Thu, 13 Mar 2014 14:57:01 -0700
Merge
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 // no precompiled headers
26 #include "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
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 int os::allocate_thread_local_storage() {
918 pthread_key_t key;
919 int rslt = pthread_key_create(&key, NULL);
920 assert(rslt == 0, "cannot allocate thread local storage");
921 return (int)key;
922 }
924 // Note: This is currently not used by VM, as we don't destroy TLS key
925 // on VM exit.
926 void os::free_thread_local_storage(int index) {
927 int rslt = pthread_key_delete((pthread_key_t)index);
928 assert(rslt == 0, "invalid index");
929 }
931 void os::thread_local_storage_at_put(int index, void* value) {
932 int rslt = pthread_setspecific((pthread_key_t)index, value);
933 assert(rslt == 0, "pthread_setspecific failed");
934 }
936 extern "C" Thread* get_thread() {
937 return ThreadLocalStorage::thread();
938 }
941 ////////////////////////////////////////////////////////////////////////////////
942 // time support
944 // Time since start-up in seconds to a fine granularity.
945 // Used by VMSelfDestructTimer and the MemProfiler.
946 double os::elapsedTime() {
948 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
949 }
951 jlong os::elapsed_counter() {
952 return javaTimeNanos() - initial_time_count;
953 }
955 jlong os::elapsed_frequency() {
956 return NANOSECS_PER_SEC; // nanosecond resolution
957 }
959 bool os::supports_vtime() { return true; }
960 bool os::enable_vtime() { return false; }
961 bool os::vtime_enabled() { return false; }
963 double os::elapsedVTime() {
964 // better than nothing, but not much
965 return elapsedTime();
966 }
968 jlong os::javaTimeMillis() {
969 timeval time;
970 int status = gettimeofday(&time, NULL);
971 assert(status != -1, "bsd error");
972 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
973 }
975 #ifndef CLOCK_MONOTONIC
976 #define CLOCK_MONOTONIC (1)
977 #endif
979 #ifdef __APPLE__
980 void os::Bsd::clock_init() {
981 // XXXDARWIN: Investigate replacement monotonic clock
982 }
983 #else
984 void os::Bsd::clock_init() {
985 struct timespec res;
986 struct timespec tp;
987 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
988 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
989 // yes, monotonic clock is supported
990 _clock_gettime = ::clock_gettime;
991 }
992 }
993 #endif
996 jlong os::javaTimeNanos() {
997 if (Bsd::supports_monotonic_clock()) {
998 struct timespec tp;
999 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1000 assert(status == 0, "gettime error");
1001 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1002 return result;
1003 } else {
1004 timeval time;
1005 int status = gettimeofday(&time, NULL);
1006 assert(status != -1, "bsd error");
1007 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1008 return 1000 * usecs;
1009 }
1010 }
1012 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1013 if (Bsd::supports_monotonic_clock()) {
1014 info_ptr->max_value = ALL_64_BITS;
1016 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1017 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1018 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1019 } else {
1020 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1021 info_ptr->max_value = ALL_64_BITS;
1023 // gettimeofday is a real time clock so it skips
1024 info_ptr->may_skip_backward = true;
1025 info_ptr->may_skip_forward = true;
1026 }
1028 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1029 }
1031 // Return the real, user, and system times in seconds from an
1032 // arbitrary fixed point in the past.
1033 bool os::getTimesSecs(double* process_real_time,
1034 double* process_user_time,
1035 double* process_system_time) {
1036 struct tms ticks;
1037 clock_t real_ticks = times(&ticks);
1039 if (real_ticks == (clock_t) (-1)) {
1040 return false;
1041 } else {
1042 double ticks_per_second = (double) clock_tics_per_sec;
1043 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1044 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1045 *process_real_time = ((double) real_ticks) / ticks_per_second;
1047 return true;
1048 }
1049 }
1052 char * os::local_time_string(char *buf, size_t buflen) {
1053 struct tm t;
1054 time_t long_time;
1055 time(&long_time);
1056 localtime_r(&long_time, &t);
1057 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1058 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1059 t.tm_hour, t.tm_min, t.tm_sec);
1060 return buf;
1061 }
1063 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1064 return localtime_r(clock, res);
1065 }
1067 ////////////////////////////////////////////////////////////////////////////////
1068 // runtime exit support
1070 // Note: os::shutdown() might be called very early during initialization, or
1071 // called from signal handler. Before adding something to os::shutdown(), make
1072 // sure it is async-safe and can handle partially initialized VM.
1073 void os::shutdown() {
1075 // allow PerfMemory to attempt cleanup of any persistent resources
1076 perfMemory_exit();
1078 // needs to remove object in file system
1079 AttachListener::abort();
1081 // flush buffered output, finish log files
1082 ostream_abort();
1084 // Check for abort hook
1085 abort_hook_t abort_hook = Arguments::abort_hook();
1086 if (abort_hook != NULL) {
1087 abort_hook();
1088 }
1090 }
1092 // Note: os::abort() might be called very early during initialization, or
1093 // called from signal handler. Before adding something to os::abort(), make
1094 // sure it is async-safe and can handle partially initialized VM.
1095 void os::abort(bool dump_core) {
1096 os::shutdown();
1097 if (dump_core) {
1098 #ifndef PRODUCT
1099 fdStream out(defaultStream::output_fd());
1100 out.print_raw("Current thread is ");
1101 char buf[16];
1102 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1103 out.print_raw_cr(buf);
1104 out.print_raw_cr("Dumping core ...");
1105 #endif
1106 ::abort(); // dump core
1107 }
1109 ::exit(1);
1110 }
1112 // Die immediately, no exit hook, no abort hook, no cleanup.
1113 void os::die() {
1114 // _exit() on BsdThreads only kills current thread
1115 ::abort();
1116 }
1118 // unused on bsd for now.
1119 void os::set_error_file(const char *logfile) {}
1122 // This method is a copy of JDK's sysGetLastErrorString
1123 // from src/solaris/hpi/src/system_md.c
1125 size_t os::lasterror(char *buf, size_t len) {
1127 if (errno == 0) return 0;
1129 const char *s = ::strerror(errno);
1130 size_t n = ::strlen(s);
1131 if (n >= len) {
1132 n = len - 1;
1133 }
1134 ::strncpy(buf, s, n);
1135 buf[n] = '\0';
1136 return n;
1137 }
1139 // Information of current thread in variety of formats
1140 pid_t os::Bsd::gettid() {
1141 int retval = -1;
1143 #ifdef __APPLE__ //XNU kernel
1144 // despite the fact mach port is actually not a thread id use it
1145 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1146 retval = ::pthread_mach_thread_np(::pthread_self());
1147 guarantee(retval != 0, "just checking");
1148 return retval;
1150 #elif __FreeBSD__
1151 retval = syscall(SYS_thr_self);
1152 #elif __OpenBSD__
1153 retval = syscall(SYS_getthrid);
1154 #elif __NetBSD__
1155 retval = (pid_t) syscall(SYS__lwp_self);
1156 #endif
1158 if (retval == -1) {
1159 return getpid();
1160 }
1161 }
1163 intx os::current_thread_id() {
1164 #ifdef __APPLE__
1165 return (intx)::pthread_mach_thread_np(::pthread_self());
1166 #else
1167 return (intx)::pthread_self();
1168 #endif
1169 }
1171 int os::current_process_id() {
1173 // Under the old bsd thread library, bsd gives each thread
1174 // its own process id. Because of this each thread will return
1175 // a different pid if this method were to return the result
1176 // of getpid(2). Bsd provides no api that returns the pid
1177 // of the launcher thread for the vm. This implementation
1178 // returns a unique pid, the pid of the launcher thread
1179 // that starts the vm 'process'.
1181 // Under the NPTL, getpid() returns the same pid as the
1182 // launcher thread rather than a unique pid per thread.
1183 // Use gettid() if you want the old pre NPTL behaviour.
1185 // if you are looking for the result of a call to getpid() that
1186 // returns a unique pid for the calling thread, then look at the
1187 // OSThread::thread_id() method in osThread_bsd.hpp file
1189 return (int)(_initial_pid ? _initial_pid : getpid());
1190 }
1192 // DLL functions
1194 #define JNI_LIB_PREFIX "lib"
1195 #ifdef __APPLE__
1196 #define JNI_LIB_SUFFIX ".dylib"
1197 #else
1198 #define JNI_LIB_SUFFIX ".so"
1199 #endif
1201 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1203 // This must be hard coded because it's the system's temporary
1204 // directory not the java application's temp directory, ala java.io.tmpdir.
1205 #ifdef __APPLE__
1206 // macosx has a secure per-user temporary directory
1207 char temp_path_storage[PATH_MAX];
1208 const char* os::get_temp_directory() {
1209 static char *temp_path = NULL;
1210 if (temp_path == NULL) {
1211 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1212 if (pathSize == 0 || pathSize > PATH_MAX) {
1213 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1214 }
1215 temp_path = temp_path_storage;
1216 }
1217 return temp_path;
1218 }
1219 #else /* __APPLE__ */
1220 const char* os::get_temp_directory() { return "/tmp"; }
1221 #endif /* __APPLE__ */
1223 static bool file_exists(const char* filename) {
1224 struct stat statbuf;
1225 if (filename == NULL || strlen(filename) == 0) {
1226 return false;
1227 }
1228 return os::stat(filename, &statbuf) == 0;
1229 }
1231 bool os::dll_build_name(char* buffer, size_t buflen,
1232 const char* pname, const char* fname) {
1233 bool retval = false;
1234 // Copied from libhpi
1235 const size_t pnamelen = pname ? strlen(pname) : 0;
1237 // Return error on buffer overflow.
1238 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1239 return retval;
1240 }
1242 if (pnamelen == 0) {
1243 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1244 retval = true;
1245 } else if (strchr(pname, *os::path_separator()) != NULL) {
1246 int n;
1247 char** pelements = split_path(pname, &n);
1248 if (pelements == NULL) {
1249 return false;
1250 }
1251 for (int i = 0 ; i < n ; i++) {
1252 // Really shouldn't be NULL, but check can't hurt
1253 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1254 continue; // skip the empty path values
1255 }
1256 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1257 pelements[i], fname);
1258 if (file_exists(buffer)) {
1259 retval = true;
1260 break;
1261 }
1262 }
1263 // release the storage
1264 for (int i = 0 ; i < n ; i++) {
1265 if (pelements[i] != NULL) {
1266 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1267 }
1268 }
1269 if (pelements != NULL) {
1270 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1271 }
1272 } else {
1273 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1274 retval = true;
1275 }
1276 return retval;
1277 }
1279 // check if addr is inside libjvm.so
1280 bool os::address_is_in_vm(address addr) {
1281 static address libjvm_base_addr;
1282 Dl_info dlinfo;
1284 if (libjvm_base_addr == NULL) {
1285 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1286 libjvm_base_addr = (address)dlinfo.dli_fbase;
1287 }
1288 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1289 }
1291 if (dladdr((void *)addr, &dlinfo) != 0) {
1292 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1293 }
1295 return false;
1296 }
1299 #define MACH_MAXSYMLEN 256
1301 bool os::dll_address_to_function_name(address addr, char *buf,
1302 int buflen, int *offset) {
1303 // buf is not optional, but offset is optional
1304 assert(buf != NULL, "sanity check");
1306 Dl_info dlinfo;
1307 char localbuf[MACH_MAXSYMLEN];
1309 if (dladdr((void*)addr, &dlinfo) != 0) {
1310 // see if we have a matching symbol
1311 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1312 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1313 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1314 }
1315 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1316 return true;
1317 }
1318 // no matching symbol so try for just file info
1319 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1320 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1321 buf, buflen, offset, dlinfo.dli_fname)) {
1322 return true;
1323 }
1324 }
1326 // Handle non-dynamic manually:
1327 if (dlinfo.dli_fbase != NULL &&
1328 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1329 dlinfo.dli_fbase)) {
1330 if (!Decoder::demangle(localbuf, buf, buflen)) {
1331 jio_snprintf(buf, buflen, "%s", localbuf);
1332 }
1333 return true;
1334 }
1335 }
1336 buf[0] = '\0';
1337 if (offset != NULL) *offset = -1;
1338 return false;
1339 }
1341 // ported from solaris version
1342 bool os::dll_address_to_library_name(address addr, char* buf,
1343 int buflen, int* offset) {
1344 // buf is not optional, but offset is optional
1345 assert(buf != NULL, "sanity check");
1347 Dl_info dlinfo;
1349 if (dladdr((void*)addr, &dlinfo) != 0) {
1350 if (dlinfo.dli_fname != NULL) {
1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1352 }
1353 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1354 *offset = addr - (address)dlinfo.dli_fbase;
1355 }
1356 return true;
1357 }
1359 buf[0] = '\0';
1360 if (offset) *offset = -1;
1361 return false;
1362 }
1364 // Loads .dll/.so and
1365 // in case of error it checks if .dll/.so was built for the
1366 // same architecture as Hotspot is running on
1368 #ifdef __APPLE__
1369 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1370 void * result= ::dlopen(filename, RTLD_LAZY);
1371 if (result != NULL) {
1372 // Successful loading
1373 return result;
1374 }
1376 // Read system error message into ebuf
1377 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1378 ebuf[ebuflen-1]='\0';
1380 return NULL;
1381 }
1382 #else
1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1384 {
1385 void * result= ::dlopen(filename, RTLD_LAZY);
1386 if (result != NULL) {
1387 // Successful loading
1388 return result;
1389 }
1391 Elf32_Ehdr elf_head;
1393 // Read system error message into ebuf
1394 // It may or may not be overwritten below
1395 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1396 ebuf[ebuflen-1]='\0';
1397 int diag_msg_max_length=ebuflen-strlen(ebuf);
1398 char* diag_msg_buf=ebuf+strlen(ebuf);
1400 if (diag_msg_max_length==0) {
1401 // No more space in ebuf for additional diagnostics message
1402 return NULL;
1403 }
1406 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1408 if (file_descriptor < 0) {
1409 // Can't open library, report dlerror() message
1410 return NULL;
1411 }
1413 bool failed_to_read_elf_head=
1414 (sizeof(elf_head)!=
1415 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1417 ::close(file_descriptor);
1418 if (failed_to_read_elf_head) {
1419 // file i/o error - report dlerror() msg
1420 return NULL;
1421 }
1423 typedef struct {
1424 Elf32_Half code; // Actual value as defined in elf.h
1425 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1426 char elf_class; // 32 or 64 bit
1427 char endianess; // MSB or LSB
1428 char* name; // String representation
1429 } arch_t;
1431 #ifndef EM_486
1432 #define EM_486 6 /* Intel 80486 */
1433 #endif
1435 #ifndef EM_MIPS_RS3_LE
1436 #define EM_MIPS_RS3_LE 10 /* MIPS */
1437 #endif
1439 #ifndef EM_PPC64
1440 #define EM_PPC64 21 /* PowerPC64 */
1441 #endif
1443 #ifndef EM_S390
1444 #define EM_S390 22 /* IBM System/390 */
1445 #endif
1447 #ifndef EM_IA_64
1448 #define EM_IA_64 50 /* HP/Intel IA-64 */
1449 #endif
1451 #ifndef EM_X86_64
1452 #define EM_X86_64 62 /* AMD x86-64 */
1453 #endif
1455 static const arch_t arch_array[]={
1456 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1457 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1458 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1459 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1460 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1461 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1462 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1463 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1464 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1465 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1466 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1467 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1468 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1469 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1470 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1471 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1472 };
1474 #if (defined IA32)
1475 static Elf32_Half running_arch_code=EM_386;
1476 #elif (defined AMD64)
1477 static Elf32_Half running_arch_code=EM_X86_64;
1478 #elif (defined IA64)
1479 static Elf32_Half running_arch_code=EM_IA_64;
1480 #elif (defined __sparc) && (defined _LP64)
1481 static Elf32_Half running_arch_code=EM_SPARCV9;
1482 #elif (defined __sparc) && (!defined _LP64)
1483 static Elf32_Half running_arch_code=EM_SPARC;
1484 #elif (defined __powerpc64__)
1485 static Elf32_Half running_arch_code=EM_PPC64;
1486 #elif (defined __powerpc__)
1487 static Elf32_Half running_arch_code=EM_PPC;
1488 #elif (defined ARM)
1489 static Elf32_Half running_arch_code=EM_ARM;
1490 #elif (defined S390)
1491 static Elf32_Half running_arch_code=EM_S390;
1492 #elif (defined ALPHA)
1493 static Elf32_Half running_arch_code=EM_ALPHA;
1494 #elif (defined MIPSEL)
1495 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1496 #elif (defined PARISC)
1497 static Elf32_Half running_arch_code=EM_PARISC;
1498 #elif (defined MIPS)
1499 static Elf32_Half running_arch_code=EM_MIPS;
1500 #elif (defined M68K)
1501 static Elf32_Half running_arch_code=EM_68K;
1502 #else
1503 #error Method os::dll_load requires that one of following is defined:\
1504 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1505 #endif
1507 // Identify compatability class for VM's architecture and library's architecture
1508 // Obtain string descriptions for architectures
1510 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1511 int running_arch_index=-1;
1513 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1514 if (running_arch_code == arch_array[i].code) {
1515 running_arch_index = i;
1516 }
1517 if (lib_arch.code == arch_array[i].code) {
1518 lib_arch.compat_class = arch_array[i].compat_class;
1519 lib_arch.name = arch_array[i].name;
1520 }
1521 }
1523 assert(running_arch_index != -1,
1524 "Didn't find running architecture code (running_arch_code) in arch_array");
1525 if (running_arch_index == -1) {
1526 // Even though running architecture detection failed
1527 // we may still continue with reporting dlerror() message
1528 return NULL;
1529 }
1531 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1532 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1533 return NULL;
1534 }
1536 #ifndef S390
1537 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1539 return NULL;
1540 }
1541 #endif // !S390
1543 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1544 if ( lib_arch.name!=NULL ) {
1545 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1546 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1547 lib_arch.name, arch_array[running_arch_index].name);
1548 } else {
1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1550 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1551 lib_arch.code,
1552 arch_array[running_arch_index].name);
1553 }
1554 }
1556 return NULL;
1557 }
1558 #endif /* !__APPLE__ */
1560 void* os::get_default_process_handle() {
1561 #ifdef __APPLE__
1562 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1563 // to avoid finding unexpected symbols on second (or later)
1564 // loads of a library.
1565 return (void*)::dlopen(NULL, RTLD_FIRST);
1566 #else
1567 return (void*)::dlopen(NULL, RTLD_LAZY);
1568 #endif
1569 }
1571 // XXX: Do we need a lock around this as per Linux?
1572 void* os::dll_lookup(void* handle, const char* name) {
1573 return dlsym(handle, name);
1574 }
1577 static bool _print_ascii_file(const char* filename, outputStream* st) {
1578 int fd = ::open(filename, O_RDONLY);
1579 if (fd == -1) {
1580 return false;
1581 }
1583 char buf[32];
1584 int bytes;
1585 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1586 st->print_raw(buf, bytes);
1587 }
1589 ::close(fd);
1591 return true;
1592 }
1594 void os::print_dll_info(outputStream *st) {
1595 st->print_cr("Dynamic libraries:");
1596 #ifdef RTLD_DI_LINKMAP
1597 Dl_info dli;
1598 void *handle;
1599 Link_map *map;
1600 Link_map *p;
1602 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1603 dli.dli_fname == NULL) {
1604 st->print_cr("Error: Cannot print dynamic libraries.");
1605 return;
1606 }
1607 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1608 if (handle == NULL) {
1609 st->print_cr("Error: Cannot print dynamic libraries.");
1610 return;
1611 }
1612 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1613 if (map == NULL) {
1614 st->print_cr("Error: Cannot print dynamic libraries.");
1615 return;
1616 }
1618 while (map->l_prev != NULL)
1619 map = map->l_prev;
1621 while (map != NULL) {
1622 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1623 map = map->l_next;
1624 }
1626 dlclose(handle);
1627 #elif defined(__APPLE__)
1628 uint32_t count;
1629 uint32_t i;
1631 count = _dyld_image_count();
1632 for (i = 1; i < count; i++) {
1633 const char *name = _dyld_get_image_name(i);
1634 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1635 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1636 }
1637 #else
1638 st->print_cr("Error: Cannot print dynamic libraries.");
1639 #endif
1640 }
1642 void os::print_os_info_brief(outputStream* st) {
1643 st->print("Bsd");
1645 os::Posix::print_uname_info(st);
1646 }
1648 void os::print_os_info(outputStream* st) {
1649 st->print("OS:");
1650 st->print("Bsd");
1652 os::Posix::print_uname_info(st);
1654 os::Posix::print_rlimit_info(st);
1656 os::Posix::print_load_average(st);
1657 }
1659 void os::pd_print_cpu_info(outputStream* st) {
1660 // Nothing to do for now.
1661 }
1663 void os::print_memory_info(outputStream* st) {
1665 st->print("Memory:");
1666 st->print(" %dk page", os::vm_page_size()>>10);
1668 st->print(", physical " UINT64_FORMAT "k",
1669 os::physical_memory() >> 10);
1670 st->print("(" UINT64_FORMAT "k free)",
1671 os::available_memory() >> 10);
1672 st->cr();
1674 // meminfo
1675 st->print("\n/proc/meminfo:\n");
1676 _print_ascii_file("/proc/meminfo", st);
1677 st->cr();
1678 }
1680 void os::print_siginfo(outputStream* st, void* siginfo) {
1681 const siginfo_t* si = (const siginfo_t*)siginfo;
1683 os::Posix::print_siginfo_brief(st, si);
1685 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1686 UseSharedSpaces) {
1687 FileMapInfo* mapinfo = FileMapInfo::current_info();
1688 if (mapinfo->is_in_shared_space(si->si_addr)) {
1689 st->print("\n\nError accessing class data sharing archive." \
1690 " Mapped file inaccessible during execution, " \
1691 " possible disk/network problem.");
1692 }
1693 }
1694 st->cr();
1695 }
1698 static void print_signal_handler(outputStream* st, int sig,
1699 char* buf, size_t buflen);
1701 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1702 st->print_cr("Signal Handlers:");
1703 print_signal_handler(st, SIGSEGV, buf, buflen);
1704 print_signal_handler(st, SIGBUS , buf, buflen);
1705 print_signal_handler(st, SIGFPE , buf, buflen);
1706 print_signal_handler(st, SIGPIPE, buf, buflen);
1707 print_signal_handler(st, SIGXFSZ, buf, buflen);
1708 print_signal_handler(st, SIGILL , buf, buflen);
1709 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1710 print_signal_handler(st, SR_signum, buf, buflen);
1711 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1712 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1713 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1714 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1715 }
1717 static char saved_jvm_path[MAXPATHLEN] = {0};
1719 // Find the full path to the current module, libjvm
1720 void os::jvm_path(char *buf, jint buflen) {
1721 // Error checking.
1722 if (buflen < MAXPATHLEN) {
1723 assert(false, "must use a large-enough buffer");
1724 buf[0] = '\0';
1725 return;
1726 }
1727 // Lazy resolve the path to current module.
1728 if (saved_jvm_path[0] != 0) {
1729 strcpy(buf, saved_jvm_path);
1730 return;
1731 }
1733 char dli_fname[MAXPATHLEN];
1734 bool ret = dll_address_to_library_name(
1735 CAST_FROM_FN_PTR(address, os::jvm_path),
1736 dli_fname, sizeof(dli_fname), NULL);
1737 assert(ret, "cannot locate libjvm");
1738 char *rp = NULL;
1739 if (ret && dli_fname[0] != '\0') {
1740 rp = realpath(dli_fname, buf);
1741 }
1742 if (rp == NULL)
1743 return;
1745 if (Arguments::created_by_gamma_launcher()) {
1746 // Support for the gamma launcher. Typical value for buf is
1747 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1748 // the right place in the string, then assume we are installed in a JDK and
1749 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1750 // construct a path to the JVM being overridden.
1752 const char *p = buf + strlen(buf) - 1;
1753 for (int count = 0; p > buf && count < 5; ++count) {
1754 for (--p; p > buf && *p != '/'; --p)
1755 /* empty */ ;
1756 }
1758 if (strncmp(p, "/jre/lib/", 9) != 0) {
1759 // Look for JAVA_HOME in the environment.
1760 char* java_home_var = ::getenv("JAVA_HOME");
1761 if (java_home_var != NULL && java_home_var[0] != 0) {
1762 char* jrelib_p;
1763 int len;
1765 // Check the current module name "libjvm"
1766 p = strrchr(buf, '/');
1767 assert(strstr(p, "/libjvm") == p, "invalid library name");
1769 rp = realpath(java_home_var, buf);
1770 if (rp == NULL)
1771 return;
1773 // determine if this is a legacy image or modules image
1774 // modules image doesn't have "jre" subdirectory
1775 len = strlen(buf);
1776 jrelib_p = buf + len;
1778 // Add the appropriate library subdir
1779 snprintf(jrelib_p, buflen-len, "/jre/lib");
1780 if (0 != access(buf, F_OK)) {
1781 snprintf(jrelib_p, buflen-len, "/lib");
1782 }
1784 // Add the appropriate client or server subdir
1785 len = strlen(buf);
1786 jrelib_p = buf + len;
1787 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1788 if (0 != access(buf, F_OK)) {
1789 snprintf(jrelib_p, buflen-len, "");
1790 }
1792 // If the path exists within JAVA_HOME, add the JVM library name
1793 // to complete the path to JVM being overridden. Otherwise fallback
1794 // to the path to the current library.
1795 if (0 == access(buf, F_OK)) {
1796 // Use current module name "libjvm"
1797 len = strlen(buf);
1798 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1799 } else {
1800 // Fall back to path of current library
1801 rp = realpath(dli_fname, buf);
1802 if (rp == NULL)
1803 return;
1804 }
1805 }
1806 }
1807 }
1809 strcpy(saved_jvm_path, buf);
1810 }
1812 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1813 // no prefix required, not even "_"
1814 }
1816 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1817 // no suffix required
1818 }
1820 ////////////////////////////////////////////////////////////////////////////////
1821 // sun.misc.Signal support
1823 static volatile jint sigint_count = 0;
1825 static void
1826 UserHandler(int sig, void *siginfo, void *context) {
1827 // 4511530 - sem_post is serialized and handled by the manager thread. When
1828 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1829 // don't want to flood the manager thread with sem_post requests.
1830 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1831 return;
1833 // Ctrl-C is pressed during error reporting, likely because the error
1834 // handler fails to abort. Let VM die immediately.
1835 if (sig == SIGINT && is_error_reported()) {
1836 os::die();
1837 }
1839 os::signal_notify(sig);
1840 }
1842 void* os::user_handler() {
1843 return CAST_FROM_FN_PTR(void*, UserHandler);
1844 }
1846 extern "C" {
1847 typedef void (*sa_handler_t)(int);
1848 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1849 }
1851 void* os::signal(int signal_number, void* handler) {
1852 struct sigaction sigAct, oldSigAct;
1854 sigfillset(&(sigAct.sa_mask));
1855 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1856 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1858 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1859 // -1 means registration failed
1860 return (void *)-1;
1861 }
1863 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1864 }
1866 void os::signal_raise(int signal_number) {
1867 ::raise(signal_number);
1868 }
1870 /*
1871 * The following code is moved from os.cpp for making this
1872 * code platform specific, which it is by its very nature.
1873 */
1875 // Will be modified when max signal is changed to be dynamic
1876 int os::sigexitnum_pd() {
1877 return NSIG;
1878 }
1880 // a counter for each possible signal value
1881 static volatile jint pending_signals[NSIG+1] = { 0 };
1883 // Bsd(POSIX) specific hand shaking semaphore.
1884 #ifdef __APPLE__
1885 typedef semaphore_t os_semaphore_t;
1886 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1887 #define SEM_WAIT(sem) semaphore_wait(sem)
1888 #define SEM_POST(sem) semaphore_signal(sem)
1889 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1890 #else
1891 typedef sem_t os_semaphore_t;
1892 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1893 #define SEM_WAIT(sem) sem_wait(&sem)
1894 #define SEM_POST(sem) sem_post(&sem)
1895 #define SEM_DESTROY(sem) sem_destroy(&sem)
1896 #endif
1898 class Semaphore : public StackObj {
1899 public:
1900 Semaphore();
1901 ~Semaphore();
1902 void signal();
1903 void wait();
1904 bool trywait();
1905 bool timedwait(unsigned int sec, int nsec);
1906 private:
1907 jlong currenttime() const;
1908 os_semaphore_t _semaphore;
1909 };
1911 Semaphore::Semaphore() : _semaphore(0) {
1912 SEM_INIT(_semaphore, 0);
1913 }
1915 Semaphore::~Semaphore() {
1916 SEM_DESTROY(_semaphore);
1917 }
1919 void Semaphore::signal() {
1920 SEM_POST(_semaphore);
1921 }
1923 void Semaphore::wait() {
1924 SEM_WAIT(_semaphore);
1925 }
1927 jlong Semaphore::currenttime() const {
1928 struct timeval tv;
1929 gettimeofday(&tv, NULL);
1930 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1931 }
1933 #ifdef __APPLE__
1934 bool Semaphore::trywait() {
1935 return timedwait(0, 0);
1936 }
1938 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1939 kern_return_t kr = KERN_ABORTED;
1940 mach_timespec_t waitspec;
1941 waitspec.tv_sec = sec;
1942 waitspec.tv_nsec = nsec;
1944 jlong starttime = currenttime();
1946 kr = semaphore_timedwait(_semaphore, waitspec);
1947 while (kr == KERN_ABORTED) {
1948 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1950 jlong current = currenttime();
1951 jlong passedtime = current - starttime;
1953 if (passedtime >= totalwait) {
1954 waitspec.tv_sec = 0;
1955 waitspec.tv_nsec = 0;
1956 } else {
1957 jlong waittime = totalwait - (current - starttime);
1958 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1959 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1960 }
1962 kr = semaphore_timedwait(_semaphore, waitspec);
1963 }
1965 return kr == KERN_SUCCESS;
1966 }
1968 #else
1970 bool Semaphore::trywait() {
1971 return sem_trywait(&_semaphore) == 0;
1972 }
1974 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1975 struct timespec ts;
1976 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1978 while (1) {
1979 int result = sem_timedwait(&_semaphore, &ts);
1980 if (result == 0) {
1981 return true;
1982 } else if (errno == EINTR) {
1983 continue;
1984 } else if (errno == ETIMEDOUT) {
1985 return false;
1986 } else {
1987 return false;
1988 }
1989 }
1990 }
1992 #endif // __APPLE__
1994 static os_semaphore_t sig_sem;
1995 static Semaphore sr_semaphore;
1997 void os::signal_init_pd() {
1998 // Initialize signal structures
1999 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2001 // Initialize signal semaphore
2002 ::SEM_INIT(sig_sem, 0);
2003 }
2005 void os::signal_notify(int sig) {
2006 Atomic::inc(&pending_signals[sig]);
2007 ::SEM_POST(sig_sem);
2008 }
2010 static int check_pending_signals(bool wait) {
2011 Atomic::store(0, &sigint_count);
2012 for (;;) {
2013 for (int i = 0; i < NSIG + 1; i++) {
2014 jint n = pending_signals[i];
2015 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2016 return i;
2017 }
2018 }
2019 if (!wait) {
2020 return -1;
2021 }
2022 JavaThread *thread = JavaThread::current();
2023 ThreadBlockInVM tbivm(thread);
2025 bool threadIsSuspended;
2026 do {
2027 thread->set_suspend_equivalent();
2028 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2029 ::SEM_WAIT(sig_sem);
2031 // were we externally suspended while we were waiting?
2032 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2033 if (threadIsSuspended) {
2034 //
2035 // The semaphore has been incremented, but while we were waiting
2036 // another thread suspended us. We don't want to continue running
2037 // while suspended because that would surprise the thread that
2038 // suspended us.
2039 //
2040 ::SEM_POST(sig_sem);
2042 thread->java_suspend_self();
2043 }
2044 } while (threadIsSuspended);
2045 }
2046 }
2048 int os::signal_lookup() {
2049 return check_pending_signals(false);
2050 }
2052 int os::signal_wait() {
2053 return check_pending_signals(true);
2054 }
2056 ////////////////////////////////////////////////////////////////////////////////
2057 // Virtual Memory
2059 int os::vm_page_size() {
2060 // Seems redundant as all get out
2061 assert(os::Bsd::page_size() != -1, "must call os::init");
2062 return os::Bsd::page_size();
2063 }
2065 // Solaris allocates memory by pages.
2066 int os::vm_allocation_granularity() {
2067 assert(os::Bsd::page_size() != -1, "must call os::init");
2068 return os::Bsd::page_size();
2069 }
2071 // Rationale behind this function:
2072 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2073 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2074 // samples for JITted code. Here we create private executable mapping over the code cache
2075 // and then we can use standard (well, almost, as mapping can change) way to provide
2076 // info for the reporting script by storing timestamp and location of symbol
2077 void bsd_wrap_code(char* base, size_t size) {
2078 static volatile jint cnt = 0;
2080 if (!UseOprofile) {
2081 return;
2082 }
2084 char buf[PATH_MAX + 1];
2085 int num = Atomic::add(1, &cnt);
2087 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2088 os::get_temp_directory(), os::current_process_id(), num);
2089 unlink(buf);
2091 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2093 if (fd != -1) {
2094 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2095 if (rv != (off_t)-1) {
2096 if (::write(fd, "", 1) == 1) {
2097 mmap(base, size,
2098 PROT_READ|PROT_WRITE|PROT_EXEC,
2099 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2100 }
2101 }
2102 ::close(fd);
2103 unlink(buf);
2104 }
2105 }
2107 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2108 int err) {
2109 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2110 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2111 strerror(err), err);
2112 }
2114 // NOTE: Bsd kernel does not really reserve the pages for us.
2115 // All it does is to check if there are enough free pages
2116 // left at the time of mmap(). This could be a potential
2117 // problem.
2118 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2119 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2120 #ifdef __OpenBSD__
2121 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2122 if (::mprotect(addr, size, prot) == 0) {
2123 return true;
2124 }
2125 #else
2126 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2127 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2128 if (res != (uintptr_t) MAP_FAILED) {
2129 return true;
2130 }
2131 #endif
2133 // Warn about any commit errors we see in non-product builds just
2134 // in case mmap() doesn't work as described on the man page.
2135 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2137 return false;
2138 }
2140 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2141 bool exec) {
2142 // alignment_hint is ignored on this OS
2143 return pd_commit_memory(addr, size, exec);
2144 }
2146 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2147 const char* mesg) {
2148 assert(mesg != NULL, "mesg must be specified");
2149 if (!pd_commit_memory(addr, size, exec)) {
2150 // add extra info in product mode for vm_exit_out_of_memory():
2151 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2152 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2153 }
2154 }
2156 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2157 size_t alignment_hint, bool exec,
2158 const char* mesg) {
2159 // alignment_hint is ignored on this OS
2160 pd_commit_memory_or_exit(addr, size, exec, mesg);
2161 }
2163 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2164 }
2166 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2167 ::madvise(addr, bytes, MADV_DONTNEED);
2168 }
2170 void os::numa_make_global(char *addr, size_t bytes) {
2171 }
2173 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2174 }
2176 bool os::numa_topology_changed() { return false; }
2178 size_t os::numa_get_groups_num() {
2179 return 1;
2180 }
2182 int os::numa_get_group_id() {
2183 return 0;
2184 }
2186 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2187 if (size > 0) {
2188 ids[0] = 0;
2189 return 1;
2190 }
2191 return 0;
2192 }
2194 bool os::get_page_info(char *start, page_info* info) {
2195 return false;
2196 }
2198 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2199 return end;
2200 }
2203 bool os::pd_uncommit_memory(char* addr, size_t size) {
2204 #ifdef __OpenBSD__
2205 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2206 return ::mprotect(addr, size, PROT_NONE) == 0;
2207 #else
2208 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2209 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2210 return res != (uintptr_t) MAP_FAILED;
2211 #endif
2212 }
2214 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2215 return os::commit_memory(addr, size, !ExecMem);
2216 }
2218 // If this is a growable mapping, remove the guard pages entirely by
2219 // munmap()ping them. If not, just call uncommit_memory().
2220 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2221 return os::uncommit_memory(addr, size);
2222 }
2224 static address _highest_vm_reserved_address = NULL;
2226 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2227 // at 'requested_addr'. If there are existing memory mappings at the same
2228 // location, however, they will be overwritten. If 'fixed' is false,
2229 // 'requested_addr' is only treated as a hint, the return value may or
2230 // may not start from the requested address. Unlike Bsd mmap(), this
2231 // function returns NULL to indicate failure.
2232 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2233 char * addr;
2234 int flags;
2236 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2237 if (fixed) {
2238 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2239 flags |= MAP_FIXED;
2240 }
2242 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2243 // touch an uncommitted page. Otherwise, the read/write might
2244 // succeed if we have enough swap space to back the physical page.
2245 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2246 flags, -1, 0);
2248 if (addr != MAP_FAILED) {
2249 // anon_mmap() should only get called during VM initialization,
2250 // don't need lock (actually we can skip locking even it can be called
2251 // from multiple threads, because _highest_vm_reserved_address is just a
2252 // hint about the upper limit of non-stack memory regions.)
2253 if ((address)addr + bytes > _highest_vm_reserved_address) {
2254 _highest_vm_reserved_address = (address)addr + bytes;
2255 }
2256 }
2258 return addr == MAP_FAILED ? NULL : addr;
2259 }
2261 // Don't update _highest_vm_reserved_address, because there might be memory
2262 // regions above addr + size. If so, releasing a memory region only creates
2263 // a hole in the address space, it doesn't help prevent heap-stack collision.
2264 //
2265 static int anon_munmap(char * addr, size_t size) {
2266 return ::munmap(addr, size) == 0;
2267 }
2269 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2270 size_t alignment_hint) {
2271 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2272 }
2274 bool os::pd_release_memory(char* addr, size_t size) {
2275 return anon_munmap(addr, size);
2276 }
2278 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2279 // Bsd wants the mprotect address argument to be page aligned.
2280 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2282 // According to SUSv3, mprotect() should only be used with mappings
2283 // established by mmap(), and mmap() always maps whole pages. Unaligned
2284 // 'addr' likely indicates problem in the VM (e.g. trying to change
2285 // protection of malloc'ed or statically allocated memory). Check the
2286 // caller if you hit this assert.
2287 assert(addr == bottom, "sanity check");
2289 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2290 return ::mprotect(bottom, size, prot) == 0;
2291 }
2293 // Set protections specified
2294 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2295 bool is_committed) {
2296 unsigned int p = 0;
2297 switch (prot) {
2298 case MEM_PROT_NONE: p = PROT_NONE; break;
2299 case MEM_PROT_READ: p = PROT_READ; break;
2300 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2301 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2302 default:
2303 ShouldNotReachHere();
2304 }
2305 // is_committed is unused.
2306 return bsd_mprotect(addr, bytes, p);
2307 }
2309 bool os::guard_memory(char* addr, size_t size) {
2310 return bsd_mprotect(addr, size, PROT_NONE);
2311 }
2313 bool os::unguard_memory(char* addr, size_t size) {
2314 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2315 }
2317 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2318 return false;
2319 }
2321 // Large page support
2323 static size_t _large_page_size = 0;
2325 void os::large_page_init() {
2326 }
2329 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2330 fatal("This code is not used or maintained.");
2332 // "exec" is passed in but not used. Creating the shared image for
2333 // the code cache doesn't have an SHM_X executable permission to check.
2334 assert(UseLargePages && UseSHM, "only for SHM large pages");
2336 key_t key = IPC_PRIVATE;
2337 char *addr;
2339 bool warn_on_failure = UseLargePages &&
2340 (!FLAG_IS_DEFAULT(UseLargePages) ||
2341 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2342 );
2343 char msg[128];
2345 // Create a large shared memory region to attach to based on size.
2346 // Currently, size is the total size of the heap
2347 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2348 if (shmid == -1) {
2349 // Possible reasons for shmget failure:
2350 // 1. shmmax is too small for Java heap.
2351 // > check shmmax value: cat /proc/sys/kernel/shmmax
2352 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2353 // 2. not enough large page memory.
2354 // > check available large pages: cat /proc/meminfo
2355 // > increase amount of large pages:
2356 // echo new_value > /proc/sys/vm/nr_hugepages
2357 // Note 1: different Bsd may use different name for this property,
2358 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2359 // Note 2: it's possible there's enough physical memory available but
2360 // they are so fragmented after a long run that they can't
2361 // coalesce into large pages. Try to reserve large pages when
2362 // the system is still "fresh".
2363 if (warn_on_failure) {
2364 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2365 warning(msg);
2366 }
2367 return NULL;
2368 }
2370 // attach to the region
2371 addr = (char*)shmat(shmid, req_addr, 0);
2372 int err = errno;
2374 // Remove shmid. If shmat() is successful, the actual shared memory segment
2375 // will be deleted when it's detached by shmdt() or when the process
2376 // terminates. If shmat() is not successful this will remove the shared
2377 // segment immediately.
2378 shmctl(shmid, IPC_RMID, NULL);
2380 if ((intptr_t)addr == -1) {
2381 if (warn_on_failure) {
2382 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2383 warning(msg);
2384 }
2385 return NULL;
2386 }
2388 // The memory is committed
2389 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2391 return addr;
2392 }
2394 bool os::release_memory_special(char* base, size_t bytes) {
2395 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2396 // detaching the SHM segment will also delete it, see reserve_memory_special()
2397 int rslt = shmdt(base);
2398 if (rslt == 0) {
2399 tkr.record((address)base, bytes);
2400 return true;
2401 } else {
2402 tkr.discard();
2403 return false;
2404 }
2406 }
2408 size_t os::large_page_size() {
2409 return _large_page_size;
2410 }
2412 // HugeTLBFS allows application to commit large page memory on demand;
2413 // with SysV SHM the entire memory region must be allocated as shared
2414 // memory.
2415 bool os::can_commit_large_page_memory() {
2416 return UseHugeTLBFS;
2417 }
2419 bool os::can_execute_large_page_memory() {
2420 return UseHugeTLBFS;
2421 }
2423 // Reserve memory at an arbitrary address, only if that area is
2424 // available (and not reserved for something else).
2426 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2427 const int max_tries = 10;
2428 char* base[max_tries];
2429 size_t size[max_tries];
2430 const size_t gap = 0x000000;
2432 // Assert only that the size is a multiple of the page size, since
2433 // that's all that mmap requires, and since that's all we really know
2434 // about at this low abstraction level. If we need higher alignment,
2435 // we can either pass an alignment to this method or verify alignment
2436 // in one of the methods further up the call chain. See bug 5044738.
2437 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2439 // Repeatedly allocate blocks until the block is allocated at the
2440 // right spot. Give up after max_tries. Note that reserve_memory() will
2441 // automatically update _highest_vm_reserved_address if the call is
2442 // successful. The variable tracks the highest memory address every reserved
2443 // by JVM. It is used to detect heap-stack collision if running with
2444 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2445 // space than needed, it could confuse the collision detecting code. To
2446 // solve the problem, save current _highest_vm_reserved_address and
2447 // calculate the correct value before return.
2448 address old_highest = _highest_vm_reserved_address;
2450 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2451 // if kernel honors the hint then we can return immediately.
2452 char * addr = anon_mmap(requested_addr, bytes, false);
2453 if (addr == requested_addr) {
2454 return requested_addr;
2455 }
2457 if (addr != NULL) {
2458 // mmap() is successful but it fails to reserve at the requested address
2459 anon_munmap(addr, bytes);
2460 }
2462 int i;
2463 for (i = 0; i < max_tries; ++i) {
2464 base[i] = reserve_memory(bytes);
2466 if (base[i] != NULL) {
2467 // Is this the block we wanted?
2468 if (base[i] == requested_addr) {
2469 size[i] = bytes;
2470 break;
2471 }
2473 // Does this overlap the block we wanted? Give back the overlapped
2474 // parts and try again.
2476 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2477 if (top_overlap >= 0 && top_overlap < bytes) {
2478 unmap_memory(base[i], top_overlap);
2479 base[i] += top_overlap;
2480 size[i] = bytes - top_overlap;
2481 } else {
2482 size_t bottom_overlap = base[i] + bytes - requested_addr;
2483 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2484 unmap_memory(requested_addr, bottom_overlap);
2485 size[i] = bytes - bottom_overlap;
2486 } else {
2487 size[i] = bytes;
2488 }
2489 }
2490 }
2491 }
2493 // Give back the unused reserved pieces.
2495 for (int j = 0; j < i; ++j) {
2496 if (base[j] != NULL) {
2497 unmap_memory(base[j], size[j]);
2498 }
2499 }
2501 if (i < max_tries) {
2502 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2503 return requested_addr;
2504 } else {
2505 _highest_vm_reserved_address = old_highest;
2506 return NULL;
2507 }
2508 }
2510 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2511 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2512 }
2514 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2515 // Solaris uses poll(), bsd uses park().
2516 // Poll() is likely a better choice, assuming that Thread.interrupt()
2517 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2518 // SIGSEGV, see 4355769.
2520 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2521 assert(thread == Thread::current(), "thread consistency check");
2523 ParkEvent * const slp = thread->_SleepEvent ;
2524 slp->reset() ;
2525 OrderAccess::fence() ;
2527 if (interruptible) {
2528 jlong prevtime = javaTimeNanos();
2530 for (;;) {
2531 if (os::is_interrupted(thread, true)) {
2532 return OS_INTRPT;
2533 }
2535 jlong newtime = javaTimeNanos();
2537 if (newtime - prevtime < 0) {
2538 // time moving backwards, should only happen if no monotonic clock
2539 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2540 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2541 } else {
2542 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2543 }
2545 if(millis <= 0) {
2546 return OS_OK;
2547 }
2549 prevtime = newtime;
2551 {
2552 assert(thread->is_Java_thread(), "sanity check");
2553 JavaThread *jt = (JavaThread *) thread;
2554 ThreadBlockInVM tbivm(jt);
2555 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2557 jt->set_suspend_equivalent();
2558 // cleared by handle_special_suspend_equivalent_condition() or
2559 // java_suspend_self() via check_and_wait_while_suspended()
2561 slp->park(millis);
2563 // were we externally suspended while we were waiting?
2564 jt->check_and_wait_while_suspended();
2565 }
2566 }
2567 } else {
2568 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2569 jlong prevtime = javaTimeNanos();
2571 for (;;) {
2572 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2573 // the 1st iteration ...
2574 jlong newtime = javaTimeNanos();
2576 if (newtime - prevtime < 0) {
2577 // time moving backwards, should only happen if no monotonic clock
2578 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2579 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2580 } else {
2581 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2582 }
2584 if(millis <= 0) break ;
2586 prevtime = newtime;
2587 slp->park(millis);
2588 }
2589 return OS_OK ;
2590 }
2591 }
2593 int os::naked_sleep() {
2594 // %% make the sleep time an integer flag. for now use 1 millisec.
2595 return os::sleep(Thread::current(), 1, false);
2596 }
2598 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2599 void os::infinite_sleep() {
2600 while (true) { // sleep forever ...
2601 ::sleep(100); // ... 100 seconds at a time
2602 }
2603 }
2605 // Used to convert frequent JVM_Yield() to nops
2606 bool os::dont_yield() {
2607 return DontYieldALot;
2608 }
2610 void os::yield() {
2611 sched_yield();
2612 }
2614 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2616 void os::yield_all(int attempts) {
2617 // Yields to all threads, including threads with lower priorities
2618 // Threads on Bsd are all with same priority. The Solaris style
2619 // os::yield_all() with nanosleep(1ms) is not necessary.
2620 sched_yield();
2621 }
2623 // Called from the tight loops to possibly influence time-sharing heuristics
2624 void os::loop_breaker(int attempts) {
2625 os::yield_all(attempts);
2626 }
2628 ////////////////////////////////////////////////////////////////////////////////
2629 // thread priority support
2631 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2632 // only supports dynamic priority, static priority must be zero. For real-time
2633 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2634 // However, for large multi-threaded applications, SCHED_RR is not only slower
2635 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2636 // of 5 runs - Sep 2005).
2637 //
2638 // The following code actually changes the niceness of kernel-thread/LWP. It
2639 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2640 // not the entire user process, and user level threads are 1:1 mapped to kernel
2641 // threads. It has always been the case, but could change in the future. For
2642 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2643 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2645 #if !defined(__APPLE__)
2646 int os::java_to_os_priority[CriticalPriority + 1] = {
2647 19, // 0 Entry should never be used
2649 0, // 1 MinPriority
2650 3, // 2
2651 6, // 3
2653 10, // 4
2654 15, // 5 NormPriority
2655 18, // 6
2657 21, // 7
2658 25, // 8
2659 28, // 9 NearMaxPriority
2661 31, // 10 MaxPriority
2663 31 // 11 CriticalPriority
2664 };
2665 #else
2666 /* Using Mach high-level priority assignments */
2667 int os::java_to_os_priority[CriticalPriority + 1] = {
2668 0, // 0 Entry should never be used (MINPRI_USER)
2670 27, // 1 MinPriority
2671 28, // 2
2672 29, // 3
2674 30, // 4
2675 31, // 5 NormPriority (BASEPRI_DEFAULT)
2676 32, // 6
2678 33, // 7
2679 34, // 8
2680 35, // 9 NearMaxPriority
2682 36, // 10 MaxPriority
2684 36 // 11 CriticalPriority
2685 };
2686 #endif
2688 static int prio_init() {
2689 if (ThreadPriorityPolicy == 1) {
2690 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2691 // if effective uid is not root. Perhaps, a more elegant way of doing
2692 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2693 if (geteuid() != 0) {
2694 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2695 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2696 }
2697 ThreadPriorityPolicy = 0;
2698 }
2699 }
2700 if (UseCriticalJavaThreadPriority) {
2701 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2702 }
2703 return 0;
2704 }
2706 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2707 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2709 #ifdef __OpenBSD__
2710 // OpenBSD pthread_setprio starves low priority threads
2711 return OS_OK;
2712 #elif defined(__FreeBSD__)
2713 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2714 #elif defined(__APPLE__) || defined(__NetBSD__)
2715 struct sched_param sp;
2716 int policy;
2717 pthread_t self = pthread_self();
2719 if (pthread_getschedparam(self, &policy, &sp) != 0)
2720 return OS_ERR;
2722 sp.sched_priority = newpri;
2723 if (pthread_setschedparam(self, policy, &sp) != 0)
2724 return OS_ERR;
2726 return OS_OK;
2727 #else
2728 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2729 return (ret == 0) ? OS_OK : OS_ERR;
2730 #endif
2731 }
2733 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2734 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2735 *priority_ptr = java_to_os_priority[NormPriority];
2736 return OS_OK;
2737 }
2739 errno = 0;
2740 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2741 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2742 #elif defined(__APPLE__) || defined(__NetBSD__)
2743 int policy;
2744 struct sched_param sp;
2746 pthread_getschedparam(pthread_self(), &policy, &sp);
2747 *priority_ptr = sp.sched_priority;
2748 #else
2749 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2750 #endif
2751 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2752 }
2754 // Hint to the underlying OS that a task switch would not be good.
2755 // Void return because it's a hint and can fail.
2756 void os::hint_no_preempt() {}
2758 ////////////////////////////////////////////////////////////////////////////////
2759 // suspend/resume support
2761 // the low-level signal-based suspend/resume support is a remnant from the
2762 // old VM-suspension that used to be for java-suspension, safepoints etc,
2763 // within hotspot. Now there is a single use-case for this:
2764 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2765 // that runs in the watcher thread.
2766 // The remaining code is greatly simplified from the more general suspension
2767 // code that used to be used.
2768 //
2769 // The protocol is quite simple:
2770 // - suspend:
2771 // - sends a signal to the target thread
2772 // - polls the suspend state of the osthread using a yield loop
2773 // - target thread signal handler (SR_handler) sets suspend state
2774 // and blocks in sigsuspend until continued
2775 // - resume:
2776 // - sets target osthread state to continue
2777 // - sends signal to end the sigsuspend loop in the SR_handler
2778 //
2779 // Note that the SR_lock plays no role in this suspend/resume protocol.
2780 //
2782 static void resume_clear_context(OSThread *osthread) {
2783 osthread->set_ucontext(NULL);
2784 osthread->set_siginfo(NULL);
2785 }
2787 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2788 osthread->set_ucontext(context);
2789 osthread->set_siginfo(siginfo);
2790 }
2792 //
2793 // Handler function invoked when a thread's execution is suspended or
2794 // resumed. We have to be careful that only async-safe functions are
2795 // called here (Note: most pthread functions are not async safe and
2796 // should be avoided.)
2797 //
2798 // Note: sigwait() is a more natural fit than sigsuspend() from an
2799 // interface point of view, but sigwait() prevents the signal hander
2800 // from being run. libpthread would get very confused by not having
2801 // its signal handlers run and prevents sigwait()'s use with the
2802 // mutex granting granting signal.
2803 //
2804 // Currently only ever called on the VMThread or JavaThread
2805 //
2806 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2807 // Save and restore errno to avoid confusing native code with EINTR
2808 // after sigsuspend.
2809 int old_errno = errno;
2811 Thread* thread = Thread::current();
2812 OSThread* osthread = thread->osthread();
2813 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2815 os::SuspendResume::State current = osthread->sr.state();
2816 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2817 suspend_save_context(osthread, siginfo, context);
2819 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2820 os::SuspendResume::State state = osthread->sr.suspended();
2821 if (state == os::SuspendResume::SR_SUSPENDED) {
2822 sigset_t suspend_set; // signals for sigsuspend()
2824 // get current set of blocked signals and unblock resume signal
2825 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2826 sigdelset(&suspend_set, SR_signum);
2828 sr_semaphore.signal();
2829 // wait here until we are resumed
2830 while (1) {
2831 sigsuspend(&suspend_set);
2833 os::SuspendResume::State result = osthread->sr.running();
2834 if (result == os::SuspendResume::SR_RUNNING) {
2835 sr_semaphore.signal();
2836 break;
2837 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2838 ShouldNotReachHere();
2839 }
2840 }
2842 } else if (state == os::SuspendResume::SR_RUNNING) {
2843 // request was cancelled, continue
2844 } else {
2845 ShouldNotReachHere();
2846 }
2848 resume_clear_context(osthread);
2849 } else if (current == os::SuspendResume::SR_RUNNING) {
2850 // request was cancelled, continue
2851 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2852 // ignore
2853 } else {
2854 // ignore
2855 }
2857 errno = old_errno;
2858 }
2861 static int SR_initialize() {
2862 struct sigaction act;
2863 char *s;
2864 /* Get signal number to use for suspend/resume */
2865 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2866 int sig = ::strtol(s, 0, 10);
2867 if (sig > 0 || sig < NSIG) {
2868 SR_signum = sig;
2869 }
2870 }
2872 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2873 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2875 sigemptyset(&SR_sigset);
2876 sigaddset(&SR_sigset, SR_signum);
2878 /* Set up signal handler for suspend/resume */
2879 act.sa_flags = SA_RESTART|SA_SIGINFO;
2880 act.sa_handler = (void (*)(int)) SR_handler;
2882 // SR_signum is blocked by default.
2883 // 4528190 - We also need to block pthread restart signal (32 on all
2884 // supported Bsd platforms). Note that BsdThreads need to block
2885 // this signal for all threads to work properly. So we don't have
2886 // to use hard-coded signal number when setting up the mask.
2887 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2889 if (sigaction(SR_signum, &act, 0) == -1) {
2890 return -1;
2891 }
2893 // Save signal flag
2894 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2895 return 0;
2896 }
2898 static int sr_notify(OSThread* osthread) {
2899 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2900 assert_status(status == 0, status, "pthread_kill");
2901 return status;
2902 }
2904 // "Randomly" selected value for how long we want to spin
2905 // before bailing out on suspending a thread, also how often
2906 // we send a signal to a thread we want to resume
2907 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2908 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2910 // returns true on success and false on error - really an error is fatal
2911 // but this seems the normal response to library errors
2912 static bool do_suspend(OSThread* osthread) {
2913 assert(osthread->sr.is_running(), "thread should be running");
2914 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2916 // mark as suspended and send signal
2917 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2918 // failed to switch, state wasn't running?
2919 ShouldNotReachHere();
2920 return false;
2921 }
2923 if (sr_notify(osthread) != 0) {
2924 ShouldNotReachHere();
2925 }
2927 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2928 while (true) {
2929 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2930 break;
2931 } else {
2932 // timeout
2933 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2934 if (cancelled == os::SuspendResume::SR_RUNNING) {
2935 return false;
2936 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2937 // make sure that we consume the signal on the semaphore as well
2938 sr_semaphore.wait();
2939 break;
2940 } else {
2941 ShouldNotReachHere();
2942 return false;
2943 }
2944 }
2945 }
2947 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2948 return true;
2949 }
2951 static void do_resume(OSThread* osthread) {
2952 assert(osthread->sr.is_suspended(), "thread should be suspended");
2953 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2955 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2956 // failed to switch to WAKEUP_REQUEST
2957 ShouldNotReachHere();
2958 return;
2959 }
2961 while (true) {
2962 if (sr_notify(osthread) == 0) {
2963 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2964 if (osthread->sr.is_running()) {
2965 return;
2966 }
2967 }
2968 } else {
2969 ShouldNotReachHere();
2970 }
2971 }
2973 guarantee(osthread->sr.is_running(), "Must be running!");
2974 }
2976 ////////////////////////////////////////////////////////////////////////////////
2977 // interrupt support
2979 void os::interrupt(Thread* thread) {
2980 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2981 "possibility of dangling Thread pointer");
2983 OSThread* osthread = thread->osthread();
2985 if (!osthread->interrupted()) {
2986 osthread->set_interrupted(true);
2987 // More than one thread can get here with the same value of osthread,
2988 // resulting in multiple notifications. We do, however, want the store
2989 // to interrupted() to be visible to other threads before we execute unpark().
2990 OrderAccess::fence();
2991 ParkEvent * const slp = thread->_SleepEvent ;
2992 if (slp != NULL) slp->unpark() ;
2993 }
2995 // For JSR166. Unpark even if interrupt status already was set
2996 if (thread->is_Java_thread())
2997 ((JavaThread*)thread)->parker()->unpark();
2999 ParkEvent * ev = thread->_ParkEvent ;
3000 if (ev != NULL) ev->unpark() ;
3002 }
3004 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3005 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3006 "possibility of dangling Thread pointer");
3008 OSThread* osthread = thread->osthread();
3010 bool interrupted = osthread->interrupted();
3012 if (interrupted && clear_interrupted) {
3013 osthread->set_interrupted(false);
3014 // consider thread->_SleepEvent->reset() ... optional optimization
3015 }
3017 return interrupted;
3018 }
3020 ///////////////////////////////////////////////////////////////////////////////////
3021 // signal handling (except suspend/resume)
3023 // This routine may be used by user applications as a "hook" to catch signals.
3024 // The user-defined signal handler must pass unrecognized signals to this
3025 // routine, and if it returns true (non-zero), then the signal handler must
3026 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3027 // routine will never retun false (zero), but instead will execute a VM panic
3028 // routine kill the process.
3029 //
3030 // If this routine returns false, it is OK to call it again. This allows
3031 // the user-defined signal handler to perform checks either before or after
3032 // the VM performs its own checks. Naturally, the user code would be making
3033 // a serious error if it tried to handle an exception (such as a null check
3034 // or breakpoint) that the VM was generating for its own correct operation.
3035 //
3036 // This routine may recognize any of the following kinds of signals:
3037 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3038 // It should be consulted by handlers for any of those signals.
3039 //
3040 // The caller of this routine must pass in the three arguments supplied
3041 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3042 // field of the structure passed to sigaction(). This routine assumes that
3043 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3044 //
3045 // Note that the VM will print warnings if it detects conflicting signal
3046 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3047 //
3048 extern "C" JNIEXPORT int
3049 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3050 void* ucontext, int abort_if_unrecognized);
3052 void signalHandler(int sig, siginfo_t* info, void* uc) {
3053 assert(info != NULL && uc != NULL, "it must be old kernel");
3054 int orig_errno = errno; // Preserve errno value over signal handler.
3055 JVM_handle_bsd_signal(sig, info, uc, true);
3056 errno = orig_errno;
3057 }
3060 // This boolean allows users to forward their own non-matching signals
3061 // to JVM_handle_bsd_signal, harmlessly.
3062 bool os::Bsd::signal_handlers_are_installed = false;
3064 // For signal-chaining
3065 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3066 unsigned int os::Bsd::sigs = 0;
3067 bool os::Bsd::libjsig_is_loaded = false;
3068 typedef struct sigaction *(*get_signal_t)(int);
3069 get_signal_t os::Bsd::get_signal_action = NULL;
3071 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3072 struct sigaction *actp = NULL;
3074 if (libjsig_is_loaded) {
3075 // Retrieve the old signal handler from libjsig
3076 actp = (*get_signal_action)(sig);
3077 }
3078 if (actp == NULL) {
3079 // Retrieve the preinstalled signal handler from jvm
3080 actp = get_preinstalled_handler(sig);
3081 }
3083 return actp;
3084 }
3086 static bool call_chained_handler(struct sigaction *actp, int sig,
3087 siginfo_t *siginfo, void *context) {
3088 // Call the old signal handler
3089 if (actp->sa_handler == SIG_DFL) {
3090 // It's more reasonable to let jvm treat it as an unexpected exception
3091 // instead of taking the default action.
3092 return false;
3093 } else if (actp->sa_handler != SIG_IGN) {
3094 if ((actp->sa_flags & SA_NODEFER) == 0) {
3095 // automaticlly block the signal
3096 sigaddset(&(actp->sa_mask), sig);
3097 }
3099 sa_handler_t hand;
3100 sa_sigaction_t sa;
3101 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3102 // retrieve the chained handler
3103 if (siginfo_flag_set) {
3104 sa = actp->sa_sigaction;
3105 } else {
3106 hand = actp->sa_handler;
3107 }
3109 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3110 actp->sa_handler = SIG_DFL;
3111 }
3113 // try to honor the signal mask
3114 sigset_t oset;
3115 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3117 // call into the chained handler
3118 if (siginfo_flag_set) {
3119 (*sa)(sig, siginfo, context);
3120 } else {
3121 (*hand)(sig);
3122 }
3124 // restore the signal mask
3125 pthread_sigmask(SIG_SETMASK, &oset, 0);
3126 }
3127 // Tell jvm's signal handler the signal is taken care of.
3128 return true;
3129 }
3131 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3132 bool chained = false;
3133 // signal-chaining
3134 if (UseSignalChaining) {
3135 struct sigaction *actp = get_chained_signal_action(sig);
3136 if (actp != NULL) {
3137 chained = call_chained_handler(actp, sig, siginfo, context);
3138 }
3139 }
3140 return chained;
3141 }
3143 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3144 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3145 return &sigact[sig];
3146 }
3147 return NULL;
3148 }
3150 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3151 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3152 sigact[sig] = oldAct;
3153 sigs |= (unsigned int)1 << sig;
3154 }
3156 // for diagnostic
3157 int os::Bsd::sigflags[MAXSIGNUM];
3159 int os::Bsd::get_our_sigflags(int sig) {
3160 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3161 return sigflags[sig];
3162 }
3164 void os::Bsd::set_our_sigflags(int sig, int flags) {
3165 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3166 sigflags[sig] = flags;
3167 }
3169 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3170 // Check for overwrite.
3171 struct sigaction oldAct;
3172 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3174 void* oldhand = oldAct.sa_sigaction
3175 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3176 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3177 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3178 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3179 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3180 if (AllowUserSignalHandlers || !set_installed) {
3181 // Do not overwrite; user takes responsibility to forward to us.
3182 return;
3183 } else if (UseSignalChaining) {
3184 // save the old handler in jvm
3185 save_preinstalled_handler(sig, oldAct);
3186 // libjsig also interposes the sigaction() call below and saves the
3187 // old sigaction on it own.
3188 } else {
3189 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3190 "%#lx for signal %d.", (long)oldhand, sig));
3191 }
3192 }
3194 struct sigaction sigAct;
3195 sigfillset(&(sigAct.sa_mask));
3196 sigAct.sa_handler = SIG_DFL;
3197 if (!set_installed) {
3198 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3199 } else {
3200 sigAct.sa_sigaction = signalHandler;
3201 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3202 }
3203 #if __APPLE__
3204 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3205 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3206 // if the signal handler declares it will handle it on alternate stack.
3207 // Notice we only declare we will handle it on alt stack, but we are not
3208 // actually going to use real alt stack - this is just a workaround.
3209 // Please see ux_exception.c, method catch_mach_exception_raise for details
3210 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3211 if (sig == SIGSEGV) {
3212 sigAct.sa_flags |= SA_ONSTACK;
3213 }
3214 #endif
3216 // Save flags, which are set by ours
3217 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3218 sigflags[sig] = sigAct.sa_flags;
3220 int ret = sigaction(sig, &sigAct, &oldAct);
3221 assert(ret == 0, "check");
3223 void* oldhand2 = oldAct.sa_sigaction
3224 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3225 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3226 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3227 }
3229 // install signal handlers for signals that HotSpot needs to
3230 // handle in order to support Java-level exception handling.
3232 void os::Bsd::install_signal_handlers() {
3233 if (!signal_handlers_are_installed) {
3234 signal_handlers_are_installed = true;
3236 // signal-chaining
3237 typedef void (*signal_setting_t)();
3238 signal_setting_t begin_signal_setting = NULL;
3239 signal_setting_t end_signal_setting = NULL;
3240 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3241 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3242 if (begin_signal_setting != NULL) {
3243 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3244 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3245 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3246 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3247 libjsig_is_loaded = true;
3248 assert(UseSignalChaining, "should enable signal-chaining");
3249 }
3250 if (libjsig_is_loaded) {
3251 // Tell libjsig jvm is setting signal handlers
3252 (*begin_signal_setting)();
3253 }
3255 set_signal_handler(SIGSEGV, true);
3256 set_signal_handler(SIGPIPE, true);
3257 set_signal_handler(SIGBUS, true);
3258 set_signal_handler(SIGILL, true);
3259 set_signal_handler(SIGFPE, true);
3260 set_signal_handler(SIGXFSZ, true);
3262 #if defined(__APPLE__)
3263 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3264 // signals caught and handled by the JVM. To work around this, we reset the mach task
3265 // signal handler that's placed on our process by CrashReporter. This disables
3266 // CrashReporter-based reporting.
3267 //
3268 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3269 // on caught fatal signals.
3270 //
3271 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3272 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3273 // exception handling, while leaving the standard BSD signal handlers functional.
3274 kern_return_t kr;
3275 kr = task_set_exception_ports(mach_task_self(),
3276 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3277 MACH_PORT_NULL,
3278 EXCEPTION_STATE_IDENTITY,
3279 MACHINE_THREAD_STATE);
3281 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3282 #endif
3284 if (libjsig_is_loaded) {
3285 // Tell libjsig jvm finishes setting signal handlers
3286 (*end_signal_setting)();
3287 }
3289 // We don't activate signal checker if libjsig is in place, we trust ourselves
3290 // and if UserSignalHandler is installed all bets are off
3291 if (CheckJNICalls) {
3292 if (libjsig_is_loaded) {
3293 if (PrintJNIResolving) {
3294 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3295 }
3296 check_signals = false;
3297 }
3298 if (AllowUserSignalHandlers) {
3299 if (PrintJNIResolving) {
3300 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3301 }
3302 check_signals = false;
3303 }
3304 }
3305 }
3306 }
3309 /////
3310 // glibc on Bsd platform uses non-documented flag
3311 // to indicate, that some special sort of signal
3312 // trampoline is used.
3313 // We will never set this flag, and we should
3314 // ignore this flag in our diagnostic
3315 #ifdef SIGNIFICANT_SIGNAL_MASK
3316 #undef SIGNIFICANT_SIGNAL_MASK
3317 #endif
3318 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3320 static const char* get_signal_handler_name(address handler,
3321 char* buf, int buflen) {
3322 int offset;
3323 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3324 if (found) {
3325 // skip directory names
3326 const char *p1, *p2;
3327 p1 = buf;
3328 size_t len = strlen(os::file_separator());
3329 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3330 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3331 } else {
3332 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3333 }
3334 return buf;
3335 }
3337 static void print_signal_handler(outputStream* st, int sig,
3338 char* buf, size_t buflen) {
3339 struct sigaction sa;
3341 sigaction(sig, NULL, &sa);
3343 // See comment for SIGNIFICANT_SIGNAL_MASK define
3344 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3346 st->print("%s: ", os::exception_name(sig, buf, buflen));
3348 address handler = (sa.sa_flags & SA_SIGINFO)
3349 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3350 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3352 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3353 st->print("SIG_DFL");
3354 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3355 st->print("SIG_IGN");
3356 } else {
3357 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3358 }
3360 st->print(", sa_mask[0]=");
3361 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3363 address rh = VMError::get_resetted_sighandler(sig);
3364 // May be, handler was resetted by VMError?
3365 if(rh != NULL) {
3366 handler = rh;
3367 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3368 }
3370 st->print(", sa_flags=");
3371 os::Posix::print_sa_flags(st, sa.sa_flags);
3373 // Check: is it our handler?
3374 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3375 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3376 // It is our signal handler
3377 // check for flags, reset system-used one!
3378 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3379 st->print(
3380 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3381 os::Bsd::get_our_sigflags(sig));
3382 }
3383 }
3384 st->cr();
3385 }
3388 #define DO_SIGNAL_CHECK(sig) \
3389 if (!sigismember(&check_signal_done, sig)) \
3390 os::Bsd::check_signal_handler(sig)
3392 // This method is a periodic task to check for misbehaving JNI applications
3393 // under CheckJNI, we can add any periodic checks here
3395 void os::run_periodic_checks() {
3397 if (check_signals == false) return;
3399 // SEGV and BUS if overridden could potentially prevent
3400 // generation of hs*.log in the event of a crash, debugging
3401 // such a case can be very challenging, so we absolutely
3402 // check the following for a good measure:
3403 DO_SIGNAL_CHECK(SIGSEGV);
3404 DO_SIGNAL_CHECK(SIGILL);
3405 DO_SIGNAL_CHECK(SIGFPE);
3406 DO_SIGNAL_CHECK(SIGBUS);
3407 DO_SIGNAL_CHECK(SIGPIPE);
3408 DO_SIGNAL_CHECK(SIGXFSZ);
3411 // ReduceSignalUsage allows the user to override these handlers
3412 // see comments at the very top and jvm_solaris.h
3413 if (!ReduceSignalUsage) {
3414 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3415 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3416 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3417 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3418 }
3420 DO_SIGNAL_CHECK(SR_signum);
3421 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3422 }
3424 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3426 static os_sigaction_t os_sigaction = NULL;
3428 void os::Bsd::check_signal_handler(int sig) {
3429 char buf[O_BUFLEN];
3430 address jvmHandler = NULL;
3433 struct sigaction act;
3434 if (os_sigaction == NULL) {
3435 // only trust the default sigaction, in case it has been interposed
3436 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3437 if (os_sigaction == NULL) return;
3438 }
3440 os_sigaction(sig, (struct sigaction*)NULL, &act);
3443 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3445 address thisHandler = (act.sa_flags & SA_SIGINFO)
3446 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3447 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3450 switch(sig) {
3451 case SIGSEGV:
3452 case SIGBUS:
3453 case SIGFPE:
3454 case SIGPIPE:
3455 case SIGILL:
3456 case SIGXFSZ:
3457 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3458 break;
3460 case SHUTDOWN1_SIGNAL:
3461 case SHUTDOWN2_SIGNAL:
3462 case SHUTDOWN3_SIGNAL:
3463 case BREAK_SIGNAL:
3464 jvmHandler = (address)user_handler();
3465 break;
3467 case INTERRUPT_SIGNAL:
3468 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3469 break;
3471 default:
3472 if (sig == SR_signum) {
3473 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3474 } else {
3475 return;
3476 }
3477 break;
3478 }
3480 if (thisHandler != jvmHandler) {
3481 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3482 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3483 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3484 // No need to check this sig any longer
3485 sigaddset(&check_signal_done, sig);
3486 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3487 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3488 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3489 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3490 // No need to check this sig any longer
3491 sigaddset(&check_signal_done, sig);
3492 }
3494 // Dump all the signal
3495 if (sigismember(&check_signal_done, sig)) {
3496 print_signal_handlers(tty, buf, O_BUFLEN);
3497 }
3498 }
3500 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3502 extern bool signal_name(int signo, char* buf, size_t len);
3504 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3505 if (0 < exception_code && exception_code <= SIGRTMAX) {
3506 // signal
3507 if (!signal_name(exception_code, buf, size)) {
3508 jio_snprintf(buf, size, "SIG%d", exception_code);
3509 }
3510 return buf;
3511 } else {
3512 return NULL;
3513 }
3514 }
3516 // this is called _before_ the most of global arguments have been parsed
3517 void os::init(void) {
3518 char dummy; /* used to get a guess on initial stack address */
3519 // first_hrtime = gethrtime();
3521 // With BsdThreads the JavaMain thread pid (primordial thread)
3522 // is different than the pid of the java launcher thread.
3523 // So, on Bsd, the launcher thread pid is passed to the VM
3524 // via the sun.java.launcher.pid property.
3525 // Use this property instead of getpid() if it was correctly passed.
3526 // See bug 6351349.
3527 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3529 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3531 clock_tics_per_sec = CLK_TCK;
3533 init_random(1234567);
3535 ThreadCritical::initialize();
3537 Bsd::set_page_size(getpagesize());
3538 if (Bsd::page_size() == -1) {
3539 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3540 strerror(errno)));
3541 }
3542 init_page_sizes((size_t) Bsd::page_size());
3544 Bsd::initialize_system_info();
3546 // main_thread points to the aboriginal thread
3547 Bsd::_main_thread = pthread_self();
3549 Bsd::clock_init();
3550 initial_time_count = javaTimeNanos();
3552 #ifdef __APPLE__
3553 // XXXDARWIN
3554 // Work around the unaligned VM callbacks in hotspot's
3555 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3556 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3557 // alignment when doing symbol lookup. To work around this, we force early
3558 // binding of all symbols now, thus binding when alignment is known-good.
3559 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3560 #endif
3561 }
3563 // To install functions for atexit system call
3564 extern "C" {
3565 static void perfMemory_exit_helper() {
3566 perfMemory_exit();
3567 }
3568 }
3570 // this is called _after_ the global arguments have been parsed
3571 jint os::init_2(void)
3572 {
3573 // Allocate a single page and mark it as readable for safepoint polling
3574 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3575 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3577 os::set_polling_page( polling_page );
3579 #ifndef PRODUCT
3580 if(Verbose && PrintMiscellaneous)
3581 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3582 #endif
3584 if (!UseMembar) {
3585 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3586 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3587 os::set_memory_serialize_page( mem_serialize_page );
3589 #ifndef PRODUCT
3590 if(Verbose && PrintMiscellaneous)
3591 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3592 #endif
3593 }
3595 // initialize suspend/resume support - must do this before signal_sets_init()
3596 if (SR_initialize() != 0) {
3597 perror("SR_initialize failed");
3598 return JNI_ERR;
3599 }
3601 Bsd::signal_sets_init();
3602 Bsd::install_signal_handlers();
3604 // Check minimum allowable stack size for thread creation and to initialize
3605 // the java system classes, including StackOverflowError - depends on page
3606 // size. Add a page for compiler2 recursion in main thread.
3607 // Add in 2*BytesPerWord times page size to account for VM stack during
3608 // class initialization depending on 32 or 64 bit VM.
3609 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3610 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3611 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3613 size_t threadStackSizeInBytes = ThreadStackSize * K;
3614 if (threadStackSizeInBytes != 0 &&
3615 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3616 tty->print_cr("\nThe stack size specified is too small, "
3617 "Specify at least %dk",
3618 os::Bsd::min_stack_allowed/ K);
3619 return JNI_ERR;
3620 }
3622 // Make the stack size a multiple of the page size so that
3623 // the yellow/red zones can be guarded.
3624 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3625 vm_page_size()));
3627 if (MaxFDLimit) {
3628 // set the number of file descriptors to max. print out error
3629 // if getrlimit/setrlimit fails but continue regardless.
3630 struct rlimit nbr_files;
3631 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3632 if (status != 0) {
3633 if (PrintMiscellaneous && (Verbose || WizardMode))
3634 perror("os::init_2 getrlimit failed");
3635 } else {
3636 nbr_files.rlim_cur = nbr_files.rlim_max;
3638 #ifdef __APPLE__
3639 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3640 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3641 // be used instead
3642 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3643 #endif
3645 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3646 if (status != 0) {
3647 if (PrintMiscellaneous && (Verbose || WizardMode))
3648 perror("os::init_2 setrlimit failed");
3649 }
3650 }
3651 }
3653 // at-exit methods are called in the reverse order of their registration.
3654 // atexit functions are called on return from main or as a result of a
3655 // call to exit(3C). There can be only 32 of these functions registered
3656 // and atexit() does not set errno.
3658 if (PerfAllowAtExitRegistration) {
3659 // only register atexit functions if PerfAllowAtExitRegistration is set.
3660 // atexit functions can be delayed until process exit time, which
3661 // can be problematic for embedded VM situations. Embedded VMs should
3662 // call DestroyJavaVM() to assure that VM resources are released.
3664 // note: perfMemory_exit_helper atexit function may be removed in
3665 // the future if the appropriate cleanup code can be added to the
3666 // VM_Exit VMOperation's doit method.
3667 if (atexit(perfMemory_exit_helper) != 0) {
3668 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3669 }
3670 }
3672 // initialize thread priority policy
3673 prio_init();
3675 #ifdef __APPLE__
3676 // dynamically link to objective c gc registration
3677 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3678 if (handleLibObjc != NULL) {
3679 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3680 }
3681 #endif
3683 return JNI_OK;
3684 }
3686 // this is called at the end of vm_initialization
3687 void os::init_3(void) { }
3689 // Mark the polling page as unreadable
3690 void os::make_polling_page_unreadable(void) {
3691 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3692 fatal("Could not disable polling page");
3693 };
3695 // Mark the polling page as readable
3696 void os::make_polling_page_readable(void) {
3697 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3698 fatal("Could not enable polling page");
3699 }
3700 };
3702 int os::active_processor_count() {
3703 return _processor_count;
3704 }
3706 void os::set_native_thread_name(const char *name) {
3707 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3708 // This is only supported in Snow Leopard and beyond
3709 if (name != NULL) {
3710 // Add a "Java: " prefix to the name
3711 char buf[MAXTHREADNAMESIZE];
3712 snprintf(buf, sizeof(buf), "Java: %s", name);
3713 pthread_setname_np(buf);
3714 }
3715 #endif
3716 }
3718 bool os::distribute_processes(uint length, uint* distribution) {
3719 // Not yet implemented.
3720 return false;
3721 }
3723 bool os::bind_to_processor(uint processor_id) {
3724 // Not yet implemented.
3725 return false;
3726 }
3728 void os::SuspendedThreadTask::internal_do_task() {
3729 if (do_suspend(_thread->osthread())) {
3730 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3731 do_task(context);
3732 do_resume(_thread->osthread());
3733 }
3734 }
3736 ///
3737 class PcFetcher : public os::SuspendedThreadTask {
3738 public:
3739 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3740 ExtendedPC result();
3741 protected:
3742 void do_task(const os::SuspendedThreadTaskContext& context);
3743 private:
3744 ExtendedPC _epc;
3745 };
3747 ExtendedPC PcFetcher::result() {
3748 guarantee(is_done(), "task is not done yet.");
3749 return _epc;
3750 }
3752 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3753 Thread* thread = context.thread();
3754 OSThread* osthread = thread->osthread();
3755 if (osthread->ucontext() != NULL) {
3756 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3757 } else {
3758 // NULL context is unexpected, double-check this is the VMThread
3759 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3760 }
3761 }
3763 // Suspends the target using the signal mechanism and then grabs the PC before
3764 // resuming the target. Used by the flat-profiler only
3765 ExtendedPC os::get_thread_pc(Thread* thread) {
3766 // Make sure that it is called by the watcher for the VMThread
3767 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3768 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3770 PcFetcher fetcher(thread);
3771 fetcher.run();
3772 return fetcher.result();
3773 }
3775 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3776 {
3777 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3778 }
3780 ////////////////////////////////////////////////////////////////////////////////
3781 // debug support
3783 bool os::find(address addr, outputStream* st) {
3784 Dl_info dlinfo;
3785 memset(&dlinfo, 0, sizeof(dlinfo));
3786 if (dladdr(addr, &dlinfo) != 0) {
3787 st->print(PTR_FORMAT ": ", addr);
3788 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3789 st->print("%s+%#x", dlinfo.dli_sname,
3790 addr - (intptr_t)dlinfo.dli_saddr);
3791 } else if (dlinfo.dli_fbase != NULL) {
3792 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3793 } else {
3794 st->print("<absolute address>");
3795 }
3796 if (dlinfo.dli_fname != NULL) {
3797 st->print(" in %s", dlinfo.dli_fname);
3798 }
3799 if (dlinfo.dli_fbase != NULL) {
3800 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3801 }
3802 st->cr();
3804 if (Verbose) {
3805 // decode some bytes around the PC
3806 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3807 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3808 address lowest = (address) dlinfo.dli_sname;
3809 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3810 if (begin < lowest) begin = lowest;
3811 Dl_info dlinfo2;
3812 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3813 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3814 end = (address) dlinfo2.dli_saddr;
3815 Disassembler::decode(begin, end, st);
3816 }
3817 return true;
3818 }
3819 return false;
3820 }
3822 ////////////////////////////////////////////////////////////////////////////////
3823 // misc
3825 // This does not do anything on Bsd. This is basically a hook for being
3826 // able to use structured exception handling (thread-local exception filters)
3827 // on, e.g., Win32.
3828 void
3829 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3830 JavaCallArguments* args, Thread* thread) {
3831 f(value, method, args, thread);
3832 }
3834 void os::print_statistics() {
3835 }
3837 int os::message_box(const char* title, const char* message) {
3838 int i;
3839 fdStream err(defaultStream::error_fd());
3840 for (i = 0; i < 78; i++) err.print_raw("=");
3841 err.cr();
3842 err.print_raw_cr(title);
3843 for (i = 0; i < 78; i++) err.print_raw("-");
3844 err.cr();
3845 err.print_raw_cr(message);
3846 for (i = 0; i < 78; i++) err.print_raw("=");
3847 err.cr();
3849 char buf[16];
3850 // Prevent process from exiting upon "read error" without consuming all CPU
3851 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3853 return buf[0] == 'y' || buf[0] == 'Y';
3854 }
3856 int os::stat(const char *path, struct stat *sbuf) {
3857 char pathbuf[MAX_PATH];
3858 if (strlen(path) > MAX_PATH - 1) {
3859 errno = ENAMETOOLONG;
3860 return -1;
3861 }
3862 os::native_path(strcpy(pathbuf, path));
3863 return ::stat(pathbuf, sbuf);
3864 }
3866 bool os::check_heap(bool force) {
3867 return true;
3868 }
3870 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3871 return ::vsnprintf(buf, count, format, args);
3872 }
3874 // Is a (classpath) directory empty?
3875 bool os::dir_is_empty(const char* path) {
3876 DIR *dir = NULL;
3877 struct dirent *ptr;
3879 dir = opendir(path);
3880 if (dir == NULL) return true;
3882 /* Scan the directory */
3883 bool result = true;
3884 char buf[sizeof(struct dirent) + MAX_PATH];
3885 while (result && (ptr = ::readdir(dir)) != NULL) {
3886 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3887 result = false;
3888 }
3889 }
3890 closedir(dir);
3891 return result;
3892 }
3894 // This code originates from JDK's sysOpen and open64_w
3895 // from src/solaris/hpi/src/system_md.c
3897 #ifndef O_DELETE
3898 #define O_DELETE 0x10000
3899 #endif
3901 // Open a file. Unlink the file immediately after open returns
3902 // if the specified oflag has the O_DELETE flag set.
3903 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3905 int os::open(const char *path, int oflag, int mode) {
3907 if (strlen(path) > MAX_PATH - 1) {
3908 errno = ENAMETOOLONG;
3909 return -1;
3910 }
3911 int fd;
3912 int o_delete = (oflag & O_DELETE);
3913 oflag = oflag & ~O_DELETE;
3915 fd = ::open(path, oflag, mode);
3916 if (fd == -1) return -1;
3918 //If the open succeeded, the file might still be a directory
3919 {
3920 struct stat buf;
3921 int ret = ::fstat(fd, &buf);
3922 int st_mode = buf.st_mode;
3924 if (ret != -1) {
3925 if ((st_mode & S_IFMT) == S_IFDIR) {
3926 errno = EISDIR;
3927 ::close(fd);
3928 return -1;
3929 }
3930 } else {
3931 ::close(fd);
3932 return -1;
3933 }
3934 }
3936 /*
3937 * All file descriptors that are opened in the JVM and not
3938 * specifically destined for a subprocess should have the
3939 * close-on-exec flag set. If we don't set it, then careless 3rd
3940 * party native code might fork and exec without closing all
3941 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3942 * UNIXProcess.c), and this in turn might:
3943 *
3944 * - cause end-of-file to fail to be detected on some file
3945 * descriptors, resulting in mysterious hangs, or
3946 *
3947 * - might cause an fopen in the subprocess to fail on a system
3948 * suffering from bug 1085341.
3949 *
3950 * (Yes, the default setting of the close-on-exec flag is a Unix
3951 * design flaw)
3952 *
3953 * See:
3954 * 1085341: 32-bit stdio routines should support file descriptors >255
3955 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3956 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3957 */
3958 #ifdef FD_CLOEXEC
3959 {
3960 int flags = ::fcntl(fd, F_GETFD);
3961 if (flags != -1)
3962 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3963 }
3964 #endif
3966 if (o_delete != 0) {
3967 ::unlink(path);
3968 }
3969 return fd;
3970 }
3973 // create binary file, rewriting existing file if required
3974 int os::create_binary_file(const char* path, bool rewrite_existing) {
3975 int oflags = O_WRONLY | O_CREAT;
3976 if (!rewrite_existing) {
3977 oflags |= O_EXCL;
3978 }
3979 return ::open(path, oflags, S_IREAD | S_IWRITE);
3980 }
3982 // return current position of file pointer
3983 jlong os::current_file_offset(int fd) {
3984 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3985 }
3987 // move file pointer to the specified offset
3988 jlong os::seek_to_file_offset(int fd, jlong offset) {
3989 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3990 }
3992 // This code originates from JDK's sysAvailable
3993 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3995 int os::available(int fd, jlong *bytes) {
3996 jlong cur, end;
3997 int mode;
3998 struct stat buf;
4000 if (::fstat(fd, &buf) >= 0) {
4001 mode = buf.st_mode;
4002 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4003 /*
4004 * XXX: is the following call interruptible? If so, this might
4005 * need to go through the INTERRUPT_IO() wrapper as for other
4006 * blocking, interruptible calls in this file.
4007 */
4008 int n;
4009 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4010 *bytes = n;
4011 return 1;
4012 }
4013 }
4014 }
4015 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4016 return 0;
4017 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4018 return 0;
4019 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4020 return 0;
4021 }
4022 *bytes = end - cur;
4023 return 1;
4024 }
4026 int os::socket_available(int fd, jint *pbytes) {
4027 if (fd < 0)
4028 return OS_OK;
4030 int ret;
4032 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4034 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4035 // is expected to return 0 on failure and 1 on success to the jdk.
4037 return (ret == OS_ERR) ? 0 : 1;
4038 }
4040 // Map a block of memory.
4041 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4042 char *addr, size_t bytes, bool read_only,
4043 bool allow_exec) {
4044 int prot;
4045 int flags;
4047 if (read_only) {
4048 prot = PROT_READ;
4049 flags = MAP_SHARED;
4050 } else {
4051 prot = PROT_READ | PROT_WRITE;
4052 flags = MAP_PRIVATE;
4053 }
4055 if (allow_exec) {
4056 prot |= PROT_EXEC;
4057 }
4059 if (addr != NULL) {
4060 flags |= MAP_FIXED;
4061 }
4063 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4064 fd, file_offset);
4065 if (mapped_address == MAP_FAILED) {
4066 return NULL;
4067 }
4068 return mapped_address;
4069 }
4072 // Remap a block of memory.
4073 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4074 char *addr, size_t bytes, bool read_only,
4075 bool allow_exec) {
4076 // same as map_memory() on this OS
4077 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4078 allow_exec);
4079 }
4082 // Unmap a block of memory.
4083 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4084 return munmap(addr, bytes) == 0;
4085 }
4087 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4088 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4089 // of a thread.
4090 //
4091 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4092 // the fast estimate available on the platform.
4094 jlong os::current_thread_cpu_time() {
4095 #ifdef __APPLE__
4096 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4097 #else
4098 Unimplemented();
4099 return 0;
4100 #endif
4101 }
4103 jlong os::thread_cpu_time(Thread* thread) {
4104 #ifdef __APPLE__
4105 return os::thread_cpu_time(thread, true /* user + sys */);
4106 #else
4107 Unimplemented();
4108 return 0;
4109 #endif
4110 }
4112 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4113 #ifdef __APPLE__
4114 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4115 #else
4116 Unimplemented();
4117 return 0;
4118 #endif
4119 }
4121 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4122 #ifdef __APPLE__
4123 struct thread_basic_info tinfo;
4124 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4125 kern_return_t kr;
4126 thread_t mach_thread;
4128 mach_thread = thread->osthread()->thread_id();
4129 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4130 if (kr != KERN_SUCCESS)
4131 return -1;
4133 if (user_sys_cpu_time) {
4134 jlong nanos;
4135 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4136 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4137 return nanos;
4138 } else {
4139 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4140 }
4141 #else
4142 Unimplemented();
4143 return 0;
4144 #endif
4145 }
4148 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4149 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4150 info_ptr->may_skip_backward = false; // elapsed time not wall time
4151 info_ptr->may_skip_forward = false; // elapsed time not wall time
4152 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4153 }
4155 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4156 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4157 info_ptr->may_skip_backward = false; // elapsed time not wall time
4158 info_ptr->may_skip_forward = false; // elapsed time not wall time
4159 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4160 }
4162 bool os::is_thread_cpu_time_supported() {
4163 #ifdef __APPLE__
4164 return true;
4165 #else
4166 return false;
4167 #endif
4168 }
4170 // System loadavg support. Returns -1 if load average cannot be obtained.
4171 // Bsd doesn't yet have a (official) notion of processor sets,
4172 // so just return the system wide load average.
4173 int os::loadavg(double loadavg[], int nelem) {
4174 return ::getloadavg(loadavg, nelem);
4175 }
4177 void os::pause() {
4178 char filename[MAX_PATH];
4179 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4180 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4181 } else {
4182 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4183 }
4185 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4186 if (fd != -1) {
4187 struct stat buf;
4188 ::close(fd);
4189 while (::stat(filename, &buf) == 0) {
4190 (void)::poll(NULL, 0, 100);
4191 }
4192 } else {
4193 jio_fprintf(stderr,
4194 "Could not open pause file '%s', continuing immediately.\n", filename);
4195 }
4196 }
4199 // Refer to the comments in os_solaris.cpp park-unpark.
4200 //
4201 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4202 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4203 // For specifics regarding the bug see GLIBC BUGID 261237 :
4204 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4205 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4206 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4207 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4208 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4209 // and monitorenter when we're using 1-0 locking. All those operations may result in
4210 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4211 // of libpthread avoids the problem, but isn't practical.
4212 //
4213 // Possible remedies:
4214 //
4215 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4216 // This is palliative and probabilistic, however. If the thread is preempted
4217 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4218 // than the minimum period may have passed, and the abstime may be stale (in the
4219 // past) resultin in a hang. Using this technique reduces the odds of a hang
4220 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4221 //
4222 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4223 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4224 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4225 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4226 // thread.
4227 //
4228 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4229 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4230 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4231 // This also works well. In fact it avoids kernel-level scalability impediments
4232 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4233 // timers in a graceful fashion.
4234 //
4235 // 4. When the abstime value is in the past it appears that control returns
4236 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4237 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4238 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4239 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4240 // It may be possible to avoid reinitialization by checking the return
4241 // value from pthread_cond_timedwait(). In addition to reinitializing the
4242 // condvar we must establish the invariant that cond_signal() is only called
4243 // within critical sections protected by the adjunct mutex. This prevents
4244 // cond_signal() from "seeing" a condvar that's in the midst of being
4245 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4246 // desirable signal-after-unlock optimization that avoids futile context switching.
4247 //
4248 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4249 // structure when a condvar is used or initialized. cond_destroy() would
4250 // release the helper structure. Our reinitialize-after-timedwait fix
4251 // put excessive stress on malloc/free and locks protecting the c-heap.
4252 //
4253 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4254 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4255 // and only enabling the work-around for vulnerable environments.
4257 // utility to compute the abstime argument to timedwait:
4258 // millis is the relative timeout time
4259 // abstime will be the absolute timeout time
4260 // TODO: replace compute_abstime() with unpackTime()
4262 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4263 if (millis < 0) millis = 0;
4264 struct timeval now;
4265 int status = gettimeofday(&now, NULL);
4266 assert(status == 0, "gettimeofday");
4267 jlong seconds = millis / 1000;
4268 millis %= 1000;
4269 if (seconds > 50000000) { // see man cond_timedwait(3T)
4270 seconds = 50000000;
4271 }
4272 abstime->tv_sec = now.tv_sec + seconds;
4273 long usec = now.tv_usec + millis * 1000;
4274 if (usec >= 1000000) {
4275 abstime->tv_sec += 1;
4276 usec -= 1000000;
4277 }
4278 abstime->tv_nsec = usec * 1000;
4279 return abstime;
4280 }
4283 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4284 // Conceptually TryPark() should be equivalent to park(0).
4286 int os::PlatformEvent::TryPark() {
4287 for (;;) {
4288 const int v = _Event ;
4289 guarantee ((v == 0) || (v == 1), "invariant") ;
4290 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4291 }
4292 }
4294 void os::PlatformEvent::park() { // AKA "down()"
4295 // Invariant: Only the thread associated with the Event/PlatformEvent
4296 // may call park().
4297 // TODO: assert that _Assoc != NULL or _Assoc == Self
4298 int v ;
4299 for (;;) {
4300 v = _Event ;
4301 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4302 }
4303 guarantee (v >= 0, "invariant") ;
4304 if (v == 0) {
4305 // Do this the hard way by blocking ...
4306 int status = pthread_mutex_lock(_mutex);
4307 assert_status(status == 0, status, "mutex_lock");
4308 guarantee (_nParked == 0, "invariant") ;
4309 ++ _nParked ;
4310 while (_Event < 0) {
4311 status = pthread_cond_wait(_cond, _mutex);
4312 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4313 // Treat this the same as if the wait was interrupted
4314 if (status == ETIMEDOUT) { status = EINTR; }
4315 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4316 }
4317 -- _nParked ;
4319 _Event = 0 ;
4320 status = pthread_mutex_unlock(_mutex);
4321 assert_status(status == 0, status, "mutex_unlock");
4322 // Paranoia to ensure our locked and lock-free paths interact
4323 // correctly with each other.
4324 OrderAccess::fence();
4325 }
4326 guarantee (_Event >= 0, "invariant") ;
4327 }
4329 int os::PlatformEvent::park(jlong millis) {
4330 guarantee (_nParked == 0, "invariant") ;
4332 int v ;
4333 for (;;) {
4334 v = _Event ;
4335 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4336 }
4337 guarantee (v >= 0, "invariant") ;
4338 if (v != 0) return OS_OK ;
4340 // We do this the hard way, by blocking the thread.
4341 // Consider enforcing a minimum timeout value.
4342 struct timespec abst;
4343 compute_abstime(&abst, millis);
4345 int ret = OS_TIMEOUT;
4346 int status = pthread_mutex_lock(_mutex);
4347 assert_status(status == 0, status, "mutex_lock");
4348 guarantee (_nParked == 0, "invariant") ;
4349 ++_nParked ;
4351 // Object.wait(timo) will return because of
4352 // (a) notification
4353 // (b) timeout
4354 // (c) thread.interrupt
4355 //
4356 // Thread.interrupt and object.notify{All} both call Event::set.
4357 // That is, we treat thread.interrupt as a special case of notification.
4358 // The underlying Solaris implementation, cond_timedwait, admits
4359 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4360 // JVM from making those visible to Java code. As such, we must
4361 // filter out spurious wakeups. We assume all ETIME returns are valid.
4362 //
4363 // TODO: properly differentiate simultaneous notify+interrupt.
4364 // In that case, we should propagate the notify to another waiter.
4366 while (_Event < 0) {
4367 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4368 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4369 pthread_cond_destroy (_cond);
4370 pthread_cond_init (_cond, NULL) ;
4371 }
4372 assert_status(status == 0 || status == EINTR ||
4373 status == ETIMEDOUT,
4374 status, "cond_timedwait");
4375 if (!FilterSpuriousWakeups) break ; // previous semantics
4376 if (status == ETIMEDOUT) break ;
4377 // We consume and ignore EINTR and spurious wakeups.
4378 }
4379 --_nParked ;
4380 if (_Event >= 0) {
4381 ret = OS_OK;
4382 }
4383 _Event = 0 ;
4384 status = pthread_mutex_unlock(_mutex);
4385 assert_status(status == 0, status, "mutex_unlock");
4386 assert (_nParked == 0, "invariant") ;
4387 // Paranoia to ensure our locked and lock-free paths interact
4388 // correctly with each other.
4389 OrderAccess::fence();
4390 return ret;
4391 }
4393 void os::PlatformEvent::unpark() {
4394 // Transitions for _Event:
4395 // 0 :=> 1
4396 // 1 :=> 1
4397 // -1 :=> either 0 or 1; must signal target thread
4398 // That is, we can safely transition _Event from -1 to either
4399 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4400 // unpark() calls.
4401 // See also: "Semaphores in Plan 9" by Mullender & Cox
4402 //
4403 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4404 // that it will take two back-to-back park() calls for the owning
4405 // thread to block. This has the benefit of forcing a spurious return
4406 // from the first park() call after an unpark() call which will help
4407 // shake out uses of park() and unpark() without condition variables.
4409 if (Atomic::xchg(1, &_Event) >= 0) return;
4411 // Wait for the thread associated with the event to vacate
4412 int status = pthread_mutex_lock(_mutex);
4413 assert_status(status == 0, status, "mutex_lock");
4414 int AnyWaiters = _nParked;
4415 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4416 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4417 AnyWaiters = 0;
4418 pthread_cond_signal(_cond);
4419 }
4420 status = pthread_mutex_unlock(_mutex);
4421 assert_status(status == 0, status, "mutex_unlock");
4422 if (AnyWaiters != 0) {
4423 status = pthread_cond_signal(_cond);
4424 assert_status(status == 0, status, "cond_signal");
4425 }
4427 // Note that we signal() _after dropping the lock for "immortal" Events.
4428 // This is safe and avoids a common class of futile wakeups. In rare
4429 // circumstances this can cause a thread to return prematurely from
4430 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4431 // simply re-test the condition and re-park itself.
4432 }
4435 // JSR166
4436 // -------------------------------------------------------
4438 /*
4439 * The solaris and bsd implementations of park/unpark are fairly
4440 * conservative for now, but can be improved. They currently use a
4441 * mutex/condvar pair, plus a a count.
4442 * Park decrements count if > 0, else does a condvar wait. Unpark
4443 * sets count to 1 and signals condvar. Only one thread ever waits
4444 * on the condvar. Contention seen when trying to park implies that someone
4445 * is unparking you, so don't wait. And spurious returns are fine, so there
4446 * is no need to track notifications.
4447 */
4449 #define MAX_SECS 100000000
4450 /*
4451 * This code is common to bsd and solaris and will be moved to a
4452 * common place in dolphin.
4453 *
4454 * The passed in time value is either a relative time in nanoseconds
4455 * or an absolute time in milliseconds. Either way it has to be unpacked
4456 * into suitable seconds and nanoseconds components and stored in the
4457 * given timespec structure.
4458 * Given time is a 64-bit value and the time_t used in the timespec is only
4459 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4460 * overflow if times way in the future are given. Further on Solaris versions
4461 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4462 * number of seconds, in abstime, is less than current_time + 100,000,000.
4463 * As it will be 28 years before "now + 100000000" will overflow we can
4464 * ignore overflow and just impose a hard-limit on seconds using the value
4465 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4466 * years from "now".
4467 */
4469 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4470 assert (time > 0, "convertTime");
4472 struct timeval now;
4473 int status = gettimeofday(&now, NULL);
4474 assert(status == 0, "gettimeofday");
4476 time_t max_secs = now.tv_sec + MAX_SECS;
4478 if (isAbsolute) {
4479 jlong secs = time / 1000;
4480 if (secs > max_secs) {
4481 absTime->tv_sec = max_secs;
4482 }
4483 else {
4484 absTime->tv_sec = secs;
4485 }
4486 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4487 }
4488 else {
4489 jlong secs = time / NANOSECS_PER_SEC;
4490 if (secs >= MAX_SECS) {
4491 absTime->tv_sec = max_secs;
4492 absTime->tv_nsec = 0;
4493 }
4494 else {
4495 absTime->tv_sec = now.tv_sec + secs;
4496 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4497 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4498 absTime->tv_nsec -= NANOSECS_PER_SEC;
4499 ++absTime->tv_sec; // note: this must be <= max_secs
4500 }
4501 }
4502 }
4503 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4504 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4505 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4506 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4507 }
4509 void Parker::park(bool isAbsolute, jlong time) {
4510 // Ideally we'd do something useful while spinning, such
4511 // as calling unpackTime().
4513 // Optional fast-path check:
4514 // Return immediately if a permit is available.
4515 // We depend on Atomic::xchg() having full barrier semantics
4516 // since we are doing a lock-free update to _counter.
4517 if (Atomic::xchg(0, &_counter) > 0) return;
4519 Thread* thread = Thread::current();
4520 assert(thread->is_Java_thread(), "Must be JavaThread");
4521 JavaThread *jt = (JavaThread *)thread;
4523 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4524 // Check interrupt before trying to wait
4525 if (Thread::is_interrupted(thread, false)) {
4526 return;
4527 }
4529 // Next, demultiplex/decode time arguments
4530 struct timespec absTime;
4531 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4532 return;
4533 }
4534 if (time > 0) {
4535 unpackTime(&absTime, isAbsolute, time);
4536 }
4539 // Enter safepoint region
4540 // Beware of deadlocks such as 6317397.
4541 // The per-thread Parker:: mutex is a classic leaf-lock.
4542 // In particular a thread must never block on the Threads_lock while
4543 // holding the Parker:: mutex. If safepoints are pending both the
4544 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4545 ThreadBlockInVM tbivm(jt);
4547 // Don't wait if cannot get lock since interference arises from
4548 // unblocking. Also. check interrupt before trying wait
4549 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4550 return;
4551 }
4553 int status ;
4554 if (_counter > 0) { // no wait needed
4555 _counter = 0;
4556 status = pthread_mutex_unlock(_mutex);
4557 assert (status == 0, "invariant") ;
4558 // Paranoia to ensure our locked and lock-free paths interact
4559 // correctly with each other and Java-level accesses.
4560 OrderAccess::fence();
4561 return;
4562 }
4564 #ifdef ASSERT
4565 // Don't catch signals while blocked; let the running threads have the signals.
4566 // (This allows a debugger to break into the running thread.)
4567 sigset_t oldsigs;
4568 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4569 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4570 #endif
4572 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4573 jt->set_suspend_equivalent();
4574 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4576 if (time == 0) {
4577 status = pthread_cond_wait (_cond, _mutex) ;
4578 } else {
4579 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4580 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4581 pthread_cond_destroy (_cond) ;
4582 pthread_cond_init (_cond, NULL);
4583 }
4584 }
4585 assert_status(status == 0 || status == EINTR ||
4586 status == ETIMEDOUT,
4587 status, "cond_timedwait");
4589 #ifdef ASSERT
4590 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4591 #endif
4593 _counter = 0 ;
4594 status = pthread_mutex_unlock(_mutex) ;
4595 assert_status(status == 0, status, "invariant") ;
4596 // Paranoia to ensure our locked and lock-free paths interact
4597 // correctly with each other and Java-level accesses.
4598 OrderAccess::fence();
4600 // If externally suspended while waiting, re-suspend
4601 if (jt->handle_special_suspend_equivalent_condition()) {
4602 jt->java_suspend_self();
4603 }
4604 }
4606 void Parker::unpark() {
4607 int s, status ;
4608 status = pthread_mutex_lock(_mutex);
4609 assert (status == 0, "invariant") ;
4610 s = _counter;
4611 _counter = 1;
4612 if (s < 1) {
4613 if (WorkAroundNPTLTimedWaitHang) {
4614 status = pthread_cond_signal (_cond) ;
4615 assert (status == 0, "invariant") ;
4616 status = pthread_mutex_unlock(_mutex);
4617 assert (status == 0, "invariant") ;
4618 } else {
4619 status = pthread_mutex_unlock(_mutex);
4620 assert (status == 0, "invariant") ;
4621 status = pthread_cond_signal (_cond) ;
4622 assert (status == 0, "invariant") ;
4623 }
4624 } else {
4625 pthread_mutex_unlock(_mutex);
4626 assert (status == 0, "invariant") ;
4627 }
4628 }
4631 /* Darwin has no "environ" in a dynamic library. */
4632 #ifdef __APPLE__
4633 #include <crt_externs.h>
4634 #define environ (*_NSGetEnviron())
4635 #else
4636 extern char** environ;
4637 #endif
4639 // Run the specified command in a separate process. Return its exit value,
4640 // or -1 on failure (e.g. can't fork a new process).
4641 // Unlike system(), this function can be called from signal handler. It
4642 // doesn't block SIGINT et al.
4643 int os::fork_and_exec(char* cmd) {
4644 const char * argv[4] = {"sh", "-c", cmd, NULL};
4646 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4647 // pthread_atfork handlers and reset pthread library. All we need is a
4648 // separate process to execve. Make a direct syscall to fork process.
4649 // On IA64 there's no fork syscall, we have to use fork() and hope for
4650 // the best...
4651 pid_t pid = fork();
4653 if (pid < 0) {
4654 // fork failed
4655 return -1;
4657 } else if (pid == 0) {
4658 // child process
4660 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4661 // first to kill every thread on the thread list. Because this list is
4662 // not reset by fork() (see notes above), execve() will instead kill
4663 // every thread in the parent process. We know this is the only thread
4664 // in the new process, so make a system call directly.
4665 // IA64 should use normal execve() from glibc to match the glibc fork()
4666 // above.
4667 execve("/bin/sh", (char* const*)argv, environ);
4669 // execve failed
4670 _exit(-1);
4672 } else {
4673 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4674 // care about the actual exit code, for now.
4676 int status;
4678 // Wait for the child process to exit. This returns immediately if
4679 // the child has already exited. */
4680 while (waitpid(pid, &status, 0) < 0) {
4681 switch (errno) {
4682 case ECHILD: return 0;
4683 case EINTR: break;
4684 default: return -1;
4685 }
4686 }
4688 if (WIFEXITED(status)) {
4689 // The child exited normally; get its exit code.
4690 return WEXITSTATUS(status);
4691 } else if (WIFSIGNALED(status)) {
4692 // The child exited because of a signal
4693 // The best value to return is 0x80 + signal number,
4694 // because that is what all Unix shells do, and because
4695 // it allows callers to distinguish between process exit and
4696 // process death by signal.
4697 return 0x80 + WTERMSIG(status);
4698 } else {
4699 // Unknown exit code; pass it through
4700 return status;
4701 }
4702 }
4703 }
4705 // is_headless_jre()
4706 //
4707 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4708 // in order to report if we are running in a headless jre
4709 //
4710 // Since JDK8 xawt/libmawt.so was moved into the same directory
4711 // as libawt.so, and renamed libawt_xawt.so
4712 //
4713 bool os::is_headless_jre() {
4714 #ifdef __APPLE__
4715 // We no longer build headless-only on Mac OS X
4716 return false;
4717 #else
4718 struct stat statbuf;
4719 char buf[MAXPATHLEN];
4720 char libmawtpath[MAXPATHLEN];
4721 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4722 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4723 char *p;
4725 // Get path to libjvm.so
4726 os::jvm_path(buf, sizeof(buf));
4728 // Get rid of libjvm.so
4729 p = strrchr(buf, '/');
4730 if (p == NULL) return false;
4731 else *p = '\0';
4733 // Get rid of client or server
4734 p = strrchr(buf, '/');
4735 if (p == NULL) return false;
4736 else *p = '\0';
4738 // check xawt/libmawt.so
4739 strcpy(libmawtpath, buf);
4740 strcat(libmawtpath, xawtstr);
4741 if (::stat(libmawtpath, &statbuf) == 0) return false;
4743 // check libawt_xawt.so
4744 strcpy(libmawtpath, buf);
4745 strcat(libmawtpath, new_xawtstr);
4746 if (::stat(libmawtpath, &statbuf) == 0) return false;
4748 return true;
4749 #endif
4750 }
4752 // Get the default path to the core file
4753 // Returns the length of the string
4754 int os::get_core_path(char* buffer, size_t bufferSize) {
4755 int n = jio_snprintf(buffer, bufferSize, "/cores");
4757 // Truncate if theoretical string was longer than bufferSize
4758 n = MIN2(n, (int)bufferSize);
4760 return n;
4761 }
4763 #ifndef PRODUCT
4764 void TestReserveMemorySpecial_test() {
4765 // No tests available for this platform
4766 }
4767 #endif