Wed, 02 Apr 2014 18:40:52 +0200
8033696: "assert(thread != NULL) failed: just checking" due to Thread::current() and JNI pthread interaction
Reviewed-by: dholmes, dsamersoff
Contributed-by: andreas.eriksson@oracle.com
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(PPC32)
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 // Restore the thread pointer if the destructor is called. This is in case
918 // someone from JNI code sets up a destructor with pthread_key_create to run
919 // detachCurrentThread on thread death. Unless we restore the thread pointer we
920 // will hang or crash. When detachCurrentThread is called the key will be set
921 // to null and we will not be called again. If detachCurrentThread is never
922 // called we could loop forever depending on the pthread implementation.
923 static void restore_thread_pointer(void* p) {
924 Thread* thread = (Thread*) p;
925 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
926 }
928 int os::allocate_thread_local_storage() {
929 pthread_key_t key;
930 int rslt = pthread_key_create(&key, restore_thread_pointer);
931 assert(rslt == 0, "cannot allocate thread local storage");
932 return (int)key;
933 }
935 // Note: This is currently not used by VM, as we don't destroy TLS key
936 // on VM exit.
937 void os::free_thread_local_storage(int index) {
938 int rslt = pthread_key_delete((pthread_key_t)index);
939 assert(rslt == 0, "invalid index");
940 }
942 void os::thread_local_storage_at_put(int index, void* value) {
943 int rslt = pthread_setspecific((pthread_key_t)index, value);
944 assert(rslt == 0, "pthread_setspecific failed");
945 }
947 extern "C" Thread* get_thread() {
948 return ThreadLocalStorage::thread();
949 }
952 ////////////////////////////////////////////////////////////////////////////////
953 // time support
955 // Time since start-up in seconds to a fine granularity.
956 // Used by VMSelfDestructTimer and the MemProfiler.
957 double os::elapsedTime() {
959 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
960 }
962 jlong os::elapsed_counter() {
963 return javaTimeNanos() - initial_time_count;
964 }
966 jlong os::elapsed_frequency() {
967 return NANOSECS_PER_SEC; // nanosecond resolution
968 }
970 bool os::supports_vtime() { return true; }
971 bool os::enable_vtime() { return false; }
972 bool os::vtime_enabled() { return false; }
974 double os::elapsedVTime() {
975 // better than nothing, but not much
976 return elapsedTime();
977 }
979 jlong os::javaTimeMillis() {
980 timeval time;
981 int status = gettimeofday(&time, NULL);
982 assert(status != -1, "bsd error");
983 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
984 }
986 #ifndef CLOCK_MONOTONIC
987 #define CLOCK_MONOTONIC (1)
988 #endif
990 #ifdef __APPLE__
991 void os::Bsd::clock_init() {
992 // XXXDARWIN: Investigate replacement monotonic clock
993 }
994 #else
995 void os::Bsd::clock_init() {
996 struct timespec res;
997 struct timespec tp;
998 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
999 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
1000 // yes, monotonic clock is supported
1001 _clock_gettime = ::clock_gettime;
1002 }
1003 }
1004 #endif
1007 jlong os::javaTimeNanos() {
1008 if (Bsd::supports_monotonic_clock()) {
1009 struct timespec tp;
1010 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1011 assert(status == 0, "gettime error");
1012 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1013 return result;
1014 } else {
1015 timeval time;
1016 int status = gettimeofday(&time, NULL);
1017 assert(status != -1, "bsd error");
1018 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1019 return 1000 * usecs;
1020 }
1021 }
1023 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1024 if (Bsd::supports_monotonic_clock()) {
1025 info_ptr->max_value = ALL_64_BITS;
1027 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1028 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1029 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1030 } else {
1031 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1032 info_ptr->max_value = ALL_64_BITS;
1034 // gettimeofday is a real time clock so it skips
1035 info_ptr->may_skip_backward = true;
1036 info_ptr->may_skip_forward = true;
1037 }
1039 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1040 }
1042 // Return the real, user, and system times in seconds from an
1043 // arbitrary fixed point in the past.
1044 bool os::getTimesSecs(double* process_real_time,
1045 double* process_user_time,
1046 double* process_system_time) {
1047 struct tms ticks;
1048 clock_t real_ticks = times(&ticks);
1050 if (real_ticks == (clock_t) (-1)) {
1051 return false;
1052 } else {
1053 double ticks_per_second = (double) clock_tics_per_sec;
1054 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1055 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1056 *process_real_time = ((double) real_ticks) / ticks_per_second;
1058 return true;
1059 }
1060 }
1063 char * os::local_time_string(char *buf, size_t buflen) {
1064 struct tm t;
1065 time_t long_time;
1066 time(&long_time);
1067 localtime_r(&long_time, &t);
1068 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1069 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1070 t.tm_hour, t.tm_min, t.tm_sec);
1071 return buf;
1072 }
1074 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1075 return localtime_r(clock, res);
1076 }
1078 ////////////////////////////////////////////////////////////////////////////////
1079 // runtime exit support
1081 // Note: os::shutdown() might be called very early during initialization, or
1082 // called from signal handler. Before adding something to os::shutdown(), make
1083 // sure it is async-safe and can handle partially initialized VM.
1084 void os::shutdown() {
1086 // allow PerfMemory to attempt cleanup of any persistent resources
1087 perfMemory_exit();
1089 // needs to remove object in file system
1090 AttachListener::abort();
1092 // flush buffered output, finish log files
1093 ostream_abort();
1095 // Check for abort hook
1096 abort_hook_t abort_hook = Arguments::abort_hook();
1097 if (abort_hook != NULL) {
1098 abort_hook();
1099 }
1101 }
1103 // Note: os::abort() might be called very early during initialization, or
1104 // called from signal handler. Before adding something to os::abort(), make
1105 // sure it is async-safe and can handle partially initialized VM.
1106 void os::abort(bool dump_core) {
1107 os::shutdown();
1108 if (dump_core) {
1109 #ifndef PRODUCT
1110 fdStream out(defaultStream::output_fd());
1111 out.print_raw("Current thread is ");
1112 char buf[16];
1113 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1114 out.print_raw_cr(buf);
1115 out.print_raw_cr("Dumping core ...");
1116 #endif
1117 ::abort(); // dump core
1118 }
1120 ::exit(1);
1121 }
1123 // Die immediately, no exit hook, no abort hook, no cleanup.
1124 void os::die() {
1125 // _exit() on BsdThreads only kills current thread
1126 ::abort();
1127 }
1129 // unused on bsd for now.
1130 void os::set_error_file(const char *logfile) {}
1133 // This method is a copy of JDK's sysGetLastErrorString
1134 // from src/solaris/hpi/src/system_md.c
1136 size_t os::lasterror(char *buf, size_t len) {
1138 if (errno == 0) return 0;
1140 const char *s = ::strerror(errno);
1141 size_t n = ::strlen(s);
1142 if (n >= len) {
1143 n = len - 1;
1144 }
1145 ::strncpy(buf, s, n);
1146 buf[n] = '\0';
1147 return n;
1148 }
1150 // Information of current thread in variety of formats
1151 pid_t os::Bsd::gettid() {
1152 int retval = -1;
1154 #ifdef __APPLE__ //XNU kernel
1155 // despite the fact mach port is actually not a thread id use it
1156 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1157 retval = ::pthread_mach_thread_np(::pthread_self());
1158 guarantee(retval != 0, "just checking");
1159 return retval;
1161 #elif __FreeBSD__
1162 retval = syscall(SYS_thr_self);
1163 #elif __OpenBSD__
1164 retval = syscall(SYS_getthrid);
1165 #elif __NetBSD__
1166 retval = (pid_t) syscall(SYS__lwp_self);
1167 #endif
1169 if (retval == -1) {
1170 return getpid();
1171 }
1172 }
1174 intx os::current_thread_id() {
1175 #ifdef __APPLE__
1176 return (intx)::pthread_mach_thread_np(::pthread_self());
1177 #else
1178 return (intx)::pthread_self();
1179 #endif
1180 }
1182 int os::current_process_id() {
1184 // Under the old bsd thread library, bsd gives each thread
1185 // its own process id. Because of this each thread will return
1186 // a different pid if this method were to return the result
1187 // of getpid(2). Bsd provides no api that returns the pid
1188 // of the launcher thread for the vm. This implementation
1189 // returns a unique pid, the pid of the launcher thread
1190 // that starts the vm 'process'.
1192 // Under the NPTL, getpid() returns the same pid as the
1193 // launcher thread rather than a unique pid per thread.
1194 // Use gettid() if you want the old pre NPTL behaviour.
1196 // if you are looking for the result of a call to getpid() that
1197 // returns a unique pid for the calling thread, then look at the
1198 // OSThread::thread_id() method in osThread_bsd.hpp file
1200 return (int)(_initial_pid ? _initial_pid : getpid());
1201 }
1203 // DLL functions
1205 #define JNI_LIB_PREFIX "lib"
1206 #ifdef __APPLE__
1207 #define JNI_LIB_SUFFIX ".dylib"
1208 #else
1209 #define JNI_LIB_SUFFIX ".so"
1210 #endif
1212 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1214 // This must be hard coded because it's the system's temporary
1215 // directory not the java application's temp directory, ala java.io.tmpdir.
1216 #ifdef __APPLE__
1217 // macosx has a secure per-user temporary directory
1218 char temp_path_storage[PATH_MAX];
1219 const char* os::get_temp_directory() {
1220 static char *temp_path = NULL;
1221 if (temp_path == NULL) {
1222 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1223 if (pathSize == 0 || pathSize > PATH_MAX) {
1224 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1225 }
1226 temp_path = temp_path_storage;
1227 }
1228 return temp_path;
1229 }
1230 #else /* __APPLE__ */
1231 const char* os::get_temp_directory() { return "/tmp"; }
1232 #endif /* __APPLE__ */
1234 static bool file_exists(const char* filename) {
1235 struct stat statbuf;
1236 if (filename == NULL || strlen(filename) == 0) {
1237 return false;
1238 }
1239 return os::stat(filename, &statbuf) == 0;
1240 }
1242 bool os::dll_build_name(char* buffer, size_t buflen,
1243 const char* pname, const char* fname) {
1244 bool retval = false;
1245 // Copied from libhpi
1246 const size_t pnamelen = pname ? strlen(pname) : 0;
1248 // Return error on buffer overflow.
1249 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1250 return retval;
1251 }
1253 if (pnamelen == 0) {
1254 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1255 retval = true;
1256 } else if (strchr(pname, *os::path_separator()) != NULL) {
1257 int n;
1258 char** pelements = split_path(pname, &n);
1259 if (pelements == NULL) {
1260 return false;
1261 }
1262 for (int i = 0 ; i < n ; i++) {
1263 // Really shouldn't be NULL, but check can't hurt
1264 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1265 continue; // skip the empty path values
1266 }
1267 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1268 pelements[i], fname);
1269 if (file_exists(buffer)) {
1270 retval = true;
1271 break;
1272 }
1273 }
1274 // release the storage
1275 for (int i = 0 ; i < n ; i++) {
1276 if (pelements[i] != NULL) {
1277 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1278 }
1279 }
1280 if (pelements != NULL) {
1281 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1282 }
1283 } else {
1284 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1285 retval = true;
1286 }
1287 return retval;
1288 }
1290 // check if addr is inside libjvm.so
1291 bool os::address_is_in_vm(address addr) {
1292 static address libjvm_base_addr;
1293 Dl_info dlinfo;
1295 if (libjvm_base_addr == NULL) {
1296 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1297 libjvm_base_addr = (address)dlinfo.dli_fbase;
1298 }
1299 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1300 }
1302 if (dladdr((void *)addr, &dlinfo) != 0) {
1303 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1304 }
1306 return false;
1307 }
1310 #define MACH_MAXSYMLEN 256
1312 bool os::dll_address_to_function_name(address addr, char *buf,
1313 int buflen, int *offset) {
1314 // buf is not optional, but offset is optional
1315 assert(buf != NULL, "sanity check");
1317 Dl_info dlinfo;
1318 char localbuf[MACH_MAXSYMLEN];
1320 if (dladdr((void*)addr, &dlinfo) != 0) {
1321 // see if we have a matching symbol
1322 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1323 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1324 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1325 }
1326 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1327 return true;
1328 }
1329 // no matching symbol so try for just file info
1330 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1331 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1332 buf, buflen, offset, dlinfo.dli_fname)) {
1333 return true;
1334 }
1335 }
1337 // Handle non-dynamic manually:
1338 if (dlinfo.dli_fbase != NULL &&
1339 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1340 dlinfo.dli_fbase)) {
1341 if (!Decoder::demangle(localbuf, buf, buflen)) {
1342 jio_snprintf(buf, buflen, "%s", localbuf);
1343 }
1344 return true;
1345 }
1346 }
1347 buf[0] = '\0';
1348 if (offset != NULL) *offset = -1;
1349 return false;
1350 }
1352 // ported from solaris version
1353 bool os::dll_address_to_library_name(address addr, char* buf,
1354 int buflen, int* offset) {
1355 // buf is not optional, but offset is optional
1356 assert(buf != NULL, "sanity check");
1358 Dl_info dlinfo;
1360 if (dladdr((void*)addr, &dlinfo) != 0) {
1361 if (dlinfo.dli_fname != NULL) {
1362 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1363 }
1364 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1365 *offset = addr - (address)dlinfo.dli_fbase;
1366 }
1367 return true;
1368 }
1370 buf[0] = '\0';
1371 if (offset) *offset = -1;
1372 return false;
1373 }
1375 // Loads .dll/.so and
1376 // in case of error it checks if .dll/.so was built for the
1377 // same architecture as Hotspot is running on
1379 #ifdef __APPLE__
1380 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1381 void * result= ::dlopen(filename, RTLD_LAZY);
1382 if (result != NULL) {
1383 // Successful loading
1384 return result;
1385 }
1387 // Read system error message into ebuf
1388 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1389 ebuf[ebuflen-1]='\0';
1391 return NULL;
1392 }
1393 #else
1394 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1395 {
1396 void * result= ::dlopen(filename, RTLD_LAZY);
1397 if (result != NULL) {
1398 // Successful loading
1399 return result;
1400 }
1402 Elf32_Ehdr elf_head;
1404 // Read system error message into ebuf
1405 // It may or may not be overwritten below
1406 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1407 ebuf[ebuflen-1]='\0';
1408 int diag_msg_max_length=ebuflen-strlen(ebuf);
1409 char* diag_msg_buf=ebuf+strlen(ebuf);
1411 if (diag_msg_max_length==0) {
1412 // No more space in ebuf for additional diagnostics message
1413 return NULL;
1414 }
1417 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1419 if (file_descriptor < 0) {
1420 // Can't open library, report dlerror() message
1421 return NULL;
1422 }
1424 bool failed_to_read_elf_head=
1425 (sizeof(elf_head)!=
1426 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1428 ::close(file_descriptor);
1429 if (failed_to_read_elf_head) {
1430 // file i/o error - report dlerror() msg
1431 return NULL;
1432 }
1434 typedef struct {
1435 Elf32_Half code; // Actual value as defined in elf.h
1436 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1437 char elf_class; // 32 or 64 bit
1438 char endianess; // MSB or LSB
1439 char* name; // String representation
1440 } arch_t;
1442 #ifndef EM_486
1443 #define EM_486 6 /* Intel 80486 */
1444 #endif
1446 #ifndef EM_MIPS_RS3_LE
1447 #define EM_MIPS_RS3_LE 10 /* MIPS */
1448 #endif
1450 #ifndef EM_PPC64
1451 #define EM_PPC64 21 /* PowerPC64 */
1452 #endif
1454 #ifndef EM_S390
1455 #define EM_S390 22 /* IBM System/390 */
1456 #endif
1458 #ifndef EM_IA_64
1459 #define EM_IA_64 50 /* HP/Intel IA-64 */
1460 #endif
1462 #ifndef EM_X86_64
1463 #define EM_X86_64 62 /* AMD x86-64 */
1464 #endif
1466 static const arch_t arch_array[]={
1467 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1468 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1469 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1470 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1471 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1472 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1473 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1474 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1475 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1476 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1477 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1478 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1479 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1480 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1481 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1482 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1483 };
1485 #if (defined IA32)
1486 static Elf32_Half running_arch_code=EM_386;
1487 #elif (defined AMD64)
1488 static Elf32_Half running_arch_code=EM_X86_64;
1489 #elif (defined IA64)
1490 static Elf32_Half running_arch_code=EM_IA_64;
1491 #elif (defined __sparc) && (defined _LP64)
1492 static Elf32_Half running_arch_code=EM_SPARCV9;
1493 #elif (defined __sparc) && (!defined _LP64)
1494 static Elf32_Half running_arch_code=EM_SPARC;
1495 #elif (defined __powerpc64__)
1496 static Elf32_Half running_arch_code=EM_PPC64;
1497 #elif (defined __powerpc__)
1498 static Elf32_Half running_arch_code=EM_PPC;
1499 #elif (defined ARM)
1500 static Elf32_Half running_arch_code=EM_ARM;
1501 #elif (defined S390)
1502 static Elf32_Half running_arch_code=EM_S390;
1503 #elif (defined ALPHA)
1504 static Elf32_Half running_arch_code=EM_ALPHA;
1505 #elif (defined MIPSEL)
1506 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1507 #elif (defined PARISC)
1508 static Elf32_Half running_arch_code=EM_PARISC;
1509 #elif (defined MIPS)
1510 static Elf32_Half running_arch_code=EM_MIPS;
1511 #elif (defined M68K)
1512 static Elf32_Half running_arch_code=EM_68K;
1513 #else
1514 #error Method os::dll_load requires that one of following is defined:\
1515 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1516 #endif
1518 // Identify compatability class for VM's architecture and library's architecture
1519 // Obtain string descriptions for architectures
1521 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1522 int running_arch_index=-1;
1524 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1525 if (running_arch_code == arch_array[i].code) {
1526 running_arch_index = i;
1527 }
1528 if (lib_arch.code == arch_array[i].code) {
1529 lib_arch.compat_class = arch_array[i].compat_class;
1530 lib_arch.name = arch_array[i].name;
1531 }
1532 }
1534 assert(running_arch_index != -1,
1535 "Didn't find running architecture code (running_arch_code) in arch_array");
1536 if (running_arch_index == -1) {
1537 // Even though running architecture detection failed
1538 // we may still continue with reporting dlerror() message
1539 return NULL;
1540 }
1542 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1543 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1544 return NULL;
1545 }
1547 #ifndef S390
1548 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1550 return NULL;
1551 }
1552 #endif // !S390
1554 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1555 if ( lib_arch.name!=NULL ) {
1556 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1557 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1558 lib_arch.name, arch_array[running_arch_index].name);
1559 } else {
1560 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1561 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1562 lib_arch.code,
1563 arch_array[running_arch_index].name);
1564 }
1565 }
1567 return NULL;
1568 }
1569 #endif /* !__APPLE__ */
1571 void* os::get_default_process_handle() {
1572 #ifdef __APPLE__
1573 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1574 // to avoid finding unexpected symbols on second (or later)
1575 // loads of a library.
1576 return (void*)::dlopen(NULL, RTLD_FIRST);
1577 #else
1578 return (void*)::dlopen(NULL, RTLD_LAZY);
1579 #endif
1580 }
1582 // XXX: Do we need a lock around this as per Linux?
1583 void* os::dll_lookup(void* handle, const char* name) {
1584 return dlsym(handle, name);
1585 }
1588 static bool _print_ascii_file(const char* filename, outputStream* st) {
1589 int fd = ::open(filename, O_RDONLY);
1590 if (fd == -1) {
1591 return false;
1592 }
1594 char buf[32];
1595 int bytes;
1596 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1597 st->print_raw(buf, bytes);
1598 }
1600 ::close(fd);
1602 return true;
1603 }
1605 void os::print_dll_info(outputStream *st) {
1606 st->print_cr("Dynamic libraries:");
1607 #ifdef RTLD_DI_LINKMAP
1608 Dl_info dli;
1609 void *handle;
1610 Link_map *map;
1611 Link_map *p;
1613 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1614 dli.dli_fname == NULL) {
1615 st->print_cr("Error: Cannot print dynamic libraries.");
1616 return;
1617 }
1618 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1619 if (handle == NULL) {
1620 st->print_cr("Error: Cannot print dynamic libraries.");
1621 return;
1622 }
1623 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1624 if (map == NULL) {
1625 st->print_cr("Error: Cannot print dynamic libraries.");
1626 return;
1627 }
1629 while (map->l_prev != NULL)
1630 map = map->l_prev;
1632 while (map != NULL) {
1633 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1634 map = map->l_next;
1635 }
1637 dlclose(handle);
1638 #elif defined(__APPLE__)
1639 uint32_t count;
1640 uint32_t i;
1642 count = _dyld_image_count();
1643 for (i = 1; i < count; i++) {
1644 const char *name = _dyld_get_image_name(i);
1645 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1646 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1647 }
1648 #else
1649 st->print_cr("Error: Cannot print dynamic libraries.");
1650 #endif
1651 }
1653 void os::print_os_info_brief(outputStream* st) {
1654 st->print("Bsd");
1656 os::Posix::print_uname_info(st);
1657 }
1659 void os::print_os_info(outputStream* st) {
1660 st->print("OS:");
1661 st->print("Bsd");
1663 os::Posix::print_uname_info(st);
1665 os::Posix::print_rlimit_info(st);
1667 os::Posix::print_load_average(st);
1668 }
1670 void os::pd_print_cpu_info(outputStream* st) {
1671 // Nothing to do for now.
1672 }
1674 void os::print_memory_info(outputStream* st) {
1676 st->print("Memory:");
1677 st->print(" %dk page", os::vm_page_size()>>10);
1679 st->print(", physical " UINT64_FORMAT "k",
1680 os::physical_memory() >> 10);
1681 st->print("(" UINT64_FORMAT "k free)",
1682 os::available_memory() >> 10);
1683 st->cr();
1685 // meminfo
1686 st->print("\n/proc/meminfo:\n");
1687 _print_ascii_file("/proc/meminfo", st);
1688 st->cr();
1689 }
1691 void os::print_siginfo(outputStream* st, void* siginfo) {
1692 const siginfo_t* si = (const siginfo_t*)siginfo;
1694 os::Posix::print_siginfo_brief(st, si);
1696 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1697 UseSharedSpaces) {
1698 FileMapInfo* mapinfo = FileMapInfo::current_info();
1699 if (mapinfo->is_in_shared_space(si->si_addr)) {
1700 st->print("\n\nError accessing class data sharing archive." \
1701 " Mapped file inaccessible during execution, " \
1702 " possible disk/network problem.");
1703 }
1704 }
1705 st->cr();
1706 }
1709 static void print_signal_handler(outputStream* st, int sig,
1710 char* buf, size_t buflen);
1712 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1713 st->print_cr("Signal Handlers:");
1714 print_signal_handler(st, SIGSEGV, buf, buflen);
1715 print_signal_handler(st, SIGBUS , buf, buflen);
1716 print_signal_handler(st, SIGFPE , buf, buflen);
1717 print_signal_handler(st, SIGPIPE, buf, buflen);
1718 print_signal_handler(st, SIGXFSZ, buf, buflen);
1719 print_signal_handler(st, SIGILL , buf, buflen);
1720 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1721 print_signal_handler(st, SR_signum, buf, buflen);
1722 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1723 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1724 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1725 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1726 }
1728 static char saved_jvm_path[MAXPATHLEN] = {0};
1730 // Find the full path to the current module, libjvm
1731 void os::jvm_path(char *buf, jint buflen) {
1732 // Error checking.
1733 if (buflen < MAXPATHLEN) {
1734 assert(false, "must use a large-enough buffer");
1735 buf[0] = '\0';
1736 return;
1737 }
1738 // Lazy resolve the path to current module.
1739 if (saved_jvm_path[0] != 0) {
1740 strcpy(buf, saved_jvm_path);
1741 return;
1742 }
1744 char dli_fname[MAXPATHLEN];
1745 bool ret = dll_address_to_library_name(
1746 CAST_FROM_FN_PTR(address, os::jvm_path),
1747 dli_fname, sizeof(dli_fname), NULL);
1748 assert(ret, "cannot locate libjvm");
1749 char *rp = NULL;
1750 if (ret && dli_fname[0] != '\0') {
1751 rp = realpath(dli_fname, buf);
1752 }
1753 if (rp == NULL)
1754 return;
1756 if (Arguments::created_by_gamma_launcher()) {
1757 // Support for the gamma launcher. Typical value for buf is
1758 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1759 // the right place in the string, then assume we are installed in a JDK and
1760 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1761 // construct a path to the JVM being overridden.
1763 const char *p = buf + strlen(buf) - 1;
1764 for (int count = 0; p > buf && count < 5; ++count) {
1765 for (--p; p > buf && *p != '/'; --p)
1766 /* empty */ ;
1767 }
1769 if (strncmp(p, "/jre/lib/", 9) != 0) {
1770 // Look for JAVA_HOME in the environment.
1771 char* java_home_var = ::getenv("JAVA_HOME");
1772 if (java_home_var != NULL && java_home_var[0] != 0) {
1773 char* jrelib_p;
1774 int len;
1776 // Check the current module name "libjvm"
1777 p = strrchr(buf, '/');
1778 assert(strstr(p, "/libjvm") == p, "invalid library name");
1780 rp = realpath(java_home_var, buf);
1781 if (rp == NULL)
1782 return;
1784 // determine if this is a legacy image or modules image
1785 // modules image doesn't have "jre" subdirectory
1786 len = strlen(buf);
1787 jrelib_p = buf + len;
1789 // Add the appropriate library subdir
1790 snprintf(jrelib_p, buflen-len, "/jre/lib");
1791 if (0 != access(buf, F_OK)) {
1792 snprintf(jrelib_p, buflen-len, "/lib");
1793 }
1795 // Add the appropriate client or server subdir
1796 len = strlen(buf);
1797 jrelib_p = buf + len;
1798 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1799 if (0 != access(buf, F_OK)) {
1800 snprintf(jrelib_p, buflen-len, "");
1801 }
1803 // If the path exists within JAVA_HOME, add the JVM library name
1804 // to complete the path to JVM being overridden. Otherwise fallback
1805 // to the path to the current library.
1806 if (0 == access(buf, F_OK)) {
1807 // Use current module name "libjvm"
1808 len = strlen(buf);
1809 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1810 } else {
1811 // Fall back to path of current library
1812 rp = realpath(dli_fname, buf);
1813 if (rp == NULL)
1814 return;
1815 }
1816 }
1817 }
1818 }
1820 strcpy(saved_jvm_path, buf);
1821 }
1823 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1824 // no prefix required, not even "_"
1825 }
1827 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1828 // no suffix required
1829 }
1831 ////////////////////////////////////////////////////////////////////////////////
1832 // sun.misc.Signal support
1834 static volatile jint sigint_count = 0;
1836 static void
1837 UserHandler(int sig, void *siginfo, void *context) {
1838 // 4511530 - sem_post is serialized and handled by the manager thread. When
1839 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1840 // don't want to flood the manager thread with sem_post requests.
1841 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1842 return;
1844 // Ctrl-C is pressed during error reporting, likely because the error
1845 // handler fails to abort. Let VM die immediately.
1846 if (sig == SIGINT && is_error_reported()) {
1847 os::die();
1848 }
1850 os::signal_notify(sig);
1851 }
1853 void* os::user_handler() {
1854 return CAST_FROM_FN_PTR(void*, UserHandler);
1855 }
1857 extern "C" {
1858 typedef void (*sa_handler_t)(int);
1859 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1860 }
1862 void* os::signal(int signal_number, void* handler) {
1863 struct sigaction sigAct, oldSigAct;
1865 sigfillset(&(sigAct.sa_mask));
1866 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1867 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1869 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1870 // -1 means registration failed
1871 return (void *)-1;
1872 }
1874 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1875 }
1877 void os::signal_raise(int signal_number) {
1878 ::raise(signal_number);
1879 }
1881 /*
1882 * The following code is moved from os.cpp for making this
1883 * code platform specific, which it is by its very nature.
1884 */
1886 // Will be modified when max signal is changed to be dynamic
1887 int os::sigexitnum_pd() {
1888 return NSIG;
1889 }
1891 // a counter for each possible signal value
1892 static volatile jint pending_signals[NSIG+1] = { 0 };
1894 // Bsd(POSIX) specific hand shaking semaphore.
1895 #ifdef __APPLE__
1896 typedef semaphore_t os_semaphore_t;
1897 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1898 #define SEM_WAIT(sem) semaphore_wait(sem)
1899 #define SEM_POST(sem) semaphore_signal(sem)
1900 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1901 #else
1902 typedef sem_t os_semaphore_t;
1903 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1904 #define SEM_WAIT(sem) sem_wait(&sem)
1905 #define SEM_POST(sem) sem_post(&sem)
1906 #define SEM_DESTROY(sem) sem_destroy(&sem)
1907 #endif
1909 class Semaphore : public StackObj {
1910 public:
1911 Semaphore();
1912 ~Semaphore();
1913 void signal();
1914 void wait();
1915 bool trywait();
1916 bool timedwait(unsigned int sec, int nsec);
1917 private:
1918 jlong currenttime() const;
1919 os_semaphore_t _semaphore;
1920 };
1922 Semaphore::Semaphore() : _semaphore(0) {
1923 SEM_INIT(_semaphore, 0);
1924 }
1926 Semaphore::~Semaphore() {
1927 SEM_DESTROY(_semaphore);
1928 }
1930 void Semaphore::signal() {
1931 SEM_POST(_semaphore);
1932 }
1934 void Semaphore::wait() {
1935 SEM_WAIT(_semaphore);
1936 }
1938 jlong Semaphore::currenttime() const {
1939 struct timeval tv;
1940 gettimeofday(&tv, NULL);
1941 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1942 }
1944 #ifdef __APPLE__
1945 bool Semaphore::trywait() {
1946 return timedwait(0, 0);
1947 }
1949 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1950 kern_return_t kr = KERN_ABORTED;
1951 mach_timespec_t waitspec;
1952 waitspec.tv_sec = sec;
1953 waitspec.tv_nsec = nsec;
1955 jlong starttime = currenttime();
1957 kr = semaphore_timedwait(_semaphore, waitspec);
1958 while (kr == KERN_ABORTED) {
1959 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1961 jlong current = currenttime();
1962 jlong passedtime = current - starttime;
1964 if (passedtime >= totalwait) {
1965 waitspec.tv_sec = 0;
1966 waitspec.tv_nsec = 0;
1967 } else {
1968 jlong waittime = totalwait - (current - starttime);
1969 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1970 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1971 }
1973 kr = semaphore_timedwait(_semaphore, waitspec);
1974 }
1976 return kr == KERN_SUCCESS;
1977 }
1979 #else
1981 bool Semaphore::trywait() {
1982 return sem_trywait(&_semaphore) == 0;
1983 }
1985 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1986 struct timespec ts;
1987 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1989 while (1) {
1990 int result = sem_timedwait(&_semaphore, &ts);
1991 if (result == 0) {
1992 return true;
1993 } else if (errno == EINTR) {
1994 continue;
1995 } else if (errno == ETIMEDOUT) {
1996 return false;
1997 } else {
1998 return false;
1999 }
2000 }
2001 }
2003 #endif // __APPLE__
2005 static os_semaphore_t sig_sem;
2006 static Semaphore sr_semaphore;
2008 void os::signal_init_pd() {
2009 // Initialize signal structures
2010 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2012 // Initialize signal semaphore
2013 ::SEM_INIT(sig_sem, 0);
2014 }
2016 void os::signal_notify(int sig) {
2017 Atomic::inc(&pending_signals[sig]);
2018 ::SEM_POST(sig_sem);
2019 }
2021 static int check_pending_signals(bool wait) {
2022 Atomic::store(0, &sigint_count);
2023 for (;;) {
2024 for (int i = 0; i < NSIG + 1; i++) {
2025 jint n = pending_signals[i];
2026 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2027 return i;
2028 }
2029 }
2030 if (!wait) {
2031 return -1;
2032 }
2033 JavaThread *thread = JavaThread::current();
2034 ThreadBlockInVM tbivm(thread);
2036 bool threadIsSuspended;
2037 do {
2038 thread->set_suspend_equivalent();
2039 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2040 ::SEM_WAIT(sig_sem);
2042 // were we externally suspended while we were waiting?
2043 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2044 if (threadIsSuspended) {
2045 //
2046 // The semaphore has been incremented, but while we were waiting
2047 // another thread suspended us. We don't want to continue running
2048 // while suspended because that would surprise the thread that
2049 // suspended us.
2050 //
2051 ::SEM_POST(sig_sem);
2053 thread->java_suspend_self();
2054 }
2055 } while (threadIsSuspended);
2056 }
2057 }
2059 int os::signal_lookup() {
2060 return check_pending_signals(false);
2061 }
2063 int os::signal_wait() {
2064 return check_pending_signals(true);
2065 }
2067 ////////////////////////////////////////////////////////////////////////////////
2068 // Virtual Memory
2070 int os::vm_page_size() {
2071 // Seems redundant as all get out
2072 assert(os::Bsd::page_size() != -1, "must call os::init");
2073 return os::Bsd::page_size();
2074 }
2076 // Solaris allocates memory by pages.
2077 int os::vm_allocation_granularity() {
2078 assert(os::Bsd::page_size() != -1, "must call os::init");
2079 return os::Bsd::page_size();
2080 }
2082 // Rationale behind this function:
2083 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2084 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2085 // samples for JITted code. Here we create private executable mapping over the code cache
2086 // and then we can use standard (well, almost, as mapping can change) way to provide
2087 // info for the reporting script by storing timestamp and location of symbol
2088 void bsd_wrap_code(char* base, size_t size) {
2089 static volatile jint cnt = 0;
2091 if (!UseOprofile) {
2092 return;
2093 }
2095 char buf[PATH_MAX + 1];
2096 int num = Atomic::add(1, &cnt);
2098 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2099 os::get_temp_directory(), os::current_process_id(), num);
2100 unlink(buf);
2102 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2104 if (fd != -1) {
2105 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2106 if (rv != (off_t)-1) {
2107 if (::write(fd, "", 1) == 1) {
2108 mmap(base, size,
2109 PROT_READ|PROT_WRITE|PROT_EXEC,
2110 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2111 }
2112 }
2113 ::close(fd);
2114 unlink(buf);
2115 }
2116 }
2118 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2119 int err) {
2120 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2121 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2122 strerror(err), err);
2123 }
2125 // NOTE: Bsd kernel does not really reserve the pages for us.
2126 // All it does is to check if there are enough free pages
2127 // left at the time of mmap(). This could be a potential
2128 // problem.
2129 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2130 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2131 #ifdef __OpenBSD__
2132 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2133 if (::mprotect(addr, size, prot) == 0) {
2134 return true;
2135 }
2136 #else
2137 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2138 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2139 if (res != (uintptr_t) MAP_FAILED) {
2140 return true;
2141 }
2142 #endif
2144 // Warn about any commit errors we see in non-product builds just
2145 // in case mmap() doesn't work as described on the man page.
2146 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2148 return false;
2149 }
2151 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2152 bool exec) {
2153 // alignment_hint is ignored on this OS
2154 return pd_commit_memory(addr, size, exec);
2155 }
2157 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2158 const char* mesg) {
2159 assert(mesg != NULL, "mesg must be specified");
2160 if (!pd_commit_memory(addr, size, exec)) {
2161 // add extra info in product mode for vm_exit_out_of_memory():
2162 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2163 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2164 }
2165 }
2167 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2168 size_t alignment_hint, bool exec,
2169 const char* mesg) {
2170 // alignment_hint is ignored on this OS
2171 pd_commit_memory_or_exit(addr, size, exec, mesg);
2172 }
2174 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2175 }
2177 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2178 ::madvise(addr, bytes, MADV_DONTNEED);
2179 }
2181 void os::numa_make_global(char *addr, size_t bytes) {
2182 }
2184 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2185 }
2187 bool os::numa_topology_changed() { return false; }
2189 size_t os::numa_get_groups_num() {
2190 return 1;
2191 }
2193 int os::numa_get_group_id() {
2194 return 0;
2195 }
2197 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2198 if (size > 0) {
2199 ids[0] = 0;
2200 return 1;
2201 }
2202 return 0;
2203 }
2205 bool os::get_page_info(char *start, page_info* info) {
2206 return false;
2207 }
2209 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2210 return end;
2211 }
2214 bool os::pd_uncommit_memory(char* addr, size_t size) {
2215 #ifdef __OpenBSD__
2216 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2217 return ::mprotect(addr, size, PROT_NONE) == 0;
2218 #else
2219 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2220 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2221 return res != (uintptr_t) MAP_FAILED;
2222 #endif
2223 }
2225 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2226 return os::commit_memory(addr, size, !ExecMem);
2227 }
2229 // If this is a growable mapping, remove the guard pages entirely by
2230 // munmap()ping them. If not, just call uncommit_memory().
2231 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2232 return os::uncommit_memory(addr, size);
2233 }
2235 static address _highest_vm_reserved_address = NULL;
2237 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2238 // at 'requested_addr'. If there are existing memory mappings at the same
2239 // location, however, they will be overwritten. If 'fixed' is false,
2240 // 'requested_addr' is only treated as a hint, the return value may or
2241 // may not start from the requested address. Unlike Bsd mmap(), this
2242 // function returns NULL to indicate failure.
2243 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2244 char * addr;
2245 int flags;
2247 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2248 if (fixed) {
2249 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2250 flags |= MAP_FIXED;
2251 }
2253 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2254 // touch an uncommitted page. Otherwise, the read/write might
2255 // succeed if we have enough swap space to back the physical page.
2256 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2257 flags, -1, 0);
2259 if (addr != MAP_FAILED) {
2260 // anon_mmap() should only get called during VM initialization,
2261 // don't need lock (actually we can skip locking even it can be called
2262 // from multiple threads, because _highest_vm_reserved_address is just a
2263 // hint about the upper limit of non-stack memory regions.)
2264 if ((address)addr + bytes > _highest_vm_reserved_address) {
2265 _highest_vm_reserved_address = (address)addr + bytes;
2266 }
2267 }
2269 return addr == MAP_FAILED ? NULL : addr;
2270 }
2272 // Don't update _highest_vm_reserved_address, because there might be memory
2273 // regions above addr + size. If so, releasing a memory region only creates
2274 // a hole in the address space, it doesn't help prevent heap-stack collision.
2275 //
2276 static int anon_munmap(char * addr, size_t size) {
2277 return ::munmap(addr, size) == 0;
2278 }
2280 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2281 size_t alignment_hint) {
2282 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2283 }
2285 bool os::pd_release_memory(char* addr, size_t size) {
2286 return anon_munmap(addr, size);
2287 }
2289 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2290 // Bsd wants the mprotect address argument to be page aligned.
2291 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2293 // According to SUSv3, mprotect() should only be used with mappings
2294 // established by mmap(), and mmap() always maps whole pages. Unaligned
2295 // 'addr' likely indicates problem in the VM (e.g. trying to change
2296 // protection of malloc'ed or statically allocated memory). Check the
2297 // caller if you hit this assert.
2298 assert(addr == bottom, "sanity check");
2300 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2301 return ::mprotect(bottom, size, prot) == 0;
2302 }
2304 // Set protections specified
2305 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2306 bool is_committed) {
2307 unsigned int p = 0;
2308 switch (prot) {
2309 case MEM_PROT_NONE: p = PROT_NONE; break;
2310 case MEM_PROT_READ: p = PROT_READ; break;
2311 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2312 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2313 default:
2314 ShouldNotReachHere();
2315 }
2316 // is_committed is unused.
2317 return bsd_mprotect(addr, bytes, p);
2318 }
2320 bool os::guard_memory(char* addr, size_t size) {
2321 return bsd_mprotect(addr, size, PROT_NONE);
2322 }
2324 bool os::unguard_memory(char* addr, size_t size) {
2325 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2326 }
2328 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2329 return false;
2330 }
2332 // Large page support
2334 static size_t _large_page_size = 0;
2336 void os::large_page_init() {
2337 }
2340 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2341 fatal("This code is not used or maintained.");
2343 // "exec" is passed in but not used. Creating the shared image for
2344 // the code cache doesn't have an SHM_X executable permission to check.
2345 assert(UseLargePages && UseSHM, "only for SHM large pages");
2347 key_t key = IPC_PRIVATE;
2348 char *addr;
2350 bool warn_on_failure = UseLargePages &&
2351 (!FLAG_IS_DEFAULT(UseLargePages) ||
2352 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2353 );
2354 char msg[128];
2356 // Create a large shared memory region to attach to based on size.
2357 // Currently, size is the total size of the heap
2358 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2359 if (shmid == -1) {
2360 // Possible reasons for shmget failure:
2361 // 1. shmmax is too small for Java heap.
2362 // > check shmmax value: cat /proc/sys/kernel/shmmax
2363 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2364 // 2. not enough large page memory.
2365 // > check available large pages: cat /proc/meminfo
2366 // > increase amount of large pages:
2367 // echo new_value > /proc/sys/vm/nr_hugepages
2368 // Note 1: different Bsd may use different name for this property,
2369 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2370 // Note 2: it's possible there's enough physical memory available but
2371 // they are so fragmented after a long run that they can't
2372 // coalesce into large pages. Try to reserve large pages when
2373 // the system is still "fresh".
2374 if (warn_on_failure) {
2375 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2376 warning(msg);
2377 }
2378 return NULL;
2379 }
2381 // attach to the region
2382 addr = (char*)shmat(shmid, req_addr, 0);
2383 int err = errno;
2385 // Remove shmid. If shmat() is successful, the actual shared memory segment
2386 // will be deleted when it's detached by shmdt() or when the process
2387 // terminates. If shmat() is not successful this will remove the shared
2388 // segment immediately.
2389 shmctl(shmid, IPC_RMID, NULL);
2391 if ((intptr_t)addr == -1) {
2392 if (warn_on_failure) {
2393 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2394 warning(msg);
2395 }
2396 return NULL;
2397 }
2399 // The memory is committed
2400 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2402 return addr;
2403 }
2405 bool os::release_memory_special(char* base, size_t bytes) {
2406 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2407 // detaching the SHM segment will also delete it, see reserve_memory_special()
2408 int rslt = shmdt(base);
2409 if (rslt == 0) {
2410 tkr.record((address)base, bytes);
2411 return true;
2412 } else {
2413 tkr.discard();
2414 return false;
2415 }
2417 }
2419 size_t os::large_page_size() {
2420 return _large_page_size;
2421 }
2423 // HugeTLBFS allows application to commit large page memory on demand;
2424 // with SysV SHM the entire memory region must be allocated as shared
2425 // memory.
2426 bool os::can_commit_large_page_memory() {
2427 return UseHugeTLBFS;
2428 }
2430 bool os::can_execute_large_page_memory() {
2431 return UseHugeTLBFS;
2432 }
2434 // Reserve memory at an arbitrary address, only if that area is
2435 // available (and not reserved for something else).
2437 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2438 const int max_tries = 10;
2439 char* base[max_tries];
2440 size_t size[max_tries];
2441 const size_t gap = 0x000000;
2443 // Assert only that the size is a multiple of the page size, since
2444 // that's all that mmap requires, and since that's all we really know
2445 // about at this low abstraction level. If we need higher alignment,
2446 // we can either pass an alignment to this method or verify alignment
2447 // in one of the methods further up the call chain. See bug 5044738.
2448 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2450 // Repeatedly allocate blocks until the block is allocated at the
2451 // right spot. Give up after max_tries. Note that reserve_memory() will
2452 // automatically update _highest_vm_reserved_address if the call is
2453 // successful. The variable tracks the highest memory address every reserved
2454 // by JVM. It is used to detect heap-stack collision if running with
2455 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2456 // space than needed, it could confuse the collision detecting code. To
2457 // solve the problem, save current _highest_vm_reserved_address and
2458 // calculate the correct value before return.
2459 address old_highest = _highest_vm_reserved_address;
2461 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2462 // if kernel honors the hint then we can return immediately.
2463 char * addr = anon_mmap(requested_addr, bytes, false);
2464 if (addr == requested_addr) {
2465 return requested_addr;
2466 }
2468 if (addr != NULL) {
2469 // mmap() is successful but it fails to reserve at the requested address
2470 anon_munmap(addr, bytes);
2471 }
2473 int i;
2474 for (i = 0; i < max_tries; ++i) {
2475 base[i] = reserve_memory(bytes);
2477 if (base[i] != NULL) {
2478 // Is this the block we wanted?
2479 if (base[i] == requested_addr) {
2480 size[i] = bytes;
2481 break;
2482 }
2484 // Does this overlap the block we wanted? Give back the overlapped
2485 // parts and try again.
2487 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2488 if (top_overlap >= 0 && top_overlap < bytes) {
2489 unmap_memory(base[i], top_overlap);
2490 base[i] += top_overlap;
2491 size[i] = bytes - top_overlap;
2492 } else {
2493 size_t bottom_overlap = base[i] + bytes - requested_addr;
2494 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2495 unmap_memory(requested_addr, bottom_overlap);
2496 size[i] = bytes - bottom_overlap;
2497 } else {
2498 size[i] = bytes;
2499 }
2500 }
2501 }
2502 }
2504 // Give back the unused reserved pieces.
2506 for (int j = 0; j < i; ++j) {
2507 if (base[j] != NULL) {
2508 unmap_memory(base[j], size[j]);
2509 }
2510 }
2512 if (i < max_tries) {
2513 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2514 return requested_addr;
2515 } else {
2516 _highest_vm_reserved_address = old_highest;
2517 return NULL;
2518 }
2519 }
2521 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2522 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2523 }
2525 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2526 // Solaris uses poll(), bsd uses park().
2527 // Poll() is likely a better choice, assuming that Thread.interrupt()
2528 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2529 // SIGSEGV, see 4355769.
2531 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2532 assert(thread == Thread::current(), "thread consistency check");
2534 ParkEvent * const slp = thread->_SleepEvent ;
2535 slp->reset() ;
2536 OrderAccess::fence() ;
2538 if (interruptible) {
2539 jlong prevtime = javaTimeNanos();
2541 for (;;) {
2542 if (os::is_interrupted(thread, true)) {
2543 return OS_INTRPT;
2544 }
2546 jlong newtime = javaTimeNanos();
2548 if (newtime - prevtime < 0) {
2549 // time moving backwards, should only happen if no monotonic clock
2550 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2551 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2552 } else {
2553 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2554 }
2556 if(millis <= 0) {
2557 return OS_OK;
2558 }
2560 prevtime = newtime;
2562 {
2563 assert(thread->is_Java_thread(), "sanity check");
2564 JavaThread *jt = (JavaThread *) thread;
2565 ThreadBlockInVM tbivm(jt);
2566 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2568 jt->set_suspend_equivalent();
2569 // cleared by handle_special_suspend_equivalent_condition() or
2570 // java_suspend_self() via check_and_wait_while_suspended()
2572 slp->park(millis);
2574 // were we externally suspended while we were waiting?
2575 jt->check_and_wait_while_suspended();
2576 }
2577 }
2578 } else {
2579 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2580 jlong prevtime = javaTimeNanos();
2582 for (;;) {
2583 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2584 // the 1st iteration ...
2585 jlong newtime = javaTimeNanos();
2587 if (newtime - prevtime < 0) {
2588 // time moving backwards, should only happen if no monotonic clock
2589 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2590 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2591 } else {
2592 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2593 }
2595 if(millis <= 0) break ;
2597 prevtime = newtime;
2598 slp->park(millis);
2599 }
2600 return OS_OK ;
2601 }
2602 }
2604 void os::naked_short_sleep(jlong ms) {
2605 struct timespec req;
2607 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2608 req.tv_sec = 0;
2609 if (ms > 0) {
2610 req.tv_nsec = (ms % 1000) * 1000000;
2611 }
2612 else {
2613 req.tv_nsec = 1;
2614 }
2616 nanosleep(&req, NULL);
2618 return;
2619 }
2621 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2622 void os::infinite_sleep() {
2623 while (true) { // sleep forever ...
2624 ::sleep(100); // ... 100 seconds at a time
2625 }
2626 }
2628 // Used to convert frequent JVM_Yield() to nops
2629 bool os::dont_yield() {
2630 return DontYieldALot;
2631 }
2633 void os::yield() {
2634 sched_yield();
2635 }
2637 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2639 void os::yield_all(int attempts) {
2640 // Yields to all threads, including threads with lower priorities
2641 // Threads on Bsd are all with same priority. The Solaris style
2642 // os::yield_all() with nanosleep(1ms) is not necessary.
2643 sched_yield();
2644 }
2646 // Called from the tight loops to possibly influence time-sharing heuristics
2647 void os::loop_breaker(int attempts) {
2648 os::yield_all(attempts);
2649 }
2651 ////////////////////////////////////////////////////////////////////////////////
2652 // thread priority support
2654 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2655 // only supports dynamic priority, static priority must be zero. For real-time
2656 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2657 // However, for large multi-threaded applications, SCHED_RR is not only slower
2658 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2659 // of 5 runs - Sep 2005).
2660 //
2661 // The following code actually changes the niceness of kernel-thread/LWP. It
2662 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2663 // not the entire user process, and user level threads are 1:1 mapped to kernel
2664 // threads. It has always been the case, but could change in the future. For
2665 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2666 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2668 #if !defined(__APPLE__)
2669 int os::java_to_os_priority[CriticalPriority + 1] = {
2670 19, // 0 Entry should never be used
2672 0, // 1 MinPriority
2673 3, // 2
2674 6, // 3
2676 10, // 4
2677 15, // 5 NormPriority
2678 18, // 6
2680 21, // 7
2681 25, // 8
2682 28, // 9 NearMaxPriority
2684 31, // 10 MaxPriority
2686 31 // 11 CriticalPriority
2687 };
2688 #else
2689 /* Using Mach high-level priority assignments */
2690 int os::java_to_os_priority[CriticalPriority + 1] = {
2691 0, // 0 Entry should never be used (MINPRI_USER)
2693 27, // 1 MinPriority
2694 28, // 2
2695 29, // 3
2697 30, // 4
2698 31, // 5 NormPriority (BASEPRI_DEFAULT)
2699 32, // 6
2701 33, // 7
2702 34, // 8
2703 35, // 9 NearMaxPriority
2705 36, // 10 MaxPriority
2707 36 // 11 CriticalPriority
2708 };
2709 #endif
2711 static int prio_init() {
2712 if (ThreadPriorityPolicy == 1) {
2713 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2714 // if effective uid is not root. Perhaps, a more elegant way of doing
2715 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2716 if (geteuid() != 0) {
2717 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2718 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2719 }
2720 ThreadPriorityPolicy = 0;
2721 }
2722 }
2723 if (UseCriticalJavaThreadPriority) {
2724 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2725 }
2726 return 0;
2727 }
2729 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2730 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2732 #ifdef __OpenBSD__
2733 // OpenBSD pthread_setprio starves low priority threads
2734 return OS_OK;
2735 #elif defined(__FreeBSD__)
2736 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2737 #elif defined(__APPLE__) || defined(__NetBSD__)
2738 struct sched_param sp;
2739 int policy;
2740 pthread_t self = pthread_self();
2742 if (pthread_getschedparam(self, &policy, &sp) != 0)
2743 return OS_ERR;
2745 sp.sched_priority = newpri;
2746 if (pthread_setschedparam(self, policy, &sp) != 0)
2747 return OS_ERR;
2749 return OS_OK;
2750 #else
2751 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2752 return (ret == 0) ? OS_OK : OS_ERR;
2753 #endif
2754 }
2756 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2757 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2758 *priority_ptr = java_to_os_priority[NormPriority];
2759 return OS_OK;
2760 }
2762 errno = 0;
2763 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2764 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2765 #elif defined(__APPLE__) || defined(__NetBSD__)
2766 int policy;
2767 struct sched_param sp;
2769 pthread_getschedparam(pthread_self(), &policy, &sp);
2770 *priority_ptr = sp.sched_priority;
2771 #else
2772 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2773 #endif
2774 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2775 }
2777 // Hint to the underlying OS that a task switch would not be good.
2778 // Void return because it's a hint and can fail.
2779 void os::hint_no_preempt() {}
2781 ////////////////////////////////////////////////////////////////////////////////
2782 // suspend/resume support
2784 // the low-level signal-based suspend/resume support is a remnant from the
2785 // old VM-suspension that used to be for java-suspension, safepoints etc,
2786 // within hotspot. Now there is a single use-case for this:
2787 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2788 // that runs in the watcher thread.
2789 // The remaining code is greatly simplified from the more general suspension
2790 // code that used to be used.
2791 //
2792 // The protocol is quite simple:
2793 // - suspend:
2794 // - sends a signal to the target thread
2795 // - polls the suspend state of the osthread using a yield loop
2796 // - target thread signal handler (SR_handler) sets suspend state
2797 // and blocks in sigsuspend until continued
2798 // - resume:
2799 // - sets target osthread state to continue
2800 // - sends signal to end the sigsuspend loop in the SR_handler
2801 //
2802 // Note that the SR_lock plays no role in this suspend/resume protocol.
2803 //
2805 static void resume_clear_context(OSThread *osthread) {
2806 osthread->set_ucontext(NULL);
2807 osthread->set_siginfo(NULL);
2808 }
2810 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2811 osthread->set_ucontext(context);
2812 osthread->set_siginfo(siginfo);
2813 }
2815 //
2816 // Handler function invoked when a thread's execution is suspended or
2817 // resumed. We have to be careful that only async-safe functions are
2818 // called here (Note: most pthread functions are not async safe and
2819 // should be avoided.)
2820 //
2821 // Note: sigwait() is a more natural fit than sigsuspend() from an
2822 // interface point of view, but sigwait() prevents the signal hander
2823 // from being run. libpthread would get very confused by not having
2824 // its signal handlers run and prevents sigwait()'s use with the
2825 // mutex granting granting signal.
2826 //
2827 // Currently only ever called on the VMThread or JavaThread
2828 //
2829 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2830 // Save and restore errno to avoid confusing native code with EINTR
2831 // after sigsuspend.
2832 int old_errno = errno;
2834 Thread* thread = Thread::current();
2835 OSThread* osthread = thread->osthread();
2836 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2838 os::SuspendResume::State current = osthread->sr.state();
2839 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2840 suspend_save_context(osthread, siginfo, context);
2842 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2843 os::SuspendResume::State state = osthread->sr.suspended();
2844 if (state == os::SuspendResume::SR_SUSPENDED) {
2845 sigset_t suspend_set; // signals for sigsuspend()
2847 // get current set of blocked signals and unblock resume signal
2848 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2849 sigdelset(&suspend_set, SR_signum);
2851 sr_semaphore.signal();
2852 // wait here until we are resumed
2853 while (1) {
2854 sigsuspend(&suspend_set);
2856 os::SuspendResume::State result = osthread->sr.running();
2857 if (result == os::SuspendResume::SR_RUNNING) {
2858 sr_semaphore.signal();
2859 break;
2860 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2861 ShouldNotReachHere();
2862 }
2863 }
2865 } else if (state == os::SuspendResume::SR_RUNNING) {
2866 // request was cancelled, continue
2867 } else {
2868 ShouldNotReachHere();
2869 }
2871 resume_clear_context(osthread);
2872 } else if (current == os::SuspendResume::SR_RUNNING) {
2873 // request was cancelled, continue
2874 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2875 // ignore
2876 } else {
2877 // ignore
2878 }
2880 errno = old_errno;
2881 }
2884 static int SR_initialize() {
2885 struct sigaction act;
2886 char *s;
2887 /* Get signal number to use for suspend/resume */
2888 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2889 int sig = ::strtol(s, 0, 10);
2890 if (sig > 0 || sig < NSIG) {
2891 SR_signum = sig;
2892 }
2893 }
2895 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2896 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2898 sigemptyset(&SR_sigset);
2899 sigaddset(&SR_sigset, SR_signum);
2901 /* Set up signal handler for suspend/resume */
2902 act.sa_flags = SA_RESTART|SA_SIGINFO;
2903 act.sa_handler = (void (*)(int)) SR_handler;
2905 // SR_signum is blocked by default.
2906 // 4528190 - We also need to block pthread restart signal (32 on all
2907 // supported Bsd platforms). Note that BsdThreads need to block
2908 // this signal for all threads to work properly. So we don't have
2909 // to use hard-coded signal number when setting up the mask.
2910 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2912 if (sigaction(SR_signum, &act, 0) == -1) {
2913 return -1;
2914 }
2916 // Save signal flag
2917 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2918 return 0;
2919 }
2921 static int sr_notify(OSThread* osthread) {
2922 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2923 assert_status(status == 0, status, "pthread_kill");
2924 return status;
2925 }
2927 // "Randomly" selected value for how long we want to spin
2928 // before bailing out on suspending a thread, also how often
2929 // we send a signal to a thread we want to resume
2930 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2931 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2933 // returns true on success and false on error - really an error is fatal
2934 // but this seems the normal response to library errors
2935 static bool do_suspend(OSThread* osthread) {
2936 assert(osthread->sr.is_running(), "thread should be running");
2937 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2939 // mark as suspended and send signal
2940 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2941 // failed to switch, state wasn't running?
2942 ShouldNotReachHere();
2943 return false;
2944 }
2946 if (sr_notify(osthread) != 0) {
2947 ShouldNotReachHere();
2948 }
2950 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2951 while (true) {
2952 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2953 break;
2954 } else {
2955 // timeout
2956 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2957 if (cancelled == os::SuspendResume::SR_RUNNING) {
2958 return false;
2959 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2960 // make sure that we consume the signal on the semaphore as well
2961 sr_semaphore.wait();
2962 break;
2963 } else {
2964 ShouldNotReachHere();
2965 return false;
2966 }
2967 }
2968 }
2970 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2971 return true;
2972 }
2974 static void do_resume(OSThread* osthread) {
2975 assert(osthread->sr.is_suspended(), "thread should be suspended");
2976 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2978 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2979 // failed to switch to WAKEUP_REQUEST
2980 ShouldNotReachHere();
2981 return;
2982 }
2984 while (true) {
2985 if (sr_notify(osthread) == 0) {
2986 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2987 if (osthread->sr.is_running()) {
2988 return;
2989 }
2990 }
2991 } else {
2992 ShouldNotReachHere();
2993 }
2994 }
2996 guarantee(osthread->sr.is_running(), "Must be running!");
2997 }
2999 ////////////////////////////////////////////////////////////////////////////////
3000 // interrupt support
3002 void os::interrupt(Thread* thread) {
3003 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3004 "possibility of dangling Thread pointer");
3006 OSThread* osthread = thread->osthread();
3008 if (!osthread->interrupted()) {
3009 osthread->set_interrupted(true);
3010 // More than one thread can get here with the same value of osthread,
3011 // resulting in multiple notifications. We do, however, want the store
3012 // to interrupted() to be visible to other threads before we execute unpark().
3013 OrderAccess::fence();
3014 ParkEvent * const slp = thread->_SleepEvent ;
3015 if (slp != NULL) slp->unpark() ;
3016 }
3018 // For JSR166. Unpark even if interrupt status already was set
3019 if (thread->is_Java_thread())
3020 ((JavaThread*)thread)->parker()->unpark();
3022 ParkEvent * ev = thread->_ParkEvent ;
3023 if (ev != NULL) ev->unpark() ;
3025 }
3027 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3028 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3029 "possibility of dangling Thread pointer");
3031 OSThread* osthread = thread->osthread();
3033 bool interrupted = osthread->interrupted();
3035 if (interrupted && clear_interrupted) {
3036 osthread->set_interrupted(false);
3037 // consider thread->_SleepEvent->reset() ... optional optimization
3038 }
3040 return interrupted;
3041 }
3043 ///////////////////////////////////////////////////////////////////////////////////
3044 // signal handling (except suspend/resume)
3046 // This routine may be used by user applications as a "hook" to catch signals.
3047 // The user-defined signal handler must pass unrecognized signals to this
3048 // routine, and if it returns true (non-zero), then the signal handler must
3049 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3050 // routine will never retun false (zero), but instead will execute a VM panic
3051 // routine kill the process.
3052 //
3053 // If this routine returns false, it is OK to call it again. This allows
3054 // the user-defined signal handler to perform checks either before or after
3055 // the VM performs its own checks. Naturally, the user code would be making
3056 // a serious error if it tried to handle an exception (such as a null check
3057 // or breakpoint) that the VM was generating for its own correct operation.
3058 //
3059 // This routine may recognize any of the following kinds of signals:
3060 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3061 // It should be consulted by handlers for any of those signals.
3062 //
3063 // The caller of this routine must pass in the three arguments supplied
3064 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3065 // field of the structure passed to sigaction(). This routine assumes that
3066 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3067 //
3068 // Note that the VM will print warnings if it detects conflicting signal
3069 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3070 //
3071 extern "C" JNIEXPORT int
3072 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3073 void* ucontext, int abort_if_unrecognized);
3075 void signalHandler(int sig, siginfo_t* info, void* uc) {
3076 assert(info != NULL && uc != NULL, "it must be old kernel");
3077 int orig_errno = errno; // Preserve errno value over signal handler.
3078 JVM_handle_bsd_signal(sig, info, uc, true);
3079 errno = orig_errno;
3080 }
3083 // This boolean allows users to forward their own non-matching signals
3084 // to JVM_handle_bsd_signal, harmlessly.
3085 bool os::Bsd::signal_handlers_are_installed = false;
3087 // For signal-chaining
3088 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3089 unsigned int os::Bsd::sigs = 0;
3090 bool os::Bsd::libjsig_is_loaded = false;
3091 typedef struct sigaction *(*get_signal_t)(int);
3092 get_signal_t os::Bsd::get_signal_action = NULL;
3094 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3095 struct sigaction *actp = NULL;
3097 if (libjsig_is_loaded) {
3098 // Retrieve the old signal handler from libjsig
3099 actp = (*get_signal_action)(sig);
3100 }
3101 if (actp == NULL) {
3102 // Retrieve the preinstalled signal handler from jvm
3103 actp = get_preinstalled_handler(sig);
3104 }
3106 return actp;
3107 }
3109 static bool call_chained_handler(struct sigaction *actp, int sig,
3110 siginfo_t *siginfo, void *context) {
3111 // Call the old signal handler
3112 if (actp->sa_handler == SIG_DFL) {
3113 // It's more reasonable to let jvm treat it as an unexpected exception
3114 // instead of taking the default action.
3115 return false;
3116 } else if (actp->sa_handler != SIG_IGN) {
3117 if ((actp->sa_flags & SA_NODEFER) == 0) {
3118 // automaticlly block the signal
3119 sigaddset(&(actp->sa_mask), sig);
3120 }
3122 sa_handler_t hand;
3123 sa_sigaction_t sa;
3124 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3125 // retrieve the chained handler
3126 if (siginfo_flag_set) {
3127 sa = actp->sa_sigaction;
3128 } else {
3129 hand = actp->sa_handler;
3130 }
3132 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3133 actp->sa_handler = SIG_DFL;
3134 }
3136 // try to honor the signal mask
3137 sigset_t oset;
3138 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3140 // call into the chained handler
3141 if (siginfo_flag_set) {
3142 (*sa)(sig, siginfo, context);
3143 } else {
3144 (*hand)(sig);
3145 }
3147 // restore the signal mask
3148 pthread_sigmask(SIG_SETMASK, &oset, 0);
3149 }
3150 // Tell jvm's signal handler the signal is taken care of.
3151 return true;
3152 }
3154 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3155 bool chained = false;
3156 // signal-chaining
3157 if (UseSignalChaining) {
3158 struct sigaction *actp = get_chained_signal_action(sig);
3159 if (actp != NULL) {
3160 chained = call_chained_handler(actp, sig, siginfo, context);
3161 }
3162 }
3163 return chained;
3164 }
3166 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3167 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3168 return &sigact[sig];
3169 }
3170 return NULL;
3171 }
3173 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3174 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3175 sigact[sig] = oldAct;
3176 sigs |= (unsigned int)1 << sig;
3177 }
3179 // for diagnostic
3180 int os::Bsd::sigflags[MAXSIGNUM];
3182 int os::Bsd::get_our_sigflags(int sig) {
3183 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3184 return sigflags[sig];
3185 }
3187 void os::Bsd::set_our_sigflags(int sig, int flags) {
3188 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3189 sigflags[sig] = flags;
3190 }
3192 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3193 // Check for overwrite.
3194 struct sigaction oldAct;
3195 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3197 void* oldhand = oldAct.sa_sigaction
3198 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3199 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3200 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3201 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3202 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3203 if (AllowUserSignalHandlers || !set_installed) {
3204 // Do not overwrite; user takes responsibility to forward to us.
3205 return;
3206 } else if (UseSignalChaining) {
3207 // save the old handler in jvm
3208 save_preinstalled_handler(sig, oldAct);
3209 // libjsig also interposes the sigaction() call below and saves the
3210 // old sigaction on it own.
3211 } else {
3212 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3213 "%#lx for signal %d.", (long)oldhand, sig));
3214 }
3215 }
3217 struct sigaction sigAct;
3218 sigfillset(&(sigAct.sa_mask));
3219 sigAct.sa_handler = SIG_DFL;
3220 if (!set_installed) {
3221 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3222 } else {
3223 sigAct.sa_sigaction = signalHandler;
3224 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3225 }
3226 #if __APPLE__
3227 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3228 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3229 // if the signal handler declares it will handle it on alternate stack.
3230 // Notice we only declare we will handle it on alt stack, but we are not
3231 // actually going to use real alt stack - this is just a workaround.
3232 // Please see ux_exception.c, method catch_mach_exception_raise for details
3233 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3234 if (sig == SIGSEGV) {
3235 sigAct.sa_flags |= SA_ONSTACK;
3236 }
3237 #endif
3239 // Save flags, which are set by ours
3240 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3241 sigflags[sig] = sigAct.sa_flags;
3243 int ret = sigaction(sig, &sigAct, &oldAct);
3244 assert(ret == 0, "check");
3246 void* oldhand2 = oldAct.sa_sigaction
3247 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3248 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3249 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3250 }
3252 // install signal handlers for signals that HotSpot needs to
3253 // handle in order to support Java-level exception handling.
3255 void os::Bsd::install_signal_handlers() {
3256 if (!signal_handlers_are_installed) {
3257 signal_handlers_are_installed = true;
3259 // signal-chaining
3260 typedef void (*signal_setting_t)();
3261 signal_setting_t begin_signal_setting = NULL;
3262 signal_setting_t end_signal_setting = NULL;
3263 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3264 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3265 if (begin_signal_setting != NULL) {
3266 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3267 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3268 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3269 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3270 libjsig_is_loaded = true;
3271 assert(UseSignalChaining, "should enable signal-chaining");
3272 }
3273 if (libjsig_is_loaded) {
3274 // Tell libjsig jvm is setting signal handlers
3275 (*begin_signal_setting)();
3276 }
3278 set_signal_handler(SIGSEGV, true);
3279 set_signal_handler(SIGPIPE, true);
3280 set_signal_handler(SIGBUS, true);
3281 set_signal_handler(SIGILL, true);
3282 set_signal_handler(SIGFPE, true);
3283 set_signal_handler(SIGXFSZ, true);
3285 #if defined(__APPLE__)
3286 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3287 // signals caught and handled by the JVM. To work around this, we reset the mach task
3288 // signal handler that's placed on our process by CrashReporter. This disables
3289 // CrashReporter-based reporting.
3290 //
3291 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3292 // on caught fatal signals.
3293 //
3294 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3295 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3296 // exception handling, while leaving the standard BSD signal handlers functional.
3297 kern_return_t kr;
3298 kr = task_set_exception_ports(mach_task_self(),
3299 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3300 MACH_PORT_NULL,
3301 EXCEPTION_STATE_IDENTITY,
3302 MACHINE_THREAD_STATE);
3304 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3305 #endif
3307 if (libjsig_is_loaded) {
3308 // Tell libjsig jvm finishes setting signal handlers
3309 (*end_signal_setting)();
3310 }
3312 // We don't activate signal checker if libjsig is in place, we trust ourselves
3313 // and if UserSignalHandler is installed all bets are off
3314 if (CheckJNICalls) {
3315 if (libjsig_is_loaded) {
3316 if (PrintJNIResolving) {
3317 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3318 }
3319 check_signals = false;
3320 }
3321 if (AllowUserSignalHandlers) {
3322 if (PrintJNIResolving) {
3323 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3324 }
3325 check_signals = false;
3326 }
3327 }
3328 }
3329 }
3332 /////
3333 // glibc on Bsd platform uses non-documented flag
3334 // to indicate, that some special sort of signal
3335 // trampoline is used.
3336 // We will never set this flag, and we should
3337 // ignore this flag in our diagnostic
3338 #ifdef SIGNIFICANT_SIGNAL_MASK
3339 #undef SIGNIFICANT_SIGNAL_MASK
3340 #endif
3341 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3343 static const char* get_signal_handler_name(address handler,
3344 char* buf, int buflen) {
3345 int offset;
3346 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3347 if (found) {
3348 // skip directory names
3349 const char *p1, *p2;
3350 p1 = buf;
3351 size_t len = strlen(os::file_separator());
3352 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3353 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3354 } else {
3355 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3356 }
3357 return buf;
3358 }
3360 static void print_signal_handler(outputStream* st, int sig,
3361 char* buf, size_t buflen) {
3362 struct sigaction sa;
3364 sigaction(sig, NULL, &sa);
3366 // See comment for SIGNIFICANT_SIGNAL_MASK define
3367 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3369 st->print("%s: ", os::exception_name(sig, buf, buflen));
3371 address handler = (sa.sa_flags & SA_SIGINFO)
3372 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3373 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3375 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3376 st->print("SIG_DFL");
3377 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3378 st->print("SIG_IGN");
3379 } else {
3380 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3381 }
3383 st->print(", sa_mask[0]=");
3384 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3386 address rh = VMError::get_resetted_sighandler(sig);
3387 // May be, handler was resetted by VMError?
3388 if(rh != NULL) {
3389 handler = rh;
3390 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3391 }
3393 st->print(", sa_flags=");
3394 os::Posix::print_sa_flags(st, sa.sa_flags);
3396 // Check: is it our handler?
3397 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3398 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3399 // It is our signal handler
3400 // check for flags, reset system-used one!
3401 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3402 st->print(
3403 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3404 os::Bsd::get_our_sigflags(sig));
3405 }
3406 }
3407 st->cr();
3408 }
3411 #define DO_SIGNAL_CHECK(sig) \
3412 if (!sigismember(&check_signal_done, sig)) \
3413 os::Bsd::check_signal_handler(sig)
3415 // This method is a periodic task to check for misbehaving JNI applications
3416 // under CheckJNI, we can add any periodic checks here
3418 void os::run_periodic_checks() {
3420 if (check_signals == false) return;
3422 // SEGV and BUS if overridden could potentially prevent
3423 // generation of hs*.log in the event of a crash, debugging
3424 // such a case can be very challenging, so we absolutely
3425 // check the following for a good measure:
3426 DO_SIGNAL_CHECK(SIGSEGV);
3427 DO_SIGNAL_CHECK(SIGILL);
3428 DO_SIGNAL_CHECK(SIGFPE);
3429 DO_SIGNAL_CHECK(SIGBUS);
3430 DO_SIGNAL_CHECK(SIGPIPE);
3431 DO_SIGNAL_CHECK(SIGXFSZ);
3434 // ReduceSignalUsage allows the user to override these handlers
3435 // see comments at the very top and jvm_solaris.h
3436 if (!ReduceSignalUsage) {
3437 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3438 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3439 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3440 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3441 }
3443 DO_SIGNAL_CHECK(SR_signum);
3444 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3445 }
3447 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3449 static os_sigaction_t os_sigaction = NULL;
3451 void os::Bsd::check_signal_handler(int sig) {
3452 char buf[O_BUFLEN];
3453 address jvmHandler = NULL;
3456 struct sigaction act;
3457 if (os_sigaction == NULL) {
3458 // only trust the default sigaction, in case it has been interposed
3459 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3460 if (os_sigaction == NULL) return;
3461 }
3463 os_sigaction(sig, (struct sigaction*)NULL, &act);
3466 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3468 address thisHandler = (act.sa_flags & SA_SIGINFO)
3469 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3470 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3473 switch(sig) {
3474 case SIGSEGV:
3475 case SIGBUS:
3476 case SIGFPE:
3477 case SIGPIPE:
3478 case SIGILL:
3479 case SIGXFSZ:
3480 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3481 break;
3483 case SHUTDOWN1_SIGNAL:
3484 case SHUTDOWN2_SIGNAL:
3485 case SHUTDOWN3_SIGNAL:
3486 case BREAK_SIGNAL:
3487 jvmHandler = (address)user_handler();
3488 break;
3490 case INTERRUPT_SIGNAL:
3491 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3492 break;
3494 default:
3495 if (sig == SR_signum) {
3496 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3497 } else {
3498 return;
3499 }
3500 break;
3501 }
3503 if (thisHandler != jvmHandler) {
3504 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3505 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3506 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3507 // No need to check this sig any longer
3508 sigaddset(&check_signal_done, sig);
3509 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3510 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3511 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3512 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3513 // No need to check this sig any longer
3514 sigaddset(&check_signal_done, sig);
3515 }
3517 // Dump all the signal
3518 if (sigismember(&check_signal_done, sig)) {
3519 print_signal_handlers(tty, buf, O_BUFLEN);
3520 }
3521 }
3523 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3525 extern bool signal_name(int signo, char* buf, size_t len);
3527 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3528 if (0 < exception_code && exception_code <= SIGRTMAX) {
3529 // signal
3530 if (!signal_name(exception_code, buf, size)) {
3531 jio_snprintf(buf, size, "SIG%d", exception_code);
3532 }
3533 return buf;
3534 } else {
3535 return NULL;
3536 }
3537 }
3539 // this is called _before_ the most of global arguments have been parsed
3540 void os::init(void) {
3541 char dummy; /* used to get a guess on initial stack address */
3542 // first_hrtime = gethrtime();
3544 // With BsdThreads the JavaMain thread pid (primordial thread)
3545 // is different than the pid of the java launcher thread.
3546 // So, on Bsd, the launcher thread pid is passed to the VM
3547 // via the sun.java.launcher.pid property.
3548 // Use this property instead of getpid() if it was correctly passed.
3549 // See bug 6351349.
3550 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3552 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3554 clock_tics_per_sec = CLK_TCK;
3556 init_random(1234567);
3558 ThreadCritical::initialize();
3560 Bsd::set_page_size(getpagesize());
3561 if (Bsd::page_size() == -1) {
3562 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3563 strerror(errno)));
3564 }
3565 init_page_sizes((size_t) Bsd::page_size());
3567 Bsd::initialize_system_info();
3569 // main_thread points to the aboriginal thread
3570 Bsd::_main_thread = pthread_self();
3572 Bsd::clock_init();
3573 initial_time_count = javaTimeNanos();
3575 #ifdef __APPLE__
3576 // XXXDARWIN
3577 // Work around the unaligned VM callbacks in hotspot's
3578 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3579 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3580 // alignment when doing symbol lookup. To work around this, we force early
3581 // binding of all symbols now, thus binding when alignment is known-good.
3582 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3583 #endif
3584 }
3586 // To install functions for atexit system call
3587 extern "C" {
3588 static void perfMemory_exit_helper() {
3589 perfMemory_exit();
3590 }
3591 }
3593 // this is called _after_ the global arguments have been parsed
3594 jint os::init_2(void)
3595 {
3596 // Allocate a single page and mark it as readable for safepoint polling
3597 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3598 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3600 os::set_polling_page( polling_page );
3602 #ifndef PRODUCT
3603 if(Verbose && PrintMiscellaneous)
3604 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3605 #endif
3607 if (!UseMembar) {
3608 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3609 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3610 os::set_memory_serialize_page( mem_serialize_page );
3612 #ifndef PRODUCT
3613 if(Verbose && PrintMiscellaneous)
3614 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3615 #endif
3616 }
3618 // initialize suspend/resume support - must do this before signal_sets_init()
3619 if (SR_initialize() != 0) {
3620 perror("SR_initialize failed");
3621 return JNI_ERR;
3622 }
3624 Bsd::signal_sets_init();
3625 Bsd::install_signal_handlers();
3627 // Check minimum allowable stack size for thread creation and to initialize
3628 // the java system classes, including StackOverflowError - depends on page
3629 // size. Add a page for compiler2 recursion in main thread.
3630 // Add in 2*BytesPerWord times page size to account for VM stack during
3631 // class initialization depending on 32 or 64 bit VM.
3632 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3633 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3634 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3636 size_t threadStackSizeInBytes = ThreadStackSize * K;
3637 if (threadStackSizeInBytes != 0 &&
3638 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3639 tty->print_cr("\nThe stack size specified is too small, "
3640 "Specify at least %dk",
3641 os::Bsd::min_stack_allowed/ K);
3642 return JNI_ERR;
3643 }
3645 // Make the stack size a multiple of the page size so that
3646 // the yellow/red zones can be guarded.
3647 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3648 vm_page_size()));
3650 if (MaxFDLimit) {
3651 // set the number of file descriptors to max. print out error
3652 // if getrlimit/setrlimit fails but continue regardless.
3653 struct rlimit nbr_files;
3654 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3655 if (status != 0) {
3656 if (PrintMiscellaneous && (Verbose || WizardMode))
3657 perror("os::init_2 getrlimit failed");
3658 } else {
3659 nbr_files.rlim_cur = nbr_files.rlim_max;
3661 #ifdef __APPLE__
3662 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3663 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3664 // be used instead
3665 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3666 #endif
3668 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3669 if (status != 0) {
3670 if (PrintMiscellaneous && (Verbose || WizardMode))
3671 perror("os::init_2 setrlimit failed");
3672 }
3673 }
3674 }
3676 // at-exit methods are called in the reverse order of their registration.
3677 // atexit functions are called on return from main or as a result of a
3678 // call to exit(3C). There can be only 32 of these functions registered
3679 // and atexit() does not set errno.
3681 if (PerfAllowAtExitRegistration) {
3682 // only register atexit functions if PerfAllowAtExitRegistration is set.
3683 // atexit functions can be delayed until process exit time, which
3684 // can be problematic for embedded VM situations. Embedded VMs should
3685 // call DestroyJavaVM() to assure that VM resources are released.
3687 // note: perfMemory_exit_helper atexit function may be removed in
3688 // the future if the appropriate cleanup code can be added to the
3689 // VM_Exit VMOperation's doit method.
3690 if (atexit(perfMemory_exit_helper) != 0) {
3691 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3692 }
3693 }
3695 // initialize thread priority policy
3696 prio_init();
3698 #ifdef __APPLE__
3699 // dynamically link to objective c gc registration
3700 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3701 if (handleLibObjc != NULL) {
3702 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3703 }
3704 #endif
3706 return JNI_OK;
3707 }
3709 // this is called at the end of vm_initialization
3710 void os::init_3(void) { }
3712 // Mark the polling page as unreadable
3713 void os::make_polling_page_unreadable(void) {
3714 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3715 fatal("Could not disable polling page");
3716 };
3718 // Mark the polling page as readable
3719 void os::make_polling_page_readable(void) {
3720 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3721 fatal("Could not enable polling page");
3722 }
3723 };
3725 int os::active_processor_count() {
3726 return _processor_count;
3727 }
3729 void os::set_native_thread_name(const char *name) {
3730 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3731 // This is only supported in Snow Leopard and beyond
3732 if (name != NULL) {
3733 // Add a "Java: " prefix to the name
3734 char buf[MAXTHREADNAMESIZE];
3735 snprintf(buf, sizeof(buf), "Java: %s", name);
3736 pthread_setname_np(buf);
3737 }
3738 #endif
3739 }
3741 bool os::distribute_processes(uint length, uint* distribution) {
3742 // Not yet implemented.
3743 return false;
3744 }
3746 bool os::bind_to_processor(uint processor_id) {
3747 // Not yet implemented.
3748 return false;
3749 }
3751 void os::SuspendedThreadTask::internal_do_task() {
3752 if (do_suspend(_thread->osthread())) {
3753 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3754 do_task(context);
3755 do_resume(_thread->osthread());
3756 }
3757 }
3759 ///
3760 class PcFetcher : public os::SuspendedThreadTask {
3761 public:
3762 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3763 ExtendedPC result();
3764 protected:
3765 void do_task(const os::SuspendedThreadTaskContext& context);
3766 private:
3767 ExtendedPC _epc;
3768 };
3770 ExtendedPC PcFetcher::result() {
3771 guarantee(is_done(), "task is not done yet.");
3772 return _epc;
3773 }
3775 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3776 Thread* thread = context.thread();
3777 OSThread* osthread = thread->osthread();
3778 if (osthread->ucontext() != NULL) {
3779 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3780 } else {
3781 // NULL context is unexpected, double-check this is the VMThread
3782 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3783 }
3784 }
3786 // Suspends the target using the signal mechanism and then grabs the PC before
3787 // resuming the target. Used by the flat-profiler only
3788 ExtendedPC os::get_thread_pc(Thread* thread) {
3789 // Make sure that it is called by the watcher for the VMThread
3790 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3791 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3793 PcFetcher fetcher(thread);
3794 fetcher.run();
3795 return fetcher.result();
3796 }
3798 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3799 {
3800 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3801 }
3803 ////////////////////////////////////////////////////////////////////////////////
3804 // debug support
3806 bool os::find(address addr, outputStream* st) {
3807 Dl_info dlinfo;
3808 memset(&dlinfo, 0, sizeof(dlinfo));
3809 if (dladdr(addr, &dlinfo) != 0) {
3810 st->print(PTR_FORMAT ": ", addr);
3811 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3812 st->print("%s+%#x", dlinfo.dli_sname,
3813 addr - (intptr_t)dlinfo.dli_saddr);
3814 } else if (dlinfo.dli_fbase != NULL) {
3815 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3816 } else {
3817 st->print("<absolute address>");
3818 }
3819 if (dlinfo.dli_fname != NULL) {
3820 st->print(" in %s", dlinfo.dli_fname);
3821 }
3822 if (dlinfo.dli_fbase != NULL) {
3823 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3824 }
3825 st->cr();
3827 if (Verbose) {
3828 // decode some bytes around the PC
3829 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3830 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3831 address lowest = (address) dlinfo.dli_sname;
3832 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3833 if (begin < lowest) begin = lowest;
3834 Dl_info dlinfo2;
3835 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3836 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3837 end = (address) dlinfo2.dli_saddr;
3838 Disassembler::decode(begin, end, st);
3839 }
3840 return true;
3841 }
3842 return false;
3843 }
3845 ////////////////////////////////////////////////////////////////////////////////
3846 // misc
3848 // This does not do anything on Bsd. This is basically a hook for being
3849 // able to use structured exception handling (thread-local exception filters)
3850 // on, e.g., Win32.
3851 void
3852 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3853 JavaCallArguments* args, Thread* thread) {
3854 f(value, method, args, thread);
3855 }
3857 void os::print_statistics() {
3858 }
3860 int os::message_box(const char* title, const char* message) {
3861 int i;
3862 fdStream err(defaultStream::error_fd());
3863 for (i = 0; i < 78; i++) err.print_raw("=");
3864 err.cr();
3865 err.print_raw_cr(title);
3866 for (i = 0; i < 78; i++) err.print_raw("-");
3867 err.cr();
3868 err.print_raw_cr(message);
3869 for (i = 0; i < 78; i++) err.print_raw("=");
3870 err.cr();
3872 char buf[16];
3873 // Prevent process from exiting upon "read error" without consuming all CPU
3874 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3876 return buf[0] == 'y' || buf[0] == 'Y';
3877 }
3879 int os::stat(const char *path, struct stat *sbuf) {
3880 char pathbuf[MAX_PATH];
3881 if (strlen(path) > MAX_PATH - 1) {
3882 errno = ENAMETOOLONG;
3883 return -1;
3884 }
3885 os::native_path(strcpy(pathbuf, path));
3886 return ::stat(pathbuf, sbuf);
3887 }
3889 bool os::check_heap(bool force) {
3890 return true;
3891 }
3893 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3894 return ::vsnprintf(buf, count, format, args);
3895 }
3897 // Is a (classpath) directory empty?
3898 bool os::dir_is_empty(const char* path) {
3899 DIR *dir = NULL;
3900 struct dirent *ptr;
3902 dir = opendir(path);
3903 if (dir == NULL) return true;
3905 /* Scan the directory */
3906 bool result = true;
3907 char buf[sizeof(struct dirent) + MAX_PATH];
3908 while (result && (ptr = ::readdir(dir)) != NULL) {
3909 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3910 result = false;
3911 }
3912 }
3913 closedir(dir);
3914 return result;
3915 }
3917 // This code originates from JDK's sysOpen and open64_w
3918 // from src/solaris/hpi/src/system_md.c
3920 #ifndef O_DELETE
3921 #define O_DELETE 0x10000
3922 #endif
3924 // Open a file. Unlink the file immediately after open returns
3925 // if the specified oflag has the O_DELETE flag set.
3926 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3928 int os::open(const char *path, int oflag, int mode) {
3930 if (strlen(path) > MAX_PATH - 1) {
3931 errno = ENAMETOOLONG;
3932 return -1;
3933 }
3934 int fd;
3935 int o_delete = (oflag & O_DELETE);
3936 oflag = oflag & ~O_DELETE;
3938 fd = ::open(path, oflag, mode);
3939 if (fd == -1) return -1;
3941 //If the open succeeded, the file might still be a directory
3942 {
3943 struct stat buf;
3944 int ret = ::fstat(fd, &buf);
3945 int st_mode = buf.st_mode;
3947 if (ret != -1) {
3948 if ((st_mode & S_IFMT) == S_IFDIR) {
3949 errno = EISDIR;
3950 ::close(fd);
3951 return -1;
3952 }
3953 } else {
3954 ::close(fd);
3955 return -1;
3956 }
3957 }
3959 /*
3960 * All file descriptors that are opened in the JVM and not
3961 * specifically destined for a subprocess should have the
3962 * close-on-exec flag set. If we don't set it, then careless 3rd
3963 * party native code might fork and exec without closing all
3964 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3965 * UNIXProcess.c), and this in turn might:
3966 *
3967 * - cause end-of-file to fail to be detected on some file
3968 * descriptors, resulting in mysterious hangs, or
3969 *
3970 * - might cause an fopen in the subprocess to fail on a system
3971 * suffering from bug 1085341.
3972 *
3973 * (Yes, the default setting of the close-on-exec flag is a Unix
3974 * design flaw)
3975 *
3976 * See:
3977 * 1085341: 32-bit stdio routines should support file descriptors >255
3978 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3979 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3980 */
3981 #ifdef FD_CLOEXEC
3982 {
3983 int flags = ::fcntl(fd, F_GETFD);
3984 if (flags != -1)
3985 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3986 }
3987 #endif
3989 if (o_delete != 0) {
3990 ::unlink(path);
3991 }
3992 return fd;
3993 }
3996 // create binary file, rewriting existing file if required
3997 int os::create_binary_file(const char* path, bool rewrite_existing) {
3998 int oflags = O_WRONLY | O_CREAT;
3999 if (!rewrite_existing) {
4000 oflags |= O_EXCL;
4001 }
4002 return ::open(path, oflags, S_IREAD | S_IWRITE);
4003 }
4005 // return current position of file pointer
4006 jlong os::current_file_offset(int fd) {
4007 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4008 }
4010 // move file pointer to the specified offset
4011 jlong os::seek_to_file_offset(int fd, jlong offset) {
4012 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4013 }
4015 // This code originates from JDK's sysAvailable
4016 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4018 int os::available(int fd, jlong *bytes) {
4019 jlong cur, end;
4020 int mode;
4021 struct stat buf;
4023 if (::fstat(fd, &buf) >= 0) {
4024 mode = buf.st_mode;
4025 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4026 /*
4027 * XXX: is the following call interruptible? If so, this might
4028 * need to go through the INTERRUPT_IO() wrapper as for other
4029 * blocking, interruptible calls in this file.
4030 */
4031 int n;
4032 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4033 *bytes = n;
4034 return 1;
4035 }
4036 }
4037 }
4038 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4039 return 0;
4040 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4041 return 0;
4042 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4043 return 0;
4044 }
4045 *bytes = end - cur;
4046 return 1;
4047 }
4049 int os::socket_available(int fd, jint *pbytes) {
4050 if (fd < 0)
4051 return OS_OK;
4053 int ret;
4055 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4057 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4058 // is expected to return 0 on failure and 1 on success to the jdk.
4060 return (ret == OS_ERR) ? 0 : 1;
4061 }
4063 // Map a block of memory.
4064 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4065 char *addr, size_t bytes, bool read_only,
4066 bool allow_exec) {
4067 int prot;
4068 int flags;
4070 if (read_only) {
4071 prot = PROT_READ;
4072 flags = MAP_SHARED;
4073 } else {
4074 prot = PROT_READ | PROT_WRITE;
4075 flags = MAP_PRIVATE;
4076 }
4078 if (allow_exec) {
4079 prot |= PROT_EXEC;
4080 }
4082 if (addr != NULL) {
4083 flags |= MAP_FIXED;
4084 }
4086 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4087 fd, file_offset);
4088 if (mapped_address == MAP_FAILED) {
4089 return NULL;
4090 }
4091 return mapped_address;
4092 }
4095 // Remap a block of memory.
4096 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4097 char *addr, size_t bytes, bool read_only,
4098 bool allow_exec) {
4099 // same as map_memory() on this OS
4100 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4101 allow_exec);
4102 }
4105 // Unmap a block of memory.
4106 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4107 return munmap(addr, bytes) == 0;
4108 }
4110 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4111 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4112 // of a thread.
4113 //
4114 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4115 // the fast estimate available on the platform.
4117 jlong os::current_thread_cpu_time() {
4118 #ifdef __APPLE__
4119 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4120 #else
4121 Unimplemented();
4122 return 0;
4123 #endif
4124 }
4126 jlong os::thread_cpu_time(Thread* thread) {
4127 #ifdef __APPLE__
4128 return os::thread_cpu_time(thread, true /* user + sys */);
4129 #else
4130 Unimplemented();
4131 return 0;
4132 #endif
4133 }
4135 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4136 #ifdef __APPLE__
4137 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4138 #else
4139 Unimplemented();
4140 return 0;
4141 #endif
4142 }
4144 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4145 #ifdef __APPLE__
4146 struct thread_basic_info tinfo;
4147 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4148 kern_return_t kr;
4149 thread_t mach_thread;
4151 mach_thread = thread->osthread()->thread_id();
4152 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4153 if (kr != KERN_SUCCESS)
4154 return -1;
4156 if (user_sys_cpu_time) {
4157 jlong nanos;
4158 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4159 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4160 return nanos;
4161 } else {
4162 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4163 }
4164 #else
4165 Unimplemented();
4166 return 0;
4167 #endif
4168 }
4171 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4172 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4173 info_ptr->may_skip_backward = false; // elapsed time not wall time
4174 info_ptr->may_skip_forward = false; // elapsed time not wall time
4175 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4176 }
4178 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4179 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4180 info_ptr->may_skip_backward = false; // elapsed time not wall time
4181 info_ptr->may_skip_forward = false; // elapsed time not wall time
4182 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4183 }
4185 bool os::is_thread_cpu_time_supported() {
4186 #ifdef __APPLE__
4187 return true;
4188 #else
4189 return false;
4190 #endif
4191 }
4193 // System loadavg support. Returns -1 if load average cannot be obtained.
4194 // Bsd doesn't yet have a (official) notion of processor sets,
4195 // so just return the system wide load average.
4196 int os::loadavg(double loadavg[], int nelem) {
4197 return ::getloadavg(loadavg, nelem);
4198 }
4200 void os::pause() {
4201 char filename[MAX_PATH];
4202 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4203 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4204 } else {
4205 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4206 }
4208 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4209 if (fd != -1) {
4210 struct stat buf;
4211 ::close(fd);
4212 while (::stat(filename, &buf) == 0) {
4213 (void)::poll(NULL, 0, 100);
4214 }
4215 } else {
4216 jio_fprintf(stderr,
4217 "Could not open pause file '%s', continuing immediately.\n", filename);
4218 }
4219 }
4222 // Refer to the comments in os_solaris.cpp park-unpark.
4223 //
4224 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4225 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4226 // For specifics regarding the bug see GLIBC BUGID 261237 :
4227 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4228 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4229 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4230 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4231 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4232 // and monitorenter when we're using 1-0 locking. All those operations may result in
4233 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4234 // of libpthread avoids the problem, but isn't practical.
4235 //
4236 // Possible remedies:
4237 //
4238 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4239 // This is palliative and probabilistic, however. If the thread is preempted
4240 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4241 // than the minimum period may have passed, and the abstime may be stale (in the
4242 // past) resultin in a hang. Using this technique reduces the odds of a hang
4243 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4244 //
4245 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4246 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4247 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4248 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4249 // thread.
4250 //
4251 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4252 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4253 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4254 // This also works well. In fact it avoids kernel-level scalability impediments
4255 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4256 // timers in a graceful fashion.
4257 //
4258 // 4. When the abstime value is in the past it appears that control returns
4259 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4260 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4261 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4262 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4263 // It may be possible to avoid reinitialization by checking the return
4264 // value from pthread_cond_timedwait(). In addition to reinitializing the
4265 // condvar we must establish the invariant that cond_signal() is only called
4266 // within critical sections protected by the adjunct mutex. This prevents
4267 // cond_signal() from "seeing" a condvar that's in the midst of being
4268 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4269 // desirable signal-after-unlock optimization that avoids futile context switching.
4270 //
4271 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4272 // structure when a condvar is used or initialized. cond_destroy() would
4273 // release the helper structure. Our reinitialize-after-timedwait fix
4274 // put excessive stress on malloc/free and locks protecting the c-heap.
4275 //
4276 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4277 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4278 // and only enabling the work-around for vulnerable environments.
4280 // utility to compute the abstime argument to timedwait:
4281 // millis is the relative timeout time
4282 // abstime will be the absolute timeout time
4283 // TODO: replace compute_abstime() with unpackTime()
4285 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4286 if (millis < 0) millis = 0;
4287 struct timeval now;
4288 int status = gettimeofday(&now, NULL);
4289 assert(status == 0, "gettimeofday");
4290 jlong seconds = millis / 1000;
4291 millis %= 1000;
4292 if (seconds > 50000000) { // see man cond_timedwait(3T)
4293 seconds = 50000000;
4294 }
4295 abstime->tv_sec = now.tv_sec + seconds;
4296 long usec = now.tv_usec + millis * 1000;
4297 if (usec >= 1000000) {
4298 abstime->tv_sec += 1;
4299 usec -= 1000000;
4300 }
4301 abstime->tv_nsec = usec * 1000;
4302 return abstime;
4303 }
4306 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4307 // Conceptually TryPark() should be equivalent to park(0).
4309 int os::PlatformEvent::TryPark() {
4310 for (;;) {
4311 const int v = _Event ;
4312 guarantee ((v == 0) || (v == 1), "invariant") ;
4313 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4314 }
4315 }
4317 void os::PlatformEvent::park() { // AKA "down()"
4318 // Invariant: Only the thread associated with the Event/PlatformEvent
4319 // may call park().
4320 // TODO: assert that _Assoc != NULL or _Assoc == Self
4321 int v ;
4322 for (;;) {
4323 v = _Event ;
4324 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4325 }
4326 guarantee (v >= 0, "invariant") ;
4327 if (v == 0) {
4328 // Do this the hard way by blocking ...
4329 int status = pthread_mutex_lock(_mutex);
4330 assert_status(status == 0, status, "mutex_lock");
4331 guarantee (_nParked == 0, "invariant") ;
4332 ++ _nParked ;
4333 while (_Event < 0) {
4334 status = pthread_cond_wait(_cond, _mutex);
4335 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4336 // Treat this the same as if the wait was interrupted
4337 if (status == ETIMEDOUT) { status = EINTR; }
4338 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4339 }
4340 -- _nParked ;
4342 _Event = 0 ;
4343 status = pthread_mutex_unlock(_mutex);
4344 assert_status(status == 0, status, "mutex_unlock");
4345 // Paranoia to ensure our locked and lock-free paths interact
4346 // correctly with each other.
4347 OrderAccess::fence();
4348 }
4349 guarantee (_Event >= 0, "invariant") ;
4350 }
4352 int os::PlatformEvent::park(jlong millis) {
4353 guarantee (_nParked == 0, "invariant") ;
4355 int v ;
4356 for (;;) {
4357 v = _Event ;
4358 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4359 }
4360 guarantee (v >= 0, "invariant") ;
4361 if (v != 0) return OS_OK ;
4363 // We do this the hard way, by blocking the thread.
4364 // Consider enforcing a minimum timeout value.
4365 struct timespec abst;
4366 compute_abstime(&abst, millis);
4368 int ret = OS_TIMEOUT;
4369 int status = pthread_mutex_lock(_mutex);
4370 assert_status(status == 0, status, "mutex_lock");
4371 guarantee (_nParked == 0, "invariant") ;
4372 ++_nParked ;
4374 // Object.wait(timo) will return because of
4375 // (a) notification
4376 // (b) timeout
4377 // (c) thread.interrupt
4378 //
4379 // Thread.interrupt and object.notify{All} both call Event::set.
4380 // That is, we treat thread.interrupt as a special case of notification.
4381 // The underlying Solaris implementation, cond_timedwait, admits
4382 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4383 // JVM from making those visible to Java code. As such, we must
4384 // filter out spurious wakeups. We assume all ETIME returns are valid.
4385 //
4386 // TODO: properly differentiate simultaneous notify+interrupt.
4387 // In that case, we should propagate the notify to another waiter.
4389 while (_Event < 0) {
4390 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4391 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4392 pthread_cond_destroy (_cond);
4393 pthread_cond_init (_cond, NULL) ;
4394 }
4395 assert_status(status == 0 || status == EINTR ||
4396 status == ETIMEDOUT,
4397 status, "cond_timedwait");
4398 if (!FilterSpuriousWakeups) break ; // previous semantics
4399 if (status == ETIMEDOUT) break ;
4400 // We consume and ignore EINTR and spurious wakeups.
4401 }
4402 --_nParked ;
4403 if (_Event >= 0) {
4404 ret = OS_OK;
4405 }
4406 _Event = 0 ;
4407 status = pthread_mutex_unlock(_mutex);
4408 assert_status(status == 0, status, "mutex_unlock");
4409 assert (_nParked == 0, "invariant") ;
4410 // Paranoia to ensure our locked and lock-free paths interact
4411 // correctly with each other.
4412 OrderAccess::fence();
4413 return ret;
4414 }
4416 void os::PlatformEvent::unpark() {
4417 // Transitions for _Event:
4418 // 0 :=> 1
4419 // 1 :=> 1
4420 // -1 :=> either 0 or 1; must signal target thread
4421 // That is, we can safely transition _Event from -1 to either
4422 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4423 // unpark() calls.
4424 // See also: "Semaphores in Plan 9" by Mullender & Cox
4425 //
4426 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4427 // that it will take two back-to-back park() calls for the owning
4428 // thread to block. This has the benefit of forcing a spurious return
4429 // from the first park() call after an unpark() call which will help
4430 // shake out uses of park() and unpark() without condition variables.
4432 if (Atomic::xchg(1, &_Event) >= 0) return;
4434 // Wait for the thread associated with the event to vacate
4435 int status = pthread_mutex_lock(_mutex);
4436 assert_status(status == 0, status, "mutex_lock");
4437 int AnyWaiters = _nParked;
4438 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4439 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4440 AnyWaiters = 0;
4441 pthread_cond_signal(_cond);
4442 }
4443 status = pthread_mutex_unlock(_mutex);
4444 assert_status(status == 0, status, "mutex_unlock");
4445 if (AnyWaiters != 0) {
4446 status = pthread_cond_signal(_cond);
4447 assert_status(status == 0, status, "cond_signal");
4448 }
4450 // Note that we signal() _after dropping the lock for "immortal" Events.
4451 // This is safe and avoids a common class of futile wakeups. In rare
4452 // circumstances this can cause a thread to return prematurely from
4453 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4454 // simply re-test the condition and re-park itself.
4455 }
4458 // JSR166
4459 // -------------------------------------------------------
4461 /*
4462 * The solaris and bsd implementations of park/unpark are fairly
4463 * conservative for now, but can be improved. They currently use a
4464 * mutex/condvar pair, plus a a count.
4465 * Park decrements count if > 0, else does a condvar wait. Unpark
4466 * sets count to 1 and signals condvar. Only one thread ever waits
4467 * on the condvar. Contention seen when trying to park implies that someone
4468 * is unparking you, so don't wait. And spurious returns are fine, so there
4469 * is no need to track notifications.
4470 */
4472 #define MAX_SECS 100000000
4473 /*
4474 * This code is common to bsd and solaris and will be moved to a
4475 * common place in dolphin.
4476 *
4477 * The passed in time value is either a relative time in nanoseconds
4478 * or an absolute time in milliseconds. Either way it has to be unpacked
4479 * into suitable seconds and nanoseconds components and stored in the
4480 * given timespec structure.
4481 * Given time is a 64-bit value and the time_t used in the timespec is only
4482 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4483 * overflow if times way in the future are given. Further on Solaris versions
4484 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4485 * number of seconds, in abstime, is less than current_time + 100,000,000.
4486 * As it will be 28 years before "now + 100000000" will overflow we can
4487 * ignore overflow and just impose a hard-limit on seconds using the value
4488 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4489 * years from "now".
4490 */
4492 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4493 assert (time > 0, "convertTime");
4495 struct timeval now;
4496 int status = gettimeofday(&now, NULL);
4497 assert(status == 0, "gettimeofday");
4499 time_t max_secs = now.tv_sec + MAX_SECS;
4501 if (isAbsolute) {
4502 jlong secs = time / 1000;
4503 if (secs > max_secs) {
4504 absTime->tv_sec = max_secs;
4505 }
4506 else {
4507 absTime->tv_sec = secs;
4508 }
4509 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4510 }
4511 else {
4512 jlong secs = time / NANOSECS_PER_SEC;
4513 if (secs >= MAX_SECS) {
4514 absTime->tv_sec = max_secs;
4515 absTime->tv_nsec = 0;
4516 }
4517 else {
4518 absTime->tv_sec = now.tv_sec + secs;
4519 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4520 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4521 absTime->tv_nsec -= NANOSECS_PER_SEC;
4522 ++absTime->tv_sec; // note: this must be <= max_secs
4523 }
4524 }
4525 }
4526 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4527 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4528 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4529 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4530 }
4532 void Parker::park(bool isAbsolute, jlong time) {
4533 // Ideally we'd do something useful while spinning, such
4534 // as calling unpackTime().
4536 // Optional fast-path check:
4537 // Return immediately if a permit is available.
4538 // We depend on Atomic::xchg() having full barrier semantics
4539 // since we are doing a lock-free update to _counter.
4540 if (Atomic::xchg(0, &_counter) > 0) return;
4542 Thread* thread = Thread::current();
4543 assert(thread->is_Java_thread(), "Must be JavaThread");
4544 JavaThread *jt = (JavaThread *)thread;
4546 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4547 // Check interrupt before trying to wait
4548 if (Thread::is_interrupted(thread, false)) {
4549 return;
4550 }
4552 // Next, demultiplex/decode time arguments
4553 struct timespec absTime;
4554 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4555 return;
4556 }
4557 if (time > 0) {
4558 unpackTime(&absTime, isAbsolute, time);
4559 }
4562 // Enter safepoint region
4563 // Beware of deadlocks such as 6317397.
4564 // The per-thread Parker:: mutex is a classic leaf-lock.
4565 // In particular a thread must never block on the Threads_lock while
4566 // holding the Parker:: mutex. If safepoints are pending both the
4567 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4568 ThreadBlockInVM tbivm(jt);
4570 // Don't wait if cannot get lock since interference arises from
4571 // unblocking. Also. check interrupt before trying wait
4572 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4573 return;
4574 }
4576 int status ;
4577 if (_counter > 0) { // no wait needed
4578 _counter = 0;
4579 status = pthread_mutex_unlock(_mutex);
4580 assert (status == 0, "invariant") ;
4581 // Paranoia to ensure our locked and lock-free paths interact
4582 // correctly with each other and Java-level accesses.
4583 OrderAccess::fence();
4584 return;
4585 }
4587 #ifdef ASSERT
4588 // Don't catch signals while blocked; let the running threads have the signals.
4589 // (This allows a debugger to break into the running thread.)
4590 sigset_t oldsigs;
4591 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4592 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4593 #endif
4595 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4596 jt->set_suspend_equivalent();
4597 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4599 if (time == 0) {
4600 status = pthread_cond_wait (_cond, _mutex) ;
4601 } else {
4602 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4603 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4604 pthread_cond_destroy (_cond) ;
4605 pthread_cond_init (_cond, NULL);
4606 }
4607 }
4608 assert_status(status == 0 || status == EINTR ||
4609 status == ETIMEDOUT,
4610 status, "cond_timedwait");
4612 #ifdef ASSERT
4613 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4614 #endif
4616 _counter = 0 ;
4617 status = pthread_mutex_unlock(_mutex) ;
4618 assert_status(status == 0, status, "invariant") ;
4619 // Paranoia to ensure our locked and lock-free paths interact
4620 // correctly with each other and Java-level accesses.
4621 OrderAccess::fence();
4623 // If externally suspended while waiting, re-suspend
4624 if (jt->handle_special_suspend_equivalent_condition()) {
4625 jt->java_suspend_self();
4626 }
4627 }
4629 void Parker::unpark() {
4630 int s, status ;
4631 status = pthread_mutex_lock(_mutex);
4632 assert (status == 0, "invariant") ;
4633 s = _counter;
4634 _counter = 1;
4635 if (s < 1) {
4636 if (WorkAroundNPTLTimedWaitHang) {
4637 status = pthread_cond_signal (_cond) ;
4638 assert (status == 0, "invariant") ;
4639 status = pthread_mutex_unlock(_mutex);
4640 assert (status == 0, "invariant") ;
4641 } else {
4642 status = pthread_mutex_unlock(_mutex);
4643 assert (status == 0, "invariant") ;
4644 status = pthread_cond_signal (_cond) ;
4645 assert (status == 0, "invariant") ;
4646 }
4647 } else {
4648 pthread_mutex_unlock(_mutex);
4649 assert (status == 0, "invariant") ;
4650 }
4651 }
4654 /* Darwin has no "environ" in a dynamic library. */
4655 #ifdef __APPLE__
4656 #include <crt_externs.h>
4657 #define environ (*_NSGetEnviron())
4658 #else
4659 extern char** environ;
4660 #endif
4662 // Run the specified command in a separate process. Return its exit value,
4663 // or -1 on failure (e.g. can't fork a new process).
4664 // Unlike system(), this function can be called from signal handler. It
4665 // doesn't block SIGINT et al.
4666 int os::fork_and_exec(char* cmd) {
4667 const char * argv[4] = {"sh", "-c", cmd, NULL};
4669 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4670 // pthread_atfork handlers and reset pthread library. All we need is a
4671 // separate process to execve. Make a direct syscall to fork process.
4672 // On IA64 there's no fork syscall, we have to use fork() and hope for
4673 // the best...
4674 pid_t pid = fork();
4676 if (pid < 0) {
4677 // fork failed
4678 return -1;
4680 } else if (pid == 0) {
4681 // child process
4683 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4684 // first to kill every thread on the thread list. Because this list is
4685 // not reset by fork() (see notes above), execve() will instead kill
4686 // every thread in the parent process. We know this is the only thread
4687 // in the new process, so make a system call directly.
4688 // IA64 should use normal execve() from glibc to match the glibc fork()
4689 // above.
4690 execve("/bin/sh", (char* const*)argv, environ);
4692 // execve failed
4693 _exit(-1);
4695 } else {
4696 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4697 // care about the actual exit code, for now.
4699 int status;
4701 // Wait for the child process to exit. This returns immediately if
4702 // the child has already exited. */
4703 while (waitpid(pid, &status, 0) < 0) {
4704 switch (errno) {
4705 case ECHILD: return 0;
4706 case EINTR: break;
4707 default: return -1;
4708 }
4709 }
4711 if (WIFEXITED(status)) {
4712 // The child exited normally; get its exit code.
4713 return WEXITSTATUS(status);
4714 } else if (WIFSIGNALED(status)) {
4715 // The child exited because of a signal
4716 // The best value to return is 0x80 + signal number,
4717 // because that is what all Unix shells do, and because
4718 // it allows callers to distinguish between process exit and
4719 // process death by signal.
4720 return 0x80 + WTERMSIG(status);
4721 } else {
4722 // Unknown exit code; pass it through
4723 return status;
4724 }
4725 }
4726 }
4728 // is_headless_jre()
4729 //
4730 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4731 // in order to report if we are running in a headless jre
4732 //
4733 // Since JDK8 xawt/libmawt.so was moved into the same directory
4734 // as libawt.so, and renamed libawt_xawt.so
4735 //
4736 bool os::is_headless_jre() {
4737 #ifdef __APPLE__
4738 // We no longer build headless-only on Mac OS X
4739 return false;
4740 #else
4741 struct stat statbuf;
4742 char buf[MAXPATHLEN];
4743 char libmawtpath[MAXPATHLEN];
4744 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4745 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4746 char *p;
4748 // Get path to libjvm.so
4749 os::jvm_path(buf, sizeof(buf));
4751 // Get rid of libjvm.so
4752 p = strrchr(buf, '/');
4753 if (p == NULL) return false;
4754 else *p = '\0';
4756 // Get rid of client or server
4757 p = strrchr(buf, '/');
4758 if (p == NULL) return false;
4759 else *p = '\0';
4761 // check xawt/libmawt.so
4762 strcpy(libmawtpath, buf);
4763 strcat(libmawtpath, xawtstr);
4764 if (::stat(libmawtpath, &statbuf) == 0) return false;
4766 // check libawt_xawt.so
4767 strcpy(libmawtpath, buf);
4768 strcat(libmawtpath, new_xawtstr);
4769 if (::stat(libmawtpath, &statbuf) == 0) return false;
4771 return true;
4772 #endif
4773 }
4775 // Get the default path to the core file
4776 // Returns the length of the string
4777 int os::get_core_path(char* buffer, size_t bufferSize) {
4778 int n = jio_snprintf(buffer, bufferSize, "/cores");
4780 // Truncate if theoretical string was longer than bufferSize
4781 n = MIN2(n, (int)bufferSize);
4783 return n;
4784 }
4786 #ifndef PRODUCT
4787 void TestReserveMemorySpecial_test() {
4788 // No tests available for this platform
4789 }
4790 #endif