Fri, 05 Apr 2013 10:38:08 -0700
Merge
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 // no precompiled headers
26 #include "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
104 #if defined(__FreeBSD__) || defined(__NetBSD__)
105 # include <elf.h>
106 #endif
108 #ifdef __APPLE__
109 # include <mach/mach.h> // semaphore_* API
110 # include <mach-o/dyld.h>
111 # include <sys/proc_info.h>
112 # include <objc/objc-auto.h>
113 #endif
115 #ifndef MAP_ANONYMOUS
116 #define MAP_ANONYMOUS MAP_ANON
117 #endif
119 #define MAX_PATH (2 * K)
121 // for timer info max values which include all bits
122 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
124 #define LARGEPAGES_BIT (1 << 6)
125 ////////////////////////////////////////////////////////////////////////////////
126 // global variables
127 julong os::Bsd::_physical_memory = 0;
130 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
131 pthread_t os::Bsd::_main_thread;
132 int os::Bsd::_page_size = -1;
134 static jlong initial_time_count=0;
136 static int clock_tics_per_sec = 100;
138 // For diagnostics to print a message once. see run_periodic_checks
139 static sigset_t check_signal_done;
140 static bool check_signals = true;
142 static pid_t _initial_pid = 0;
144 /* Signal number used to suspend/resume a thread */
146 /* do not use any signal number less than SIGSEGV, see 4355769 */
147 static int SR_signum = SIGUSR2;
148 sigset_t SR_sigset;
151 ////////////////////////////////////////////////////////////////////////////////
152 // utility functions
154 static int SR_initialize();
156 julong os::available_memory() {
157 return Bsd::available_memory();
158 }
160 julong os::Bsd::available_memory() {
161 // XXXBSD: this is just a stopgap implementation
162 return physical_memory() >> 2;
163 }
165 julong os::physical_memory() {
166 return Bsd::physical_memory();
167 }
169 ////////////////////////////////////////////////////////////////////////////////
170 // environment support
172 bool os::getenv(const char* name, char* buf, int len) {
173 const char* val = ::getenv(name);
174 if (val != NULL && strlen(val) < (size_t)len) {
175 strcpy(buf, val);
176 return true;
177 }
178 if (len > 0) buf[0] = 0; // return a null string
179 return false;
180 }
183 // Return true if user is running as root.
185 bool os::have_special_privileges() {
186 static bool init = false;
187 static bool privileges = false;
188 if (!init) {
189 privileges = (getuid() != geteuid()) || (getgid() != getegid());
190 init = true;
191 }
192 return privileges;
193 }
197 // Cpu architecture string
198 #if defined(ZERO)
199 static char cpu_arch[] = ZERO_LIBARCH;
200 #elif defined(IA64)
201 static char cpu_arch[] = "ia64";
202 #elif defined(IA32)
203 static char cpu_arch[] = "i386";
204 #elif defined(AMD64)
205 static char cpu_arch[] = "amd64";
206 #elif defined(ARM)
207 static char cpu_arch[] = "arm";
208 #elif defined(PPC)
209 static char cpu_arch[] = "ppc";
210 #elif defined(SPARC)
211 # ifdef _LP64
212 static char cpu_arch[] = "sparcv9";
213 # else
214 static char cpu_arch[] = "sparc";
215 # endif
216 #else
217 #error Add appropriate cpu_arch setting
218 #endif
220 // Compiler variant
221 #ifdef COMPILER2
222 #define COMPILER_VARIANT "server"
223 #else
224 #define COMPILER_VARIANT "client"
225 #endif
228 void os::Bsd::initialize_system_info() {
229 int mib[2];
230 size_t len;
231 int cpu_val;
232 julong mem_val;
234 /* get processors count via hw.ncpus sysctl */
235 mib[0] = CTL_HW;
236 mib[1] = HW_NCPU;
237 len = sizeof(cpu_val);
238 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
239 assert(len == sizeof(cpu_val), "unexpected data size");
240 set_processor_count(cpu_val);
241 }
242 else {
243 set_processor_count(1); // fallback
244 }
246 /* get physical memory via hw.memsize sysctl (hw.memsize is used
247 * since it returns a 64 bit value)
248 */
249 mib[0] = CTL_HW;
250 mib[1] = HW_MEMSIZE;
251 len = sizeof(mem_val);
252 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
253 assert(len == sizeof(mem_val), "unexpected data size");
254 _physical_memory = mem_val;
255 } else {
256 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
257 }
259 #ifdef __OpenBSD__
260 {
261 // limit _physical_memory memory view on OpenBSD since
262 // datasize rlimit restricts us anyway.
263 struct rlimit limits;
264 getrlimit(RLIMIT_DATA, &limits);
265 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
266 }
267 #endif
268 }
270 #ifdef __APPLE__
271 static const char *get_home() {
272 const char *home_dir = ::getenv("HOME");
273 if ((home_dir == NULL) || (*home_dir == '\0')) {
274 struct passwd *passwd_info = getpwuid(geteuid());
275 if (passwd_info != NULL) {
276 home_dir = passwd_info->pw_dir;
277 }
278 }
280 return home_dir;
281 }
282 #endif
284 void os::init_system_properties_values() {
285 // char arch[12];
286 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
288 // The next steps are taken in the product version:
289 //
290 // Obtain the JAVA_HOME value from the location of libjvm.so.
291 // This library should be located at:
292 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
293 //
294 // If "/jre/lib/" appears at the right place in the path, then we
295 // assume libjvm.so is installed in a JDK and we use this path.
296 //
297 // Otherwise exit with message: "Could not create the Java virtual machine."
298 //
299 // The following extra steps are taken in the debugging version:
300 //
301 // If "/jre/lib/" does NOT appear at the right place in the path
302 // instead of exit check for $JAVA_HOME environment variable.
303 //
304 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
305 // then we append a fake suffix "hotspot/libjvm.so" to this path so
306 // it looks like libjvm.so is installed there
307 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
308 //
309 // Otherwise exit.
310 //
311 // Important note: if the location of libjvm.so changes this
312 // code needs to be changed accordingly.
314 // The next few definitions allow the code to be verbatim:
315 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
316 #define getenv(n) ::getenv(n)
318 /*
319 * See ld(1):
320 * The linker uses the following search paths to locate required
321 * shared libraries:
322 * 1: ...
323 * ...
324 * 7: The default directories, normally /lib and /usr/lib.
325 */
326 #ifndef DEFAULT_LIBPATH
327 #define DEFAULT_LIBPATH "/lib:/usr/lib"
328 #endif
330 #define EXTENSIONS_DIR "/lib/ext"
331 #define ENDORSED_DIR "/lib/endorsed"
332 #define REG_DIR "/usr/java/packages"
334 #ifdef __APPLE__
335 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
336 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
337 const char *user_home_dir = get_home();
338 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
339 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
340 sizeof(SYS_EXTENSIONS_DIRS);
341 #endif
343 {
344 /* sysclasspath, java_home, dll_dir */
345 {
346 char *home_path;
347 char *dll_path;
348 char *pslash;
349 char buf[MAXPATHLEN];
350 os::jvm_path(buf, sizeof(buf));
352 // Found the full path to libjvm.so.
353 // Now cut the path to <java_home>/jre if we can.
354 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
355 pslash = strrchr(buf, '/');
356 if (pslash != NULL)
357 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
358 dll_path = malloc(strlen(buf) + 1);
359 if (dll_path == NULL)
360 return;
361 strcpy(dll_path, buf);
362 Arguments::set_dll_dir(dll_path);
364 if (pslash != NULL) {
365 pslash = strrchr(buf, '/');
366 if (pslash != NULL) {
367 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
368 #ifndef __APPLE__
369 pslash = strrchr(buf, '/');
370 if (pslash != NULL)
371 *pslash = '\0'; /* get rid of /lib */
372 #endif
373 }
374 }
376 home_path = malloc(strlen(buf) + 1);
377 if (home_path == NULL)
378 return;
379 strcpy(home_path, buf);
380 Arguments::set_java_home(home_path);
382 if (!set_boot_path('/', ':'))
383 return;
384 }
386 /*
387 * Where to look for native libraries
388 *
389 * Note: Due to a legacy implementation, most of the library path
390 * is set in the launcher. This was to accomodate linking restrictions
391 * on legacy Bsd implementations (which are no longer supported).
392 * Eventually, all the library path setting will be done here.
393 *
394 * However, to prevent the proliferation of improperly built native
395 * libraries, the new path component /usr/java/packages is added here.
396 * Eventually, all the library path setting will be done here.
397 */
398 {
399 char *ld_library_path;
401 /*
402 * Construct the invariant part of ld_library_path. Note that the
403 * space for the colon and the trailing null are provided by the
404 * nulls included by the sizeof operator (so actually we allocate
405 * a byte more than necessary).
406 */
407 #ifdef __APPLE__
408 ld_library_path = (char *) malloc(system_ext_size);
409 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
410 #else
411 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
412 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
413 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
414 #endif
416 /*
417 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
418 * should always exist (until the legacy problem cited above is
419 * addressed).
420 */
421 #ifdef __APPLE__
422 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
423 char *l = getenv("JAVA_LIBRARY_PATH");
424 if (l != NULL) {
425 char *t = ld_library_path;
426 /* That's +1 for the colon and +1 for the trailing '\0' */
427 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
428 sprintf(ld_library_path, "%s:%s", l, t);
429 free(t);
430 }
432 char *v = getenv("DYLD_LIBRARY_PATH");
433 #else
434 char *v = getenv("LD_LIBRARY_PATH");
435 #endif
436 if (v != NULL) {
437 char *t = ld_library_path;
438 /* That's +1 for the colon and +1 for the trailing '\0' */
439 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
440 sprintf(ld_library_path, "%s:%s", v, t);
441 free(t);
442 }
444 #ifdef __APPLE__
445 // Apple's Java6 has "." at the beginning of java.library.path.
446 // OpenJDK on Windows has "." at the end of java.library.path.
447 // OpenJDK on Linux and Solaris don't have "." in java.library.path
448 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
449 // "." is appended to the end of java.library.path. Yes, this
450 // could cause a change in behavior, but Apple's Java6 behavior
451 // can be achieved by putting "." at the beginning of the
452 // JAVA_LIBRARY_PATH environment variable.
453 {
454 char *t = ld_library_path;
455 // that's +3 for appending ":." and the trailing '\0'
456 ld_library_path = (char *) malloc(strlen(t) + 3);
457 sprintf(ld_library_path, "%s:%s", t, ".");
458 free(t);
459 }
460 #endif
462 Arguments::set_library_path(ld_library_path);
463 }
465 /*
466 * Extensions directories.
467 *
468 * Note that the space for the colon and the trailing null are provided
469 * by the nulls included by the sizeof operator (so actually one byte more
470 * than necessary is allocated).
471 */
472 {
473 #ifdef __APPLE__
474 char *buf = malloc(strlen(Arguments::get_java_home()) +
475 sizeof(EXTENSIONS_DIR) + system_ext_size);
476 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
477 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
478 #else
479 char *buf = malloc(strlen(Arguments::get_java_home()) +
480 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
481 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
482 Arguments::get_java_home());
483 #endif
485 Arguments::set_ext_dirs(buf);
486 }
488 /* Endorsed standards default directory. */
489 {
490 char * buf;
491 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
492 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
493 Arguments::set_endorsed_dirs(buf);
494 }
495 }
497 #ifdef __APPLE__
498 #undef SYS_EXTENSIONS_DIR
499 #endif
500 #undef malloc
501 #undef getenv
502 #undef EXTENSIONS_DIR
503 #undef ENDORSED_DIR
505 // Done
506 return;
507 }
509 ////////////////////////////////////////////////////////////////////////////////
510 // breakpoint support
512 void os::breakpoint() {
513 BREAKPOINT;
514 }
516 extern "C" void breakpoint() {
517 // use debugger to set breakpoint here
518 }
520 ////////////////////////////////////////////////////////////////////////////////
521 // signal support
523 debug_only(static bool signal_sets_initialized = false);
524 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
526 bool os::Bsd::is_sig_ignored(int sig) {
527 struct sigaction oact;
528 sigaction(sig, (struct sigaction*)NULL, &oact);
529 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
530 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
531 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
532 return true;
533 else
534 return false;
535 }
537 void os::Bsd::signal_sets_init() {
538 // Should also have an assertion stating we are still single-threaded.
539 assert(!signal_sets_initialized, "Already initialized");
540 // Fill in signals that are necessarily unblocked for all threads in
541 // the VM. Currently, we unblock the following signals:
542 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
543 // by -Xrs (=ReduceSignalUsage));
544 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
545 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
546 // the dispositions or masks wrt these signals.
547 // Programs embedding the VM that want to use the above signals for their
548 // own purposes must, at this time, use the "-Xrs" option to prevent
549 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
550 // (See bug 4345157, and other related bugs).
551 // In reality, though, unblocking these signals is really a nop, since
552 // these signals are not blocked by default.
553 sigemptyset(&unblocked_sigs);
554 sigemptyset(&allowdebug_blocked_sigs);
555 sigaddset(&unblocked_sigs, SIGILL);
556 sigaddset(&unblocked_sigs, SIGSEGV);
557 sigaddset(&unblocked_sigs, SIGBUS);
558 sigaddset(&unblocked_sigs, SIGFPE);
559 sigaddset(&unblocked_sigs, SR_signum);
561 if (!ReduceSignalUsage) {
562 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
563 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
564 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
565 }
566 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
567 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
568 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
569 }
570 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
571 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
572 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
573 }
574 }
575 // Fill in signals that are blocked by all but the VM thread.
576 sigemptyset(&vm_sigs);
577 if (!ReduceSignalUsage)
578 sigaddset(&vm_sigs, BREAK_SIGNAL);
579 debug_only(signal_sets_initialized = true);
581 }
583 // These are signals that are unblocked while a thread is running Java.
584 // (For some reason, they get blocked by default.)
585 sigset_t* os::Bsd::unblocked_signals() {
586 assert(signal_sets_initialized, "Not initialized");
587 return &unblocked_sigs;
588 }
590 // These are the signals that are blocked while a (non-VM) thread is
591 // running Java. Only the VM thread handles these signals.
592 sigset_t* os::Bsd::vm_signals() {
593 assert(signal_sets_initialized, "Not initialized");
594 return &vm_sigs;
595 }
597 // These are signals that are blocked during cond_wait to allow debugger in
598 sigset_t* os::Bsd::allowdebug_blocked_signals() {
599 assert(signal_sets_initialized, "Not initialized");
600 return &allowdebug_blocked_sigs;
601 }
603 void os::Bsd::hotspot_sigmask(Thread* thread) {
605 //Save caller's signal mask before setting VM signal mask
606 sigset_t caller_sigmask;
607 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
609 OSThread* osthread = thread->osthread();
610 osthread->set_caller_sigmask(caller_sigmask);
612 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
614 if (!ReduceSignalUsage) {
615 if (thread->is_VM_thread()) {
616 // Only the VM thread handles BREAK_SIGNAL ...
617 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
618 } else {
619 // ... all other threads block BREAK_SIGNAL
620 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
621 }
622 }
623 }
626 //////////////////////////////////////////////////////////////////////////////
627 // create new thread
629 static address highest_vm_reserved_address();
631 // check if it's safe to start a new thread
632 static bool _thread_safety_check(Thread* thread) {
633 return true;
634 }
636 #ifdef __APPLE__
637 // library handle for calling objc_registerThreadWithCollector()
638 // without static linking to the libobjc library
639 #define OBJC_LIB "/usr/lib/libobjc.dylib"
640 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
641 typedef void (*objc_registerThreadWithCollector_t)();
642 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
643 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
644 #endif
646 #ifdef __APPLE__
647 static uint64_t locate_unique_thread_id() {
648 // Additional thread_id used to correlate threads in SA
649 thread_identifier_info_data_t m_ident_info;
650 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
652 thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
653 (thread_info_t) &m_ident_info, &count);
654 return m_ident_info.thread_id;
655 }
656 #endif
658 // Thread start routine for all newly created threads
659 static void *java_start(Thread *thread) {
660 // Try to randomize the cache line index of hot stack frames.
661 // This helps when threads of the same stack traces evict each other's
662 // cache lines. The threads can be either from the same JVM instance, or
663 // from different JVM instances. The benefit is especially true for
664 // processors with hyperthreading technology.
665 static int counter = 0;
666 int pid = os::current_process_id();
667 alloca(((pid ^ counter++) & 7) * 128);
669 ThreadLocalStorage::set_thread(thread);
671 OSThread* osthread = thread->osthread();
672 Monitor* sync = osthread->startThread_lock();
674 // non floating stack BsdThreads needs extra check, see above
675 if (!_thread_safety_check(thread)) {
676 // notify parent thread
677 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
678 osthread->set_state(ZOMBIE);
679 sync->notify_all();
680 return NULL;
681 }
683 #ifdef __APPLE__
684 // thread_id is mach thread on macos
685 osthread->set_thread_id(::mach_thread_self());
686 osthread->set_unique_thread_id(locate_unique_thread_id());
687 #else
688 // thread_id is pthread_id on BSD
689 osthread->set_thread_id(::pthread_self());
690 #endif
691 // initialize signal mask for this thread
692 os::Bsd::hotspot_sigmask(thread);
694 // initialize floating point control register
695 os::Bsd::init_thread_fpu_state();
697 #ifdef __APPLE__
698 // register thread with objc gc
699 if (objc_registerThreadWithCollectorFunction != NULL) {
700 objc_registerThreadWithCollectorFunction();
701 }
702 #endif
704 // handshaking with parent thread
705 {
706 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
708 // notify parent thread
709 osthread->set_state(INITIALIZED);
710 sync->notify_all();
712 // wait until os::start_thread()
713 while (osthread->get_state() == INITIALIZED) {
714 sync->wait(Mutex::_no_safepoint_check_flag);
715 }
716 }
718 // call one more level start routine
719 thread->run();
721 return 0;
722 }
724 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
725 assert(thread->osthread() == NULL, "caller responsible");
727 // Allocate the OSThread object
728 OSThread* osthread = new OSThread(NULL, NULL);
729 if (osthread == NULL) {
730 return false;
731 }
733 // set the correct thread state
734 osthread->set_thread_type(thr_type);
736 // Initial state is ALLOCATED but not INITIALIZED
737 osthread->set_state(ALLOCATED);
739 thread->set_osthread(osthread);
741 // init thread attributes
742 pthread_attr_t attr;
743 pthread_attr_init(&attr);
744 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
746 // stack size
747 if (os::Bsd::supports_variable_stack_size()) {
748 // calculate stack size if it's not specified by caller
749 if (stack_size == 0) {
750 stack_size = os::Bsd::default_stack_size(thr_type);
752 switch (thr_type) {
753 case os::java_thread:
754 // Java threads use ThreadStackSize which default value can be
755 // changed with the flag -Xss
756 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
757 stack_size = JavaThread::stack_size_at_create();
758 break;
759 case os::compiler_thread:
760 if (CompilerThreadStackSize > 0) {
761 stack_size = (size_t)(CompilerThreadStackSize * K);
762 break;
763 } // else fall through:
764 // use VMThreadStackSize if CompilerThreadStackSize is not defined
765 case os::vm_thread:
766 case os::pgc_thread:
767 case os::cgc_thread:
768 case os::watcher_thread:
769 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
770 break;
771 }
772 }
774 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
775 pthread_attr_setstacksize(&attr, stack_size);
776 } else {
777 // let pthread_create() pick the default value.
778 }
780 ThreadState state;
782 {
783 pthread_t tid;
784 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
786 pthread_attr_destroy(&attr);
788 if (ret != 0) {
789 if (PrintMiscellaneous && (Verbose || WizardMode)) {
790 perror("pthread_create()");
791 }
792 // Need to clean up stuff we've allocated so far
793 thread->set_osthread(NULL);
794 delete osthread;
795 return false;
796 }
798 // Store pthread info into the OSThread
799 osthread->set_pthread_id(tid);
801 // Wait until child thread is either initialized or aborted
802 {
803 Monitor* sync_with_child = osthread->startThread_lock();
804 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
805 while ((state = osthread->get_state()) == ALLOCATED) {
806 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
807 }
808 }
810 }
812 // Aborted due to thread limit being reached
813 if (state == ZOMBIE) {
814 thread->set_osthread(NULL);
815 delete osthread;
816 return false;
817 }
819 // The thread is returned suspended (in state INITIALIZED),
820 // and is started higher up in the call chain
821 assert(state == INITIALIZED, "race condition");
822 return true;
823 }
825 /////////////////////////////////////////////////////////////////////////////
826 // attach existing thread
828 // bootstrap the main thread
829 bool os::create_main_thread(JavaThread* thread) {
830 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
831 return create_attached_thread(thread);
832 }
834 bool os::create_attached_thread(JavaThread* thread) {
835 #ifdef ASSERT
836 thread->verify_not_published();
837 #endif
839 // Allocate the OSThread object
840 OSThread* osthread = new OSThread(NULL, NULL);
842 if (osthread == NULL) {
843 return false;
844 }
846 // Store pthread info into the OSThread
847 #ifdef __APPLE__
848 osthread->set_thread_id(::mach_thread_self());
849 osthread->set_unique_thread_id(locate_unique_thread_id());
850 #else
851 osthread->set_thread_id(::pthread_self());
852 #endif
853 osthread->set_pthread_id(::pthread_self());
855 // initialize floating point control register
856 os::Bsd::init_thread_fpu_state();
858 // Initial thread state is RUNNABLE
859 osthread->set_state(RUNNABLE);
861 thread->set_osthread(osthread);
863 // initialize signal mask for this thread
864 // and save the caller's signal mask
865 os::Bsd::hotspot_sigmask(thread);
867 return true;
868 }
870 void os::pd_start_thread(Thread* thread) {
871 OSThread * osthread = thread->osthread();
872 assert(osthread->get_state() != INITIALIZED, "just checking");
873 Monitor* sync_with_child = osthread->startThread_lock();
874 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
875 sync_with_child->notify();
876 }
878 // Free Bsd resources related to the OSThread
879 void os::free_thread(OSThread* osthread) {
880 assert(osthread != NULL, "osthread not set");
882 if (Thread::current()->osthread() == osthread) {
883 // Restore caller's signal mask
884 sigset_t sigmask = osthread->caller_sigmask();
885 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
886 }
888 delete osthread;
889 }
891 //////////////////////////////////////////////////////////////////////////////
892 // thread local storage
894 int os::allocate_thread_local_storage() {
895 pthread_key_t key;
896 int rslt = pthread_key_create(&key, NULL);
897 assert(rslt == 0, "cannot allocate thread local storage");
898 return (int)key;
899 }
901 // Note: This is currently not used by VM, as we don't destroy TLS key
902 // on VM exit.
903 void os::free_thread_local_storage(int index) {
904 int rslt = pthread_key_delete((pthread_key_t)index);
905 assert(rslt == 0, "invalid index");
906 }
908 void os::thread_local_storage_at_put(int index, void* value) {
909 int rslt = pthread_setspecific((pthread_key_t)index, value);
910 assert(rslt == 0, "pthread_setspecific failed");
911 }
913 extern "C" Thread* get_thread() {
914 return ThreadLocalStorage::thread();
915 }
918 ////////////////////////////////////////////////////////////////////////////////
919 // time support
921 // Time since start-up in seconds to a fine granularity.
922 // Used by VMSelfDestructTimer and the MemProfiler.
923 double os::elapsedTime() {
925 return (double)(os::elapsed_counter()) * 0.000001;
926 }
928 jlong os::elapsed_counter() {
929 timeval time;
930 int status = gettimeofday(&time, NULL);
931 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
932 }
934 jlong os::elapsed_frequency() {
935 return (1000 * 1000);
936 }
938 // XXX: For now, code this as if BSD does not support vtime.
939 bool os::supports_vtime() { return false; }
940 bool os::enable_vtime() { return false; }
941 bool os::vtime_enabled() { return false; }
942 double os::elapsedVTime() {
943 // better than nothing, but not much
944 return elapsedTime();
945 }
947 jlong os::javaTimeMillis() {
948 timeval time;
949 int status = gettimeofday(&time, NULL);
950 assert(status != -1, "bsd error");
951 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
952 }
954 #ifndef CLOCK_MONOTONIC
955 #define CLOCK_MONOTONIC (1)
956 #endif
958 #ifdef __APPLE__
959 void os::Bsd::clock_init() {
960 // XXXDARWIN: Investigate replacement monotonic clock
961 }
962 #else
963 void os::Bsd::clock_init() {
964 struct timespec res;
965 struct timespec tp;
966 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
967 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
968 // yes, monotonic clock is supported
969 _clock_gettime = ::clock_gettime;
970 }
971 }
972 #endif
975 jlong os::javaTimeNanos() {
976 if (Bsd::supports_monotonic_clock()) {
977 struct timespec tp;
978 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
979 assert(status == 0, "gettime error");
980 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
981 return result;
982 } else {
983 timeval time;
984 int status = gettimeofday(&time, NULL);
985 assert(status != -1, "bsd error");
986 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
987 return 1000 * usecs;
988 }
989 }
991 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
992 if (Bsd::supports_monotonic_clock()) {
993 info_ptr->max_value = ALL_64_BITS;
995 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
996 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
997 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
998 } else {
999 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1000 info_ptr->max_value = ALL_64_BITS;
1002 // gettimeofday is a real time clock so it skips
1003 info_ptr->may_skip_backward = true;
1004 info_ptr->may_skip_forward = true;
1005 }
1007 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1008 }
1010 // Return the real, user, and system times in seconds from an
1011 // arbitrary fixed point in the past.
1012 bool os::getTimesSecs(double* process_real_time,
1013 double* process_user_time,
1014 double* process_system_time) {
1015 struct tms ticks;
1016 clock_t real_ticks = times(&ticks);
1018 if (real_ticks == (clock_t) (-1)) {
1019 return false;
1020 } else {
1021 double ticks_per_second = (double) clock_tics_per_sec;
1022 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1023 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1024 *process_real_time = ((double) real_ticks) / ticks_per_second;
1026 return true;
1027 }
1028 }
1031 char * os::local_time_string(char *buf, size_t buflen) {
1032 struct tm t;
1033 time_t long_time;
1034 time(&long_time);
1035 localtime_r(&long_time, &t);
1036 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1037 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1038 t.tm_hour, t.tm_min, t.tm_sec);
1039 return buf;
1040 }
1042 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1043 return localtime_r(clock, res);
1044 }
1046 ////////////////////////////////////////////////////////////////////////////////
1047 // runtime exit support
1049 // Note: os::shutdown() might be called very early during initialization, or
1050 // called from signal handler. Before adding something to os::shutdown(), make
1051 // sure it is async-safe and can handle partially initialized VM.
1052 void os::shutdown() {
1054 // allow PerfMemory to attempt cleanup of any persistent resources
1055 perfMemory_exit();
1057 // needs to remove object in file system
1058 AttachListener::abort();
1060 // flush buffered output, finish log files
1061 ostream_abort();
1063 // Check for abort hook
1064 abort_hook_t abort_hook = Arguments::abort_hook();
1065 if (abort_hook != NULL) {
1066 abort_hook();
1067 }
1069 }
1071 // Note: os::abort() might be called very early during initialization, or
1072 // called from signal handler. Before adding something to os::abort(), make
1073 // sure it is async-safe and can handle partially initialized VM.
1074 void os::abort(bool dump_core) {
1075 os::shutdown();
1076 if (dump_core) {
1077 #ifndef PRODUCT
1078 fdStream out(defaultStream::output_fd());
1079 out.print_raw("Current thread is ");
1080 char buf[16];
1081 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1082 out.print_raw_cr(buf);
1083 out.print_raw_cr("Dumping core ...");
1084 #endif
1085 ::abort(); // dump core
1086 }
1088 ::exit(1);
1089 }
1091 // Die immediately, no exit hook, no abort hook, no cleanup.
1092 void os::die() {
1093 // _exit() on BsdThreads only kills current thread
1094 ::abort();
1095 }
1097 // unused on bsd for now.
1098 void os::set_error_file(const char *logfile) {}
1101 // This method is a copy of JDK's sysGetLastErrorString
1102 // from src/solaris/hpi/src/system_md.c
1104 size_t os::lasterror(char *buf, size_t len) {
1106 if (errno == 0) return 0;
1108 const char *s = ::strerror(errno);
1109 size_t n = ::strlen(s);
1110 if (n >= len) {
1111 n = len - 1;
1112 }
1113 ::strncpy(buf, s, n);
1114 buf[n] = '\0';
1115 return n;
1116 }
1118 intx os::current_thread_id() {
1119 #ifdef __APPLE__
1120 return (intx)::mach_thread_self();
1121 #else
1122 return (intx)::pthread_self();
1123 #endif
1124 }
1125 int os::current_process_id() {
1127 // Under the old bsd thread library, bsd gives each thread
1128 // its own process id. Because of this each thread will return
1129 // a different pid if this method were to return the result
1130 // of getpid(2). Bsd provides no api that returns the pid
1131 // of the launcher thread for the vm. This implementation
1132 // returns a unique pid, the pid of the launcher thread
1133 // that starts the vm 'process'.
1135 // Under the NPTL, getpid() returns the same pid as the
1136 // launcher thread rather than a unique pid per thread.
1137 // Use gettid() if you want the old pre NPTL behaviour.
1139 // if you are looking for the result of a call to getpid() that
1140 // returns a unique pid for the calling thread, then look at the
1141 // OSThread::thread_id() method in osThread_bsd.hpp file
1143 return (int)(_initial_pid ? _initial_pid : getpid());
1144 }
1146 // DLL functions
1148 #define JNI_LIB_PREFIX "lib"
1149 #ifdef __APPLE__
1150 #define JNI_LIB_SUFFIX ".dylib"
1151 #else
1152 #define JNI_LIB_SUFFIX ".so"
1153 #endif
1155 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1157 // This must be hard coded because it's the system's temporary
1158 // directory not the java application's temp directory, ala java.io.tmpdir.
1159 #ifdef __APPLE__
1160 // macosx has a secure per-user temporary directory
1161 char temp_path_storage[PATH_MAX];
1162 const char* os::get_temp_directory() {
1163 static char *temp_path = NULL;
1164 if (temp_path == NULL) {
1165 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1166 if (pathSize == 0 || pathSize > PATH_MAX) {
1167 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1168 }
1169 temp_path = temp_path_storage;
1170 }
1171 return temp_path;
1172 }
1173 #else /* __APPLE__ */
1174 const char* os::get_temp_directory() { return "/tmp"; }
1175 #endif /* __APPLE__ */
1177 static bool file_exists(const char* filename) {
1178 struct stat statbuf;
1179 if (filename == NULL || strlen(filename) == 0) {
1180 return false;
1181 }
1182 return os::stat(filename, &statbuf) == 0;
1183 }
1185 bool os::dll_build_name(char* buffer, size_t buflen,
1186 const char* pname, const char* fname) {
1187 bool retval = false;
1188 // Copied from libhpi
1189 const size_t pnamelen = pname ? strlen(pname) : 0;
1191 // Return error on buffer overflow.
1192 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1193 return retval;
1194 }
1196 if (pnamelen == 0) {
1197 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1198 retval = true;
1199 } else if (strchr(pname, *os::path_separator()) != NULL) {
1200 int n;
1201 char** pelements = split_path(pname, &n);
1202 if (pelements == NULL) {
1203 return false;
1204 }
1205 for (int i = 0 ; i < n ; i++) {
1206 // Really shouldn't be NULL, but check can't hurt
1207 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1208 continue; // skip the empty path values
1209 }
1210 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1211 pelements[i], fname);
1212 if (file_exists(buffer)) {
1213 retval = true;
1214 break;
1215 }
1216 }
1217 // release the storage
1218 for (int i = 0 ; i < n ; i++) {
1219 if (pelements[i] != NULL) {
1220 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1221 }
1222 }
1223 if (pelements != NULL) {
1224 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1225 }
1226 } else {
1227 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1228 retval = true;
1229 }
1230 return retval;
1231 }
1233 const char* os::get_current_directory(char *buf, int buflen) {
1234 return getcwd(buf, buflen);
1235 }
1237 // check if addr is inside libjvm.so
1238 bool os::address_is_in_vm(address addr) {
1239 static address libjvm_base_addr;
1240 Dl_info dlinfo;
1242 if (libjvm_base_addr == NULL) {
1243 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1244 libjvm_base_addr = (address)dlinfo.dli_fbase;
1245 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1246 }
1248 if (dladdr((void *)addr, &dlinfo)) {
1249 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1250 }
1252 return false;
1253 }
1256 #define MACH_MAXSYMLEN 256
1258 bool os::dll_address_to_function_name(address addr, char *buf,
1259 int buflen, int *offset) {
1260 Dl_info dlinfo;
1261 char localbuf[MACH_MAXSYMLEN];
1263 // dladdr will find names of dynamic functions only, but does
1264 // it set dli_fbase with mach_header address when it "fails" ?
1265 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1266 if (buf != NULL) {
1267 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1268 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1269 }
1270 }
1271 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1272 return true;
1273 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1274 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1275 buf, buflen, offset, dlinfo.dli_fname)) {
1276 return true;
1277 }
1278 }
1280 // Handle non-dymanic manually:
1281 if (dlinfo.dli_fbase != NULL &&
1282 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1283 if(!Decoder::demangle(localbuf, buf, buflen)) {
1284 jio_snprintf(buf, buflen, "%s", localbuf);
1285 }
1286 return true;
1287 }
1288 if (buf != NULL) buf[0] = '\0';
1289 if (offset != NULL) *offset = -1;
1290 return false;
1291 }
1293 // ported from solaris version
1294 bool os::dll_address_to_library_name(address addr, char* buf,
1295 int buflen, int* offset) {
1296 Dl_info dlinfo;
1298 if (dladdr((void*)addr, &dlinfo)){
1299 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1300 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1301 return true;
1302 } else {
1303 if (buf) buf[0] = '\0';
1304 if (offset) *offset = -1;
1305 return false;
1306 }
1307 }
1309 // Loads .dll/.so and
1310 // in case of error it checks if .dll/.so was built for the
1311 // same architecture as Hotspot is running on
1313 #ifdef __APPLE__
1314 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1315 void * result= ::dlopen(filename, RTLD_LAZY);
1316 if (result != NULL) {
1317 // Successful loading
1318 return result;
1319 }
1321 // Read system error message into ebuf
1322 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1323 ebuf[ebuflen-1]='\0';
1325 return NULL;
1326 }
1327 #else
1328 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1329 {
1330 void * result= ::dlopen(filename, RTLD_LAZY);
1331 if (result != NULL) {
1332 // Successful loading
1333 return result;
1334 }
1336 Elf32_Ehdr elf_head;
1338 // Read system error message into ebuf
1339 // It may or may not be overwritten below
1340 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1341 ebuf[ebuflen-1]='\0';
1342 int diag_msg_max_length=ebuflen-strlen(ebuf);
1343 char* diag_msg_buf=ebuf+strlen(ebuf);
1345 if (diag_msg_max_length==0) {
1346 // No more space in ebuf for additional diagnostics message
1347 return NULL;
1348 }
1351 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1353 if (file_descriptor < 0) {
1354 // Can't open library, report dlerror() message
1355 return NULL;
1356 }
1358 bool failed_to_read_elf_head=
1359 (sizeof(elf_head)!=
1360 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1362 ::close(file_descriptor);
1363 if (failed_to_read_elf_head) {
1364 // file i/o error - report dlerror() msg
1365 return NULL;
1366 }
1368 typedef struct {
1369 Elf32_Half code; // Actual value as defined in elf.h
1370 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1371 char elf_class; // 32 or 64 bit
1372 char endianess; // MSB or LSB
1373 char* name; // String representation
1374 } arch_t;
1376 #ifndef EM_486
1377 #define EM_486 6 /* Intel 80486 */
1378 #endif
1380 #ifndef EM_MIPS_RS3_LE
1381 #define EM_MIPS_RS3_LE 10 /* MIPS */
1382 #endif
1384 #ifndef EM_PPC64
1385 #define EM_PPC64 21 /* PowerPC64 */
1386 #endif
1388 #ifndef EM_S390
1389 #define EM_S390 22 /* IBM System/390 */
1390 #endif
1392 #ifndef EM_IA_64
1393 #define EM_IA_64 50 /* HP/Intel IA-64 */
1394 #endif
1396 #ifndef EM_X86_64
1397 #define EM_X86_64 62 /* AMD x86-64 */
1398 #endif
1400 static const arch_t arch_array[]={
1401 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1402 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1403 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1404 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1405 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1406 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1407 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1408 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1409 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1410 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1411 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1412 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1413 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1414 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1415 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1416 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1417 };
1419 #if (defined IA32)
1420 static Elf32_Half running_arch_code=EM_386;
1421 #elif (defined AMD64)
1422 static Elf32_Half running_arch_code=EM_X86_64;
1423 #elif (defined IA64)
1424 static Elf32_Half running_arch_code=EM_IA_64;
1425 #elif (defined __sparc) && (defined _LP64)
1426 static Elf32_Half running_arch_code=EM_SPARCV9;
1427 #elif (defined __sparc) && (!defined _LP64)
1428 static Elf32_Half running_arch_code=EM_SPARC;
1429 #elif (defined __powerpc64__)
1430 static Elf32_Half running_arch_code=EM_PPC64;
1431 #elif (defined __powerpc__)
1432 static Elf32_Half running_arch_code=EM_PPC;
1433 #elif (defined ARM)
1434 static Elf32_Half running_arch_code=EM_ARM;
1435 #elif (defined S390)
1436 static Elf32_Half running_arch_code=EM_S390;
1437 #elif (defined ALPHA)
1438 static Elf32_Half running_arch_code=EM_ALPHA;
1439 #elif (defined MIPSEL)
1440 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1441 #elif (defined PARISC)
1442 static Elf32_Half running_arch_code=EM_PARISC;
1443 #elif (defined MIPS)
1444 static Elf32_Half running_arch_code=EM_MIPS;
1445 #elif (defined M68K)
1446 static Elf32_Half running_arch_code=EM_68K;
1447 #else
1448 #error Method os::dll_load requires that one of following is defined:\
1449 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1450 #endif
1452 // Identify compatability class for VM's architecture and library's architecture
1453 // Obtain string descriptions for architectures
1455 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1456 int running_arch_index=-1;
1458 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1459 if (running_arch_code == arch_array[i].code) {
1460 running_arch_index = i;
1461 }
1462 if (lib_arch.code == arch_array[i].code) {
1463 lib_arch.compat_class = arch_array[i].compat_class;
1464 lib_arch.name = arch_array[i].name;
1465 }
1466 }
1468 assert(running_arch_index != -1,
1469 "Didn't find running architecture code (running_arch_code) in arch_array");
1470 if (running_arch_index == -1) {
1471 // Even though running architecture detection failed
1472 // we may still continue with reporting dlerror() message
1473 return NULL;
1474 }
1476 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1477 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1478 return NULL;
1479 }
1481 #ifndef S390
1482 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1483 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1484 return NULL;
1485 }
1486 #endif // !S390
1488 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1489 if ( lib_arch.name!=NULL ) {
1490 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1491 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1492 lib_arch.name, arch_array[running_arch_index].name);
1493 } else {
1494 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1495 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1496 lib_arch.code,
1497 arch_array[running_arch_index].name);
1498 }
1499 }
1501 return NULL;
1502 }
1503 #endif /* !__APPLE__ */
1505 // XXX: Do we need a lock around this as per Linux?
1506 void* os::dll_lookup(void* handle, const char* name) {
1507 return dlsym(handle, name);
1508 }
1511 static bool _print_ascii_file(const char* filename, outputStream* st) {
1512 int fd = ::open(filename, O_RDONLY);
1513 if (fd == -1) {
1514 return false;
1515 }
1517 char buf[32];
1518 int bytes;
1519 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1520 st->print_raw(buf, bytes);
1521 }
1523 ::close(fd);
1525 return true;
1526 }
1528 void os::print_dll_info(outputStream *st) {
1529 st->print_cr("Dynamic libraries:");
1530 #ifdef RTLD_DI_LINKMAP
1531 Dl_info dli;
1532 void *handle;
1533 Link_map *map;
1534 Link_map *p;
1536 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
1537 st->print_cr("Error: Cannot print dynamic libraries.");
1538 return;
1539 }
1540 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1541 if (handle == NULL) {
1542 st->print_cr("Error: Cannot print dynamic libraries.");
1543 return;
1544 }
1545 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1546 if (map == NULL) {
1547 st->print_cr("Error: Cannot print dynamic libraries.");
1548 return;
1549 }
1551 while (map->l_prev != NULL)
1552 map = map->l_prev;
1554 while (map != NULL) {
1555 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1556 map = map->l_next;
1557 }
1559 dlclose(handle);
1560 #elif defined(__APPLE__)
1561 uint32_t count;
1562 uint32_t i;
1564 count = _dyld_image_count();
1565 for (i = 1; i < count; i++) {
1566 const char *name = _dyld_get_image_name(i);
1567 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1568 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1569 }
1570 #else
1571 st->print_cr("Error: Cannot print dynamic libraries.");
1572 #endif
1573 }
1575 void os::print_os_info_brief(outputStream* st) {
1576 st->print("Bsd");
1578 os::Posix::print_uname_info(st);
1579 }
1581 void os::print_os_info(outputStream* st) {
1582 st->print("OS:");
1583 st->print("Bsd");
1585 os::Posix::print_uname_info(st);
1587 os::Posix::print_rlimit_info(st);
1589 os::Posix::print_load_average(st);
1590 }
1592 void os::pd_print_cpu_info(outputStream* st) {
1593 // Nothing to do for now.
1594 }
1596 void os::print_memory_info(outputStream* st) {
1598 st->print("Memory:");
1599 st->print(" %dk page", os::vm_page_size()>>10);
1601 st->print(", physical " UINT64_FORMAT "k",
1602 os::physical_memory() >> 10);
1603 st->print("(" UINT64_FORMAT "k free)",
1604 os::available_memory() >> 10);
1605 st->cr();
1607 // meminfo
1608 st->print("\n/proc/meminfo:\n");
1609 _print_ascii_file("/proc/meminfo", st);
1610 st->cr();
1611 }
1613 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1614 // but they're the same for all the bsd arch that we support
1615 // and they're the same for solaris but there's no common place to put this.
1616 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1617 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1618 "ILL_COPROC", "ILL_BADSTK" };
1620 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1621 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1622 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1624 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1626 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1628 void os::print_siginfo(outputStream* st, void* siginfo) {
1629 st->print("siginfo:");
1631 const int buflen = 100;
1632 char buf[buflen];
1633 siginfo_t *si = (siginfo_t*)siginfo;
1634 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1635 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1636 st->print("si_errno=%s", buf);
1637 } else {
1638 st->print("si_errno=%d", si->si_errno);
1639 }
1640 const int c = si->si_code;
1641 assert(c > 0, "unexpected si_code");
1642 switch (si->si_signo) {
1643 case SIGILL:
1644 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1645 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1646 break;
1647 case SIGFPE:
1648 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1649 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1650 break;
1651 case SIGSEGV:
1652 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1653 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1654 break;
1655 case SIGBUS:
1656 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1657 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1658 break;
1659 default:
1660 st->print(", si_code=%d", si->si_code);
1661 // no si_addr
1662 }
1664 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1665 UseSharedSpaces) {
1666 FileMapInfo* mapinfo = FileMapInfo::current_info();
1667 if (mapinfo->is_in_shared_space(si->si_addr)) {
1668 st->print("\n\nError accessing class data sharing archive." \
1669 " Mapped file inaccessible during execution, " \
1670 " possible disk/network problem.");
1671 }
1672 }
1673 st->cr();
1674 }
1677 static void print_signal_handler(outputStream* st, int sig,
1678 char* buf, size_t buflen);
1680 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1681 st->print_cr("Signal Handlers:");
1682 print_signal_handler(st, SIGSEGV, buf, buflen);
1683 print_signal_handler(st, SIGBUS , buf, buflen);
1684 print_signal_handler(st, SIGFPE , buf, buflen);
1685 print_signal_handler(st, SIGPIPE, buf, buflen);
1686 print_signal_handler(st, SIGXFSZ, buf, buflen);
1687 print_signal_handler(st, SIGILL , buf, buflen);
1688 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1689 print_signal_handler(st, SR_signum, buf, buflen);
1690 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1691 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1692 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1693 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1694 }
1696 static char saved_jvm_path[MAXPATHLEN] = {0};
1698 // Find the full path to the current module, libjvm
1699 void os::jvm_path(char *buf, jint buflen) {
1700 // Error checking.
1701 if (buflen < MAXPATHLEN) {
1702 assert(false, "must use a large-enough buffer");
1703 buf[0] = '\0';
1704 return;
1705 }
1706 // Lazy resolve the path to current module.
1707 if (saved_jvm_path[0] != 0) {
1708 strcpy(buf, saved_jvm_path);
1709 return;
1710 }
1712 char dli_fname[MAXPATHLEN];
1713 bool ret = dll_address_to_library_name(
1714 CAST_FROM_FN_PTR(address, os::jvm_path),
1715 dli_fname, sizeof(dli_fname), NULL);
1716 assert(ret != 0, "cannot locate libjvm");
1717 char *rp = realpath(dli_fname, buf);
1718 if (rp == NULL)
1719 return;
1721 if (Arguments::created_by_gamma_launcher()) {
1722 // Support for the gamma launcher. Typical value for buf is
1723 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1724 // the right place in the string, then assume we are installed in a JDK and
1725 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1726 // construct a path to the JVM being overridden.
1728 const char *p = buf + strlen(buf) - 1;
1729 for (int count = 0; p > buf && count < 5; ++count) {
1730 for (--p; p > buf && *p != '/'; --p)
1731 /* empty */ ;
1732 }
1734 if (strncmp(p, "/jre/lib/", 9) != 0) {
1735 // Look for JAVA_HOME in the environment.
1736 char* java_home_var = ::getenv("JAVA_HOME");
1737 if (java_home_var != NULL && java_home_var[0] != 0) {
1738 char* jrelib_p;
1739 int len;
1741 // Check the current module name "libjvm"
1742 p = strrchr(buf, '/');
1743 assert(strstr(p, "/libjvm") == p, "invalid library name");
1745 rp = realpath(java_home_var, buf);
1746 if (rp == NULL)
1747 return;
1749 // determine if this is a legacy image or modules image
1750 // modules image doesn't have "jre" subdirectory
1751 len = strlen(buf);
1752 jrelib_p = buf + len;
1754 // Add the appropriate library subdir
1755 snprintf(jrelib_p, buflen-len, "/jre/lib");
1756 if (0 != access(buf, F_OK)) {
1757 snprintf(jrelib_p, buflen-len, "/lib");
1758 }
1760 // Add the appropriate client or server subdir
1761 len = strlen(buf);
1762 jrelib_p = buf + len;
1763 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1764 if (0 != access(buf, F_OK)) {
1765 snprintf(jrelib_p, buflen-len, "");
1766 }
1768 // If the path exists within JAVA_HOME, add the JVM library name
1769 // to complete the path to JVM being overridden. Otherwise fallback
1770 // to the path to the current library.
1771 if (0 == access(buf, F_OK)) {
1772 // Use current module name "libjvm"
1773 len = strlen(buf);
1774 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1775 } else {
1776 // Fall back to path of current library
1777 rp = realpath(dli_fname, buf);
1778 if (rp == NULL)
1779 return;
1780 }
1781 }
1782 }
1783 }
1785 strcpy(saved_jvm_path, buf);
1786 }
1788 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1789 // no prefix required, not even "_"
1790 }
1792 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1793 // no suffix required
1794 }
1796 ////////////////////////////////////////////////////////////////////////////////
1797 // sun.misc.Signal support
1799 static volatile jint sigint_count = 0;
1801 static void
1802 UserHandler(int sig, void *siginfo, void *context) {
1803 // 4511530 - sem_post is serialized and handled by the manager thread. When
1804 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1805 // don't want to flood the manager thread with sem_post requests.
1806 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1807 return;
1809 // Ctrl-C is pressed during error reporting, likely because the error
1810 // handler fails to abort. Let VM die immediately.
1811 if (sig == SIGINT && is_error_reported()) {
1812 os::die();
1813 }
1815 os::signal_notify(sig);
1816 }
1818 void* os::user_handler() {
1819 return CAST_FROM_FN_PTR(void*, UserHandler);
1820 }
1822 extern "C" {
1823 typedef void (*sa_handler_t)(int);
1824 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1825 }
1827 void* os::signal(int signal_number, void* handler) {
1828 struct sigaction sigAct, oldSigAct;
1830 sigfillset(&(sigAct.sa_mask));
1831 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1832 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1834 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1835 // -1 means registration failed
1836 return (void *)-1;
1837 }
1839 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1840 }
1842 void os::signal_raise(int signal_number) {
1843 ::raise(signal_number);
1844 }
1846 /*
1847 * The following code is moved from os.cpp for making this
1848 * code platform specific, which it is by its very nature.
1849 */
1851 // Will be modified when max signal is changed to be dynamic
1852 int os::sigexitnum_pd() {
1853 return NSIG;
1854 }
1856 // a counter for each possible signal value
1857 static volatile jint pending_signals[NSIG+1] = { 0 };
1859 // Bsd(POSIX) specific hand shaking semaphore.
1860 #ifdef __APPLE__
1861 static semaphore_t sig_sem;
1862 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1863 #define SEM_WAIT(sem) semaphore_wait(sem);
1864 #define SEM_POST(sem) semaphore_signal(sem);
1865 #else
1866 static sem_t sig_sem;
1867 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1868 #define SEM_WAIT(sem) sem_wait(&sem);
1869 #define SEM_POST(sem) sem_post(&sem);
1870 #endif
1872 void os::signal_init_pd() {
1873 // Initialize signal structures
1874 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1876 // Initialize signal semaphore
1877 ::SEM_INIT(sig_sem, 0);
1878 }
1880 void os::signal_notify(int sig) {
1881 Atomic::inc(&pending_signals[sig]);
1882 ::SEM_POST(sig_sem);
1883 }
1885 static int check_pending_signals(bool wait) {
1886 Atomic::store(0, &sigint_count);
1887 for (;;) {
1888 for (int i = 0; i < NSIG + 1; i++) {
1889 jint n = pending_signals[i];
1890 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1891 return i;
1892 }
1893 }
1894 if (!wait) {
1895 return -1;
1896 }
1897 JavaThread *thread = JavaThread::current();
1898 ThreadBlockInVM tbivm(thread);
1900 bool threadIsSuspended;
1901 do {
1902 thread->set_suspend_equivalent();
1903 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1904 ::SEM_WAIT(sig_sem);
1906 // were we externally suspended while we were waiting?
1907 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1908 if (threadIsSuspended) {
1909 //
1910 // The semaphore has been incremented, but while we were waiting
1911 // another thread suspended us. We don't want to continue running
1912 // while suspended because that would surprise the thread that
1913 // suspended us.
1914 //
1915 ::SEM_POST(sig_sem);
1917 thread->java_suspend_self();
1918 }
1919 } while (threadIsSuspended);
1920 }
1921 }
1923 int os::signal_lookup() {
1924 return check_pending_signals(false);
1925 }
1927 int os::signal_wait() {
1928 return check_pending_signals(true);
1929 }
1931 ////////////////////////////////////////////////////////////////////////////////
1932 // Virtual Memory
1934 int os::vm_page_size() {
1935 // Seems redundant as all get out
1936 assert(os::Bsd::page_size() != -1, "must call os::init");
1937 return os::Bsd::page_size();
1938 }
1940 // Solaris allocates memory by pages.
1941 int os::vm_allocation_granularity() {
1942 assert(os::Bsd::page_size() != -1, "must call os::init");
1943 return os::Bsd::page_size();
1944 }
1946 // Rationale behind this function:
1947 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1948 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1949 // samples for JITted code. Here we create private executable mapping over the code cache
1950 // and then we can use standard (well, almost, as mapping can change) way to provide
1951 // info for the reporting script by storing timestamp and location of symbol
1952 void bsd_wrap_code(char* base, size_t size) {
1953 static volatile jint cnt = 0;
1955 if (!UseOprofile) {
1956 return;
1957 }
1959 char buf[PATH_MAX + 1];
1960 int num = Atomic::add(1, &cnt);
1962 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1963 os::get_temp_directory(), os::current_process_id(), num);
1964 unlink(buf);
1966 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1968 if (fd != -1) {
1969 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1970 if (rv != (off_t)-1) {
1971 if (::write(fd, "", 1) == 1) {
1972 mmap(base, size,
1973 PROT_READ|PROT_WRITE|PROT_EXEC,
1974 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1975 }
1976 }
1977 ::close(fd);
1978 unlink(buf);
1979 }
1980 }
1982 // NOTE: Bsd kernel does not really reserve the pages for us.
1983 // All it does is to check if there are enough free pages
1984 // left at the time of mmap(). This could be a potential
1985 // problem.
1986 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1987 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1988 #ifdef __OpenBSD__
1989 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1990 return ::mprotect(addr, size, prot) == 0;
1991 #else
1992 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1993 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1994 return res != (uintptr_t) MAP_FAILED;
1995 #endif
1996 }
1999 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2000 bool exec) {
2001 return commit_memory(addr, size, exec);
2002 }
2004 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2005 }
2007 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2008 ::madvise(addr, bytes, MADV_DONTNEED);
2009 }
2011 void os::numa_make_global(char *addr, size_t bytes) {
2012 }
2014 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2015 }
2017 bool os::numa_topology_changed() { return false; }
2019 size_t os::numa_get_groups_num() {
2020 return 1;
2021 }
2023 int os::numa_get_group_id() {
2024 return 0;
2025 }
2027 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2028 if (size > 0) {
2029 ids[0] = 0;
2030 return 1;
2031 }
2032 return 0;
2033 }
2035 bool os::get_page_info(char *start, page_info* info) {
2036 return false;
2037 }
2039 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2040 return end;
2041 }
2044 bool os::pd_uncommit_memory(char* addr, size_t size) {
2045 #ifdef __OpenBSD__
2046 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2047 return ::mprotect(addr, size, PROT_NONE) == 0;
2048 #else
2049 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2050 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2051 return res != (uintptr_t) MAP_FAILED;
2052 #endif
2053 }
2055 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2056 return os::commit_memory(addr, size);
2057 }
2059 // If this is a growable mapping, remove the guard pages entirely by
2060 // munmap()ping them. If not, just call uncommit_memory().
2061 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2062 return os::uncommit_memory(addr, size);
2063 }
2065 static address _highest_vm_reserved_address = NULL;
2067 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2068 // at 'requested_addr'. If there are existing memory mappings at the same
2069 // location, however, they will be overwritten. If 'fixed' is false,
2070 // 'requested_addr' is only treated as a hint, the return value may or
2071 // may not start from the requested address. Unlike Bsd mmap(), this
2072 // function returns NULL to indicate failure.
2073 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2074 char * addr;
2075 int flags;
2077 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2078 if (fixed) {
2079 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2080 flags |= MAP_FIXED;
2081 }
2083 // Map uncommitted pages PROT_READ and PROT_WRITE, change access
2084 // to PROT_EXEC if executable when we commit the page.
2085 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
2086 flags, -1, 0);
2088 if (addr != MAP_FAILED) {
2089 // anon_mmap() should only get called during VM initialization,
2090 // don't need lock (actually we can skip locking even it can be called
2091 // from multiple threads, because _highest_vm_reserved_address is just a
2092 // hint about the upper limit of non-stack memory regions.)
2093 if ((address)addr + bytes > _highest_vm_reserved_address) {
2094 _highest_vm_reserved_address = (address)addr + bytes;
2095 }
2096 }
2098 return addr == MAP_FAILED ? NULL : addr;
2099 }
2101 // Don't update _highest_vm_reserved_address, because there might be memory
2102 // regions above addr + size. If so, releasing a memory region only creates
2103 // a hole in the address space, it doesn't help prevent heap-stack collision.
2104 //
2105 static int anon_munmap(char * addr, size_t size) {
2106 return ::munmap(addr, size) == 0;
2107 }
2109 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2110 size_t alignment_hint) {
2111 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2112 }
2114 bool os::pd_release_memory(char* addr, size_t size) {
2115 return anon_munmap(addr, size);
2116 }
2118 static address highest_vm_reserved_address() {
2119 return _highest_vm_reserved_address;
2120 }
2122 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2123 // Bsd wants the mprotect address argument to be page aligned.
2124 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2126 // According to SUSv3, mprotect() should only be used with mappings
2127 // established by mmap(), and mmap() always maps whole pages. Unaligned
2128 // 'addr' likely indicates problem in the VM (e.g. trying to change
2129 // protection of malloc'ed or statically allocated memory). Check the
2130 // caller if you hit this assert.
2131 assert(addr == bottom, "sanity check");
2133 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2134 return ::mprotect(bottom, size, prot) == 0;
2135 }
2137 // Set protections specified
2138 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2139 bool is_committed) {
2140 unsigned int p = 0;
2141 switch (prot) {
2142 case MEM_PROT_NONE: p = PROT_NONE; break;
2143 case MEM_PROT_READ: p = PROT_READ; break;
2144 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2145 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2146 default:
2147 ShouldNotReachHere();
2148 }
2149 // is_committed is unused.
2150 return bsd_mprotect(addr, bytes, p);
2151 }
2153 bool os::guard_memory(char* addr, size_t size) {
2154 return bsd_mprotect(addr, size, PROT_NONE);
2155 }
2157 bool os::unguard_memory(char* addr, size_t size) {
2158 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2159 }
2161 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2162 return false;
2163 }
2165 /*
2166 * Set the coredump_filter bits to include largepages in core dump (bit 6)
2167 *
2168 * From the coredump_filter documentation:
2169 *
2170 * - (bit 0) anonymous private memory
2171 * - (bit 1) anonymous shared memory
2172 * - (bit 2) file-backed private memory
2173 * - (bit 3) file-backed shared memory
2174 * - (bit 4) ELF header pages in file-backed private memory areas (it is
2175 * effective only if the bit 2 is cleared)
2176 * - (bit 5) hugetlb private memory
2177 * - (bit 6) hugetlb shared memory
2178 */
2179 static void set_coredump_filter(void) {
2180 FILE *f;
2181 long cdm;
2183 if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
2184 return;
2185 }
2187 if (fscanf(f, "%lx", &cdm) != 1) {
2188 fclose(f);
2189 return;
2190 }
2192 rewind(f);
2194 if ((cdm & LARGEPAGES_BIT) == 0) {
2195 cdm |= LARGEPAGES_BIT;
2196 fprintf(f, "%#lx", cdm);
2197 }
2199 fclose(f);
2200 }
2202 // Large page support
2204 static size_t _large_page_size = 0;
2206 void os::large_page_init() {
2207 }
2210 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2211 // "exec" is passed in but not used. Creating the shared image for
2212 // the code cache doesn't have an SHM_X executable permission to check.
2213 assert(UseLargePages && UseSHM, "only for SHM large pages");
2215 key_t key = IPC_PRIVATE;
2216 char *addr;
2218 bool warn_on_failure = UseLargePages &&
2219 (!FLAG_IS_DEFAULT(UseLargePages) ||
2220 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2221 );
2222 char msg[128];
2224 // Create a large shared memory region to attach to based on size.
2225 // Currently, size is the total size of the heap
2226 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2227 if (shmid == -1) {
2228 // Possible reasons for shmget failure:
2229 // 1. shmmax is too small for Java heap.
2230 // > check shmmax value: cat /proc/sys/kernel/shmmax
2231 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2232 // 2. not enough large page memory.
2233 // > check available large pages: cat /proc/meminfo
2234 // > increase amount of large pages:
2235 // echo new_value > /proc/sys/vm/nr_hugepages
2236 // Note 1: different Bsd may use different name for this property,
2237 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2238 // Note 2: it's possible there's enough physical memory available but
2239 // they are so fragmented after a long run that they can't
2240 // coalesce into large pages. Try to reserve large pages when
2241 // the system is still "fresh".
2242 if (warn_on_failure) {
2243 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2244 warning(msg);
2245 }
2246 return NULL;
2247 }
2249 // attach to the region
2250 addr = (char*)shmat(shmid, req_addr, 0);
2251 int err = errno;
2253 // Remove shmid. If shmat() is successful, the actual shared memory segment
2254 // will be deleted when it's detached by shmdt() or when the process
2255 // terminates. If shmat() is not successful this will remove the shared
2256 // segment immediately.
2257 shmctl(shmid, IPC_RMID, NULL);
2259 if ((intptr_t)addr == -1) {
2260 if (warn_on_failure) {
2261 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2262 warning(msg);
2263 }
2264 return NULL;
2265 }
2267 // The memory is committed
2268 address pc = CALLER_PC;
2269 MemTracker::record_virtual_memory_reserve((address)addr, bytes, pc);
2270 MemTracker::record_virtual_memory_commit((address)addr, bytes, pc);
2272 return addr;
2273 }
2275 bool os::release_memory_special(char* base, size_t bytes) {
2276 // detaching the SHM segment will also delete it, see reserve_memory_special()
2277 int rslt = shmdt(base);
2278 if (rslt == 0) {
2279 MemTracker::record_virtual_memory_uncommit((address)base, bytes);
2280 MemTracker::record_virtual_memory_release((address)base, bytes);
2281 return true;
2282 } else {
2283 return false;
2284 }
2286 }
2288 size_t os::large_page_size() {
2289 return _large_page_size;
2290 }
2292 // HugeTLBFS allows application to commit large page memory on demand;
2293 // with SysV SHM the entire memory region must be allocated as shared
2294 // memory.
2295 bool os::can_commit_large_page_memory() {
2296 return UseHugeTLBFS;
2297 }
2299 bool os::can_execute_large_page_memory() {
2300 return UseHugeTLBFS;
2301 }
2303 // Reserve memory at an arbitrary address, only if that area is
2304 // available (and not reserved for something else).
2306 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2307 const int max_tries = 10;
2308 char* base[max_tries];
2309 size_t size[max_tries];
2310 const size_t gap = 0x000000;
2312 // Assert only that the size is a multiple of the page size, since
2313 // that's all that mmap requires, and since that's all we really know
2314 // about at this low abstraction level. If we need higher alignment,
2315 // we can either pass an alignment to this method or verify alignment
2316 // in one of the methods further up the call chain. See bug 5044738.
2317 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2319 // Repeatedly allocate blocks until the block is allocated at the
2320 // right spot. Give up after max_tries. Note that reserve_memory() will
2321 // automatically update _highest_vm_reserved_address if the call is
2322 // successful. The variable tracks the highest memory address every reserved
2323 // by JVM. It is used to detect heap-stack collision if running with
2324 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2325 // space than needed, it could confuse the collision detecting code. To
2326 // solve the problem, save current _highest_vm_reserved_address and
2327 // calculate the correct value before return.
2328 address old_highest = _highest_vm_reserved_address;
2330 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2331 // if kernel honors the hint then we can return immediately.
2332 char * addr = anon_mmap(requested_addr, bytes, false);
2333 if (addr == requested_addr) {
2334 return requested_addr;
2335 }
2337 if (addr != NULL) {
2338 // mmap() is successful but it fails to reserve at the requested address
2339 anon_munmap(addr, bytes);
2340 }
2342 int i;
2343 for (i = 0; i < max_tries; ++i) {
2344 base[i] = reserve_memory(bytes);
2346 if (base[i] != NULL) {
2347 // Is this the block we wanted?
2348 if (base[i] == requested_addr) {
2349 size[i] = bytes;
2350 break;
2351 }
2353 // Does this overlap the block we wanted? Give back the overlapped
2354 // parts and try again.
2356 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2357 if (top_overlap >= 0 && top_overlap < bytes) {
2358 unmap_memory(base[i], top_overlap);
2359 base[i] += top_overlap;
2360 size[i] = bytes - top_overlap;
2361 } else {
2362 size_t bottom_overlap = base[i] + bytes - requested_addr;
2363 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2364 unmap_memory(requested_addr, bottom_overlap);
2365 size[i] = bytes - bottom_overlap;
2366 } else {
2367 size[i] = bytes;
2368 }
2369 }
2370 }
2371 }
2373 // Give back the unused reserved pieces.
2375 for (int j = 0; j < i; ++j) {
2376 if (base[j] != NULL) {
2377 unmap_memory(base[j], size[j]);
2378 }
2379 }
2381 if (i < max_tries) {
2382 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2383 return requested_addr;
2384 } else {
2385 _highest_vm_reserved_address = old_highest;
2386 return NULL;
2387 }
2388 }
2390 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2391 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2392 }
2394 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2395 // Solaris uses poll(), bsd uses park().
2396 // Poll() is likely a better choice, assuming that Thread.interrupt()
2397 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2398 // SIGSEGV, see 4355769.
2400 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2401 assert(thread == Thread::current(), "thread consistency check");
2403 ParkEvent * const slp = thread->_SleepEvent ;
2404 slp->reset() ;
2405 OrderAccess::fence() ;
2407 if (interruptible) {
2408 jlong prevtime = javaTimeNanos();
2410 for (;;) {
2411 if (os::is_interrupted(thread, true)) {
2412 return OS_INTRPT;
2413 }
2415 jlong newtime = javaTimeNanos();
2417 if (newtime - prevtime < 0) {
2418 // time moving backwards, should only happen if no monotonic clock
2419 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2420 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2421 } else {
2422 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2423 }
2425 if(millis <= 0) {
2426 return OS_OK;
2427 }
2429 prevtime = newtime;
2431 {
2432 assert(thread->is_Java_thread(), "sanity check");
2433 JavaThread *jt = (JavaThread *) thread;
2434 ThreadBlockInVM tbivm(jt);
2435 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2437 jt->set_suspend_equivalent();
2438 // cleared by handle_special_suspend_equivalent_condition() or
2439 // java_suspend_self() via check_and_wait_while_suspended()
2441 slp->park(millis);
2443 // were we externally suspended while we were waiting?
2444 jt->check_and_wait_while_suspended();
2445 }
2446 }
2447 } else {
2448 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2449 jlong prevtime = javaTimeNanos();
2451 for (;;) {
2452 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2453 // the 1st iteration ...
2454 jlong newtime = javaTimeNanos();
2456 if (newtime - prevtime < 0) {
2457 // time moving backwards, should only happen if no monotonic clock
2458 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2459 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2460 } else {
2461 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2462 }
2464 if(millis <= 0) break ;
2466 prevtime = newtime;
2467 slp->park(millis);
2468 }
2469 return OS_OK ;
2470 }
2471 }
2473 int os::naked_sleep() {
2474 // %% make the sleep time an integer flag. for now use 1 millisec.
2475 return os::sleep(Thread::current(), 1, false);
2476 }
2478 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2479 void os::infinite_sleep() {
2480 while (true) { // sleep forever ...
2481 ::sleep(100); // ... 100 seconds at a time
2482 }
2483 }
2485 // Used to convert frequent JVM_Yield() to nops
2486 bool os::dont_yield() {
2487 return DontYieldALot;
2488 }
2490 void os::yield() {
2491 sched_yield();
2492 }
2494 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2496 void os::yield_all(int attempts) {
2497 // Yields to all threads, including threads with lower priorities
2498 // Threads on Bsd are all with same priority. The Solaris style
2499 // os::yield_all() with nanosleep(1ms) is not necessary.
2500 sched_yield();
2501 }
2503 // Called from the tight loops to possibly influence time-sharing heuristics
2504 void os::loop_breaker(int attempts) {
2505 os::yield_all(attempts);
2506 }
2508 ////////////////////////////////////////////////////////////////////////////////
2509 // thread priority support
2511 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2512 // only supports dynamic priority, static priority must be zero. For real-time
2513 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2514 // However, for large multi-threaded applications, SCHED_RR is not only slower
2515 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2516 // of 5 runs - Sep 2005).
2517 //
2518 // The following code actually changes the niceness of kernel-thread/LWP. It
2519 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2520 // not the entire user process, and user level threads are 1:1 mapped to kernel
2521 // threads. It has always been the case, but could change in the future. For
2522 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2523 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2525 #if !defined(__APPLE__)
2526 int os::java_to_os_priority[CriticalPriority + 1] = {
2527 19, // 0 Entry should never be used
2529 0, // 1 MinPriority
2530 3, // 2
2531 6, // 3
2533 10, // 4
2534 15, // 5 NormPriority
2535 18, // 6
2537 21, // 7
2538 25, // 8
2539 28, // 9 NearMaxPriority
2541 31, // 10 MaxPriority
2543 31 // 11 CriticalPriority
2544 };
2545 #else
2546 /* Using Mach high-level priority assignments */
2547 int os::java_to_os_priority[CriticalPriority + 1] = {
2548 0, // 0 Entry should never be used (MINPRI_USER)
2550 27, // 1 MinPriority
2551 28, // 2
2552 29, // 3
2554 30, // 4
2555 31, // 5 NormPriority (BASEPRI_DEFAULT)
2556 32, // 6
2558 33, // 7
2559 34, // 8
2560 35, // 9 NearMaxPriority
2562 36, // 10 MaxPriority
2564 36 // 11 CriticalPriority
2565 };
2566 #endif
2568 static int prio_init() {
2569 if (ThreadPriorityPolicy == 1) {
2570 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2571 // if effective uid is not root. Perhaps, a more elegant way of doing
2572 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2573 if (geteuid() != 0) {
2574 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2575 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2576 }
2577 ThreadPriorityPolicy = 0;
2578 }
2579 }
2580 if (UseCriticalJavaThreadPriority) {
2581 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2582 }
2583 return 0;
2584 }
2586 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2587 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2589 #ifdef __OpenBSD__
2590 // OpenBSD pthread_setprio starves low priority threads
2591 return OS_OK;
2592 #elif defined(__FreeBSD__)
2593 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2594 #elif defined(__APPLE__) || defined(__NetBSD__)
2595 struct sched_param sp;
2596 int policy;
2597 pthread_t self = pthread_self();
2599 if (pthread_getschedparam(self, &policy, &sp) != 0)
2600 return OS_ERR;
2602 sp.sched_priority = newpri;
2603 if (pthread_setschedparam(self, policy, &sp) != 0)
2604 return OS_ERR;
2606 return OS_OK;
2607 #else
2608 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2609 return (ret == 0) ? OS_OK : OS_ERR;
2610 #endif
2611 }
2613 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2614 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2615 *priority_ptr = java_to_os_priority[NormPriority];
2616 return OS_OK;
2617 }
2619 errno = 0;
2620 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2621 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2622 #elif defined(__APPLE__) || defined(__NetBSD__)
2623 int policy;
2624 struct sched_param sp;
2626 pthread_getschedparam(pthread_self(), &policy, &sp);
2627 *priority_ptr = sp.sched_priority;
2628 #else
2629 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2630 #endif
2631 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2632 }
2634 // Hint to the underlying OS that a task switch would not be good.
2635 // Void return because it's a hint and can fail.
2636 void os::hint_no_preempt() {}
2638 ////////////////////////////////////////////////////////////////////////////////
2639 // suspend/resume support
2641 // the low-level signal-based suspend/resume support is a remnant from the
2642 // old VM-suspension that used to be for java-suspension, safepoints etc,
2643 // within hotspot. Now there is a single use-case for this:
2644 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2645 // that runs in the watcher thread.
2646 // The remaining code is greatly simplified from the more general suspension
2647 // code that used to be used.
2648 //
2649 // The protocol is quite simple:
2650 // - suspend:
2651 // - sends a signal to the target thread
2652 // - polls the suspend state of the osthread using a yield loop
2653 // - target thread signal handler (SR_handler) sets suspend state
2654 // and blocks in sigsuspend until continued
2655 // - resume:
2656 // - sets target osthread state to continue
2657 // - sends signal to end the sigsuspend loop in the SR_handler
2658 //
2659 // Note that the SR_lock plays no role in this suspend/resume protocol.
2660 //
2662 static void resume_clear_context(OSThread *osthread) {
2663 osthread->set_ucontext(NULL);
2664 osthread->set_siginfo(NULL);
2666 // notify the suspend action is completed, we have now resumed
2667 osthread->sr.clear_suspended();
2668 }
2670 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2671 osthread->set_ucontext(context);
2672 osthread->set_siginfo(siginfo);
2673 }
2675 //
2676 // Handler function invoked when a thread's execution is suspended or
2677 // resumed. We have to be careful that only async-safe functions are
2678 // called here (Note: most pthread functions are not async safe and
2679 // should be avoided.)
2680 //
2681 // Note: sigwait() is a more natural fit than sigsuspend() from an
2682 // interface point of view, but sigwait() prevents the signal hander
2683 // from being run. libpthread would get very confused by not having
2684 // its signal handlers run and prevents sigwait()'s use with the
2685 // mutex granting granting signal.
2686 //
2687 // Currently only ever called on the VMThread
2688 //
2689 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2690 // Save and restore errno to avoid confusing native code with EINTR
2691 // after sigsuspend.
2692 int old_errno = errno;
2694 Thread* thread = Thread::current();
2695 OSThread* osthread = thread->osthread();
2696 assert(thread->is_VM_thread(), "Must be VMThread");
2697 // read current suspend action
2698 int action = osthread->sr.suspend_action();
2699 if (action == os::Bsd::SuspendResume::SR_SUSPEND) {
2700 suspend_save_context(osthread, siginfo, context);
2702 // Notify the suspend action is about to be completed. do_suspend()
2703 // waits until SR_SUSPENDED is set and then returns. We will wait
2704 // here for a resume signal and that completes the suspend-other
2705 // action. do_suspend/do_resume is always called as a pair from
2706 // the same thread - so there are no races
2708 // notify the caller
2709 osthread->sr.set_suspended();
2711 sigset_t suspend_set; // signals for sigsuspend()
2713 // get current set of blocked signals and unblock resume signal
2714 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2715 sigdelset(&suspend_set, SR_signum);
2717 // wait here until we are resumed
2718 do {
2719 sigsuspend(&suspend_set);
2720 // ignore all returns until we get a resume signal
2721 } while (osthread->sr.suspend_action() != os::Bsd::SuspendResume::SR_CONTINUE);
2723 resume_clear_context(osthread);
2725 } else {
2726 assert(action == os::Bsd::SuspendResume::SR_CONTINUE, "unexpected sr action");
2727 // nothing special to do - just leave the handler
2728 }
2730 errno = old_errno;
2731 }
2734 static int SR_initialize() {
2735 struct sigaction act;
2736 char *s;
2737 /* Get signal number to use for suspend/resume */
2738 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2739 int sig = ::strtol(s, 0, 10);
2740 if (sig > 0 || sig < NSIG) {
2741 SR_signum = sig;
2742 }
2743 }
2745 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2746 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2748 sigemptyset(&SR_sigset);
2749 sigaddset(&SR_sigset, SR_signum);
2751 /* Set up signal handler for suspend/resume */
2752 act.sa_flags = SA_RESTART|SA_SIGINFO;
2753 act.sa_handler = (void (*)(int)) SR_handler;
2755 // SR_signum is blocked by default.
2756 // 4528190 - We also need to block pthread restart signal (32 on all
2757 // supported Bsd platforms). Note that BsdThreads need to block
2758 // this signal for all threads to work properly. So we don't have
2759 // to use hard-coded signal number when setting up the mask.
2760 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2762 if (sigaction(SR_signum, &act, 0) == -1) {
2763 return -1;
2764 }
2766 // Save signal flag
2767 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2768 return 0;
2769 }
2772 // returns true on success and false on error - really an error is fatal
2773 // but this seems the normal response to library errors
2774 static bool do_suspend(OSThread* osthread) {
2775 // mark as suspended and send signal
2776 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_SUSPEND);
2777 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2778 assert_status(status == 0, status, "pthread_kill");
2780 // check status and wait until notified of suspension
2781 if (status == 0) {
2782 for (int i = 0; !osthread->sr.is_suspended(); i++) {
2783 os::yield_all(i);
2784 }
2785 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2786 return true;
2787 }
2788 else {
2789 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2790 return false;
2791 }
2792 }
2794 static void do_resume(OSThread* osthread) {
2795 assert(osthread->sr.is_suspended(), "thread should be suspended");
2796 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_CONTINUE);
2798 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2799 assert_status(status == 0, status, "pthread_kill");
2800 // check status and wait unit notified of resumption
2801 if (status == 0) {
2802 for (int i = 0; osthread->sr.is_suspended(); i++) {
2803 os::yield_all(i);
2804 }
2805 }
2806 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2807 }
2809 ////////////////////////////////////////////////////////////////////////////////
2810 // interrupt support
2812 void os::interrupt(Thread* thread) {
2813 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2814 "possibility of dangling Thread pointer");
2816 OSThread* osthread = thread->osthread();
2818 if (!osthread->interrupted()) {
2819 osthread->set_interrupted(true);
2820 // More than one thread can get here with the same value of osthread,
2821 // resulting in multiple notifications. We do, however, want the store
2822 // to interrupted() to be visible to other threads before we execute unpark().
2823 OrderAccess::fence();
2824 ParkEvent * const slp = thread->_SleepEvent ;
2825 if (slp != NULL) slp->unpark() ;
2826 }
2828 // For JSR166. Unpark even if interrupt status already was set
2829 if (thread->is_Java_thread())
2830 ((JavaThread*)thread)->parker()->unpark();
2832 ParkEvent * ev = thread->_ParkEvent ;
2833 if (ev != NULL) ev->unpark() ;
2835 }
2837 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2838 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2839 "possibility of dangling Thread pointer");
2841 OSThread* osthread = thread->osthread();
2843 bool interrupted = osthread->interrupted();
2845 if (interrupted && clear_interrupted) {
2846 osthread->set_interrupted(false);
2847 // consider thread->_SleepEvent->reset() ... optional optimization
2848 }
2850 return interrupted;
2851 }
2853 ///////////////////////////////////////////////////////////////////////////////////
2854 // signal handling (except suspend/resume)
2856 // This routine may be used by user applications as a "hook" to catch signals.
2857 // The user-defined signal handler must pass unrecognized signals to this
2858 // routine, and if it returns true (non-zero), then the signal handler must
2859 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2860 // routine will never retun false (zero), but instead will execute a VM panic
2861 // routine kill the process.
2862 //
2863 // If this routine returns false, it is OK to call it again. This allows
2864 // the user-defined signal handler to perform checks either before or after
2865 // the VM performs its own checks. Naturally, the user code would be making
2866 // a serious error if it tried to handle an exception (such as a null check
2867 // or breakpoint) that the VM was generating for its own correct operation.
2868 //
2869 // This routine may recognize any of the following kinds of signals:
2870 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2871 // It should be consulted by handlers for any of those signals.
2872 //
2873 // The caller of this routine must pass in the three arguments supplied
2874 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2875 // field of the structure passed to sigaction(). This routine assumes that
2876 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2877 //
2878 // Note that the VM will print warnings if it detects conflicting signal
2879 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2880 //
2881 extern "C" JNIEXPORT int
2882 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2883 void* ucontext, int abort_if_unrecognized);
2885 void signalHandler(int sig, siginfo_t* info, void* uc) {
2886 assert(info != NULL && uc != NULL, "it must be old kernel");
2887 int orig_errno = errno; // Preserve errno value over signal handler.
2888 JVM_handle_bsd_signal(sig, info, uc, true);
2889 errno = orig_errno;
2890 }
2893 // This boolean allows users to forward their own non-matching signals
2894 // to JVM_handle_bsd_signal, harmlessly.
2895 bool os::Bsd::signal_handlers_are_installed = false;
2897 // For signal-chaining
2898 struct sigaction os::Bsd::sigact[MAXSIGNUM];
2899 unsigned int os::Bsd::sigs = 0;
2900 bool os::Bsd::libjsig_is_loaded = false;
2901 typedef struct sigaction *(*get_signal_t)(int);
2902 get_signal_t os::Bsd::get_signal_action = NULL;
2904 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2905 struct sigaction *actp = NULL;
2907 if (libjsig_is_loaded) {
2908 // Retrieve the old signal handler from libjsig
2909 actp = (*get_signal_action)(sig);
2910 }
2911 if (actp == NULL) {
2912 // Retrieve the preinstalled signal handler from jvm
2913 actp = get_preinstalled_handler(sig);
2914 }
2916 return actp;
2917 }
2919 static bool call_chained_handler(struct sigaction *actp, int sig,
2920 siginfo_t *siginfo, void *context) {
2921 // Call the old signal handler
2922 if (actp->sa_handler == SIG_DFL) {
2923 // It's more reasonable to let jvm treat it as an unexpected exception
2924 // instead of taking the default action.
2925 return false;
2926 } else if (actp->sa_handler != SIG_IGN) {
2927 if ((actp->sa_flags & SA_NODEFER) == 0) {
2928 // automaticlly block the signal
2929 sigaddset(&(actp->sa_mask), sig);
2930 }
2932 sa_handler_t hand;
2933 sa_sigaction_t sa;
2934 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2935 // retrieve the chained handler
2936 if (siginfo_flag_set) {
2937 sa = actp->sa_sigaction;
2938 } else {
2939 hand = actp->sa_handler;
2940 }
2942 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2943 actp->sa_handler = SIG_DFL;
2944 }
2946 // try to honor the signal mask
2947 sigset_t oset;
2948 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2950 // call into the chained handler
2951 if (siginfo_flag_set) {
2952 (*sa)(sig, siginfo, context);
2953 } else {
2954 (*hand)(sig);
2955 }
2957 // restore the signal mask
2958 pthread_sigmask(SIG_SETMASK, &oset, 0);
2959 }
2960 // Tell jvm's signal handler the signal is taken care of.
2961 return true;
2962 }
2964 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2965 bool chained = false;
2966 // signal-chaining
2967 if (UseSignalChaining) {
2968 struct sigaction *actp = get_chained_signal_action(sig);
2969 if (actp != NULL) {
2970 chained = call_chained_handler(actp, sig, siginfo, context);
2971 }
2972 }
2973 return chained;
2974 }
2976 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
2977 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
2978 return &sigact[sig];
2979 }
2980 return NULL;
2981 }
2983 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
2984 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2985 sigact[sig] = oldAct;
2986 sigs |= (unsigned int)1 << sig;
2987 }
2989 // for diagnostic
2990 int os::Bsd::sigflags[MAXSIGNUM];
2992 int os::Bsd::get_our_sigflags(int sig) {
2993 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2994 return sigflags[sig];
2995 }
2997 void os::Bsd::set_our_sigflags(int sig, int flags) {
2998 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
2999 sigflags[sig] = flags;
3000 }
3002 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3003 // Check for overwrite.
3004 struct sigaction oldAct;
3005 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3007 void* oldhand = oldAct.sa_sigaction
3008 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3009 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3010 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3011 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3012 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3013 if (AllowUserSignalHandlers || !set_installed) {
3014 // Do not overwrite; user takes responsibility to forward to us.
3015 return;
3016 } else if (UseSignalChaining) {
3017 // save the old handler in jvm
3018 save_preinstalled_handler(sig, oldAct);
3019 // libjsig also interposes the sigaction() call below and saves the
3020 // old sigaction on it own.
3021 } else {
3022 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3023 "%#lx for signal %d.", (long)oldhand, sig));
3024 }
3025 }
3027 struct sigaction sigAct;
3028 sigfillset(&(sigAct.sa_mask));
3029 sigAct.sa_handler = SIG_DFL;
3030 if (!set_installed) {
3031 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3032 } else {
3033 sigAct.sa_sigaction = signalHandler;
3034 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3035 }
3036 // Save flags, which are set by ours
3037 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3038 sigflags[sig] = sigAct.sa_flags;
3040 int ret = sigaction(sig, &sigAct, &oldAct);
3041 assert(ret == 0, "check");
3043 void* oldhand2 = oldAct.sa_sigaction
3044 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3045 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3046 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3047 }
3049 // install signal handlers for signals that HotSpot needs to
3050 // handle in order to support Java-level exception handling.
3052 void os::Bsd::install_signal_handlers() {
3053 if (!signal_handlers_are_installed) {
3054 signal_handlers_are_installed = true;
3056 // signal-chaining
3057 typedef void (*signal_setting_t)();
3058 signal_setting_t begin_signal_setting = NULL;
3059 signal_setting_t end_signal_setting = NULL;
3060 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3061 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3062 if (begin_signal_setting != NULL) {
3063 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3064 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3065 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3066 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3067 libjsig_is_loaded = true;
3068 assert(UseSignalChaining, "should enable signal-chaining");
3069 }
3070 if (libjsig_is_loaded) {
3071 // Tell libjsig jvm is setting signal handlers
3072 (*begin_signal_setting)();
3073 }
3075 set_signal_handler(SIGSEGV, true);
3076 set_signal_handler(SIGPIPE, true);
3077 set_signal_handler(SIGBUS, true);
3078 set_signal_handler(SIGILL, true);
3079 set_signal_handler(SIGFPE, true);
3080 set_signal_handler(SIGXFSZ, true);
3082 #if defined(__APPLE__)
3083 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3084 // signals caught and handled by the JVM. To work around this, we reset the mach task
3085 // signal handler that's placed on our process by CrashReporter. This disables
3086 // CrashReporter-based reporting.
3087 //
3088 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3089 // on caught fatal signals.
3090 //
3091 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3092 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3093 // exception handling, while leaving the standard BSD signal handlers functional.
3094 kern_return_t kr;
3095 kr = task_set_exception_ports(mach_task_self(),
3096 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3097 MACH_PORT_NULL,
3098 EXCEPTION_STATE_IDENTITY,
3099 MACHINE_THREAD_STATE);
3101 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3102 #endif
3104 if (libjsig_is_loaded) {
3105 // Tell libjsig jvm finishes setting signal handlers
3106 (*end_signal_setting)();
3107 }
3109 // We don't activate signal checker if libjsig is in place, we trust ourselves
3110 // and if UserSignalHandler is installed all bets are off
3111 if (CheckJNICalls) {
3112 if (libjsig_is_loaded) {
3113 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3114 check_signals = false;
3115 }
3116 if (AllowUserSignalHandlers) {
3117 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3118 check_signals = false;
3119 }
3120 }
3121 }
3122 }
3125 /////
3126 // glibc on Bsd platform uses non-documented flag
3127 // to indicate, that some special sort of signal
3128 // trampoline is used.
3129 // We will never set this flag, and we should
3130 // ignore this flag in our diagnostic
3131 #ifdef SIGNIFICANT_SIGNAL_MASK
3132 #undef SIGNIFICANT_SIGNAL_MASK
3133 #endif
3134 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3136 static const char* get_signal_handler_name(address handler,
3137 char* buf, int buflen) {
3138 int offset;
3139 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3140 if (found) {
3141 // skip directory names
3142 const char *p1, *p2;
3143 p1 = buf;
3144 size_t len = strlen(os::file_separator());
3145 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3146 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3147 } else {
3148 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3149 }
3150 return buf;
3151 }
3153 static void print_signal_handler(outputStream* st, int sig,
3154 char* buf, size_t buflen) {
3155 struct sigaction sa;
3157 sigaction(sig, NULL, &sa);
3159 // See comment for SIGNIFICANT_SIGNAL_MASK define
3160 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3162 st->print("%s: ", os::exception_name(sig, buf, buflen));
3164 address handler = (sa.sa_flags & SA_SIGINFO)
3165 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3166 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3168 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3169 st->print("SIG_DFL");
3170 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3171 st->print("SIG_IGN");
3172 } else {
3173 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3174 }
3176 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3178 address rh = VMError::get_resetted_sighandler(sig);
3179 // May be, handler was resetted by VMError?
3180 if(rh != NULL) {
3181 handler = rh;
3182 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3183 }
3185 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3187 // Check: is it our handler?
3188 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3189 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3190 // It is our signal handler
3191 // check for flags, reset system-used one!
3192 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3193 st->print(
3194 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3195 os::Bsd::get_our_sigflags(sig));
3196 }
3197 }
3198 st->cr();
3199 }
3202 #define DO_SIGNAL_CHECK(sig) \
3203 if (!sigismember(&check_signal_done, sig)) \
3204 os::Bsd::check_signal_handler(sig)
3206 // This method is a periodic task to check for misbehaving JNI applications
3207 // under CheckJNI, we can add any periodic checks here
3209 void os::run_periodic_checks() {
3211 if (check_signals == false) return;
3213 // SEGV and BUS if overridden could potentially prevent
3214 // generation of hs*.log in the event of a crash, debugging
3215 // such a case can be very challenging, so we absolutely
3216 // check the following for a good measure:
3217 DO_SIGNAL_CHECK(SIGSEGV);
3218 DO_SIGNAL_CHECK(SIGILL);
3219 DO_SIGNAL_CHECK(SIGFPE);
3220 DO_SIGNAL_CHECK(SIGBUS);
3221 DO_SIGNAL_CHECK(SIGPIPE);
3222 DO_SIGNAL_CHECK(SIGXFSZ);
3225 // ReduceSignalUsage allows the user to override these handlers
3226 // see comments at the very top and jvm_solaris.h
3227 if (!ReduceSignalUsage) {
3228 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3229 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3230 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3231 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3232 }
3234 DO_SIGNAL_CHECK(SR_signum);
3235 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3236 }
3238 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3240 static os_sigaction_t os_sigaction = NULL;
3242 void os::Bsd::check_signal_handler(int sig) {
3243 char buf[O_BUFLEN];
3244 address jvmHandler = NULL;
3247 struct sigaction act;
3248 if (os_sigaction == NULL) {
3249 // only trust the default sigaction, in case it has been interposed
3250 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3251 if (os_sigaction == NULL) return;
3252 }
3254 os_sigaction(sig, (struct sigaction*)NULL, &act);
3257 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3259 address thisHandler = (act.sa_flags & SA_SIGINFO)
3260 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3261 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3264 switch(sig) {
3265 case SIGSEGV:
3266 case SIGBUS:
3267 case SIGFPE:
3268 case SIGPIPE:
3269 case SIGILL:
3270 case SIGXFSZ:
3271 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3272 break;
3274 case SHUTDOWN1_SIGNAL:
3275 case SHUTDOWN2_SIGNAL:
3276 case SHUTDOWN3_SIGNAL:
3277 case BREAK_SIGNAL:
3278 jvmHandler = (address)user_handler();
3279 break;
3281 case INTERRUPT_SIGNAL:
3282 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3283 break;
3285 default:
3286 if (sig == SR_signum) {
3287 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3288 } else {
3289 return;
3290 }
3291 break;
3292 }
3294 if (thisHandler != jvmHandler) {
3295 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3296 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3297 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3298 // No need to check this sig any longer
3299 sigaddset(&check_signal_done, sig);
3300 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3301 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3302 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3303 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3304 // No need to check this sig any longer
3305 sigaddset(&check_signal_done, sig);
3306 }
3308 // Dump all the signal
3309 if (sigismember(&check_signal_done, sig)) {
3310 print_signal_handlers(tty, buf, O_BUFLEN);
3311 }
3312 }
3314 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3316 extern bool signal_name(int signo, char* buf, size_t len);
3318 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3319 if (0 < exception_code && exception_code <= SIGRTMAX) {
3320 // signal
3321 if (!signal_name(exception_code, buf, size)) {
3322 jio_snprintf(buf, size, "SIG%d", exception_code);
3323 }
3324 return buf;
3325 } else {
3326 return NULL;
3327 }
3328 }
3330 // this is called _before_ the most of global arguments have been parsed
3331 void os::init(void) {
3332 char dummy; /* used to get a guess on initial stack address */
3333 // first_hrtime = gethrtime();
3335 // With BsdThreads the JavaMain thread pid (primordial thread)
3336 // is different than the pid of the java launcher thread.
3337 // So, on Bsd, the launcher thread pid is passed to the VM
3338 // via the sun.java.launcher.pid property.
3339 // Use this property instead of getpid() if it was correctly passed.
3340 // See bug 6351349.
3341 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3343 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3345 clock_tics_per_sec = CLK_TCK;
3347 init_random(1234567);
3349 ThreadCritical::initialize();
3351 Bsd::set_page_size(getpagesize());
3352 if (Bsd::page_size() == -1) {
3353 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3354 strerror(errno)));
3355 }
3356 init_page_sizes((size_t) Bsd::page_size());
3358 Bsd::initialize_system_info();
3360 // main_thread points to the aboriginal thread
3361 Bsd::_main_thread = pthread_self();
3363 Bsd::clock_init();
3364 initial_time_count = os::elapsed_counter();
3366 #ifdef __APPLE__
3367 // XXXDARWIN
3368 // Work around the unaligned VM callbacks in hotspot's
3369 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3370 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3371 // alignment when doing symbol lookup. To work around this, we force early
3372 // binding of all symbols now, thus binding when alignment is known-good.
3373 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3374 #endif
3375 }
3377 // To install functions for atexit system call
3378 extern "C" {
3379 static void perfMemory_exit_helper() {
3380 perfMemory_exit();
3381 }
3382 }
3384 // this is called _after_ the global arguments have been parsed
3385 jint os::init_2(void)
3386 {
3387 // Allocate a single page and mark it as readable for safepoint polling
3388 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3389 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3391 os::set_polling_page( polling_page );
3393 #ifndef PRODUCT
3394 if(Verbose && PrintMiscellaneous)
3395 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3396 #endif
3398 if (!UseMembar) {
3399 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3400 guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3401 os::set_memory_serialize_page( mem_serialize_page );
3403 #ifndef PRODUCT
3404 if(Verbose && PrintMiscellaneous)
3405 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3406 #endif
3407 }
3409 os::large_page_init();
3411 // initialize suspend/resume support - must do this before signal_sets_init()
3412 if (SR_initialize() != 0) {
3413 perror("SR_initialize failed");
3414 return JNI_ERR;
3415 }
3417 Bsd::signal_sets_init();
3418 Bsd::install_signal_handlers();
3420 // Check minimum allowable stack size for thread creation and to initialize
3421 // the java system classes, including StackOverflowError - depends on page
3422 // size. Add a page for compiler2 recursion in main thread.
3423 // Add in 2*BytesPerWord times page size to account for VM stack during
3424 // class initialization depending on 32 or 64 bit VM.
3425 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3426 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3427 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3429 size_t threadStackSizeInBytes = ThreadStackSize * K;
3430 if (threadStackSizeInBytes != 0 &&
3431 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3432 tty->print_cr("\nThe stack size specified is too small, "
3433 "Specify at least %dk",
3434 os::Bsd::min_stack_allowed/ K);
3435 return JNI_ERR;
3436 }
3438 // Make the stack size a multiple of the page size so that
3439 // the yellow/red zones can be guarded.
3440 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3441 vm_page_size()));
3443 if (MaxFDLimit) {
3444 // set the number of file descriptors to max. print out error
3445 // if getrlimit/setrlimit fails but continue regardless.
3446 struct rlimit nbr_files;
3447 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3448 if (status != 0) {
3449 if (PrintMiscellaneous && (Verbose || WizardMode))
3450 perror("os::init_2 getrlimit failed");
3451 } else {
3452 nbr_files.rlim_cur = nbr_files.rlim_max;
3454 #ifdef __APPLE__
3455 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3456 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3457 // be used instead
3458 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3459 #endif
3461 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3462 if (status != 0) {
3463 if (PrintMiscellaneous && (Verbose || WizardMode))
3464 perror("os::init_2 setrlimit failed");
3465 }
3466 }
3467 }
3469 // at-exit methods are called in the reverse order of their registration.
3470 // atexit functions are called on return from main or as a result of a
3471 // call to exit(3C). There can be only 32 of these functions registered
3472 // and atexit() does not set errno.
3474 if (PerfAllowAtExitRegistration) {
3475 // only register atexit functions if PerfAllowAtExitRegistration is set.
3476 // atexit functions can be delayed until process exit time, which
3477 // can be problematic for embedded VM situations. Embedded VMs should
3478 // call DestroyJavaVM() to assure that VM resources are released.
3480 // note: perfMemory_exit_helper atexit function may be removed in
3481 // the future if the appropriate cleanup code can be added to the
3482 // VM_Exit VMOperation's doit method.
3483 if (atexit(perfMemory_exit_helper) != 0) {
3484 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3485 }
3486 }
3488 // initialize thread priority policy
3489 prio_init();
3491 #ifdef __APPLE__
3492 // dynamically link to objective c gc registration
3493 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3494 if (handleLibObjc != NULL) {
3495 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3496 }
3497 #endif
3499 return JNI_OK;
3500 }
3502 // this is called at the end of vm_initialization
3503 void os::init_3(void) { }
3505 // Mark the polling page as unreadable
3506 void os::make_polling_page_unreadable(void) {
3507 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3508 fatal("Could not disable polling page");
3509 };
3511 // Mark the polling page as readable
3512 void os::make_polling_page_readable(void) {
3513 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3514 fatal("Could not enable polling page");
3515 }
3516 };
3518 int os::active_processor_count() {
3519 return _processor_count;
3520 }
3522 void os::set_native_thread_name(const char *name) {
3523 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3524 // This is only supported in Snow Leopard and beyond
3525 if (name != NULL) {
3526 // Add a "Java: " prefix to the name
3527 char buf[MAXTHREADNAMESIZE];
3528 snprintf(buf, sizeof(buf), "Java: %s", name);
3529 pthread_setname_np(buf);
3530 }
3531 #endif
3532 }
3534 bool os::distribute_processes(uint length, uint* distribution) {
3535 // Not yet implemented.
3536 return false;
3537 }
3539 bool os::bind_to_processor(uint processor_id) {
3540 // Not yet implemented.
3541 return false;
3542 }
3544 ///
3546 // Suspends the target using the signal mechanism and then grabs the PC before
3547 // resuming the target. Used by the flat-profiler only
3548 ExtendedPC os::get_thread_pc(Thread* thread) {
3549 // Make sure that it is called by the watcher for the VMThread
3550 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3551 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3553 ExtendedPC epc;
3555 OSThread* osthread = thread->osthread();
3556 if (do_suspend(osthread)) {
3557 if (osthread->ucontext() != NULL) {
3558 epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
3559 } else {
3560 // NULL context is unexpected, double-check this is the VMThread
3561 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3562 }
3563 do_resume(osthread);
3564 }
3565 // failure means pthread_kill failed for some reason - arguably this is
3566 // a fatal problem, but such problems are ignored elsewhere
3568 return epc;
3569 }
3571 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3572 {
3573 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3574 }
3576 ////////////////////////////////////////////////////////////////////////////////
3577 // debug support
3579 bool os::find(address addr, outputStream* st) {
3580 Dl_info dlinfo;
3581 memset(&dlinfo, 0, sizeof(dlinfo));
3582 if (dladdr(addr, &dlinfo)) {
3583 st->print(PTR_FORMAT ": ", addr);
3584 if (dlinfo.dli_sname != NULL) {
3585 st->print("%s+%#x", dlinfo.dli_sname,
3586 addr - (intptr_t)dlinfo.dli_saddr);
3587 } else if (dlinfo.dli_fname) {
3588 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3589 } else {
3590 st->print("<absolute address>");
3591 }
3592 if (dlinfo.dli_fname) {
3593 st->print(" in %s", dlinfo.dli_fname);
3594 }
3595 if (dlinfo.dli_fbase) {
3596 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3597 }
3598 st->cr();
3600 if (Verbose) {
3601 // decode some bytes around the PC
3602 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3603 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3604 address lowest = (address) dlinfo.dli_sname;
3605 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3606 if (begin < lowest) begin = lowest;
3607 Dl_info dlinfo2;
3608 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
3609 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3610 end = (address) dlinfo2.dli_saddr;
3611 Disassembler::decode(begin, end, st);
3612 }
3613 return true;
3614 }
3615 return false;
3616 }
3618 ////////////////////////////////////////////////////////////////////////////////
3619 // misc
3621 // This does not do anything on Bsd. This is basically a hook for being
3622 // able to use structured exception handling (thread-local exception filters)
3623 // on, e.g., Win32.
3624 void
3625 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3626 JavaCallArguments* args, Thread* thread) {
3627 f(value, method, args, thread);
3628 }
3630 void os::print_statistics() {
3631 }
3633 int os::message_box(const char* title, const char* message) {
3634 int i;
3635 fdStream err(defaultStream::error_fd());
3636 for (i = 0; i < 78; i++) err.print_raw("=");
3637 err.cr();
3638 err.print_raw_cr(title);
3639 for (i = 0; i < 78; i++) err.print_raw("-");
3640 err.cr();
3641 err.print_raw_cr(message);
3642 for (i = 0; i < 78; i++) err.print_raw("=");
3643 err.cr();
3645 char buf[16];
3646 // Prevent process from exiting upon "read error" without consuming all CPU
3647 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3649 return buf[0] == 'y' || buf[0] == 'Y';
3650 }
3652 int os::stat(const char *path, struct stat *sbuf) {
3653 char pathbuf[MAX_PATH];
3654 if (strlen(path) > MAX_PATH - 1) {
3655 errno = ENAMETOOLONG;
3656 return -1;
3657 }
3658 os::native_path(strcpy(pathbuf, path));
3659 return ::stat(pathbuf, sbuf);
3660 }
3662 bool os::check_heap(bool force) {
3663 return true;
3664 }
3666 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3667 return ::vsnprintf(buf, count, format, args);
3668 }
3670 // Is a (classpath) directory empty?
3671 bool os::dir_is_empty(const char* path) {
3672 DIR *dir = NULL;
3673 struct dirent *ptr;
3675 dir = opendir(path);
3676 if (dir == NULL) return true;
3678 /* Scan the directory */
3679 bool result = true;
3680 char buf[sizeof(struct dirent) + MAX_PATH];
3681 while (result && (ptr = ::readdir(dir)) != NULL) {
3682 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3683 result = false;
3684 }
3685 }
3686 closedir(dir);
3687 return result;
3688 }
3690 // This code originates from JDK's sysOpen and open64_w
3691 // from src/solaris/hpi/src/system_md.c
3693 #ifndef O_DELETE
3694 #define O_DELETE 0x10000
3695 #endif
3697 // Open a file. Unlink the file immediately after open returns
3698 // if the specified oflag has the O_DELETE flag set.
3699 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3701 int os::open(const char *path, int oflag, int mode) {
3703 if (strlen(path) > MAX_PATH - 1) {
3704 errno = ENAMETOOLONG;
3705 return -1;
3706 }
3707 int fd;
3708 int o_delete = (oflag & O_DELETE);
3709 oflag = oflag & ~O_DELETE;
3711 fd = ::open(path, oflag, mode);
3712 if (fd == -1) return -1;
3714 //If the open succeeded, the file might still be a directory
3715 {
3716 struct stat buf;
3717 int ret = ::fstat(fd, &buf);
3718 int st_mode = buf.st_mode;
3720 if (ret != -1) {
3721 if ((st_mode & S_IFMT) == S_IFDIR) {
3722 errno = EISDIR;
3723 ::close(fd);
3724 return -1;
3725 }
3726 } else {
3727 ::close(fd);
3728 return -1;
3729 }
3730 }
3732 /*
3733 * All file descriptors that are opened in the JVM and not
3734 * specifically destined for a subprocess should have the
3735 * close-on-exec flag set. If we don't set it, then careless 3rd
3736 * party native code might fork and exec without closing all
3737 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3738 * UNIXProcess.c), and this in turn might:
3739 *
3740 * - cause end-of-file to fail to be detected on some file
3741 * descriptors, resulting in mysterious hangs, or
3742 *
3743 * - might cause an fopen in the subprocess to fail on a system
3744 * suffering from bug 1085341.
3745 *
3746 * (Yes, the default setting of the close-on-exec flag is a Unix
3747 * design flaw)
3748 *
3749 * See:
3750 * 1085341: 32-bit stdio routines should support file descriptors >255
3751 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3752 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3753 */
3754 #ifdef FD_CLOEXEC
3755 {
3756 int flags = ::fcntl(fd, F_GETFD);
3757 if (flags != -1)
3758 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3759 }
3760 #endif
3762 if (o_delete != 0) {
3763 ::unlink(path);
3764 }
3765 return fd;
3766 }
3769 // create binary file, rewriting existing file if required
3770 int os::create_binary_file(const char* path, bool rewrite_existing) {
3771 int oflags = O_WRONLY | O_CREAT;
3772 if (!rewrite_existing) {
3773 oflags |= O_EXCL;
3774 }
3775 return ::open(path, oflags, S_IREAD | S_IWRITE);
3776 }
3778 // return current position of file pointer
3779 jlong os::current_file_offset(int fd) {
3780 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3781 }
3783 // move file pointer to the specified offset
3784 jlong os::seek_to_file_offset(int fd, jlong offset) {
3785 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3786 }
3788 // This code originates from JDK's sysAvailable
3789 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3791 int os::available(int fd, jlong *bytes) {
3792 jlong cur, end;
3793 int mode;
3794 struct stat buf;
3796 if (::fstat(fd, &buf) >= 0) {
3797 mode = buf.st_mode;
3798 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3799 /*
3800 * XXX: is the following call interruptible? If so, this might
3801 * need to go through the INTERRUPT_IO() wrapper as for other
3802 * blocking, interruptible calls in this file.
3803 */
3804 int n;
3805 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3806 *bytes = n;
3807 return 1;
3808 }
3809 }
3810 }
3811 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3812 return 0;
3813 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3814 return 0;
3815 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3816 return 0;
3817 }
3818 *bytes = end - cur;
3819 return 1;
3820 }
3822 int os::socket_available(int fd, jint *pbytes) {
3823 if (fd < 0)
3824 return OS_OK;
3826 int ret;
3828 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3830 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3831 // is expected to return 0 on failure and 1 on success to the jdk.
3833 return (ret == OS_ERR) ? 0 : 1;
3834 }
3836 // Map a block of memory.
3837 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3838 char *addr, size_t bytes, bool read_only,
3839 bool allow_exec) {
3840 int prot;
3841 int flags;
3843 if (read_only) {
3844 prot = PROT_READ;
3845 flags = MAP_SHARED;
3846 } else {
3847 prot = PROT_READ | PROT_WRITE;
3848 flags = MAP_PRIVATE;
3849 }
3851 if (allow_exec) {
3852 prot |= PROT_EXEC;
3853 }
3855 if (addr != NULL) {
3856 flags |= MAP_FIXED;
3857 }
3859 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3860 fd, file_offset);
3861 if (mapped_address == MAP_FAILED) {
3862 return NULL;
3863 }
3864 return mapped_address;
3865 }
3868 // Remap a block of memory.
3869 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3870 char *addr, size_t bytes, bool read_only,
3871 bool allow_exec) {
3872 // same as map_memory() on this OS
3873 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3874 allow_exec);
3875 }
3878 // Unmap a block of memory.
3879 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3880 return munmap(addr, bytes) == 0;
3881 }
3883 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3884 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3885 // of a thread.
3886 //
3887 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3888 // the fast estimate available on the platform.
3890 jlong os::current_thread_cpu_time() {
3891 #ifdef __APPLE__
3892 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3893 #else
3894 Unimplemented();
3895 return 0;
3896 #endif
3897 }
3899 jlong os::thread_cpu_time(Thread* thread) {
3900 #ifdef __APPLE__
3901 return os::thread_cpu_time(thread, true /* user + sys */);
3902 #else
3903 Unimplemented();
3904 return 0;
3905 #endif
3906 }
3908 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3909 #ifdef __APPLE__
3910 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3911 #else
3912 Unimplemented();
3913 return 0;
3914 #endif
3915 }
3917 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3918 #ifdef __APPLE__
3919 struct thread_basic_info tinfo;
3920 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3921 kern_return_t kr;
3922 thread_t mach_thread;
3924 mach_thread = thread->osthread()->thread_id();
3925 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3926 if (kr != KERN_SUCCESS)
3927 return -1;
3929 if (user_sys_cpu_time) {
3930 jlong nanos;
3931 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3932 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3933 return nanos;
3934 } else {
3935 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3936 }
3937 #else
3938 Unimplemented();
3939 return 0;
3940 #endif
3941 }
3944 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3945 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3946 info_ptr->may_skip_backward = false; // elapsed time not wall time
3947 info_ptr->may_skip_forward = false; // elapsed time not wall time
3948 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3949 }
3951 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3952 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3953 info_ptr->may_skip_backward = false; // elapsed time not wall time
3954 info_ptr->may_skip_forward = false; // elapsed time not wall time
3955 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3956 }
3958 bool os::is_thread_cpu_time_supported() {
3959 #ifdef __APPLE__
3960 return true;
3961 #else
3962 return false;
3963 #endif
3964 }
3966 // System loadavg support. Returns -1 if load average cannot be obtained.
3967 // Bsd doesn't yet have a (official) notion of processor sets,
3968 // so just return the system wide load average.
3969 int os::loadavg(double loadavg[], int nelem) {
3970 return ::getloadavg(loadavg, nelem);
3971 }
3973 void os::pause() {
3974 char filename[MAX_PATH];
3975 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3976 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3977 } else {
3978 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3979 }
3981 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3982 if (fd != -1) {
3983 struct stat buf;
3984 ::close(fd);
3985 while (::stat(filename, &buf) == 0) {
3986 (void)::poll(NULL, 0, 100);
3987 }
3988 } else {
3989 jio_fprintf(stderr,
3990 "Could not open pause file '%s', continuing immediately.\n", filename);
3991 }
3992 }
3995 // Refer to the comments in os_solaris.cpp park-unpark.
3996 //
3997 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
3998 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
3999 // For specifics regarding the bug see GLIBC BUGID 261237 :
4000 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4001 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4002 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4003 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4004 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4005 // and monitorenter when we're using 1-0 locking. All those operations may result in
4006 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4007 // of libpthread avoids the problem, but isn't practical.
4008 //
4009 // Possible remedies:
4010 //
4011 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4012 // This is palliative and probabilistic, however. If the thread is preempted
4013 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4014 // than the minimum period may have passed, and the abstime may be stale (in the
4015 // past) resultin in a hang. Using this technique reduces the odds of a hang
4016 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4017 //
4018 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4019 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4020 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4021 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4022 // thread.
4023 //
4024 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4025 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4026 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4027 // This also works well. In fact it avoids kernel-level scalability impediments
4028 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4029 // timers in a graceful fashion.
4030 //
4031 // 4. When the abstime value is in the past it appears that control returns
4032 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4033 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4034 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4035 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4036 // It may be possible to avoid reinitialization by checking the return
4037 // value from pthread_cond_timedwait(). In addition to reinitializing the
4038 // condvar we must establish the invariant that cond_signal() is only called
4039 // within critical sections protected by the adjunct mutex. This prevents
4040 // cond_signal() from "seeing" a condvar that's in the midst of being
4041 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4042 // desirable signal-after-unlock optimization that avoids futile context switching.
4043 //
4044 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4045 // structure when a condvar is used or initialized. cond_destroy() would
4046 // release the helper structure. Our reinitialize-after-timedwait fix
4047 // put excessive stress on malloc/free and locks protecting the c-heap.
4048 //
4049 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4050 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4051 // and only enabling the work-around for vulnerable environments.
4053 // utility to compute the abstime argument to timedwait:
4054 // millis is the relative timeout time
4055 // abstime will be the absolute timeout time
4056 // TODO: replace compute_abstime() with unpackTime()
4058 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4059 if (millis < 0) millis = 0;
4060 struct timeval now;
4061 int status = gettimeofday(&now, NULL);
4062 assert(status == 0, "gettimeofday");
4063 jlong seconds = millis / 1000;
4064 millis %= 1000;
4065 if (seconds > 50000000) { // see man cond_timedwait(3T)
4066 seconds = 50000000;
4067 }
4068 abstime->tv_sec = now.tv_sec + seconds;
4069 long usec = now.tv_usec + millis * 1000;
4070 if (usec >= 1000000) {
4071 abstime->tv_sec += 1;
4072 usec -= 1000000;
4073 }
4074 abstime->tv_nsec = usec * 1000;
4075 return abstime;
4076 }
4079 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4080 // Conceptually TryPark() should be equivalent to park(0).
4082 int os::PlatformEvent::TryPark() {
4083 for (;;) {
4084 const int v = _Event ;
4085 guarantee ((v == 0) || (v == 1), "invariant") ;
4086 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4087 }
4088 }
4090 void os::PlatformEvent::park() { // AKA "down()"
4091 // Invariant: Only the thread associated with the Event/PlatformEvent
4092 // may call park().
4093 // TODO: assert that _Assoc != NULL or _Assoc == Self
4094 int v ;
4095 for (;;) {
4096 v = _Event ;
4097 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4098 }
4099 guarantee (v >= 0, "invariant") ;
4100 if (v == 0) {
4101 // Do this the hard way by blocking ...
4102 int status = pthread_mutex_lock(_mutex);
4103 assert_status(status == 0, status, "mutex_lock");
4104 guarantee (_nParked == 0, "invariant") ;
4105 ++ _nParked ;
4106 while (_Event < 0) {
4107 status = pthread_cond_wait(_cond, _mutex);
4108 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4109 // Treat this the same as if the wait was interrupted
4110 if (status == ETIMEDOUT) { status = EINTR; }
4111 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4112 }
4113 -- _nParked ;
4115 _Event = 0 ;
4116 status = pthread_mutex_unlock(_mutex);
4117 assert_status(status == 0, status, "mutex_unlock");
4118 // Paranoia to ensure our locked and lock-free paths interact
4119 // correctly with each other.
4120 OrderAccess::fence();
4121 }
4122 guarantee (_Event >= 0, "invariant") ;
4123 }
4125 int os::PlatformEvent::park(jlong millis) {
4126 guarantee (_nParked == 0, "invariant") ;
4128 int v ;
4129 for (;;) {
4130 v = _Event ;
4131 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4132 }
4133 guarantee (v >= 0, "invariant") ;
4134 if (v != 0) return OS_OK ;
4136 // We do this the hard way, by blocking the thread.
4137 // Consider enforcing a minimum timeout value.
4138 struct timespec abst;
4139 compute_abstime(&abst, millis);
4141 int ret = OS_TIMEOUT;
4142 int status = pthread_mutex_lock(_mutex);
4143 assert_status(status == 0, status, "mutex_lock");
4144 guarantee (_nParked == 0, "invariant") ;
4145 ++_nParked ;
4147 // Object.wait(timo) will return because of
4148 // (a) notification
4149 // (b) timeout
4150 // (c) thread.interrupt
4151 //
4152 // Thread.interrupt and object.notify{All} both call Event::set.
4153 // That is, we treat thread.interrupt as a special case of notification.
4154 // The underlying Solaris implementation, cond_timedwait, admits
4155 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4156 // JVM from making those visible to Java code. As such, we must
4157 // filter out spurious wakeups. We assume all ETIME returns are valid.
4158 //
4159 // TODO: properly differentiate simultaneous notify+interrupt.
4160 // In that case, we should propagate the notify to another waiter.
4162 while (_Event < 0) {
4163 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4164 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4165 pthread_cond_destroy (_cond);
4166 pthread_cond_init (_cond, NULL) ;
4167 }
4168 assert_status(status == 0 || status == EINTR ||
4169 status == ETIMEDOUT,
4170 status, "cond_timedwait");
4171 if (!FilterSpuriousWakeups) break ; // previous semantics
4172 if (status == ETIMEDOUT) break ;
4173 // We consume and ignore EINTR and spurious wakeups.
4174 }
4175 --_nParked ;
4176 if (_Event >= 0) {
4177 ret = OS_OK;
4178 }
4179 _Event = 0 ;
4180 status = pthread_mutex_unlock(_mutex);
4181 assert_status(status == 0, status, "mutex_unlock");
4182 assert (_nParked == 0, "invariant") ;
4183 // Paranoia to ensure our locked and lock-free paths interact
4184 // correctly with each other.
4185 OrderAccess::fence();
4186 return ret;
4187 }
4189 void os::PlatformEvent::unpark() {
4190 // Transitions for _Event:
4191 // 0 :=> 1
4192 // 1 :=> 1
4193 // -1 :=> either 0 or 1; must signal target thread
4194 // That is, we can safely transition _Event from -1 to either
4195 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4196 // unpark() calls.
4197 // See also: "Semaphores in Plan 9" by Mullender & Cox
4198 //
4199 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4200 // that it will take two back-to-back park() calls for the owning
4201 // thread to block. This has the benefit of forcing a spurious return
4202 // from the first park() call after an unpark() call which will help
4203 // shake out uses of park() and unpark() without condition variables.
4205 if (Atomic::xchg(1, &_Event) >= 0) return;
4207 // Wait for the thread associated with the event to vacate
4208 int status = pthread_mutex_lock(_mutex);
4209 assert_status(status == 0, status, "mutex_lock");
4210 int AnyWaiters = _nParked;
4211 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4212 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4213 AnyWaiters = 0;
4214 pthread_cond_signal(_cond);
4215 }
4216 status = pthread_mutex_unlock(_mutex);
4217 assert_status(status == 0, status, "mutex_unlock");
4218 if (AnyWaiters != 0) {
4219 status = pthread_cond_signal(_cond);
4220 assert_status(status == 0, status, "cond_signal");
4221 }
4223 // Note that we signal() _after dropping the lock for "immortal" Events.
4224 // This is safe and avoids a common class of futile wakeups. In rare
4225 // circumstances this can cause a thread to return prematurely from
4226 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4227 // simply re-test the condition and re-park itself.
4228 }
4231 // JSR166
4232 // -------------------------------------------------------
4234 /*
4235 * The solaris and bsd implementations of park/unpark are fairly
4236 * conservative for now, but can be improved. They currently use a
4237 * mutex/condvar pair, plus a a count.
4238 * Park decrements count if > 0, else does a condvar wait. Unpark
4239 * sets count to 1 and signals condvar. Only one thread ever waits
4240 * on the condvar. Contention seen when trying to park implies that someone
4241 * is unparking you, so don't wait. And spurious returns are fine, so there
4242 * is no need to track notifications.
4243 */
4245 #define MAX_SECS 100000000
4246 /*
4247 * This code is common to bsd and solaris and will be moved to a
4248 * common place in dolphin.
4249 *
4250 * The passed in time value is either a relative time in nanoseconds
4251 * or an absolute time in milliseconds. Either way it has to be unpacked
4252 * into suitable seconds and nanoseconds components and stored in the
4253 * given timespec structure.
4254 * Given time is a 64-bit value and the time_t used in the timespec is only
4255 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4256 * overflow if times way in the future are given. Further on Solaris versions
4257 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4258 * number of seconds, in abstime, is less than current_time + 100,000,000.
4259 * As it will be 28 years before "now + 100000000" will overflow we can
4260 * ignore overflow and just impose a hard-limit on seconds using the value
4261 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4262 * years from "now".
4263 */
4265 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4266 assert (time > 0, "convertTime");
4268 struct timeval now;
4269 int status = gettimeofday(&now, NULL);
4270 assert(status == 0, "gettimeofday");
4272 time_t max_secs = now.tv_sec + MAX_SECS;
4274 if (isAbsolute) {
4275 jlong secs = time / 1000;
4276 if (secs > max_secs) {
4277 absTime->tv_sec = max_secs;
4278 }
4279 else {
4280 absTime->tv_sec = secs;
4281 }
4282 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4283 }
4284 else {
4285 jlong secs = time / NANOSECS_PER_SEC;
4286 if (secs >= MAX_SECS) {
4287 absTime->tv_sec = max_secs;
4288 absTime->tv_nsec = 0;
4289 }
4290 else {
4291 absTime->tv_sec = now.tv_sec + secs;
4292 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4293 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4294 absTime->tv_nsec -= NANOSECS_PER_SEC;
4295 ++absTime->tv_sec; // note: this must be <= max_secs
4296 }
4297 }
4298 }
4299 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4300 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4301 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4302 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4303 }
4305 void Parker::park(bool isAbsolute, jlong time) {
4306 // Ideally we'd do something useful while spinning, such
4307 // as calling unpackTime().
4309 // Optional fast-path check:
4310 // Return immediately if a permit is available.
4311 // We depend on Atomic::xchg() having full barrier semantics
4312 // since we are doing a lock-free update to _counter.
4313 if (Atomic::xchg(0, &_counter) > 0) return;
4315 Thread* thread = Thread::current();
4316 assert(thread->is_Java_thread(), "Must be JavaThread");
4317 JavaThread *jt = (JavaThread *)thread;
4319 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4320 // Check interrupt before trying to wait
4321 if (Thread::is_interrupted(thread, false)) {
4322 return;
4323 }
4325 // Next, demultiplex/decode time arguments
4326 struct timespec absTime;
4327 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4328 return;
4329 }
4330 if (time > 0) {
4331 unpackTime(&absTime, isAbsolute, time);
4332 }
4335 // Enter safepoint region
4336 // Beware of deadlocks such as 6317397.
4337 // The per-thread Parker:: mutex is a classic leaf-lock.
4338 // In particular a thread must never block on the Threads_lock while
4339 // holding the Parker:: mutex. If safepoints are pending both the
4340 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4341 ThreadBlockInVM tbivm(jt);
4343 // Don't wait if cannot get lock since interference arises from
4344 // unblocking. Also. check interrupt before trying wait
4345 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4346 return;
4347 }
4349 int status ;
4350 if (_counter > 0) { // no wait needed
4351 _counter = 0;
4352 status = pthread_mutex_unlock(_mutex);
4353 assert (status == 0, "invariant") ;
4354 // Paranoia to ensure our locked and lock-free paths interact
4355 // correctly with each other and Java-level accesses.
4356 OrderAccess::fence();
4357 return;
4358 }
4360 #ifdef ASSERT
4361 // Don't catch signals while blocked; let the running threads have the signals.
4362 // (This allows a debugger to break into the running thread.)
4363 sigset_t oldsigs;
4364 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4365 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4366 #endif
4368 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4369 jt->set_suspend_equivalent();
4370 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4372 if (time == 0) {
4373 status = pthread_cond_wait (_cond, _mutex) ;
4374 } else {
4375 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4376 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4377 pthread_cond_destroy (_cond) ;
4378 pthread_cond_init (_cond, NULL);
4379 }
4380 }
4381 assert_status(status == 0 || status == EINTR ||
4382 status == ETIMEDOUT,
4383 status, "cond_timedwait");
4385 #ifdef ASSERT
4386 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4387 #endif
4389 _counter = 0 ;
4390 status = pthread_mutex_unlock(_mutex) ;
4391 assert_status(status == 0, status, "invariant") ;
4392 // Paranoia to ensure our locked and lock-free paths interact
4393 // correctly with each other and Java-level accesses.
4394 OrderAccess::fence();
4396 // If externally suspended while waiting, re-suspend
4397 if (jt->handle_special_suspend_equivalent_condition()) {
4398 jt->java_suspend_self();
4399 }
4400 }
4402 void Parker::unpark() {
4403 int s, status ;
4404 status = pthread_mutex_lock(_mutex);
4405 assert (status == 0, "invariant") ;
4406 s = _counter;
4407 _counter = 1;
4408 if (s < 1) {
4409 if (WorkAroundNPTLTimedWaitHang) {
4410 status = pthread_cond_signal (_cond) ;
4411 assert (status == 0, "invariant") ;
4412 status = pthread_mutex_unlock(_mutex);
4413 assert (status == 0, "invariant") ;
4414 } else {
4415 status = pthread_mutex_unlock(_mutex);
4416 assert (status == 0, "invariant") ;
4417 status = pthread_cond_signal (_cond) ;
4418 assert (status == 0, "invariant") ;
4419 }
4420 } else {
4421 pthread_mutex_unlock(_mutex);
4422 assert (status == 0, "invariant") ;
4423 }
4424 }
4427 /* Darwin has no "environ" in a dynamic library. */
4428 #ifdef __APPLE__
4429 #include <crt_externs.h>
4430 #define environ (*_NSGetEnviron())
4431 #else
4432 extern char** environ;
4433 #endif
4435 // Run the specified command in a separate process. Return its exit value,
4436 // or -1 on failure (e.g. can't fork a new process).
4437 // Unlike system(), this function can be called from signal handler. It
4438 // doesn't block SIGINT et al.
4439 int os::fork_and_exec(char* cmd) {
4440 const char * argv[4] = {"sh", "-c", cmd, NULL};
4442 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4443 // pthread_atfork handlers and reset pthread library. All we need is a
4444 // separate process to execve. Make a direct syscall to fork process.
4445 // On IA64 there's no fork syscall, we have to use fork() and hope for
4446 // the best...
4447 pid_t pid = fork();
4449 if (pid < 0) {
4450 // fork failed
4451 return -1;
4453 } else if (pid == 0) {
4454 // child process
4456 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4457 // first to kill every thread on the thread list. Because this list is
4458 // not reset by fork() (see notes above), execve() will instead kill
4459 // every thread in the parent process. We know this is the only thread
4460 // in the new process, so make a system call directly.
4461 // IA64 should use normal execve() from glibc to match the glibc fork()
4462 // above.
4463 execve("/bin/sh", (char* const*)argv, environ);
4465 // execve failed
4466 _exit(-1);
4468 } else {
4469 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4470 // care about the actual exit code, for now.
4472 int status;
4474 // Wait for the child process to exit. This returns immediately if
4475 // the child has already exited. */
4476 while (waitpid(pid, &status, 0) < 0) {
4477 switch (errno) {
4478 case ECHILD: return 0;
4479 case EINTR: break;
4480 default: return -1;
4481 }
4482 }
4484 if (WIFEXITED(status)) {
4485 // The child exited normally; get its exit code.
4486 return WEXITSTATUS(status);
4487 } else if (WIFSIGNALED(status)) {
4488 // The child exited because of a signal
4489 // The best value to return is 0x80 + signal number,
4490 // because that is what all Unix shells do, and because
4491 // it allows callers to distinguish between process exit and
4492 // process death by signal.
4493 return 0x80 + WTERMSIG(status);
4494 } else {
4495 // Unknown exit code; pass it through
4496 return status;
4497 }
4498 }
4499 }
4501 // is_headless_jre()
4502 //
4503 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4504 // in order to report if we are running in a headless jre
4505 //
4506 // Since JDK8 xawt/libmawt.so was moved into the same directory
4507 // as libawt.so, and renamed libawt_xawt.so
4508 //
4509 bool os::is_headless_jre() {
4510 struct stat statbuf;
4511 char buf[MAXPATHLEN];
4512 char libmawtpath[MAXPATHLEN];
4513 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4514 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4515 char *p;
4517 // Get path to libjvm.so
4518 os::jvm_path(buf, sizeof(buf));
4520 // Get rid of libjvm.so
4521 p = strrchr(buf, '/');
4522 if (p == NULL) return false;
4523 else *p = '\0';
4525 // Get rid of client or server
4526 p = strrchr(buf, '/');
4527 if (p == NULL) return false;
4528 else *p = '\0';
4530 // check xawt/libmawt.so
4531 strcpy(libmawtpath, buf);
4532 strcat(libmawtpath, xawtstr);
4533 if (::stat(libmawtpath, &statbuf) == 0) return false;
4535 // check libawt_xawt.so
4536 strcpy(libmawtpath, buf);
4537 strcat(libmawtpath, new_xawtstr);
4538 if (::stat(libmawtpath, &statbuf) == 0) return false;
4540 return true;
4541 }
4543 // Get the default path to the core file
4544 // Returns the length of the string
4545 int os::get_core_path(char* buffer, size_t bufferSize) {
4546 int n = jio_snprintf(buffer, bufferSize, "/cores");
4548 // Truncate if theoretical string was longer than bufferSize
4549 n = MIN2(n, (int)bufferSize);
4551 return n;
4552 }