Fri, 24 Jan 2014 09:28:47 +0100
8028280: ParkEvent leak when running modified runThese which only loads classes
Summary: Use spin lock to manage ParkEvent and PlatformEvent free lists.
Reviewed-by: dholmes, fparain, dcubed, acorn
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>
103 # include <sys/syscall.h>
105 #if defined(__FreeBSD__) || defined(__NetBSD__)
106 # include <elf.h>
107 #endif
109 #ifdef __APPLE__
110 # include <mach/mach.h> // semaphore_* API
111 # include <mach-o/dyld.h>
112 # include <sys/proc_info.h>
113 # include <objc/objc-auto.h>
114 #endif
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
118 #endif
120 #define MAX_PATH (2 * K)
122 // for timer info max values which include all bits
123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
125 #define LARGEPAGES_BIT (1 << 6)
126 ////////////////////////////////////////////////////////////////////////////////
127 // global variables
128 julong os::Bsd::_physical_memory = 0;
131 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
132 pthread_t os::Bsd::_main_thread;
133 int os::Bsd::_page_size = -1;
135 static jlong initial_time_count=0;
137 static int clock_tics_per_sec = 100;
139 // For diagnostics to print a message once. see run_periodic_checks
140 static sigset_t check_signal_done;
141 static bool check_signals = true;
143 static pid_t _initial_pid = 0;
145 /* Signal number used to suspend/resume a thread */
147 /* do not use any signal number less than SIGSEGV, see 4355769 */
148 static int SR_signum = SIGUSR2;
149 sigset_t SR_sigset;
152 ////////////////////////////////////////////////////////////////////////////////
153 // utility functions
155 static int SR_initialize();
156 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
158 julong os::available_memory() {
159 return Bsd::available_memory();
160 }
162 // available here means free
163 julong os::Bsd::available_memory() {
164 uint64_t available = physical_memory() >> 2;
165 #ifdef __APPLE__
166 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
167 vm_statistics64_data_t vmstat;
168 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
169 (host_info64_t)&vmstat, &count);
170 assert(kerr == KERN_SUCCESS,
171 "host_statistics64 failed - check mach_host_self() and count");
172 if (kerr == KERN_SUCCESS) {
173 available = vmstat.free_count * os::vm_page_size();
174 }
175 #endif
176 return available;
177 }
179 julong os::physical_memory() {
180 return Bsd::physical_memory();
181 }
183 ////////////////////////////////////////////////////////////////////////////////
184 // environment support
186 bool os::getenv(const char* name, char* buf, int len) {
187 const char* val = ::getenv(name);
188 if (val != NULL && strlen(val) < (size_t)len) {
189 strcpy(buf, val);
190 return true;
191 }
192 if (len > 0) buf[0] = 0; // return a null string
193 return false;
194 }
197 // Return true if user is running as root.
199 bool os::have_special_privileges() {
200 static bool init = false;
201 static bool privileges = false;
202 if (!init) {
203 privileges = (getuid() != geteuid()) || (getgid() != getegid());
204 init = true;
205 }
206 return privileges;
207 }
211 // Cpu architecture string
212 #if defined(ZERO)
213 static char cpu_arch[] = ZERO_LIBARCH;
214 #elif defined(IA64)
215 static char cpu_arch[] = "ia64";
216 #elif defined(IA32)
217 static char cpu_arch[] = "i386";
218 #elif defined(AMD64)
219 static char cpu_arch[] = "amd64";
220 #elif defined(ARM)
221 static char cpu_arch[] = "arm";
222 #elif defined(PPC)
223 static char cpu_arch[] = "ppc";
224 #elif defined(SPARC)
225 # ifdef _LP64
226 static char cpu_arch[] = "sparcv9";
227 # else
228 static char cpu_arch[] = "sparc";
229 # endif
230 #else
231 #error Add appropriate cpu_arch setting
232 #endif
234 // Compiler variant
235 #ifdef COMPILER2
236 #define COMPILER_VARIANT "server"
237 #else
238 #define COMPILER_VARIANT "client"
239 #endif
242 void os::Bsd::initialize_system_info() {
243 int mib[2];
244 size_t len;
245 int cpu_val;
246 julong mem_val;
248 /* get processors count via hw.ncpus sysctl */
249 mib[0] = CTL_HW;
250 mib[1] = HW_NCPU;
251 len = sizeof(cpu_val);
252 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
253 assert(len == sizeof(cpu_val), "unexpected data size");
254 set_processor_count(cpu_val);
255 }
256 else {
257 set_processor_count(1); // fallback
258 }
260 /* get physical memory via hw.memsize sysctl (hw.memsize is used
261 * since it returns a 64 bit value)
262 */
263 mib[0] = CTL_HW;
265 #if defined (HW_MEMSIZE) // Apple
266 mib[1] = HW_MEMSIZE;
267 #elif defined(HW_PHYSMEM) // Most of BSD
268 mib[1] = HW_PHYSMEM;
269 #elif defined(HW_REALMEM) // Old FreeBSD
270 mib[1] = HW_REALMEM;
271 #else
272 #error No ways to get physmem
273 #endif
275 len = sizeof(mem_val);
276 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
277 assert(len == sizeof(mem_val), "unexpected data size");
278 _physical_memory = mem_val;
279 } else {
280 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
281 }
283 #ifdef __OpenBSD__
284 {
285 // limit _physical_memory memory view on OpenBSD since
286 // datasize rlimit restricts us anyway.
287 struct rlimit limits;
288 getrlimit(RLIMIT_DATA, &limits);
289 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
290 }
291 #endif
292 }
294 #ifdef __APPLE__
295 static const char *get_home() {
296 const char *home_dir = ::getenv("HOME");
297 if ((home_dir == NULL) || (*home_dir == '\0')) {
298 struct passwd *passwd_info = getpwuid(geteuid());
299 if (passwd_info != NULL) {
300 home_dir = passwd_info->pw_dir;
301 }
302 }
304 return home_dir;
305 }
306 #endif
308 void os::init_system_properties_values() {
309 // char arch[12];
310 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
312 // The next steps are taken in the product version:
313 //
314 // Obtain the JAVA_HOME value from the location of libjvm.so.
315 // This library should be located at:
316 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
317 //
318 // If "/jre/lib/" appears at the right place in the path, then we
319 // assume libjvm.so is installed in a JDK and we use this path.
320 //
321 // Otherwise exit with message: "Could not create the Java virtual machine."
322 //
323 // The following extra steps are taken in the debugging version:
324 //
325 // If "/jre/lib/" does NOT appear at the right place in the path
326 // instead of exit check for $JAVA_HOME environment variable.
327 //
328 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
329 // then we append a fake suffix "hotspot/libjvm.so" to this path so
330 // it looks like libjvm.so is installed there
331 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
332 //
333 // Otherwise exit.
334 //
335 // Important note: if the location of libjvm.so changes this
336 // code needs to be changed accordingly.
338 // The next few definitions allow the code to be verbatim:
339 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
340 #define getenv(n) ::getenv(n)
342 /*
343 * See ld(1):
344 * The linker uses the following search paths to locate required
345 * shared libraries:
346 * 1: ...
347 * ...
348 * 7: The default directories, normally /lib and /usr/lib.
349 */
350 #ifndef DEFAULT_LIBPATH
351 #define DEFAULT_LIBPATH "/lib:/usr/lib"
352 #endif
354 #define EXTENSIONS_DIR "/lib/ext"
355 #define ENDORSED_DIR "/lib/endorsed"
356 #define REG_DIR "/usr/java/packages"
358 #ifdef __APPLE__
359 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
360 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
361 const char *user_home_dir = get_home();
362 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
363 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
364 sizeof(SYS_EXTENSIONS_DIRS);
365 #endif
367 {
368 /* sysclasspath, java_home, dll_dir */
369 {
370 char *home_path;
371 char *dll_path;
372 char *pslash;
373 char buf[MAXPATHLEN];
374 os::jvm_path(buf, sizeof(buf));
376 // Found the full path to libjvm.so.
377 // Now cut the path to <java_home>/jre if we can.
378 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
379 pslash = strrchr(buf, '/');
380 if (pslash != NULL)
381 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
382 dll_path = malloc(strlen(buf) + 1);
383 if (dll_path == NULL)
384 return;
385 strcpy(dll_path, buf);
386 Arguments::set_dll_dir(dll_path);
388 if (pslash != NULL) {
389 pslash = strrchr(buf, '/');
390 if (pslash != NULL) {
391 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
392 #ifndef __APPLE__
393 pslash = strrchr(buf, '/');
394 if (pslash != NULL)
395 *pslash = '\0'; /* get rid of /lib */
396 #endif
397 }
398 }
400 home_path = malloc(strlen(buf) + 1);
401 if (home_path == NULL)
402 return;
403 strcpy(home_path, buf);
404 Arguments::set_java_home(home_path);
406 if (!set_boot_path('/', ':'))
407 return;
408 }
410 /*
411 * Where to look for native libraries
412 *
413 * Note: Due to a legacy implementation, most of the library path
414 * is set in the launcher. This was to accomodate linking restrictions
415 * on legacy Bsd implementations (which are no longer supported).
416 * Eventually, all the library path setting will be done here.
417 *
418 * However, to prevent the proliferation of improperly built native
419 * libraries, the new path component /usr/java/packages is added here.
420 * Eventually, all the library path setting will be done here.
421 */
422 {
423 char *ld_library_path;
425 /*
426 * Construct the invariant part of ld_library_path. Note that the
427 * space for the colon and the trailing null are provided by the
428 * nulls included by the sizeof operator (so actually we allocate
429 * a byte more than necessary).
430 */
431 #ifdef __APPLE__
432 ld_library_path = (char *) malloc(system_ext_size);
433 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
434 #else
435 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
436 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
437 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
438 #endif
440 /*
441 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
442 * should always exist (until the legacy problem cited above is
443 * addressed).
444 */
445 #ifdef __APPLE__
446 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
447 char *l = getenv("JAVA_LIBRARY_PATH");
448 if (l != NULL) {
449 char *t = ld_library_path;
450 /* That's +1 for the colon and +1 for the trailing '\0' */
451 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
452 sprintf(ld_library_path, "%s:%s", l, t);
453 free(t);
454 }
456 char *v = getenv("DYLD_LIBRARY_PATH");
457 #else
458 char *v = getenv("LD_LIBRARY_PATH");
459 #endif
460 if (v != NULL) {
461 char *t = ld_library_path;
462 /* That's +1 for the colon and +1 for the trailing '\0' */
463 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
464 sprintf(ld_library_path, "%s:%s", v, t);
465 free(t);
466 }
468 #ifdef __APPLE__
469 // Apple's Java6 has "." at the beginning of java.library.path.
470 // OpenJDK on Windows has "." at the end of java.library.path.
471 // OpenJDK on Linux and Solaris don't have "." in java.library.path
472 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
473 // "." is appended to the end of java.library.path. Yes, this
474 // could cause a change in behavior, but Apple's Java6 behavior
475 // can be achieved by putting "." at the beginning of the
476 // JAVA_LIBRARY_PATH environment variable.
477 {
478 char *t = ld_library_path;
479 // that's +3 for appending ":." and the trailing '\0'
480 ld_library_path = (char *) malloc(strlen(t) + 3);
481 sprintf(ld_library_path, "%s:%s", t, ".");
482 free(t);
483 }
484 #endif
486 Arguments::set_library_path(ld_library_path);
487 }
489 /*
490 * Extensions directories.
491 *
492 * Note that the space for the colon and the trailing null are provided
493 * by the nulls included by the sizeof operator (so actually one byte more
494 * than necessary is allocated).
495 */
496 {
497 #ifdef __APPLE__
498 char *buf = malloc(strlen(Arguments::get_java_home()) +
499 sizeof(EXTENSIONS_DIR) + system_ext_size);
500 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
501 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
502 #else
503 char *buf = malloc(strlen(Arguments::get_java_home()) +
504 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
505 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
506 Arguments::get_java_home());
507 #endif
509 Arguments::set_ext_dirs(buf);
510 }
512 /* Endorsed standards default directory. */
513 {
514 char * buf;
515 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
516 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
517 Arguments::set_endorsed_dirs(buf);
518 }
519 }
521 #ifdef __APPLE__
522 #undef SYS_EXTENSIONS_DIR
523 #endif
524 #undef malloc
525 #undef getenv
526 #undef EXTENSIONS_DIR
527 #undef ENDORSED_DIR
529 // Done
530 return;
531 }
533 ////////////////////////////////////////////////////////////////////////////////
534 // breakpoint support
536 void os::breakpoint() {
537 BREAKPOINT;
538 }
540 extern "C" void breakpoint() {
541 // use debugger to set breakpoint here
542 }
544 ////////////////////////////////////////////////////////////////////////////////
545 // signal support
547 debug_only(static bool signal_sets_initialized = false);
548 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
550 bool os::Bsd::is_sig_ignored(int sig) {
551 struct sigaction oact;
552 sigaction(sig, (struct sigaction*)NULL, &oact);
553 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
554 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
555 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
556 return true;
557 else
558 return false;
559 }
561 void os::Bsd::signal_sets_init() {
562 // Should also have an assertion stating we are still single-threaded.
563 assert(!signal_sets_initialized, "Already initialized");
564 // Fill in signals that are necessarily unblocked for all threads in
565 // the VM. Currently, we unblock the following signals:
566 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
567 // by -Xrs (=ReduceSignalUsage));
568 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
569 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
570 // the dispositions or masks wrt these signals.
571 // Programs embedding the VM that want to use the above signals for their
572 // own purposes must, at this time, use the "-Xrs" option to prevent
573 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
574 // (See bug 4345157, and other related bugs).
575 // In reality, though, unblocking these signals is really a nop, since
576 // these signals are not blocked by default.
577 sigemptyset(&unblocked_sigs);
578 sigemptyset(&allowdebug_blocked_sigs);
579 sigaddset(&unblocked_sigs, SIGILL);
580 sigaddset(&unblocked_sigs, SIGSEGV);
581 sigaddset(&unblocked_sigs, SIGBUS);
582 sigaddset(&unblocked_sigs, SIGFPE);
583 sigaddset(&unblocked_sigs, SR_signum);
585 if (!ReduceSignalUsage) {
586 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
587 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
588 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
589 }
590 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
591 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
592 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
593 }
594 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
595 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
596 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
597 }
598 }
599 // Fill in signals that are blocked by all but the VM thread.
600 sigemptyset(&vm_sigs);
601 if (!ReduceSignalUsage)
602 sigaddset(&vm_sigs, BREAK_SIGNAL);
603 debug_only(signal_sets_initialized = true);
605 }
607 // These are signals that are unblocked while a thread is running Java.
608 // (For some reason, they get blocked by default.)
609 sigset_t* os::Bsd::unblocked_signals() {
610 assert(signal_sets_initialized, "Not initialized");
611 return &unblocked_sigs;
612 }
614 // These are the signals that are blocked while a (non-VM) thread is
615 // running Java. Only the VM thread handles these signals.
616 sigset_t* os::Bsd::vm_signals() {
617 assert(signal_sets_initialized, "Not initialized");
618 return &vm_sigs;
619 }
621 // These are signals that are blocked during cond_wait to allow debugger in
622 sigset_t* os::Bsd::allowdebug_blocked_signals() {
623 assert(signal_sets_initialized, "Not initialized");
624 return &allowdebug_blocked_sigs;
625 }
627 void os::Bsd::hotspot_sigmask(Thread* thread) {
629 //Save caller's signal mask before setting VM signal mask
630 sigset_t caller_sigmask;
631 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
633 OSThread* osthread = thread->osthread();
634 osthread->set_caller_sigmask(caller_sigmask);
636 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
638 if (!ReduceSignalUsage) {
639 if (thread->is_VM_thread()) {
640 // Only the VM thread handles BREAK_SIGNAL ...
641 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
642 } else {
643 // ... all other threads block BREAK_SIGNAL
644 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
645 }
646 }
647 }
650 //////////////////////////////////////////////////////////////////////////////
651 // create new thread
653 // check if it's safe to start a new thread
654 static bool _thread_safety_check(Thread* thread) {
655 return true;
656 }
658 #ifdef __APPLE__
659 // library handle for calling objc_registerThreadWithCollector()
660 // without static linking to the libobjc library
661 #define OBJC_LIB "/usr/lib/libobjc.dylib"
662 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
663 typedef void (*objc_registerThreadWithCollector_t)();
664 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
665 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
666 #endif
668 #ifdef __APPLE__
669 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
670 // Additional thread_id used to correlate threads in SA
671 thread_identifier_info_data_t m_ident_info;
672 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
674 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
675 (thread_info_t) &m_ident_info, &count);
677 return m_ident_info.thread_id;
678 }
679 #endif
681 // Thread start routine for all newly created threads
682 static void *java_start(Thread *thread) {
683 // Try to randomize the cache line index of hot stack frames.
684 // This helps when threads of the same stack traces evict each other's
685 // cache lines. The threads can be either from the same JVM instance, or
686 // from different JVM instances. The benefit is especially true for
687 // processors with hyperthreading technology.
688 static int counter = 0;
689 int pid = os::current_process_id();
690 alloca(((pid ^ counter++) & 7) * 128);
692 ThreadLocalStorage::set_thread(thread);
694 OSThread* osthread = thread->osthread();
695 Monitor* sync = osthread->startThread_lock();
697 // non floating stack BsdThreads needs extra check, see above
698 if (!_thread_safety_check(thread)) {
699 // notify parent thread
700 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
701 osthread->set_state(ZOMBIE);
702 sync->notify_all();
703 return NULL;
704 }
706 osthread->set_thread_id(os::Bsd::gettid());
708 #ifdef __APPLE__
709 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
710 guarantee(unique_thread_id != 0, "unique thread id was not found");
711 osthread->set_unique_thread_id(unique_thread_id);
712 #endif
713 // initialize signal mask for this thread
714 os::Bsd::hotspot_sigmask(thread);
716 // initialize floating point control register
717 os::Bsd::init_thread_fpu_state();
719 #ifdef __APPLE__
720 // register thread with objc gc
721 if (objc_registerThreadWithCollectorFunction != NULL) {
722 objc_registerThreadWithCollectorFunction();
723 }
724 #endif
726 // handshaking with parent thread
727 {
728 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
730 // notify parent thread
731 osthread->set_state(INITIALIZED);
732 sync->notify_all();
734 // wait until os::start_thread()
735 while (osthread->get_state() == INITIALIZED) {
736 sync->wait(Mutex::_no_safepoint_check_flag);
737 }
738 }
740 // call one more level start routine
741 thread->run();
743 return 0;
744 }
746 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
747 assert(thread->osthread() == NULL, "caller responsible");
749 // Allocate the OSThread object
750 OSThread* osthread = new OSThread(NULL, NULL);
751 if (osthread == NULL) {
752 return false;
753 }
755 // set the correct thread state
756 osthread->set_thread_type(thr_type);
758 // Initial state is ALLOCATED but not INITIALIZED
759 osthread->set_state(ALLOCATED);
761 thread->set_osthread(osthread);
763 // init thread attributes
764 pthread_attr_t attr;
765 pthread_attr_init(&attr);
766 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
768 // stack size
769 if (os::Bsd::supports_variable_stack_size()) {
770 // calculate stack size if it's not specified by caller
771 if (stack_size == 0) {
772 stack_size = os::Bsd::default_stack_size(thr_type);
774 switch (thr_type) {
775 case os::java_thread:
776 // Java threads use ThreadStackSize which default value can be
777 // changed with the flag -Xss
778 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
779 stack_size = JavaThread::stack_size_at_create();
780 break;
781 case os::compiler_thread:
782 if (CompilerThreadStackSize > 0) {
783 stack_size = (size_t)(CompilerThreadStackSize * K);
784 break;
785 } // else fall through:
786 // use VMThreadStackSize if CompilerThreadStackSize is not defined
787 case os::vm_thread:
788 case os::pgc_thread:
789 case os::cgc_thread:
790 case os::watcher_thread:
791 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
792 break;
793 }
794 }
796 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
797 pthread_attr_setstacksize(&attr, stack_size);
798 } else {
799 // let pthread_create() pick the default value.
800 }
802 ThreadState state;
804 {
805 pthread_t tid;
806 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
808 pthread_attr_destroy(&attr);
810 if (ret != 0) {
811 if (PrintMiscellaneous && (Verbose || WizardMode)) {
812 perror("pthread_create()");
813 }
814 // Need to clean up stuff we've allocated so far
815 thread->set_osthread(NULL);
816 delete osthread;
817 return false;
818 }
820 // Store pthread info into the OSThread
821 osthread->set_pthread_id(tid);
823 // Wait until child thread is either initialized or aborted
824 {
825 Monitor* sync_with_child = osthread->startThread_lock();
826 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
827 while ((state = osthread->get_state()) == ALLOCATED) {
828 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
829 }
830 }
832 }
834 // Aborted due to thread limit being reached
835 if (state == ZOMBIE) {
836 thread->set_osthread(NULL);
837 delete osthread;
838 return false;
839 }
841 // The thread is returned suspended (in state INITIALIZED),
842 // and is started higher up in the call chain
843 assert(state == INITIALIZED, "race condition");
844 return true;
845 }
847 /////////////////////////////////////////////////////////////////////////////
848 // attach existing thread
850 // bootstrap the main thread
851 bool os::create_main_thread(JavaThread* thread) {
852 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
853 return create_attached_thread(thread);
854 }
856 bool os::create_attached_thread(JavaThread* thread) {
857 #ifdef ASSERT
858 thread->verify_not_published();
859 #endif
861 // Allocate the OSThread object
862 OSThread* osthread = new OSThread(NULL, NULL);
864 if (osthread == NULL) {
865 return false;
866 }
868 osthread->set_thread_id(os::Bsd::gettid());
870 // Store pthread info into the OSThread
871 #ifdef __APPLE__
872 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
873 guarantee(unique_thread_id != 0, "just checking");
874 osthread->set_unique_thread_id(unique_thread_id);
875 #endif
876 osthread->set_pthread_id(::pthread_self());
878 // initialize floating point control register
879 os::Bsd::init_thread_fpu_state();
881 // Initial thread state is RUNNABLE
882 osthread->set_state(RUNNABLE);
884 thread->set_osthread(osthread);
886 // initialize signal mask for this thread
887 // and save the caller's signal mask
888 os::Bsd::hotspot_sigmask(thread);
890 return true;
891 }
893 void os::pd_start_thread(Thread* thread) {
894 OSThread * osthread = thread->osthread();
895 assert(osthread->get_state() != INITIALIZED, "just checking");
896 Monitor* sync_with_child = osthread->startThread_lock();
897 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
898 sync_with_child->notify();
899 }
901 // Free Bsd resources related to the OSThread
902 void os::free_thread(OSThread* osthread) {
903 assert(osthread != NULL, "osthread not set");
905 if (Thread::current()->osthread() == osthread) {
906 // Restore caller's signal mask
907 sigset_t sigmask = osthread->caller_sigmask();
908 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
909 }
911 delete osthread;
912 }
914 //////////////////////////////////////////////////////////////////////////////
915 // thread local storage
917 int os::allocate_thread_local_storage() {
918 pthread_key_t key;
919 int rslt = pthread_key_create(&key, NULL);
920 assert(rslt == 0, "cannot allocate thread local storage");
921 return (int)key;
922 }
924 // Note: This is currently not used by VM, as we don't destroy TLS key
925 // on VM exit.
926 void os::free_thread_local_storage(int index) {
927 int rslt = pthread_key_delete((pthread_key_t)index);
928 assert(rslt == 0, "invalid index");
929 }
931 void os::thread_local_storage_at_put(int index, void* value) {
932 int rslt = pthread_setspecific((pthread_key_t)index, value);
933 assert(rslt == 0, "pthread_setspecific failed");
934 }
936 extern "C" Thread* get_thread() {
937 return ThreadLocalStorage::thread();
938 }
941 ////////////////////////////////////////////////////////////////////////////////
942 // time support
944 // Time since start-up in seconds to a fine granularity.
945 // Used by VMSelfDestructTimer and the MemProfiler.
946 double os::elapsedTime() {
948 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
949 }
951 jlong os::elapsed_counter() {
952 return javaTimeNanos() - initial_time_count;
953 }
955 jlong os::elapsed_frequency() {
956 return NANOSECS_PER_SEC; // nanosecond resolution
957 }
959 bool os::supports_vtime() { return true; }
960 bool os::enable_vtime() { return false; }
961 bool os::vtime_enabled() { return false; }
963 double os::elapsedVTime() {
964 // better than nothing, but not much
965 return elapsedTime();
966 }
968 jlong os::javaTimeMillis() {
969 timeval time;
970 int status = gettimeofday(&time, NULL);
971 assert(status != -1, "bsd error");
972 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
973 }
975 #ifndef CLOCK_MONOTONIC
976 #define CLOCK_MONOTONIC (1)
977 #endif
979 #ifdef __APPLE__
980 void os::Bsd::clock_init() {
981 // XXXDARWIN: Investigate replacement monotonic clock
982 }
983 #else
984 void os::Bsd::clock_init() {
985 struct timespec res;
986 struct timespec tp;
987 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
988 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
989 // yes, monotonic clock is supported
990 _clock_gettime = ::clock_gettime;
991 }
992 }
993 #endif
996 jlong os::javaTimeNanos() {
997 if (Bsd::supports_monotonic_clock()) {
998 struct timespec tp;
999 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1000 assert(status == 0, "gettime error");
1001 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1002 return result;
1003 } else {
1004 timeval time;
1005 int status = gettimeofday(&time, NULL);
1006 assert(status != -1, "bsd error");
1007 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1008 return 1000 * usecs;
1009 }
1010 }
1012 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1013 if (Bsd::supports_monotonic_clock()) {
1014 info_ptr->max_value = ALL_64_BITS;
1016 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1017 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1018 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1019 } else {
1020 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1021 info_ptr->max_value = ALL_64_BITS;
1023 // gettimeofday is a real time clock so it skips
1024 info_ptr->may_skip_backward = true;
1025 info_ptr->may_skip_forward = true;
1026 }
1028 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1029 }
1031 // Return the real, user, and system times in seconds from an
1032 // arbitrary fixed point in the past.
1033 bool os::getTimesSecs(double* process_real_time,
1034 double* process_user_time,
1035 double* process_system_time) {
1036 struct tms ticks;
1037 clock_t real_ticks = times(&ticks);
1039 if (real_ticks == (clock_t) (-1)) {
1040 return false;
1041 } else {
1042 double ticks_per_second = (double) clock_tics_per_sec;
1043 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1044 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1045 *process_real_time = ((double) real_ticks) / ticks_per_second;
1047 return true;
1048 }
1049 }
1052 char * os::local_time_string(char *buf, size_t buflen) {
1053 struct tm t;
1054 time_t long_time;
1055 time(&long_time);
1056 localtime_r(&long_time, &t);
1057 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1058 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1059 t.tm_hour, t.tm_min, t.tm_sec);
1060 return buf;
1061 }
1063 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1064 return localtime_r(clock, res);
1065 }
1067 ////////////////////////////////////////////////////////////////////////////////
1068 // runtime exit support
1070 // Note: os::shutdown() might be called very early during initialization, or
1071 // called from signal handler. Before adding something to os::shutdown(), make
1072 // sure it is async-safe and can handle partially initialized VM.
1073 void os::shutdown() {
1075 // allow PerfMemory to attempt cleanup of any persistent resources
1076 perfMemory_exit();
1078 // needs to remove object in file system
1079 AttachListener::abort();
1081 // flush buffered output, finish log files
1082 ostream_abort();
1084 // Check for abort hook
1085 abort_hook_t abort_hook = Arguments::abort_hook();
1086 if (abort_hook != NULL) {
1087 abort_hook();
1088 }
1090 }
1092 // Note: os::abort() might be called very early during initialization, or
1093 // called from signal handler. Before adding something to os::abort(), make
1094 // sure it is async-safe and can handle partially initialized VM.
1095 void os::abort(bool dump_core) {
1096 os::shutdown();
1097 if (dump_core) {
1098 #ifndef PRODUCT
1099 fdStream out(defaultStream::output_fd());
1100 out.print_raw("Current thread is ");
1101 char buf[16];
1102 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1103 out.print_raw_cr(buf);
1104 out.print_raw_cr("Dumping core ...");
1105 #endif
1106 ::abort(); // dump core
1107 }
1109 ::exit(1);
1110 }
1112 // Die immediately, no exit hook, no abort hook, no cleanup.
1113 void os::die() {
1114 // _exit() on BsdThreads only kills current thread
1115 ::abort();
1116 }
1118 // unused on bsd for now.
1119 void os::set_error_file(const char *logfile) {}
1122 // This method is a copy of JDK's sysGetLastErrorString
1123 // from src/solaris/hpi/src/system_md.c
1125 size_t os::lasterror(char *buf, size_t len) {
1127 if (errno == 0) return 0;
1129 const char *s = ::strerror(errno);
1130 size_t n = ::strlen(s);
1131 if (n >= len) {
1132 n = len - 1;
1133 }
1134 ::strncpy(buf, s, n);
1135 buf[n] = '\0';
1136 return n;
1137 }
1139 // Information of current thread in variety of formats
1140 pid_t os::Bsd::gettid() {
1141 int retval = -1;
1143 #ifdef __APPLE__ //XNU kernel
1144 // despite the fact mach port is actually not a thread id use it
1145 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1146 retval = ::pthread_mach_thread_np(::pthread_self());
1147 guarantee(retval != 0, "just checking");
1148 return retval;
1150 #elif __FreeBSD__
1151 retval = syscall(SYS_thr_self);
1152 #elif __OpenBSD__
1153 retval = syscall(SYS_getthrid);
1154 #elif __NetBSD__
1155 retval = (pid_t) syscall(SYS__lwp_self);
1156 #endif
1158 if (retval == -1) {
1159 return getpid();
1160 }
1161 }
1163 intx os::current_thread_id() {
1164 #ifdef __APPLE__
1165 return (intx)::pthread_mach_thread_np(::pthread_self());
1166 #else
1167 return (intx)::pthread_self();
1168 #endif
1169 }
1171 int os::current_process_id() {
1173 // Under the old bsd thread library, bsd gives each thread
1174 // its own process id. Because of this each thread will return
1175 // a different pid if this method were to return the result
1176 // of getpid(2). Bsd provides no api that returns the pid
1177 // of the launcher thread for the vm. This implementation
1178 // returns a unique pid, the pid of the launcher thread
1179 // that starts the vm 'process'.
1181 // Under the NPTL, getpid() returns the same pid as the
1182 // launcher thread rather than a unique pid per thread.
1183 // Use gettid() if you want the old pre NPTL behaviour.
1185 // if you are looking for the result of a call to getpid() that
1186 // returns a unique pid for the calling thread, then look at the
1187 // OSThread::thread_id() method in osThread_bsd.hpp file
1189 return (int)(_initial_pid ? _initial_pid : getpid());
1190 }
1192 // DLL functions
1194 #define JNI_LIB_PREFIX "lib"
1195 #ifdef __APPLE__
1196 #define JNI_LIB_SUFFIX ".dylib"
1197 #else
1198 #define JNI_LIB_SUFFIX ".so"
1199 #endif
1201 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1203 // This must be hard coded because it's the system's temporary
1204 // directory not the java application's temp directory, ala java.io.tmpdir.
1205 #ifdef __APPLE__
1206 // macosx has a secure per-user temporary directory
1207 char temp_path_storage[PATH_MAX];
1208 const char* os::get_temp_directory() {
1209 static char *temp_path = NULL;
1210 if (temp_path == NULL) {
1211 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1212 if (pathSize == 0 || pathSize > PATH_MAX) {
1213 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1214 }
1215 temp_path = temp_path_storage;
1216 }
1217 return temp_path;
1218 }
1219 #else /* __APPLE__ */
1220 const char* os::get_temp_directory() { return "/tmp"; }
1221 #endif /* __APPLE__ */
1223 static bool file_exists(const char* filename) {
1224 struct stat statbuf;
1225 if (filename == NULL || strlen(filename) == 0) {
1226 return false;
1227 }
1228 return os::stat(filename, &statbuf) == 0;
1229 }
1231 bool os::dll_build_name(char* buffer, size_t buflen,
1232 const char* pname, const char* fname) {
1233 bool retval = false;
1234 // Copied from libhpi
1235 const size_t pnamelen = pname ? strlen(pname) : 0;
1237 // Return error on buffer overflow.
1238 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1239 return retval;
1240 }
1242 if (pnamelen == 0) {
1243 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1244 retval = true;
1245 } else if (strchr(pname, *os::path_separator()) != NULL) {
1246 int n;
1247 char** pelements = split_path(pname, &n);
1248 if (pelements == NULL) {
1249 return false;
1250 }
1251 for (int i = 0 ; i < n ; i++) {
1252 // Really shouldn't be NULL, but check can't hurt
1253 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1254 continue; // skip the empty path values
1255 }
1256 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1257 pelements[i], fname);
1258 if (file_exists(buffer)) {
1259 retval = true;
1260 break;
1261 }
1262 }
1263 // release the storage
1264 for (int i = 0 ; i < n ; i++) {
1265 if (pelements[i] != NULL) {
1266 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1267 }
1268 }
1269 if (pelements != NULL) {
1270 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1271 }
1272 } else {
1273 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1274 retval = true;
1275 }
1276 return retval;
1277 }
1279 // check if addr is inside libjvm.so
1280 bool os::address_is_in_vm(address addr) {
1281 static address libjvm_base_addr;
1282 Dl_info dlinfo;
1284 if (libjvm_base_addr == NULL) {
1285 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1286 libjvm_base_addr = (address)dlinfo.dli_fbase;
1287 }
1288 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1289 }
1291 if (dladdr((void *)addr, &dlinfo) != 0) {
1292 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1293 }
1295 return false;
1296 }
1299 #define MACH_MAXSYMLEN 256
1301 bool os::dll_address_to_function_name(address addr, char *buf,
1302 int buflen, int *offset) {
1303 // buf is not optional, but offset is optional
1304 assert(buf != NULL, "sanity check");
1306 Dl_info dlinfo;
1307 char localbuf[MACH_MAXSYMLEN];
1309 if (dladdr((void*)addr, &dlinfo) != 0) {
1310 // see if we have a matching symbol
1311 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1312 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1313 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1314 }
1315 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1316 return true;
1317 }
1318 // no matching symbol so try for just file info
1319 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1320 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1321 buf, buflen, offset, dlinfo.dli_fname)) {
1322 return true;
1323 }
1324 }
1326 // Handle non-dynamic manually:
1327 if (dlinfo.dli_fbase != NULL &&
1328 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1329 dlinfo.dli_fbase)) {
1330 if (!Decoder::demangle(localbuf, buf, buflen)) {
1331 jio_snprintf(buf, buflen, "%s", localbuf);
1332 }
1333 return true;
1334 }
1335 }
1336 buf[0] = '\0';
1337 if (offset != NULL) *offset = -1;
1338 return false;
1339 }
1341 // ported from solaris version
1342 bool os::dll_address_to_library_name(address addr, char* buf,
1343 int buflen, int* offset) {
1344 // buf is not optional, but offset is optional
1345 assert(buf != NULL, "sanity check");
1347 Dl_info dlinfo;
1349 if (dladdr((void*)addr, &dlinfo) != 0) {
1350 if (dlinfo.dli_fname != NULL) {
1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1352 }
1353 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1354 *offset = addr - (address)dlinfo.dli_fbase;
1355 }
1356 return true;
1357 }
1359 buf[0] = '\0';
1360 if (offset) *offset = -1;
1361 return false;
1362 }
1364 // Loads .dll/.so and
1365 // in case of error it checks if .dll/.so was built for the
1366 // same architecture as Hotspot is running on
1368 #ifdef __APPLE__
1369 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1370 void * result= ::dlopen(filename, RTLD_LAZY);
1371 if (result != NULL) {
1372 // Successful loading
1373 return result;
1374 }
1376 // Read system error message into ebuf
1377 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1378 ebuf[ebuflen-1]='\0';
1380 return NULL;
1381 }
1382 #else
1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1384 {
1385 void * result= ::dlopen(filename, RTLD_LAZY);
1386 if (result != NULL) {
1387 // Successful loading
1388 return result;
1389 }
1391 Elf32_Ehdr elf_head;
1393 // Read system error message into ebuf
1394 // It may or may not be overwritten below
1395 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1396 ebuf[ebuflen-1]='\0';
1397 int diag_msg_max_length=ebuflen-strlen(ebuf);
1398 char* diag_msg_buf=ebuf+strlen(ebuf);
1400 if (diag_msg_max_length==0) {
1401 // No more space in ebuf for additional diagnostics message
1402 return NULL;
1403 }
1406 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1408 if (file_descriptor < 0) {
1409 // Can't open library, report dlerror() message
1410 return NULL;
1411 }
1413 bool failed_to_read_elf_head=
1414 (sizeof(elf_head)!=
1415 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1417 ::close(file_descriptor);
1418 if (failed_to_read_elf_head) {
1419 // file i/o error - report dlerror() msg
1420 return NULL;
1421 }
1423 typedef struct {
1424 Elf32_Half code; // Actual value as defined in elf.h
1425 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1426 char elf_class; // 32 or 64 bit
1427 char endianess; // MSB or LSB
1428 char* name; // String representation
1429 } arch_t;
1431 #ifndef EM_486
1432 #define EM_486 6 /* Intel 80486 */
1433 #endif
1435 #ifndef EM_MIPS_RS3_LE
1436 #define EM_MIPS_RS3_LE 10 /* MIPS */
1437 #endif
1439 #ifndef EM_PPC64
1440 #define EM_PPC64 21 /* PowerPC64 */
1441 #endif
1443 #ifndef EM_S390
1444 #define EM_S390 22 /* IBM System/390 */
1445 #endif
1447 #ifndef EM_IA_64
1448 #define EM_IA_64 50 /* HP/Intel IA-64 */
1449 #endif
1451 #ifndef EM_X86_64
1452 #define EM_X86_64 62 /* AMD x86-64 */
1453 #endif
1455 static const arch_t arch_array[]={
1456 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1457 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1458 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1459 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1460 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1461 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1462 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1463 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1464 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1465 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1466 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1467 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1468 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1469 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1470 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1471 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1472 };
1474 #if (defined IA32)
1475 static Elf32_Half running_arch_code=EM_386;
1476 #elif (defined AMD64)
1477 static Elf32_Half running_arch_code=EM_X86_64;
1478 #elif (defined IA64)
1479 static Elf32_Half running_arch_code=EM_IA_64;
1480 #elif (defined __sparc) && (defined _LP64)
1481 static Elf32_Half running_arch_code=EM_SPARCV9;
1482 #elif (defined __sparc) && (!defined _LP64)
1483 static Elf32_Half running_arch_code=EM_SPARC;
1484 #elif (defined __powerpc64__)
1485 static Elf32_Half running_arch_code=EM_PPC64;
1486 #elif (defined __powerpc__)
1487 static Elf32_Half running_arch_code=EM_PPC;
1488 #elif (defined ARM)
1489 static Elf32_Half running_arch_code=EM_ARM;
1490 #elif (defined S390)
1491 static Elf32_Half running_arch_code=EM_S390;
1492 #elif (defined ALPHA)
1493 static Elf32_Half running_arch_code=EM_ALPHA;
1494 #elif (defined MIPSEL)
1495 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1496 #elif (defined PARISC)
1497 static Elf32_Half running_arch_code=EM_PARISC;
1498 #elif (defined MIPS)
1499 static Elf32_Half running_arch_code=EM_MIPS;
1500 #elif (defined M68K)
1501 static Elf32_Half running_arch_code=EM_68K;
1502 #else
1503 #error Method os::dll_load requires that one of following is defined:\
1504 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1505 #endif
1507 // Identify compatability class for VM's architecture and library's architecture
1508 // Obtain string descriptions for architectures
1510 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1511 int running_arch_index=-1;
1513 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1514 if (running_arch_code == arch_array[i].code) {
1515 running_arch_index = i;
1516 }
1517 if (lib_arch.code == arch_array[i].code) {
1518 lib_arch.compat_class = arch_array[i].compat_class;
1519 lib_arch.name = arch_array[i].name;
1520 }
1521 }
1523 assert(running_arch_index != -1,
1524 "Didn't find running architecture code (running_arch_code) in arch_array");
1525 if (running_arch_index == -1) {
1526 // Even though running architecture detection failed
1527 // we may still continue with reporting dlerror() message
1528 return NULL;
1529 }
1531 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1532 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1533 return NULL;
1534 }
1536 #ifndef S390
1537 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1539 return NULL;
1540 }
1541 #endif // !S390
1543 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1544 if ( lib_arch.name!=NULL ) {
1545 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1546 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1547 lib_arch.name, arch_array[running_arch_index].name);
1548 } else {
1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1550 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1551 lib_arch.code,
1552 arch_array[running_arch_index].name);
1553 }
1554 }
1556 return NULL;
1557 }
1558 #endif /* !__APPLE__ */
1560 void* os::get_default_process_handle() {
1561 #ifdef __APPLE__
1562 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1563 // to avoid finding unexpected symbols on second (or later)
1564 // loads of a library.
1565 return (void*)::dlopen(NULL, RTLD_FIRST);
1566 #else
1567 return (void*)::dlopen(NULL, RTLD_LAZY);
1568 #endif
1569 }
1571 // XXX: Do we need a lock around this as per Linux?
1572 void* os::dll_lookup(void* handle, const char* name) {
1573 return dlsym(handle, name);
1574 }
1577 static bool _print_ascii_file(const char* filename, outputStream* st) {
1578 int fd = ::open(filename, O_RDONLY);
1579 if (fd == -1) {
1580 return false;
1581 }
1583 char buf[32];
1584 int bytes;
1585 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1586 st->print_raw(buf, bytes);
1587 }
1589 ::close(fd);
1591 return true;
1592 }
1594 void os::print_dll_info(outputStream *st) {
1595 st->print_cr("Dynamic libraries:");
1596 #ifdef RTLD_DI_LINKMAP
1597 Dl_info dli;
1598 void *handle;
1599 Link_map *map;
1600 Link_map *p;
1602 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1603 dli.dli_fname == NULL) {
1604 st->print_cr("Error: Cannot print dynamic libraries.");
1605 return;
1606 }
1607 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1608 if (handle == NULL) {
1609 st->print_cr("Error: Cannot print dynamic libraries.");
1610 return;
1611 }
1612 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1613 if (map == NULL) {
1614 st->print_cr("Error: Cannot print dynamic libraries.");
1615 return;
1616 }
1618 while (map->l_prev != NULL)
1619 map = map->l_prev;
1621 while (map != NULL) {
1622 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1623 map = map->l_next;
1624 }
1626 dlclose(handle);
1627 #elif defined(__APPLE__)
1628 uint32_t count;
1629 uint32_t i;
1631 count = _dyld_image_count();
1632 for (i = 1; i < count; i++) {
1633 const char *name = _dyld_get_image_name(i);
1634 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1635 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1636 }
1637 #else
1638 st->print_cr("Error: Cannot print dynamic libraries.");
1639 #endif
1640 }
1642 void os::print_os_info_brief(outputStream* st) {
1643 st->print("Bsd");
1645 os::Posix::print_uname_info(st);
1646 }
1648 void os::print_os_info(outputStream* st) {
1649 st->print("OS:");
1650 st->print("Bsd");
1652 os::Posix::print_uname_info(st);
1654 os::Posix::print_rlimit_info(st);
1656 os::Posix::print_load_average(st);
1657 }
1659 void os::pd_print_cpu_info(outputStream* st) {
1660 // Nothing to do for now.
1661 }
1663 void os::print_memory_info(outputStream* st) {
1665 st->print("Memory:");
1666 st->print(" %dk page", os::vm_page_size()>>10);
1668 st->print(", physical " UINT64_FORMAT "k",
1669 os::physical_memory() >> 10);
1670 st->print("(" UINT64_FORMAT "k free)",
1671 os::available_memory() >> 10);
1672 st->cr();
1674 // meminfo
1675 st->print("\n/proc/meminfo:\n");
1676 _print_ascii_file("/proc/meminfo", st);
1677 st->cr();
1678 }
1680 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1681 // but they're the same for all the bsd arch that we support
1682 // and they're the same for solaris but there's no common place to put this.
1683 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1684 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1685 "ILL_COPROC", "ILL_BADSTK" };
1687 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1688 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1689 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1691 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1693 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1695 void os::print_siginfo(outputStream* st, void* siginfo) {
1696 st->print("siginfo:");
1698 const int buflen = 100;
1699 char buf[buflen];
1700 siginfo_t *si = (siginfo_t*)siginfo;
1701 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1702 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1703 st->print("si_errno=%s", buf);
1704 } else {
1705 st->print("si_errno=%d", si->si_errno);
1706 }
1707 const int c = si->si_code;
1708 assert(c > 0, "unexpected si_code");
1709 switch (si->si_signo) {
1710 case SIGILL:
1711 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1712 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1713 break;
1714 case SIGFPE:
1715 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1716 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1717 break;
1718 case SIGSEGV:
1719 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1720 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1721 break;
1722 case SIGBUS:
1723 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1724 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1725 break;
1726 default:
1727 st->print(", si_code=%d", si->si_code);
1728 // no si_addr
1729 }
1731 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1732 UseSharedSpaces) {
1733 FileMapInfo* mapinfo = FileMapInfo::current_info();
1734 if (mapinfo->is_in_shared_space(si->si_addr)) {
1735 st->print("\n\nError accessing class data sharing archive." \
1736 " Mapped file inaccessible during execution, " \
1737 " possible disk/network problem.");
1738 }
1739 }
1740 st->cr();
1741 }
1744 static void print_signal_handler(outputStream* st, int sig,
1745 char* buf, size_t buflen);
1747 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1748 st->print_cr("Signal Handlers:");
1749 print_signal_handler(st, SIGSEGV, buf, buflen);
1750 print_signal_handler(st, SIGBUS , buf, buflen);
1751 print_signal_handler(st, SIGFPE , buf, buflen);
1752 print_signal_handler(st, SIGPIPE, buf, buflen);
1753 print_signal_handler(st, SIGXFSZ, buf, buflen);
1754 print_signal_handler(st, SIGILL , buf, buflen);
1755 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1756 print_signal_handler(st, SR_signum, buf, buflen);
1757 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1758 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1759 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1760 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1761 }
1763 static char saved_jvm_path[MAXPATHLEN] = {0};
1765 // Find the full path to the current module, libjvm
1766 void os::jvm_path(char *buf, jint buflen) {
1767 // Error checking.
1768 if (buflen < MAXPATHLEN) {
1769 assert(false, "must use a large-enough buffer");
1770 buf[0] = '\0';
1771 return;
1772 }
1773 // Lazy resolve the path to current module.
1774 if (saved_jvm_path[0] != 0) {
1775 strcpy(buf, saved_jvm_path);
1776 return;
1777 }
1779 char dli_fname[MAXPATHLEN];
1780 bool ret = dll_address_to_library_name(
1781 CAST_FROM_FN_PTR(address, os::jvm_path),
1782 dli_fname, sizeof(dli_fname), NULL);
1783 assert(ret, "cannot locate libjvm");
1784 char *rp = NULL;
1785 if (ret && dli_fname[0] != '\0') {
1786 rp = realpath(dli_fname, buf);
1787 }
1788 if (rp == NULL)
1789 return;
1791 if (Arguments::created_by_gamma_launcher()) {
1792 // Support for the gamma launcher. Typical value for buf is
1793 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1794 // the right place in the string, then assume we are installed in a JDK and
1795 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1796 // construct a path to the JVM being overridden.
1798 const char *p = buf + strlen(buf) - 1;
1799 for (int count = 0; p > buf && count < 5; ++count) {
1800 for (--p; p > buf && *p != '/'; --p)
1801 /* empty */ ;
1802 }
1804 if (strncmp(p, "/jre/lib/", 9) != 0) {
1805 // Look for JAVA_HOME in the environment.
1806 char* java_home_var = ::getenv("JAVA_HOME");
1807 if (java_home_var != NULL && java_home_var[0] != 0) {
1808 char* jrelib_p;
1809 int len;
1811 // Check the current module name "libjvm"
1812 p = strrchr(buf, '/');
1813 assert(strstr(p, "/libjvm") == p, "invalid library name");
1815 rp = realpath(java_home_var, buf);
1816 if (rp == NULL)
1817 return;
1819 // determine if this is a legacy image or modules image
1820 // modules image doesn't have "jre" subdirectory
1821 len = strlen(buf);
1822 jrelib_p = buf + len;
1824 // Add the appropriate library subdir
1825 snprintf(jrelib_p, buflen-len, "/jre/lib");
1826 if (0 != access(buf, F_OK)) {
1827 snprintf(jrelib_p, buflen-len, "/lib");
1828 }
1830 // Add the appropriate client or server subdir
1831 len = strlen(buf);
1832 jrelib_p = buf + len;
1833 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1834 if (0 != access(buf, F_OK)) {
1835 snprintf(jrelib_p, buflen-len, "");
1836 }
1838 // If the path exists within JAVA_HOME, add the JVM library name
1839 // to complete the path to JVM being overridden. Otherwise fallback
1840 // to the path to the current library.
1841 if (0 == access(buf, F_OK)) {
1842 // Use current module name "libjvm"
1843 len = strlen(buf);
1844 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1845 } else {
1846 // Fall back to path of current library
1847 rp = realpath(dli_fname, buf);
1848 if (rp == NULL)
1849 return;
1850 }
1851 }
1852 }
1853 }
1855 strcpy(saved_jvm_path, buf);
1856 }
1858 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1859 // no prefix required, not even "_"
1860 }
1862 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1863 // no suffix required
1864 }
1866 ////////////////////////////////////////////////////////////////////////////////
1867 // sun.misc.Signal support
1869 static volatile jint sigint_count = 0;
1871 static void
1872 UserHandler(int sig, void *siginfo, void *context) {
1873 // 4511530 - sem_post is serialized and handled by the manager thread. When
1874 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1875 // don't want to flood the manager thread with sem_post requests.
1876 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1877 return;
1879 // Ctrl-C is pressed during error reporting, likely because the error
1880 // handler fails to abort. Let VM die immediately.
1881 if (sig == SIGINT && is_error_reported()) {
1882 os::die();
1883 }
1885 os::signal_notify(sig);
1886 }
1888 void* os::user_handler() {
1889 return CAST_FROM_FN_PTR(void*, UserHandler);
1890 }
1892 extern "C" {
1893 typedef void (*sa_handler_t)(int);
1894 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1895 }
1897 void* os::signal(int signal_number, void* handler) {
1898 struct sigaction sigAct, oldSigAct;
1900 sigfillset(&(sigAct.sa_mask));
1901 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1902 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1904 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1905 // -1 means registration failed
1906 return (void *)-1;
1907 }
1909 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1910 }
1912 void os::signal_raise(int signal_number) {
1913 ::raise(signal_number);
1914 }
1916 /*
1917 * The following code is moved from os.cpp for making this
1918 * code platform specific, which it is by its very nature.
1919 */
1921 // Will be modified when max signal is changed to be dynamic
1922 int os::sigexitnum_pd() {
1923 return NSIG;
1924 }
1926 // a counter for each possible signal value
1927 static volatile jint pending_signals[NSIG+1] = { 0 };
1929 // Bsd(POSIX) specific hand shaking semaphore.
1930 #ifdef __APPLE__
1931 typedef semaphore_t os_semaphore_t;
1932 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1933 #define SEM_WAIT(sem) semaphore_wait(sem)
1934 #define SEM_POST(sem) semaphore_signal(sem)
1935 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1936 #else
1937 typedef sem_t os_semaphore_t;
1938 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1939 #define SEM_WAIT(sem) sem_wait(&sem)
1940 #define SEM_POST(sem) sem_post(&sem)
1941 #define SEM_DESTROY(sem) sem_destroy(&sem)
1942 #endif
1944 class Semaphore : public StackObj {
1945 public:
1946 Semaphore();
1947 ~Semaphore();
1948 void signal();
1949 void wait();
1950 bool trywait();
1951 bool timedwait(unsigned int sec, int nsec);
1952 private:
1953 jlong currenttime() const;
1954 os_semaphore_t _semaphore;
1955 };
1957 Semaphore::Semaphore() : _semaphore(0) {
1958 SEM_INIT(_semaphore, 0);
1959 }
1961 Semaphore::~Semaphore() {
1962 SEM_DESTROY(_semaphore);
1963 }
1965 void Semaphore::signal() {
1966 SEM_POST(_semaphore);
1967 }
1969 void Semaphore::wait() {
1970 SEM_WAIT(_semaphore);
1971 }
1973 jlong Semaphore::currenttime() const {
1974 struct timeval tv;
1975 gettimeofday(&tv, NULL);
1976 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1977 }
1979 #ifdef __APPLE__
1980 bool Semaphore::trywait() {
1981 return timedwait(0, 0);
1982 }
1984 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1985 kern_return_t kr = KERN_ABORTED;
1986 mach_timespec_t waitspec;
1987 waitspec.tv_sec = sec;
1988 waitspec.tv_nsec = nsec;
1990 jlong starttime = currenttime();
1992 kr = semaphore_timedwait(_semaphore, waitspec);
1993 while (kr == KERN_ABORTED) {
1994 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1996 jlong current = currenttime();
1997 jlong passedtime = current - starttime;
1999 if (passedtime >= totalwait) {
2000 waitspec.tv_sec = 0;
2001 waitspec.tv_nsec = 0;
2002 } else {
2003 jlong waittime = totalwait - (current - starttime);
2004 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2005 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2006 }
2008 kr = semaphore_timedwait(_semaphore, waitspec);
2009 }
2011 return kr == KERN_SUCCESS;
2012 }
2014 #else
2016 bool Semaphore::trywait() {
2017 return sem_trywait(&_semaphore) == 0;
2018 }
2020 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2021 struct timespec ts;
2022 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2024 while (1) {
2025 int result = sem_timedwait(&_semaphore, &ts);
2026 if (result == 0) {
2027 return true;
2028 } else if (errno == EINTR) {
2029 continue;
2030 } else if (errno == ETIMEDOUT) {
2031 return false;
2032 } else {
2033 return false;
2034 }
2035 }
2036 }
2038 #endif // __APPLE__
2040 static os_semaphore_t sig_sem;
2041 static Semaphore sr_semaphore;
2043 void os::signal_init_pd() {
2044 // Initialize signal structures
2045 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2047 // Initialize signal semaphore
2048 ::SEM_INIT(sig_sem, 0);
2049 }
2051 void os::signal_notify(int sig) {
2052 Atomic::inc(&pending_signals[sig]);
2053 ::SEM_POST(sig_sem);
2054 }
2056 static int check_pending_signals(bool wait) {
2057 Atomic::store(0, &sigint_count);
2058 for (;;) {
2059 for (int i = 0; i < NSIG + 1; i++) {
2060 jint n = pending_signals[i];
2061 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2062 return i;
2063 }
2064 }
2065 if (!wait) {
2066 return -1;
2067 }
2068 JavaThread *thread = JavaThread::current();
2069 ThreadBlockInVM tbivm(thread);
2071 bool threadIsSuspended;
2072 do {
2073 thread->set_suspend_equivalent();
2074 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2075 ::SEM_WAIT(sig_sem);
2077 // were we externally suspended while we were waiting?
2078 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2079 if (threadIsSuspended) {
2080 //
2081 // The semaphore has been incremented, but while we were waiting
2082 // another thread suspended us. We don't want to continue running
2083 // while suspended because that would surprise the thread that
2084 // suspended us.
2085 //
2086 ::SEM_POST(sig_sem);
2088 thread->java_suspend_self();
2089 }
2090 } while (threadIsSuspended);
2091 }
2092 }
2094 int os::signal_lookup() {
2095 return check_pending_signals(false);
2096 }
2098 int os::signal_wait() {
2099 return check_pending_signals(true);
2100 }
2102 ////////////////////////////////////////////////////////////////////////////////
2103 // Virtual Memory
2105 int os::vm_page_size() {
2106 // Seems redundant as all get out
2107 assert(os::Bsd::page_size() != -1, "must call os::init");
2108 return os::Bsd::page_size();
2109 }
2111 // Solaris allocates memory by pages.
2112 int os::vm_allocation_granularity() {
2113 assert(os::Bsd::page_size() != -1, "must call os::init");
2114 return os::Bsd::page_size();
2115 }
2117 // Rationale behind this function:
2118 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2119 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2120 // samples for JITted code. Here we create private executable mapping over the code cache
2121 // and then we can use standard (well, almost, as mapping can change) way to provide
2122 // info for the reporting script by storing timestamp and location of symbol
2123 void bsd_wrap_code(char* base, size_t size) {
2124 static volatile jint cnt = 0;
2126 if (!UseOprofile) {
2127 return;
2128 }
2130 char buf[PATH_MAX + 1];
2131 int num = Atomic::add(1, &cnt);
2133 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2134 os::get_temp_directory(), os::current_process_id(), num);
2135 unlink(buf);
2137 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2139 if (fd != -1) {
2140 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2141 if (rv != (off_t)-1) {
2142 if (::write(fd, "", 1) == 1) {
2143 mmap(base, size,
2144 PROT_READ|PROT_WRITE|PROT_EXEC,
2145 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2146 }
2147 }
2148 ::close(fd);
2149 unlink(buf);
2150 }
2151 }
2153 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2154 int err) {
2155 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2156 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2157 strerror(err), err);
2158 }
2160 // NOTE: Bsd kernel does not really reserve the pages for us.
2161 // All it does is to check if there are enough free pages
2162 // left at the time of mmap(). This could be a potential
2163 // problem.
2164 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2165 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2166 #ifdef __OpenBSD__
2167 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2168 if (::mprotect(addr, size, prot) == 0) {
2169 return true;
2170 }
2171 #else
2172 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2173 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2174 if (res != (uintptr_t) MAP_FAILED) {
2175 return true;
2176 }
2177 #endif
2179 // Warn about any commit errors we see in non-product builds just
2180 // in case mmap() doesn't work as described on the man page.
2181 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2183 return false;
2184 }
2186 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2187 bool exec) {
2188 // alignment_hint is ignored on this OS
2189 return pd_commit_memory(addr, size, exec);
2190 }
2192 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2193 const char* mesg) {
2194 assert(mesg != NULL, "mesg must be specified");
2195 if (!pd_commit_memory(addr, size, exec)) {
2196 // add extra info in product mode for vm_exit_out_of_memory():
2197 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2198 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2199 }
2200 }
2202 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2203 size_t alignment_hint, bool exec,
2204 const char* mesg) {
2205 // alignment_hint is ignored on this OS
2206 pd_commit_memory_or_exit(addr, size, exec, mesg);
2207 }
2209 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2210 }
2212 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2213 ::madvise(addr, bytes, MADV_DONTNEED);
2214 }
2216 void os::numa_make_global(char *addr, size_t bytes) {
2217 }
2219 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2220 }
2222 bool os::numa_topology_changed() { return false; }
2224 size_t os::numa_get_groups_num() {
2225 return 1;
2226 }
2228 int os::numa_get_group_id() {
2229 return 0;
2230 }
2232 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2233 if (size > 0) {
2234 ids[0] = 0;
2235 return 1;
2236 }
2237 return 0;
2238 }
2240 bool os::get_page_info(char *start, page_info* info) {
2241 return false;
2242 }
2244 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2245 return end;
2246 }
2249 bool os::pd_uncommit_memory(char* addr, size_t size) {
2250 #ifdef __OpenBSD__
2251 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2252 return ::mprotect(addr, size, PROT_NONE) == 0;
2253 #else
2254 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2255 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2256 return res != (uintptr_t) MAP_FAILED;
2257 #endif
2258 }
2260 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2261 return os::commit_memory(addr, size, !ExecMem);
2262 }
2264 // If this is a growable mapping, remove the guard pages entirely by
2265 // munmap()ping them. If not, just call uncommit_memory().
2266 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2267 return os::uncommit_memory(addr, size);
2268 }
2270 static address _highest_vm_reserved_address = NULL;
2272 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2273 // at 'requested_addr'. If there are existing memory mappings at the same
2274 // location, however, they will be overwritten. If 'fixed' is false,
2275 // 'requested_addr' is only treated as a hint, the return value may or
2276 // may not start from the requested address. Unlike Bsd mmap(), this
2277 // function returns NULL to indicate failure.
2278 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2279 char * addr;
2280 int flags;
2282 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2283 if (fixed) {
2284 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2285 flags |= MAP_FIXED;
2286 }
2288 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2289 // touch an uncommitted page. Otherwise, the read/write might
2290 // succeed if we have enough swap space to back the physical page.
2291 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2292 flags, -1, 0);
2294 if (addr != MAP_FAILED) {
2295 // anon_mmap() should only get called during VM initialization,
2296 // don't need lock (actually we can skip locking even it can be called
2297 // from multiple threads, because _highest_vm_reserved_address is just a
2298 // hint about the upper limit of non-stack memory regions.)
2299 if ((address)addr + bytes > _highest_vm_reserved_address) {
2300 _highest_vm_reserved_address = (address)addr + bytes;
2301 }
2302 }
2304 return addr == MAP_FAILED ? NULL : addr;
2305 }
2307 // Don't update _highest_vm_reserved_address, because there might be memory
2308 // regions above addr + size. If so, releasing a memory region only creates
2309 // a hole in the address space, it doesn't help prevent heap-stack collision.
2310 //
2311 static int anon_munmap(char * addr, size_t size) {
2312 return ::munmap(addr, size) == 0;
2313 }
2315 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2316 size_t alignment_hint) {
2317 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2318 }
2320 bool os::pd_release_memory(char* addr, size_t size) {
2321 return anon_munmap(addr, size);
2322 }
2324 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2325 // Bsd wants the mprotect address argument to be page aligned.
2326 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2328 // According to SUSv3, mprotect() should only be used with mappings
2329 // established by mmap(), and mmap() always maps whole pages. Unaligned
2330 // 'addr' likely indicates problem in the VM (e.g. trying to change
2331 // protection of malloc'ed or statically allocated memory). Check the
2332 // caller if you hit this assert.
2333 assert(addr == bottom, "sanity check");
2335 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2336 return ::mprotect(bottom, size, prot) == 0;
2337 }
2339 // Set protections specified
2340 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2341 bool is_committed) {
2342 unsigned int p = 0;
2343 switch (prot) {
2344 case MEM_PROT_NONE: p = PROT_NONE; break;
2345 case MEM_PROT_READ: p = PROT_READ; break;
2346 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2347 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2348 default:
2349 ShouldNotReachHere();
2350 }
2351 // is_committed is unused.
2352 return bsd_mprotect(addr, bytes, p);
2353 }
2355 bool os::guard_memory(char* addr, size_t size) {
2356 return bsd_mprotect(addr, size, PROT_NONE);
2357 }
2359 bool os::unguard_memory(char* addr, size_t size) {
2360 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2361 }
2363 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2364 return false;
2365 }
2367 // Large page support
2369 static size_t _large_page_size = 0;
2371 void os::large_page_init() {
2372 }
2375 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2376 fatal("This code is not used or maintained.");
2378 // "exec" is passed in but not used. Creating the shared image for
2379 // the code cache doesn't have an SHM_X executable permission to check.
2380 assert(UseLargePages && UseSHM, "only for SHM large pages");
2382 key_t key = IPC_PRIVATE;
2383 char *addr;
2385 bool warn_on_failure = UseLargePages &&
2386 (!FLAG_IS_DEFAULT(UseLargePages) ||
2387 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2388 );
2389 char msg[128];
2391 // Create a large shared memory region to attach to based on size.
2392 // Currently, size is the total size of the heap
2393 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2394 if (shmid == -1) {
2395 // Possible reasons for shmget failure:
2396 // 1. shmmax is too small for Java heap.
2397 // > check shmmax value: cat /proc/sys/kernel/shmmax
2398 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2399 // 2. not enough large page memory.
2400 // > check available large pages: cat /proc/meminfo
2401 // > increase amount of large pages:
2402 // echo new_value > /proc/sys/vm/nr_hugepages
2403 // Note 1: different Bsd may use different name for this property,
2404 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2405 // Note 2: it's possible there's enough physical memory available but
2406 // they are so fragmented after a long run that they can't
2407 // coalesce into large pages. Try to reserve large pages when
2408 // the system is still "fresh".
2409 if (warn_on_failure) {
2410 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2411 warning(msg);
2412 }
2413 return NULL;
2414 }
2416 // attach to the region
2417 addr = (char*)shmat(shmid, req_addr, 0);
2418 int err = errno;
2420 // Remove shmid. If shmat() is successful, the actual shared memory segment
2421 // will be deleted when it's detached by shmdt() or when the process
2422 // terminates. If shmat() is not successful this will remove the shared
2423 // segment immediately.
2424 shmctl(shmid, IPC_RMID, NULL);
2426 if ((intptr_t)addr == -1) {
2427 if (warn_on_failure) {
2428 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2429 warning(msg);
2430 }
2431 return NULL;
2432 }
2434 // The memory is committed
2435 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2437 return addr;
2438 }
2440 bool os::release_memory_special(char* base, size_t bytes) {
2441 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2442 // detaching the SHM segment will also delete it, see reserve_memory_special()
2443 int rslt = shmdt(base);
2444 if (rslt == 0) {
2445 tkr.record((address)base, bytes);
2446 return true;
2447 } else {
2448 tkr.discard();
2449 return false;
2450 }
2452 }
2454 size_t os::large_page_size() {
2455 return _large_page_size;
2456 }
2458 // HugeTLBFS allows application to commit large page memory on demand;
2459 // with SysV SHM the entire memory region must be allocated as shared
2460 // memory.
2461 bool os::can_commit_large_page_memory() {
2462 return UseHugeTLBFS;
2463 }
2465 bool os::can_execute_large_page_memory() {
2466 return UseHugeTLBFS;
2467 }
2469 // Reserve memory at an arbitrary address, only if that area is
2470 // available (and not reserved for something else).
2472 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2473 const int max_tries = 10;
2474 char* base[max_tries];
2475 size_t size[max_tries];
2476 const size_t gap = 0x000000;
2478 // Assert only that the size is a multiple of the page size, since
2479 // that's all that mmap requires, and since that's all we really know
2480 // about at this low abstraction level. If we need higher alignment,
2481 // we can either pass an alignment to this method or verify alignment
2482 // in one of the methods further up the call chain. See bug 5044738.
2483 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2485 // Repeatedly allocate blocks until the block is allocated at the
2486 // right spot. Give up after max_tries. Note that reserve_memory() will
2487 // automatically update _highest_vm_reserved_address if the call is
2488 // successful. The variable tracks the highest memory address every reserved
2489 // by JVM. It is used to detect heap-stack collision if running with
2490 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2491 // space than needed, it could confuse the collision detecting code. To
2492 // solve the problem, save current _highest_vm_reserved_address and
2493 // calculate the correct value before return.
2494 address old_highest = _highest_vm_reserved_address;
2496 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2497 // if kernel honors the hint then we can return immediately.
2498 char * addr = anon_mmap(requested_addr, bytes, false);
2499 if (addr == requested_addr) {
2500 return requested_addr;
2501 }
2503 if (addr != NULL) {
2504 // mmap() is successful but it fails to reserve at the requested address
2505 anon_munmap(addr, bytes);
2506 }
2508 int i;
2509 for (i = 0; i < max_tries; ++i) {
2510 base[i] = reserve_memory(bytes);
2512 if (base[i] != NULL) {
2513 // Is this the block we wanted?
2514 if (base[i] == requested_addr) {
2515 size[i] = bytes;
2516 break;
2517 }
2519 // Does this overlap the block we wanted? Give back the overlapped
2520 // parts and try again.
2522 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2523 if (top_overlap >= 0 && top_overlap < bytes) {
2524 unmap_memory(base[i], top_overlap);
2525 base[i] += top_overlap;
2526 size[i] = bytes - top_overlap;
2527 } else {
2528 size_t bottom_overlap = base[i] + bytes - requested_addr;
2529 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2530 unmap_memory(requested_addr, bottom_overlap);
2531 size[i] = bytes - bottom_overlap;
2532 } else {
2533 size[i] = bytes;
2534 }
2535 }
2536 }
2537 }
2539 // Give back the unused reserved pieces.
2541 for (int j = 0; j < i; ++j) {
2542 if (base[j] != NULL) {
2543 unmap_memory(base[j], size[j]);
2544 }
2545 }
2547 if (i < max_tries) {
2548 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2549 return requested_addr;
2550 } else {
2551 _highest_vm_reserved_address = old_highest;
2552 return NULL;
2553 }
2554 }
2556 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2557 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2558 }
2560 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2561 // Solaris uses poll(), bsd uses park().
2562 // Poll() is likely a better choice, assuming that Thread.interrupt()
2563 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2564 // SIGSEGV, see 4355769.
2566 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2567 assert(thread == Thread::current(), "thread consistency check");
2569 ParkEvent * const slp = thread->_SleepEvent ;
2570 slp->reset() ;
2571 OrderAccess::fence() ;
2573 if (interruptible) {
2574 jlong prevtime = javaTimeNanos();
2576 for (;;) {
2577 if (os::is_interrupted(thread, true)) {
2578 return OS_INTRPT;
2579 }
2581 jlong newtime = javaTimeNanos();
2583 if (newtime - prevtime < 0) {
2584 // time moving backwards, should only happen if no monotonic clock
2585 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2586 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2587 } else {
2588 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2589 }
2591 if(millis <= 0) {
2592 return OS_OK;
2593 }
2595 prevtime = newtime;
2597 {
2598 assert(thread->is_Java_thread(), "sanity check");
2599 JavaThread *jt = (JavaThread *) thread;
2600 ThreadBlockInVM tbivm(jt);
2601 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2603 jt->set_suspend_equivalent();
2604 // cleared by handle_special_suspend_equivalent_condition() or
2605 // java_suspend_self() via check_and_wait_while_suspended()
2607 slp->park(millis);
2609 // were we externally suspended while we were waiting?
2610 jt->check_and_wait_while_suspended();
2611 }
2612 }
2613 } else {
2614 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2615 jlong prevtime = javaTimeNanos();
2617 for (;;) {
2618 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2619 // the 1st iteration ...
2620 jlong newtime = javaTimeNanos();
2622 if (newtime - prevtime < 0) {
2623 // time moving backwards, should only happen if no monotonic clock
2624 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2625 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2626 } else {
2627 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2628 }
2630 if(millis <= 0) break ;
2632 prevtime = newtime;
2633 slp->park(millis);
2634 }
2635 return OS_OK ;
2636 }
2637 }
2639 void os::naked_short_sleep(jlong ms) {
2640 struct timespec req;
2642 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2643 req.tv_sec = 0;
2644 if (ms > 0) {
2645 req.tv_nsec = (ms % 1000) * 1000000;
2646 }
2647 else {
2648 req.tv_nsec = 1;
2649 }
2651 nanosleep(&req, NULL);
2653 return;
2654 }
2656 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2657 void os::infinite_sleep() {
2658 while (true) { // sleep forever ...
2659 ::sleep(100); // ... 100 seconds at a time
2660 }
2661 }
2663 // Used to convert frequent JVM_Yield() to nops
2664 bool os::dont_yield() {
2665 return DontYieldALot;
2666 }
2668 void os::yield() {
2669 sched_yield();
2670 }
2672 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2674 void os::yield_all(int attempts) {
2675 // Yields to all threads, including threads with lower priorities
2676 // Threads on Bsd are all with same priority. The Solaris style
2677 // os::yield_all() with nanosleep(1ms) is not necessary.
2678 sched_yield();
2679 }
2681 // Called from the tight loops to possibly influence time-sharing heuristics
2682 void os::loop_breaker(int attempts) {
2683 os::yield_all(attempts);
2684 }
2686 ////////////////////////////////////////////////////////////////////////////////
2687 // thread priority support
2689 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2690 // only supports dynamic priority, static priority must be zero. For real-time
2691 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2692 // However, for large multi-threaded applications, SCHED_RR is not only slower
2693 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2694 // of 5 runs - Sep 2005).
2695 //
2696 // The following code actually changes the niceness of kernel-thread/LWP. It
2697 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2698 // not the entire user process, and user level threads are 1:1 mapped to kernel
2699 // threads. It has always been the case, but could change in the future. For
2700 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2701 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2703 #if !defined(__APPLE__)
2704 int os::java_to_os_priority[CriticalPriority + 1] = {
2705 19, // 0 Entry should never be used
2707 0, // 1 MinPriority
2708 3, // 2
2709 6, // 3
2711 10, // 4
2712 15, // 5 NormPriority
2713 18, // 6
2715 21, // 7
2716 25, // 8
2717 28, // 9 NearMaxPriority
2719 31, // 10 MaxPriority
2721 31 // 11 CriticalPriority
2722 };
2723 #else
2724 /* Using Mach high-level priority assignments */
2725 int os::java_to_os_priority[CriticalPriority + 1] = {
2726 0, // 0 Entry should never be used (MINPRI_USER)
2728 27, // 1 MinPriority
2729 28, // 2
2730 29, // 3
2732 30, // 4
2733 31, // 5 NormPriority (BASEPRI_DEFAULT)
2734 32, // 6
2736 33, // 7
2737 34, // 8
2738 35, // 9 NearMaxPriority
2740 36, // 10 MaxPriority
2742 36 // 11 CriticalPriority
2743 };
2744 #endif
2746 static int prio_init() {
2747 if (ThreadPriorityPolicy == 1) {
2748 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2749 // if effective uid is not root. Perhaps, a more elegant way of doing
2750 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2751 if (geteuid() != 0) {
2752 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2753 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2754 }
2755 ThreadPriorityPolicy = 0;
2756 }
2757 }
2758 if (UseCriticalJavaThreadPriority) {
2759 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2760 }
2761 return 0;
2762 }
2764 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2765 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2767 #ifdef __OpenBSD__
2768 // OpenBSD pthread_setprio starves low priority threads
2769 return OS_OK;
2770 #elif defined(__FreeBSD__)
2771 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2772 #elif defined(__APPLE__) || defined(__NetBSD__)
2773 struct sched_param sp;
2774 int policy;
2775 pthread_t self = pthread_self();
2777 if (pthread_getschedparam(self, &policy, &sp) != 0)
2778 return OS_ERR;
2780 sp.sched_priority = newpri;
2781 if (pthread_setschedparam(self, policy, &sp) != 0)
2782 return OS_ERR;
2784 return OS_OK;
2785 #else
2786 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2787 return (ret == 0) ? OS_OK : OS_ERR;
2788 #endif
2789 }
2791 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2792 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2793 *priority_ptr = java_to_os_priority[NormPriority];
2794 return OS_OK;
2795 }
2797 errno = 0;
2798 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2799 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2800 #elif defined(__APPLE__) || defined(__NetBSD__)
2801 int policy;
2802 struct sched_param sp;
2804 pthread_getschedparam(pthread_self(), &policy, &sp);
2805 *priority_ptr = sp.sched_priority;
2806 #else
2807 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2808 #endif
2809 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2810 }
2812 // Hint to the underlying OS that a task switch would not be good.
2813 // Void return because it's a hint and can fail.
2814 void os::hint_no_preempt() {}
2816 ////////////////////////////////////////////////////////////////////////////////
2817 // suspend/resume support
2819 // the low-level signal-based suspend/resume support is a remnant from the
2820 // old VM-suspension that used to be for java-suspension, safepoints etc,
2821 // within hotspot. Now there is a single use-case for this:
2822 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2823 // that runs in the watcher thread.
2824 // The remaining code is greatly simplified from the more general suspension
2825 // code that used to be used.
2826 //
2827 // The protocol is quite simple:
2828 // - suspend:
2829 // - sends a signal to the target thread
2830 // - polls the suspend state of the osthread using a yield loop
2831 // - target thread signal handler (SR_handler) sets suspend state
2832 // and blocks in sigsuspend until continued
2833 // - resume:
2834 // - sets target osthread state to continue
2835 // - sends signal to end the sigsuspend loop in the SR_handler
2836 //
2837 // Note that the SR_lock plays no role in this suspend/resume protocol.
2838 //
2840 static void resume_clear_context(OSThread *osthread) {
2841 osthread->set_ucontext(NULL);
2842 osthread->set_siginfo(NULL);
2843 }
2845 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2846 osthread->set_ucontext(context);
2847 osthread->set_siginfo(siginfo);
2848 }
2850 //
2851 // Handler function invoked when a thread's execution is suspended or
2852 // resumed. We have to be careful that only async-safe functions are
2853 // called here (Note: most pthread functions are not async safe and
2854 // should be avoided.)
2855 //
2856 // Note: sigwait() is a more natural fit than sigsuspend() from an
2857 // interface point of view, but sigwait() prevents the signal hander
2858 // from being run. libpthread would get very confused by not having
2859 // its signal handlers run and prevents sigwait()'s use with the
2860 // mutex granting granting signal.
2861 //
2862 // Currently only ever called on the VMThread or JavaThread
2863 //
2864 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2865 // Save and restore errno to avoid confusing native code with EINTR
2866 // after sigsuspend.
2867 int old_errno = errno;
2869 Thread* thread = Thread::current();
2870 OSThread* osthread = thread->osthread();
2871 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2873 os::SuspendResume::State current = osthread->sr.state();
2874 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2875 suspend_save_context(osthread, siginfo, context);
2877 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2878 os::SuspendResume::State state = osthread->sr.suspended();
2879 if (state == os::SuspendResume::SR_SUSPENDED) {
2880 sigset_t suspend_set; // signals for sigsuspend()
2882 // get current set of blocked signals and unblock resume signal
2883 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2884 sigdelset(&suspend_set, SR_signum);
2886 sr_semaphore.signal();
2887 // wait here until we are resumed
2888 while (1) {
2889 sigsuspend(&suspend_set);
2891 os::SuspendResume::State result = osthread->sr.running();
2892 if (result == os::SuspendResume::SR_RUNNING) {
2893 sr_semaphore.signal();
2894 break;
2895 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2896 ShouldNotReachHere();
2897 }
2898 }
2900 } else if (state == os::SuspendResume::SR_RUNNING) {
2901 // request was cancelled, continue
2902 } else {
2903 ShouldNotReachHere();
2904 }
2906 resume_clear_context(osthread);
2907 } else if (current == os::SuspendResume::SR_RUNNING) {
2908 // request was cancelled, continue
2909 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2910 // ignore
2911 } else {
2912 // ignore
2913 }
2915 errno = old_errno;
2916 }
2919 static int SR_initialize() {
2920 struct sigaction act;
2921 char *s;
2922 /* Get signal number to use for suspend/resume */
2923 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2924 int sig = ::strtol(s, 0, 10);
2925 if (sig > 0 || sig < NSIG) {
2926 SR_signum = sig;
2927 }
2928 }
2930 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2931 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2933 sigemptyset(&SR_sigset);
2934 sigaddset(&SR_sigset, SR_signum);
2936 /* Set up signal handler for suspend/resume */
2937 act.sa_flags = SA_RESTART|SA_SIGINFO;
2938 act.sa_handler = (void (*)(int)) SR_handler;
2940 // SR_signum is blocked by default.
2941 // 4528190 - We also need to block pthread restart signal (32 on all
2942 // supported Bsd platforms). Note that BsdThreads need to block
2943 // this signal for all threads to work properly. So we don't have
2944 // to use hard-coded signal number when setting up the mask.
2945 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2947 if (sigaction(SR_signum, &act, 0) == -1) {
2948 return -1;
2949 }
2951 // Save signal flag
2952 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2953 return 0;
2954 }
2956 static int sr_notify(OSThread* osthread) {
2957 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2958 assert_status(status == 0, status, "pthread_kill");
2959 return status;
2960 }
2962 // "Randomly" selected value for how long we want to spin
2963 // before bailing out on suspending a thread, also how often
2964 // we send a signal to a thread we want to resume
2965 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2966 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2968 // returns true on success and false on error - really an error is fatal
2969 // but this seems the normal response to library errors
2970 static bool do_suspend(OSThread* osthread) {
2971 assert(osthread->sr.is_running(), "thread should be running");
2972 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2974 // mark as suspended and send signal
2975 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2976 // failed to switch, state wasn't running?
2977 ShouldNotReachHere();
2978 return false;
2979 }
2981 if (sr_notify(osthread) != 0) {
2982 ShouldNotReachHere();
2983 }
2985 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2986 while (true) {
2987 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2988 break;
2989 } else {
2990 // timeout
2991 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2992 if (cancelled == os::SuspendResume::SR_RUNNING) {
2993 return false;
2994 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2995 // make sure that we consume the signal on the semaphore as well
2996 sr_semaphore.wait();
2997 break;
2998 } else {
2999 ShouldNotReachHere();
3000 return false;
3001 }
3002 }
3003 }
3005 guarantee(osthread->sr.is_suspended(), "Must be suspended");
3006 return true;
3007 }
3009 static void do_resume(OSThread* osthread) {
3010 assert(osthread->sr.is_suspended(), "thread should be suspended");
3011 assert(!sr_semaphore.trywait(), "invalid semaphore state");
3013 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
3014 // failed to switch to WAKEUP_REQUEST
3015 ShouldNotReachHere();
3016 return;
3017 }
3019 while (true) {
3020 if (sr_notify(osthread) == 0) {
3021 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3022 if (osthread->sr.is_running()) {
3023 return;
3024 }
3025 }
3026 } else {
3027 ShouldNotReachHere();
3028 }
3029 }
3031 guarantee(osthread->sr.is_running(), "Must be running!");
3032 }
3034 ////////////////////////////////////////////////////////////////////////////////
3035 // interrupt support
3037 void os::interrupt(Thread* thread) {
3038 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3039 "possibility of dangling Thread pointer");
3041 OSThread* osthread = thread->osthread();
3043 if (!osthread->interrupted()) {
3044 osthread->set_interrupted(true);
3045 // More than one thread can get here with the same value of osthread,
3046 // resulting in multiple notifications. We do, however, want the store
3047 // to interrupted() to be visible to other threads before we execute unpark().
3048 OrderAccess::fence();
3049 ParkEvent * const slp = thread->_SleepEvent ;
3050 if (slp != NULL) slp->unpark() ;
3051 }
3053 // For JSR166. Unpark even if interrupt status already was set
3054 if (thread->is_Java_thread())
3055 ((JavaThread*)thread)->parker()->unpark();
3057 ParkEvent * ev = thread->_ParkEvent ;
3058 if (ev != NULL) ev->unpark() ;
3060 }
3062 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3063 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3064 "possibility of dangling Thread pointer");
3066 OSThread* osthread = thread->osthread();
3068 bool interrupted = osthread->interrupted();
3070 if (interrupted && clear_interrupted) {
3071 osthread->set_interrupted(false);
3072 // consider thread->_SleepEvent->reset() ... optional optimization
3073 }
3075 return interrupted;
3076 }
3078 ///////////////////////////////////////////////////////////////////////////////////
3079 // signal handling (except suspend/resume)
3081 // This routine may be used by user applications as a "hook" to catch signals.
3082 // The user-defined signal handler must pass unrecognized signals to this
3083 // routine, and if it returns true (non-zero), then the signal handler must
3084 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3085 // routine will never retun false (zero), but instead will execute a VM panic
3086 // routine kill the process.
3087 //
3088 // If this routine returns false, it is OK to call it again. This allows
3089 // the user-defined signal handler to perform checks either before or after
3090 // the VM performs its own checks. Naturally, the user code would be making
3091 // a serious error if it tried to handle an exception (such as a null check
3092 // or breakpoint) that the VM was generating for its own correct operation.
3093 //
3094 // This routine may recognize any of the following kinds of signals:
3095 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3096 // It should be consulted by handlers for any of those signals.
3097 //
3098 // The caller of this routine must pass in the three arguments supplied
3099 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3100 // field of the structure passed to sigaction(). This routine assumes that
3101 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3102 //
3103 // Note that the VM will print warnings if it detects conflicting signal
3104 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3105 //
3106 extern "C" JNIEXPORT int
3107 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3108 void* ucontext, int abort_if_unrecognized);
3110 void signalHandler(int sig, siginfo_t* info, void* uc) {
3111 assert(info != NULL && uc != NULL, "it must be old kernel");
3112 int orig_errno = errno; // Preserve errno value over signal handler.
3113 JVM_handle_bsd_signal(sig, info, uc, true);
3114 errno = orig_errno;
3115 }
3118 // This boolean allows users to forward their own non-matching signals
3119 // to JVM_handle_bsd_signal, harmlessly.
3120 bool os::Bsd::signal_handlers_are_installed = false;
3122 // For signal-chaining
3123 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3124 unsigned int os::Bsd::sigs = 0;
3125 bool os::Bsd::libjsig_is_loaded = false;
3126 typedef struct sigaction *(*get_signal_t)(int);
3127 get_signal_t os::Bsd::get_signal_action = NULL;
3129 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3130 struct sigaction *actp = NULL;
3132 if (libjsig_is_loaded) {
3133 // Retrieve the old signal handler from libjsig
3134 actp = (*get_signal_action)(sig);
3135 }
3136 if (actp == NULL) {
3137 // Retrieve the preinstalled signal handler from jvm
3138 actp = get_preinstalled_handler(sig);
3139 }
3141 return actp;
3142 }
3144 static bool call_chained_handler(struct sigaction *actp, int sig,
3145 siginfo_t *siginfo, void *context) {
3146 // Call the old signal handler
3147 if (actp->sa_handler == SIG_DFL) {
3148 // It's more reasonable to let jvm treat it as an unexpected exception
3149 // instead of taking the default action.
3150 return false;
3151 } else if (actp->sa_handler != SIG_IGN) {
3152 if ((actp->sa_flags & SA_NODEFER) == 0) {
3153 // automaticlly block the signal
3154 sigaddset(&(actp->sa_mask), sig);
3155 }
3157 sa_handler_t hand;
3158 sa_sigaction_t sa;
3159 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3160 // retrieve the chained handler
3161 if (siginfo_flag_set) {
3162 sa = actp->sa_sigaction;
3163 } else {
3164 hand = actp->sa_handler;
3165 }
3167 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3168 actp->sa_handler = SIG_DFL;
3169 }
3171 // try to honor the signal mask
3172 sigset_t oset;
3173 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3175 // call into the chained handler
3176 if (siginfo_flag_set) {
3177 (*sa)(sig, siginfo, context);
3178 } else {
3179 (*hand)(sig);
3180 }
3182 // restore the signal mask
3183 pthread_sigmask(SIG_SETMASK, &oset, 0);
3184 }
3185 // Tell jvm's signal handler the signal is taken care of.
3186 return true;
3187 }
3189 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3190 bool chained = false;
3191 // signal-chaining
3192 if (UseSignalChaining) {
3193 struct sigaction *actp = get_chained_signal_action(sig);
3194 if (actp != NULL) {
3195 chained = call_chained_handler(actp, sig, siginfo, context);
3196 }
3197 }
3198 return chained;
3199 }
3201 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3202 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3203 return &sigact[sig];
3204 }
3205 return NULL;
3206 }
3208 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3209 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3210 sigact[sig] = oldAct;
3211 sigs |= (unsigned int)1 << sig;
3212 }
3214 // for diagnostic
3215 int os::Bsd::sigflags[MAXSIGNUM];
3217 int os::Bsd::get_our_sigflags(int sig) {
3218 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3219 return sigflags[sig];
3220 }
3222 void os::Bsd::set_our_sigflags(int sig, int flags) {
3223 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3224 sigflags[sig] = flags;
3225 }
3227 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3228 // Check for overwrite.
3229 struct sigaction oldAct;
3230 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3232 void* oldhand = oldAct.sa_sigaction
3233 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3234 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3235 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3236 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3237 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3238 if (AllowUserSignalHandlers || !set_installed) {
3239 // Do not overwrite; user takes responsibility to forward to us.
3240 return;
3241 } else if (UseSignalChaining) {
3242 // save the old handler in jvm
3243 save_preinstalled_handler(sig, oldAct);
3244 // libjsig also interposes the sigaction() call below and saves the
3245 // old sigaction on it own.
3246 } else {
3247 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3248 "%#lx for signal %d.", (long)oldhand, sig));
3249 }
3250 }
3252 struct sigaction sigAct;
3253 sigfillset(&(sigAct.sa_mask));
3254 sigAct.sa_handler = SIG_DFL;
3255 if (!set_installed) {
3256 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3257 } else {
3258 sigAct.sa_sigaction = signalHandler;
3259 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3260 }
3261 #if __APPLE__
3262 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3263 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3264 // if the signal handler declares it will handle it on alternate stack.
3265 // Notice we only declare we will handle it on alt stack, but we are not
3266 // actually going to use real alt stack - this is just a workaround.
3267 // Please see ux_exception.c, method catch_mach_exception_raise for details
3268 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3269 if (sig == SIGSEGV) {
3270 sigAct.sa_flags |= SA_ONSTACK;
3271 }
3272 #endif
3274 // Save flags, which are set by ours
3275 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3276 sigflags[sig] = sigAct.sa_flags;
3278 int ret = sigaction(sig, &sigAct, &oldAct);
3279 assert(ret == 0, "check");
3281 void* oldhand2 = oldAct.sa_sigaction
3282 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3283 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3284 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3285 }
3287 // install signal handlers for signals that HotSpot needs to
3288 // handle in order to support Java-level exception handling.
3290 void os::Bsd::install_signal_handlers() {
3291 if (!signal_handlers_are_installed) {
3292 signal_handlers_are_installed = true;
3294 // signal-chaining
3295 typedef void (*signal_setting_t)();
3296 signal_setting_t begin_signal_setting = NULL;
3297 signal_setting_t end_signal_setting = NULL;
3298 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3299 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3300 if (begin_signal_setting != NULL) {
3301 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3302 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3303 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3304 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3305 libjsig_is_loaded = true;
3306 assert(UseSignalChaining, "should enable signal-chaining");
3307 }
3308 if (libjsig_is_loaded) {
3309 // Tell libjsig jvm is setting signal handlers
3310 (*begin_signal_setting)();
3311 }
3313 set_signal_handler(SIGSEGV, true);
3314 set_signal_handler(SIGPIPE, true);
3315 set_signal_handler(SIGBUS, true);
3316 set_signal_handler(SIGILL, true);
3317 set_signal_handler(SIGFPE, true);
3318 set_signal_handler(SIGXFSZ, true);
3320 #if defined(__APPLE__)
3321 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3322 // signals caught and handled by the JVM. To work around this, we reset the mach task
3323 // signal handler that's placed on our process by CrashReporter. This disables
3324 // CrashReporter-based reporting.
3325 //
3326 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3327 // on caught fatal signals.
3328 //
3329 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3330 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3331 // exception handling, while leaving the standard BSD signal handlers functional.
3332 kern_return_t kr;
3333 kr = task_set_exception_ports(mach_task_self(),
3334 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3335 MACH_PORT_NULL,
3336 EXCEPTION_STATE_IDENTITY,
3337 MACHINE_THREAD_STATE);
3339 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3340 #endif
3342 if (libjsig_is_loaded) {
3343 // Tell libjsig jvm finishes setting signal handlers
3344 (*end_signal_setting)();
3345 }
3347 // We don't activate signal checker if libjsig is in place, we trust ourselves
3348 // and if UserSignalHandler is installed all bets are off
3349 if (CheckJNICalls) {
3350 if (libjsig_is_loaded) {
3351 if (PrintJNIResolving) {
3352 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3353 }
3354 check_signals = false;
3355 }
3356 if (AllowUserSignalHandlers) {
3357 if (PrintJNIResolving) {
3358 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3359 }
3360 check_signals = false;
3361 }
3362 }
3363 }
3364 }
3367 /////
3368 // glibc on Bsd platform uses non-documented flag
3369 // to indicate, that some special sort of signal
3370 // trampoline is used.
3371 // We will never set this flag, and we should
3372 // ignore this flag in our diagnostic
3373 #ifdef SIGNIFICANT_SIGNAL_MASK
3374 #undef SIGNIFICANT_SIGNAL_MASK
3375 #endif
3376 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3378 static const char* get_signal_handler_name(address handler,
3379 char* buf, int buflen) {
3380 int offset;
3381 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3382 if (found) {
3383 // skip directory names
3384 const char *p1, *p2;
3385 p1 = buf;
3386 size_t len = strlen(os::file_separator());
3387 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3388 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3389 } else {
3390 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3391 }
3392 return buf;
3393 }
3395 static void print_signal_handler(outputStream* st, int sig,
3396 char* buf, size_t buflen) {
3397 struct sigaction sa;
3399 sigaction(sig, NULL, &sa);
3401 // See comment for SIGNIFICANT_SIGNAL_MASK define
3402 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3404 st->print("%s: ", os::exception_name(sig, buf, buflen));
3406 address handler = (sa.sa_flags & SA_SIGINFO)
3407 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3408 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3410 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3411 st->print("SIG_DFL");
3412 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3413 st->print("SIG_IGN");
3414 } else {
3415 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3416 }
3418 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3420 address rh = VMError::get_resetted_sighandler(sig);
3421 // May be, handler was resetted by VMError?
3422 if(rh != NULL) {
3423 handler = rh;
3424 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3425 }
3427 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3429 // Check: is it our handler?
3430 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3431 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3432 // It is our signal handler
3433 // check for flags, reset system-used one!
3434 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3435 st->print(
3436 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3437 os::Bsd::get_our_sigflags(sig));
3438 }
3439 }
3440 st->cr();
3441 }
3444 #define DO_SIGNAL_CHECK(sig) \
3445 if (!sigismember(&check_signal_done, sig)) \
3446 os::Bsd::check_signal_handler(sig)
3448 // This method is a periodic task to check for misbehaving JNI applications
3449 // under CheckJNI, we can add any periodic checks here
3451 void os::run_periodic_checks() {
3453 if (check_signals == false) return;
3455 // SEGV and BUS if overridden could potentially prevent
3456 // generation of hs*.log in the event of a crash, debugging
3457 // such a case can be very challenging, so we absolutely
3458 // check the following for a good measure:
3459 DO_SIGNAL_CHECK(SIGSEGV);
3460 DO_SIGNAL_CHECK(SIGILL);
3461 DO_SIGNAL_CHECK(SIGFPE);
3462 DO_SIGNAL_CHECK(SIGBUS);
3463 DO_SIGNAL_CHECK(SIGPIPE);
3464 DO_SIGNAL_CHECK(SIGXFSZ);
3467 // ReduceSignalUsage allows the user to override these handlers
3468 // see comments at the very top and jvm_solaris.h
3469 if (!ReduceSignalUsage) {
3470 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3471 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3472 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3473 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3474 }
3476 DO_SIGNAL_CHECK(SR_signum);
3477 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3478 }
3480 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3482 static os_sigaction_t os_sigaction = NULL;
3484 void os::Bsd::check_signal_handler(int sig) {
3485 char buf[O_BUFLEN];
3486 address jvmHandler = NULL;
3489 struct sigaction act;
3490 if (os_sigaction == NULL) {
3491 // only trust the default sigaction, in case it has been interposed
3492 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3493 if (os_sigaction == NULL) return;
3494 }
3496 os_sigaction(sig, (struct sigaction*)NULL, &act);
3499 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3501 address thisHandler = (act.sa_flags & SA_SIGINFO)
3502 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3503 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3506 switch(sig) {
3507 case SIGSEGV:
3508 case SIGBUS:
3509 case SIGFPE:
3510 case SIGPIPE:
3511 case SIGILL:
3512 case SIGXFSZ:
3513 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3514 break;
3516 case SHUTDOWN1_SIGNAL:
3517 case SHUTDOWN2_SIGNAL:
3518 case SHUTDOWN3_SIGNAL:
3519 case BREAK_SIGNAL:
3520 jvmHandler = (address)user_handler();
3521 break;
3523 case INTERRUPT_SIGNAL:
3524 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3525 break;
3527 default:
3528 if (sig == SR_signum) {
3529 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3530 } else {
3531 return;
3532 }
3533 break;
3534 }
3536 if (thisHandler != jvmHandler) {
3537 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3538 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3539 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3540 // No need to check this sig any longer
3541 sigaddset(&check_signal_done, sig);
3542 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3543 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3544 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3545 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3546 // No need to check this sig any longer
3547 sigaddset(&check_signal_done, sig);
3548 }
3550 // Dump all the signal
3551 if (sigismember(&check_signal_done, sig)) {
3552 print_signal_handlers(tty, buf, O_BUFLEN);
3553 }
3554 }
3556 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3558 extern bool signal_name(int signo, char* buf, size_t len);
3560 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3561 if (0 < exception_code && exception_code <= SIGRTMAX) {
3562 // signal
3563 if (!signal_name(exception_code, buf, size)) {
3564 jio_snprintf(buf, size, "SIG%d", exception_code);
3565 }
3566 return buf;
3567 } else {
3568 return NULL;
3569 }
3570 }
3572 // this is called _before_ the most of global arguments have been parsed
3573 void os::init(void) {
3574 char dummy; /* used to get a guess on initial stack address */
3575 // first_hrtime = gethrtime();
3577 // With BsdThreads the JavaMain thread pid (primordial thread)
3578 // is different than the pid of the java launcher thread.
3579 // So, on Bsd, the launcher thread pid is passed to the VM
3580 // via the sun.java.launcher.pid property.
3581 // Use this property instead of getpid() if it was correctly passed.
3582 // See bug 6351349.
3583 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3585 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3587 clock_tics_per_sec = CLK_TCK;
3589 init_random(1234567);
3591 ThreadCritical::initialize();
3593 Bsd::set_page_size(getpagesize());
3594 if (Bsd::page_size() == -1) {
3595 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3596 strerror(errno)));
3597 }
3598 init_page_sizes((size_t) Bsd::page_size());
3600 Bsd::initialize_system_info();
3602 // main_thread points to the aboriginal thread
3603 Bsd::_main_thread = pthread_self();
3605 Bsd::clock_init();
3606 initial_time_count = javaTimeNanos();
3608 #ifdef __APPLE__
3609 // XXXDARWIN
3610 // Work around the unaligned VM callbacks in hotspot's
3611 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3612 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3613 // alignment when doing symbol lookup. To work around this, we force early
3614 // binding of all symbols now, thus binding when alignment is known-good.
3615 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3616 #endif
3617 }
3619 // To install functions for atexit system call
3620 extern "C" {
3621 static void perfMemory_exit_helper() {
3622 perfMemory_exit();
3623 }
3624 }
3626 // this is called _after_ the global arguments have been parsed
3627 jint os::init_2(void)
3628 {
3629 // Allocate a single page and mark it as readable for safepoint polling
3630 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3631 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3633 os::set_polling_page( polling_page );
3635 #ifndef PRODUCT
3636 if(Verbose && PrintMiscellaneous)
3637 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3638 #endif
3640 if (!UseMembar) {
3641 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3642 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3643 os::set_memory_serialize_page( mem_serialize_page );
3645 #ifndef PRODUCT
3646 if(Verbose && PrintMiscellaneous)
3647 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3648 #endif
3649 }
3651 // initialize suspend/resume support - must do this before signal_sets_init()
3652 if (SR_initialize() != 0) {
3653 perror("SR_initialize failed");
3654 return JNI_ERR;
3655 }
3657 Bsd::signal_sets_init();
3658 Bsd::install_signal_handlers();
3660 // Check minimum allowable stack size for thread creation and to initialize
3661 // the java system classes, including StackOverflowError - depends on page
3662 // size. Add a page for compiler2 recursion in main thread.
3663 // Add in 2*BytesPerWord times page size to account for VM stack during
3664 // class initialization depending on 32 or 64 bit VM.
3665 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3666 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3667 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3669 size_t threadStackSizeInBytes = ThreadStackSize * K;
3670 if (threadStackSizeInBytes != 0 &&
3671 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3672 tty->print_cr("\nThe stack size specified is too small, "
3673 "Specify at least %dk",
3674 os::Bsd::min_stack_allowed/ K);
3675 return JNI_ERR;
3676 }
3678 // Make the stack size a multiple of the page size so that
3679 // the yellow/red zones can be guarded.
3680 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3681 vm_page_size()));
3683 if (MaxFDLimit) {
3684 // set the number of file descriptors to max. print out error
3685 // if getrlimit/setrlimit fails but continue regardless.
3686 struct rlimit nbr_files;
3687 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3688 if (status != 0) {
3689 if (PrintMiscellaneous && (Verbose || WizardMode))
3690 perror("os::init_2 getrlimit failed");
3691 } else {
3692 nbr_files.rlim_cur = nbr_files.rlim_max;
3694 #ifdef __APPLE__
3695 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3696 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3697 // be used instead
3698 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3699 #endif
3701 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3702 if (status != 0) {
3703 if (PrintMiscellaneous && (Verbose || WizardMode))
3704 perror("os::init_2 setrlimit failed");
3705 }
3706 }
3707 }
3709 // at-exit methods are called in the reverse order of their registration.
3710 // atexit functions are called on return from main or as a result of a
3711 // call to exit(3C). There can be only 32 of these functions registered
3712 // and atexit() does not set errno.
3714 if (PerfAllowAtExitRegistration) {
3715 // only register atexit functions if PerfAllowAtExitRegistration is set.
3716 // atexit functions can be delayed until process exit time, which
3717 // can be problematic for embedded VM situations. Embedded VMs should
3718 // call DestroyJavaVM() to assure that VM resources are released.
3720 // note: perfMemory_exit_helper atexit function may be removed in
3721 // the future if the appropriate cleanup code can be added to the
3722 // VM_Exit VMOperation's doit method.
3723 if (atexit(perfMemory_exit_helper) != 0) {
3724 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3725 }
3726 }
3728 // initialize thread priority policy
3729 prio_init();
3731 #ifdef __APPLE__
3732 // dynamically link to objective c gc registration
3733 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3734 if (handleLibObjc != NULL) {
3735 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3736 }
3737 #endif
3739 return JNI_OK;
3740 }
3742 // this is called at the end of vm_initialization
3743 void os::init_3(void) { }
3745 // Mark the polling page as unreadable
3746 void os::make_polling_page_unreadable(void) {
3747 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3748 fatal("Could not disable polling page");
3749 };
3751 // Mark the polling page as readable
3752 void os::make_polling_page_readable(void) {
3753 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3754 fatal("Could not enable polling page");
3755 }
3756 };
3758 int os::active_processor_count() {
3759 return _processor_count;
3760 }
3762 void os::set_native_thread_name(const char *name) {
3763 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3764 // This is only supported in Snow Leopard and beyond
3765 if (name != NULL) {
3766 // Add a "Java: " prefix to the name
3767 char buf[MAXTHREADNAMESIZE];
3768 snprintf(buf, sizeof(buf), "Java: %s", name);
3769 pthread_setname_np(buf);
3770 }
3771 #endif
3772 }
3774 bool os::distribute_processes(uint length, uint* distribution) {
3775 // Not yet implemented.
3776 return false;
3777 }
3779 bool os::bind_to_processor(uint processor_id) {
3780 // Not yet implemented.
3781 return false;
3782 }
3784 void os::SuspendedThreadTask::internal_do_task() {
3785 if (do_suspend(_thread->osthread())) {
3786 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3787 do_task(context);
3788 do_resume(_thread->osthread());
3789 }
3790 }
3792 ///
3793 class PcFetcher : public os::SuspendedThreadTask {
3794 public:
3795 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3796 ExtendedPC result();
3797 protected:
3798 void do_task(const os::SuspendedThreadTaskContext& context);
3799 private:
3800 ExtendedPC _epc;
3801 };
3803 ExtendedPC PcFetcher::result() {
3804 guarantee(is_done(), "task is not done yet.");
3805 return _epc;
3806 }
3808 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3809 Thread* thread = context.thread();
3810 OSThread* osthread = thread->osthread();
3811 if (osthread->ucontext() != NULL) {
3812 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3813 } else {
3814 // NULL context is unexpected, double-check this is the VMThread
3815 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3816 }
3817 }
3819 // Suspends the target using the signal mechanism and then grabs the PC before
3820 // resuming the target. Used by the flat-profiler only
3821 ExtendedPC os::get_thread_pc(Thread* thread) {
3822 // Make sure that it is called by the watcher for the VMThread
3823 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3824 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3826 PcFetcher fetcher(thread);
3827 fetcher.run();
3828 return fetcher.result();
3829 }
3831 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3832 {
3833 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3834 }
3836 ////////////////////////////////////////////////////////////////////////////////
3837 // debug support
3839 bool os::find(address addr, outputStream* st) {
3840 Dl_info dlinfo;
3841 memset(&dlinfo, 0, sizeof(dlinfo));
3842 if (dladdr(addr, &dlinfo) != 0) {
3843 st->print(PTR_FORMAT ": ", addr);
3844 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3845 st->print("%s+%#x", dlinfo.dli_sname,
3846 addr - (intptr_t)dlinfo.dli_saddr);
3847 } else if (dlinfo.dli_fbase != NULL) {
3848 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3849 } else {
3850 st->print("<absolute address>");
3851 }
3852 if (dlinfo.dli_fname != NULL) {
3853 st->print(" in %s", dlinfo.dli_fname);
3854 }
3855 if (dlinfo.dli_fbase != NULL) {
3856 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3857 }
3858 st->cr();
3860 if (Verbose) {
3861 // decode some bytes around the PC
3862 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3863 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3864 address lowest = (address) dlinfo.dli_sname;
3865 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3866 if (begin < lowest) begin = lowest;
3867 Dl_info dlinfo2;
3868 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3869 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3870 end = (address) dlinfo2.dli_saddr;
3871 Disassembler::decode(begin, end, st);
3872 }
3873 return true;
3874 }
3875 return false;
3876 }
3878 ////////////////////////////////////////////////////////////////////////////////
3879 // misc
3881 // This does not do anything on Bsd. This is basically a hook for being
3882 // able to use structured exception handling (thread-local exception filters)
3883 // on, e.g., Win32.
3884 void
3885 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3886 JavaCallArguments* args, Thread* thread) {
3887 f(value, method, args, thread);
3888 }
3890 void os::print_statistics() {
3891 }
3893 int os::message_box(const char* title, const char* message) {
3894 int i;
3895 fdStream err(defaultStream::error_fd());
3896 for (i = 0; i < 78; i++) err.print_raw("=");
3897 err.cr();
3898 err.print_raw_cr(title);
3899 for (i = 0; i < 78; i++) err.print_raw("-");
3900 err.cr();
3901 err.print_raw_cr(message);
3902 for (i = 0; i < 78; i++) err.print_raw("=");
3903 err.cr();
3905 char buf[16];
3906 // Prevent process from exiting upon "read error" without consuming all CPU
3907 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3909 return buf[0] == 'y' || buf[0] == 'Y';
3910 }
3912 int os::stat(const char *path, struct stat *sbuf) {
3913 char pathbuf[MAX_PATH];
3914 if (strlen(path) > MAX_PATH - 1) {
3915 errno = ENAMETOOLONG;
3916 return -1;
3917 }
3918 os::native_path(strcpy(pathbuf, path));
3919 return ::stat(pathbuf, sbuf);
3920 }
3922 bool os::check_heap(bool force) {
3923 return true;
3924 }
3926 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3927 return ::vsnprintf(buf, count, format, args);
3928 }
3930 // Is a (classpath) directory empty?
3931 bool os::dir_is_empty(const char* path) {
3932 DIR *dir = NULL;
3933 struct dirent *ptr;
3935 dir = opendir(path);
3936 if (dir == NULL) return true;
3938 /* Scan the directory */
3939 bool result = true;
3940 char buf[sizeof(struct dirent) + MAX_PATH];
3941 while (result && (ptr = ::readdir(dir)) != NULL) {
3942 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3943 result = false;
3944 }
3945 }
3946 closedir(dir);
3947 return result;
3948 }
3950 // This code originates from JDK's sysOpen and open64_w
3951 // from src/solaris/hpi/src/system_md.c
3953 #ifndef O_DELETE
3954 #define O_DELETE 0x10000
3955 #endif
3957 // Open a file. Unlink the file immediately after open returns
3958 // if the specified oflag has the O_DELETE flag set.
3959 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3961 int os::open(const char *path, int oflag, int mode) {
3963 if (strlen(path) > MAX_PATH - 1) {
3964 errno = ENAMETOOLONG;
3965 return -1;
3966 }
3967 int fd;
3968 int o_delete = (oflag & O_DELETE);
3969 oflag = oflag & ~O_DELETE;
3971 fd = ::open(path, oflag, mode);
3972 if (fd == -1) return -1;
3974 //If the open succeeded, the file might still be a directory
3975 {
3976 struct stat buf;
3977 int ret = ::fstat(fd, &buf);
3978 int st_mode = buf.st_mode;
3980 if (ret != -1) {
3981 if ((st_mode & S_IFMT) == S_IFDIR) {
3982 errno = EISDIR;
3983 ::close(fd);
3984 return -1;
3985 }
3986 } else {
3987 ::close(fd);
3988 return -1;
3989 }
3990 }
3992 /*
3993 * All file descriptors that are opened in the JVM and not
3994 * specifically destined for a subprocess should have the
3995 * close-on-exec flag set. If we don't set it, then careless 3rd
3996 * party native code might fork and exec without closing all
3997 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3998 * UNIXProcess.c), and this in turn might:
3999 *
4000 * - cause end-of-file to fail to be detected on some file
4001 * descriptors, resulting in mysterious hangs, or
4002 *
4003 * - might cause an fopen in the subprocess to fail on a system
4004 * suffering from bug 1085341.
4005 *
4006 * (Yes, the default setting of the close-on-exec flag is a Unix
4007 * design flaw)
4008 *
4009 * See:
4010 * 1085341: 32-bit stdio routines should support file descriptors >255
4011 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4012 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4013 */
4014 #ifdef FD_CLOEXEC
4015 {
4016 int flags = ::fcntl(fd, F_GETFD);
4017 if (flags != -1)
4018 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4019 }
4020 #endif
4022 if (o_delete != 0) {
4023 ::unlink(path);
4024 }
4025 return fd;
4026 }
4029 // create binary file, rewriting existing file if required
4030 int os::create_binary_file(const char* path, bool rewrite_existing) {
4031 int oflags = O_WRONLY | O_CREAT;
4032 if (!rewrite_existing) {
4033 oflags |= O_EXCL;
4034 }
4035 return ::open(path, oflags, S_IREAD | S_IWRITE);
4036 }
4038 // return current position of file pointer
4039 jlong os::current_file_offset(int fd) {
4040 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4041 }
4043 // move file pointer to the specified offset
4044 jlong os::seek_to_file_offset(int fd, jlong offset) {
4045 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4046 }
4048 // This code originates from JDK's sysAvailable
4049 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4051 int os::available(int fd, jlong *bytes) {
4052 jlong cur, end;
4053 int mode;
4054 struct stat buf;
4056 if (::fstat(fd, &buf) >= 0) {
4057 mode = buf.st_mode;
4058 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4059 /*
4060 * XXX: is the following call interruptible? If so, this might
4061 * need to go through the INTERRUPT_IO() wrapper as for other
4062 * blocking, interruptible calls in this file.
4063 */
4064 int n;
4065 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4066 *bytes = n;
4067 return 1;
4068 }
4069 }
4070 }
4071 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4072 return 0;
4073 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4074 return 0;
4075 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4076 return 0;
4077 }
4078 *bytes = end - cur;
4079 return 1;
4080 }
4082 int os::socket_available(int fd, jint *pbytes) {
4083 if (fd < 0)
4084 return OS_OK;
4086 int ret;
4088 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4090 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4091 // is expected to return 0 on failure and 1 on success to the jdk.
4093 return (ret == OS_ERR) ? 0 : 1;
4094 }
4096 // Map a block of memory.
4097 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4098 char *addr, size_t bytes, bool read_only,
4099 bool allow_exec) {
4100 int prot;
4101 int flags;
4103 if (read_only) {
4104 prot = PROT_READ;
4105 flags = MAP_SHARED;
4106 } else {
4107 prot = PROT_READ | PROT_WRITE;
4108 flags = MAP_PRIVATE;
4109 }
4111 if (allow_exec) {
4112 prot |= PROT_EXEC;
4113 }
4115 if (addr != NULL) {
4116 flags |= MAP_FIXED;
4117 }
4119 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4120 fd, file_offset);
4121 if (mapped_address == MAP_FAILED) {
4122 return NULL;
4123 }
4124 return mapped_address;
4125 }
4128 // Remap a block of memory.
4129 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4130 char *addr, size_t bytes, bool read_only,
4131 bool allow_exec) {
4132 // same as map_memory() on this OS
4133 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4134 allow_exec);
4135 }
4138 // Unmap a block of memory.
4139 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4140 return munmap(addr, bytes) == 0;
4141 }
4143 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4144 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4145 // of a thread.
4146 //
4147 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4148 // the fast estimate available on the platform.
4150 jlong os::current_thread_cpu_time() {
4151 #ifdef __APPLE__
4152 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4153 #else
4154 Unimplemented();
4155 return 0;
4156 #endif
4157 }
4159 jlong os::thread_cpu_time(Thread* thread) {
4160 #ifdef __APPLE__
4161 return os::thread_cpu_time(thread, true /* user + sys */);
4162 #else
4163 Unimplemented();
4164 return 0;
4165 #endif
4166 }
4168 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4169 #ifdef __APPLE__
4170 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4171 #else
4172 Unimplemented();
4173 return 0;
4174 #endif
4175 }
4177 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4178 #ifdef __APPLE__
4179 struct thread_basic_info tinfo;
4180 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4181 kern_return_t kr;
4182 thread_t mach_thread;
4184 mach_thread = thread->osthread()->thread_id();
4185 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4186 if (kr != KERN_SUCCESS)
4187 return -1;
4189 if (user_sys_cpu_time) {
4190 jlong nanos;
4191 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4192 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4193 return nanos;
4194 } else {
4195 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4196 }
4197 #else
4198 Unimplemented();
4199 return 0;
4200 #endif
4201 }
4204 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4205 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4206 info_ptr->may_skip_backward = false; // elapsed time not wall time
4207 info_ptr->may_skip_forward = false; // elapsed time not wall time
4208 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4209 }
4211 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4212 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4213 info_ptr->may_skip_backward = false; // elapsed time not wall time
4214 info_ptr->may_skip_forward = false; // elapsed time not wall time
4215 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4216 }
4218 bool os::is_thread_cpu_time_supported() {
4219 #ifdef __APPLE__
4220 return true;
4221 #else
4222 return false;
4223 #endif
4224 }
4226 // System loadavg support. Returns -1 if load average cannot be obtained.
4227 // Bsd doesn't yet have a (official) notion of processor sets,
4228 // so just return the system wide load average.
4229 int os::loadavg(double loadavg[], int nelem) {
4230 return ::getloadavg(loadavg, nelem);
4231 }
4233 void os::pause() {
4234 char filename[MAX_PATH];
4235 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4236 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4237 } else {
4238 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4239 }
4241 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4242 if (fd != -1) {
4243 struct stat buf;
4244 ::close(fd);
4245 while (::stat(filename, &buf) == 0) {
4246 (void)::poll(NULL, 0, 100);
4247 }
4248 } else {
4249 jio_fprintf(stderr,
4250 "Could not open pause file '%s', continuing immediately.\n", filename);
4251 }
4252 }
4255 // Refer to the comments in os_solaris.cpp park-unpark.
4256 //
4257 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4258 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4259 // For specifics regarding the bug see GLIBC BUGID 261237 :
4260 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4261 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4262 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4263 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4264 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4265 // and monitorenter when we're using 1-0 locking. All those operations may result in
4266 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4267 // of libpthread avoids the problem, but isn't practical.
4268 //
4269 // Possible remedies:
4270 //
4271 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4272 // This is palliative and probabilistic, however. If the thread is preempted
4273 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4274 // than the minimum period may have passed, and the abstime may be stale (in the
4275 // past) resultin in a hang. Using this technique reduces the odds of a hang
4276 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4277 //
4278 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4279 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4280 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4281 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4282 // thread.
4283 //
4284 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4285 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4286 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4287 // This also works well. In fact it avoids kernel-level scalability impediments
4288 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4289 // timers in a graceful fashion.
4290 //
4291 // 4. When the abstime value is in the past it appears that control returns
4292 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4293 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4294 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4295 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4296 // It may be possible to avoid reinitialization by checking the return
4297 // value from pthread_cond_timedwait(). In addition to reinitializing the
4298 // condvar we must establish the invariant that cond_signal() is only called
4299 // within critical sections protected by the adjunct mutex. This prevents
4300 // cond_signal() from "seeing" a condvar that's in the midst of being
4301 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4302 // desirable signal-after-unlock optimization that avoids futile context switching.
4303 //
4304 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4305 // structure when a condvar is used or initialized. cond_destroy() would
4306 // release the helper structure. Our reinitialize-after-timedwait fix
4307 // put excessive stress on malloc/free and locks protecting the c-heap.
4308 //
4309 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4310 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4311 // and only enabling the work-around for vulnerable environments.
4313 // utility to compute the abstime argument to timedwait:
4314 // millis is the relative timeout time
4315 // abstime will be the absolute timeout time
4316 // TODO: replace compute_abstime() with unpackTime()
4318 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4319 if (millis < 0) millis = 0;
4320 struct timeval now;
4321 int status = gettimeofday(&now, NULL);
4322 assert(status == 0, "gettimeofday");
4323 jlong seconds = millis / 1000;
4324 millis %= 1000;
4325 if (seconds > 50000000) { // see man cond_timedwait(3T)
4326 seconds = 50000000;
4327 }
4328 abstime->tv_sec = now.tv_sec + seconds;
4329 long usec = now.tv_usec + millis * 1000;
4330 if (usec >= 1000000) {
4331 abstime->tv_sec += 1;
4332 usec -= 1000000;
4333 }
4334 abstime->tv_nsec = usec * 1000;
4335 return abstime;
4336 }
4339 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4340 // Conceptually TryPark() should be equivalent to park(0).
4342 int os::PlatformEvent::TryPark() {
4343 for (;;) {
4344 const int v = _Event ;
4345 guarantee ((v == 0) || (v == 1), "invariant") ;
4346 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4347 }
4348 }
4350 void os::PlatformEvent::park() { // AKA "down()"
4351 // Invariant: Only the thread associated with the Event/PlatformEvent
4352 // may call park().
4353 // TODO: assert that _Assoc != NULL or _Assoc == Self
4354 int v ;
4355 for (;;) {
4356 v = _Event ;
4357 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4358 }
4359 guarantee (v >= 0, "invariant") ;
4360 if (v == 0) {
4361 // Do this the hard way by blocking ...
4362 int status = pthread_mutex_lock(_mutex);
4363 assert_status(status == 0, status, "mutex_lock");
4364 guarantee (_nParked == 0, "invariant") ;
4365 ++ _nParked ;
4366 while (_Event < 0) {
4367 status = pthread_cond_wait(_cond, _mutex);
4368 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4369 // Treat this the same as if the wait was interrupted
4370 if (status == ETIMEDOUT) { status = EINTR; }
4371 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4372 }
4373 -- _nParked ;
4375 _Event = 0 ;
4376 status = pthread_mutex_unlock(_mutex);
4377 assert_status(status == 0, status, "mutex_unlock");
4378 // Paranoia to ensure our locked and lock-free paths interact
4379 // correctly with each other.
4380 OrderAccess::fence();
4381 }
4382 guarantee (_Event >= 0, "invariant") ;
4383 }
4385 int os::PlatformEvent::park(jlong millis) {
4386 guarantee (_nParked == 0, "invariant") ;
4388 int v ;
4389 for (;;) {
4390 v = _Event ;
4391 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4392 }
4393 guarantee (v >= 0, "invariant") ;
4394 if (v != 0) return OS_OK ;
4396 // We do this the hard way, by blocking the thread.
4397 // Consider enforcing a minimum timeout value.
4398 struct timespec abst;
4399 compute_abstime(&abst, millis);
4401 int ret = OS_TIMEOUT;
4402 int status = pthread_mutex_lock(_mutex);
4403 assert_status(status == 0, status, "mutex_lock");
4404 guarantee (_nParked == 0, "invariant") ;
4405 ++_nParked ;
4407 // Object.wait(timo) will return because of
4408 // (a) notification
4409 // (b) timeout
4410 // (c) thread.interrupt
4411 //
4412 // Thread.interrupt and object.notify{All} both call Event::set.
4413 // That is, we treat thread.interrupt as a special case of notification.
4414 // The underlying Solaris implementation, cond_timedwait, admits
4415 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4416 // JVM from making those visible to Java code. As such, we must
4417 // filter out spurious wakeups. We assume all ETIME returns are valid.
4418 //
4419 // TODO: properly differentiate simultaneous notify+interrupt.
4420 // In that case, we should propagate the notify to another waiter.
4422 while (_Event < 0) {
4423 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4424 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4425 pthread_cond_destroy (_cond);
4426 pthread_cond_init (_cond, NULL) ;
4427 }
4428 assert_status(status == 0 || status == EINTR ||
4429 status == ETIMEDOUT,
4430 status, "cond_timedwait");
4431 if (!FilterSpuriousWakeups) break ; // previous semantics
4432 if (status == ETIMEDOUT) break ;
4433 // We consume and ignore EINTR and spurious wakeups.
4434 }
4435 --_nParked ;
4436 if (_Event >= 0) {
4437 ret = OS_OK;
4438 }
4439 _Event = 0 ;
4440 status = pthread_mutex_unlock(_mutex);
4441 assert_status(status == 0, status, "mutex_unlock");
4442 assert (_nParked == 0, "invariant") ;
4443 // Paranoia to ensure our locked and lock-free paths interact
4444 // correctly with each other.
4445 OrderAccess::fence();
4446 return ret;
4447 }
4449 void os::PlatformEvent::unpark() {
4450 // Transitions for _Event:
4451 // 0 :=> 1
4452 // 1 :=> 1
4453 // -1 :=> either 0 or 1; must signal target thread
4454 // That is, we can safely transition _Event from -1 to either
4455 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4456 // unpark() calls.
4457 // See also: "Semaphores in Plan 9" by Mullender & Cox
4458 //
4459 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4460 // that it will take two back-to-back park() calls for the owning
4461 // thread to block. This has the benefit of forcing a spurious return
4462 // from the first park() call after an unpark() call which will help
4463 // shake out uses of park() and unpark() without condition variables.
4465 if (Atomic::xchg(1, &_Event) >= 0) return;
4467 // Wait for the thread associated with the event to vacate
4468 int status = pthread_mutex_lock(_mutex);
4469 assert_status(status == 0, status, "mutex_lock");
4470 int AnyWaiters = _nParked;
4471 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4472 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4473 AnyWaiters = 0;
4474 pthread_cond_signal(_cond);
4475 }
4476 status = pthread_mutex_unlock(_mutex);
4477 assert_status(status == 0, status, "mutex_unlock");
4478 if (AnyWaiters != 0) {
4479 status = pthread_cond_signal(_cond);
4480 assert_status(status == 0, status, "cond_signal");
4481 }
4483 // Note that we signal() _after dropping the lock for "immortal" Events.
4484 // This is safe and avoids a common class of futile wakeups. In rare
4485 // circumstances this can cause a thread to return prematurely from
4486 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4487 // simply re-test the condition and re-park itself.
4488 }
4491 // JSR166
4492 // -------------------------------------------------------
4494 /*
4495 * The solaris and bsd implementations of park/unpark are fairly
4496 * conservative for now, but can be improved. They currently use a
4497 * mutex/condvar pair, plus a a count.
4498 * Park decrements count if > 0, else does a condvar wait. Unpark
4499 * sets count to 1 and signals condvar. Only one thread ever waits
4500 * on the condvar. Contention seen when trying to park implies that someone
4501 * is unparking you, so don't wait. And spurious returns are fine, so there
4502 * is no need to track notifications.
4503 */
4505 #define MAX_SECS 100000000
4506 /*
4507 * This code is common to bsd and solaris and will be moved to a
4508 * common place in dolphin.
4509 *
4510 * The passed in time value is either a relative time in nanoseconds
4511 * or an absolute time in milliseconds. Either way it has to be unpacked
4512 * into suitable seconds and nanoseconds components and stored in the
4513 * given timespec structure.
4514 * Given time is a 64-bit value and the time_t used in the timespec is only
4515 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4516 * overflow if times way in the future are given. Further on Solaris versions
4517 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4518 * number of seconds, in abstime, is less than current_time + 100,000,000.
4519 * As it will be 28 years before "now + 100000000" will overflow we can
4520 * ignore overflow and just impose a hard-limit on seconds using the value
4521 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4522 * years from "now".
4523 */
4525 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4526 assert (time > 0, "convertTime");
4528 struct timeval now;
4529 int status = gettimeofday(&now, NULL);
4530 assert(status == 0, "gettimeofday");
4532 time_t max_secs = now.tv_sec + MAX_SECS;
4534 if (isAbsolute) {
4535 jlong secs = time / 1000;
4536 if (secs > max_secs) {
4537 absTime->tv_sec = max_secs;
4538 }
4539 else {
4540 absTime->tv_sec = secs;
4541 }
4542 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4543 }
4544 else {
4545 jlong secs = time / NANOSECS_PER_SEC;
4546 if (secs >= MAX_SECS) {
4547 absTime->tv_sec = max_secs;
4548 absTime->tv_nsec = 0;
4549 }
4550 else {
4551 absTime->tv_sec = now.tv_sec + secs;
4552 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4553 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4554 absTime->tv_nsec -= NANOSECS_PER_SEC;
4555 ++absTime->tv_sec; // note: this must be <= max_secs
4556 }
4557 }
4558 }
4559 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4560 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4561 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4562 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4563 }
4565 void Parker::park(bool isAbsolute, jlong time) {
4566 // Ideally we'd do something useful while spinning, such
4567 // as calling unpackTime().
4569 // Optional fast-path check:
4570 // Return immediately if a permit is available.
4571 // We depend on Atomic::xchg() having full barrier semantics
4572 // since we are doing a lock-free update to _counter.
4573 if (Atomic::xchg(0, &_counter) > 0) return;
4575 Thread* thread = Thread::current();
4576 assert(thread->is_Java_thread(), "Must be JavaThread");
4577 JavaThread *jt = (JavaThread *)thread;
4579 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4580 // Check interrupt before trying to wait
4581 if (Thread::is_interrupted(thread, false)) {
4582 return;
4583 }
4585 // Next, demultiplex/decode time arguments
4586 struct timespec absTime;
4587 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4588 return;
4589 }
4590 if (time > 0) {
4591 unpackTime(&absTime, isAbsolute, time);
4592 }
4595 // Enter safepoint region
4596 // Beware of deadlocks such as 6317397.
4597 // The per-thread Parker:: mutex is a classic leaf-lock.
4598 // In particular a thread must never block on the Threads_lock while
4599 // holding the Parker:: mutex. If safepoints are pending both the
4600 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4601 ThreadBlockInVM tbivm(jt);
4603 // Don't wait if cannot get lock since interference arises from
4604 // unblocking. Also. check interrupt before trying wait
4605 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4606 return;
4607 }
4609 int status ;
4610 if (_counter > 0) { // no wait needed
4611 _counter = 0;
4612 status = pthread_mutex_unlock(_mutex);
4613 assert (status == 0, "invariant") ;
4614 // Paranoia to ensure our locked and lock-free paths interact
4615 // correctly with each other and Java-level accesses.
4616 OrderAccess::fence();
4617 return;
4618 }
4620 #ifdef ASSERT
4621 // Don't catch signals while blocked; let the running threads have the signals.
4622 // (This allows a debugger to break into the running thread.)
4623 sigset_t oldsigs;
4624 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4625 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4626 #endif
4628 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4629 jt->set_suspend_equivalent();
4630 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4632 if (time == 0) {
4633 status = pthread_cond_wait (_cond, _mutex) ;
4634 } else {
4635 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4636 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4637 pthread_cond_destroy (_cond) ;
4638 pthread_cond_init (_cond, NULL);
4639 }
4640 }
4641 assert_status(status == 0 || status == EINTR ||
4642 status == ETIMEDOUT,
4643 status, "cond_timedwait");
4645 #ifdef ASSERT
4646 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4647 #endif
4649 _counter = 0 ;
4650 status = pthread_mutex_unlock(_mutex) ;
4651 assert_status(status == 0, status, "invariant") ;
4652 // Paranoia to ensure our locked and lock-free paths interact
4653 // correctly with each other and Java-level accesses.
4654 OrderAccess::fence();
4656 // If externally suspended while waiting, re-suspend
4657 if (jt->handle_special_suspend_equivalent_condition()) {
4658 jt->java_suspend_self();
4659 }
4660 }
4662 void Parker::unpark() {
4663 int s, status ;
4664 status = pthread_mutex_lock(_mutex);
4665 assert (status == 0, "invariant") ;
4666 s = _counter;
4667 _counter = 1;
4668 if (s < 1) {
4669 if (WorkAroundNPTLTimedWaitHang) {
4670 status = pthread_cond_signal (_cond) ;
4671 assert (status == 0, "invariant") ;
4672 status = pthread_mutex_unlock(_mutex);
4673 assert (status == 0, "invariant") ;
4674 } else {
4675 status = pthread_mutex_unlock(_mutex);
4676 assert (status == 0, "invariant") ;
4677 status = pthread_cond_signal (_cond) ;
4678 assert (status == 0, "invariant") ;
4679 }
4680 } else {
4681 pthread_mutex_unlock(_mutex);
4682 assert (status == 0, "invariant") ;
4683 }
4684 }
4687 /* Darwin has no "environ" in a dynamic library. */
4688 #ifdef __APPLE__
4689 #include <crt_externs.h>
4690 #define environ (*_NSGetEnviron())
4691 #else
4692 extern char** environ;
4693 #endif
4695 // Run the specified command in a separate process. Return its exit value,
4696 // or -1 on failure (e.g. can't fork a new process).
4697 // Unlike system(), this function can be called from signal handler. It
4698 // doesn't block SIGINT et al.
4699 int os::fork_and_exec(char* cmd) {
4700 const char * argv[4] = {"sh", "-c", cmd, NULL};
4702 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4703 // pthread_atfork handlers and reset pthread library. All we need is a
4704 // separate process to execve. Make a direct syscall to fork process.
4705 // On IA64 there's no fork syscall, we have to use fork() and hope for
4706 // the best...
4707 pid_t pid = fork();
4709 if (pid < 0) {
4710 // fork failed
4711 return -1;
4713 } else if (pid == 0) {
4714 // child process
4716 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4717 // first to kill every thread on the thread list. Because this list is
4718 // not reset by fork() (see notes above), execve() will instead kill
4719 // every thread in the parent process. We know this is the only thread
4720 // in the new process, so make a system call directly.
4721 // IA64 should use normal execve() from glibc to match the glibc fork()
4722 // above.
4723 execve("/bin/sh", (char* const*)argv, environ);
4725 // execve failed
4726 _exit(-1);
4728 } else {
4729 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4730 // care about the actual exit code, for now.
4732 int status;
4734 // Wait for the child process to exit. This returns immediately if
4735 // the child has already exited. */
4736 while (waitpid(pid, &status, 0) < 0) {
4737 switch (errno) {
4738 case ECHILD: return 0;
4739 case EINTR: break;
4740 default: return -1;
4741 }
4742 }
4744 if (WIFEXITED(status)) {
4745 // The child exited normally; get its exit code.
4746 return WEXITSTATUS(status);
4747 } else if (WIFSIGNALED(status)) {
4748 // The child exited because of a signal
4749 // The best value to return is 0x80 + signal number,
4750 // because that is what all Unix shells do, and because
4751 // it allows callers to distinguish between process exit and
4752 // process death by signal.
4753 return 0x80 + WTERMSIG(status);
4754 } else {
4755 // Unknown exit code; pass it through
4756 return status;
4757 }
4758 }
4759 }
4761 // is_headless_jre()
4762 //
4763 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4764 // in order to report if we are running in a headless jre
4765 //
4766 // Since JDK8 xawt/libmawt.so was moved into the same directory
4767 // as libawt.so, and renamed libawt_xawt.so
4768 //
4769 bool os::is_headless_jre() {
4770 #ifdef __APPLE__
4771 // We no longer build headless-only on Mac OS X
4772 return false;
4773 #else
4774 struct stat statbuf;
4775 char buf[MAXPATHLEN];
4776 char libmawtpath[MAXPATHLEN];
4777 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4778 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4779 char *p;
4781 // Get path to libjvm.so
4782 os::jvm_path(buf, sizeof(buf));
4784 // Get rid of libjvm.so
4785 p = strrchr(buf, '/');
4786 if (p == NULL) return false;
4787 else *p = '\0';
4789 // Get rid of client or server
4790 p = strrchr(buf, '/');
4791 if (p == NULL) return false;
4792 else *p = '\0';
4794 // check xawt/libmawt.so
4795 strcpy(libmawtpath, buf);
4796 strcat(libmawtpath, xawtstr);
4797 if (::stat(libmawtpath, &statbuf) == 0) return false;
4799 // check libawt_xawt.so
4800 strcpy(libmawtpath, buf);
4801 strcat(libmawtpath, new_xawtstr);
4802 if (::stat(libmawtpath, &statbuf) == 0) return false;
4804 return true;
4805 #endif
4806 }
4808 // Get the default path to the core file
4809 // Returns the length of the string
4810 int os::get_core_path(char* buffer, size_t bufferSize) {
4811 int n = jio_snprintf(buffer, bufferSize, "/cores");
4813 // Truncate if theoretical string was longer than bufferSize
4814 n = MIN2(n, (int)bufferSize);
4816 return n;
4817 }
4819 #ifndef PRODUCT
4820 void TestReserveMemorySpecial_test() {
4821 // No tests available for this platform
4822 }
4823 #endif