 #endif
1450
1451 #ifndef EM_PPC64
1452 #define EM_PPC64 21 /* PowerPC64 */
1453 #endif
1454
1455 #ifndef EM_S390
1456 #define EM_S390 22 /* IBM System/390 */
1457 #endif
1458
1459 #ifndef EM_IA_64
1460 #define EM_IA_64 50 /* HP/Intel IA-64 */
1461 #endif
1462
1463 #ifndef EM_X86_64
1464 #define EM_X86_64 62 /* AMD x86-64 */
1465 #endif
1466
1467 static const arch_t arch_array[]={
1468 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1469 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1470 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1471 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1472 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1473 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1474 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1475 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1476 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1477 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1478 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1479 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1480 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1481 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1482 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1483 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1484 };
1485
1486 #if (defined IA32)
1487 static Elf32_Half running_arch_code=EM_386;
1488 #elif (defined AMD64)
1489 static Elf32_Half running_arch_code=EM_X86_64;
1490 #elif (defined IA64)
1491 static Elf32_Half running_arch_code=EM_IA_64;
1492 #elif (defined __sparc) && (defined _LP64)
1493 static Elf32_Half running_arch_code=EM_SPARCV9;
1494 #elif (defined __sparc) && (!defined _LP64)
1495 static Elf32_Half running_arch_code=EM_SPARC;
1496 #elif (defined __powerpc64__)
1497 static Elf32_Half running_arch_code=EM_PPC64;
1498 #elif (defined __powerpc__)
1499 static Elf32_Half running_arch_code=EM_PPC;
1500 #elif (defined ARM)
1501 static Elf32_Half running_arch_code=EM_ARM;
1502 #elif (defined S390)
1503 static Elf32_Half running_arch_code=EM_S390;
1504 #elif (defined ALPHA)
1505 static Elf32_Half running_arch_code=EM_ALPHA;
1506 #elif (defined MIPSEL)
1507 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1508 #elif (defined PARISC)
1509 static Elf32_Half running_arch_code=EM_PARISC;
1510 #elif (defined MIPS)
1511 static Elf32_Half running_arch_code=EM_MIPS;
1512 #elif (defined M68K)
1513 static Elf32_Half running_arch_code=EM_68K;
1514 #else
1515 #error Method os::dll_load requires that one of following is defined:\
1516 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1517 #endif
1518
1519 // Identify compatability class for VM's architecture and library's architecture
1520 // Obtain string descriptions for architectures
1521
1522 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1523 int running_arch_index=-1;
1524
1525 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1526 if (running_arch_code == arch_array[i].code) {
1527 running_arch_index = i;
1528 }
1529 if (lib_arch.code == arch_array[i].code) {
1530 lib_arch.compat_class = arch_array[i].compat_class;
1531 lib_arch.name = arch_array[i].name;
1532 }
1533 }
1534
1535 assert(running_arch_index != -1,
1536 "Didn't find running architecture code (running_arch_code) in arch_array");
1537 if (running_arch_index == -1) {
1538 // Even though running architecture detection failed
1539 // we may still continue with reporting dlerror() message
1540 return NULL;
1541 }
1542
1543 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1544 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1545 return NULL;
1546 }
1547
1548 #ifndef S390
1549 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1550 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1551 return NULL;
1552 }
1553 #endif // !S390
1554
1555 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1556 if (lib_arch.name!=NULL) {
1557 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1558 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1559 lib_arch.name, arch_array[running_arch_index].name);
1560 } else {
1561 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1562 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1563 lib_arch.code,
1564 arch_array[running_arch_index].name);
1565 }
1566 }
1567
1568 return NULL;
1569 #endif // STATIC_BUILD
1570 }
1571 #endif // !__APPLE__
1572
1573 void* os::get_default_process_handle() {
1574 #ifdef __APPLE__
1575 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1576 // to avoid finding unexpected symbols on second (or later)
1577 // loads of a library.
1578 return (void*)::dlopen(NULL, RTLD_FIRST);
1579 #else
1580 return (void*)::dlopen(NULL, RTLD_LAZY);
1581 #endif
1582 }
1583
1584 // XXX: Do we need a lock around this as per Linux?
1585 void* os::dll_lookup(void* handle, const char* name) {
1586 return dlsym(handle, name);
1587 }
1588
1589 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1590 outputStream * out = (outputStream *) param;
1591 out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1592 return 0;
1593 }
1594
1595 void os::print_dll_info(outputStream *st) {
1596 st->print_cr("Dynamic libraries:");
1597 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1598 st->print_cr("Error: Cannot print dynamic libraries.");
1599 }
1600 }
1601
1602 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1603 #ifdef RTLD_DI_LINKMAP
1604 Dl_info dli;
1605 void *handle;
1606 Link_map *map;
1607 Link_map *p;
1608
1609 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1610 dli.dli_fname == NULL) {
1611 return 1;
1612 }
1613 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1614 if (handle == NULL) {
1615 return 1;
1616 }
1617 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1618 if (map == NULL) {
1619 dlclose(handle);
1620 return 1;
1621 }
1622
1623 while (map->l_prev != NULL)
1624 map = map->l_prev;
1625
1626 while (map != NULL) {
1627 // Value for top_address is returned as 0 since we don't have any information about module size
1628 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1629 dlclose(handle);
1630 return 1;
1631 }
1632 map = map->l_next;
1633 }
1634
1635 dlclose(handle);
1636 #elif defined(__APPLE__)
1637 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1638 // Value for top_address is returned as 0 since we don't have any information about module size
1639 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1640 return 1;
1641 }
1642 }
1643 return 0;
1644 #else
1645 return 1;
1646 #endif
1647 }
1648
1649 void os::get_summary_os_info(char* buf, size_t buflen) {
1650 // These buffers are small because we want this to be brief
1651 // and not use a lot of stack while generating the hs_err file.
1652 char os[100];
1653 size_t size = sizeof(os);
1654 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1655 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1656 #ifdef __APPLE__
1657 strncpy(os, "Darwin", sizeof(os));
1658 #elif __OpenBSD__
1659 strncpy(os, "OpenBSD", sizeof(os));
1660 #else
1661 strncpy(os, "BSD", sizeof(os));
1662 #endif
1663 }
1664
1665 char release[100];
1666 size = sizeof(release);
1667 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1668 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1669 // if error, leave blank
1670 strncpy(release, "", sizeof(release));
1671 }
1672 snprintf(buf, buflen, "%s %s", os, release);
1673 }
1674
1675 void os::print_os_info_brief(outputStream* st) {
1676 os::Posix::print_uname_info(st);
1677 }
1678
1679 void os::print_os_info(outputStream* st) {
1680 st->print("OS:");
1681
1682 os::Posix::print_uname_info(st);
1683
1684 os::Posix::print_rlimit_info(st);
1685
1686 os::Posix::print_load_average(st);
1687 }
1688
1689 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1690 // Nothing to do for now.
1691 }
1692
1693 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1694 unsigned int mhz;
1695 size_t size = sizeof(mhz);
1696 int mib[] = { CTL_HW, HW_CPU_FREQ };
1697 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1698 mhz = 1; // looks like an error but can be divided by
1699 } else {
1700 mhz /= 1000000; // reported in millions
1701 }
1702
1703 char model[100];
1704 size = sizeof(model);
1705 int mib_model[] = { CTL_HW, HW_MODEL };
1706 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1707 strncpy(model, cpu_arch, sizeof(model));
1708 }
1709
1710 char machine[100];
1711 size = sizeof(machine);
1712 int mib_machine[] = { CTL_HW, HW_MACHINE };
1713 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1714 strncpy(machine, "", sizeof(machine));
1715 }
1716
1717 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1718 }
1719
1720 void os::print_memory_info(outputStream* st) {
1721
1722 st->print("Memory:");
1723 st->print(" %dk page", os::vm_page_size()>>10);
1724
1725 st->print(", physical " UINT64_FORMAT "k",
1726 os::physical_memory() >> 10);
1727 st->print("(" UINT64_FORMAT "k free)",
1728 os::available_memory() >> 10);
1729 st->cr();
1730 }
1731
1732 static void print_signal_handler(outputStream* st, int sig,
1733 char* buf, size_t buflen);
1734
1735 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1736 st->print_cr("Signal Handlers:");
1737 print_signal_handler(st, SIGSEGV, buf, buflen);
1738 print_signal_handler(st, SIGBUS , buf, buflen);
1739 print_signal_handler(st, SIGFPE , buf, buflen);
1740 print_signal_handler(st, SIGPIPE, buf, buflen);
1741 print_signal_handler(st, SIGXFSZ, buf, buflen);
1742 print_signal_handler(st, SIGILL , buf, buflen);
1743 print_signal_handler(st, SR_signum, buf, buflen);
1744 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1745 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1746 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1747 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1748 }
1749
1750 static char saved_jvm_path[MAXPATHLEN] = {0};
1751
1752 // Find the full path to the current module, libjvm
1753 void os::jvm_path(char *buf, jint buflen) {
1754 // Error checking.
1755 if (buflen < MAXPATHLEN) {
1756 assert(false, "must use a large-enough buffer");
1757 buf[0] = '\0';
1758 return;
1759 }
1760 // Lazy resolve the path to current module.
1761 if (saved_jvm_path[0] != 0) {
1762 strcpy(buf, saved_jvm_path);
1763 return;
1764 }
1765
1766 char dli_fname[MAXPATHLEN];
1767 bool ret = dll_address_to_library_name(
1768 CAST_FROM_FN_PTR(address, os::jvm_path),
1769 dli_fname, sizeof(dli_fname), NULL);
1770 assert(ret, "cannot locate libjvm");
1771 char *rp = NULL;
1772 if (ret && dli_fname[0] != '\0') {
1773 rp = realpath(dli_fname, buf);
1774 }
1775 if (rp == NULL) {
1776 return;
1777 }
1778
1779 if (Arguments::sun_java_launcher_is_altjvm()) {
1780 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1781 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1782 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1783 // appears at the right place in the string, then assume we are
1784 // installed in a JDK and we're done. Otherwise, check for a
1785 // JAVA_HOME environment variable and construct a path to the JVM
1786 // being overridden.
1787
1788 const char *p = buf + strlen(buf) - 1;
1789 for (int count = 0; p > buf && count < 5; ++count) {
1790 for (--p; p > buf && *p != '/'; --p)
1791 /* empty */ ;
1792 }
1793
1794 if (strncmp(p, "/jre/lib/", 9) != 0) {
1795 // Look for JAVA_HOME in the environment.
1796 char* java_home_var = ::getenv("JAVA_HOME");
1797 if (java_home_var != NULL && java_home_var[0] != 0) {
1798 char* jrelib_p;
1799 int len;
1800
1801 // Check the current module name "libjvm"
1802 p = strrchr(buf, '/');
1803 assert(strstr(p, "/libjvm") == p, "invalid library name");
1804
1805 rp = realpath(java_home_var, buf);
1806 if (rp == NULL) {
1807 return;
1808 }
1809
1810 // determine if this is a legacy image or modules image
1811 // modules image doesn't have "jre" subdirectory
1812 len = strlen(buf);
1813 assert(len < buflen, "Ran out of buffer space");
1814 jrelib_p = buf + len;
1815
1816 // Add the appropriate library subdir
1817 snprintf(jrelib_p, buflen-len, "/jre/lib");
1818 if (0 != access(buf, F_OK)) {
1819 snprintf(jrelib_p, buflen-len, "/lib");
1820 }
1821
1822 // Add the appropriate client or server subdir
1823 len = strlen(buf);
1824 jrelib_p = buf + len;
1825 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1826 if (0 != access(buf, F_OK)) {
1827 snprintf(jrelib_p, buflen-len, "%s", "");
1828 }
1829
1830 // If the path exists within JAVA_HOME, add the JVM library name
1831 // to complete the path to JVM being overridden. Otherwise fallback
1832 // to the path to the current library.
1833 if (0 == access(buf, F_OK)) {
1834 // Use current module name "libjvm"
1835 len = strlen(buf);
1836 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1837 } else {
1838 // Fall back to path of current library
1839 rp = realpath(dli_fname, buf);
1840 if (rp == NULL) {
1841 return;
1842 }
1843 }
1844 }
1845 }
1846 }
1847
1848 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1849 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1850 }
1851
1852 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1853 // no prefix required, not even "_"
1854 }
1855
1856 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1857 // no suffix required
1858 }
1859
1860 ////////////////////////////////////////////////////////////////////////////////
1861 // sun.misc.Signal support
1862
1863 static volatile jint sigint_count = 0;
1864
1865 static void UserHandler(int sig, void *siginfo, void *context) {
1866 // 4511530 - sem_post is serialized and handled by the manager thread. When
1867 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1868 // don't want to flood the manager thread with sem_post requests.
1869 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1870 return;
1871 }
1872
1873 // Ctrl-C is pressed during error reporting, likely because the error
1874 // handler fails to abort. Let VM die immediately.
1875 if (sig == SIGINT && is_error_reported()) {
1876 os::die();
1877 }
1878
1879 os::signal_notify(sig);
1880 }
1881
1882 void* os::user_handler() {
1883 return CAST_FROM_FN_PTR(void*, UserHandler);
1884 }
1885
1886 extern "C" {
1887 typedef void (*sa_handler_t)(int);
1888 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1889 }
1890
1891 void* os::signal(int signal_number, void* handler) {
1892 struct sigaction sigAct, oldSigAct;
1893
1894 sigfillset(&(sigAct.sa_mask));
1895 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1896 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1897
1898 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1899 // -1 means registration failed
1900 return (void *)-1;
1901 }
1902
1903 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1904 }
1905
1906 void os::signal_raise(int signal_number) {
1907 ::raise(signal_number);
1908 }
1909
1910 // The following code is moved from os.cpp for making this
1911 // code platform specific, which it is by its very nature.
1912
1913 // Will be modified when max signal is changed to be dynamic
1914 int os::sigexitnum_pd() {
1915 return NSIG;
1916 }
1917
1918 // a counter for each possible signal value
1919 static volatile jint pending_signals[NSIG+1] = { 0 };
1920
1921 // Bsd(POSIX) specific hand shaking semaphore.
1922 #ifdef __APPLE__
1923 typedef semaphore_t os_semaphore_t;
1924
1925 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1926 #define SEM_WAIT(sem) semaphore_wait(sem)
1927 #define SEM_POST(sem) semaphore_signal(sem)
1928 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1929 #else
1930 typedef sem_t os_semaphore_t;
1931
1932 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1933 #define SEM_WAIT(sem) sem_wait(&sem)
1934 #define SEM_POST(sem) sem_post(&sem)
1935 #define SEM_DESTROY(sem) sem_destroy(&sem)
1936 #endif
1937
1938 #ifdef __APPLE__
1939 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
1940
1941 static const char* sem_init_strerror(kern_return_t value) {
1942 switch (value) {
1943 case KERN_INVALID_ARGUMENT: return "Invalid argument";
1944 case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
1945 default: return "Unknown";
1946 }
1947 }
1948
1949 OSXSemaphore::OSXSemaphore(uint value) {
1950 kern_return_t ret = SEM_INIT(_semaphore, value);
1951
1952 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
1953 }
1954
1955 OSXSemaphore::~OSXSemaphore() {
1956 SEM_DESTROY(_semaphore);
1957 }
1958
1959 void OSXSemaphore::signal(uint count) {
1960 for (uint i = 0; i < count; i++) {
1961 kern_return_t ret = SEM_POST(_semaphore);
1962
1963 assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
1964 }
1965 }
1966
1967 void OSXSemaphore::wait() {
1968 kern_return_t ret;
1969 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
1970 // Semaphore was interrupted. Retry.
1971 }
1972 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
1973 }
1974
1975 jlong OSXSemaphore::currenttime() {
1976 struct timeval tv;
1977 gettimeofday(&tv, NULL);
1978 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1979 }
1980
1981 bool OSXSemaphore::trywait() {
1982 return timedwait(0, 0);
1983 }
1984
1985 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
1986 kern_return_t kr = KERN_ABORTED;
1987 mach_timespec_t waitspec;
1988 waitspec.tv_sec = sec;
1989 waitspec.tv_nsec = nsec;
1990
1991 jlong starttime = currenttime();
1992
1993 kr = semaphore_timedwait(_semaphore, waitspec);
1994 while (kr == KERN_ABORTED) {
1995 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1996
1997 jlong current = currenttime();
1998 jlong passedtime = current - starttime;
1999
2000 if (passedtime >= totalwait) {
2001 waitspec.tv_sec = 0;
2002 waitspec.tv_nsec = 0;
2003 } else {
2004 jlong waittime = totalwait - (current - starttime);
2005 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2006 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2007 }
2008
2009 kr = semaphore_timedwait(_semaphore, waitspec);
2010 }
2011
2012 return kr == KERN_SUCCESS;
2013 }
2014
2015 #else
2016 // Use POSIX implementation of semaphores.
2017
2018 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
2019 struct timespec ts;
2020 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2021
2022 return ts;
2023 }
2024
2025 #endif // __APPLE__
2026
2027 static os_semaphore_t sig_sem;
2028
2029 #ifdef __APPLE__
2030 static OSXSemaphore sr_semaphore;
2031 #else
2032 static PosixSemaphore sr_semaphore;
2033 #endif
2034
2035 void os::signal_init_pd() {
2036 // Initialize signal structures
2037 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2038
2039 // Initialize signal semaphore
2040 ::SEM_INIT(sig_sem, 0);
2041 }
2042
2043 void os::signal_notify(int sig) {
2044 Atomic::inc(&pending_signals[sig]);
2045 ::SEM_POST(sig_sem);
2046 }
2047
2048 static int check_pending_signals(bool wait) {
2049 Atomic::store(0, &sigint_count);
2050 for (;;) {
2051 for (int i = 0; i < NSIG + 1; i++) {
2052 jint n = pending_signals[i];
2053 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2054 return i;
2055 }
2056 }
2057 if (!wait) {
2058 return -1;
2059 }
2060 JavaThread *thread = JavaThread::current();
2061 ThreadBlockInVM tbivm(thread);
2062
2063 bool threadIsSuspended;
2064 do {
2065 thread->set_suspend_equivalent();
2066 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2067 ::SEM_WAIT(sig_sem);
2068
2069 // were we externally suspended while we were waiting?
2070 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2071 if (threadIsSuspended) {
2072 // The semaphore has been incremented, but while we were waiting
2073 // another thread suspended us. We don't want to continue running
2074 // while suspended because that would surprise the thread that
2075 // suspended us.
2076 ::SEM_POST(sig_sem);
2077
2078 thread->java_suspend_self();
2079 }
2080 } while (threadIsSuspended);
2081 }
2082 }
2083
2084 int os::signal_lookup() {
2085 return check_pending_signals(false);
2086 }
2087
2088 int os::signal_wait() {
2089 return check_pending_signals(true);
2090 }
2091
2092 ////////////////////////////////////////////////////////////////////////////////
2093 // Virtual Memory
2094
2095 int os::vm_page_size() {
2096 // Seems redundant as all get out
2097 assert(os::Bsd::page_size() != -1, "must call os::init");
2098 return os::Bsd::page_size();
2099 }
2100
2101 // Solaris allocates memory by pages.
2102 int os::vm_allocation_granularity() {
2103 assert(os::Bsd::page_size() != -1, "must call os::init");
2104 return os::Bsd::page_size();
2105 }
2106
2107 // Rationale behind this function:
2108 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2109 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2110 // samples for JITted code. Here we create private executable mapping over the code cache
2111 // and then we can use standard (well, almost, as mapping can change) way to provide
2112 // info for the reporting script by storing timestamp and location of symbol
2113 void bsd_wrap_code(char* base, size_t size) {
2114 static volatile jint cnt = 0;
2115
2116 if (!UseOprofile) {
2117 return;
2118 }
2119
2120 char buf[PATH_MAX + 1];
2121 int num = Atomic::add(1, &cnt);
2122
2123 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2124 os::get_temp_directory(), os::current_process_id(), num);
2125 unlink(buf);
2126
2127 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2128
2129 if (fd != -1) {
2130 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2131 if (rv != (off_t)-1) {
2132 if (::write(fd, "", 1) == 1) {
2133 mmap(base, size,
2134 PROT_READ|PROT_WRITE|PROT_EXEC,
2135 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2136 }
2137 }
2138 ::close(fd);
2139 unlink(buf);
2140 }
2141 }
2142
2143 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2144 int err) {
2145 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2146 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2147 strerror(err), err);
2148 }
2149
2150 // NOTE: Bsd kernel does not really reserve the pages for us.
2151 // All it does is to check if there are enough free pages
2152 // left at the time of mmap(). This could be a potential
2153 // problem.
2154 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2155 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2156 #ifdef __OpenBSD__
2157 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2158 if (::mprotect(addr, size, prot) == 0) {
2159 return true;
2160 }
2161 #else
2162 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2163 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2164 if (res != (uintptr_t) MAP_FAILED) {
2165 return true;
2166 }
2167 #endif
2168
2169 // Warn about any commit errors we see in non-product builds just
2170 // in case mmap() doesn't work as described on the man page.
2171 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2172
2173 return false;
2174 }
2175
2176 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2177 bool exec) {
2178 // alignment_hint is ignored on this OS
2179 return pd_commit_memory(addr, size, exec);
2180 }
2181
2182 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2183 const char* mesg) {
2184 assert(mesg != NULL, "mesg must be specified");
2185 if (!pd_commit_memory(addr, size, exec)) {
2186 // add extra info in product mode for vm_exit_out_of_memory():
2187 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2188 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
2189 }
2190 }
2191
2192 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2193 size_t alignment_hint, bool exec,
2194 const char* mesg) {
2195 // alignment_hint is ignored on this OS
2196 pd_commit_memory_or_exit(addr, size, exec, mesg);
2197 }
2198
2199 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2200 }
2201
2202 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2203 ::madvise(addr, bytes, MADV_DONTNEED);
2204 }
2205
2206 void os::numa_make_global(char *addr, size_t bytes) {
2207 }
2208
2209 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2210 }
2211
2212 bool os::numa_topology_changed() { return false; }
2213
2214 size_t os::numa_get_groups_num() {
2215 return 1;
2216 }
2217
2218 int os::numa_get_group_id() {
2219 return 0;
2220 }
2221
2222 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2223 if (size > 0) {
2224 ids[0] = 0;
2225 return 1;
2226 }
2227 return 0;
2228 }
2229
2230 bool os::get_page_info(char *start, page_info* info) {
2231 return false;
2232 }
2233
2234 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2235 return end;
2236 }
2237
2238
2239 bool os::pd_uncommit_memory(char* addr, size_t size) {
2240 #ifdef __OpenBSD__
2241 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2242 return ::mprotect(addr, size, PROT_NONE) == 0;
2243 #else
2244 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2245 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2246 return res != (uintptr_t) MAP_FAILED;
2247 #endif
2248 }
2249
2250 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2251 return os::commit_memory(addr, size, !ExecMem);
2252 }
2253
2254 // If this is a growable mapping, remove the guard pages entirely by
2255 // munmap()ping them. If not, just call uncommit_memory().
2256 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2257 return os::uncommit_memory(addr, size);
2258 }
2259
2260 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2261 // at 'requested_addr'. If there are existing memory mappings at the same
2262 // location, however, they will be overwritten. If 'fixed' is false,
2263 // 'requested_addr' is only treated as a hint, the return value may or
2264 // may not start from the requested address. Unlike Bsd mmap(), this
2265 // function returns NULL to indicate failure.
2266 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2267 char * addr;
2268 int flags;
2269
2270 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2271 if (fixed) {
2272 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2273 flags |= MAP_FIXED;
2274 }
2275
2276 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2277 // touch an uncommitted page. Otherwise, the read/write might
2278 // succeed if we have enough swap space to back the physical page.
2279 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2280 flags, -1, 0);
2281
2282 return addr == MAP_FAILED ? NULL : addr;
2283 }
2284
2285 static int anon_munmap(char * addr, size_t size) {
2286 return ::munmap(addr, size) == 0;
2287 }
2288
2289 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2290 size_t alignment_hint) {
2291 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2292 }
2293
2294 bool os::pd_release_memory(char* addr, size_t size) {
2295 return anon_munmap(addr, size);
2296 }
2297
2298 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2299 // Bsd wants the mprotect address argument to be page aligned.
2300 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2301
2302 // According to SUSv3, mprotect() should only be used with mappings
2303 // established by mmap(), and mmap() always maps whole pages. Unaligned
2304 // 'addr' likely indicates problem in the VM (e.g. trying to change
2305 // protection of malloc'ed or statically allocated memory). Check the
2306 // caller if you hit this assert.
2307 assert(addr == bottom, "sanity check");
2308
2309 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2310 return ::mprotect(bottom, size, prot) == 0;
2311 }
2312
2313 // Set protections specified
2314 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2315 bool is_committed) {
2316 unsigned int p = 0;
2317 switch (prot) {
2318 case MEM_PROT_NONE: p = PROT_NONE; break;
2319 case MEM_PROT_READ: p = PROT_READ; break;
2320 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2321 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2322 default:
2323 ShouldNotReachHere();
2324 }
2325 // is_committed is unused.
2326 return bsd_mprotect(addr, bytes, p);
2327 }
2328
2329 bool os::guard_memory(char* addr, size_t size) {
2330 return bsd_mprotect(addr, size, PROT_NONE);
2331 }
2332
2333 bool os::unguard_memory(char* addr, size_t size) {
2334 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2335 }
2336
2337 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2338 return false;
2339 }
2340
2341 // Large page support
2342
2343 static size_t _large_page_size = 0;
2344
2345 void os::large_page_init() {
2346 }
2347
2348
2349 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2350 fatal("This code is not used or maintained.");
2351
2352 // "exec" is passed in but not used. Creating the shared image for
2353 // the code cache doesn't have an SHM_X executable permission to check.
2354 assert(UseLargePages && UseSHM, "only for SHM large pages");
2355
2356 key_t key = IPC_PRIVATE;
2357 char *addr;
2358
2359 bool warn_on_failure = UseLargePages &&
2360 (!FLAG_IS_DEFAULT(UseLargePages) ||
2361 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2362
2363 // Create a large shared memory region to attach to based on size.
2364 // Currently, size is the total size of the heap
2365 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2366 if (shmid == -1) {
2367 // Possible reasons for shmget failure:
2368 // 1. shmmax is too small for Java heap.
2369 // > check shmmax value: cat /proc/sys/kernel/shmmax
2370 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2371 // 2. not enough large page memory.
2372 // > check available large pages: cat /proc/meminfo
2373 // > increase amount of large pages:
2374 // echo new_value > /proc/sys/vm/nr_hugepages
2375 // Note 1: different Bsd may use different name for this property,
2376 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2377 // Note 2: it's possible there's enough physical memory available but
2378 // they are so fragmented after a long run that they can't
2379 // coalesce into large pages. Try to reserve large pages when
2380 // the system is still "fresh".
2381 if (warn_on_failure) {
2382 warning("Failed to reserve shared memory (errno = %d).", errno);
2383 }
2384 return NULL;
2385 }
2386
2387 // attach to the region
2388 addr = (char*)shmat(shmid, req_addr, 0);
2389 int err = errno;
2390
2391 // Remove shmid. If shmat() is successful, the actual shared memory segment
2392 // will be deleted when it's detached by shmdt() or when the process
2393 // terminates. If shmat() is not successful this will remove the shared
2394 // segment immediately.
2395 shmctl(shmid, IPC_RMID, NULL);
2396
2397 if ((intptr_t)addr == -1) {
2398 if (warn_on_failure) {
2399 warning("Failed to attach shared memory (errno = %d).", err);
2400 }
2401 return NULL;
2402 }
2403
2404 // The memory is committed
2405 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2406
2407 return addr;
2408 }
2409
2410 bool os::release_memory_special(char* base, size_t bytes) {
2411 if (MemTracker::tracking_level() > NMT_minimal) {
2412 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2413 // detaching the SHM segment will also delete it, see reserve_memory_special()
2414 int rslt = shmdt(base);
2415 if (rslt == 0) {
2416 tkr.record((address)base, bytes);
2417 return true;
2418 } else {
2419 return false;
2420 }
2421 } else {
2422 return shmdt(base) == 0;
2423 }
2424 }
2425
2426 size_t os::large_page_size() {
2427 return _large_page_size;
2428 }
2429
2430 // HugeTLBFS allows application to commit large page memory on demand;
2431 // with SysV SHM the entire memory region must be allocated as shared
2432 // memory.
2433 bool os::can_commit_large_page_memory() {
2434 return UseHugeTLBFS;
2435 }
2436
2437 bool os::can_execute_large_page_memory() {
2438 return UseHugeTLBFS;
2439 }
2440
2441 // Reserve memory at an arbitrary address, only if that area is
2442 // available (and not reserved for something else).
2443
2444 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2445 const int max_tries = 10;
2446 char* base[max_tries];
2447 size_t size[max_tries];
2448 const size_t gap = 0x000000;
2449
2450 // Assert only that the size is a multiple of the page size, since
2451 // that's all that mmap requires, and since that's all we really know
2452 // about at this low abstraction level. If we need higher alignment,
2453 // we can either pass an alignment to this method or verify alignment
2454 // in one of the methods further up the call chain. See bug 5044738.
2455 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2456
2457 // Repeatedly allocate blocks until the block is allocated at the
2458 // right spot.
2459
2460 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2461 // if kernel honors the hint then we can return immediately.
2462 char * addr = anon_mmap(requested_addr, bytes, false);
2463 if (addr == requested_addr) {
2464 return requested_addr;
2465 }
2466
2467 if (addr != NULL) {
2468 // mmap() is successful but it fails to reserve at the requested address
2469 anon_munmap(addr, bytes);
2470 }
2471
2472 int i;
2473 for (i = 0; i < max_tries; ++i) {
2474 base[i] = reserve_memory(bytes);
2475
2476 if (base[i] != NULL) {
2477 // Is this the block we wanted?
2478 if (base[i] == requested_addr) {
2479 size[i] = bytes;
2480 break;
2481 }
2482
2483 // Does this overlap the block we wanted? Give back the overlapped
2484 // parts and try again.
2485
2486 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2487 if (top_overlap >= 0 && top_overlap < bytes) {
2488 unmap_memory(base[i], top_overlap);
2489 base[i] += top_overlap;
2490 size[i] = bytes - top_overlap;
2491 } else {
2492 size_t bottom_overlap = base[i] + bytes - requested_addr;
2493 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2494 unmap_memory(requested_addr, bottom_overlap);
2495 size[i] = bytes - bottom_overlap;
2496 } else {
2497 size[i] = bytes;
2498 }
2499 }
2500 }
2501 }
2502
2503 // Give back the unused reserved pieces.
2504
2505 for (int j = 0; j < i; ++j) {
2506 if (base[j] != NULL) {
2507 unmap_memory(base[j], size[j]);
2508 }
2509 }
2510
2511 if (i < max_tries) {
2512 return requested_addr;
2513 } else {
2514 return NULL;
2515 }
2516 }
2517
2518 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2519 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2520 }
2521
2522 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2523 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2524 }
2525
2526 void os::naked_short_sleep(jlong ms) {
2527 struct timespec req;
2528
2529 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2530 req.tv_sec = 0;
2531 if (ms > 0) {
2532 req.tv_nsec = (ms % 1000) * 1000000;
2533 } else {
2534 req.tv_nsec = 1;
2535 }
2536
2537 nanosleep(&req, NULL);
2538
2539 return;
2540 }
2541
2542 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2543 void os::infinite_sleep() {
2544 while (true) { // sleep forever ...
2545 ::sleep(100); // ... 100 seconds at a time
2546 }
2547 }
2548
2549 // Used to convert frequent JVM_Yield() to nops
2550 bool os::dont_yield() {
2551 return DontYieldALot;
2552 }
2553
2554 void os::naked_yield() {
2555 sched_yield();
2556 }
2557
2558 ////////////////////////////////////////////////////////////////////////////////
2559 // thread priority support
2560
2561 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2562 // only supports dynamic priority, static priority must be zero. For real-time
2563 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2564 // However, for large multi-threaded applications, SCHED_RR is not only slower
2565 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2566 // of 5 runs - Sep 2005).
2567 //
2568 // The following code actually changes the niceness of kernel-thread/LWP. It
2569 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2570 // not the entire user process, and user level threads are 1:1 mapped to kernel
2571 // threads. It has always been the case, but could change in the future. For
2572 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2573 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2574
2575 #if !defined(__APPLE__)
2576 int os::java_to_os_priority[CriticalPriority + 1] = {
2577 19, // 0 Entry should never be used
2578
2579 0, // 1 MinPriority
2580 3, // 2
2581 6, // 3
2582
2583 10, // 4
2584 15, // 5 NormPriority
2585 18, // 6
2586
2587 21, // 7
2588 25, // 8
2589 28, // 9 NearMaxPriority
2590
2591 31, // 10 MaxPriority
2592
2593 31 // 11 CriticalPriority
2594 };
2595 #else
2596 // Using Mach high-level priority assignments
2597 int os::java_to_os_priority[CriticalPriority + 1] = {
2598 0, // 0 Entry should never be used (MINPRI_USER)
2599
2600 27, // 1 MinPriority
2601 28, // 2
2602 29, // 3
2603
2604 30, // 4
2605 31, // 5 NormPriority (BASEPRI_DEFAULT)
2606 32, // 6
2607
2608 33, // 7
2609 34, // 8
2610 35, // 9 NearMaxPriority
2611
2612 36, // 10 MaxPriority
2613
2614 36 // 11 CriticalPriority
2615 };
2616 #endif
2617
2618 static int prio_init() {
2619 if (ThreadPriorityPolicy == 1) {
2620 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2621 // if effective uid is not root. Perhaps, a more elegant way of doing
2622 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2623 if (geteuid() != 0) {
2624 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2625 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2626 }
2627 ThreadPriorityPolicy = 0;
2628 }
2629 }
2630 if (UseCriticalJavaThreadPriority) {
2631 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2632 }
2633 return 0;
2634 }
2635
2636 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2637 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2638
2639 #ifdef __OpenBSD__
2640 // OpenBSD pthread_setprio starves low priority threads
2641 return OS_OK;
2642 #elif defined(__FreeBSD__)
2643 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2644 #elif defined(__APPLE__) || defined(__NetBSD__)
2645 struct sched_param sp;
2646 int policy;
2647 pthread_t self = pthread_self();
2648
2649 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2650 return OS_ERR;
2651 }
2652
2653 sp.sched_priority = newpri;
2654 if (pthread_setschedparam(self, policy, &sp) != 0) {
2655 return OS_ERR;
2656 }
2657
2658 return OS_OK;
2659 #else
2660 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2661 return (ret == 0) ? OS_OK : OS_ERR;
2662 #endif
2663 }
2664
2665 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2666 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2667 *priority_ptr = java_to_os_priority[NormPriority];
2668 return OS_OK;
2669 }
2670
2671 errno = 0;
2672 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2673 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2674 #elif defined(__APPLE__) || defined(__NetBSD__)
2675 int policy;
2676 struct sched_param sp;
2677
2678 pthread_getschedparam(pthread_self(), &policy, &sp);
2679 *priority_ptr = sp.sched_priority;
2680 #else
2681 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2682 #endif
2683 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2684 }
2685
2686 // Hint to the underlying OS that a task switch would not be good.
2687 // Void return because it's a hint and can fail.
2688 void os::hint_no_preempt() {}
2689
2690 ////////////////////////////////////////////////////////////////////////////////
2691 // suspend/resume support
2692
2693 // the low-level signal-based suspend/resume support is a remnant from the
2694 // old VM-suspension that used to be for java-suspension, safepoints etc,
2695 // within hotspot. Now there is a single use-case for this:
2696 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2697 // that runs in the watcher thread.
2698 // The remaining code is greatly simplified from the more general suspension
2699 // code that used to be used.
2700 //
2701 // The protocol is quite simple:
2702 // - suspend:
2703 // - sends a signal to the target thread
2704 // - polls the suspend state of the osthread using a yield loop
2705 // - target thread signal handler (SR_handler) sets suspend state
2706 // and blocks in sigsuspend until continued
2707 // - resume:
2708 // - sets target osthread state to continue
2709 // - sends signal to end the sigsuspend loop in the SR_handler
2710 //
2711 // Note that the SR_lock plays no role in this suspend/resume protocol.
2712
2713 static void resume_clear_context(OSThread *osthread) {
2714 osthread->set_ucontext(NULL);
2715 osthread->set_siginfo(NULL);
2716 }
2717
2718 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2719 osthread->set_ucontext(context);
2720 osthread->set_siginfo(siginfo);
2721 }
2722
2723 // Handler function invoked when a thread's execution is suspended or
2724 // resumed. We have to be careful that only async-safe functions are
2725 // called here (Note: most pthread functions are not async safe and
2726 // should be avoided.)
2727 //
2728 // Note: sigwait() is a more natural fit than sigsuspend() from an
2729 // interface point of view, but sigwait() prevents the signal hander
2730 // from being run. libpthread would get very confused by not having
2731 // its signal handlers run and prevents sigwait()'s use with the
2732 // mutex granting granting signal.
2733 //
2734 // Currently only ever called on the VMThread or JavaThread
2735 //
2736 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2737 // Save and restore errno to avoid confusing native code with EINTR
2738 // after sigsuspend.
2739 int old_errno = errno;
2740
2741 Thread* thread = Thread::current();
2742 OSThread* osthread = thread->osthread();
2743 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2744
2745 os::SuspendResume::State current = osthread->sr.state();
2746 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2747 suspend_save_context(osthread, siginfo, context);
2748
2749 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2750 os::SuspendResume::State state = osthread->sr.suspended();
2751 if (state == os::SuspendResume::SR_SUSPENDED) {
2752 sigset_t suspend_set; // signals for sigsuspend()
2753
2754 // get current set of blocked signals and unblock resume signal
2755 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2756 sigdelset(&suspend_set, SR_signum);
2757
2758 sr_semaphore.signal();
2759 // wait here until we are resumed
2760 while (1) {
2761 sigsuspend(&suspend_set);
2762
2763 os::SuspendResume::State result = osthread->sr.running();
2764 if (result == os::SuspendResume::SR_RUNNING) {
2765 sr_semaphore.signal();
2766 break;
2767 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2768 ShouldNotReachHere();
2769 }
2770 }
2771
2772 } else if (state == os::SuspendResume::SR_RUNNING) {
2773 // request was cancelled, continue
2774 } else {
2775 ShouldNotReachHere();
2776 }
2777
2778 resume_clear_context(osthread);
2779 } else if (current == os::SuspendResume::SR_RUNNING) {
2780 // request was cancelled, continue
2781 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2782 // ignore
2783 } else {
2784 // ignore
2785 }
2786
2787 errno = old_errno;
2788 }
2789
2790
2791 static int SR_initialize() {
2792 struct sigaction act;
2793 char *s;
2794 // Get signal number to use for suspend/resume
2795 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2796 int sig = ::strtol(s, 0, 10);
2797 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2798 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2799 SR_signum = sig;
2800 } else {
2801 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2802 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2803 }
2804 }
2805
2806 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2807 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2808
2809 sigemptyset(&SR_sigset);
2810 sigaddset(&SR_sigset, SR_signum);
2811
2812 // Set up signal handler for suspend/resume
2813 act.sa_flags = SA_RESTART|SA_SIGINFO;
2814 act.sa_handler = (void (*)(int)) SR_handler;
2815
2816 // SR_signum is blocked by default.
2817 // 4528190 - We also need to block pthread restart signal (32 on all
2818 // supported Bsd platforms). Note that BsdThreads need to block
2819 // this signal for all threads to work properly. So we don't have
2820 // to use hard-coded signal number when setting up the mask.
2821 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2822
2823 if (sigaction(SR_signum, &act, 0) == -1) {
2824 return -1;
2825 }
2826
2827 // Save signal flag
2828 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2829 return 0;
2830 }
2831
2832 static int sr_notify(OSThread* osthread) {
2833 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2834 assert_status(status == 0, status, "pthread_kill");
2835 return status;
2836 }
2837
2838 // "Randomly" selected value for how long we want to spin
2839 // before bailing out on suspending a thread, also how often
2840 // we send a signal to a thread we want to resume
2841 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2842 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2843
2844 // returns true on success and false on error - really an error is fatal
2845 // but this seems the normal response to library errors
2846 static bool do_suspend(OSThread* osthread) {
2847 assert(osthread->sr.is_running(), "thread should be running");
2848 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2849
2850 // mark as suspended and send signal
2851 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2852 // failed to switch, state wasn't running?
2853 ShouldNotReachHere();
2854 return false;
2855 }
2856
2857 if (sr_notify(osthread) != 0) {
2858 ShouldNotReachHere();
2859 }
2860
2861 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2862 while (true) {
2863 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2864 break;
2865 } else {
2866 // timeout
2867 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2868 if (cancelled == os::SuspendResume::SR_RUNNING) {
2869 return false;
2870 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2871 // make sure that we consume the signal on the semaphore as well
2872 sr_semaphore.wait();
2873 break;
2874 } else {
2875 ShouldNotReachHere();
2876 return false;
2877 }
2878 }
2879 }
2880
2881 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2882 return true;
2883 }
2884
2885 static void do_resume(OSThread* osthread) {
2886 assert(osthread->sr.is_suspended(), "thread should be suspended");
2887 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2888
2889 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2890 // failed to switch to WAKEUP_REQUEST
2891 ShouldNotReachHere();
2892 return;
2893 }
2894
2895 while (true) {
2896 if (sr_notify(osthread) == 0) {
2897 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2898 if (osthread->sr.is_running()) {
2899 return;
2900 }
2901 }
2902 } else {
2903 ShouldNotReachHere();
2904 }
2905 }
2906
2907 guarantee(osthread->sr.is_running(), "Must be running!");
2908 }
2909
2910 ///////////////////////////////////////////////////////////////////////////////////
2911 // signal handling (except suspend/resume)
2912
2913 // This routine may be used by user applications as a "hook" to catch signals.
2914 // The user-defined signal handler must pass unrecognized signals to this
2915 // routine, and if it returns true (non-zero), then the signal handler must
2916 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2917 // routine will never retun false (zero), but instead will execute a VM panic
2918 // routine kill the process.
2919 //
2920 // If this routine returns false, it is OK to call it again. This allows
2921 // the user-defined signal handler to perform checks either before or after
2922 // the VM performs its own checks. Naturally, the user code would be making
2923 // a serious error if it tried to handle an exception (such as a null check
2924 // or breakpoint) that the VM was generating for its own correct operation.
2925 //
2926 // This routine may recognize any of the following kinds of signals:
2927 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2928 // It should be consulted by handlers for any of those signals.
2929 //
2930 // The caller of this routine must pass in the three arguments supplied
2931 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2932 // field of the structure passed to sigaction(). This routine assumes that
2933 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2934 //
2935 // Note that the VM will print warnings if it detects conflicting signal
2936 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2937 //
2938 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2939 void* ucontext,
2940 int abort_if_unrecognized);
2941
2942 void signalHandler(int sig, siginfo_t* info, void* uc) {
2943 assert(info != NULL && uc != NULL, "it must be old kernel");
2944 int orig_errno = errno; // Preserve errno value over signal handler.
2945 JVM_handle_bsd_signal(sig, info, uc, true);
2946 errno = orig_errno;
2947 }
2948
2949
2950 // This boolean allows users to forward their own non-matching signals
2951 // to JVM_handle_bsd_signal, harmlessly.
2952 bool os::Bsd::signal_handlers_are_installed = false;
2953
2954 // For signal-chaining
2955 struct sigaction sigact[NSIG];
2956 uint32_t sigs = 0;
2957 #if (32 < NSIG-1)
2958 #error "Not all signals can be encoded in sigs. Adapt its type!"
2959 #endif
2960 bool os::Bsd::libjsig_is_loaded = false;
2961 typedef struct sigaction *(*get_signal_t)(int);
2962 get_signal_t os::Bsd::get_signal_action = NULL;
2963
2964 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2965 struct sigaction *actp = NULL;
2966
2967 if (libjsig_is_loaded) {
2968 // Retrieve the old signal handler from libjsig
2969 actp = (*get_signal_action)(sig);
2970 }
2971 if (actp == NULL) {
2972 // Retrieve the preinstalled signal handler from jvm
2973 actp = get_preinstalled_handler(sig);
2974 }
2975
2976 return actp;
2977 }
2978
2979 static bool call_chained_handler(struct sigaction *actp, int sig,
2980 siginfo_t *siginfo, void *context) {
2981 // Call the old signal handler
2982 if (actp->sa_handler == SIG_DFL) {
2983 // It's more reasonable to let jvm treat it as an unexpected exception
2984 // instead of taking the default action.
2985 return false;
2986 } else if (actp->sa_handler != SIG_IGN) {
2987 if ((actp->sa_flags & SA_NODEFER) == 0) {
2988 // automaticlly block the signal
2989 sigaddset(&(actp->sa_mask), sig);
2990 }
2991
2992 sa_handler_t hand;
2993 sa_sigaction_t sa;
2994 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2995 // retrieve the chained handler
2996 if (siginfo_flag_set) {
2997 sa = actp->sa_sigaction;
2998 } else {
2999 hand = actp->sa_handler;
3000 }
3001
3002 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3003 actp->sa_handler = SIG_DFL;
3004 }
3005
3006 // try to honor the signal mask
3007 sigset_t oset;
3008 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3009
3010 // call into the chained handler
3011 if (siginfo_flag_set) {
3012 (*sa)(sig, siginfo, context);
3013 } else {
3014 (*hand)(sig);
3015 }
3016
3017 // restore the signal mask
3018 pthread_sigmask(SIG_SETMASK, &oset, 0);
3019 }
3020 // Tell jvm's signal handler the signal is taken care of.
3021 return true;
3022 }
3023
3024 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3025 bool chained = false;
3026 // signal-chaining
3027 if (UseSignalChaining) {
3028 struct sigaction *actp = get_chained_signal_action(sig);
3029 if (actp != NULL) {
3030 chained = call_chained_handler(actp, sig, siginfo, context);
3031 }
3032 }
3033 return chained;
3034 }
3035
3036 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3037 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
3038 return &sigact[sig];
3039 }
3040 return NULL;
3041 }
3042
3043 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3044 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3045 sigact[sig] = oldAct;
3046 sigs |= (uint32_t)1 << (sig-1);
3047 }
3048
3049 // for diagnostic
3050 int sigflags[NSIG];
3051
3052 int os::Bsd::get_our_sigflags(int sig) {
3053 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3054 return sigflags[sig];
3055 }
3056
3057 void os::Bsd::set_our_sigflags(int sig, int flags) {
3058 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3059 if (sig > 0 && sig < NSIG) {
3060 sigflags[sig] = flags;
3061 }
3062 }
3063
3064 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3065 // Check for overwrite.
3066 struct sigaction oldAct;
3067 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3068
3069 void* oldhand = oldAct.sa_sigaction
3070 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3071 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3072 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3073 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3074 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3075 if (AllowUserSignalHandlers || !set_installed) {
3076 // Do not overwrite; user takes responsibility to forward to us.
3077 return;
3078 } else if (UseSignalChaining) {
3079 // save the old handler in jvm
3080 save_preinstalled_handler(sig, oldAct);
3081 // libjsig also interposes the sigaction() call below and saves the
3082 // old sigaction on it own.
3083 } else {
3084 fatal("Encountered unexpected pre-existing sigaction handler "
3085 "%#lx for signal %d.", (long)oldhand, sig);
3086 }
3087 }
3088
3089 struct sigaction sigAct;
3090 sigfillset(&(sigAct.sa_mask));
3091 sigAct.sa_handler = SIG_DFL;
3092 if (!set_installed) {
3093 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3094 } else {
3095 sigAct.sa_sigaction = signalHandler;
3096 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3097 }
3098 #ifdef __APPLE__
3099 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3100 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3101 // if the signal handler declares it will handle it on alternate stack.
3102 // Notice we only declare we will handle it on alt stack, but we are not
3103 // actually going to use real alt stack - this is just a workaround.
3104 // Please see ux_exception.c, method catch_mach_exception_raise for details
3105 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3106 if (sig == SIGSEGV) {
3107 sigAct.sa_flags |= SA_ONSTACK;
3108 }
3109 #endif
3110
3111 // Save flags, which are set by ours
3112 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3113 sigflags[sig] = sigAct.sa_flags;
3114
3115 int ret = sigaction(sig, &sigAct, &oldAct);
3116 assert(ret == 0, "check");
3117
3118 void* oldhand2 = oldAct.sa_sigaction
3119 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3120 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3121 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3122 }
3123
3124 // install signal handlers for signals that HotSpot needs to
3125 // handle in order to support Java-level exception handling.
3126
3127 void os::Bsd::install_signal_handlers() {
3128 if (!signal_handlers_are_installed) {
3129 signal_handlers_are_installed = true;
3130
3131 // signal-chaining
3132 typedef void (*signal_setting_t)();
3133 signal_setting_t begin_signal_setting = NULL;
3134 signal_setting_t end_signal_setting = NULL;
3135 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3136 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3137 if (begin_signal_setting != NULL) {
3138 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3139 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3140 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3141 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3142 libjsig_is_loaded = true;
3143 assert(UseSignalChaining, "should enable signal-chaining");
3144 }
3145 if (libjsig_is_loaded) {
3146 // Tell libjsig jvm is setting signal handlers
3147 (*begin_signal_setting)();
3148 }
3149
3150 set_signal_handler(SIGSEGV, true);
3151 set_signal_handler(SIGPIPE, true);
3152 set_signal_handler(SIGBUS, true);
3153 set_signal_handler(SIGILL, true);
3154 set_signal_handler(SIGFPE, true);
3155 set_signal_handler(SIGXFSZ, true);
3156
3157 #if defined(__APPLE__)
3158 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3159 // signals caught and handled by the JVM. To work around this, we reset the mach task
3160 // signal handler that's placed on our process by CrashReporter. This disables
3161 // CrashReporter-based reporting.
3162 //
3163 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3164 // on caught fatal signals.
3165 //
3166 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3167 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3168 // exception handling, while leaving the standard BSD signal handlers functional.
3169 kern_return_t kr;
3170 kr = task_set_exception_ports(mach_task_self(),
3171 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3172 MACH_PORT_NULL,
3173 EXCEPTION_STATE_IDENTITY,
3174 MACHINE_THREAD_STATE);
3175
3176 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3177 #endif
3178
3179 if (libjsig_is_loaded) {
3180 // Tell libjsig jvm finishes setting signal handlers
3181 (*end_signal_setting)();
3182 }
3183
3184 // We don't activate signal checker if libjsig is in place, we trust ourselves
3185 // and if UserSignalHandler is installed all bets are off
3186 if (CheckJNICalls) {
3187 if (libjsig_is_loaded) {
3188 if (PrintJNIResolving) {
3189 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3190 }
3191 check_signals = false;
3192 }
3193 if (AllowUserSignalHandlers) {
3194 if (PrintJNIResolving) {
3195 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3196 }
3197 check_signals = false;
3198 }
3199 }
3200 }
3201 }
3202
3203
3204 /////
3205 // glibc on Bsd platform uses non-documented flag
3206 // to indicate, that some special sort of signal
3207 // trampoline is used.
3208 // We will never set this flag, and we should
3209 // ignore this flag in our diagnostic
3210 #ifdef SIGNIFICANT_SIGNAL_MASK
3211 #undef SIGNIFICANT_SIGNAL_MASK
3212 #endif
3213 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3214
3215 static const char* get_signal_handler_name(address handler,
3216 char* buf, int buflen) {
3217 int offset;
3218 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3219 if (found) {
3220 // skip directory names
3221 const char *p1, *p2;
3222 p1 = buf;
3223 size_t len = strlen(os::file_separator());
3224 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3225 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3226 } else {
3227 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3228 }
3229 return buf;
3230 }
3231
3232 static void print_signal_handler(outputStream* st, int sig,
3233 char* buf, size_t buflen) {
3234 struct sigaction sa;
3235
3236 sigaction(sig, NULL, &sa);
3237
3238 // See comment for SIGNIFICANT_SIGNAL_MASK define
3239 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3240
3241 st->print("%s: ", os::exception_name(sig, buf, buflen));
3242
3243 address handler = (sa.sa_flags & SA_SIGINFO)
3244 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3245 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3246
3247 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3248 st->print("SIG_DFL");
3249 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3250 st->print("SIG_IGN");
3251 } else {
3252 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3253 }
3254
3255 st->print(", sa_mask[0]=");
3256 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3257
3258 address rh = VMError::get_resetted_sighandler(sig);
3259 // May be, handler was resetted by VMError?
3260 if (rh != NULL) {
3261 handler = rh;
3262 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3263 }
3264
3265 st->print(", sa_flags=");
3266 os::Posix::print_sa_flags(st, sa.sa_flags);
3267
3268 // Check: is it our handler?
3269 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3270 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3271 // It is our signal handler
3272 // check for flags, reset system-used one!
3273 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3274 st->print(
3275 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3276 os::Bsd::get_our_sigflags(sig));
3277 }
3278 }
3279 st->cr();
3280 }
3281
3282
3283 #define DO_SIGNAL_CHECK(sig) \
3284 do { \
3285 if (!sigismember(&check_signal_done, sig)) { \
3286 os::Bsd::check_signal_handler(sig); \
3287 } \
3288 } while (0)
3289
3290 // This method is a periodic task to check for misbehaving JNI applications
3291 // under CheckJNI, we can add any periodic checks here
3292
3293 void os::run_periodic_checks() {
3294
3295 if (check_signals == false) return;
3296
3297 // SEGV and BUS if overridden could potentially prevent
3298 // generation of hs*.log in the event of a crash, debugging
3299 // such a case can be very challenging, so we absolutely
3300 // check the following for a good measure:
3301 DO_SIGNAL_CHECK(SIGSEGV);
3302 DO_SIGNAL_CHECK(SIGILL);
3303 DO_SIGNAL_CHECK(SIGFPE);
3304 DO_SIGNAL_CHECK(SIGBUS);
3305 DO_SIGNAL_CHECK(SIGPIPE);
3306 DO_SIGNAL_CHECK(SIGXFSZ);
3307
3308
3309 // ReduceSignalUsage allows the user to override these handlers
3310 // see comments at the very top and jvm_solaris.h
3311 if (!ReduceSignalUsage) {
3312 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3313 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3314 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3315 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3316 }
3317
3318 DO_SIGNAL_CHECK(SR_signum);
3319 }
3320
3321 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3322
3323 static os_sigaction_t os_sigaction = NULL;
3324
3325 void os::Bsd::check_signal_handler(int sig) {
3326 char buf[O_BUFLEN];
3327 address jvmHandler = NULL;
3328
3329
3330 struct sigaction act;
3331 if (os_sigaction == NULL) {
3332 // only trust the default sigaction, in case it has been interposed
3333 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3334 if (os_sigaction == NULL) return;
3335 }
3336
3337 os_sigaction(sig, (struct sigaction*)NULL, &act);
3338
3339
3340 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3341
3342 address thisHandler = (act.sa_flags & SA_SIGINFO)
3343 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3344 : CAST_FROM_FN_PTR(address, act.sa_handler);
3345
3346
3347 switch (sig) {
3348 case SIGSEGV:
3349 case SIGBUS:
3350 case SIGFPE:
3351 case SIGPIPE:
3352 case SIGILL:
3353 case SIGXFSZ:
3354 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3355 break;
3356
3357 case SHUTDOWN1_SIGNAL:
3358 case SHUTDOWN2_SIGNAL:
3359 case SHUTDOWN3_SIGNAL:
3360 case BREAK_SIGNAL:
3361 jvmHandler = (address)user_handler();
3362 break;
3363
3364 default:
3365 if (sig == SR_signum) {
3366 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3367 } else {
3368 return;
3369 }
3370 break;
3371 }
3372
3373 if (thisHandler != jvmHandler) {
3374 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3375 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3376 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3377 // No need to check this sig any longer
3378 sigaddset(&check_signal_done, sig);
3379 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3380 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3381 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3382 exception_name(sig, buf, O_BUFLEN));
3383 }
3384 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3385 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3386 tty->print("expected:");
3387 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3388 tty->cr();
3389 tty->print(" found:");
3390 os::Posix::print_sa_flags(tty, act.sa_flags);
3391 tty->cr();
3392 // No need to check this sig any longer
3393 sigaddset(&check_signal_done, sig);
3394 }
3395
3396 // Dump all the signal
3397 if (sigismember(&check_signal_done, sig)) {
3398 print_signal_handlers(tty, buf, O_BUFLEN);
3399 }
3400 }
3401
3402 extern void report_error(char* file_name, int line_no, char* title,
3403 char* format, ...);
3404
3405 // this is called _before_ the most of global arguments have been parsed
3406 void os::init(void) {
3407 char dummy; // used to get a guess on initial stack address
3408 // first_hrtime = gethrtime();
3409
3410 // With BsdThreads the JavaMain thread pid (primordial thread)
3411 // is different than the pid of the java launcher thread.
3412 // So, on Bsd, the launcher thread pid is passed to the VM
3413 // via the sun.java.launcher.pid property.
3414 // Use this property instead of getpid() if it was correctly passed.
3415 // See bug 6351349.
3416 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3417
3418 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3419
3420 clock_tics_per_sec = CLK_TCK;
3421
3422 init_random(1234567);
3423
3424 ThreadCritical::initialize();
3425
3426 Bsd::set_page_size(getpagesize());
3427 if (Bsd::page_size() == -1) {
3428 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno));
3429 }
3430 init_page_sizes((size_t) Bsd::page_size());
3431
3432 Bsd::initialize_system_info();
3433
3434 // main_thread points to the aboriginal thread
3435 Bsd::_main_thread = pthread_self();
3436
3437 Bsd::clock_init();
3438 initial_time_count = javaTimeNanos();
3439
3440 #ifdef __APPLE__
3441 // XXXDARWIN
3442 // Work around the unaligned VM callbacks in hotspot's
3443 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3444 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3445 // alignment when doing symbol lookup. To work around this, we force early
3446 // binding of all symbols now, thus binding when alignment is known-good.
3447 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3448 #endif
3449 }
3450
3451 // To install functions for atexit system call
3452 extern "C" {
3453 static void perfMemory_exit_helper() {
3454 perfMemory_exit();
3455 }
3456 }
3457
3458 // this is called _after_ the global arguments have been parsed
3459 jint os::init_2(void) {
3460 // Allocate a single page and mark it as readable for safepoint polling
3461 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3462 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3463
3464 os::set_polling_page(polling_page);
3465
3466 #ifndef PRODUCT
3467 if (Verbose && PrintMiscellaneous) {
3468 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n",
3469 (intptr_t)polling_page);
3470 }
3471 #endif
3472
3473 if (!UseMembar) {
3474 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3475 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3476 os::set_memory_serialize_page(mem_serialize_page);
3477
3478 #ifndef PRODUCT
3479 if (Verbose && PrintMiscellaneous) {
3480 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n",
3481 (intptr_t)mem_serialize_page);
3482 }
3483 #endif
3484 }
3485
3486 // initialize suspend/resume support - must do this before signal_sets_init()
3487 if (SR_initialize() != 0) {
3488 perror("SR_initialize failed");
3489 return JNI_ERR;
3490 }
3491
3492 Bsd::signal_sets_init();
3493 Bsd::install_signal_handlers();
3494
3495 // Check minimum allowable stack size for thread creation and to initialize
3496 // the java system classes, including StackOverflowError - depends on page
3497 // size. Add a page for compiler2 recursion in main thread.
3498 // Add in 2*BytesPerWord times page size to account for VM stack during
3499 // class initialization depending on 32 or 64 bit VM.
3500 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3501 JavaThread::stack_guard_zone_size() +
3502 JavaThread::stack_shadow_zone_size() +
3503 (2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3504
3505 size_t threadStackSizeInBytes = ThreadStackSize * K;
3506 if (threadStackSizeInBytes != 0 &&
3507 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3508 tty->print_cr("\nThe stack size specified is too small, "
3509 "Specify at least %dk",
3510 os::Bsd::min_stack_allowed/ K);
3511 return JNI_ERR;
3512 }
3513
3514 // Make the stack size a multiple of the page size so that
3515 // the yellow/red zones can be guarded.
3516 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3517 vm_page_size()));
3518
3519 if (MaxFDLimit) {
3520 // set the number of file descriptors to max. print out error
3521 // if getrlimit/setrlimit fails but continue regardless.
3522 struct rlimit nbr_files;
3523 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3524 if (status != 0) {
3525 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3526 perror("os::init_2 getrlimit failed");
3527 }
3528 } else {
3529 nbr_files.rlim_cur = nbr_files.rlim_max;
3530
3531 #ifdef __APPLE__
3532 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3533 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3534 // be used instead
3535 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3536 #endif
3537
3538 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3539 if (status != 0) {
3540 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3541 perror("os::init_2 setrlimit failed");
3542 }
3543 }
3544 }
3545 }
3546
3547 // at-exit methods are called in the reverse order of their registration.
3548 // atexit functions are called on return from main or as a result of a
3549 // call to exit(3C). There can be only 32 of these functions registered
3550 // and atexit() does not set errno.
3551
3552 if (PerfAllowAtExitRegistration) {
3553 // only register atexit functions if PerfAllowAtExitRegistration is set.
3554 // atexit functions can be delayed until process exit time, which
3555 // can be problematic for embedded VM situations. Embedded VMs should
3556 // call DestroyJavaVM() to assure that VM resources are released.
3557
3558 // note: perfMemory_exit_helper atexit function may be removed in
3559 // the future if the appropriate cleanup code can be added to the
3560 // VM_Exit VMOperation's doit method.
3561 if (atexit(perfMemory_exit_helper) != 0) {
3562 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3563 }
3564 }
3565
3566 // initialize thread priority policy
3567 prio_init();
3568
3569 #ifdef __APPLE__
3570 // dynamically link to objective c gc registration
3571 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3572 if (handleLibObjc != NULL) {
3573 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3574 }
3575 #endif
3576
3577 return JNI_OK;
3578 }
3579
3580 // Mark the polling page as unreadable
3581 void os::make_polling_page_unreadable(void) {
3582 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3583 fatal("Could not disable polling page");
3584 }
3585 }
3586
3587 // Mark the polling page as readable
3588 void os::make_polling_page_readable(void) {
3589 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3590 fatal("Could not enable polling page");
3591 }
3592 }
3593
3594 int os::active_processor_count() {
3595 return _processor_count;
3596 }
3597
3598 void os::set_native_thread_name(const char *name) {
3599 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3600 // This is only supported in Snow Leopard and beyond
3601 if (name != NULL) {
3602 // Add a "Java: " prefix to the name
3603 char buf[MAXTHREADNAMESIZE];
3604 snprintf(buf, sizeof(buf), "Java: %s", name);
3605 pthread_setname_np(buf);
3606 }
3607 #endif
3608 }
3609
3610 bool os::distribute_processes(uint length, uint* distribution) {
3611 // Not yet implemented.
3612 return false;
3613 }
3614
3615 bool os::bind_to_processor(uint processor_id) {
3616 // Not yet implemented.
3617 return false;
3618 }
3619
3620 void os::SuspendedThreadTask::internal_do_task() {
3621 if (do_suspend(_thread->osthread())) {
3622 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3623 do_task(context);
3624 do_resume(_thread->osthread());
3625 }
3626 }
3627
3628 ///
3629 class PcFetcher : public os::SuspendedThreadTask {
3630 public:
3631 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3632 ExtendedPC result();
3633 protected:
3634 void do_task(const os::SuspendedThreadTaskContext& context);
3635 private:
3636 ExtendedPC _epc;
3637 };
3638
3639 ExtendedPC PcFetcher::result() {
3640 guarantee(is_done(), "task is not done yet.");
3641 return _epc;
3642 }
3643
3644 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3645 Thread* thread = context.thread();
3646 OSThread* osthread = thread->osthread();
3647 if (osthread->ucontext() != NULL) {
3648 _epc = os::Bsd::ucontext_get_pc((const ucontext_t *) context.ucontext());
3649 } else {
3650 // NULL context is unexpected, double-check this is the VMThread
3651 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3652 }
3653 }
3654
3655 // Suspends the target using the signal mechanism and then grabs the PC before
3656 // resuming the target. Used by the flat-profiler only
3657 ExtendedPC os::get_thread_pc(Thread* thread) {
3658 // Make sure that it is called by the watcher for the VMThread
3659 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3660 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3661
3662 PcFetcher fetcher(thread);
3663 fetcher.run();
3664 return fetcher.result();
3665 }
3666
3667 ////////////////////////////////////////////////////////////////////////////////
3668 // debug support
3669
3670 bool os::find(address addr, outputStream* st) {
3671 Dl_info dlinfo;
3672 memset(&dlinfo, 0, sizeof(dlinfo));
3673 if (dladdr(addr, &dlinfo) != 0) {
3674 st->print(PTR_FORMAT ": ", addr);
3675 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3676 st->print("%s+%#x", dlinfo.dli_sname,
3677 addr - (intptr_t)dlinfo.dli_saddr);
3678 } else if (dlinfo.dli_fbase != NULL) {
3679 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3680 } else {
3681 st->print("<absolute address>");
3682 }
3683 if (dlinfo.dli_fname != NULL) {
3684 st->print(" in %s", dlinfo.dli_fname);
3685 }
3686 if (dlinfo.dli_fbase != NULL) {
3687 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3688 }
3689 st->cr();
3690
3691 if (Verbose) {
3692 // decode some bytes around the PC
3693 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3694 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3695 address lowest = (address) dlinfo.dli_sname;
3696 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3697 if (begin < lowest) begin = lowest;
3698 Dl_info dlinfo2;
3699 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3700 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3701 end = (address) dlinfo2.dli_saddr;
3702 }
3703 Disassembler::decode(begin, end, st);
3704 }
3705 return true;
3706 }
3707 return false;
3708 }
3709
3710 ////////////////////////////////////////////////////////////////////////////////
3711 // misc
3712
3713 // This does not do anything on Bsd. This is basically a hook for being
3714 // able to use structured exception handling (thread-local exception filters)
3715 // on, e.g., Win32.
3716 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3717 const methodHandle& method, JavaCallArguments* args,
3718 Thread* thread) {
3719 f(value, method, args, thread);
3720 }
3721
3722 void os::print_statistics() {
3723 }
3724
3725 bool os::message_box(const char* title, const char* message) {
3726 int i;
3727 fdStream err(defaultStream::error_fd());
3728 for (i = 0; i < 78; i++) err.print_raw("=");
3729 err.cr();
3730 err.print_raw_cr(title);
3731 for (i = 0; i < 78; i++) err.print_raw("-");
3732 err.cr();
3733 err.print_raw_cr(message);
3734 for (i = 0; i < 78; i++) err.print_raw("=");
3735 err.cr();
3736
3737 char buf[16];
3738 // Prevent process from exiting upon "read error" without consuming all CPU
3739 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3740
3741 return buf[0] == 'y' || buf[0] == 'Y';
3742 }
3743
3744 int os::stat(const char *path, struct stat *sbuf) {
3745 char pathbuf[MAX_PATH];
3746 if (strlen(path) > MAX_PATH - 1) {
3747 errno = ENAMETOOLONG;
3748 return -1;
3749 }
3750 os::native_path(strcpy(pathbuf, path));
3751 return ::stat(pathbuf, sbuf);
3752 }
3753
3754 bool os::check_heap(bool force) {
3755 return true;
3756 }
3757
3758 // Is a (classpath) directory empty?
3759 bool os::dir_is_empty(const char* path) {
3760 DIR *dir = NULL;
3761 struct dirent *ptr;
3762
3763 dir = opendir(path);
3764 if (dir == NULL) return true;
3765
3766 // Scan the directory
3767 bool result = true;
3768 char buf[sizeof(struct dirent) + MAX_PATH];
3769 while (result && (ptr = ::readdir(dir)) != NULL) {
3770 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3771 result = false;
3772 }
3773 }
3774 closedir(dir);
3775 return result;
3776 }
3777
3778 // This code originates from JDK's sysOpen and open64_w
3779 // from src/solaris/hpi/src/system_md.c
3780
3781 int os::open(const char *path, int oflag, int mode) {
3782 if (strlen(path) > MAX_PATH - 1) {
3783 errno = ENAMETOOLONG;
3784 return -1;
3785 }
3786 int fd;
3787
3788 fd = ::open(path, oflag, mode);
3789 if (fd == -1) return -1;
3790
3791 // If the open succeeded, the file might still be a directory
3792 {
3793 struct stat buf;
3794 int ret = ::fstat(fd, &buf);
3795 int st_mode = buf.st_mode;
3796
3797 if (ret != -1) {
3798 if ((st_mode & S_IFMT) == S_IFDIR) {
3799 errno = EISDIR;
3800 ::close(fd);
3801 return -1;
3802 }
3803 } else {
3804 ::close(fd);
3805 return -1;
3806 }
3807 }
3808
3809 // All file descriptors that are opened in the JVM and not
3810 // specifically destined for a subprocess should have the
3811 // close-on-exec flag set. If we don't set it, then careless 3rd
3812 // party native code might fork and exec without closing all
3813 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3814 // UNIXProcess.c), and this in turn might:
3815 //
3816 // - cause end-of-file to fail to be detected on some file
3817 // descriptors, resulting in mysterious hangs, or
3818 //
3819 // - might cause an fopen in the subprocess to fail on a system
3820 // suffering from bug 1085341.
3821 //
3822 // (Yes, the default setting of the close-on-exec flag is a Unix
3823 // design flaw)
3824 //
3825 // See:
3826 // 1085341: 32-bit stdio routines should support file descriptors >255
3827 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3828 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3829 //
3830 #ifdef FD_CLOEXEC
3831 {
3832 int flags = ::fcntl(fd, F_GETFD);
3833 if (flags != -1) {
3834 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3835 }
3836 }
3837 #endif
3838
3839 return fd;
3840 }
3841
3842
3843 // create binary file, rewriting existing file if required
3844 int os::create_binary_file(const char* path, bool rewrite_existing) {
3845 int oflags = O_WRONLY | O_CREAT;
3846 if (!rewrite_existing) {
3847 oflags |= O_EXCL;
3848 }
3849 return ::open(path, oflags, S_IREAD | S_IWRITE);
3850 }
3851
3852 // return current position of file pointer
3853 jlong os::current_file_offset(int fd) {
3854 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3855 }
3856
3857 // move file pointer to the specified offset
3858 jlong os::seek_to_file_offset(int fd, jlong offset) {
3859 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3860 }
3861
3862 // This code originates from JDK's sysAvailable
3863 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3864
3865 int os::available(int fd, jlong *bytes) {
3866 jlong cur, end;
3867 int mode;
3868 struct stat buf;
3869
3870 if (::fstat(fd, &buf) >= 0) {
3871 mode = buf.st_mode;
3872 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3873 int n;
3874 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3875 *bytes = n;
3876 return 1;
3877 }
3878 }
3879 }
3880 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3881 return 0;
3882 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3883 return 0;
3884 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3885 return 0;
3886 }
3887 *bytes = end - cur;
3888 return 1;
3889 }
3890
3891 // Map a block of memory.
3892 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3893 char *addr, size_t bytes, bool read_only,
3894 bool allow_exec) {
3895 int prot;
3896 int flags;
3897
3898 if (read_only) {
3899 prot = PROT_READ;
3900 flags = MAP_SHARED;
3901 } else {
3902 prot = PROT_READ | PROT_WRITE;
3903 flags = MAP_PRIVATE;
3904 }
3905
3906 if (allow_exec) {
3907 prot |= PROT_EXEC;
3908 }
3909
3910 if (addr != NULL) {
3911 flags |= MAP_FIXED;
3912 }
3913
3914 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3915 fd, file_offset);
3916 if (mapped_address == MAP_FAILED) {
3917 return NULL;
3918 }
3919 return mapped_address;
3920 }
3921
3922
3923 // Remap a block of memory.
3924 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3925 char *addr, size_t bytes, bool read_only,
3926 bool allow_exec) {
3927 // same as map_memory() on this OS
3928 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3929 allow_exec);
3930 }
3931
3932
3933 // Unmap a block of memory.
3934 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3935 return munmap(addr, bytes) == 0;
3936 }
3937
3938 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3939 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3940 // of a thread.
3941 //
3942 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3943 // the fast estimate available on the platform.
3944
3945 jlong os::current_thread_cpu_time() {
3946 #ifdef __APPLE__
3947 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3948 #else
3949 Unimplemented();
3950 return 0;
3951 #endif
3952 }
3953
3954 jlong os::thread_cpu_time(Thread* thread) {
3955 #ifdef __APPLE__
3956 return os::thread_cpu_time(thread, true /* user + sys */);
3957 #else
3958 Unimplemented();
3959 return 0;
3960 #endif
3961 }
3962
3963 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3964 #ifdef __APPLE__
3965 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3966 #else
3967 Unimplemented();
3968 return 0;
3969 #endif
3970 }
3971
3972 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3973 #ifdef __APPLE__
3974 struct thread_basic_info tinfo;
3975 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3976 kern_return_t kr;
3977 thread_t mach_thread;
3978
3979 mach_thread = thread->osthread()->thread_id();
3980 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3981 if (kr != KERN_SUCCESS) {
3982 return -1;
3983 }
3984
3985 if (user_sys_cpu_time) {
3986 jlong nanos;
3987 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3988 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3989 return nanos;
3990 } else {
3991 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3992 }
3993 #else
3994 Unimplemented();
3995 return 0;
3996 #endif
3997 }
3998
3999
4000 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4001 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4002 info_ptr->may_skip_backward = false; // elapsed time not wall time
4003 info_ptr->may_skip_forward = false; // elapsed time not wall time
4004 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4005 }
4006
4007 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4008 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4009 info_ptr->may_skip_backward = false; // elapsed time not wall time
4010 info_ptr->may_skip_forward = false; // elapsed time not wall time
4011 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4012 }
4013
4014 bool os::is_thread_cpu_time_supported() {
4015 #ifdef __APPLE__
4016 return true;
4017 #else
4018 return false;
4019 #endif
4020 }
4021
4022 // System loadavg support. Returns -1 if load average cannot be obtained.
4023 // Bsd doesn't yet have a (official) notion of processor sets,
4024 // so just return the system wide load average.
4025 int os::loadavg(double loadavg[], int nelem) {
4026 return ::getloadavg(loadavg, nelem);
4027 }
4028
4029 void os::pause() {
4030 char filename[MAX_PATH];
4031 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4032 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4033 } else {
4034 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4035 }
4036
4037 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4038 if (fd != -1) {
4039 struct stat buf;
4040 ::close(fd);
4041 while (::stat(filename, &buf) == 0) {
4042 (void)::poll(NULL, 0, 100);
4043 }
4044 } else {
4045 jio_fprintf(stderr,
4046 "Could not open pause file '%s', continuing immediately.\n", filename);
4047 }
4048 }
4049
4050
4051 // Refer to the comments in os_solaris.cpp park-unpark. The next two
4052 // comment paragraphs are worth repeating here:
4053 //
4054 // Assumption:
4055 // Only one parker can exist on an event, which is why we allocate
4056 // them per-thread. Multiple unparkers can coexist.
4057 //
4058 // _Event serves as a restricted-range semaphore.
4059 // -1 : thread is blocked, i.e. there is a waiter
4060 // 0 : neutral: thread is running or ready,
4061 // could have been signaled after a wait started
4062 // 1 : signaled - thread is running or ready
4063 //
4064
4065 // utility to compute the abstime argument to timedwait:
4066 // millis is the relative timeout time
4067 // abstime will be the absolute timeout time
4068 // TODO: replace compute_abstime() with unpackTime()
4069
4070 static struct timespec* compute_abstime(struct timespec* abstime,
4071 jlong millis) {
4072 if (millis < 0) millis = 0;
4073 struct timeval now;
4074 int status = gettimeofday(&now, NULL);
4075 assert(status == 0, "gettimeofday");
4076 jlong seconds = millis / 1000;
4077 millis %= 1000;
4078 if (seconds > 50000000) { // see man cond_timedwait(3T)
4079 seconds = 50000000;
4080 }
4081 abstime->tv_sec = now.tv_sec + seconds;
4082 long usec = now.tv_usec + millis * 1000;
4083 if (usec >= 1000000) {
4084 abstime->tv_sec += 1;
4085 usec -= 1000000;
4086 }
4087 abstime->tv_nsec = usec * 1000;
4088 return abstime;
4089 }
4090
4091 void os::PlatformEvent::park() { // AKA "down()"
4092 // Transitions for _Event:
4093 // -1 => -1 : illegal
4094 // 1 => 0 : pass - return immediately
4095 // 0 => -1 : block; then set _Event to 0 before returning
4096
4097 // Invariant: Only the thread associated with the Event/PlatformEvent
4098 // may call park().
4099 // TODO: assert that _Assoc != NULL or _Assoc == Self
4100 assert(_nParked == 0, "invariant");
4101
4102 int v;
4103 for (;;) {
4104 v = _Event;
4105 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4106 }
4107 guarantee(v >= 0, "invariant");
4108 if (v == 0) {
4109 // Do this the hard way by blocking ...
4110 int status = pthread_mutex_lock(_mutex);
4111 assert_status(status == 0, status, "mutex_lock");
4112 guarantee(_nParked == 0, "invariant");
4113 ++_nParked;
4114 while (_Event < 0) {
4115 status = pthread_cond_wait(_cond, _mutex);
4116 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4117 // Treat this the same as if the wait was interrupted
4118 if (status == ETIMEDOUT) { status = EINTR; }
4119 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4120 }
4121 --_nParked;
4122
4123 _Event = 0;
4124 status = pthread_mutex_unlock(_mutex);
4125 assert_status(status == 0, status, "mutex_unlock");
4126 // Paranoia to ensure our locked and lock-free paths interact
4127 // correctly with each other.
4128 OrderAccess::fence();
4129 }
4130 guarantee(_Event >= 0, "invariant");
4131 }
4132
4133 int os::PlatformEvent::park(jlong millis) {
4134 // Transitions for _Event:
4135 // -1 => -1 : illegal
4136 // 1 => 0 : pass - return immediately
4137 // 0 => -1 : block; then set _Event to 0 before returning
4138
4139 guarantee(_nParked == 0, "invariant");
4140
4141 int v;
4142 for (;;) {
4143 v = _Event;
4144 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4145 }
4146 guarantee(v >= 0, "invariant");
4147 if (v != 0) return OS_OK;
4148
4149 // We do this the hard way, by blocking the thread.
4150 // Consider enforcing a minimum timeout value.
4151 struct timespec abst;
4152 compute_abstime(&abst, millis);
4153
4154 int ret = OS_TIMEOUT;
4155 int status = pthread_mutex_lock(_mutex);
4156 assert_status(status == 0, status, "mutex_lock");
4157 guarantee(_nParked == 0, "invariant");
4158 ++_nParked;
4159
4160 // Object.wait(timo) will return because of
4161 // (a) notification
4162 // (b) timeout
4163 // (c) thread.interrupt
4164 //
4165 // Thread.interrupt and object.notify{All} both call Event::set.
4166 // That is, we treat thread.interrupt as a special case of notification.
4167 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4168 // We assume all ETIME returns are valid.
4169 //
4170 // TODO: properly differentiate simultaneous notify+interrupt.
4171 // In that case, we should propagate the notify to another waiter.
4172
4173 while (_Event < 0) {
4174 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4175 assert_status(status == 0 || status == EINTR ||
4176 status == ETIMEDOUT,
4177 status, "cond_timedwait");
4178 if (!FilterSpuriousWakeups) break; // previous semantics
4179 if (status == ETIMEDOUT) break;
4180 // We consume and ignore EINTR and spurious wakeups.
4181 }
4182 --_nParked;
4183 if (_Event >= 0) {
4184 ret = OS_OK;
4185 }
4186 _Event = 0;
4187 status = pthread_mutex_unlock(_mutex);
4188 assert_status(status == 0, status, "mutex_unlock");
4189 assert(_nParked == 0, "invariant");
4190 // Paranoia to ensure our locked and lock-free paths interact
4191 // correctly with each other.
4192 OrderAccess::fence();
4193 return ret;
4194 }
4195
4196 void os::PlatformEvent::unpark() {
4197 // Transitions for _Event:
4198 // 0 => 1 : just return
4199 // 1 => 1 : just return
4200 // -1 => either 0 or 1; must signal target thread
4201 // That is, we can safely transition _Event from -1 to either
4202 // 0 or 1.
4203 // See also: "Semaphores in Plan 9" by Mullender & Cox
4204 //
4205 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4206 // that it will take two back-to-back park() calls for the owning
4207 // thread to block. This has the benefit of forcing a spurious return
4208 // from the first park() call after an unpark() call which will help
4209 // shake out uses of park() and unpark() without condition variables.
4210
4211 if (Atomic::xchg(1, &_Event) >= 0) return;
4212
4213 // Wait for the thread associated with the event to vacate
4214 int status = pthread_mutex_lock(_mutex);
4215 assert_status(status == 0, status, "mutex_lock");
4216 int AnyWaiters = _nParked;
4217 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4218 status = pthread_mutex_unlock(_mutex);
4219 assert_status(status == 0, status, "mutex_unlock");
4220 if (AnyWaiters != 0) {
4221 // Note that we signal() *after* dropping the lock for "immortal" Events.
4222 // This is safe and avoids a common class of futile wakeups. In rare
4223 // circumstances this can cause a thread to return prematurely from
4224 // cond_{timed}wait() but the spurious wakeup is benign and the victim
4225 // will simply re-test the condition and re-park itself.
4226 // This provides particular benefit if the underlying platform does not
4227 // provide wait morphing.
4228 status = pthread_cond_signal(_cond);
4229 assert_status(status == 0, status, "cond_signal");
4230 }
4231 }
4232
4233
4234 // JSR166
4235 // -------------------------------------------------------
4236
4237 // The solaris and bsd implementations of park/unpark are fairly
4238 // conservative for now, but can be improved. They currently use a
4239 // mutex/condvar pair, plus a a count.
4240 // Park decrements count if > 0, else does a condvar wait. Unpark
4241 // sets count to 1 and signals condvar. Only one thread ever waits
4242 // on the condvar. Contention seen when trying to park implies that someone
4243 // is unparking you, so don't wait. And spurious returns are fine, so there
4244 // is no need to track notifications.
4245
4246 #define MAX_SECS 100000000
4247
4248 // This code is common to bsd and solaris and will be moved to a
4249 // common place in dolphin.
4250 //
4251 // The passed in time value is either a relative time in nanoseconds
4252 // or an absolute time in milliseconds. Either way it has to be unpacked
4253 // into suitable seconds and nanoseconds components and stored in the
4254 // given timespec structure.
4255 // Given time is a 64-bit value and the time_t used in the timespec is only
4256 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4257 // overflow if times way in the future are given. Further on Solaris versions
4258 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4259 // number of seconds, in abstime, is less than current_time + 100,000,000.
4260 // As it will be 28 years before "now + 100000000" will overflow we can
4261 // ignore overflow and just impose a hard-limit on seconds using the value
4262 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4263 // years from "now".
4264
4265 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4266 assert(time > 0, "convertTime");
4267
4268 struct timeval now;
4269 int status = gettimeofday(&now, NULL);
4270 assert(status == 0, "gettimeofday");
4271
4272 time_t max_secs = now.tv_sec + MAX_SECS;
4273
4274 if (isAbsolute) {
4275 jlong secs = time / 1000;
4276 if (secs > max_secs) {
4277 absTime->tv_sec = max_secs;
4278 } else {
4279 absTime->tv_sec = secs;
4280 }
4281 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4282 } else {
4283 jlong secs = time / NANOSECS_PER_SEC;
4284 if (secs >= MAX_SECS) {
4285 absTime->tv_sec = max_secs;
4286 absTime->tv_nsec = 0;
4287 } else {
4288 absTime->tv_sec = now.tv_sec + secs;
4289 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4290 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4291 absTime->tv_nsec -= NANOSECS_PER_SEC;
4292 ++absTime->tv_sec; // note: this must be <= max_secs
4293 }
4294 }
4295 }
4296 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4297 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4298 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4299 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4300 }
4301
4302 void Parker::park(bool isAbsolute, jlong time) {
4303 // Ideally we'd do something useful while spinning, such
4304 // as calling unpackTime().
4305
4306 // Optional fast-path check:
4307 // Return immediately if a permit is available.
4308 // We depend on Atomic::xchg() having full barrier semantics
4309 // since we are doing a lock-free update to _counter.
4310 if (Atomic::xchg(0, &_counter) > 0) return;
4311
4312 Thread* thread = Thread::current();
4313 assert(thread->is_Java_thread(), "Must be JavaThread");
4314 JavaThread *jt = (JavaThread *)thread;
4315
4316 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4317 // Check interrupt before trying to wait
4318 if (Thread::is_interrupted(thread, false)) {
4319 return;
4320 }
4321
4322 // Next, demultiplex/decode time arguments
4323 struct timespec absTime;
4324 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4325 return;
4326 }
4327 if (time > 0) {
4328 unpackTime(&absTime, isAbsolute, time);
4329 }
4330
4331
4332 // Enter safepoint region
4333 // Beware of deadlocks such as 6317397.
4334 // The per-thread Parker:: mutex is a classic leaf-lock.
4335 // In particular a thread must never block on the Threads_lock while
4336 // holding the Parker:: mutex. If safepoints are pending both the
4337 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4338 ThreadBlockInVM tbivm(jt);
4339
4340 // Don't wait if cannot get lock since interference arises from
4341 // unblocking. Also. check interrupt before trying wait
4342 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4343 return;
4344 }
4345
4346 int status;
4347 if (_counter > 0) { // no wait needed
4348 _counter = 0;
4349 status = pthread_mutex_unlock(_mutex);
4350 assert_status(status == 0, status, "invariant");
4351 // Paranoia to ensure our locked and lock-free paths interact
4352 // correctly with each other and Java-level accesses.
4353 OrderAccess::fence();
4354 return;
4355 }
4356
4357 #ifdef ASSERT
4358 // Don't catch signals while blocked; let the running threads have the signals.
4359 // (This allows a debugger to break into the running thread.)
4360 sigset_t oldsigs;
4361 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4362 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4363 #endif
4364
4365 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4366 jt->set_suspend_equivalent();
4367 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4368
4369 if (time == 0) {
4370 status = pthread_cond_wait(_cond, _mutex);
4371 } else {
4372 status = pthread_cond_timedwait(_cond, _mutex, &absTime);
4373 }
4374 assert_status(status == 0 || status == EINTR ||
4375 status == ETIMEDOUT,
4376 status, "cond_timedwait");
4377
4378 #ifdef ASSERT
4379 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4380 #endif
4381
4382 _counter = 0;
4383 status = pthread_mutex_unlock(_mutex);
4384 assert_status(status == 0, status, "invariant");
4385 // Paranoia to ensure our locked and lock-free paths interact
4386 // correctly with each other and Java-level accesses.
4387 OrderAccess::fence();
4388
4389 // If externally suspended while waiting, re-suspend
4390 if (jt->handle_special_suspend_equivalent_condition()) {
4391 jt->java_suspend_self();
4392 }
4393 }
4394
4395 void Parker::unpark() {
4396 int status = pthread_mutex_lock(_mutex);
4397 assert_status(status == 0, status, "invariant");
4398 const int s = _counter;
4399 _counter = 1;
4400 status = pthread_mutex_unlock(_mutex);
4401 assert_status(status == 0, status, "invariant");
4402 if (s < 1) {
4403 status = pthread_cond_signal(_cond);
4404 assert_status(status == 0, status, "invariant");
4405 }
4406 }
4407
4408
4409 // Darwin has no "environ" in a dynamic library.
4410 #ifdef __APPLE__
4411 #include <crt_externs.h>
4412 #define environ (*_NSGetEnviron())
4413 #else
4414 extern char** environ;
4415 #endif
4416
4417 // Run the specified command in a separate process. Return its exit value,
4418 // or -1 on failure (e.g. can't fork a new process).
4419 // Unlike system(), this function can be called from signal handler. It
4420 // doesn't block SIGINT et al.
4421 int os::fork_and_exec(char* cmd) {
4422 const char * argv[4] = {"sh", "-c", cmd, NULL};
4423
4424 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4425 // pthread_atfork handlers and reset pthread library. All we need is a
4426 // separate process to execve. Make a direct syscall to fork process.
4427 // On IA64 there's no fork syscall, we have to use fork() and hope for
4428 // the best...
4429 pid_t pid = fork();
4430
4431 if (pid < 0) {
4432 // fork failed
4433 return -1;
4434
4435 } else if (pid == 0) {
4436 // child process
4437
4438 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4439 // first to kill every thread on the thread list. Because this list is
4440 // not reset by fork() (see notes above), execve() will instead kill
4441 // every thread in the parent process. We know this is the only thread
4442 // in the new process, so make a system call directly.
4443 // IA64 should use normal execve() from glibc to match the glibc fork()
4444 // above.
4445 execve("/bin/sh", (char* const*)argv, environ);
4446
4447 // execve failed
4448 _exit(-1);
4449
4450 } else {
4451 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4452 // care about the actual exit code, for now.
4453
4454 int status;
4455
4456 // Wait for the child process to exit. This returns immediately if
4457 // the child has already exited. */
4458 while (waitpid(pid, &status, 0) < 0) {
4459 switch (errno) {
4460 case ECHILD: return 0;
4461 case EINTR: break;
4462 default: return -1;
4463 }
4464 }
4465
4466 if (WIFEXITED(status)) {
4467 // The child exited normally; get its exit code.
4468 return WEXITSTATUS(status);
4469 } else if (WIFSIGNALED(status)) {
4470 // The child exited because of a signal
4471 // The best value to return is 0x80 + signal number,
4472 // because that is what all Unix shells do, and because
4473 // it allows callers to distinguish between process exit and
4474 // process death by signal.
4475 return 0x80 + WTERMSIG(status);
4476 } else {
4477 // Unknown exit code; pass it through
4478 return status;
4479 }
4480 }
4481 }
4482
4483 // is_headless_jre()
4484 //
4485 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4486 // in order to report if we are running in a headless jre
4487 //
4488 // Since JDK8 xawt/libmawt.so was moved into the same directory
4489 // as libawt.so, and renamed libawt_xawt.so
4490 //
4491 bool os::is_headless_jre() {
4492 #ifdef __APPLE__
4493 // We no longer build headless-only on Mac OS X
4494 return false;
4495 #else
4496 struct stat statbuf;
4497 char buf[MAXPATHLEN];
4498 char libmawtpath[MAXPATHLEN];
4499 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4500 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4501 char *p;
4502
4503 // Get path to libjvm.so
4504 os::jvm_path(buf, sizeof(buf));
4505
4506 // Get rid of libjvm.so
4507 p = strrchr(buf, '/');
4508 if (p == NULL) {
4509 return false;
4510 } else {
4511 *p = '\0';
4512 }
4513
4514 // Get rid of client or server
4515 p = strrchr(buf, '/');
4516 if (p == NULL) {
4517 return false;
4518 } else {
4519 *p = '\0';
4520 }
4521
4522 // check xawt/libmawt.so
4523 strcpy(libmawtpath, buf);
4524 strcat(libmawtpath, xawtstr);
4525 if (::stat(libmawtpath, &statbuf) == 0) return false;
4526
4527 // check libawt_xawt.so
4528 strcpy(libmawtpath, buf);
4529 strcat(libmawtpath, new_xawtstr);
4530 if (::stat(libmawtpath, &statbuf) == 0) return false;
4531
4532 return true;
4533 #endif
4534 }
4535
4536 // Get the default path to the core file
4537 // Returns the length of the string
4538 int os::get_core_path(char* buffer, size_t bufferSize) {
4539 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4540
4541 // Truncate if theoretical string was longer than bufferSize
4542 n = MIN2(n, (int)bufferSize);
4543
4544 return n;
4545 }
4546
4547 #ifndef PRODUCT
4548 void TestReserveMemorySpecial_test() {
4549 // No tests available for this platform
4550 }
4551 #endif
4552
4553 bool os::start_debugging(char *buf, int buflen) {
4554 int len = (int)strlen(buf);
4555 char *p = &buf[len];
4556
4557 jio_snprintf(p, buflen-len,
4558 "\n\n"
4559 "Do you want to debug the problem?\n\n"
4560 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
4561 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
4562 "Otherwise, press RETURN to abort...",
4563 os::current_process_id(), os::current_process_id(),
4564 os::current_thread_id(), os::current_thread_id());
4565
4566 bool yes = os::message_box("Unexpected Error", buf);
4567
4568 if (yes) {
4569 // yes, user asked VM to launch debugger
4570 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
4571 os::current_process_id(), os::current_process_id());
4572
4573 os::fork_and_exec(buf);
4574 yes = false;
4575 }
4576 return yes;
4577 }