Thu, 13 Jun 2013 11:16:38 -0700
8013057: assert(_needs_gc || SafepointSynchronize::is_at_safepoint()) failed: only read at safepoint
Summary: Detect mmap() commit failures in Linux and Solaris os::commit_memory() impls and call vm_exit_out_of_memory(). Add os::commit_memory_or_exit(). Also tidy up some NMT accounting and some mmap() return value checking.
Reviewed-by: zgu, stefank, dholmes, dsamersoff
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 // check if it's safe to start a new thread
630 static bool _thread_safety_check(Thread* thread) {
631 return true;
632 }
634 #ifdef __APPLE__
635 // library handle for calling objc_registerThreadWithCollector()
636 // without static linking to the libobjc library
637 #define OBJC_LIB "/usr/lib/libobjc.dylib"
638 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
639 typedef void (*objc_registerThreadWithCollector_t)();
640 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
641 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
642 #endif
644 #ifdef __APPLE__
645 static uint64_t locate_unique_thread_id() {
646 // Additional thread_id used to correlate threads in SA
647 thread_identifier_info_data_t m_ident_info;
648 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
650 thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
651 (thread_info_t) &m_ident_info, &count);
652 return m_ident_info.thread_id;
653 }
654 #endif
656 // Thread start routine for all newly created threads
657 static void *java_start(Thread *thread) {
658 // Try to randomize the cache line index of hot stack frames.
659 // This helps when threads of the same stack traces evict each other's
660 // cache lines. The threads can be either from the same JVM instance, or
661 // from different JVM instances. The benefit is especially true for
662 // processors with hyperthreading technology.
663 static int counter = 0;
664 int pid = os::current_process_id();
665 alloca(((pid ^ counter++) & 7) * 128);
667 ThreadLocalStorage::set_thread(thread);
669 OSThread* osthread = thread->osthread();
670 Monitor* sync = osthread->startThread_lock();
672 // non floating stack BsdThreads needs extra check, see above
673 if (!_thread_safety_check(thread)) {
674 // notify parent thread
675 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
676 osthread->set_state(ZOMBIE);
677 sync->notify_all();
678 return NULL;
679 }
681 #ifdef __APPLE__
682 // thread_id is mach thread on macos
683 osthread->set_thread_id(::mach_thread_self());
684 osthread->set_unique_thread_id(locate_unique_thread_id());
685 #else
686 // thread_id is pthread_id on BSD
687 osthread->set_thread_id(::pthread_self());
688 #endif
689 // initialize signal mask for this thread
690 os::Bsd::hotspot_sigmask(thread);
692 // initialize floating point control register
693 os::Bsd::init_thread_fpu_state();
695 #ifdef __APPLE__
696 // register thread with objc gc
697 if (objc_registerThreadWithCollectorFunction != NULL) {
698 objc_registerThreadWithCollectorFunction();
699 }
700 #endif
702 // handshaking with parent thread
703 {
704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
706 // notify parent thread
707 osthread->set_state(INITIALIZED);
708 sync->notify_all();
710 // wait until os::start_thread()
711 while (osthread->get_state() == INITIALIZED) {
712 sync->wait(Mutex::_no_safepoint_check_flag);
713 }
714 }
716 // call one more level start routine
717 thread->run();
719 return 0;
720 }
722 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
723 assert(thread->osthread() == NULL, "caller responsible");
725 // Allocate the OSThread object
726 OSThread* osthread = new OSThread(NULL, NULL);
727 if (osthread == NULL) {
728 return false;
729 }
731 // set the correct thread state
732 osthread->set_thread_type(thr_type);
734 // Initial state is ALLOCATED but not INITIALIZED
735 osthread->set_state(ALLOCATED);
737 thread->set_osthread(osthread);
739 // init thread attributes
740 pthread_attr_t attr;
741 pthread_attr_init(&attr);
742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
744 // stack size
745 if (os::Bsd::supports_variable_stack_size()) {
746 // calculate stack size if it's not specified by caller
747 if (stack_size == 0) {
748 stack_size = os::Bsd::default_stack_size(thr_type);
750 switch (thr_type) {
751 case os::java_thread:
752 // Java threads use ThreadStackSize which default value can be
753 // changed with the flag -Xss
754 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
755 stack_size = JavaThread::stack_size_at_create();
756 break;
757 case os::compiler_thread:
758 if (CompilerThreadStackSize > 0) {
759 stack_size = (size_t)(CompilerThreadStackSize * K);
760 break;
761 } // else fall through:
762 // use VMThreadStackSize if CompilerThreadStackSize is not defined
763 case os::vm_thread:
764 case os::pgc_thread:
765 case os::cgc_thread:
766 case os::watcher_thread:
767 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
768 break;
769 }
770 }
772 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
773 pthread_attr_setstacksize(&attr, stack_size);
774 } else {
775 // let pthread_create() pick the default value.
776 }
778 ThreadState state;
780 {
781 pthread_t tid;
782 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
784 pthread_attr_destroy(&attr);
786 if (ret != 0) {
787 if (PrintMiscellaneous && (Verbose || WizardMode)) {
788 perror("pthread_create()");
789 }
790 // Need to clean up stuff we've allocated so far
791 thread->set_osthread(NULL);
792 delete osthread;
793 return false;
794 }
796 // Store pthread info into the OSThread
797 osthread->set_pthread_id(tid);
799 // Wait until child thread is either initialized or aborted
800 {
801 Monitor* sync_with_child = osthread->startThread_lock();
802 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
803 while ((state = osthread->get_state()) == ALLOCATED) {
804 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
805 }
806 }
808 }
810 // Aborted due to thread limit being reached
811 if (state == ZOMBIE) {
812 thread->set_osthread(NULL);
813 delete osthread;
814 return false;
815 }
817 // The thread is returned suspended (in state INITIALIZED),
818 // and is started higher up in the call chain
819 assert(state == INITIALIZED, "race condition");
820 return true;
821 }
823 /////////////////////////////////////////////////////////////////////////////
824 // attach existing thread
826 // bootstrap the main thread
827 bool os::create_main_thread(JavaThread* thread) {
828 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
829 return create_attached_thread(thread);
830 }
832 bool os::create_attached_thread(JavaThread* thread) {
833 #ifdef ASSERT
834 thread->verify_not_published();
835 #endif
837 // Allocate the OSThread object
838 OSThread* osthread = new OSThread(NULL, NULL);
840 if (osthread == NULL) {
841 return false;
842 }
844 // Store pthread info into the OSThread
845 #ifdef __APPLE__
846 osthread->set_thread_id(::mach_thread_self());
847 osthread->set_unique_thread_id(locate_unique_thread_id());
848 #else
849 osthread->set_thread_id(::pthread_self());
850 #endif
851 osthread->set_pthread_id(::pthread_self());
853 // initialize floating point control register
854 os::Bsd::init_thread_fpu_state();
856 // Initial thread state is RUNNABLE
857 osthread->set_state(RUNNABLE);
859 thread->set_osthread(osthread);
861 // initialize signal mask for this thread
862 // and save the caller's signal mask
863 os::Bsd::hotspot_sigmask(thread);
865 return true;
866 }
868 void os::pd_start_thread(Thread* thread) {
869 OSThread * osthread = thread->osthread();
870 assert(osthread->get_state() != INITIALIZED, "just checking");
871 Monitor* sync_with_child = osthread->startThread_lock();
872 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
873 sync_with_child->notify();
874 }
876 // Free Bsd resources related to the OSThread
877 void os::free_thread(OSThread* osthread) {
878 assert(osthread != NULL, "osthread not set");
880 if (Thread::current()->osthread() == osthread) {
881 // Restore caller's signal mask
882 sigset_t sigmask = osthread->caller_sigmask();
883 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
884 }
886 delete osthread;
887 }
889 //////////////////////////////////////////////////////////////////////////////
890 // thread local storage
892 int os::allocate_thread_local_storage() {
893 pthread_key_t key;
894 int rslt = pthread_key_create(&key, NULL);
895 assert(rslt == 0, "cannot allocate thread local storage");
896 return (int)key;
897 }
899 // Note: This is currently not used by VM, as we don't destroy TLS key
900 // on VM exit.
901 void os::free_thread_local_storage(int index) {
902 int rslt = pthread_key_delete((pthread_key_t)index);
903 assert(rslt == 0, "invalid index");
904 }
906 void os::thread_local_storage_at_put(int index, void* value) {
907 int rslt = pthread_setspecific((pthread_key_t)index, value);
908 assert(rslt == 0, "pthread_setspecific failed");
909 }
911 extern "C" Thread* get_thread() {
912 return ThreadLocalStorage::thread();
913 }
916 ////////////////////////////////////////////////////////////////////////////////
917 // time support
919 // Time since start-up in seconds to a fine granularity.
920 // Used by VMSelfDestructTimer and the MemProfiler.
921 double os::elapsedTime() {
923 return (double)(os::elapsed_counter()) * 0.000001;
924 }
926 jlong os::elapsed_counter() {
927 timeval time;
928 int status = gettimeofday(&time, NULL);
929 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
930 }
932 jlong os::elapsed_frequency() {
933 return (1000 * 1000);
934 }
936 bool os::supports_vtime() { return true; }
937 bool os::enable_vtime() { return false; }
938 bool os::vtime_enabled() { return false; }
940 double os::elapsedVTime() {
941 // better than nothing, but not much
942 return elapsedTime();
943 }
945 jlong os::javaTimeMillis() {
946 timeval time;
947 int status = gettimeofday(&time, NULL);
948 assert(status != -1, "bsd error");
949 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
950 }
952 #ifndef CLOCK_MONOTONIC
953 #define CLOCK_MONOTONIC (1)
954 #endif
956 #ifdef __APPLE__
957 void os::Bsd::clock_init() {
958 // XXXDARWIN: Investigate replacement monotonic clock
959 }
960 #else
961 void os::Bsd::clock_init() {
962 struct timespec res;
963 struct timespec tp;
964 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
965 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
966 // yes, monotonic clock is supported
967 _clock_gettime = ::clock_gettime;
968 }
969 }
970 #endif
973 jlong os::javaTimeNanos() {
974 if (Bsd::supports_monotonic_clock()) {
975 struct timespec tp;
976 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
977 assert(status == 0, "gettime error");
978 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
979 return result;
980 } else {
981 timeval time;
982 int status = gettimeofday(&time, NULL);
983 assert(status != -1, "bsd error");
984 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
985 return 1000 * usecs;
986 }
987 }
989 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
990 if (Bsd::supports_monotonic_clock()) {
991 info_ptr->max_value = ALL_64_BITS;
993 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
994 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
995 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
996 } else {
997 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
998 info_ptr->max_value = ALL_64_BITS;
1000 // gettimeofday is a real time clock so it skips
1001 info_ptr->may_skip_backward = true;
1002 info_ptr->may_skip_forward = true;
1003 }
1005 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1006 }
1008 // Return the real, user, and system times in seconds from an
1009 // arbitrary fixed point in the past.
1010 bool os::getTimesSecs(double* process_real_time,
1011 double* process_user_time,
1012 double* process_system_time) {
1013 struct tms ticks;
1014 clock_t real_ticks = times(&ticks);
1016 if (real_ticks == (clock_t) (-1)) {
1017 return false;
1018 } else {
1019 double ticks_per_second = (double) clock_tics_per_sec;
1020 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1021 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1022 *process_real_time = ((double) real_ticks) / ticks_per_second;
1024 return true;
1025 }
1026 }
1029 char * os::local_time_string(char *buf, size_t buflen) {
1030 struct tm t;
1031 time_t long_time;
1032 time(&long_time);
1033 localtime_r(&long_time, &t);
1034 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1035 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1036 t.tm_hour, t.tm_min, t.tm_sec);
1037 return buf;
1038 }
1040 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1041 return localtime_r(clock, res);
1042 }
1044 ////////////////////////////////////////////////////////////////////////////////
1045 // runtime exit support
1047 // Note: os::shutdown() might be called very early during initialization, or
1048 // called from signal handler. Before adding something to os::shutdown(), make
1049 // sure it is async-safe and can handle partially initialized VM.
1050 void os::shutdown() {
1052 // allow PerfMemory to attempt cleanup of any persistent resources
1053 perfMemory_exit();
1055 // needs to remove object in file system
1056 AttachListener::abort();
1058 // flush buffered output, finish log files
1059 ostream_abort();
1061 // Check for abort hook
1062 abort_hook_t abort_hook = Arguments::abort_hook();
1063 if (abort_hook != NULL) {
1064 abort_hook();
1065 }
1067 }
1069 // Note: os::abort() might be called very early during initialization, or
1070 // called from signal handler. Before adding something to os::abort(), make
1071 // sure it is async-safe and can handle partially initialized VM.
1072 void os::abort(bool dump_core) {
1073 os::shutdown();
1074 if (dump_core) {
1075 #ifndef PRODUCT
1076 fdStream out(defaultStream::output_fd());
1077 out.print_raw("Current thread is ");
1078 char buf[16];
1079 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1080 out.print_raw_cr(buf);
1081 out.print_raw_cr("Dumping core ...");
1082 #endif
1083 ::abort(); // dump core
1084 }
1086 ::exit(1);
1087 }
1089 // Die immediately, no exit hook, no abort hook, no cleanup.
1090 void os::die() {
1091 // _exit() on BsdThreads only kills current thread
1092 ::abort();
1093 }
1095 // unused on bsd for now.
1096 void os::set_error_file(const char *logfile) {}
1099 // This method is a copy of JDK's sysGetLastErrorString
1100 // from src/solaris/hpi/src/system_md.c
1102 size_t os::lasterror(char *buf, size_t len) {
1104 if (errno == 0) return 0;
1106 const char *s = ::strerror(errno);
1107 size_t n = ::strlen(s);
1108 if (n >= len) {
1109 n = len - 1;
1110 }
1111 ::strncpy(buf, s, n);
1112 buf[n] = '\0';
1113 return n;
1114 }
1116 intx os::current_thread_id() {
1117 #ifdef __APPLE__
1118 return (intx)::mach_thread_self();
1119 #else
1120 return (intx)::pthread_self();
1121 #endif
1122 }
1123 int os::current_process_id() {
1125 // Under the old bsd thread library, bsd gives each thread
1126 // its own process id. Because of this each thread will return
1127 // a different pid if this method were to return the result
1128 // of getpid(2). Bsd provides no api that returns the pid
1129 // of the launcher thread for the vm. This implementation
1130 // returns a unique pid, the pid of the launcher thread
1131 // that starts the vm 'process'.
1133 // Under the NPTL, getpid() returns the same pid as the
1134 // launcher thread rather than a unique pid per thread.
1135 // Use gettid() if you want the old pre NPTL behaviour.
1137 // if you are looking for the result of a call to getpid() that
1138 // returns a unique pid for the calling thread, then look at the
1139 // OSThread::thread_id() method in osThread_bsd.hpp file
1141 return (int)(_initial_pid ? _initial_pid : getpid());
1142 }
1144 // DLL functions
1146 #define JNI_LIB_PREFIX "lib"
1147 #ifdef __APPLE__
1148 #define JNI_LIB_SUFFIX ".dylib"
1149 #else
1150 #define JNI_LIB_SUFFIX ".so"
1151 #endif
1153 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1155 // This must be hard coded because it's the system's temporary
1156 // directory not the java application's temp directory, ala java.io.tmpdir.
1157 #ifdef __APPLE__
1158 // macosx has a secure per-user temporary directory
1159 char temp_path_storage[PATH_MAX];
1160 const char* os::get_temp_directory() {
1161 static char *temp_path = NULL;
1162 if (temp_path == NULL) {
1163 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1164 if (pathSize == 0 || pathSize > PATH_MAX) {
1165 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1166 }
1167 temp_path = temp_path_storage;
1168 }
1169 return temp_path;
1170 }
1171 #else /* __APPLE__ */
1172 const char* os::get_temp_directory() { return "/tmp"; }
1173 #endif /* __APPLE__ */
1175 static bool file_exists(const char* filename) {
1176 struct stat statbuf;
1177 if (filename == NULL || strlen(filename) == 0) {
1178 return false;
1179 }
1180 return os::stat(filename, &statbuf) == 0;
1181 }
1183 bool os::dll_build_name(char* buffer, size_t buflen,
1184 const char* pname, const char* fname) {
1185 bool retval = false;
1186 // Copied from libhpi
1187 const size_t pnamelen = pname ? strlen(pname) : 0;
1189 // Return error on buffer overflow.
1190 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1191 return retval;
1192 }
1194 if (pnamelen == 0) {
1195 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1196 retval = true;
1197 } else if (strchr(pname, *os::path_separator()) != NULL) {
1198 int n;
1199 char** pelements = split_path(pname, &n);
1200 if (pelements == NULL) {
1201 return false;
1202 }
1203 for (int i = 0 ; i < n ; i++) {
1204 // Really shouldn't be NULL, but check can't hurt
1205 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1206 continue; // skip the empty path values
1207 }
1208 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1209 pelements[i], fname);
1210 if (file_exists(buffer)) {
1211 retval = true;
1212 break;
1213 }
1214 }
1215 // release the storage
1216 for (int i = 0 ; i < n ; i++) {
1217 if (pelements[i] != NULL) {
1218 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1219 }
1220 }
1221 if (pelements != NULL) {
1222 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1223 }
1224 } else {
1225 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1226 retval = true;
1227 }
1228 return retval;
1229 }
1231 // check if addr is inside libjvm.so
1232 bool os::address_is_in_vm(address addr) {
1233 static address libjvm_base_addr;
1234 Dl_info dlinfo;
1236 if (libjvm_base_addr == NULL) {
1237 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1238 libjvm_base_addr = (address)dlinfo.dli_fbase;
1239 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1240 }
1242 if (dladdr((void *)addr, &dlinfo)) {
1243 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1244 }
1246 return false;
1247 }
1250 #define MACH_MAXSYMLEN 256
1252 bool os::dll_address_to_function_name(address addr, char *buf,
1253 int buflen, int *offset) {
1254 Dl_info dlinfo;
1255 char localbuf[MACH_MAXSYMLEN];
1257 // dladdr will find names of dynamic functions only, but does
1258 // it set dli_fbase with mach_header address when it "fails" ?
1259 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1260 if (buf != NULL) {
1261 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1262 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1263 }
1264 }
1265 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1266 return true;
1267 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1268 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1269 buf, buflen, offset, dlinfo.dli_fname)) {
1270 return true;
1271 }
1272 }
1274 // Handle non-dymanic manually:
1275 if (dlinfo.dli_fbase != NULL &&
1276 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1277 if(!Decoder::demangle(localbuf, buf, buflen)) {
1278 jio_snprintf(buf, buflen, "%s", localbuf);
1279 }
1280 return true;
1281 }
1282 if (buf != NULL) buf[0] = '\0';
1283 if (offset != NULL) *offset = -1;
1284 return false;
1285 }
1287 // ported from solaris version
1288 bool os::dll_address_to_library_name(address addr, char* buf,
1289 int buflen, int* offset) {
1290 Dl_info dlinfo;
1292 if (dladdr((void*)addr, &dlinfo)){
1293 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1294 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1295 return true;
1296 } else {
1297 if (buf) buf[0] = '\0';
1298 if (offset) *offset = -1;
1299 return false;
1300 }
1301 }
1303 // Loads .dll/.so and
1304 // in case of error it checks if .dll/.so was built for the
1305 // same architecture as Hotspot is running on
1307 #ifdef __APPLE__
1308 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1309 void * result= ::dlopen(filename, RTLD_LAZY);
1310 if (result != NULL) {
1311 // Successful loading
1312 return result;
1313 }
1315 // Read system error message into ebuf
1316 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1317 ebuf[ebuflen-1]='\0';
1319 return NULL;
1320 }
1321 #else
1322 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1323 {
1324 void * result= ::dlopen(filename, RTLD_LAZY);
1325 if (result != NULL) {
1326 // Successful loading
1327 return result;
1328 }
1330 Elf32_Ehdr elf_head;
1332 // Read system error message into ebuf
1333 // It may or may not be overwritten below
1334 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1335 ebuf[ebuflen-1]='\0';
1336 int diag_msg_max_length=ebuflen-strlen(ebuf);
1337 char* diag_msg_buf=ebuf+strlen(ebuf);
1339 if (diag_msg_max_length==0) {
1340 // No more space in ebuf for additional diagnostics message
1341 return NULL;
1342 }
1345 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1347 if (file_descriptor < 0) {
1348 // Can't open library, report dlerror() message
1349 return NULL;
1350 }
1352 bool failed_to_read_elf_head=
1353 (sizeof(elf_head)!=
1354 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1356 ::close(file_descriptor);
1357 if (failed_to_read_elf_head) {
1358 // file i/o error - report dlerror() msg
1359 return NULL;
1360 }
1362 typedef struct {
1363 Elf32_Half code; // Actual value as defined in elf.h
1364 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1365 char elf_class; // 32 or 64 bit
1366 char endianess; // MSB or LSB
1367 char* name; // String representation
1368 } arch_t;
1370 #ifndef EM_486
1371 #define EM_486 6 /* Intel 80486 */
1372 #endif
1374 #ifndef EM_MIPS_RS3_LE
1375 #define EM_MIPS_RS3_LE 10 /* MIPS */
1376 #endif
1378 #ifndef EM_PPC64
1379 #define EM_PPC64 21 /* PowerPC64 */
1380 #endif
1382 #ifndef EM_S390
1383 #define EM_S390 22 /* IBM System/390 */
1384 #endif
1386 #ifndef EM_IA_64
1387 #define EM_IA_64 50 /* HP/Intel IA-64 */
1388 #endif
1390 #ifndef EM_X86_64
1391 #define EM_X86_64 62 /* AMD x86-64 */
1392 #endif
1394 static const arch_t arch_array[]={
1395 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1396 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1397 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1398 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1399 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1400 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1401 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1402 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1403 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1404 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1405 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1406 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1407 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1408 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1409 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1410 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1411 };
1413 #if (defined IA32)
1414 static Elf32_Half running_arch_code=EM_386;
1415 #elif (defined AMD64)
1416 static Elf32_Half running_arch_code=EM_X86_64;
1417 #elif (defined IA64)
1418 static Elf32_Half running_arch_code=EM_IA_64;
1419 #elif (defined __sparc) && (defined _LP64)
1420 static Elf32_Half running_arch_code=EM_SPARCV9;
1421 #elif (defined __sparc) && (!defined _LP64)
1422 static Elf32_Half running_arch_code=EM_SPARC;
1423 #elif (defined __powerpc64__)
1424 static Elf32_Half running_arch_code=EM_PPC64;
1425 #elif (defined __powerpc__)
1426 static Elf32_Half running_arch_code=EM_PPC;
1427 #elif (defined ARM)
1428 static Elf32_Half running_arch_code=EM_ARM;
1429 #elif (defined S390)
1430 static Elf32_Half running_arch_code=EM_S390;
1431 #elif (defined ALPHA)
1432 static Elf32_Half running_arch_code=EM_ALPHA;
1433 #elif (defined MIPSEL)
1434 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1435 #elif (defined PARISC)
1436 static Elf32_Half running_arch_code=EM_PARISC;
1437 #elif (defined MIPS)
1438 static Elf32_Half running_arch_code=EM_MIPS;
1439 #elif (defined M68K)
1440 static Elf32_Half running_arch_code=EM_68K;
1441 #else
1442 #error Method os::dll_load requires that one of following is defined:\
1443 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1444 #endif
1446 // Identify compatability class for VM's architecture and library's architecture
1447 // Obtain string descriptions for architectures
1449 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1450 int running_arch_index=-1;
1452 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1453 if (running_arch_code == arch_array[i].code) {
1454 running_arch_index = i;
1455 }
1456 if (lib_arch.code == arch_array[i].code) {
1457 lib_arch.compat_class = arch_array[i].compat_class;
1458 lib_arch.name = arch_array[i].name;
1459 }
1460 }
1462 assert(running_arch_index != -1,
1463 "Didn't find running architecture code (running_arch_code) in arch_array");
1464 if (running_arch_index == -1) {
1465 // Even though running architecture detection failed
1466 // we may still continue with reporting dlerror() message
1467 return NULL;
1468 }
1470 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1471 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1472 return NULL;
1473 }
1475 #ifndef S390
1476 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1477 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1478 return NULL;
1479 }
1480 #endif // !S390
1482 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1483 if ( lib_arch.name!=NULL ) {
1484 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1485 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1486 lib_arch.name, arch_array[running_arch_index].name);
1487 } else {
1488 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1489 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1490 lib_arch.code,
1491 arch_array[running_arch_index].name);
1492 }
1493 }
1495 return NULL;
1496 }
1497 #endif /* !__APPLE__ */
1499 // XXX: Do we need a lock around this as per Linux?
1500 void* os::dll_lookup(void* handle, const char* name) {
1501 return dlsym(handle, name);
1502 }
1505 static bool _print_ascii_file(const char* filename, outputStream* st) {
1506 int fd = ::open(filename, O_RDONLY);
1507 if (fd == -1) {
1508 return false;
1509 }
1511 char buf[32];
1512 int bytes;
1513 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1514 st->print_raw(buf, bytes);
1515 }
1517 ::close(fd);
1519 return true;
1520 }
1522 void os::print_dll_info(outputStream *st) {
1523 st->print_cr("Dynamic libraries:");
1524 #ifdef RTLD_DI_LINKMAP
1525 Dl_info dli;
1526 void *handle;
1527 Link_map *map;
1528 Link_map *p;
1530 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
1531 st->print_cr("Error: Cannot print dynamic libraries.");
1532 return;
1533 }
1534 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1535 if (handle == NULL) {
1536 st->print_cr("Error: Cannot print dynamic libraries.");
1537 return;
1538 }
1539 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1540 if (map == NULL) {
1541 st->print_cr("Error: Cannot print dynamic libraries.");
1542 return;
1543 }
1545 while (map->l_prev != NULL)
1546 map = map->l_prev;
1548 while (map != NULL) {
1549 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1550 map = map->l_next;
1551 }
1553 dlclose(handle);
1554 #elif defined(__APPLE__)
1555 uint32_t count;
1556 uint32_t i;
1558 count = _dyld_image_count();
1559 for (i = 1; i < count; i++) {
1560 const char *name = _dyld_get_image_name(i);
1561 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1562 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1563 }
1564 #else
1565 st->print_cr("Error: Cannot print dynamic libraries.");
1566 #endif
1567 }
1569 void os::print_os_info_brief(outputStream* st) {
1570 st->print("Bsd");
1572 os::Posix::print_uname_info(st);
1573 }
1575 void os::print_os_info(outputStream* st) {
1576 st->print("OS:");
1577 st->print("Bsd");
1579 os::Posix::print_uname_info(st);
1581 os::Posix::print_rlimit_info(st);
1583 os::Posix::print_load_average(st);
1584 }
1586 void os::pd_print_cpu_info(outputStream* st) {
1587 // Nothing to do for now.
1588 }
1590 void os::print_memory_info(outputStream* st) {
1592 st->print("Memory:");
1593 st->print(" %dk page", os::vm_page_size()>>10);
1595 st->print(", physical " UINT64_FORMAT "k",
1596 os::physical_memory() >> 10);
1597 st->print("(" UINT64_FORMAT "k free)",
1598 os::available_memory() >> 10);
1599 st->cr();
1601 // meminfo
1602 st->print("\n/proc/meminfo:\n");
1603 _print_ascii_file("/proc/meminfo", st);
1604 st->cr();
1605 }
1607 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1608 // but they're the same for all the bsd arch that we support
1609 // and they're the same for solaris but there's no common place to put this.
1610 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1611 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1612 "ILL_COPROC", "ILL_BADSTK" };
1614 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1615 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1616 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1618 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1620 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1622 void os::print_siginfo(outputStream* st, void* siginfo) {
1623 st->print("siginfo:");
1625 const int buflen = 100;
1626 char buf[buflen];
1627 siginfo_t *si = (siginfo_t*)siginfo;
1628 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1629 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1630 st->print("si_errno=%s", buf);
1631 } else {
1632 st->print("si_errno=%d", si->si_errno);
1633 }
1634 const int c = si->si_code;
1635 assert(c > 0, "unexpected si_code");
1636 switch (si->si_signo) {
1637 case SIGILL:
1638 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1639 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1640 break;
1641 case SIGFPE:
1642 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1643 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1644 break;
1645 case SIGSEGV:
1646 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1647 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1648 break;
1649 case SIGBUS:
1650 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1651 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1652 break;
1653 default:
1654 st->print(", si_code=%d", si->si_code);
1655 // no si_addr
1656 }
1658 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1659 UseSharedSpaces) {
1660 FileMapInfo* mapinfo = FileMapInfo::current_info();
1661 if (mapinfo->is_in_shared_space(si->si_addr)) {
1662 st->print("\n\nError accessing class data sharing archive." \
1663 " Mapped file inaccessible during execution, " \
1664 " possible disk/network problem.");
1665 }
1666 }
1667 st->cr();
1668 }
1671 static void print_signal_handler(outputStream* st, int sig,
1672 char* buf, size_t buflen);
1674 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1675 st->print_cr("Signal Handlers:");
1676 print_signal_handler(st, SIGSEGV, buf, buflen);
1677 print_signal_handler(st, SIGBUS , buf, buflen);
1678 print_signal_handler(st, SIGFPE , buf, buflen);
1679 print_signal_handler(st, SIGPIPE, buf, buflen);
1680 print_signal_handler(st, SIGXFSZ, buf, buflen);
1681 print_signal_handler(st, SIGILL , buf, buflen);
1682 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1683 print_signal_handler(st, SR_signum, buf, buflen);
1684 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1685 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1686 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1687 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1688 }
1690 static char saved_jvm_path[MAXPATHLEN] = {0};
1692 // Find the full path to the current module, libjvm
1693 void os::jvm_path(char *buf, jint buflen) {
1694 // Error checking.
1695 if (buflen < MAXPATHLEN) {
1696 assert(false, "must use a large-enough buffer");
1697 buf[0] = '\0';
1698 return;
1699 }
1700 // Lazy resolve the path to current module.
1701 if (saved_jvm_path[0] != 0) {
1702 strcpy(buf, saved_jvm_path);
1703 return;
1704 }
1706 char dli_fname[MAXPATHLEN];
1707 bool ret = dll_address_to_library_name(
1708 CAST_FROM_FN_PTR(address, os::jvm_path),
1709 dli_fname, sizeof(dli_fname), NULL);
1710 assert(ret != 0, "cannot locate libjvm");
1711 char *rp = realpath(dli_fname, buf);
1712 if (rp == NULL)
1713 return;
1715 if (Arguments::created_by_gamma_launcher()) {
1716 // Support for the gamma launcher. Typical value for buf is
1717 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1718 // the right place in the string, then assume we are installed in a JDK and
1719 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1720 // construct a path to the JVM being overridden.
1722 const char *p = buf + strlen(buf) - 1;
1723 for (int count = 0; p > buf && count < 5; ++count) {
1724 for (--p; p > buf && *p != '/'; --p)
1725 /* empty */ ;
1726 }
1728 if (strncmp(p, "/jre/lib/", 9) != 0) {
1729 // Look for JAVA_HOME in the environment.
1730 char* java_home_var = ::getenv("JAVA_HOME");
1731 if (java_home_var != NULL && java_home_var[0] != 0) {
1732 char* jrelib_p;
1733 int len;
1735 // Check the current module name "libjvm"
1736 p = strrchr(buf, '/');
1737 assert(strstr(p, "/libjvm") == p, "invalid library name");
1739 rp = realpath(java_home_var, buf);
1740 if (rp == NULL)
1741 return;
1743 // determine if this is a legacy image or modules image
1744 // modules image doesn't have "jre" subdirectory
1745 len = strlen(buf);
1746 jrelib_p = buf + len;
1748 // Add the appropriate library subdir
1749 snprintf(jrelib_p, buflen-len, "/jre/lib");
1750 if (0 != access(buf, F_OK)) {
1751 snprintf(jrelib_p, buflen-len, "/lib");
1752 }
1754 // Add the appropriate client or server subdir
1755 len = strlen(buf);
1756 jrelib_p = buf + len;
1757 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1758 if (0 != access(buf, F_OK)) {
1759 snprintf(jrelib_p, buflen-len, "");
1760 }
1762 // If the path exists within JAVA_HOME, add the JVM library name
1763 // to complete the path to JVM being overridden. Otherwise fallback
1764 // to the path to the current library.
1765 if (0 == access(buf, F_OK)) {
1766 // Use current module name "libjvm"
1767 len = strlen(buf);
1768 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1769 } else {
1770 // Fall back to path of current library
1771 rp = realpath(dli_fname, buf);
1772 if (rp == NULL)
1773 return;
1774 }
1775 }
1776 }
1777 }
1779 strcpy(saved_jvm_path, buf);
1780 }
1782 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1783 // no prefix required, not even "_"
1784 }
1786 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1787 // no suffix required
1788 }
1790 ////////////////////////////////////////////////////////////////////////////////
1791 // sun.misc.Signal support
1793 static volatile jint sigint_count = 0;
1795 static void
1796 UserHandler(int sig, void *siginfo, void *context) {
1797 // 4511530 - sem_post is serialized and handled by the manager thread. When
1798 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1799 // don't want to flood the manager thread with sem_post requests.
1800 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1801 return;
1803 // Ctrl-C is pressed during error reporting, likely because the error
1804 // handler fails to abort. Let VM die immediately.
1805 if (sig == SIGINT && is_error_reported()) {
1806 os::die();
1807 }
1809 os::signal_notify(sig);
1810 }
1812 void* os::user_handler() {
1813 return CAST_FROM_FN_PTR(void*, UserHandler);
1814 }
1816 extern "C" {
1817 typedef void (*sa_handler_t)(int);
1818 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1819 }
1821 void* os::signal(int signal_number, void* handler) {
1822 struct sigaction sigAct, oldSigAct;
1824 sigfillset(&(sigAct.sa_mask));
1825 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1826 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1828 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1829 // -1 means registration failed
1830 return (void *)-1;
1831 }
1833 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1834 }
1836 void os::signal_raise(int signal_number) {
1837 ::raise(signal_number);
1838 }
1840 /*
1841 * The following code is moved from os.cpp for making this
1842 * code platform specific, which it is by its very nature.
1843 */
1845 // Will be modified when max signal is changed to be dynamic
1846 int os::sigexitnum_pd() {
1847 return NSIG;
1848 }
1850 // a counter for each possible signal value
1851 static volatile jint pending_signals[NSIG+1] = { 0 };
1853 // Bsd(POSIX) specific hand shaking semaphore.
1854 #ifdef __APPLE__
1855 typedef semaphore_t os_semaphore_t;
1856 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1857 #define SEM_WAIT(sem) semaphore_wait(sem)
1858 #define SEM_POST(sem) semaphore_signal(sem)
1859 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1860 #else
1861 typedef sem_t os_semaphore_t;
1862 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1863 #define SEM_WAIT(sem) sem_wait(&sem)
1864 #define SEM_POST(sem) sem_post(&sem)
1865 #define SEM_DESTROY(sem) sem_destroy(&sem)
1866 #endif
1868 class Semaphore : public StackObj {
1869 public:
1870 Semaphore();
1871 ~Semaphore();
1872 void signal();
1873 void wait();
1874 bool trywait();
1875 bool timedwait(unsigned int sec, int nsec);
1876 private:
1877 jlong currenttime() const;
1878 semaphore_t _semaphore;
1879 };
1881 Semaphore::Semaphore() : _semaphore(0) {
1882 SEM_INIT(_semaphore, 0);
1883 }
1885 Semaphore::~Semaphore() {
1886 SEM_DESTROY(_semaphore);
1887 }
1889 void Semaphore::signal() {
1890 SEM_POST(_semaphore);
1891 }
1893 void Semaphore::wait() {
1894 SEM_WAIT(_semaphore);
1895 }
1897 jlong Semaphore::currenttime() const {
1898 struct timeval tv;
1899 gettimeofday(&tv, NULL);
1900 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1901 }
1903 #ifdef __APPLE__
1904 bool Semaphore::trywait() {
1905 return timedwait(0, 0);
1906 }
1908 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1909 kern_return_t kr = KERN_ABORTED;
1910 mach_timespec_t waitspec;
1911 waitspec.tv_sec = sec;
1912 waitspec.tv_nsec = nsec;
1914 jlong starttime = currenttime();
1916 kr = semaphore_timedwait(_semaphore, waitspec);
1917 while (kr == KERN_ABORTED) {
1918 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1920 jlong current = currenttime();
1921 jlong passedtime = current - starttime;
1923 if (passedtime >= totalwait) {
1924 waitspec.tv_sec = 0;
1925 waitspec.tv_nsec = 0;
1926 } else {
1927 jlong waittime = totalwait - (current - starttime);
1928 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1929 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1930 }
1932 kr = semaphore_timedwait(_semaphore, waitspec);
1933 }
1935 return kr == KERN_SUCCESS;
1936 }
1938 #else
1940 bool Semaphore::trywait() {
1941 return sem_trywait(&_semaphore) == 0;
1942 }
1944 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1945 struct timespec ts;
1946 jlong endtime = unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1948 while (1) {
1949 int result = sem_timedwait(&_semaphore, &ts);
1950 if (result == 0) {
1951 return true;
1952 } else if (errno == EINTR) {
1953 continue;
1954 } else if (errno == ETIMEDOUT) {
1955 return false;
1956 } else {
1957 return false;
1958 }
1959 }
1960 }
1962 #endif // __APPLE__
1964 static os_semaphore_t sig_sem;
1965 static Semaphore sr_semaphore;
1967 void os::signal_init_pd() {
1968 // Initialize signal structures
1969 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1971 // Initialize signal semaphore
1972 ::SEM_INIT(sig_sem, 0);
1973 }
1975 void os::signal_notify(int sig) {
1976 Atomic::inc(&pending_signals[sig]);
1977 ::SEM_POST(sig_sem);
1978 }
1980 static int check_pending_signals(bool wait) {
1981 Atomic::store(0, &sigint_count);
1982 for (;;) {
1983 for (int i = 0; i < NSIG + 1; i++) {
1984 jint n = pending_signals[i];
1985 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1986 return i;
1987 }
1988 }
1989 if (!wait) {
1990 return -1;
1991 }
1992 JavaThread *thread = JavaThread::current();
1993 ThreadBlockInVM tbivm(thread);
1995 bool threadIsSuspended;
1996 do {
1997 thread->set_suspend_equivalent();
1998 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1999 ::SEM_WAIT(sig_sem);
2001 // were we externally suspended while we were waiting?
2002 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2003 if (threadIsSuspended) {
2004 //
2005 // The semaphore has been incremented, but while we were waiting
2006 // another thread suspended us. We don't want to continue running
2007 // while suspended because that would surprise the thread that
2008 // suspended us.
2009 //
2010 ::SEM_POST(sig_sem);
2012 thread->java_suspend_self();
2013 }
2014 } while (threadIsSuspended);
2015 }
2016 }
2018 int os::signal_lookup() {
2019 return check_pending_signals(false);
2020 }
2022 int os::signal_wait() {
2023 return check_pending_signals(true);
2024 }
2026 ////////////////////////////////////////////////////////////////////////////////
2027 // Virtual Memory
2029 int os::vm_page_size() {
2030 // Seems redundant as all get out
2031 assert(os::Bsd::page_size() != -1, "must call os::init");
2032 return os::Bsd::page_size();
2033 }
2035 // Solaris allocates memory by pages.
2036 int os::vm_allocation_granularity() {
2037 assert(os::Bsd::page_size() != -1, "must call os::init");
2038 return os::Bsd::page_size();
2039 }
2041 // Rationale behind this function:
2042 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2043 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2044 // samples for JITted code. Here we create private executable mapping over the code cache
2045 // and then we can use standard (well, almost, as mapping can change) way to provide
2046 // info for the reporting script by storing timestamp and location of symbol
2047 void bsd_wrap_code(char* base, size_t size) {
2048 static volatile jint cnt = 0;
2050 if (!UseOprofile) {
2051 return;
2052 }
2054 char buf[PATH_MAX + 1];
2055 int num = Atomic::add(1, &cnt);
2057 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2058 os::get_temp_directory(), os::current_process_id(), num);
2059 unlink(buf);
2061 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2063 if (fd != -1) {
2064 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2065 if (rv != (off_t)-1) {
2066 if (::write(fd, "", 1) == 1) {
2067 mmap(base, size,
2068 PROT_READ|PROT_WRITE|PROT_EXEC,
2069 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2070 }
2071 }
2072 ::close(fd);
2073 unlink(buf);
2074 }
2075 }
2077 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2078 int err) {
2079 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2080 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2081 strerror(err), err);
2082 }
2084 // NOTE: Bsd kernel does not really reserve the pages for us.
2085 // All it does is to check if there are enough free pages
2086 // left at the time of mmap(). This could be a potential
2087 // problem.
2088 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2089 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2090 #ifdef __OpenBSD__
2091 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2092 if (::mprotect(addr, size, prot) == 0) {
2093 return true;
2094 }
2095 #else
2096 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2097 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2098 if (res != (uintptr_t) MAP_FAILED) {
2099 return true;
2100 }
2101 #endif
2103 // Warn about any commit errors we see in non-product builds just
2104 // in case mmap() doesn't work as described on the man page.
2105 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2107 return false;
2108 }
2110 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2111 bool exec) {
2112 // alignment_hint is ignored on this OS
2113 return pd_commit_memory(addr, size, exec);
2114 }
2116 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2117 const char* mesg) {
2118 assert(mesg != NULL, "mesg must be specified");
2119 if (!pd_commit_memory(addr, size, exec)) {
2120 // add extra info in product mode for vm_exit_out_of_memory():
2121 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2122 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2123 }
2124 }
2126 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2127 size_t alignment_hint, bool exec,
2128 const char* mesg) {
2129 // alignment_hint is ignored on this OS
2130 pd_commit_memory_or_exit(addr, size, exec, mesg);
2131 }
2133 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2134 }
2136 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2137 ::madvise(addr, bytes, MADV_DONTNEED);
2138 }
2140 void os::numa_make_global(char *addr, size_t bytes) {
2141 }
2143 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2144 }
2146 bool os::numa_topology_changed() { return false; }
2148 size_t os::numa_get_groups_num() {
2149 return 1;
2150 }
2152 int os::numa_get_group_id() {
2153 return 0;
2154 }
2156 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2157 if (size > 0) {
2158 ids[0] = 0;
2159 return 1;
2160 }
2161 return 0;
2162 }
2164 bool os::get_page_info(char *start, page_info* info) {
2165 return false;
2166 }
2168 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2169 return end;
2170 }
2173 bool os::pd_uncommit_memory(char* addr, size_t size) {
2174 #ifdef __OpenBSD__
2175 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2176 return ::mprotect(addr, size, PROT_NONE) == 0;
2177 #else
2178 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2179 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2180 return res != (uintptr_t) MAP_FAILED;
2181 #endif
2182 }
2184 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2185 return os::commit_memory(addr, size, !ExecMem);
2186 }
2188 // If this is a growable mapping, remove the guard pages entirely by
2189 // munmap()ping them. If not, just call uncommit_memory().
2190 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2191 return os::uncommit_memory(addr, size);
2192 }
2194 static address _highest_vm_reserved_address = NULL;
2196 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2197 // at 'requested_addr'. If there are existing memory mappings at the same
2198 // location, however, they will be overwritten. If 'fixed' is false,
2199 // 'requested_addr' is only treated as a hint, the return value may or
2200 // may not start from the requested address. Unlike Bsd mmap(), this
2201 // function returns NULL to indicate failure.
2202 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2203 char * addr;
2204 int flags;
2206 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2207 if (fixed) {
2208 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2209 flags |= MAP_FIXED;
2210 }
2212 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2213 // touch an uncommitted page. Otherwise, the read/write might
2214 // succeed if we have enough swap space to back the physical page.
2215 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2216 flags, -1, 0);
2218 if (addr != MAP_FAILED) {
2219 // anon_mmap() should only get called during VM initialization,
2220 // don't need lock (actually we can skip locking even it can be called
2221 // from multiple threads, because _highest_vm_reserved_address is just a
2222 // hint about the upper limit of non-stack memory regions.)
2223 if ((address)addr + bytes > _highest_vm_reserved_address) {
2224 _highest_vm_reserved_address = (address)addr + bytes;
2225 }
2226 }
2228 return addr == MAP_FAILED ? NULL : addr;
2229 }
2231 // Don't update _highest_vm_reserved_address, because there might be memory
2232 // regions above addr + size. If so, releasing a memory region only creates
2233 // a hole in the address space, it doesn't help prevent heap-stack collision.
2234 //
2235 static int anon_munmap(char * addr, size_t size) {
2236 return ::munmap(addr, size) == 0;
2237 }
2239 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2240 size_t alignment_hint) {
2241 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2242 }
2244 bool os::pd_release_memory(char* addr, size_t size) {
2245 return anon_munmap(addr, size);
2246 }
2248 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2249 // Bsd wants the mprotect address argument to be page aligned.
2250 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2252 // According to SUSv3, mprotect() should only be used with mappings
2253 // established by mmap(), and mmap() always maps whole pages. Unaligned
2254 // 'addr' likely indicates problem in the VM (e.g. trying to change
2255 // protection of malloc'ed or statically allocated memory). Check the
2256 // caller if you hit this assert.
2257 assert(addr == bottom, "sanity check");
2259 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2260 return ::mprotect(bottom, size, prot) == 0;
2261 }
2263 // Set protections specified
2264 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2265 bool is_committed) {
2266 unsigned int p = 0;
2267 switch (prot) {
2268 case MEM_PROT_NONE: p = PROT_NONE; break;
2269 case MEM_PROT_READ: p = PROT_READ; break;
2270 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2271 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2272 default:
2273 ShouldNotReachHere();
2274 }
2275 // is_committed is unused.
2276 return bsd_mprotect(addr, bytes, p);
2277 }
2279 bool os::guard_memory(char* addr, size_t size) {
2280 return bsd_mprotect(addr, size, PROT_NONE);
2281 }
2283 bool os::unguard_memory(char* addr, size_t size) {
2284 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2285 }
2287 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2288 return false;
2289 }
2291 // Large page support
2293 static size_t _large_page_size = 0;
2295 void os::large_page_init() {
2296 }
2299 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2300 // "exec" is passed in but not used. Creating the shared image for
2301 // the code cache doesn't have an SHM_X executable permission to check.
2302 assert(UseLargePages && UseSHM, "only for SHM large pages");
2304 key_t key = IPC_PRIVATE;
2305 char *addr;
2307 bool warn_on_failure = UseLargePages &&
2308 (!FLAG_IS_DEFAULT(UseLargePages) ||
2309 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2310 );
2311 char msg[128];
2313 // Create a large shared memory region to attach to based on size.
2314 // Currently, size is the total size of the heap
2315 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2316 if (shmid == -1) {
2317 // Possible reasons for shmget failure:
2318 // 1. shmmax is too small for Java heap.
2319 // > check shmmax value: cat /proc/sys/kernel/shmmax
2320 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2321 // 2. not enough large page memory.
2322 // > check available large pages: cat /proc/meminfo
2323 // > increase amount of large pages:
2324 // echo new_value > /proc/sys/vm/nr_hugepages
2325 // Note 1: different Bsd may use different name for this property,
2326 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2327 // Note 2: it's possible there's enough physical memory available but
2328 // they are so fragmented after a long run that they can't
2329 // coalesce into large pages. Try to reserve large pages when
2330 // the system is still "fresh".
2331 if (warn_on_failure) {
2332 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2333 warning(msg);
2334 }
2335 return NULL;
2336 }
2338 // attach to the region
2339 addr = (char*)shmat(shmid, req_addr, 0);
2340 int err = errno;
2342 // Remove shmid. If shmat() is successful, the actual shared memory segment
2343 // will be deleted when it's detached by shmdt() or when the process
2344 // terminates. If shmat() is not successful this will remove the shared
2345 // segment immediately.
2346 shmctl(shmid, IPC_RMID, NULL);
2348 if ((intptr_t)addr == -1) {
2349 if (warn_on_failure) {
2350 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2351 warning(msg);
2352 }
2353 return NULL;
2354 }
2356 // The memory is committed
2357 address pc = CALLER_PC;
2358 MemTracker::record_virtual_memory_reserve((address)addr, bytes, pc);
2359 MemTracker::record_virtual_memory_commit((address)addr, bytes, pc);
2361 return addr;
2362 }
2364 bool os::release_memory_special(char* base, size_t bytes) {
2365 // detaching the SHM segment will also delete it, see reserve_memory_special()
2366 int rslt = shmdt(base);
2367 if (rslt == 0) {
2368 MemTracker::record_virtual_memory_uncommit((address)base, bytes);
2369 MemTracker::record_virtual_memory_release((address)base, bytes);
2370 return true;
2371 } else {
2372 return false;
2373 }
2375 }
2377 size_t os::large_page_size() {
2378 return _large_page_size;
2379 }
2381 // HugeTLBFS allows application to commit large page memory on demand;
2382 // with SysV SHM the entire memory region must be allocated as shared
2383 // memory.
2384 bool os::can_commit_large_page_memory() {
2385 return UseHugeTLBFS;
2386 }
2388 bool os::can_execute_large_page_memory() {
2389 return UseHugeTLBFS;
2390 }
2392 // Reserve memory at an arbitrary address, only if that area is
2393 // available (and not reserved for something else).
2395 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2396 const int max_tries = 10;
2397 char* base[max_tries];
2398 size_t size[max_tries];
2399 const size_t gap = 0x000000;
2401 // Assert only that the size is a multiple of the page size, since
2402 // that's all that mmap requires, and since that's all we really know
2403 // about at this low abstraction level. If we need higher alignment,
2404 // we can either pass an alignment to this method or verify alignment
2405 // in one of the methods further up the call chain. See bug 5044738.
2406 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2408 // Repeatedly allocate blocks until the block is allocated at the
2409 // right spot. Give up after max_tries. Note that reserve_memory() will
2410 // automatically update _highest_vm_reserved_address if the call is
2411 // successful. The variable tracks the highest memory address every reserved
2412 // by JVM. It is used to detect heap-stack collision if running with
2413 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2414 // space than needed, it could confuse the collision detecting code. To
2415 // solve the problem, save current _highest_vm_reserved_address and
2416 // calculate the correct value before return.
2417 address old_highest = _highest_vm_reserved_address;
2419 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2420 // if kernel honors the hint then we can return immediately.
2421 char * addr = anon_mmap(requested_addr, bytes, false);
2422 if (addr == requested_addr) {
2423 return requested_addr;
2424 }
2426 if (addr != NULL) {
2427 // mmap() is successful but it fails to reserve at the requested address
2428 anon_munmap(addr, bytes);
2429 }
2431 int i;
2432 for (i = 0; i < max_tries; ++i) {
2433 base[i] = reserve_memory(bytes);
2435 if (base[i] != NULL) {
2436 // Is this the block we wanted?
2437 if (base[i] == requested_addr) {
2438 size[i] = bytes;
2439 break;
2440 }
2442 // Does this overlap the block we wanted? Give back the overlapped
2443 // parts and try again.
2445 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2446 if (top_overlap >= 0 && top_overlap < bytes) {
2447 unmap_memory(base[i], top_overlap);
2448 base[i] += top_overlap;
2449 size[i] = bytes - top_overlap;
2450 } else {
2451 size_t bottom_overlap = base[i] + bytes - requested_addr;
2452 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2453 unmap_memory(requested_addr, bottom_overlap);
2454 size[i] = bytes - bottom_overlap;
2455 } else {
2456 size[i] = bytes;
2457 }
2458 }
2459 }
2460 }
2462 // Give back the unused reserved pieces.
2464 for (int j = 0; j < i; ++j) {
2465 if (base[j] != NULL) {
2466 unmap_memory(base[j], size[j]);
2467 }
2468 }
2470 if (i < max_tries) {
2471 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2472 return requested_addr;
2473 } else {
2474 _highest_vm_reserved_address = old_highest;
2475 return NULL;
2476 }
2477 }
2479 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2480 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2481 }
2483 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2484 // Solaris uses poll(), bsd uses park().
2485 // Poll() is likely a better choice, assuming that Thread.interrupt()
2486 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2487 // SIGSEGV, see 4355769.
2489 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2490 assert(thread == Thread::current(), "thread consistency check");
2492 ParkEvent * const slp = thread->_SleepEvent ;
2493 slp->reset() ;
2494 OrderAccess::fence() ;
2496 if (interruptible) {
2497 jlong prevtime = javaTimeNanos();
2499 for (;;) {
2500 if (os::is_interrupted(thread, true)) {
2501 return OS_INTRPT;
2502 }
2504 jlong newtime = javaTimeNanos();
2506 if (newtime - prevtime < 0) {
2507 // time moving backwards, should only happen if no monotonic clock
2508 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2509 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2510 } else {
2511 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2512 }
2514 if(millis <= 0) {
2515 return OS_OK;
2516 }
2518 prevtime = newtime;
2520 {
2521 assert(thread->is_Java_thread(), "sanity check");
2522 JavaThread *jt = (JavaThread *) thread;
2523 ThreadBlockInVM tbivm(jt);
2524 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2526 jt->set_suspend_equivalent();
2527 // cleared by handle_special_suspend_equivalent_condition() or
2528 // java_suspend_self() via check_and_wait_while_suspended()
2530 slp->park(millis);
2532 // were we externally suspended while we were waiting?
2533 jt->check_and_wait_while_suspended();
2534 }
2535 }
2536 } else {
2537 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2538 jlong prevtime = javaTimeNanos();
2540 for (;;) {
2541 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2542 // the 1st iteration ...
2543 jlong newtime = javaTimeNanos();
2545 if (newtime - prevtime < 0) {
2546 // time moving backwards, should only happen if no monotonic clock
2547 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2548 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2549 } else {
2550 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2551 }
2553 if(millis <= 0) break ;
2555 prevtime = newtime;
2556 slp->park(millis);
2557 }
2558 return OS_OK ;
2559 }
2560 }
2562 int os::naked_sleep() {
2563 // %% make the sleep time an integer flag. for now use 1 millisec.
2564 return os::sleep(Thread::current(), 1, false);
2565 }
2567 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2568 void os::infinite_sleep() {
2569 while (true) { // sleep forever ...
2570 ::sleep(100); // ... 100 seconds at a time
2571 }
2572 }
2574 // Used to convert frequent JVM_Yield() to nops
2575 bool os::dont_yield() {
2576 return DontYieldALot;
2577 }
2579 void os::yield() {
2580 sched_yield();
2581 }
2583 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2585 void os::yield_all(int attempts) {
2586 // Yields to all threads, including threads with lower priorities
2587 // Threads on Bsd are all with same priority. The Solaris style
2588 // os::yield_all() with nanosleep(1ms) is not necessary.
2589 sched_yield();
2590 }
2592 // Called from the tight loops to possibly influence time-sharing heuristics
2593 void os::loop_breaker(int attempts) {
2594 os::yield_all(attempts);
2595 }
2597 ////////////////////////////////////////////////////////////////////////////////
2598 // thread priority support
2600 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2601 // only supports dynamic priority, static priority must be zero. For real-time
2602 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2603 // However, for large multi-threaded applications, SCHED_RR is not only slower
2604 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2605 // of 5 runs - Sep 2005).
2606 //
2607 // The following code actually changes the niceness of kernel-thread/LWP. It
2608 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2609 // not the entire user process, and user level threads are 1:1 mapped to kernel
2610 // threads. It has always been the case, but could change in the future. For
2611 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2612 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2614 #if !defined(__APPLE__)
2615 int os::java_to_os_priority[CriticalPriority + 1] = {
2616 19, // 0 Entry should never be used
2618 0, // 1 MinPriority
2619 3, // 2
2620 6, // 3
2622 10, // 4
2623 15, // 5 NormPriority
2624 18, // 6
2626 21, // 7
2627 25, // 8
2628 28, // 9 NearMaxPriority
2630 31, // 10 MaxPriority
2632 31 // 11 CriticalPriority
2633 };
2634 #else
2635 /* Using Mach high-level priority assignments */
2636 int os::java_to_os_priority[CriticalPriority + 1] = {
2637 0, // 0 Entry should never be used (MINPRI_USER)
2639 27, // 1 MinPriority
2640 28, // 2
2641 29, // 3
2643 30, // 4
2644 31, // 5 NormPriority (BASEPRI_DEFAULT)
2645 32, // 6
2647 33, // 7
2648 34, // 8
2649 35, // 9 NearMaxPriority
2651 36, // 10 MaxPriority
2653 36 // 11 CriticalPriority
2654 };
2655 #endif
2657 static int prio_init() {
2658 if (ThreadPriorityPolicy == 1) {
2659 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2660 // if effective uid is not root. Perhaps, a more elegant way of doing
2661 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2662 if (geteuid() != 0) {
2663 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2664 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2665 }
2666 ThreadPriorityPolicy = 0;
2667 }
2668 }
2669 if (UseCriticalJavaThreadPriority) {
2670 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2671 }
2672 return 0;
2673 }
2675 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2676 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2678 #ifdef __OpenBSD__
2679 // OpenBSD pthread_setprio starves low priority threads
2680 return OS_OK;
2681 #elif defined(__FreeBSD__)
2682 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2683 #elif defined(__APPLE__) || defined(__NetBSD__)
2684 struct sched_param sp;
2685 int policy;
2686 pthread_t self = pthread_self();
2688 if (pthread_getschedparam(self, &policy, &sp) != 0)
2689 return OS_ERR;
2691 sp.sched_priority = newpri;
2692 if (pthread_setschedparam(self, policy, &sp) != 0)
2693 return OS_ERR;
2695 return OS_OK;
2696 #else
2697 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2698 return (ret == 0) ? OS_OK : OS_ERR;
2699 #endif
2700 }
2702 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2703 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2704 *priority_ptr = java_to_os_priority[NormPriority];
2705 return OS_OK;
2706 }
2708 errno = 0;
2709 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2710 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2711 #elif defined(__APPLE__) || defined(__NetBSD__)
2712 int policy;
2713 struct sched_param sp;
2715 pthread_getschedparam(pthread_self(), &policy, &sp);
2716 *priority_ptr = sp.sched_priority;
2717 #else
2718 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2719 #endif
2720 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2721 }
2723 // Hint to the underlying OS that a task switch would not be good.
2724 // Void return because it's a hint and can fail.
2725 void os::hint_no_preempt() {}
2727 ////////////////////////////////////////////////////////////////////////////////
2728 // suspend/resume support
2730 // the low-level signal-based suspend/resume support is a remnant from the
2731 // old VM-suspension that used to be for java-suspension, safepoints etc,
2732 // within hotspot. Now there is a single use-case for this:
2733 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2734 // that runs in the watcher thread.
2735 // The remaining code is greatly simplified from the more general suspension
2736 // code that used to be used.
2737 //
2738 // The protocol is quite simple:
2739 // - suspend:
2740 // - sends a signal to the target thread
2741 // - polls the suspend state of the osthread using a yield loop
2742 // - target thread signal handler (SR_handler) sets suspend state
2743 // and blocks in sigsuspend until continued
2744 // - resume:
2745 // - sets target osthread state to continue
2746 // - sends signal to end the sigsuspend loop in the SR_handler
2747 //
2748 // Note that the SR_lock plays no role in this suspend/resume protocol.
2749 //
2751 static void resume_clear_context(OSThread *osthread) {
2752 osthread->set_ucontext(NULL);
2753 osthread->set_siginfo(NULL);
2754 }
2756 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2757 osthread->set_ucontext(context);
2758 osthread->set_siginfo(siginfo);
2759 }
2761 //
2762 // Handler function invoked when a thread's execution is suspended or
2763 // resumed. We have to be careful that only async-safe functions are
2764 // called here (Note: most pthread functions are not async safe and
2765 // should be avoided.)
2766 //
2767 // Note: sigwait() is a more natural fit than sigsuspend() from an
2768 // interface point of view, but sigwait() prevents the signal hander
2769 // from being run. libpthread would get very confused by not having
2770 // its signal handlers run and prevents sigwait()'s use with the
2771 // mutex granting granting signal.
2772 //
2773 // Currently only ever called on the VMThread or JavaThread
2774 //
2775 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2776 // Save and restore errno to avoid confusing native code with EINTR
2777 // after sigsuspend.
2778 int old_errno = errno;
2780 Thread* thread = Thread::current();
2781 OSThread* osthread = thread->osthread();
2782 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2784 os::SuspendResume::State current = osthread->sr.state();
2785 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2786 suspend_save_context(osthread, siginfo, context);
2788 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2789 os::SuspendResume::State state = osthread->sr.suspended();
2790 if (state == os::SuspendResume::SR_SUSPENDED) {
2791 sigset_t suspend_set; // signals for sigsuspend()
2793 // get current set of blocked signals and unblock resume signal
2794 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2795 sigdelset(&suspend_set, SR_signum);
2797 sr_semaphore.signal();
2798 // wait here until we are resumed
2799 while (1) {
2800 sigsuspend(&suspend_set);
2802 os::SuspendResume::State result = osthread->sr.running();
2803 if (result == os::SuspendResume::SR_RUNNING) {
2804 sr_semaphore.signal();
2805 break;
2806 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2807 ShouldNotReachHere();
2808 }
2809 }
2811 } else if (state == os::SuspendResume::SR_RUNNING) {
2812 // request was cancelled, continue
2813 } else {
2814 ShouldNotReachHere();
2815 }
2817 resume_clear_context(osthread);
2818 } else if (current == os::SuspendResume::SR_RUNNING) {
2819 // request was cancelled, continue
2820 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2821 // ignore
2822 } else {
2823 // ignore
2824 }
2826 errno = old_errno;
2827 }
2830 static int SR_initialize() {
2831 struct sigaction act;
2832 char *s;
2833 /* Get signal number to use for suspend/resume */
2834 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2835 int sig = ::strtol(s, 0, 10);
2836 if (sig > 0 || sig < NSIG) {
2837 SR_signum = sig;
2838 }
2839 }
2841 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2842 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2844 sigemptyset(&SR_sigset);
2845 sigaddset(&SR_sigset, SR_signum);
2847 /* Set up signal handler for suspend/resume */
2848 act.sa_flags = SA_RESTART|SA_SIGINFO;
2849 act.sa_handler = (void (*)(int)) SR_handler;
2851 // SR_signum is blocked by default.
2852 // 4528190 - We also need to block pthread restart signal (32 on all
2853 // supported Bsd platforms). Note that BsdThreads need to block
2854 // this signal for all threads to work properly. So we don't have
2855 // to use hard-coded signal number when setting up the mask.
2856 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2858 if (sigaction(SR_signum, &act, 0) == -1) {
2859 return -1;
2860 }
2862 // Save signal flag
2863 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2864 return 0;
2865 }
2867 static int sr_notify(OSThread* osthread) {
2868 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2869 assert_status(status == 0, status, "pthread_kill");
2870 return status;
2871 }
2873 // "Randomly" selected value for how long we want to spin
2874 // before bailing out on suspending a thread, also how often
2875 // we send a signal to a thread we want to resume
2876 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2877 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2879 // returns true on success and false on error - really an error is fatal
2880 // but this seems the normal response to library errors
2881 static bool do_suspend(OSThread* osthread) {
2882 assert(osthread->sr.is_running(), "thread should be running");
2883 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2885 // mark as suspended and send signal
2886 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2887 // failed to switch, state wasn't running?
2888 ShouldNotReachHere();
2889 return false;
2890 }
2892 if (sr_notify(osthread) != 0) {
2893 ShouldNotReachHere();
2894 }
2896 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2897 while (true) {
2898 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2899 break;
2900 } else {
2901 // timeout
2902 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2903 if (cancelled == os::SuspendResume::SR_RUNNING) {
2904 return false;
2905 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2906 // make sure that we consume the signal on the semaphore as well
2907 sr_semaphore.wait();
2908 break;
2909 } else {
2910 ShouldNotReachHere();
2911 return false;
2912 }
2913 }
2914 }
2916 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2917 return true;
2918 }
2920 static void do_resume(OSThread* osthread) {
2921 assert(osthread->sr.is_suspended(), "thread should be suspended");
2922 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2924 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2925 // failed to switch to WAKEUP_REQUEST
2926 ShouldNotReachHere();
2927 return;
2928 }
2930 while (true) {
2931 if (sr_notify(osthread) == 0) {
2932 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2933 if (osthread->sr.is_running()) {
2934 return;
2935 }
2936 }
2937 } else {
2938 ShouldNotReachHere();
2939 }
2940 }
2942 guarantee(osthread->sr.is_running(), "Must be running!");
2943 }
2945 ////////////////////////////////////////////////////////////////////////////////
2946 // interrupt support
2948 void os::interrupt(Thread* thread) {
2949 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2950 "possibility of dangling Thread pointer");
2952 OSThread* osthread = thread->osthread();
2954 if (!osthread->interrupted()) {
2955 osthread->set_interrupted(true);
2956 // More than one thread can get here with the same value of osthread,
2957 // resulting in multiple notifications. We do, however, want the store
2958 // to interrupted() to be visible to other threads before we execute unpark().
2959 OrderAccess::fence();
2960 ParkEvent * const slp = thread->_SleepEvent ;
2961 if (slp != NULL) slp->unpark() ;
2962 }
2964 // For JSR166. Unpark even if interrupt status already was set
2965 if (thread->is_Java_thread())
2966 ((JavaThread*)thread)->parker()->unpark();
2968 ParkEvent * ev = thread->_ParkEvent ;
2969 if (ev != NULL) ev->unpark() ;
2971 }
2973 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2974 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2975 "possibility of dangling Thread pointer");
2977 OSThread* osthread = thread->osthread();
2979 bool interrupted = osthread->interrupted();
2981 if (interrupted && clear_interrupted) {
2982 osthread->set_interrupted(false);
2983 // consider thread->_SleepEvent->reset() ... optional optimization
2984 }
2986 return interrupted;
2987 }
2989 ///////////////////////////////////////////////////////////////////////////////////
2990 // signal handling (except suspend/resume)
2992 // This routine may be used by user applications as a "hook" to catch signals.
2993 // The user-defined signal handler must pass unrecognized signals to this
2994 // routine, and if it returns true (non-zero), then the signal handler must
2995 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2996 // routine will never retun false (zero), but instead will execute a VM panic
2997 // routine kill the process.
2998 //
2999 // If this routine returns false, it is OK to call it again. This allows
3000 // the user-defined signal handler to perform checks either before or after
3001 // the VM performs its own checks. Naturally, the user code would be making
3002 // a serious error if it tried to handle an exception (such as a null check
3003 // or breakpoint) that the VM was generating for its own correct operation.
3004 //
3005 // This routine may recognize any of the following kinds of signals:
3006 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3007 // It should be consulted by handlers for any of those signals.
3008 //
3009 // The caller of this routine must pass in the three arguments supplied
3010 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3011 // field of the structure passed to sigaction(). This routine assumes that
3012 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3013 //
3014 // Note that the VM will print warnings if it detects conflicting signal
3015 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3016 //
3017 extern "C" JNIEXPORT int
3018 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3019 void* ucontext, int abort_if_unrecognized);
3021 void signalHandler(int sig, siginfo_t* info, void* uc) {
3022 assert(info != NULL && uc != NULL, "it must be old kernel");
3023 int orig_errno = errno; // Preserve errno value over signal handler.
3024 JVM_handle_bsd_signal(sig, info, uc, true);
3025 errno = orig_errno;
3026 }
3029 // This boolean allows users to forward their own non-matching signals
3030 // to JVM_handle_bsd_signal, harmlessly.
3031 bool os::Bsd::signal_handlers_are_installed = false;
3033 // For signal-chaining
3034 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3035 unsigned int os::Bsd::sigs = 0;
3036 bool os::Bsd::libjsig_is_loaded = false;
3037 typedef struct sigaction *(*get_signal_t)(int);
3038 get_signal_t os::Bsd::get_signal_action = NULL;
3040 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3041 struct sigaction *actp = NULL;
3043 if (libjsig_is_loaded) {
3044 // Retrieve the old signal handler from libjsig
3045 actp = (*get_signal_action)(sig);
3046 }
3047 if (actp == NULL) {
3048 // Retrieve the preinstalled signal handler from jvm
3049 actp = get_preinstalled_handler(sig);
3050 }
3052 return actp;
3053 }
3055 static bool call_chained_handler(struct sigaction *actp, int sig,
3056 siginfo_t *siginfo, void *context) {
3057 // Call the old signal handler
3058 if (actp->sa_handler == SIG_DFL) {
3059 // It's more reasonable to let jvm treat it as an unexpected exception
3060 // instead of taking the default action.
3061 return false;
3062 } else if (actp->sa_handler != SIG_IGN) {
3063 if ((actp->sa_flags & SA_NODEFER) == 0) {
3064 // automaticlly block the signal
3065 sigaddset(&(actp->sa_mask), sig);
3066 }
3068 sa_handler_t hand;
3069 sa_sigaction_t sa;
3070 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3071 // retrieve the chained handler
3072 if (siginfo_flag_set) {
3073 sa = actp->sa_sigaction;
3074 } else {
3075 hand = actp->sa_handler;
3076 }
3078 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3079 actp->sa_handler = SIG_DFL;
3080 }
3082 // try to honor the signal mask
3083 sigset_t oset;
3084 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3086 // call into the chained handler
3087 if (siginfo_flag_set) {
3088 (*sa)(sig, siginfo, context);
3089 } else {
3090 (*hand)(sig);
3091 }
3093 // restore the signal mask
3094 pthread_sigmask(SIG_SETMASK, &oset, 0);
3095 }
3096 // Tell jvm's signal handler the signal is taken care of.
3097 return true;
3098 }
3100 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3101 bool chained = false;
3102 // signal-chaining
3103 if (UseSignalChaining) {
3104 struct sigaction *actp = get_chained_signal_action(sig);
3105 if (actp != NULL) {
3106 chained = call_chained_handler(actp, sig, siginfo, context);
3107 }
3108 }
3109 return chained;
3110 }
3112 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3113 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3114 return &sigact[sig];
3115 }
3116 return NULL;
3117 }
3119 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3120 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3121 sigact[sig] = oldAct;
3122 sigs |= (unsigned int)1 << sig;
3123 }
3125 // for diagnostic
3126 int os::Bsd::sigflags[MAXSIGNUM];
3128 int os::Bsd::get_our_sigflags(int sig) {
3129 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3130 return sigflags[sig];
3131 }
3133 void os::Bsd::set_our_sigflags(int sig, int flags) {
3134 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3135 sigflags[sig] = flags;
3136 }
3138 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3139 // Check for overwrite.
3140 struct sigaction oldAct;
3141 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3143 void* oldhand = oldAct.sa_sigaction
3144 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3145 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3146 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3147 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3148 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3149 if (AllowUserSignalHandlers || !set_installed) {
3150 // Do not overwrite; user takes responsibility to forward to us.
3151 return;
3152 } else if (UseSignalChaining) {
3153 // save the old handler in jvm
3154 save_preinstalled_handler(sig, oldAct);
3155 // libjsig also interposes the sigaction() call below and saves the
3156 // old sigaction on it own.
3157 } else {
3158 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3159 "%#lx for signal %d.", (long)oldhand, sig));
3160 }
3161 }
3163 struct sigaction sigAct;
3164 sigfillset(&(sigAct.sa_mask));
3165 sigAct.sa_handler = SIG_DFL;
3166 if (!set_installed) {
3167 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3168 } else {
3169 sigAct.sa_sigaction = signalHandler;
3170 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3171 }
3172 #if __APPLE__
3173 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3174 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3175 // if the signal handler declares it will handle it on alternate stack.
3176 // Notice we only declare we will handle it on alt stack, but we are not
3177 // actually going to use real alt stack - this is just a workaround.
3178 // Please see ux_exception.c, method catch_mach_exception_raise for details
3179 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3180 if (sig == SIGSEGV) {
3181 sigAct.sa_flags |= SA_ONSTACK;
3182 }
3183 #endif
3185 // Save flags, which are set by ours
3186 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3187 sigflags[sig] = sigAct.sa_flags;
3189 int ret = sigaction(sig, &sigAct, &oldAct);
3190 assert(ret == 0, "check");
3192 void* oldhand2 = oldAct.sa_sigaction
3193 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3194 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3195 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3196 }
3198 // install signal handlers for signals that HotSpot needs to
3199 // handle in order to support Java-level exception handling.
3201 void os::Bsd::install_signal_handlers() {
3202 if (!signal_handlers_are_installed) {
3203 signal_handlers_are_installed = true;
3205 // signal-chaining
3206 typedef void (*signal_setting_t)();
3207 signal_setting_t begin_signal_setting = NULL;
3208 signal_setting_t end_signal_setting = NULL;
3209 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3210 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3211 if (begin_signal_setting != NULL) {
3212 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3213 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3214 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3215 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3216 libjsig_is_loaded = true;
3217 assert(UseSignalChaining, "should enable signal-chaining");
3218 }
3219 if (libjsig_is_loaded) {
3220 // Tell libjsig jvm is setting signal handlers
3221 (*begin_signal_setting)();
3222 }
3224 set_signal_handler(SIGSEGV, true);
3225 set_signal_handler(SIGPIPE, true);
3226 set_signal_handler(SIGBUS, true);
3227 set_signal_handler(SIGILL, true);
3228 set_signal_handler(SIGFPE, true);
3229 set_signal_handler(SIGXFSZ, true);
3231 #if defined(__APPLE__)
3232 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3233 // signals caught and handled by the JVM. To work around this, we reset the mach task
3234 // signal handler that's placed on our process by CrashReporter. This disables
3235 // CrashReporter-based reporting.
3236 //
3237 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3238 // on caught fatal signals.
3239 //
3240 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3241 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3242 // exception handling, while leaving the standard BSD signal handlers functional.
3243 kern_return_t kr;
3244 kr = task_set_exception_ports(mach_task_self(),
3245 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3246 MACH_PORT_NULL,
3247 EXCEPTION_STATE_IDENTITY,
3248 MACHINE_THREAD_STATE);
3250 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3251 #endif
3253 if (libjsig_is_loaded) {
3254 // Tell libjsig jvm finishes setting signal handlers
3255 (*end_signal_setting)();
3256 }
3258 // We don't activate signal checker if libjsig is in place, we trust ourselves
3259 // and if UserSignalHandler is installed all bets are off
3260 if (CheckJNICalls) {
3261 if (libjsig_is_loaded) {
3262 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3263 check_signals = false;
3264 }
3265 if (AllowUserSignalHandlers) {
3266 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3267 check_signals = false;
3268 }
3269 }
3270 }
3271 }
3274 /////
3275 // glibc on Bsd platform uses non-documented flag
3276 // to indicate, that some special sort of signal
3277 // trampoline is used.
3278 // We will never set this flag, and we should
3279 // ignore this flag in our diagnostic
3280 #ifdef SIGNIFICANT_SIGNAL_MASK
3281 #undef SIGNIFICANT_SIGNAL_MASK
3282 #endif
3283 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3285 static const char* get_signal_handler_name(address handler,
3286 char* buf, int buflen) {
3287 int offset;
3288 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3289 if (found) {
3290 // skip directory names
3291 const char *p1, *p2;
3292 p1 = buf;
3293 size_t len = strlen(os::file_separator());
3294 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3295 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3296 } else {
3297 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3298 }
3299 return buf;
3300 }
3302 static void print_signal_handler(outputStream* st, int sig,
3303 char* buf, size_t buflen) {
3304 struct sigaction sa;
3306 sigaction(sig, NULL, &sa);
3308 // See comment for SIGNIFICANT_SIGNAL_MASK define
3309 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3311 st->print("%s: ", os::exception_name(sig, buf, buflen));
3313 address handler = (sa.sa_flags & SA_SIGINFO)
3314 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3315 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3317 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3318 st->print("SIG_DFL");
3319 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3320 st->print("SIG_IGN");
3321 } else {
3322 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3323 }
3325 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3327 address rh = VMError::get_resetted_sighandler(sig);
3328 // May be, handler was resetted by VMError?
3329 if(rh != NULL) {
3330 handler = rh;
3331 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3332 }
3334 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3336 // Check: is it our handler?
3337 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3338 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3339 // It is our signal handler
3340 // check for flags, reset system-used one!
3341 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3342 st->print(
3343 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3344 os::Bsd::get_our_sigflags(sig));
3345 }
3346 }
3347 st->cr();
3348 }
3351 #define DO_SIGNAL_CHECK(sig) \
3352 if (!sigismember(&check_signal_done, sig)) \
3353 os::Bsd::check_signal_handler(sig)
3355 // This method is a periodic task to check for misbehaving JNI applications
3356 // under CheckJNI, we can add any periodic checks here
3358 void os::run_periodic_checks() {
3360 if (check_signals == false) return;
3362 // SEGV and BUS if overridden could potentially prevent
3363 // generation of hs*.log in the event of a crash, debugging
3364 // such a case can be very challenging, so we absolutely
3365 // check the following for a good measure:
3366 DO_SIGNAL_CHECK(SIGSEGV);
3367 DO_SIGNAL_CHECK(SIGILL);
3368 DO_SIGNAL_CHECK(SIGFPE);
3369 DO_SIGNAL_CHECK(SIGBUS);
3370 DO_SIGNAL_CHECK(SIGPIPE);
3371 DO_SIGNAL_CHECK(SIGXFSZ);
3374 // ReduceSignalUsage allows the user to override these handlers
3375 // see comments at the very top and jvm_solaris.h
3376 if (!ReduceSignalUsage) {
3377 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3378 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3379 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3380 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3381 }
3383 DO_SIGNAL_CHECK(SR_signum);
3384 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3385 }
3387 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3389 static os_sigaction_t os_sigaction = NULL;
3391 void os::Bsd::check_signal_handler(int sig) {
3392 char buf[O_BUFLEN];
3393 address jvmHandler = NULL;
3396 struct sigaction act;
3397 if (os_sigaction == NULL) {
3398 // only trust the default sigaction, in case it has been interposed
3399 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3400 if (os_sigaction == NULL) return;
3401 }
3403 os_sigaction(sig, (struct sigaction*)NULL, &act);
3406 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3408 address thisHandler = (act.sa_flags & SA_SIGINFO)
3409 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3410 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3413 switch(sig) {
3414 case SIGSEGV:
3415 case SIGBUS:
3416 case SIGFPE:
3417 case SIGPIPE:
3418 case SIGILL:
3419 case SIGXFSZ:
3420 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3421 break;
3423 case SHUTDOWN1_SIGNAL:
3424 case SHUTDOWN2_SIGNAL:
3425 case SHUTDOWN3_SIGNAL:
3426 case BREAK_SIGNAL:
3427 jvmHandler = (address)user_handler();
3428 break;
3430 case INTERRUPT_SIGNAL:
3431 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3432 break;
3434 default:
3435 if (sig == SR_signum) {
3436 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3437 } else {
3438 return;
3439 }
3440 break;
3441 }
3443 if (thisHandler != jvmHandler) {
3444 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3445 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3446 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3447 // No need to check this sig any longer
3448 sigaddset(&check_signal_done, sig);
3449 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3450 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3451 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3452 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3453 // No need to check this sig any longer
3454 sigaddset(&check_signal_done, sig);
3455 }
3457 // Dump all the signal
3458 if (sigismember(&check_signal_done, sig)) {
3459 print_signal_handlers(tty, buf, O_BUFLEN);
3460 }
3461 }
3463 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3465 extern bool signal_name(int signo, char* buf, size_t len);
3467 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3468 if (0 < exception_code && exception_code <= SIGRTMAX) {
3469 // signal
3470 if (!signal_name(exception_code, buf, size)) {
3471 jio_snprintf(buf, size, "SIG%d", exception_code);
3472 }
3473 return buf;
3474 } else {
3475 return NULL;
3476 }
3477 }
3479 // this is called _before_ the most of global arguments have been parsed
3480 void os::init(void) {
3481 char dummy; /* used to get a guess on initial stack address */
3482 // first_hrtime = gethrtime();
3484 // With BsdThreads the JavaMain thread pid (primordial thread)
3485 // is different than the pid of the java launcher thread.
3486 // So, on Bsd, the launcher thread pid is passed to the VM
3487 // via the sun.java.launcher.pid property.
3488 // Use this property instead of getpid() if it was correctly passed.
3489 // See bug 6351349.
3490 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3492 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3494 clock_tics_per_sec = CLK_TCK;
3496 init_random(1234567);
3498 ThreadCritical::initialize();
3500 Bsd::set_page_size(getpagesize());
3501 if (Bsd::page_size() == -1) {
3502 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3503 strerror(errno)));
3504 }
3505 init_page_sizes((size_t) Bsd::page_size());
3507 Bsd::initialize_system_info();
3509 // main_thread points to the aboriginal thread
3510 Bsd::_main_thread = pthread_self();
3512 Bsd::clock_init();
3513 initial_time_count = os::elapsed_counter();
3515 #ifdef __APPLE__
3516 // XXXDARWIN
3517 // Work around the unaligned VM callbacks in hotspot's
3518 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3519 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3520 // alignment when doing symbol lookup. To work around this, we force early
3521 // binding of all symbols now, thus binding when alignment is known-good.
3522 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3523 #endif
3524 }
3526 // To install functions for atexit system call
3527 extern "C" {
3528 static void perfMemory_exit_helper() {
3529 perfMemory_exit();
3530 }
3531 }
3533 // this is called _after_ the global arguments have been parsed
3534 jint os::init_2(void)
3535 {
3536 // Allocate a single page and mark it as readable for safepoint polling
3537 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3538 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3540 os::set_polling_page( polling_page );
3542 #ifndef PRODUCT
3543 if(Verbose && PrintMiscellaneous)
3544 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3545 #endif
3547 if (!UseMembar) {
3548 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3549 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3550 os::set_memory_serialize_page( mem_serialize_page );
3552 #ifndef PRODUCT
3553 if(Verbose && PrintMiscellaneous)
3554 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3555 #endif
3556 }
3558 os::large_page_init();
3560 // initialize suspend/resume support - must do this before signal_sets_init()
3561 if (SR_initialize() != 0) {
3562 perror("SR_initialize failed");
3563 return JNI_ERR;
3564 }
3566 Bsd::signal_sets_init();
3567 Bsd::install_signal_handlers();
3569 // Check minimum allowable stack size for thread creation and to initialize
3570 // the java system classes, including StackOverflowError - depends on page
3571 // size. Add a page for compiler2 recursion in main thread.
3572 // Add in 2*BytesPerWord times page size to account for VM stack during
3573 // class initialization depending on 32 or 64 bit VM.
3574 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3575 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3576 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3578 size_t threadStackSizeInBytes = ThreadStackSize * K;
3579 if (threadStackSizeInBytes != 0 &&
3580 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3581 tty->print_cr("\nThe stack size specified is too small, "
3582 "Specify at least %dk",
3583 os::Bsd::min_stack_allowed/ K);
3584 return JNI_ERR;
3585 }
3587 // Make the stack size a multiple of the page size so that
3588 // the yellow/red zones can be guarded.
3589 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3590 vm_page_size()));
3592 if (MaxFDLimit) {
3593 // set the number of file descriptors to max. print out error
3594 // if getrlimit/setrlimit fails but continue regardless.
3595 struct rlimit nbr_files;
3596 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3597 if (status != 0) {
3598 if (PrintMiscellaneous && (Verbose || WizardMode))
3599 perror("os::init_2 getrlimit failed");
3600 } else {
3601 nbr_files.rlim_cur = nbr_files.rlim_max;
3603 #ifdef __APPLE__
3604 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3605 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3606 // be used instead
3607 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3608 #endif
3610 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3611 if (status != 0) {
3612 if (PrintMiscellaneous && (Verbose || WizardMode))
3613 perror("os::init_2 setrlimit failed");
3614 }
3615 }
3616 }
3618 // at-exit methods are called in the reverse order of their registration.
3619 // atexit functions are called on return from main or as a result of a
3620 // call to exit(3C). There can be only 32 of these functions registered
3621 // and atexit() does not set errno.
3623 if (PerfAllowAtExitRegistration) {
3624 // only register atexit functions if PerfAllowAtExitRegistration is set.
3625 // atexit functions can be delayed until process exit time, which
3626 // can be problematic for embedded VM situations. Embedded VMs should
3627 // call DestroyJavaVM() to assure that VM resources are released.
3629 // note: perfMemory_exit_helper atexit function may be removed in
3630 // the future if the appropriate cleanup code can be added to the
3631 // VM_Exit VMOperation's doit method.
3632 if (atexit(perfMemory_exit_helper) != 0) {
3633 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3634 }
3635 }
3637 // initialize thread priority policy
3638 prio_init();
3640 #ifdef __APPLE__
3641 // dynamically link to objective c gc registration
3642 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3643 if (handleLibObjc != NULL) {
3644 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3645 }
3646 #endif
3648 return JNI_OK;
3649 }
3651 // this is called at the end of vm_initialization
3652 void os::init_3(void) { }
3654 // Mark the polling page as unreadable
3655 void os::make_polling_page_unreadable(void) {
3656 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3657 fatal("Could not disable polling page");
3658 };
3660 // Mark the polling page as readable
3661 void os::make_polling_page_readable(void) {
3662 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3663 fatal("Could not enable polling page");
3664 }
3665 };
3667 int os::active_processor_count() {
3668 return _processor_count;
3669 }
3671 void os::set_native_thread_name(const char *name) {
3672 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3673 // This is only supported in Snow Leopard and beyond
3674 if (name != NULL) {
3675 // Add a "Java: " prefix to the name
3676 char buf[MAXTHREADNAMESIZE];
3677 snprintf(buf, sizeof(buf), "Java: %s", name);
3678 pthread_setname_np(buf);
3679 }
3680 #endif
3681 }
3683 bool os::distribute_processes(uint length, uint* distribution) {
3684 // Not yet implemented.
3685 return false;
3686 }
3688 bool os::bind_to_processor(uint processor_id) {
3689 // Not yet implemented.
3690 return false;
3691 }
3693 void os::SuspendedThreadTask::internal_do_task() {
3694 if (do_suspend(_thread->osthread())) {
3695 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3696 do_task(context);
3697 do_resume(_thread->osthread());
3698 }
3699 }
3701 ///
3702 class PcFetcher : public os::SuspendedThreadTask {
3703 public:
3704 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3705 ExtendedPC result();
3706 protected:
3707 void do_task(const os::SuspendedThreadTaskContext& context);
3708 private:
3709 ExtendedPC _epc;
3710 };
3712 ExtendedPC PcFetcher::result() {
3713 guarantee(is_done(), "task is not done yet.");
3714 return _epc;
3715 }
3717 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3718 Thread* thread = context.thread();
3719 OSThread* osthread = thread->osthread();
3720 if (osthread->ucontext() != NULL) {
3721 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3722 } else {
3723 // NULL context is unexpected, double-check this is the VMThread
3724 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3725 }
3726 }
3728 // Suspends the target using the signal mechanism and then grabs the PC before
3729 // resuming the target. Used by the flat-profiler only
3730 ExtendedPC os::get_thread_pc(Thread* thread) {
3731 // Make sure that it is called by the watcher for the VMThread
3732 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3733 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3735 PcFetcher fetcher(thread);
3736 fetcher.run();
3737 return fetcher.result();
3738 }
3740 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3741 {
3742 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3743 }
3745 ////////////////////////////////////////////////////////////////////////////////
3746 // debug support
3748 bool os::find(address addr, outputStream* st) {
3749 Dl_info dlinfo;
3750 memset(&dlinfo, 0, sizeof(dlinfo));
3751 if (dladdr(addr, &dlinfo)) {
3752 st->print(PTR_FORMAT ": ", addr);
3753 if (dlinfo.dli_sname != NULL) {
3754 st->print("%s+%#x", dlinfo.dli_sname,
3755 addr - (intptr_t)dlinfo.dli_saddr);
3756 } else if (dlinfo.dli_fname) {
3757 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3758 } else {
3759 st->print("<absolute address>");
3760 }
3761 if (dlinfo.dli_fname) {
3762 st->print(" in %s", dlinfo.dli_fname);
3763 }
3764 if (dlinfo.dli_fbase) {
3765 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3766 }
3767 st->cr();
3769 if (Verbose) {
3770 // decode some bytes around the PC
3771 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3772 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3773 address lowest = (address) dlinfo.dli_sname;
3774 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3775 if (begin < lowest) begin = lowest;
3776 Dl_info dlinfo2;
3777 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
3778 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3779 end = (address) dlinfo2.dli_saddr;
3780 Disassembler::decode(begin, end, st);
3781 }
3782 return true;
3783 }
3784 return false;
3785 }
3787 ////////////////////////////////////////////////////////////////////////////////
3788 // misc
3790 // This does not do anything on Bsd. This is basically a hook for being
3791 // able to use structured exception handling (thread-local exception filters)
3792 // on, e.g., Win32.
3793 void
3794 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3795 JavaCallArguments* args, Thread* thread) {
3796 f(value, method, args, thread);
3797 }
3799 void os::print_statistics() {
3800 }
3802 int os::message_box(const char* title, const char* message) {
3803 int i;
3804 fdStream err(defaultStream::error_fd());
3805 for (i = 0; i < 78; i++) err.print_raw("=");
3806 err.cr();
3807 err.print_raw_cr(title);
3808 for (i = 0; i < 78; i++) err.print_raw("-");
3809 err.cr();
3810 err.print_raw_cr(message);
3811 for (i = 0; i < 78; i++) err.print_raw("=");
3812 err.cr();
3814 char buf[16];
3815 // Prevent process from exiting upon "read error" without consuming all CPU
3816 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3818 return buf[0] == 'y' || buf[0] == 'Y';
3819 }
3821 int os::stat(const char *path, struct stat *sbuf) {
3822 char pathbuf[MAX_PATH];
3823 if (strlen(path) > MAX_PATH - 1) {
3824 errno = ENAMETOOLONG;
3825 return -1;
3826 }
3827 os::native_path(strcpy(pathbuf, path));
3828 return ::stat(pathbuf, sbuf);
3829 }
3831 bool os::check_heap(bool force) {
3832 return true;
3833 }
3835 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3836 return ::vsnprintf(buf, count, format, args);
3837 }
3839 // Is a (classpath) directory empty?
3840 bool os::dir_is_empty(const char* path) {
3841 DIR *dir = NULL;
3842 struct dirent *ptr;
3844 dir = opendir(path);
3845 if (dir == NULL) return true;
3847 /* Scan the directory */
3848 bool result = true;
3849 char buf[sizeof(struct dirent) + MAX_PATH];
3850 while (result && (ptr = ::readdir(dir)) != NULL) {
3851 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3852 result = false;
3853 }
3854 }
3855 closedir(dir);
3856 return result;
3857 }
3859 // This code originates from JDK's sysOpen and open64_w
3860 // from src/solaris/hpi/src/system_md.c
3862 #ifndef O_DELETE
3863 #define O_DELETE 0x10000
3864 #endif
3866 // Open a file. Unlink the file immediately after open returns
3867 // if the specified oflag has the O_DELETE flag set.
3868 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3870 int os::open(const char *path, int oflag, int mode) {
3872 if (strlen(path) > MAX_PATH - 1) {
3873 errno = ENAMETOOLONG;
3874 return -1;
3875 }
3876 int fd;
3877 int o_delete = (oflag & O_DELETE);
3878 oflag = oflag & ~O_DELETE;
3880 fd = ::open(path, oflag, mode);
3881 if (fd == -1) return -1;
3883 //If the open succeeded, the file might still be a directory
3884 {
3885 struct stat buf;
3886 int ret = ::fstat(fd, &buf);
3887 int st_mode = buf.st_mode;
3889 if (ret != -1) {
3890 if ((st_mode & S_IFMT) == S_IFDIR) {
3891 errno = EISDIR;
3892 ::close(fd);
3893 return -1;
3894 }
3895 } else {
3896 ::close(fd);
3897 return -1;
3898 }
3899 }
3901 /*
3902 * All file descriptors that are opened in the JVM and not
3903 * specifically destined for a subprocess should have the
3904 * close-on-exec flag set. If we don't set it, then careless 3rd
3905 * party native code might fork and exec without closing all
3906 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3907 * UNIXProcess.c), and this in turn might:
3908 *
3909 * - cause end-of-file to fail to be detected on some file
3910 * descriptors, resulting in mysterious hangs, or
3911 *
3912 * - might cause an fopen in the subprocess to fail on a system
3913 * suffering from bug 1085341.
3914 *
3915 * (Yes, the default setting of the close-on-exec flag is a Unix
3916 * design flaw)
3917 *
3918 * See:
3919 * 1085341: 32-bit stdio routines should support file descriptors >255
3920 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3921 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3922 */
3923 #ifdef FD_CLOEXEC
3924 {
3925 int flags = ::fcntl(fd, F_GETFD);
3926 if (flags != -1)
3927 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3928 }
3929 #endif
3931 if (o_delete != 0) {
3932 ::unlink(path);
3933 }
3934 return fd;
3935 }
3938 // create binary file, rewriting existing file if required
3939 int os::create_binary_file(const char* path, bool rewrite_existing) {
3940 int oflags = O_WRONLY | O_CREAT;
3941 if (!rewrite_existing) {
3942 oflags |= O_EXCL;
3943 }
3944 return ::open(path, oflags, S_IREAD | S_IWRITE);
3945 }
3947 // return current position of file pointer
3948 jlong os::current_file_offset(int fd) {
3949 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3950 }
3952 // move file pointer to the specified offset
3953 jlong os::seek_to_file_offset(int fd, jlong offset) {
3954 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3955 }
3957 // This code originates from JDK's sysAvailable
3958 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3960 int os::available(int fd, jlong *bytes) {
3961 jlong cur, end;
3962 int mode;
3963 struct stat buf;
3965 if (::fstat(fd, &buf) >= 0) {
3966 mode = buf.st_mode;
3967 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3968 /*
3969 * XXX: is the following call interruptible? If so, this might
3970 * need to go through the INTERRUPT_IO() wrapper as for other
3971 * blocking, interruptible calls in this file.
3972 */
3973 int n;
3974 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3975 *bytes = n;
3976 return 1;
3977 }
3978 }
3979 }
3980 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3981 return 0;
3982 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3983 return 0;
3984 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3985 return 0;
3986 }
3987 *bytes = end - cur;
3988 return 1;
3989 }
3991 int os::socket_available(int fd, jint *pbytes) {
3992 if (fd < 0)
3993 return OS_OK;
3995 int ret;
3997 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3999 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4000 // is expected to return 0 on failure and 1 on success to the jdk.
4002 return (ret == OS_ERR) ? 0 : 1;
4003 }
4005 // Map a block of memory.
4006 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4007 char *addr, size_t bytes, bool read_only,
4008 bool allow_exec) {
4009 int prot;
4010 int flags;
4012 if (read_only) {
4013 prot = PROT_READ;
4014 flags = MAP_SHARED;
4015 } else {
4016 prot = PROT_READ | PROT_WRITE;
4017 flags = MAP_PRIVATE;
4018 }
4020 if (allow_exec) {
4021 prot |= PROT_EXEC;
4022 }
4024 if (addr != NULL) {
4025 flags |= MAP_FIXED;
4026 }
4028 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4029 fd, file_offset);
4030 if (mapped_address == MAP_FAILED) {
4031 return NULL;
4032 }
4033 return mapped_address;
4034 }
4037 // Remap a block of memory.
4038 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4039 char *addr, size_t bytes, bool read_only,
4040 bool allow_exec) {
4041 // same as map_memory() on this OS
4042 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4043 allow_exec);
4044 }
4047 // Unmap a block of memory.
4048 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4049 return munmap(addr, bytes) == 0;
4050 }
4052 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4053 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4054 // of a thread.
4055 //
4056 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4057 // the fast estimate available on the platform.
4059 jlong os::current_thread_cpu_time() {
4060 #ifdef __APPLE__
4061 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4062 #else
4063 Unimplemented();
4064 return 0;
4065 #endif
4066 }
4068 jlong os::thread_cpu_time(Thread* thread) {
4069 #ifdef __APPLE__
4070 return os::thread_cpu_time(thread, true /* user + sys */);
4071 #else
4072 Unimplemented();
4073 return 0;
4074 #endif
4075 }
4077 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4078 #ifdef __APPLE__
4079 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4080 #else
4081 Unimplemented();
4082 return 0;
4083 #endif
4084 }
4086 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4087 #ifdef __APPLE__
4088 struct thread_basic_info tinfo;
4089 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4090 kern_return_t kr;
4091 thread_t mach_thread;
4093 mach_thread = thread->osthread()->thread_id();
4094 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4095 if (kr != KERN_SUCCESS)
4096 return -1;
4098 if (user_sys_cpu_time) {
4099 jlong nanos;
4100 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4101 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4102 return nanos;
4103 } else {
4104 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4105 }
4106 #else
4107 Unimplemented();
4108 return 0;
4109 #endif
4110 }
4113 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4114 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4115 info_ptr->may_skip_backward = false; // elapsed time not wall time
4116 info_ptr->may_skip_forward = false; // elapsed time not wall time
4117 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4118 }
4120 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4121 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4122 info_ptr->may_skip_backward = false; // elapsed time not wall time
4123 info_ptr->may_skip_forward = false; // elapsed time not wall time
4124 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4125 }
4127 bool os::is_thread_cpu_time_supported() {
4128 #ifdef __APPLE__
4129 return true;
4130 #else
4131 return false;
4132 #endif
4133 }
4135 // System loadavg support. Returns -1 if load average cannot be obtained.
4136 // Bsd doesn't yet have a (official) notion of processor sets,
4137 // so just return the system wide load average.
4138 int os::loadavg(double loadavg[], int nelem) {
4139 return ::getloadavg(loadavg, nelem);
4140 }
4142 void os::pause() {
4143 char filename[MAX_PATH];
4144 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4145 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4146 } else {
4147 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4148 }
4150 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4151 if (fd != -1) {
4152 struct stat buf;
4153 ::close(fd);
4154 while (::stat(filename, &buf) == 0) {
4155 (void)::poll(NULL, 0, 100);
4156 }
4157 } else {
4158 jio_fprintf(stderr,
4159 "Could not open pause file '%s', continuing immediately.\n", filename);
4160 }
4161 }
4164 // Refer to the comments in os_solaris.cpp park-unpark.
4165 //
4166 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4167 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4168 // For specifics regarding the bug see GLIBC BUGID 261237 :
4169 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4170 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4171 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4172 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4173 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4174 // and monitorenter when we're using 1-0 locking. All those operations may result in
4175 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4176 // of libpthread avoids the problem, but isn't practical.
4177 //
4178 // Possible remedies:
4179 //
4180 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4181 // This is palliative and probabilistic, however. If the thread is preempted
4182 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4183 // than the minimum period may have passed, and the abstime may be stale (in the
4184 // past) resultin in a hang. Using this technique reduces the odds of a hang
4185 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4186 //
4187 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4188 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4189 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4190 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4191 // thread.
4192 //
4193 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4194 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4195 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4196 // This also works well. In fact it avoids kernel-level scalability impediments
4197 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4198 // timers in a graceful fashion.
4199 //
4200 // 4. When the abstime value is in the past it appears that control returns
4201 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4202 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4203 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4204 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4205 // It may be possible to avoid reinitialization by checking the return
4206 // value from pthread_cond_timedwait(). In addition to reinitializing the
4207 // condvar we must establish the invariant that cond_signal() is only called
4208 // within critical sections protected by the adjunct mutex. This prevents
4209 // cond_signal() from "seeing" a condvar that's in the midst of being
4210 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4211 // desirable signal-after-unlock optimization that avoids futile context switching.
4212 //
4213 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4214 // structure when a condvar is used or initialized. cond_destroy() would
4215 // release the helper structure. Our reinitialize-after-timedwait fix
4216 // put excessive stress on malloc/free and locks protecting the c-heap.
4217 //
4218 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4219 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4220 // and only enabling the work-around for vulnerable environments.
4222 // utility to compute the abstime argument to timedwait:
4223 // millis is the relative timeout time
4224 // abstime will be the absolute timeout time
4225 // TODO: replace compute_abstime() with unpackTime()
4227 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4228 if (millis < 0) millis = 0;
4229 struct timeval now;
4230 int status = gettimeofday(&now, NULL);
4231 assert(status == 0, "gettimeofday");
4232 jlong seconds = millis / 1000;
4233 millis %= 1000;
4234 if (seconds > 50000000) { // see man cond_timedwait(3T)
4235 seconds = 50000000;
4236 }
4237 abstime->tv_sec = now.tv_sec + seconds;
4238 long usec = now.tv_usec + millis * 1000;
4239 if (usec >= 1000000) {
4240 abstime->tv_sec += 1;
4241 usec -= 1000000;
4242 }
4243 abstime->tv_nsec = usec * 1000;
4244 return abstime;
4245 }
4248 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4249 // Conceptually TryPark() should be equivalent to park(0).
4251 int os::PlatformEvent::TryPark() {
4252 for (;;) {
4253 const int v = _Event ;
4254 guarantee ((v == 0) || (v == 1), "invariant") ;
4255 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4256 }
4257 }
4259 void os::PlatformEvent::park() { // AKA "down()"
4260 // Invariant: Only the thread associated with the Event/PlatformEvent
4261 // may call park().
4262 // TODO: assert that _Assoc != NULL or _Assoc == Self
4263 int v ;
4264 for (;;) {
4265 v = _Event ;
4266 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4267 }
4268 guarantee (v >= 0, "invariant") ;
4269 if (v == 0) {
4270 // Do this the hard way by blocking ...
4271 int status = pthread_mutex_lock(_mutex);
4272 assert_status(status == 0, status, "mutex_lock");
4273 guarantee (_nParked == 0, "invariant") ;
4274 ++ _nParked ;
4275 while (_Event < 0) {
4276 status = pthread_cond_wait(_cond, _mutex);
4277 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4278 // Treat this the same as if the wait was interrupted
4279 if (status == ETIMEDOUT) { status = EINTR; }
4280 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4281 }
4282 -- _nParked ;
4284 _Event = 0 ;
4285 status = pthread_mutex_unlock(_mutex);
4286 assert_status(status == 0, status, "mutex_unlock");
4287 // Paranoia to ensure our locked and lock-free paths interact
4288 // correctly with each other.
4289 OrderAccess::fence();
4290 }
4291 guarantee (_Event >= 0, "invariant") ;
4292 }
4294 int os::PlatformEvent::park(jlong millis) {
4295 guarantee (_nParked == 0, "invariant") ;
4297 int v ;
4298 for (;;) {
4299 v = _Event ;
4300 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4301 }
4302 guarantee (v >= 0, "invariant") ;
4303 if (v != 0) return OS_OK ;
4305 // We do this the hard way, by blocking the thread.
4306 // Consider enforcing a minimum timeout value.
4307 struct timespec abst;
4308 compute_abstime(&abst, millis);
4310 int ret = OS_TIMEOUT;
4311 int status = pthread_mutex_lock(_mutex);
4312 assert_status(status == 0, status, "mutex_lock");
4313 guarantee (_nParked == 0, "invariant") ;
4314 ++_nParked ;
4316 // Object.wait(timo) will return because of
4317 // (a) notification
4318 // (b) timeout
4319 // (c) thread.interrupt
4320 //
4321 // Thread.interrupt and object.notify{All} both call Event::set.
4322 // That is, we treat thread.interrupt as a special case of notification.
4323 // The underlying Solaris implementation, cond_timedwait, admits
4324 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4325 // JVM from making those visible to Java code. As such, we must
4326 // filter out spurious wakeups. We assume all ETIME returns are valid.
4327 //
4328 // TODO: properly differentiate simultaneous notify+interrupt.
4329 // In that case, we should propagate the notify to another waiter.
4331 while (_Event < 0) {
4332 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4333 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4334 pthread_cond_destroy (_cond);
4335 pthread_cond_init (_cond, NULL) ;
4336 }
4337 assert_status(status == 0 || status == EINTR ||
4338 status == ETIMEDOUT,
4339 status, "cond_timedwait");
4340 if (!FilterSpuriousWakeups) break ; // previous semantics
4341 if (status == ETIMEDOUT) break ;
4342 // We consume and ignore EINTR and spurious wakeups.
4343 }
4344 --_nParked ;
4345 if (_Event >= 0) {
4346 ret = OS_OK;
4347 }
4348 _Event = 0 ;
4349 status = pthread_mutex_unlock(_mutex);
4350 assert_status(status == 0, status, "mutex_unlock");
4351 assert (_nParked == 0, "invariant") ;
4352 // Paranoia to ensure our locked and lock-free paths interact
4353 // correctly with each other.
4354 OrderAccess::fence();
4355 return ret;
4356 }
4358 void os::PlatformEvent::unpark() {
4359 // Transitions for _Event:
4360 // 0 :=> 1
4361 // 1 :=> 1
4362 // -1 :=> either 0 or 1; must signal target thread
4363 // That is, we can safely transition _Event from -1 to either
4364 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4365 // unpark() calls.
4366 // See also: "Semaphores in Plan 9" by Mullender & Cox
4367 //
4368 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4369 // that it will take two back-to-back park() calls for the owning
4370 // thread to block. This has the benefit of forcing a spurious return
4371 // from the first park() call after an unpark() call which will help
4372 // shake out uses of park() and unpark() without condition variables.
4374 if (Atomic::xchg(1, &_Event) >= 0) return;
4376 // Wait for the thread associated with the event to vacate
4377 int status = pthread_mutex_lock(_mutex);
4378 assert_status(status == 0, status, "mutex_lock");
4379 int AnyWaiters = _nParked;
4380 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4381 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4382 AnyWaiters = 0;
4383 pthread_cond_signal(_cond);
4384 }
4385 status = pthread_mutex_unlock(_mutex);
4386 assert_status(status == 0, status, "mutex_unlock");
4387 if (AnyWaiters != 0) {
4388 status = pthread_cond_signal(_cond);
4389 assert_status(status == 0, status, "cond_signal");
4390 }
4392 // Note that we signal() _after dropping the lock for "immortal" Events.
4393 // This is safe and avoids a common class of futile wakeups. In rare
4394 // circumstances this can cause a thread to return prematurely from
4395 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4396 // simply re-test the condition and re-park itself.
4397 }
4400 // JSR166
4401 // -------------------------------------------------------
4403 /*
4404 * The solaris and bsd implementations of park/unpark are fairly
4405 * conservative for now, but can be improved. They currently use a
4406 * mutex/condvar pair, plus a a count.
4407 * Park decrements count if > 0, else does a condvar wait. Unpark
4408 * sets count to 1 and signals condvar. Only one thread ever waits
4409 * on the condvar. Contention seen when trying to park implies that someone
4410 * is unparking you, so don't wait. And spurious returns are fine, so there
4411 * is no need to track notifications.
4412 */
4414 #define MAX_SECS 100000000
4415 /*
4416 * This code is common to bsd and solaris and will be moved to a
4417 * common place in dolphin.
4418 *
4419 * The passed in time value is either a relative time in nanoseconds
4420 * or an absolute time in milliseconds. Either way it has to be unpacked
4421 * into suitable seconds and nanoseconds components and stored in the
4422 * given timespec structure.
4423 * Given time is a 64-bit value and the time_t used in the timespec is only
4424 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4425 * overflow if times way in the future are given. Further on Solaris versions
4426 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4427 * number of seconds, in abstime, is less than current_time + 100,000,000.
4428 * As it will be 28 years before "now + 100000000" will overflow we can
4429 * ignore overflow and just impose a hard-limit on seconds using the value
4430 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4431 * years from "now".
4432 */
4434 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4435 assert (time > 0, "convertTime");
4437 struct timeval now;
4438 int status = gettimeofday(&now, NULL);
4439 assert(status == 0, "gettimeofday");
4441 time_t max_secs = now.tv_sec + MAX_SECS;
4443 if (isAbsolute) {
4444 jlong secs = time / 1000;
4445 if (secs > max_secs) {
4446 absTime->tv_sec = max_secs;
4447 }
4448 else {
4449 absTime->tv_sec = secs;
4450 }
4451 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4452 }
4453 else {
4454 jlong secs = time / NANOSECS_PER_SEC;
4455 if (secs >= MAX_SECS) {
4456 absTime->tv_sec = max_secs;
4457 absTime->tv_nsec = 0;
4458 }
4459 else {
4460 absTime->tv_sec = now.tv_sec + secs;
4461 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4462 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4463 absTime->tv_nsec -= NANOSECS_PER_SEC;
4464 ++absTime->tv_sec; // note: this must be <= max_secs
4465 }
4466 }
4467 }
4468 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4469 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4470 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4471 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4472 }
4474 void Parker::park(bool isAbsolute, jlong time) {
4475 // Ideally we'd do something useful while spinning, such
4476 // as calling unpackTime().
4478 // Optional fast-path check:
4479 // Return immediately if a permit is available.
4480 // We depend on Atomic::xchg() having full barrier semantics
4481 // since we are doing a lock-free update to _counter.
4482 if (Atomic::xchg(0, &_counter) > 0) return;
4484 Thread* thread = Thread::current();
4485 assert(thread->is_Java_thread(), "Must be JavaThread");
4486 JavaThread *jt = (JavaThread *)thread;
4488 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4489 // Check interrupt before trying to wait
4490 if (Thread::is_interrupted(thread, false)) {
4491 return;
4492 }
4494 // Next, demultiplex/decode time arguments
4495 struct timespec absTime;
4496 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4497 return;
4498 }
4499 if (time > 0) {
4500 unpackTime(&absTime, isAbsolute, time);
4501 }
4504 // Enter safepoint region
4505 // Beware of deadlocks such as 6317397.
4506 // The per-thread Parker:: mutex is a classic leaf-lock.
4507 // In particular a thread must never block on the Threads_lock while
4508 // holding the Parker:: mutex. If safepoints are pending both the
4509 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4510 ThreadBlockInVM tbivm(jt);
4512 // Don't wait if cannot get lock since interference arises from
4513 // unblocking. Also. check interrupt before trying wait
4514 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4515 return;
4516 }
4518 int status ;
4519 if (_counter > 0) { // no wait needed
4520 _counter = 0;
4521 status = pthread_mutex_unlock(_mutex);
4522 assert (status == 0, "invariant") ;
4523 // Paranoia to ensure our locked and lock-free paths interact
4524 // correctly with each other and Java-level accesses.
4525 OrderAccess::fence();
4526 return;
4527 }
4529 #ifdef ASSERT
4530 // Don't catch signals while blocked; let the running threads have the signals.
4531 // (This allows a debugger to break into the running thread.)
4532 sigset_t oldsigs;
4533 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4534 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4535 #endif
4537 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4538 jt->set_suspend_equivalent();
4539 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4541 if (time == 0) {
4542 status = pthread_cond_wait (_cond, _mutex) ;
4543 } else {
4544 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4545 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4546 pthread_cond_destroy (_cond) ;
4547 pthread_cond_init (_cond, NULL);
4548 }
4549 }
4550 assert_status(status == 0 || status == EINTR ||
4551 status == ETIMEDOUT,
4552 status, "cond_timedwait");
4554 #ifdef ASSERT
4555 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4556 #endif
4558 _counter = 0 ;
4559 status = pthread_mutex_unlock(_mutex) ;
4560 assert_status(status == 0, status, "invariant") ;
4561 // Paranoia to ensure our locked and lock-free paths interact
4562 // correctly with each other and Java-level accesses.
4563 OrderAccess::fence();
4565 // If externally suspended while waiting, re-suspend
4566 if (jt->handle_special_suspend_equivalent_condition()) {
4567 jt->java_suspend_self();
4568 }
4569 }
4571 void Parker::unpark() {
4572 int s, status ;
4573 status = pthread_mutex_lock(_mutex);
4574 assert (status == 0, "invariant") ;
4575 s = _counter;
4576 _counter = 1;
4577 if (s < 1) {
4578 if (WorkAroundNPTLTimedWaitHang) {
4579 status = pthread_cond_signal (_cond) ;
4580 assert (status == 0, "invariant") ;
4581 status = pthread_mutex_unlock(_mutex);
4582 assert (status == 0, "invariant") ;
4583 } else {
4584 status = pthread_mutex_unlock(_mutex);
4585 assert (status == 0, "invariant") ;
4586 status = pthread_cond_signal (_cond) ;
4587 assert (status == 0, "invariant") ;
4588 }
4589 } else {
4590 pthread_mutex_unlock(_mutex);
4591 assert (status == 0, "invariant") ;
4592 }
4593 }
4596 /* Darwin has no "environ" in a dynamic library. */
4597 #ifdef __APPLE__
4598 #include <crt_externs.h>
4599 #define environ (*_NSGetEnviron())
4600 #else
4601 extern char** environ;
4602 #endif
4604 // Run the specified command in a separate process. Return its exit value,
4605 // or -1 on failure (e.g. can't fork a new process).
4606 // Unlike system(), this function can be called from signal handler. It
4607 // doesn't block SIGINT et al.
4608 int os::fork_and_exec(char* cmd) {
4609 const char * argv[4] = {"sh", "-c", cmd, NULL};
4611 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4612 // pthread_atfork handlers and reset pthread library. All we need is a
4613 // separate process to execve. Make a direct syscall to fork process.
4614 // On IA64 there's no fork syscall, we have to use fork() and hope for
4615 // the best...
4616 pid_t pid = fork();
4618 if (pid < 0) {
4619 // fork failed
4620 return -1;
4622 } else if (pid == 0) {
4623 // child process
4625 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4626 // first to kill every thread on the thread list. Because this list is
4627 // not reset by fork() (see notes above), execve() will instead kill
4628 // every thread in the parent process. We know this is the only thread
4629 // in the new process, so make a system call directly.
4630 // IA64 should use normal execve() from glibc to match the glibc fork()
4631 // above.
4632 execve("/bin/sh", (char* const*)argv, environ);
4634 // execve failed
4635 _exit(-1);
4637 } else {
4638 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4639 // care about the actual exit code, for now.
4641 int status;
4643 // Wait for the child process to exit. This returns immediately if
4644 // the child has already exited. */
4645 while (waitpid(pid, &status, 0) < 0) {
4646 switch (errno) {
4647 case ECHILD: return 0;
4648 case EINTR: break;
4649 default: return -1;
4650 }
4651 }
4653 if (WIFEXITED(status)) {
4654 // The child exited normally; get its exit code.
4655 return WEXITSTATUS(status);
4656 } else if (WIFSIGNALED(status)) {
4657 // The child exited because of a signal
4658 // The best value to return is 0x80 + signal number,
4659 // because that is what all Unix shells do, and because
4660 // it allows callers to distinguish between process exit and
4661 // process death by signal.
4662 return 0x80 + WTERMSIG(status);
4663 } else {
4664 // Unknown exit code; pass it through
4665 return status;
4666 }
4667 }
4668 }
4670 // is_headless_jre()
4671 //
4672 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4673 // in order to report if we are running in a headless jre
4674 //
4675 // Since JDK8 xawt/libmawt.so was moved into the same directory
4676 // as libawt.so, and renamed libawt_xawt.so
4677 //
4678 bool os::is_headless_jre() {
4679 struct stat statbuf;
4680 char buf[MAXPATHLEN];
4681 char libmawtpath[MAXPATHLEN];
4682 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4683 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4684 char *p;
4686 // Get path to libjvm.so
4687 os::jvm_path(buf, sizeof(buf));
4689 // Get rid of libjvm.so
4690 p = strrchr(buf, '/');
4691 if (p == NULL) return false;
4692 else *p = '\0';
4694 // Get rid of client or server
4695 p = strrchr(buf, '/');
4696 if (p == NULL) return false;
4697 else *p = '\0';
4699 // check xawt/libmawt.so
4700 strcpy(libmawtpath, buf);
4701 strcat(libmawtpath, xawtstr);
4702 if (::stat(libmawtpath, &statbuf) == 0) return false;
4704 // check libawt_xawt.so
4705 strcpy(libmawtpath, buf);
4706 strcat(libmawtpath, new_xawtstr);
4707 if (::stat(libmawtpath, &statbuf) == 0) return false;
4709 return true;
4710 }
4712 // Get the default path to the core file
4713 // Returns the length of the string
4714 int os::get_core_path(char* buffer, size_t bufferSize) {
4715 int n = jio_snprintf(buffer, bufferSize, "/cores");
4717 // Truncate if theoretical string was longer than bufferSize
4718 n = MIN2(n, (int)bufferSize);
4720 return n;
4721 }