Sat, 12 Oct 2013 13:09:18 -0400
8025942: os::Bsd::available_memory() needs implementation
Summary: Implement using the host_statistics64() api.
Reviewed-by: dsamersoff, morris, dholmes, coleenp, hseigel, dcubed
Contributed-by: gerard.ziemski@oracle.com
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 // no precompiled headers
26 #include "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
103 # include <sys/syscall.h>
105 #if defined(__FreeBSD__) || defined(__NetBSD__)
106 # include <elf.h>
107 #endif
109 #ifdef __APPLE__
110 # include <mach/mach.h> // semaphore_* API
111 # include <mach-o/dyld.h>
112 # include <sys/proc_info.h>
113 # include <objc/objc-auto.h>
114 #endif
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
118 #endif
120 #define MAX_PATH (2 * K)
122 // for timer info max values which include all bits
123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
125 #define LARGEPAGES_BIT (1 << 6)
126 ////////////////////////////////////////////////////////////////////////////////
127 // global variables
128 julong os::Bsd::_physical_memory = 0;
131 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
132 pthread_t os::Bsd::_main_thread;
133 int os::Bsd::_page_size = -1;
135 static jlong initial_time_count=0;
137 static int clock_tics_per_sec = 100;
139 // For diagnostics to print a message once. see run_periodic_checks
140 static sigset_t check_signal_done;
141 static bool check_signals = true;
143 static pid_t _initial_pid = 0;
145 /* Signal number used to suspend/resume a thread */
147 /* do not use any signal number less than SIGSEGV, see 4355769 */
148 static int SR_signum = SIGUSR2;
149 sigset_t SR_sigset;
152 ////////////////////////////////////////////////////////////////////////////////
153 // utility functions
155 static int SR_initialize();
156 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
158 julong os::available_memory() {
159 return Bsd::available_memory();
160 }
162 // available here means free
163 julong os::Bsd::available_memory() {
164 uint64_t available = physical_memory() >> 2;
165 #ifdef __APPLE__
166 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
167 vm_statistics64_data_t vmstat;
168 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
169 (host_info64_t)&vmstat, &count);
170 assert(kerr == KERN_SUCCESS,
171 "host_statistics64 failed - check mach_host_self() and count");
172 if (kerr == KERN_SUCCESS) {
173 available = vmstat.free_count * os::vm_page_size();
174 }
175 #endif
176 return available;
177 }
179 julong os::physical_memory() {
180 return Bsd::physical_memory();
181 }
183 ////////////////////////////////////////////////////////////////////////////////
184 // environment support
186 bool os::getenv(const char* name, char* buf, int len) {
187 const char* val = ::getenv(name);
188 if (val != NULL && strlen(val) < (size_t)len) {
189 strcpy(buf, val);
190 return true;
191 }
192 if (len > 0) buf[0] = 0; // return a null string
193 return false;
194 }
197 // Return true if user is running as root.
199 bool os::have_special_privileges() {
200 static bool init = false;
201 static bool privileges = false;
202 if (!init) {
203 privileges = (getuid() != geteuid()) || (getgid() != getegid());
204 init = true;
205 }
206 return privileges;
207 }
211 // Cpu architecture string
212 #if defined(ZERO)
213 static char cpu_arch[] = ZERO_LIBARCH;
214 #elif defined(IA64)
215 static char cpu_arch[] = "ia64";
216 #elif defined(IA32)
217 static char cpu_arch[] = "i386";
218 #elif defined(AMD64)
219 static char cpu_arch[] = "amd64";
220 #elif defined(ARM)
221 static char cpu_arch[] = "arm";
222 #elif defined(PPC)
223 static char cpu_arch[] = "ppc";
224 #elif defined(SPARC)
225 # ifdef _LP64
226 static char cpu_arch[] = "sparcv9";
227 # else
228 static char cpu_arch[] = "sparc";
229 # endif
230 #else
231 #error Add appropriate cpu_arch setting
232 #endif
234 // Compiler variant
235 #ifdef COMPILER2
236 #define COMPILER_VARIANT "server"
237 #else
238 #define COMPILER_VARIANT "client"
239 #endif
242 void os::Bsd::initialize_system_info() {
243 int mib[2];
244 size_t len;
245 int cpu_val;
246 julong mem_val;
248 /* get processors count via hw.ncpus sysctl */
249 mib[0] = CTL_HW;
250 mib[1] = HW_NCPU;
251 len = sizeof(cpu_val);
252 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
253 assert(len == sizeof(cpu_val), "unexpected data size");
254 set_processor_count(cpu_val);
255 }
256 else {
257 set_processor_count(1); // fallback
258 }
260 /* get physical memory via hw.memsize sysctl (hw.memsize is used
261 * since it returns a 64 bit value)
262 */
263 mib[0] = CTL_HW;
265 #if defined (HW_MEMSIZE) // Apple
266 mib[1] = HW_MEMSIZE;
267 #elif defined(HW_PHYSMEM) // Most of BSD
268 mib[1] = HW_PHYSMEM;
269 #elif defined(HW_REALMEM) // Old FreeBSD
270 mib[1] = HW_REALMEM;
271 #else
272 #error No ways to get physmem
273 #endif
275 len = sizeof(mem_val);
276 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
277 assert(len == sizeof(mem_val), "unexpected data size");
278 _physical_memory = mem_val;
279 } else {
280 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
281 }
283 #ifdef __OpenBSD__
284 {
285 // limit _physical_memory memory view on OpenBSD since
286 // datasize rlimit restricts us anyway.
287 struct rlimit limits;
288 getrlimit(RLIMIT_DATA, &limits);
289 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
290 }
291 #endif
292 }
294 #ifdef __APPLE__
295 static const char *get_home() {
296 const char *home_dir = ::getenv("HOME");
297 if ((home_dir == NULL) || (*home_dir == '\0')) {
298 struct passwd *passwd_info = getpwuid(geteuid());
299 if (passwd_info != NULL) {
300 home_dir = passwd_info->pw_dir;
301 }
302 }
304 return home_dir;
305 }
306 #endif
308 void os::init_system_properties_values() {
309 // char arch[12];
310 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
312 // The next steps are taken in the product version:
313 //
314 // Obtain the JAVA_HOME value from the location of libjvm.so.
315 // This library should be located at:
316 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
317 //
318 // If "/jre/lib/" appears at the right place in the path, then we
319 // assume libjvm.so is installed in a JDK and we use this path.
320 //
321 // Otherwise exit with message: "Could not create the Java virtual machine."
322 //
323 // The following extra steps are taken in the debugging version:
324 //
325 // If "/jre/lib/" does NOT appear at the right place in the path
326 // instead of exit check for $JAVA_HOME environment variable.
327 //
328 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
329 // then we append a fake suffix "hotspot/libjvm.so" to this path so
330 // it looks like libjvm.so is installed there
331 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
332 //
333 // Otherwise exit.
334 //
335 // Important note: if the location of libjvm.so changes this
336 // code needs to be changed accordingly.
338 // The next few definitions allow the code to be verbatim:
339 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
340 #define getenv(n) ::getenv(n)
342 /*
343 * See ld(1):
344 * The linker uses the following search paths to locate required
345 * shared libraries:
346 * 1: ...
347 * ...
348 * 7: The default directories, normally /lib and /usr/lib.
349 */
350 #ifndef DEFAULT_LIBPATH
351 #define DEFAULT_LIBPATH "/lib:/usr/lib"
352 #endif
354 #define EXTENSIONS_DIR "/lib/ext"
355 #define ENDORSED_DIR "/lib/endorsed"
356 #define REG_DIR "/usr/java/packages"
358 #ifdef __APPLE__
359 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
360 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
361 const char *user_home_dir = get_home();
362 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
363 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
364 sizeof(SYS_EXTENSIONS_DIRS);
365 #endif
367 {
368 /* sysclasspath, java_home, dll_dir */
369 {
370 char *home_path;
371 char *dll_path;
372 char *pslash;
373 char buf[MAXPATHLEN];
374 os::jvm_path(buf, sizeof(buf));
376 // Found the full path to libjvm.so.
377 // Now cut the path to <java_home>/jre if we can.
378 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
379 pslash = strrchr(buf, '/');
380 if (pslash != NULL)
381 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
382 dll_path = malloc(strlen(buf) + 1);
383 if (dll_path == NULL)
384 return;
385 strcpy(dll_path, buf);
386 Arguments::set_dll_dir(dll_path);
388 if (pslash != NULL) {
389 pslash = strrchr(buf, '/');
390 if (pslash != NULL) {
391 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
392 #ifndef __APPLE__
393 pslash = strrchr(buf, '/');
394 if (pslash != NULL)
395 *pslash = '\0'; /* get rid of /lib */
396 #endif
397 }
398 }
400 home_path = malloc(strlen(buf) + 1);
401 if (home_path == NULL)
402 return;
403 strcpy(home_path, buf);
404 Arguments::set_java_home(home_path);
406 if (!set_boot_path('/', ':'))
407 return;
408 }
410 /*
411 * Where to look for native libraries
412 *
413 * Note: Due to a legacy implementation, most of the library path
414 * is set in the launcher. This was to accomodate linking restrictions
415 * on legacy Bsd implementations (which are no longer supported).
416 * Eventually, all the library path setting will be done here.
417 *
418 * However, to prevent the proliferation of improperly built native
419 * libraries, the new path component /usr/java/packages is added here.
420 * Eventually, all the library path setting will be done here.
421 */
422 {
423 char *ld_library_path;
425 /*
426 * Construct the invariant part of ld_library_path. Note that the
427 * space for the colon and the trailing null are provided by the
428 * nulls included by the sizeof operator (so actually we allocate
429 * a byte more than necessary).
430 */
431 #ifdef __APPLE__
432 ld_library_path = (char *) malloc(system_ext_size);
433 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
434 #else
435 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
436 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
437 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
438 #endif
440 /*
441 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
442 * should always exist (until the legacy problem cited above is
443 * addressed).
444 */
445 #ifdef __APPLE__
446 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
447 char *l = getenv("JAVA_LIBRARY_PATH");
448 if (l != NULL) {
449 char *t = ld_library_path;
450 /* That's +1 for the colon and +1 for the trailing '\0' */
451 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
452 sprintf(ld_library_path, "%s:%s", l, t);
453 free(t);
454 }
456 char *v = getenv("DYLD_LIBRARY_PATH");
457 #else
458 char *v = getenv("LD_LIBRARY_PATH");
459 #endif
460 if (v != NULL) {
461 char *t = ld_library_path;
462 /* That's +1 for the colon and +1 for the trailing '\0' */
463 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
464 sprintf(ld_library_path, "%s:%s", v, t);
465 free(t);
466 }
468 #ifdef __APPLE__
469 // Apple's Java6 has "." at the beginning of java.library.path.
470 // OpenJDK on Windows has "." at the end of java.library.path.
471 // OpenJDK on Linux and Solaris don't have "." in java.library.path
472 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
473 // "." is appended to the end of java.library.path. Yes, this
474 // could cause a change in behavior, but Apple's Java6 behavior
475 // can be achieved by putting "." at the beginning of the
476 // JAVA_LIBRARY_PATH environment variable.
477 {
478 char *t = ld_library_path;
479 // that's +3 for appending ":." and the trailing '\0'
480 ld_library_path = (char *) malloc(strlen(t) + 3);
481 sprintf(ld_library_path, "%s:%s", t, ".");
482 free(t);
483 }
484 #endif
486 Arguments::set_library_path(ld_library_path);
487 }
489 /*
490 * Extensions directories.
491 *
492 * Note that the space for the colon and the trailing null are provided
493 * by the nulls included by the sizeof operator (so actually one byte more
494 * than necessary is allocated).
495 */
496 {
497 #ifdef __APPLE__
498 char *buf = malloc(strlen(Arguments::get_java_home()) +
499 sizeof(EXTENSIONS_DIR) + system_ext_size);
500 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
501 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
502 #else
503 char *buf = malloc(strlen(Arguments::get_java_home()) +
504 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
505 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
506 Arguments::get_java_home());
507 #endif
509 Arguments::set_ext_dirs(buf);
510 }
512 /* Endorsed standards default directory. */
513 {
514 char * buf;
515 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
516 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
517 Arguments::set_endorsed_dirs(buf);
518 }
519 }
521 #ifdef __APPLE__
522 #undef SYS_EXTENSIONS_DIR
523 #endif
524 #undef malloc
525 #undef getenv
526 #undef EXTENSIONS_DIR
527 #undef ENDORSED_DIR
529 // Done
530 return;
531 }
533 ////////////////////////////////////////////////////////////////////////////////
534 // breakpoint support
536 void os::breakpoint() {
537 BREAKPOINT;
538 }
540 extern "C" void breakpoint() {
541 // use debugger to set breakpoint here
542 }
544 ////////////////////////////////////////////////////////////////////////////////
545 // signal support
547 debug_only(static bool signal_sets_initialized = false);
548 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
550 bool os::Bsd::is_sig_ignored(int sig) {
551 struct sigaction oact;
552 sigaction(sig, (struct sigaction*)NULL, &oact);
553 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
554 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
555 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
556 return true;
557 else
558 return false;
559 }
561 void os::Bsd::signal_sets_init() {
562 // Should also have an assertion stating we are still single-threaded.
563 assert(!signal_sets_initialized, "Already initialized");
564 // Fill in signals that are necessarily unblocked for all threads in
565 // the VM. Currently, we unblock the following signals:
566 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
567 // by -Xrs (=ReduceSignalUsage));
568 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
569 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
570 // the dispositions or masks wrt these signals.
571 // Programs embedding the VM that want to use the above signals for their
572 // own purposes must, at this time, use the "-Xrs" option to prevent
573 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
574 // (See bug 4345157, and other related bugs).
575 // In reality, though, unblocking these signals is really a nop, since
576 // these signals are not blocked by default.
577 sigemptyset(&unblocked_sigs);
578 sigemptyset(&allowdebug_blocked_sigs);
579 sigaddset(&unblocked_sigs, SIGILL);
580 sigaddset(&unblocked_sigs, SIGSEGV);
581 sigaddset(&unblocked_sigs, SIGBUS);
582 sigaddset(&unblocked_sigs, SIGFPE);
583 sigaddset(&unblocked_sigs, SR_signum);
585 if (!ReduceSignalUsage) {
586 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
587 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
588 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
589 }
590 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
591 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
592 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
593 }
594 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
595 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
596 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
597 }
598 }
599 // Fill in signals that are blocked by all but the VM thread.
600 sigemptyset(&vm_sigs);
601 if (!ReduceSignalUsage)
602 sigaddset(&vm_sigs, BREAK_SIGNAL);
603 debug_only(signal_sets_initialized = true);
605 }
607 // These are signals that are unblocked while a thread is running Java.
608 // (For some reason, they get blocked by default.)
609 sigset_t* os::Bsd::unblocked_signals() {
610 assert(signal_sets_initialized, "Not initialized");
611 return &unblocked_sigs;
612 }
614 // These are the signals that are blocked while a (non-VM) thread is
615 // running Java. Only the VM thread handles these signals.
616 sigset_t* os::Bsd::vm_signals() {
617 assert(signal_sets_initialized, "Not initialized");
618 return &vm_sigs;
619 }
621 // These are signals that are blocked during cond_wait to allow debugger in
622 sigset_t* os::Bsd::allowdebug_blocked_signals() {
623 assert(signal_sets_initialized, "Not initialized");
624 return &allowdebug_blocked_sigs;
625 }
627 void os::Bsd::hotspot_sigmask(Thread* thread) {
629 //Save caller's signal mask before setting VM signal mask
630 sigset_t caller_sigmask;
631 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
633 OSThread* osthread = thread->osthread();
634 osthread->set_caller_sigmask(caller_sigmask);
636 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
638 if (!ReduceSignalUsage) {
639 if (thread->is_VM_thread()) {
640 // Only the VM thread handles BREAK_SIGNAL ...
641 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
642 } else {
643 // ... all other threads block BREAK_SIGNAL
644 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
645 }
646 }
647 }
650 //////////////////////////////////////////////////////////////////////////////
651 // create new thread
653 // check if it's safe to start a new thread
654 static bool _thread_safety_check(Thread* thread) {
655 return true;
656 }
658 #ifdef __APPLE__
659 // library handle for calling objc_registerThreadWithCollector()
660 // without static linking to the libobjc library
661 #define OBJC_LIB "/usr/lib/libobjc.dylib"
662 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
663 typedef void (*objc_registerThreadWithCollector_t)();
664 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
665 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
666 #endif
668 #ifdef __APPLE__
669 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
670 // Additional thread_id used to correlate threads in SA
671 thread_identifier_info_data_t m_ident_info;
672 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
674 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
675 (thread_info_t) &m_ident_info, &count);
677 return m_ident_info.thread_id;
678 }
679 #endif
681 // Thread start routine for all newly created threads
682 static void *java_start(Thread *thread) {
683 // Try to randomize the cache line index of hot stack frames.
684 // This helps when threads of the same stack traces evict each other's
685 // cache lines. The threads can be either from the same JVM instance, or
686 // from different JVM instances. The benefit is especially true for
687 // processors with hyperthreading technology.
688 static int counter = 0;
689 int pid = os::current_process_id();
690 alloca(((pid ^ counter++) & 7) * 128);
692 ThreadLocalStorage::set_thread(thread);
694 OSThread* osthread = thread->osthread();
695 Monitor* sync = osthread->startThread_lock();
697 // non floating stack BsdThreads needs extra check, see above
698 if (!_thread_safety_check(thread)) {
699 // notify parent thread
700 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
701 osthread->set_state(ZOMBIE);
702 sync->notify_all();
703 return NULL;
704 }
706 osthread->set_thread_id(os::Bsd::gettid());
708 #ifdef __APPLE__
709 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
710 guarantee(unique_thread_id != 0, "unique thread id was not found");
711 osthread->set_unique_thread_id(unique_thread_id);
712 #endif
713 // initialize signal mask for this thread
714 os::Bsd::hotspot_sigmask(thread);
716 // initialize floating point control register
717 os::Bsd::init_thread_fpu_state();
719 #ifdef __APPLE__
720 // register thread with objc gc
721 if (objc_registerThreadWithCollectorFunction != NULL) {
722 objc_registerThreadWithCollectorFunction();
723 }
724 #endif
726 // handshaking with parent thread
727 {
728 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
730 // notify parent thread
731 osthread->set_state(INITIALIZED);
732 sync->notify_all();
734 // wait until os::start_thread()
735 while (osthread->get_state() == INITIALIZED) {
736 sync->wait(Mutex::_no_safepoint_check_flag);
737 }
738 }
740 // call one more level start routine
741 thread->run();
743 return 0;
744 }
746 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
747 assert(thread->osthread() == NULL, "caller responsible");
749 // Allocate the OSThread object
750 OSThread* osthread = new OSThread(NULL, NULL);
751 if (osthread == NULL) {
752 return false;
753 }
755 // set the correct thread state
756 osthread->set_thread_type(thr_type);
758 // Initial state is ALLOCATED but not INITIALIZED
759 osthread->set_state(ALLOCATED);
761 thread->set_osthread(osthread);
763 // init thread attributes
764 pthread_attr_t attr;
765 pthread_attr_init(&attr);
766 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
768 // stack size
769 if (os::Bsd::supports_variable_stack_size()) {
770 // calculate stack size if it's not specified by caller
771 if (stack_size == 0) {
772 stack_size = os::Bsd::default_stack_size(thr_type);
774 switch (thr_type) {
775 case os::java_thread:
776 // Java threads use ThreadStackSize which default value can be
777 // changed with the flag -Xss
778 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
779 stack_size = JavaThread::stack_size_at_create();
780 break;
781 case os::compiler_thread:
782 if (CompilerThreadStackSize > 0) {
783 stack_size = (size_t)(CompilerThreadStackSize * K);
784 break;
785 } // else fall through:
786 // use VMThreadStackSize if CompilerThreadStackSize is not defined
787 case os::vm_thread:
788 case os::pgc_thread:
789 case os::cgc_thread:
790 case os::watcher_thread:
791 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
792 break;
793 }
794 }
796 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
797 pthread_attr_setstacksize(&attr, stack_size);
798 } else {
799 // let pthread_create() pick the default value.
800 }
802 ThreadState state;
804 {
805 pthread_t tid;
806 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
808 pthread_attr_destroy(&attr);
810 if (ret != 0) {
811 if (PrintMiscellaneous && (Verbose || WizardMode)) {
812 perror("pthread_create()");
813 }
814 // Need to clean up stuff we've allocated so far
815 thread->set_osthread(NULL);
816 delete osthread;
817 return false;
818 }
820 // Store pthread info into the OSThread
821 osthread->set_pthread_id(tid);
823 // Wait until child thread is either initialized or aborted
824 {
825 Monitor* sync_with_child = osthread->startThread_lock();
826 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
827 while ((state = osthread->get_state()) == ALLOCATED) {
828 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
829 }
830 }
832 }
834 // Aborted due to thread limit being reached
835 if (state == ZOMBIE) {
836 thread->set_osthread(NULL);
837 delete osthread;
838 return false;
839 }
841 // The thread is returned suspended (in state INITIALIZED),
842 // and is started higher up in the call chain
843 assert(state == INITIALIZED, "race condition");
844 return true;
845 }
847 /////////////////////////////////////////////////////////////////////////////
848 // attach existing thread
850 // bootstrap the main thread
851 bool os::create_main_thread(JavaThread* thread) {
852 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
853 return create_attached_thread(thread);
854 }
856 bool os::create_attached_thread(JavaThread* thread) {
857 #ifdef ASSERT
858 thread->verify_not_published();
859 #endif
861 // Allocate the OSThread object
862 OSThread* osthread = new OSThread(NULL, NULL);
864 if (osthread == NULL) {
865 return false;
866 }
868 osthread->set_thread_id(os::Bsd::gettid());
870 // Store pthread info into the OSThread
871 #ifdef __APPLE__
872 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
873 guarantee(unique_thread_id != 0, "just checking");
874 osthread->set_unique_thread_id(unique_thread_id);
875 #endif
876 osthread->set_pthread_id(::pthread_self());
878 // initialize floating point control register
879 os::Bsd::init_thread_fpu_state();
881 // Initial thread state is RUNNABLE
882 osthread->set_state(RUNNABLE);
884 thread->set_osthread(osthread);
886 // initialize signal mask for this thread
887 // and save the caller's signal mask
888 os::Bsd::hotspot_sigmask(thread);
890 return true;
891 }
893 void os::pd_start_thread(Thread* thread) {
894 OSThread * osthread = thread->osthread();
895 assert(osthread->get_state() != INITIALIZED, "just checking");
896 Monitor* sync_with_child = osthread->startThread_lock();
897 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
898 sync_with_child->notify();
899 }
901 // Free Bsd resources related to the OSThread
902 void os::free_thread(OSThread* osthread) {
903 assert(osthread != NULL, "osthread not set");
905 if (Thread::current()->osthread() == osthread) {
906 // Restore caller's signal mask
907 sigset_t sigmask = osthread->caller_sigmask();
908 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
909 }
911 delete osthread;
912 }
914 //////////////////////////////////////////////////////////////////////////////
915 // thread local storage
917 int os::allocate_thread_local_storage() {
918 pthread_key_t key;
919 int rslt = pthread_key_create(&key, NULL);
920 assert(rslt == 0, "cannot allocate thread local storage");
921 return (int)key;
922 }
924 // Note: This is currently not used by VM, as we don't destroy TLS key
925 // on VM exit.
926 void os::free_thread_local_storage(int index) {
927 int rslt = pthread_key_delete((pthread_key_t)index);
928 assert(rslt == 0, "invalid index");
929 }
931 void os::thread_local_storage_at_put(int index, void* value) {
932 int rslt = pthread_setspecific((pthread_key_t)index, value);
933 assert(rslt == 0, "pthread_setspecific failed");
934 }
936 extern "C" Thread* get_thread() {
937 return ThreadLocalStorage::thread();
938 }
941 ////////////////////////////////////////////////////////////////////////////////
942 // time support
944 // Time since start-up in seconds to a fine granularity.
945 // Used by VMSelfDestructTimer and the MemProfiler.
946 double os::elapsedTime() {
948 return (double)(os::elapsed_counter()) * 0.000001;
949 }
951 jlong os::elapsed_counter() {
952 timeval time;
953 int status = gettimeofday(&time, NULL);
954 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
955 }
957 jlong os::elapsed_frequency() {
958 return (1000 * 1000);
959 }
961 bool os::supports_vtime() { return true; }
962 bool os::enable_vtime() { return false; }
963 bool os::vtime_enabled() { return false; }
965 double os::elapsedVTime() {
966 // better than nothing, but not much
967 return elapsedTime();
968 }
970 jlong os::javaTimeMillis() {
971 timeval time;
972 int status = gettimeofday(&time, NULL);
973 assert(status != -1, "bsd error");
974 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
975 }
977 #ifndef CLOCK_MONOTONIC
978 #define CLOCK_MONOTONIC (1)
979 #endif
981 #ifdef __APPLE__
982 void os::Bsd::clock_init() {
983 // XXXDARWIN: Investigate replacement monotonic clock
984 }
985 #else
986 void os::Bsd::clock_init() {
987 struct timespec res;
988 struct timespec tp;
989 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
990 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
991 // yes, monotonic clock is supported
992 _clock_gettime = ::clock_gettime;
993 }
994 }
995 #endif
998 jlong os::javaTimeNanos() {
999 if (Bsd::supports_monotonic_clock()) {
1000 struct timespec tp;
1001 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1002 assert(status == 0, "gettime error");
1003 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1004 return result;
1005 } else {
1006 timeval time;
1007 int status = gettimeofday(&time, NULL);
1008 assert(status != -1, "bsd error");
1009 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1010 return 1000 * usecs;
1011 }
1012 }
1014 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1015 if (Bsd::supports_monotonic_clock()) {
1016 info_ptr->max_value = ALL_64_BITS;
1018 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1019 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1020 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1021 } else {
1022 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1023 info_ptr->max_value = ALL_64_BITS;
1025 // gettimeofday is a real time clock so it skips
1026 info_ptr->may_skip_backward = true;
1027 info_ptr->may_skip_forward = true;
1028 }
1030 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1031 }
1033 // Return the real, user, and system times in seconds from an
1034 // arbitrary fixed point in the past.
1035 bool os::getTimesSecs(double* process_real_time,
1036 double* process_user_time,
1037 double* process_system_time) {
1038 struct tms ticks;
1039 clock_t real_ticks = times(&ticks);
1041 if (real_ticks == (clock_t) (-1)) {
1042 return false;
1043 } else {
1044 double ticks_per_second = (double) clock_tics_per_sec;
1045 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1046 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1047 *process_real_time = ((double) real_ticks) / ticks_per_second;
1049 return true;
1050 }
1051 }
1054 char * os::local_time_string(char *buf, size_t buflen) {
1055 struct tm t;
1056 time_t long_time;
1057 time(&long_time);
1058 localtime_r(&long_time, &t);
1059 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1060 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1061 t.tm_hour, t.tm_min, t.tm_sec);
1062 return buf;
1063 }
1065 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1066 return localtime_r(clock, res);
1067 }
1069 ////////////////////////////////////////////////////////////////////////////////
1070 // runtime exit support
1072 // Note: os::shutdown() might be called very early during initialization, or
1073 // called from signal handler. Before adding something to os::shutdown(), make
1074 // sure it is async-safe and can handle partially initialized VM.
1075 void os::shutdown() {
1077 // allow PerfMemory to attempt cleanup of any persistent resources
1078 perfMemory_exit();
1080 // needs to remove object in file system
1081 AttachListener::abort();
1083 // flush buffered output, finish log files
1084 ostream_abort();
1086 // Check for abort hook
1087 abort_hook_t abort_hook = Arguments::abort_hook();
1088 if (abort_hook != NULL) {
1089 abort_hook();
1090 }
1092 }
1094 // Note: os::abort() might be called very early during initialization, or
1095 // called from signal handler. Before adding something to os::abort(), make
1096 // sure it is async-safe and can handle partially initialized VM.
1097 void os::abort(bool dump_core) {
1098 os::shutdown();
1099 if (dump_core) {
1100 #ifndef PRODUCT
1101 fdStream out(defaultStream::output_fd());
1102 out.print_raw("Current thread is ");
1103 char buf[16];
1104 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1105 out.print_raw_cr(buf);
1106 out.print_raw_cr("Dumping core ...");
1107 #endif
1108 ::abort(); // dump core
1109 }
1111 ::exit(1);
1112 }
1114 // Die immediately, no exit hook, no abort hook, no cleanup.
1115 void os::die() {
1116 // _exit() on BsdThreads only kills current thread
1117 ::abort();
1118 }
1120 // unused on bsd for now.
1121 void os::set_error_file(const char *logfile) {}
1124 // This method is a copy of JDK's sysGetLastErrorString
1125 // from src/solaris/hpi/src/system_md.c
1127 size_t os::lasterror(char *buf, size_t len) {
1129 if (errno == 0) return 0;
1131 const char *s = ::strerror(errno);
1132 size_t n = ::strlen(s);
1133 if (n >= len) {
1134 n = len - 1;
1135 }
1136 ::strncpy(buf, s, n);
1137 buf[n] = '\0';
1138 return n;
1139 }
1141 // Information of current thread in variety of formats
1142 pid_t os::Bsd::gettid() {
1143 int retval = -1;
1145 #ifdef __APPLE__ //XNU kernel
1146 // despite the fact mach port is actually not a thread id use it
1147 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1148 retval = ::pthread_mach_thread_np(::pthread_self());
1149 guarantee(retval != 0, "just checking");
1150 return retval;
1152 #elif __FreeBSD__
1153 retval = syscall(SYS_thr_self);
1154 #elif __OpenBSD__
1155 retval = syscall(SYS_getthrid);
1156 #elif __NetBSD__
1157 retval = (pid_t) syscall(SYS__lwp_self);
1158 #endif
1160 if (retval == -1) {
1161 return getpid();
1162 }
1163 }
1165 intx os::current_thread_id() {
1166 #ifdef __APPLE__
1167 return (intx)::pthread_mach_thread_np(::pthread_self());
1168 #else
1169 return (intx)::pthread_self();
1170 #endif
1171 }
1173 int os::current_process_id() {
1175 // Under the old bsd thread library, bsd gives each thread
1176 // its own process id. Because of this each thread will return
1177 // a different pid if this method were to return the result
1178 // of getpid(2). Bsd provides no api that returns the pid
1179 // of the launcher thread for the vm. This implementation
1180 // returns a unique pid, the pid of the launcher thread
1181 // that starts the vm 'process'.
1183 // Under the NPTL, getpid() returns the same pid as the
1184 // launcher thread rather than a unique pid per thread.
1185 // Use gettid() if you want the old pre NPTL behaviour.
1187 // if you are looking for the result of a call to getpid() that
1188 // returns a unique pid for the calling thread, then look at the
1189 // OSThread::thread_id() method in osThread_bsd.hpp file
1191 return (int)(_initial_pid ? _initial_pid : getpid());
1192 }
1194 // DLL functions
1196 #define JNI_LIB_PREFIX "lib"
1197 #ifdef __APPLE__
1198 #define JNI_LIB_SUFFIX ".dylib"
1199 #else
1200 #define JNI_LIB_SUFFIX ".so"
1201 #endif
1203 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1205 // This must be hard coded because it's the system's temporary
1206 // directory not the java application's temp directory, ala java.io.tmpdir.
1207 #ifdef __APPLE__
1208 // macosx has a secure per-user temporary directory
1209 char temp_path_storage[PATH_MAX];
1210 const char* os::get_temp_directory() {
1211 static char *temp_path = NULL;
1212 if (temp_path == NULL) {
1213 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1214 if (pathSize == 0 || pathSize > PATH_MAX) {
1215 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1216 }
1217 temp_path = temp_path_storage;
1218 }
1219 return temp_path;
1220 }
1221 #else /* __APPLE__ */
1222 const char* os::get_temp_directory() { return "/tmp"; }
1223 #endif /* __APPLE__ */
1225 static bool file_exists(const char* filename) {
1226 struct stat statbuf;
1227 if (filename == NULL || strlen(filename) == 0) {
1228 return false;
1229 }
1230 return os::stat(filename, &statbuf) == 0;
1231 }
1233 bool os::dll_build_name(char* buffer, size_t buflen,
1234 const char* pname, const char* fname) {
1235 bool retval = false;
1236 // Copied from libhpi
1237 const size_t pnamelen = pname ? strlen(pname) : 0;
1239 // Return error on buffer overflow.
1240 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1241 return retval;
1242 }
1244 if (pnamelen == 0) {
1245 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1246 retval = true;
1247 } else if (strchr(pname, *os::path_separator()) != NULL) {
1248 int n;
1249 char** pelements = split_path(pname, &n);
1250 if (pelements == NULL) {
1251 return false;
1252 }
1253 for (int i = 0 ; i < n ; i++) {
1254 // Really shouldn't be NULL, but check can't hurt
1255 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1256 continue; // skip the empty path values
1257 }
1258 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1259 pelements[i], fname);
1260 if (file_exists(buffer)) {
1261 retval = true;
1262 break;
1263 }
1264 }
1265 // release the storage
1266 for (int i = 0 ; i < n ; i++) {
1267 if (pelements[i] != NULL) {
1268 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1269 }
1270 }
1271 if (pelements != NULL) {
1272 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1273 }
1274 } else {
1275 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1276 retval = true;
1277 }
1278 return retval;
1279 }
1281 // check if addr is inside libjvm.so
1282 bool os::address_is_in_vm(address addr) {
1283 static address libjvm_base_addr;
1284 Dl_info dlinfo;
1286 if (libjvm_base_addr == NULL) {
1287 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1288 libjvm_base_addr = (address)dlinfo.dli_fbase;
1289 }
1290 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1291 }
1293 if (dladdr((void *)addr, &dlinfo) != 0) {
1294 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1295 }
1297 return false;
1298 }
1301 #define MACH_MAXSYMLEN 256
1303 bool os::dll_address_to_function_name(address addr, char *buf,
1304 int buflen, int *offset) {
1305 // buf is not optional, but offset is optional
1306 assert(buf != NULL, "sanity check");
1308 Dl_info dlinfo;
1309 char localbuf[MACH_MAXSYMLEN];
1311 if (dladdr((void*)addr, &dlinfo) != 0) {
1312 // see if we have a matching symbol
1313 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1314 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1315 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1316 }
1317 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1318 return true;
1319 }
1320 // no matching symbol so try for just file info
1321 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1322 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1323 buf, buflen, offset, dlinfo.dli_fname)) {
1324 return true;
1325 }
1326 }
1328 // Handle non-dynamic manually:
1329 if (dlinfo.dli_fbase != NULL &&
1330 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1331 dlinfo.dli_fbase)) {
1332 if (!Decoder::demangle(localbuf, buf, buflen)) {
1333 jio_snprintf(buf, buflen, "%s", localbuf);
1334 }
1335 return true;
1336 }
1337 }
1338 buf[0] = '\0';
1339 if (offset != NULL) *offset = -1;
1340 return false;
1341 }
1343 // ported from solaris version
1344 bool os::dll_address_to_library_name(address addr, char* buf,
1345 int buflen, int* offset) {
1346 // buf is not optional, but offset is optional
1347 assert(buf != NULL, "sanity check");
1349 Dl_info dlinfo;
1351 if (dladdr((void*)addr, &dlinfo) != 0) {
1352 if (dlinfo.dli_fname != NULL) {
1353 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1354 }
1355 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1356 *offset = addr - (address)dlinfo.dli_fbase;
1357 }
1358 return true;
1359 }
1361 buf[0] = '\0';
1362 if (offset) *offset = -1;
1363 return false;
1364 }
1366 // Loads .dll/.so and
1367 // in case of error it checks if .dll/.so was built for the
1368 // same architecture as Hotspot is running on
1370 #ifdef __APPLE__
1371 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1372 void * result= ::dlopen(filename, RTLD_LAZY);
1373 if (result != NULL) {
1374 // Successful loading
1375 return result;
1376 }
1378 // Read system error message into ebuf
1379 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1380 ebuf[ebuflen-1]='\0';
1382 return NULL;
1383 }
1384 #else
1385 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1386 {
1387 void * result= ::dlopen(filename, RTLD_LAZY);
1388 if (result != NULL) {
1389 // Successful loading
1390 return result;
1391 }
1393 Elf32_Ehdr elf_head;
1395 // Read system error message into ebuf
1396 // It may or may not be overwritten below
1397 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1398 ebuf[ebuflen-1]='\0';
1399 int diag_msg_max_length=ebuflen-strlen(ebuf);
1400 char* diag_msg_buf=ebuf+strlen(ebuf);
1402 if (diag_msg_max_length==0) {
1403 // No more space in ebuf for additional diagnostics message
1404 return NULL;
1405 }
1408 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1410 if (file_descriptor < 0) {
1411 // Can't open library, report dlerror() message
1412 return NULL;
1413 }
1415 bool failed_to_read_elf_head=
1416 (sizeof(elf_head)!=
1417 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1419 ::close(file_descriptor);
1420 if (failed_to_read_elf_head) {
1421 // file i/o error - report dlerror() msg
1422 return NULL;
1423 }
1425 typedef struct {
1426 Elf32_Half code; // Actual value as defined in elf.h
1427 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1428 char elf_class; // 32 or 64 bit
1429 char endianess; // MSB or LSB
1430 char* name; // String representation
1431 } arch_t;
1433 #ifndef EM_486
1434 #define EM_486 6 /* Intel 80486 */
1435 #endif
1437 #ifndef EM_MIPS_RS3_LE
1438 #define EM_MIPS_RS3_LE 10 /* MIPS */
1439 #endif
1441 #ifndef EM_PPC64
1442 #define EM_PPC64 21 /* PowerPC64 */
1443 #endif
1445 #ifndef EM_S390
1446 #define EM_S390 22 /* IBM System/390 */
1447 #endif
1449 #ifndef EM_IA_64
1450 #define EM_IA_64 50 /* HP/Intel IA-64 */
1451 #endif
1453 #ifndef EM_X86_64
1454 #define EM_X86_64 62 /* AMD x86-64 */
1455 #endif
1457 static const arch_t arch_array[]={
1458 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1459 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1460 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1461 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1462 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1463 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1464 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1465 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1466 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1467 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1468 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1469 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1470 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1471 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1472 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1473 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1474 };
1476 #if (defined IA32)
1477 static Elf32_Half running_arch_code=EM_386;
1478 #elif (defined AMD64)
1479 static Elf32_Half running_arch_code=EM_X86_64;
1480 #elif (defined IA64)
1481 static Elf32_Half running_arch_code=EM_IA_64;
1482 #elif (defined __sparc) && (defined _LP64)
1483 static Elf32_Half running_arch_code=EM_SPARCV9;
1484 #elif (defined __sparc) && (!defined _LP64)
1485 static Elf32_Half running_arch_code=EM_SPARC;
1486 #elif (defined __powerpc64__)
1487 static Elf32_Half running_arch_code=EM_PPC64;
1488 #elif (defined __powerpc__)
1489 static Elf32_Half running_arch_code=EM_PPC;
1490 #elif (defined ARM)
1491 static Elf32_Half running_arch_code=EM_ARM;
1492 #elif (defined S390)
1493 static Elf32_Half running_arch_code=EM_S390;
1494 #elif (defined ALPHA)
1495 static Elf32_Half running_arch_code=EM_ALPHA;
1496 #elif (defined MIPSEL)
1497 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1498 #elif (defined PARISC)
1499 static Elf32_Half running_arch_code=EM_PARISC;
1500 #elif (defined MIPS)
1501 static Elf32_Half running_arch_code=EM_MIPS;
1502 #elif (defined M68K)
1503 static Elf32_Half running_arch_code=EM_68K;
1504 #else
1505 #error Method os::dll_load requires that one of following is defined:\
1506 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1507 #endif
1509 // Identify compatability class for VM's architecture and library's architecture
1510 // Obtain string descriptions for architectures
1512 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1513 int running_arch_index=-1;
1515 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1516 if (running_arch_code == arch_array[i].code) {
1517 running_arch_index = i;
1518 }
1519 if (lib_arch.code == arch_array[i].code) {
1520 lib_arch.compat_class = arch_array[i].compat_class;
1521 lib_arch.name = arch_array[i].name;
1522 }
1523 }
1525 assert(running_arch_index != -1,
1526 "Didn't find running architecture code (running_arch_code) in arch_array");
1527 if (running_arch_index == -1) {
1528 // Even though running architecture detection failed
1529 // we may still continue with reporting dlerror() message
1530 return NULL;
1531 }
1533 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1534 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1535 return NULL;
1536 }
1538 #ifndef S390
1539 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1540 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1541 return NULL;
1542 }
1543 #endif // !S390
1545 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1546 if ( lib_arch.name!=NULL ) {
1547 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1548 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1549 lib_arch.name, arch_array[running_arch_index].name);
1550 } else {
1551 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1552 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1553 lib_arch.code,
1554 arch_array[running_arch_index].name);
1555 }
1556 }
1558 return NULL;
1559 }
1560 #endif /* !__APPLE__ */
1562 // XXX: Do we need a lock around this as per Linux?
1563 void* os::dll_lookup(void* handle, const char* name) {
1564 return dlsym(handle, name);
1565 }
1568 static bool _print_ascii_file(const char* filename, outputStream* st) {
1569 int fd = ::open(filename, O_RDONLY);
1570 if (fd == -1) {
1571 return false;
1572 }
1574 char buf[32];
1575 int bytes;
1576 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1577 st->print_raw(buf, bytes);
1578 }
1580 ::close(fd);
1582 return true;
1583 }
1585 void os::print_dll_info(outputStream *st) {
1586 st->print_cr("Dynamic libraries:");
1587 #ifdef RTLD_DI_LINKMAP
1588 Dl_info dli;
1589 void *handle;
1590 Link_map *map;
1591 Link_map *p;
1593 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1594 dli.dli_fname == NULL) {
1595 st->print_cr("Error: Cannot print dynamic libraries.");
1596 return;
1597 }
1598 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1599 if (handle == NULL) {
1600 st->print_cr("Error: Cannot print dynamic libraries.");
1601 return;
1602 }
1603 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1604 if (map == NULL) {
1605 st->print_cr("Error: Cannot print dynamic libraries.");
1606 return;
1607 }
1609 while (map->l_prev != NULL)
1610 map = map->l_prev;
1612 while (map != NULL) {
1613 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1614 map = map->l_next;
1615 }
1617 dlclose(handle);
1618 #elif defined(__APPLE__)
1619 uint32_t count;
1620 uint32_t i;
1622 count = _dyld_image_count();
1623 for (i = 1; i < count; i++) {
1624 const char *name = _dyld_get_image_name(i);
1625 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1626 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1627 }
1628 #else
1629 st->print_cr("Error: Cannot print dynamic libraries.");
1630 #endif
1631 }
1633 void os::print_os_info_brief(outputStream* st) {
1634 st->print("Bsd");
1636 os::Posix::print_uname_info(st);
1637 }
1639 void os::print_os_info(outputStream* st) {
1640 st->print("OS:");
1641 st->print("Bsd");
1643 os::Posix::print_uname_info(st);
1645 os::Posix::print_rlimit_info(st);
1647 os::Posix::print_load_average(st);
1648 }
1650 void os::pd_print_cpu_info(outputStream* st) {
1651 // Nothing to do for now.
1652 }
1654 void os::print_memory_info(outputStream* st) {
1656 st->print("Memory:");
1657 st->print(" %dk page", os::vm_page_size()>>10);
1659 st->print(", physical " UINT64_FORMAT "k",
1660 os::physical_memory() >> 10);
1661 st->print("(" UINT64_FORMAT "k free)",
1662 os::available_memory() >> 10);
1663 st->cr();
1665 // meminfo
1666 st->print("\n/proc/meminfo:\n");
1667 _print_ascii_file("/proc/meminfo", st);
1668 st->cr();
1669 }
1671 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1672 // but they're the same for all the bsd arch that we support
1673 // and they're the same for solaris but there's no common place to put this.
1674 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1675 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1676 "ILL_COPROC", "ILL_BADSTK" };
1678 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1679 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1680 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1682 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1684 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1686 void os::print_siginfo(outputStream* st, void* siginfo) {
1687 st->print("siginfo:");
1689 const int buflen = 100;
1690 char buf[buflen];
1691 siginfo_t *si = (siginfo_t*)siginfo;
1692 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1693 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1694 st->print("si_errno=%s", buf);
1695 } else {
1696 st->print("si_errno=%d", si->si_errno);
1697 }
1698 const int c = si->si_code;
1699 assert(c > 0, "unexpected si_code");
1700 switch (si->si_signo) {
1701 case SIGILL:
1702 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1703 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1704 break;
1705 case SIGFPE:
1706 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1707 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1708 break;
1709 case SIGSEGV:
1710 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1711 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1712 break;
1713 case SIGBUS:
1714 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1715 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1716 break;
1717 default:
1718 st->print(", si_code=%d", si->si_code);
1719 // no si_addr
1720 }
1722 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1723 UseSharedSpaces) {
1724 FileMapInfo* mapinfo = FileMapInfo::current_info();
1725 if (mapinfo->is_in_shared_space(si->si_addr)) {
1726 st->print("\n\nError accessing class data sharing archive." \
1727 " Mapped file inaccessible during execution, " \
1728 " possible disk/network problem.");
1729 }
1730 }
1731 st->cr();
1732 }
1735 static void print_signal_handler(outputStream* st, int sig,
1736 char* buf, size_t buflen);
1738 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1739 st->print_cr("Signal Handlers:");
1740 print_signal_handler(st, SIGSEGV, buf, buflen);
1741 print_signal_handler(st, SIGBUS , buf, buflen);
1742 print_signal_handler(st, SIGFPE , buf, buflen);
1743 print_signal_handler(st, SIGPIPE, buf, buflen);
1744 print_signal_handler(st, SIGXFSZ, buf, buflen);
1745 print_signal_handler(st, SIGILL , buf, buflen);
1746 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1747 print_signal_handler(st, SR_signum, buf, buflen);
1748 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1749 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1750 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1751 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1752 }
1754 static char saved_jvm_path[MAXPATHLEN] = {0};
1756 // Find the full path to the current module, libjvm
1757 void os::jvm_path(char *buf, jint buflen) {
1758 // Error checking.
1759 if (buflen < MAXPATHLEN) {
1760 assert(false, "must use a large-enough buffer");
1761 buf[0] = '\0';
1762 return;
1763 }
1764 // Lazy resolve the path to current module.
1765 if (saved_jvm_path[0] != 0) {
1766 strcpy(buf, saved_jvm_path);
1767 return;
1768 }
1770 char dli_fname[MAXPATHLEN];
1771 bool ret = dll_address_to_library_name(
1772 CAST_FROM_FN_PTR(address, os::jvm_path),
1773 dli_fname, sizeof(dli_fname), NULL);
1774 assert(ret, "cannot locate libjvm");
1775 char *rp = NULL;
1776 if (ret && dli_fname[0] != '\0') {
1777 rp = realpath(dli_fname, buf);
1778 }
1779 if (rp == NULL)
1780 return;
1782 if (Arguments::created_by_gamma_launcher()) {
1783 // Support for the gamma launcher. Typical value for buf is
1784 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1785 // the right place in the string, then assume we are installed in a JDK and
1786 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1787 // construct a path to the JVM being overridden.
1789 const char *p = buf + strlen(buf) - 1;
1790 for (int count = 0; p > buf && count < 5; ++count) {
1791 for (--p; p > buf && *p != '/'; --p)
1792 /* empty */ ;
1793 }
1795 if (strncmp(p, "/jre/lib/", 9) != 0) {
1796 // Look for JAVA_HOME in the environment.
1797 char* java_home_var = ::getenv("JAVA_HOME");
1798 if (java_home_var != NULL && java_home_var[0] != 0) {
1799 char* jrelib_p;
1800 int len;
1802 // Check the current module name "libjvm"
1803 p = strrchr(buf, '/');
1804 assert(strstr(p, "/libjvm") == p, "invalid library name");
1806 rp = realpath(java_home_var, buf);
1807 if (rp == NULL)
1808 return;
1810 // determine if this is a legacy image or modules image
1811 // modules image doesn't have "jre" subdirectory
1812 len = strlen(buf);
1813 jrelib_p = buf + len;
1815 // Add the appropriate library subdir
1816 snprintf(jrelib_p, buflen-len, "/jre/lib");
1817 if (0 != access(buf, F_OK)) {
1818 snprintf(jrelib_p, buflen-len, "/lib");
1819 }
1821 // Add the appropriate client or server subdir
1822 len = strlen(buf);
1823 jrelib_p = buf + len;
1824 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1825 if (0 != access(buf, F_OK)) {
1826 snprintf(jrelib_p, buflen-len, "");
1827 }
1829 // If the path exists within JAVA_HOME, add the JVM library name
1830 // to complete the path to JVM being overridden. Otherwise fallback
1831 // to the path to the current library.
1832 if (0 == access(buf, F_OK)) {
1833 // Use current module name "libjvm"
1834 len = strlen(buf);
1835 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1836 } else {
1837 // Fall back to path of current library
1838 rp = realpath(dli_fname, buf);
1839 if (rp == NULL)
1840 return;
1841 }
1842 }
1843 }
1844 }
1846 strcpy(saved_jvm_path, buf);
1847 }
1849 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1850 // no prefix required, not even "_"
1851 }
1853 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1854 // no suffix required
1855 }
1857 ////////////////////////////////////////////////////////////////////////////////
1858 // sun.misc.Signal support
1860 static volatile jint sigint_count = 0;
1862 static void
1863 UserHandler(int sig, void *siginfo, void *context) {
1864 // 4511530 - sem_post is serialized and handled by the manager thread. When
1865 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1866 // don't want to flood the manager thread with sem_post requests.
1867 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1868 return;
1870 // Ctrl-C is pressed during error reporting, likely because the error
1871 // handler fails to abort. Let VM die immediately.
1872 if (sig == SIGINT && is_error_reported()) {
1873 os::die();
1874 }
1876 os::signal_notify(sig);
1877 }
1879 void* os::user_handler() {
1880 return CAST_FROM_FN_PTR(void*, UserHandler);
1881 }
1883 extern "C" {
1884 typedef void (*sa_handler_t)(int);
1885 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1886 }
1888 void* os::signal(int signal_number, void* handler) {
1889 struct sigaction sigAct, oldSigAct;
1891 sigfillset(&(sigAct.sa_mask));
1892 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1893 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1895 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1896 // -1 means registration failed
1897 return (void *)-1;
1898 }
1900 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1901 }
1903 void os::signal_raise(int signal_number) {
1904 ::raise(signal_number);
1905 }
1907 /*
1908 * The following code is moved from os.cpp for making this
1909 * code platform specific, which it is by its very nature.
1910 */
1912 // Will be modified when max signal is changed to be dynamic
1913 int os::sigexitnum_pd() {
1914 return NSIG;
1915 }
1917 // a counter for each possible signal value
1918 static volatile jint pending_signals[NSIG+1] = { 0 };
1920 // Bsd(POSIX) specific hand shaking semaphore.
1921 #ifdef __APPLE__
1922 typedef semaphore_t os_semaphore_t;
1923 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1924 #define SEM_WAIT(sem) semaphore_wait(sem)
1925 #define SEM_POST(sem) semaphore_signal(sem)
1926 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1927 #else
1928 typedef sem_t os_semaphore_t;
1929 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1930 #define SEM_WAIT(sem) sem_wait(&sem)
1931 #define SEM_POST(sem) sem_post(&sem)
1932 #define SEM_DESTROY(sem) sem_destroy(&sem)
1933 #endif
1935 class Semaphore : public StackObj {
1936 public:
1937 Semaphore();
1938 ~Semaphore();
1939 void signal();
1940 void wait();
1941 bool trywait();
1942 bool timedwait(unsigned int sec, int nsec);
1943 private:
1944 jlong currenttime() const;
1945 os_semaphore_t _semaphore;
1946 };
1948 Semaphore::Semaphore() : _semaphore(0) {
1949 SEM_INIT(_semaphore, 0);
1950 }
1952 Semaphore::~Semaphore() {
1953 SEM_DESTROY(_semaphore);
1954 }
1956 void Semaphore::signal() {
1957 SEM_POST(_semaphore);
1958 }
1960 void Semaphore::wait() {
1961 SEM_WAIT(_semaphore);
1962 }
1964 jlong Semaphore::currenttime() const {
1965 struct timeval tv;
1966 gettimeofday(&tv, NULL);
1967 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1968 }
1970 #ifdef __APPLE__
1971 bool Semaphore::trywait() {
1972 return timedwait(0, 0);
1973 }
1975 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1976 kern_return_t kr = KERN_ABORTED;
1977 mach_timespec_t waitspec;
1978 waitspec.tv_sec = sec;
1979 waitspec.tv_nsec = nsec;
1981 jlong starttime = currenttime();
1983 kr = semaphore_timedwait(_semaphore, waitspec);
1984 while (kr == KERN_ABORTED) {
1985 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1987 jlong current = currenttime();
1988 jlong passedtime = current - starttime;
1990 if (passedtime >= totalwait) {
1991 waitspec.tv_sec = 0;
1992 waitspec.tv_nsec = 0;
1993 } else {
1994 jlong waittime = totalwait - (current - starttime);
1995 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1996 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1997 }
1999 kr = semaphore_timedwait(_semaphore, waitspec);
2000 }
2002 return kr == KERN_SUCCESS;
2003 }
2005 #else
2007 bool Semaphore::trywait() {
2008 return sem_trywait(&_semaphore) == 0;
2009 }
2011 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2012 struct timespec ts;
2013 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2015 while (1) {
2016 int result = sem_timedwait(&_semaphore, &ts);
2017 if (result == 0) {
2018 return true;
2019 } else if (errno == EINTR) {
2020 continue;
2021 } else if (errno == ETIMEDOUT) {
2022 return false;
2023 } else {
2024 return false;
2025 }
2026 }
2027 }
2029 #endif // __APPLE__
2031 static os_semaphore_t sig_sem;
2032 static Semaphore sr_semaphore;
2034 void os::signal_init_pd() {
2035 // Initialize signal structures
2036 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2038 // Initialize signal semaphore
2039 ::SEM_INIT(sig_sem, 0);
2040 }
2042 void os::signal_notify(int sig) {
2043 Atomic::inc(&pending_signals[sig]);
2044 ::SEM_POST(sig_sem);
2045 }
2047 static int check_pending_signals(bool wait) {
2048 Atomic::store(0, &sigint_count);
2049 for (;;) {
2050 for (int i = 0; i < NSIG + 1; i++) {
2051 jint n = pending_signals[i];
2052 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2053 return i;
2054 }
2055 }
2056 if (!wait) {
2057 return -1;
2058 }
2059 JavaThread *thread = JavaThread::current();
2060 ThreadBlockInVM tbivm(thread);
2062 bool threadIsSuspended;
2063 do {
2064 thread->set_suspend_equivalent();
2065 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2066 ::SEM_WAIT(sig_sem);
2068 // were we externally suspended while we were waiting?
2069 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2070 if (threadIsSuspended) {
2071 //
2072 // The semaphore has been incremented, but while we were waiting
2073 // another thread suspended us. We don't want to continue running
2074 // while suspended because that would surprise the thread that
2075 // suspended us.
2076 //
2077 ::SEM_POST(sig_sem);
2079 thread->java_suspend_self();
2080 }
2081 } while (threadIsSuspended);
2082 }
2083 }
2085 int os::signal_lookup() {
2086 return check_pending_signals(false);
2087 }
2089 int os::signal_wait() {
2090 return check_pending_signals(true);
2091 }
2093 ////////////////////////////////////////////////////////////////////////////////
2094 // Virtual Memory
2096 int os::vm_page_size() {
2097 // Seems redundant as all get out
2098 assert(os::Bsd::page_size() != -1, "must call os::init");
2099 return os::Bsd::page_size();
2100 }
2102 // Solaris allocates memory by pages.
2103 int os::vm_allocation_granularity() {
2104 assert(os::Bsd::page_size() != -1, "must call os::init");
2105 return os::Bsd::page_size();
2106 }
2108 // Rationale behind this function:
2109 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2110 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2111 // samples for JITted code. Here we create private executable mapping over the code cache
2112 // and then we can use standard (well, almost, as mapping can change) way to provide
2113 // info for the reporting script by storing timestamp and location of symbol
2114 void bsd_wrap_code(char* base, size_t size) {
2115 static volatile jint cnt = 0;
2117 if (!UseOprofile) {
2118 return;
2119 }
2121 char buf[PATH_MAX + 1];
2122 int num = Atomic::add(1, &cnt);
2124 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2125 os::get_temp_directory(), os::current_process_id(), num);
2126 unlink(buf);
2128 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2130 if (fd != -1) {
2131 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2132 if (rv != (off_t)-1) {
2133 if (::write(fd, "", 1) == 1) {
2134 mmap(base, size,
2135 PROT_READ|PROT_WRITE|PROT_EXEC,
2136 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2137 }
2138 }
2139 ::close(fd);
2140 unlink(buf);
2141 }
2142 }
2144 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2145 int err) {
2146 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2147 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2148 strerror(err), err);
2149 }
2151 // NOTE: Bsd kernel does not really reserve the pages for us.
2152 // All it does is to check if there are enough free pages
2153 // left at the time of mmap(). This could be a potential
2154 // problem.
2155 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2156 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2157 #ifdef __OpenBSD__
2158 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2159 if (::mprotect(addr, size, prot) == 0) {
2160 return true;
2161 }
2162 #else
2163 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2164 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2165 if (res != (uintptr_t) MAP_FAILED) {
2166 return true;
2167 }
2168 #endif
2170 // Warn about any commit errors we see in non-product builds just
2171 // in case mmap() doesn't work as described on the man page.
2172 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2174 return false;
2175 }
2177 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2178 bool exec) {
2179 // alignment_hint is ignored on this OS
2180 return pd_commit_memory(addr, size, exec);
2181 }
2183 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2184 const char* mesg) {
2185 assert(mesg != NULL, "mesg must be specified");
2186 if (!pd_commit_memory(addr, size, exec)) {
2187 // add extra info in product mode for vm_exit_out_of_memory():
2188 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2189 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2190 }
2191 }
2193 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2194 size_t alignment_hint, bool exec,
2195 const char* mesg) {
2196 // alignment_hint is ignored on this OS
2197 pd_commit_memory_or_exit(addr, size, exec, mesg);
2198 }
2200 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2201 }
2203 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2204 ::madvise(addr, bytes, MADV_DONTNEED);
2205 }
2207 void os::numa_make_global(char *addr, size_t bytes) {
2208 }
2210 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2211 }
2213 bool os::numa_topology_changed() { return false; }
2215 size_t os::numa_get_groups_num() {
2216 return 1;
2217 }
2219 int os::numa_get_group_id() {
2220 return 0;
2221 }
2223 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2224 if (size > 0) {
2225 ids[0] = 0;
2226 return 1;
2227 }
2228 return 0;
2229 }
2231 bool os::get_page_info(char *start, page_info* info) {
2232 return false;
2233 }
2235 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2236 return end;
2237 }
2240 bool os::pd_uncommit_memory(char* addr, size_t size) {
2241 #ifdef __OpenBSD__
2242 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2243 return ::mprotect(addr, size, PROT_NONE) == 0;
2244 #else
2245 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2246 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2247 return res != (uintptr_t) MAP_FAILED;
2248 #endif
2249 }
2251 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2252 return os::commit_memory(addr, size, !ExecMem);
2253 }
2255 // If this is a growable mapping, remove the guard pages entirely by
2256 // munmap()ping them. If not, just call uncommit_memory().
2257 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2258 return os::uncommit_memory(addr, size);
2259 }
2261 static address _highest_vm_reserved_address = NULL;
2263 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2264 // at 'requested_addr'. If there are existing memory mappings at the same
2265 // location, however, they will be overwritten. If 'fixed' is false,
2266 // 'requested_addr' is only treated as a hint, the return value may or
2267 // may not start from the requested address. Unlike Bsd mmap(), this
2268 // function returns NULL to indicate failure.
2269 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2270 char * addr;
2271 int flags;
2273 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2274 if (fixed) {
2275 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2276 flags |= MAP_FIXED;
2277 }
2279 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2280 // touch an uncommitted page. Otherwise, the read/write might
2281 // succeed if we have enough swap space to back the physical page.
2282 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2283 flags, -1, 0);
2285 if (addr != MAP_FAILED) {
2286 // anon_mmap() should only get called during VM initialization,
2287 // don't need lock (actually we can skip locking even it can be called
2288 // from multiple threads, because _highest_vm_reserved_address is just a
2289 // hint about the upper limit of non-stack memory regions.)
2290 if ((address)addr + bytes > _highest_vm_reserved_address) {
2291 _highest_vm_reserved_address = (address)addr + bytes;
2292 }
2293 }
2295 return addr == MAP_FAILED ? NULL : addr;
2296 }
2298 // Don't update _highest_vm_reserved_address, because there might be memory
2299 // regions above addr + size. If so, releasing a memory region only creates
2300 // a hole in the address space, it doesn't help prevent heap-stack collision.
2301 //
2302 static int anon_munmap(char * addr, size_t size) {
2303 return ::munmap(addr, size) == 0;
2304 }
2306 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2307 size_t alignment_hint) {
2308 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2309 }
2311 bool os::pd_release_memory(char* addr, size_t size) {
2312 return anon_munmap(addr, size);
2313 }
2315 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2316 // Bsd wants the mprotect address argument to be page aligned.
2317 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2319 // According to SUSv3, mprotect() should only be used with mappings
2320 // established by mmap(), and mmap() always maps whole pages. Unaligned
2321 // 'addr' likely indicates problem in the VM (e.g. trying to change
2322 // protection of malloc'ed or statically allocated memory). Check the
2323 // caller if you hit this assert.
2324 assert(addr == bottom, "sanity check");
2326 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2327 return ::mprotect(bottom, size, prot) == 0;
2328 }
2330 // Set protections specified
2331 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2332 bool is_committed) {
2333 unsigned int p = 0;
2334 switch (prot) {
2335 case MEM_PROT_NONE: p = PROT_NONE; break;
2336 case MEM_PROT_READ: p = PROT_READ; break;
2337 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2338 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2339 default:
2340 ShouldNotReachHere();
2341 }
2342 // is_committed is unused.
2343 return bsd_mprotect(addr, bytes, p);
2344 }
2346 bool os::guard_memory(char* addr, size_t size) {
2347 return bsd_mprotect(addr, size, PROT_NONE);
2348 }
2350 bool os::unguard_memory(char* addr, size_t size) {
2351 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2352 }
2354 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2355 return false;
2356 }
2358 // Large page support
2360 static size_t _large_page_size = 0;
2362 void os::large_page_init() {
2363 }
2366 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2367 fatal("This code is not used or maintained.");
2369 // "exec" is passed in but not used. Creating the shared image for
2370 // the code cache doesn't have an SHM_X executable permission to check.
2371 assert(UseLargePages && UseSHM, "only for SHM large pages");
2373 key_t key = IPC_PRIVATE;
2374 char *addr;
2376 bool warn_on_failure = UseLargePages &&
2377 (!FLAG_IS_DEFAULT(UseLargePages) ||
2378 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2379 );
2380 char msg[128];
2382 // Create a large shared memory region to attach to based on size.
2383 // Currently, size is the total size of the heap
2384 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2385 if (shmid == -1) {
2386 // Possible reasons for shmget failure:
2387 // 1. shmmax is too small for Java heap.
2388 // > check shmmax value: cat /proc/sys/kernel/shmmax
2389 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2390 // 2. not enough large page memory.
2391 // > check available large pages: cat /proc/meminfo
2392 // > increase amount of large pages:
2393 // echo new_value > /proc/sys/vm/nr_hugepages
2394 // Note 1: different Bsd may use different name for this property,
2395 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2396 // Note 2: it's possible there's enough physical memory available but
2397 // they are so fragmented after a long run that they can't
2398 // coalesce into large pages. Try to reserve large pages when
2399 // the system is still "fresh".
2400 if (warn_on_failure) {
2401 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2402 warning(msg);
2403 }
2404 return NULL;
2405 }
2407 // attach to the region
2408 addr = (char*)shmat(shmid, req_addr, 0);
2409 int err = errno;
2411 // Remove shmid. If shmat() is successful, the actual shared memory segment
2412 // will be deleted when it's detached by shmdt() or when the process
2413 // terminates. If shmat() is not successful this will remove the shared
2414 // segment immediately.
2415 shmctl(shmid, IPC_RMID, NULL);
2417 if ((intptr_t)addr == -1) {
2418 if (warn_on_failure) {
2419 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2420 warning(msg);
2421 }
2422 return NULL;
2423 }
2425 // The memory is committed
2426 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2428 return addr;
2429 }
2431 bool os::release_memory_special(char* base, size_t bytes) {
2432 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2433 // detaching the SHM segment will also delete it, see reserve_memory_special()
2434 int rslt = shmdt(base);
2435 if (rslt == 0) {
2436 tkr.record((address)base, bytes);
2437 return true;
2438 } else {
2439 tkr.discard();
2440 return false;
2441 }
2443 }
2445 size_t os::large_page_size() {
2446 return _large_page_size;
2447 }
2449 // HugeTLBFS allows application to commit large page memory on demand;
2450 // with SysV SHM the entire memory region must be allocated as shared
2451 // memory.
2452 bool os::can_commit_large_page_memory() {
2453 return UseHugeTLBFS;
2454 }
2456 bool os::can_execute_large_page_memory() {
2457 return UseHugeTLBFS;
2458 }
2460 // Reserve memory at an arbitrary address, only if that area is
2461 // available (and not reserved for something else).
2463 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2464 const int max_tries = 10;
2465 char* base[max_tries];
2466 size_t size[max_tries];
2467 const size_t gap = 0x000000;
2469 // Assert only that the size is a multiple of the page size, since
2470 // that's all that mmap requires, and since that's all we really know
2471 // about at this low abstraction level. If we need higher alignment,
2472 // we can either pass an alignment to this method or verify alignment
2473 // in one of the methods further up the call chain. See bug 5044738.
2474 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2476 // Repeatedly allocate blocks until the block is allocated at the
2477 // right spot. Give up after max_tries. Note that reserve_memory() will
2478 // automatically update _highest_vm_reserved_address if the call is
2479 // successful. The variable tracks the highest memory address every reserved
2480 // by JVM. It is used to detect heap-stack collision if running with
2481 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2482 // space than needed, it could confuse the collision detecting code. To
2483 // solve the problem, save current _highest_vm_reserved_address and
2484 // calculate the correct value before return.
2485 address old_highest = _highest_vm_reserved_address;
2487 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2488 // if kernel honors the hint then we can return immediately.
2489 char * addr = anon_mmap(requested_addr, bytes, false);
2490 if (addr == requested_addr) {
2491 return requested_addr;
2492 }
2494 if (addr != NULL) {
2495 // mmap() is successful but it fails to reserve at the requested address
2496 anon_munmap(addr, bytes);
2497 }
2499 int i;
2500 for (i = 0; i < max_tries; ++i) {
2501 base[i] = reserve_memory(bytes);
2503 if (base[i] != NULL) {
2504 // Is this the block we wanted?
2505 if (base[i] == requested_addr) {
2506 size[i] = bytes;
2507 break;
2508 }
2510 // Does this overlap the block we wanted? Give back the overlapped
2511 // parts and try again.
2513 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2514 if (top_overlap >= 0 && top_overlap < bytes) {
2515 unmap_memory(base[i], top_overlap);
2516 base[i] += top_overlap;
2517 size[i] = bytes - top_overlap;
2518 } else {
2519 size_t bottom_overlap = base[i] + bytes - requested_addr;
2520 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2521 unmap_memory(requested_addr, bottom_overlap);
2522 size[i] = bytes - bottom_overlap;
2523 } else {
2524 size[i] = bytes;
2525 }
2526 }
2527 }
2528 }
2530 // Give back the unused reserved pieces.
2532 for (int j = 0; j < i; ++j) {
2533 if (base[j] != NULL) {
2534 unmap_memory(base[j], size[j]);
2535 }
2536 }
2538 if (i < max_tries) {
2539 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2540 return requested_addr;
2541 } else {
2542 _highest_vm_reserved_address = old_highest;
2543 return NULL;
2544 }
2545 }
2547 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2548 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2549 }
2551 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2552 // Solaris uses poll(), bsd uses park().
2553 // Poll() is likely a better choice, assuming that Thread.interrupt()
2554 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2555 // SIGSEGV, see 4355769.
2557 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2558 assert(thread == Thread::current(), "thread consistency check");
2560 ParkEvent * const slp = thread->_SleepEvent ;
2561 slp->reset() ;
2562 OrderAccess::fence() ;
2564 if (interruptible) {
2565 jlong prevtime = javaTimeNanos();
2567 for (;;) {
2568 if (os::is_interrupted(thread, true)) {
2569 return OS_INTRPT;
2570 }
2572 jlong newtime = javaTimeNanos();
2574 if (newtime - prevtime < 0) {
2575 // time moving backwards, should only happen if no monotonic clock
2576 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2577 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2578 } else {
2579 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2580 }
2582 if(millis <= 0) {
2583 return OS_OK;
2584 }
2586 prevtime = newtime;
2588 {
2589 assert(thread->is_Java_thread(), "sanity check");
2590 JavaThread *jt = (JavaThread *) thread;
2591 ThreadBlockInVM tbivm(jt);
2592 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2594 jt->set_suspend_equivalent();
2595 // cleared by handle_special_suspend_equivalent_condition() or
2596 // java_suspend_self() via check_and_wait_while_suspended()
2598 slp->park(millis);
2600 // were we externally suspended while we were waiting?
2601 jt->check_and_wait_while_suspended();
2602 }
2603 }
2604 } else {
2605 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2606 jlong prevtime = javaTimeNanos();
2608 for (;;) {
2609 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2610 // the 1st iteration ...
2611 jlong newtime = javaTimeNanos();
2613 if (newtime - prevtime < 0) {
2614 // time moving backwards, should only happen if no monotonic clock
2615 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2616 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2617 } else {
2618 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2619 }
2621 if(millis <= 0) break ;
2623 prevtime = newtime;
2624 slp->park(millis);
2625 }
2626 return OS_OK ;
2627 }
2628 }
2630 int os::naked_sleep() {
2631 // %% make the sleep time an integer flag. for now use 1 millisec.
2632 return os::sleep(Thread::current(), 1, false);
2633 }
2635 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2636 void os::infinite_sleep() {
2637 while (true) { // sleep forever ...
2638 ::sleep(100); // ... 100 seconds at a time
2639 }
2640 }
2642 // Used to convert frequent JVM_Yield() to nops
2643 bool os::dont_yield() {
2644 return DontYieldALot;
2645 }
2647 void os::yield() {
2648 sched_yield();
2649 }
2651 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2653 void os::yield_all(int attempts) {
2654 // Yields to all threads, including threads with lower priorities
2655 // Threads on Bsd are all with same priority. The Solaris style
2656 // os::yield_all() with nanosleep(1ms) is not necessary.
2657 sched_yield();
2658 }
2660 // Called from the tight loops to possibly influence time-sharing heuristics
2661 void os::loop_breaker(int attempts) {
2662 os::yield_all(attempts);
2663 }
2665 ////////////////////////////////////////////////////////////////////////////////
2666 // thread priority support
2668 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2669 // only supports dynamic priority, static priority must be zero. For real-time
2670 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2671 // However, for large multi-threaded applications, SCHED_RR is not only slower
2672 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2673 // of 5 runs - Sep 2005).
2674 //
2675 // The following code actually changes the niceness of kernel-thread/LWP. It
2676 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2677 // not the entire user process, and user level threads are 1:1 mapped to kernel
2678 // threads. It has always been the case, but could change in the future. For
2679 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2680 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2682 #if !defined(__APPLE__)
2683 int os::java_to_os_priority[CriticalPriority + 1] = {
2684 19, // 0 Entry should never be used
2686 0, // 1 MinPriority
2687 3, // 2
2688 6, // 3
2690 10, // 4
2691 15, // 5 NormPriority
2692 18, // 6
2694 21, // 7
2695 25, // 8
2696 28, // 9 NearMaxPriority
2698 31, // 10 MaxPriority
2700 31 // 11 CriticalPriority
2701 };
2702 #else
2703 /* Using Mach high-level priority assignments */
2704 int os::java_to_os_priority[CriticalPriority + 1] = {
2705 0, // 0 Entry should never be used (MINPRI_USER)
2707 27, // 1 MinPriority
2708 28, // 2
2709 29, // 3
2711 30, // 4
2712 31, // 5 NormPriority (BASEPRI_DEFAULT)
2713 32, // 6
2715 33, // 7
2716 34, // 8
2717 35, // 9 NearMaxPriority
2719 36, // 10 MaxPriority
2721 36 // 11 CriticalPriority
2722 };
2723 #endif
2725 static int prio_init() {
2726 if (ThreadPriorityPolicy == 1) {
2727 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2728 // if effective uid is not root. Perhaps, a more elegant way of doing
2729 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2730 if (geteuid() != 0) {
2731 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2732 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2733 }
2734 ThreadPriorityPolicy = 0;
2735 }
2736 }
2737 if (UseCriticalJavaThreadPriority) {
2738 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2739 }
2740 return 0;
2741 }
2743 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2744 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2746 #ifdef __OpenBSD__
2747 // OpenBSD pthread_setprio starves low priority threads
2748 return OS_OK;
2749 #elif defined(__FreeBSD__)
2750 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2751 #elif defined(__APPLE__) || defined(__NetBSD__)
2752 struct sched_param sp;
2753 int policy;
2754 pthread_t self = pthread_self();
2756 if (pthread_getschedparam(self, &policy, &sp) != 0)
2757 return OS_ERR;
2759 sp.sched_priority = newpri;
2760 if (pthread_setschedparam(self, policy, &sp) != 0)
2761 return OS_ERR;
2763 return OS_OK;
2764 #else
2765 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2766 return (ret == 0) ? OS_OK : OS_ERR;
2767 #endif
2768 }
2770 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2771 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2772 *priority_ptr = java_to_os_priority[NormPriority];
2773 return OS_OK;
2774 }
2776 errno = 0;
2777 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2778 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2779 #elif defined(__APPLE__) || defined(__NetBSD__)
2780 int policy;
2781 struct sched_param sp;
2783 pthread_getschedparam(pthread_self(), &policy, &sp);
2784 *priority_ptr = sp.sched_priority;
2785 #else
2786 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2787 #endif
2788 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2789 }
2791 // Hint to the underlying OS that a task switch would not be good.
2792 // Void return because it's a hint and can fail.
2793 void os::hint_no_preempt() {}
2795 ////////////////////////////////////////////////////////////////////////////////
2796 // suspend/resume support
2798 // the low-level signal-based suspend/resume support is a remnant from the
2799 // old VM-suspension that used to be for java-suspension, safepoints etc,
2800 // within hotspot. Now there is a single use-case for this:
2801 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2802 // that runs in the watcher thread.
2803 // The remaining code is greatly simplified from the more general suspension
2804 // code that used to be used.
2805 //
2806 // The protocol is quite simple:
2807 // - suspend:
2808 // - sends a signal to the target thread
2809 // - polls the suspend state of the osthread using a yield loop
2810 // - target thread signal handler (SR_handler) sets suspend state
2811 // and blocks in sigsuspend until continued
2812 // - resume:
2813 // - sets target osthread state to continue
2814 // - sends signal to end the sigsuspend loop in the SR_handler
2815 //
2816 // Note that the SR_lock plays no role in this suspend/resume protocol.
2817 //
2819 static void resume_clear_context(OSThread *osthread) {
2820 osthread->set_ucontext(NULL);
2821 osthread->set_siginfo(NULL);
2822 }
2824 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2825 osthread->set_ucontext(context);
2826 osthread->set_siginfo(siginfo);
2827 }
2829 //
2830 // Handler function invoked when a thread's execution is suspended or
2831 // resumed. We have to be careful that only async-safe functions are
2832 // called here (Note: most pthread functions are not async safe and
2833 // should be avoided.)
2834 //
2835 // Note: sigwait() is a more natural fit than sigsuspend() from an
2836 // interface point of view, but sigwait() prevents the signal hander
2837 // from being run. libpthread would get very confused by not having
2838 // its signal handlers run and prevents sigwait()'s use with the
2839 // mutex granting granting signal.
2840 //
2841 // Currently only ever called on the VMThread or JavaThread
2842 //
2843 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2844 // Save and restore errno to avoid confusing native code with EINTR
2845 // after sigsuspend.
2846 int old_errno = errno;
2848 Thread* thread = Thread::current();
2849 OSThread* osthread = thread->osthread();
2850 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2852 os::SuspendResume::State current = osthread->sr.state();
2853 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2854 suspend_save_context(osthread, siginfo, context);
2856 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2857 os::SuspendResume::State state = osthread->sr.suspended();
2858 if (state == os::SuspendResume::SR_SUSPENDED) {
2859 sigset_t suspend_set; // signals for sigsuspend()
2861 // get current set of blocked signals and unblock resume signal
2862 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2863 sigdelset(&suspend_set, SR_signum);
2865 sr_semaphore.signal();
2866 // wait here until we are resumed
2867 while (1) {
2868 sigsuspend(&suspend_set);
2870 os::SuspendResume::State result = osthread->sr.running();
2871 if (result == os::SuspendResume::SR_RUNNING) {
2872 sr_semaphore.signal();
2873 break;
2874 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2875 ShouldNotReachHere();
2876 }
2877 }
2879 } else if (state == os::SuspendResume::SR_RUNNING) {
2880 // request was cancelled, continue
2881 } else {
2882 ShouldNotReachHere();
2883 }
2885 resume_clear_context(osthread);
2886 } else if (current == os::SuspendResume::SR_RUNNING) {
2887 // request was cancelled, continue
2888 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2889 // ignore
2890 } else {
2891 // ignore
2892 }
2894 errno = old_errno;
2895 }
2898 static int SR_initialize() {
2899 struct sigaction act;
2900 char *s;
2901 /* Get signal number to use for suspend/resume */
2902 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2903 int sig = ::strtol(s, 0, 10);
2904 if (sig > 0 || sig < NSIG) {
2905 SR_signum = sig;
2906 }
2907 }
2909 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2910 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2912 sigemptyset(&SR_sigset);
2913 sigaddset(&SR_sigset, SR_signum);
2915 /* Set up signal handler for suspend/resume */
2916 act.sa_flags = SA_RESTART|SA_SIGINFO;
2917 act.sa_handler = (void (*)(int)) SR_handler;
2919 // SR_signum is blocked by default.
2920 // 4528190 - We also need to block pthread restart signal (32 on all
2921 // supported Bsd platforms). Note that BsdThreads need to block
2922 // this signal for all threads to work properly. So we don't have
2923 // to use hard-coded signal number when setting up the mask.
2924 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2926 if (sigaction(SR_signum, &act, 0) == -1) {
2927 return -1;
2928 }
2930 // Save signal flag
2931 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2932 return 0;
2933 }
2935 static int sr_notify(OSThread* osthread) {
2936 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2937 assert_status(status == 0, status, "pthread_kill");
2938 return status;
2939 }
2941 // "Randomly" selected value for how long we want to spin
2942 // before bailing out on suspending a thread, also how often
2943 // we send a signal to a thread we want to resume
2944 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2945 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2947 // returns true on success and false on error - really an error is fatal
2948 // but this seems the normal response to library errors
2949 static bool do_suspend(OSThread* osthread) {
2950 assert(osthread->sr.is_running(), "thread should be running");
2951 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2953 // mark as suspended and send signal
2954 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2955 // failed to switch, state wasn't running?
2956 ShouldNotReachHere();
2957 return false;
2958 }
2960 if (sr_notify(osthread) != 0) {
2961 ShouldNotReachHere();
2962 }
2964 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2965 while (true) {
2966 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2967 break;
2968 } else {
2969 // timeout
2970 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2971 if (cancelled == os::SuspendResume::SR_RUNNING) {
2972 return false;
2973 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2974 // make sure that we consume the signal on the semaphore as well
2975 sr_semaphore.wait();
2976 break;
2977 } else {
2978 ShouldNotReachHere();
2979 return false;
2980 }
2981 }
2982 }
2984 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2985 return true;
2986 }
2988 static void do_resume(OSThread* osthread) {
2989 assert(osthread->sr.is_suspended(), "thread should be suspended");
2990 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2992 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2993 // failed to switch to WAKEUP_REQUEST
2994 ShouldNotReachHere();
2995 return;
2996 }
2998 while (true) {
2999 if (sr_notify(osthread) == 0) {
3000 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3001 if (osthread->sr.is_running()) {
3002 return;
3003 }
3004 }
3005 } else {
3006 ShouldNotReachHere();
3007 }
3008 }
3010 guarantee(osthread->sr.is_running(), "Must be running!");
3011 }
3013 ////////////////////////////////////////////////////////////////////////////////
3014 // interrupt support
3016 void os::interrupt(Thread* thread) {
3017 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3018 "possibility of dangling Thread pointer");
3020 OSThread* osthread = thread->osthread();
3022 if (!osthread->interrupted()) {
3023 osthread->set_interrupted(true);
3024 // More than one thread can get here with the same value of osthread,
3025 // resulting in multiple notifications. We do, however, want the store
3026 // to interrupted() to be visible to other threads before we execute unpark().
3027 OrderAccess::fence();
3028 ParkEvent * const slp = thread->_SleepEvent ;
3029 if (slp != NULL) slp->unpark() ;
3030 }
3032 // For JSR166. Unpark even if interrupt status already was set
3033 if (thread->is_Java_thread())
3034 ((JavaThread*)thread)->parker()->unpark();
3036 ParkEvent * ev = thread->_ParkEvent ;
3037 if (ev != NULL) ev->unpark() ;
3039 }
3041 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3042 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3043 "possibility of dangling Thread pointer");
3045 OSThread* osthread = thread->osthread();
3047 bool interrupted = osthread->interrupted();
3049 if (interrupted && clear_interrupted) {
3050 osthread->set_interrupted(false);
3051 // consider thread->_SleepEvent->reset() ... optional optimization
3052 }
3054 return interrupted;
3055 }
3057 ///////////////////////////////////////////////////////////////////////////////////
3058 // signal handling (except suspend/resume)
3060 // This routine may be used by user applications as a "hook" to catch signals.
3061 // The user-defined signal handler must pass unrecognized signals to this
3062 // routine, and if it returns true (non-zero), then the signal handler must
3063 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3064 // routine will never retun false (zero), but instead will execute a VM panic
3065 // routine kill the process.
3066 //
3067 // If this routine returns false, it is OK to call it again. This allows
3068 // the user-defined signal handler to perform checks either before or after
3069 // the VM performs its own checks. Naturally, the user code would be making
3070 // a serious error if it tried to handle an exception (such as a null check
3071 // or breakpoint) that the VM was generating for its own correct operation.
3072 //
3073 // This routine may recognize any of the following kinds of signals:
3074 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3075 // It should be consulted by handlers for any of those signals.
3076 //
3077 // The caller of this routine must pass in the three arguments supplied
3078 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3079 // field of the structure passed to sigaction(). This routine assumes that
3080 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3081 //
3082 // Note that the VM will print warnings if it detects conflicting signal
3083 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3084 //
3085 extern "C" JNIEXPORT int
3086 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3087 void* ucontext, int abort_if_unrecognized);
3089 void signalHandler(int sig, siginfo_t* info, void* uc) {
3090 assert(info != NULL && uc != NULL, "it must be old kernel");
3091 int orig_errno = errno; // Preserve errno value over signal handler.
3092 JVM_handle_bsd_signal(sig, info, uc, true);
3093 errno = orig_errno;
3094 }
3097 // This boolean allows users to forward their own non-matching signals
3098 // to JVM_handle_bsd_signal, harmlessly.
3099 bool os::Bsd::signal_handlers_are_installed = false;
3101 // For signal-chaining
3102 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3103 unsigned int os::Bsd::sigs = 0;
3104 bool os::Bsd::libjsig_is_loaded = false;
3105 typedef struct sigaction *(*get_signal_t)(int);
3106 get_signal_t os::Bsd::get_signal_action = NULL;
3108 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3109 struct sigaction *actp = NULL;
3111 if (libjsig_is_loaded) {
3112 // Retrieve the old signal handler from libjsig
3113 actp = (*get_signal_action)(sig);
3114 }
3115 if (actp == NULL) {
3116 // Retrieve the preinstalled signal handler from jvm
3117 actp = get_preinstalled_handler(sig);
3118 }
3120 return actp;
3121 }
3123 static bool call_chained_handler(struct sigaction *actp, int sig,
3124 siginfo_t *siginfo, void *context) {
3125 // Call the old signal handler
3126 if (actp->sa_handler == SIG_DFL) {
3127 // It's more reasonable to let jvm treat it as an unexpected exception
3128 // instead of taking the default action.
3129 return false;
3130 } else if (actp->sa_handler != SIG_IGN) {
3131 if ((actp->sa_flags & SA_NODEFER) == 0) {
3132 // automaticlly block the signal
3133 sigaddset(&(actp->sa_mask), sig);
3134 }
3136 sa_handler_t hand;
3137 sa_sigaction_t sa;
3138 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3139 // retrieve the chained handler
3140 if (siginfo_flag_set) {
3141 sa = actp->sa_sigaction;
3142 } else {
3143 hand = actp->sa_handler;
3144 }
3146 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3147 actp->sa_handler = SIG_DFL;
3148 }
3150 // try to honor the signal mask
3151 sigset_t oset;
3152 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3154 // call into the chained handler
3155 if (siginfo_flag_set) {
3156 (*sa)(sig, siginfo, context);
3157 } else {
3158 (*hand)(sig);
3159 }
3161 // restore the signal mask
3162 pthread_sigmask(SIG_SETMASK, &oset, 0);
3163 }
3164 // Tell jvm's signal handler the signal is taken care of.
3165 return true;
3166 }
3168 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3169 bool chained = false;
3170 // signal-chaining
3171 if (UseSignalChaining) {
3172 struct sigaction *actp = get_chained_signal_action(sig);
3173 if (actp != NULL) {
3174 chained = call_chained_handler(actp, sig, siginfo, context);
3175 }
3176 }
3177 return chained;
3178 }
3180 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3181 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3182 return &sigact[sig];
3183 }
3184 return NULL;
3185 }
3187 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3188 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3189 sigact[sig] = oldAct;
3190 sigs |= (unsigned int)1 << sig;
3191 }
3193 // for diagnostic
3194 int os::Bsd::sigflags[MAXSIGNUM];
3196 int os::Bsd::get_our_sigflags(int sig) {
3197 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3198 return sigflags[sig];
3199 }
3201 void os::Bsd::set_our_sigflags(int sig, int flags) {
3202 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3203 sigflags[sig] = flags;
3204 }
3206 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3207 // Check for overwrite.
3208 struct sigaction oldAct;
3209 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3211 void* oldhand = oldAct.sa_sigaction
3212 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3213 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3214 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3215 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3216 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3217 if (AllowUserSignalHandlers || !set_installed) {
3218 // Do not overwrite; user takes responsibility to forward to us.
3219 return;
3220 } else if (UseSignalChaining) {
3221 // save the old handler in jvm
3222 save_preinstalled_handler(sig, oldAct);
3223 // libjsig also interposes the sigaction() call below and saves the
3224 // old sigaction on it own.
3225 } else {
3226 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3227 "%#lx for signal %d.", (long)oldhand, sig));
3228 }
3229 }
3231 struct sigaction sigAct;
3232 sigfillset(&(sigAct.sa_mask));
3233 sigAct.sa_handler = SIG_DFL;
3234 if (!set_installed) {
3235 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3236 } else {
3237 sigAct.sa_sigaction = signalHandler;
3238 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3239 }
3240 #if __APPLE__
3241 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3242 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3243 // if the signal handler declares it will handle it on alternate stack.
3244 // Notice we only declare we will handle it on alt stack, but we are not
3245 // actually going to use real alt stack - this is just a workaround.
3246 // Please see ux_exception.c, method catch_mach_exception_raise for details
3247 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3248 if (sig == SIGSEGV) {
3249 sigAct.sa_flags |= SA_ONSTACK;
3250 }
3251 #endif
3253 // Save flags, which are set by ours
3254 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3255 sigflags[sig] = sigAct.sa_flags;
3257 int ret = sigaction(sig, &sigAct, &oldAct);
3258 assert(ret == 0, "check");
3260 void* oldhand2 = oldAct.sa_sigaction
3261 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3262 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3263 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3264 }
3266 // install signal handlers for signals that HotSpot needs to
3267 // handle in order to support Java-level exception handling.
3269 void os::Bsd::install_signal_handlers() {
3270 if (!signal_handlers_are_installed) {
3271 signal_handlers_are_installed = true;
3273 // signal-chaining
3274 typedef void (*signal_setting_t)();
3275 signal_setting_t begin_signal_setting = NULL;
3276 signal_setting_t end_signal_setting = NULL;
3277 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3278 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3279 if (begin_signal_setting != NULL) {
3280 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3281 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3282 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3283 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3284 libjsig_is_loaded = true;
3285 assert(UseSignalChaining, "should enable signal-chaining");
3286 }
3287 if (libjsig_is_loaded) {
3288 // Tell libjsig jvm is setting signal handlers
3289 (*begin_signal_setting)();
3290 }
3292 set_signal_handler(SIGSEGV, true);
3293 set_signal_handler(SIGPIPE, true);
3294 set_signal_handler(SIGBUS, true);
3295 set_signal_handler(SIGILL, true);
3296 set_signal_handler(SIGFPE, true);
3297 set_signal_handler(SIGXFSZ, true);
3299 #if defined(__APPLE__)
3300 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3301 // signals caught and handled by the JVM. To work around this, we reset the mach task
3302 // signal handler that's placed on our process by CrashReporter. This disables
3303 // CrashReporter-based reporting.
3304 //
3305 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3306 // on caught fatal signals.
3307 //
3308 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3309 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3310 // exception handling, while leaving the standard BSD signal handlers functional.
3311 kern_return_t kr;
3312 kr = task_set_exception_ports(mach_task_self(),
3313 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3314 MACH_PORT_NULL,
3315 EXCEPTION_STATE_IDENTITY,
3316 MACHINE_THREAD_STATE);
3318 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3319 #endif
3321 if (libjsig_is_loaded) {
3322 // Tell libjsig jvm finishes setting signal handlers
3323 (*end_signal_setting)();
3324 }
3326 // We don't activate signal checker if libjsig is in place, we trust ourselves
3327 // and if UserSignalHandler is installed all bets are off
3328 if (CheckJNICalls) {
3329 if (libjsig_is_loaded) {
3330 if (PrintJNIResolving) {
3331 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3332 }
3333 check_signals = false;
3334 }
3335 if (AllowUserSignalHandlers) {
3336 if (PrintJNIResolving) {
3337 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3338 }
3339 check_signals = false;
3340 }
3341 }
3342 }
3343 }
3346 /////
3347 // glibc on Bsd platform uses non-documented flag
3348 // to indicate, that some special sort of signal
3349 // trampoline is used.
3350 // We will never set this flag, and we should
3351 // ignore this flag in our diagnostic
3352 #ifdef SIGNIFICANT_SIGNAL_MASK
3353 #undef SIGNIFICANT_SIGNAL_MASK
3354 #endif
3355 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3357 static const char* get_signal_handler_name(address handler,
3358 char* buf, int buflen) {
3359 int offset;
3360 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3361 if (found) {
3362 // skip directory names
3363 const char *p1, *p2;
3364 p1 = buf;
3365 size_t len = strlen(os::file_separator());
3366 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3367 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3368 } else {
3369 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3370 }
3371 return buf;
3372 }
3374 static void print_signal_handler(outputStream* st, int sig,
3375 char* buf, size_t buflen) {
3376 struct sigaction sa;
3378 sigaction(sig, NULL, &sa);
3380 // See comment for SIGNIFICANT_SIGNAL_MASK define
3381 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3383 st->print("%s: ", os::exception_name(sig, buf, buflen));
3385 address handler = (sa.sa_flags & SA_SIGINFO)
3386 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3387 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3389 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3390 st->print("SIG_DFL");
3391 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3392 st->print("SIG_IGN");
3393 } else {
3394 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3395 }
3397 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3399 address rh = VMError::get_resetted_sighandler(sig);
3400 // May be, handler was resetted by VMError?
3401 if(rh != NULL) {
3402 handler = rh;
3403 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3404 }
3406 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3408 // Check: is it our handler?
3409 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3410 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3411 // It is our signal handler
3412 // check for flags, reset system-used one!
3413 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3414 st->print(
3415 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3416 os::Bsd::get_our_sigflags(sig));
3417 }
3418 }
3419 st->cr();
3420 }
3423 #define DO_SIGNAL_CHECK(sig) \
3424 if (!sigismember(&check_signal_done, sig)) \
3425 os::Bsd::check_signal_handler(sig)
3427 // This method is a periodic task to check for misbehaving JNI applications
3428 // under CheckJNI, we can add any periodic checks here
3430 void os::run_periodic_checks() {
3432 if (check_signals == false) return;
3434 // SEGV and BUS if overridden could potentially prevent
3435 // generation of hs*.log in the event of a crash, debugging
3436 // such a case can be very challenging, so we absolutely
3437 // check the following for a good measure:
3438 DO_SIGNAL_CHECK(SIGSEGV);
3439 DO_SIGNAL_CHECK(SIGILL);
3440 DO_SIGNAL_CHECK(SIGFPE);
3441 DO_SIGNAL_CHECK(SIGBUS);
3442 DO_SIGNAL_CHECK(SIGPIPE);
3443 DO_SIGNAL_CHECK(SIGXFSZ);
3446 // ReduceSignalUsage allows the user to override these handlers
3447 // see comments at the very top and jvm_solaris.h
3448 if (!ReduceSignalUsage) {
3449 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3450 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3451 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3452 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3453 }
3455 DO_SIGNAL_CHECK(SR_signum);
3456 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3457 }
3459 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3461 static os_sigaction_t os_sigaction = NULL;
3463 void os::Bsd::check_signal_handler(int sig) {
3464 char buf[O_BUFLEN];
3465 address jvmHandler = NULL;
3468 struct sigaction act;
3469 if (os_sigaction == NULL) {
3470 // only trust the default sigaction, in case it has been interposed
3471 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3472 if (os_sigaction == NULL) return;
3473 }
3475 os_sigaction(sig, (struct sigaction*)NULL, &act);
3478 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3480 address thisHandler = (act.sa_flags & SA_SIGINFO)
3481 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3482 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3485 switch(sig) {
3486 case SIGSEGV:
3487 case SIGBUS:
3488 case SIGFPE:
3489 case SIGPIPE:
3490 case SIGILL:
3491 case SIGXFSZ:
3492 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3493 break;
3495 case SHUTDOWN1_SIGNAL:
3496 case SHUTDOWN2_SIGNAL:
3497 case SHUTDOWN3_SIGNAL:
3498 case BREAK_SIGNAL:
3499 jvmHandler = (address)user_handler();
3500 break;
3502 case INTERRUPT_SIGNAL:
3503 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3504 break;
3506 default:
3507 if (sig == SR_signum) {
3508 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3509 } else {
3510 return;
3511 }
3512 break;
3513 }
3515 if (thisHandler != jvmHandler) {
3516 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3517 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3518 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3519 // No need to check this sig any longer
3520 sigaddset(&check_signal_done, sig);
3521 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3522 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3523 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3524 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3525 // No need to check this sig any longer
3526 sigaddset(&check_signal_done, sig);
3527 }
3529 // Dump all the signal
3530 if (sigismember(&check_signal_done, sig)) {
3531 print_signal_handlers(tty, buf, O_BUFLEN);
3532 }
3533 }
3535 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3537 extern bool signal_name(int signo, char* buf, size_t len);
3539 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3540 if (0 < exception_code && exception_code <= SIGRTMAX) {
3541 // signal
3542 if (!signal_name(exception_code, buf, size)) {
3543 jio_snprintf(buf, size, "SIG%d", exception_code);
3544 }
3545 return buf;
3546 } else {
3547 return NULL;
3548 }
3549 }
3551 // this is called _before_ the most of global arguments have been parsed
3552 void os::init(void) {
3553 char dummy; /* used to get a guess on initial stack address */
3554 // first_hrtime = gethrtime();
3556 // With BsdThreads the JavaMain thread pid (primordial thread)
3557 // is different than the pid of the java launcher thread.
3558 // So, on Bsd, the launcher thread pid is passed to the VM
3559 // via the sun.java.launcher.pid property.
3560 // Use this property instead of getpid() if it was correctly passed.
3561 // See bug 6351349.
3562 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3564 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3566 clock_tics_per_sec = CLK_TCK;
3568 init_random(1234567);
3570 ThreadCritical::initialize();
3572 Bsd::set_page_size(getpagesize());
3573 if (Bsd::page_size() == -1) {
3574 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3575 strerror(errno)));
3576 }
3577 init_page_sizes((size_t) Bsd::page_size());
3579 Bsd::initialize_system_info();
3581 // main_thread points to the aboriginal thread
3582 Bsd::_main_thread = pthread_self();
3584 Bsd::clock_init();
3585 initial_time_count = os::elapsed_counter();
3587 #ifdef __APPLE__
3588 // XXXDARWIN
3589 // Work around the unaligned VM callbacks in hotspot's
3590 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3591 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3592 // alignment when doing symbol lookup. To work around this, we force early
3593 // binding of all symbols now, thus binding when alignment is known-good.
3594 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3595 #endif
3596 }
3598 // To install functions for atexit system call
3599 extern "C" {
3600 static void perfMemory_exit_helper() {
3601 perfMemory_exit();
3602 }
3603 }
3605 // this is called _after_ the global arguments have been parsed
3606 jint os::init_2(void)
3607 {
3608 // Allocate a single page and mark it as readable for safepoint polling
3609 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3610 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3612 os::set_polling_page( polling_page );
3614 #ifndef PRODUCT
3615 if(Verbose && PrintMiscellaneous)
3616 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3617 #endif
3619 if (!UseMembar) {
3620 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3621 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3622 os::set_memory_serialize_page( mem_serialize_page );
3624 #ifndef PRODUCT
3625 if(Verbose && PrintMiscellaneous)
3626 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3627 #endif
3628 }
3630 // initialize suspend/resume support - must do this before signal_sets_init()
3631 if (SR_initialize() != 0) {
3632 perror("SR_initialize failed");
3633 return JNI_ERR;
3634 }
3636 Bsd::signal_sets_init();
3637 Bsd::install_signal_handlers();
3639 // Check minimum allowable stack size for thread creation and to initialize
3640 // the java system classes, including StackOverflowError - depends on page
3641 // size. Add a page for compiler2 recursion in main thread.
3642 // Add in 2*BytesPerWord times page size to account for VM stack during
3643 // class initialization depending on 32 or 64 bit VM.
3644 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3645 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3646 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3648 size_t threadStackSizeInBytes = ThreadStackSize * K;
3649 if (threadStackSizeInBytes != 0 &&
3650 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3651 tty->print_cr("\nThe stack size specified is too small, "
3652 "Specify at least %dk",
3653 os::Bsd::min_stack_allowed/ K);
3654 return JNI_ERR;
3655 }
3657 // Make the stack size a multiple of the page size so that
3658 // the yellow/red zones can be guarded.
3659 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3660 vm_page_size()));
3662 if (MaxFDLimit) {
3663 // set the number of file descriptors to max. print out error
3664 // if getrlimit/setrlimit fails but continue regardless.
3665 struct rlimit nbr_files;
3666 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3667 if (status != 0) {
3668 if (PrintMiscellaneous && (Verbose || WizardMode))
3669 perror("os::init_2 getrlimit failed");
3670 } else {
3671 nbr_files.rlim_cur = nbr_files.rlim_max;
3673 #ifdef __APPLE__
3674 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3675 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3676 // be used instead
3677 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3678 #endif
3680 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3681 if (status != 0) {
3682 if (PrintMiscellaneous && (Verbose || WizardMode))
3683 perror("os::init_2 setrlimit failed");
3684 }
3685 }
3686 }
3688 // at-exit methods are called in the reverse order of their registration.
3689 // atexit functions are called on return from main or as a result of a
3690 // call to exit(3C). There can be only 32 of these functions registered
3691 // and atexit() does not set errno.
3693 if (PerfAllowAtExitRegistration) {
3694 // only register atexit functions if PerfAllowAtExitRegistration is set.
3695 // atexit functions can be delayed until process exit time, which
3696 // can be problematic for embedded VM situations. Embedded VMs should
3697 // call DestroyJavaVM() to assure that VM resources are released.
3699 // note: perfMemory_exit_helper atexit function may be removed in
3700 // the future if the appropriate cleanup code can be added to the
3701 // VM_Exit VMOperation's doit method.
3702 if (atexit(perfMemory_exit_helper) != 0) {
3703 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3704 }
3705 }
3707 // initialize thread priority policy
3708 prio_init();
3710 #ifdef __APPLE__
3711 // dynamically link to objective c gc registration
3712 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3713 if (handleLibObjc != NULL) {
3714 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3715 }
3716 #endif
3718 return JNI_OK;
3719 }
3721 // this is called at the end of vm_initialization
3722 void os::init_3(void) { }
3724 // Mark the polling page as unreadable
3725 void os::make_polling_page_unreadable(void) {
3726 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3727 fatal("Could not disable polling page");
3728 };
3730 // Mark the polling page as readable
3731 void os::make_polling_page_readable(void) {
3732 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3733 fatal("Could not enable polling page");
3734 }
3735 };
3737 int os::active_processor_count() {
3738 return _processor_count;
3739 }
3741 void os::set_native_thread_name(const char *name) {
3742 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3743 // This is only supported in Snow Leopard and beyond
3744 if (name != NULL) {
3745 // Add a "Java: " prefix to the name
3746 char buf[MAXTHREADNAMESIZE];
3747 snprintf(buf, sizeof(buf), "Java: %s", name);
3748 pthread_setname_np(buf);
3749 }
3750 #endif
3751 }
3753 bool os::distribute_processes(uint length, uint* distribution) {
3754 // Not yet implemented.
3755 return false;
3756 }
3758 bool os::bind_to_processor(uint processor_id) {
3759 // Not yet implemented.
3760 return false;
3761 }
3763 void os::SuspendedThreadTask::internal_do_task() {
3764 if (do_suspend(_thread->osthread())) {
3765 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3766 do_task(context);
3767 do_resume(_thread->osthread());
3768 }
3769 }
3771 ///
3772 class PcFetcher : public os::SuspendedThreadTask {
3773 public:
3774 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3775 ExtendedPC result();
3776 protected:
3777 void do_task(const os::SuspendedThreadTaskContext& context);
3778 private:
3779 ExtendedPC _epc;
3780 };
3782 ExtendedPC PcFetcher::result() {
3783 guarantee(is_done(), "task is not done yet.");
3784 return _epc;
3785 }
3787 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3788 Thread* thread = context.thread();
3789 OSThread* osthread = thread->osthread();
3790 if (osthread->ucontext() != NULL) {
3791 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3792 } else {
3793 // NULL context is unexpected, double-check this is the VMThread
3794 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3795 }
3796 }
3798 // Suspends the target using the signal mechanism and then grabs the PC before
3799 // resuming the target. Used by the flat-profiler only
3800 ExtendedPC os::get_thread_pc(Thread* thread) {
3801 // Make sure that it is called by the watcher for the VMThread
3802 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3803 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3805 PcFetcher fetcher(thread);
3806 fetcher.run();
3807 return fetcher.result();
3808 }
3810 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3811 {
3812 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3813 }
3815 ////////////////////////////////////////////////////////////////////////////////
3816 // debug support
3818 bool os::find(address addr, outputStream* st) {
3819 Dl_info dlinfo;
3820 memset(&dlinfo, 0, sizeof(dlinfo));
3821 if (dladdr(addr, &dlinfo) != 0) {
3822 st->print(PTR_FORMAT ": ", addr);
3823 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3824 st->print("%s+%#x", dlinfo.dli_sname,
3825 addr - (intptr_t)dlinfo.dli_saddr);
3826 } else if (dlinfo.dli_fbase != NULL) {
3827 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3828 } else {
3829 st->print("<absolute address>");
3830 }
3831 if (dlinfo.dli_fname != NULL) {
3832 st->print(" in %s", dlinfo.dli_fname);
3833 }
3834 if (dlinfo.dli_fbase != NULL) {
3835 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3836 }
3837 st->cr();
3839 if (Verbose) {
3840 // decode some bytes around the PC
3841 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3842 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3843 address lowest = (address) dlinfo.dli_sname;
3844 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3845 if (begin < lowest) begin = lowest;
3846 Dl_info dlinfo2;
3847 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3848 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3849 end = (address) dlinfo2.dli_saddr;
3850 Disassembler::decode(begin, end, st);
3851 }
3852 return true;
3853 }
3854 return false;
3855 }
3857 ////////////////////////////////////////////////////////////////////////////////
3858 // misc
3860 // This does not do anything on Bsd. This is basically a hook for being
3861 // able to use structured exception handling (thread-local exception filters)
3862 // on, e.g., Win32.
3863 void
3864 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3865 JavaCallArguments* args, Thread* thread) {
3866 f(value, method, args, thread);
3867 }
3869 void os::print_statistics() {
3870 }
3872 int os::message_box(const char* title, const char* message) {
3873 int i;
3874 fdStream err(defaultStream::error_fd());
3875 for (i = 0; i < 78; i++) err.print_raw("=");
3876 err.cr();
3877 err.print_raw_cr(title);
3878 for (i = 0; i < 78; i++) err.print_raw("-");
3879 err.cr();
3880 err.print_raw_cr(message);
3881 for (i = 0; i < 78; i++) err.print_raw("=");
3882 err.cr();
3884 char buf[16];
3885 // Prevent process from exiting upon "read error" without consuming all CPU
3886 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3888 return buf[0] == 'y' || buf[0] == 'Y';
3889 }
3891 int os::stat(const char *path, struct stat *sbuf) {
3892 char pathbuf[MAX_PATH];
3893 if (strlen(path) > MAX_PATH - 1) {
3894 errno = ENAMETOOLONG;
3895 return -1;
3896 }
3897 os::native_path(strcpy(pathbuf, path));
3898 return ::stat(pathbuf, sbuf);
3899 }
3901 bool os::check_heap(bool force) {
3902 return true;
3903 }
3905 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3906 return ::vsnprintf(buf, count, format, args);
3907 }
3909 // Is a (classpath) directory empty?
3910 bool os::dir_is_empty(const char* path) {
3911 DIR *dir = NULL;
3912 struct dirent *ptr;
3914 dir = opendir(path);
3915 if (dir == NULL) return true;
3917 /* Scan the directory */
3918 bool result = true;
3919 char buf[sizeof(struct dirent) + MAX_PATH];
3920 while (result && (ptr = ::readdir(dir)) != NULL) {
3921 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3922 result = false;
3923 }
3924 }
3925 closedir(dir);
3926 return result;
3927 }
3929 // This code originates from JDK's sysOpen and open64_w
3930 // from src/solaris/hpi/src/system_md.c
3932 #ifndef O_DELETE
3933 #define O_DELETE 0x10000
3934 #endif
3936 // Open a file. Unlink the file immediately after open returns
3937 // if the specified oflag has the O_DELETE flag set.
3938 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3940 int os::open(const char *path, int oflag, int mode) {
3942 if (strlen(path) > MAX_PATH - 1) {
3943 errno = ENAMETOOLONG;
3944 return -1;
3945 }
3946 int fd;
3947 int o_delete = (oflag & O_DELETE);
3948 oflag = oflag & ~O_DELETE;
3950 fd = ::open(path, oflag, mode);
3951 if (fd == -1) return -1;
3953 //If the open succeeded, the file might still be a directory
3954 {
3955 struct stat buf;
3956 int ret = ::fstat(fd, &buf);
3957 int st_mode = buf.st_mode;
3959 if (ret != -1) {
3960 if ((st_mode & S_IFMT) == S_IFDIR) {
3961 errno = EISDIR;
3962 ::close(fd);
3963 return -1;
3964 }
3965 } else {
3966 ::close(fd);
3967 return -1;
3968 }
3969 }
3971 /*
3972 * All file descriptors that are opened in the JVM and not
3973 * specifically destined for a subprocess should have the
3974 * close-on-exec flag set. If we don't set it, then careless 3rd
3975 * party native code might fork and exec without closing all
3976 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3977 * UNIXProcess.c), and this in turn might:
3978 *
3979 * - cause end-of-file to fail to be detected on some file
3980 * descriptors, resulting in mysterious hangs, or
3981 *
3982 * - might cause an fopen in the subprocess to fail on a system
3983 * suffering from bug 1085341.
3984 *
3985 * (Yes, the default setting of the close-on-exec flag is a Unix
3986 * design flaw)
3987 *
3988 * See:
3989 * 1085341: 32-bit stdio routines should support file descriptors >255
3990 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3991 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3992 */
3993 #ifdef FD_CLOEXEC
3994 {
3995 int flags = ::fcntl(fd, F_GETFD);
3996 if (flags != -1)
3997 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3998 }
3999 #endif
4001 if (o_delete != 0) {
4002 ::unlink(path);
4003 }
4004 return fd;
4005 }
4008 // create binary file, rewriting existing file if required
4009 int os::create_binary_file(const char* path, bool rewrite_existing) {
4010 int oflags = O_WRONLY | O_CREAT;
4011 if (!rewrite_existing) {
4012 oflags |= O_EXCL;
4013 }
4014 return ::open(path, oflags, S_IREAD | S_IWRITE);
4015 }
4017 // return current position of file pointer
4018 jlong os::current_file_offset(int fd) {
4019 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4020 }
4022 // move file pointer to the specified offset
4023 jlong os::seek_to_file_offset(int fd, jlong offset) {
4024 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4025 }
4027 // This code originates from JDK's sysAvailable
4028 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4030 int os::available(int fd, jlong *bytes) {
4031 jlong cur, end;
4032 int mode;
4033 struct stat buf;
4035 if (::fstat(fd, &buf) >= 0) {
4036 mode = buf.st_mode;
4037 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4038 /*
4039 * XXX: is the following call interruptible? If so, this might
4040 * need to go through the INTERRUPT_IO() wrapper as for other
4041 * blocking, interruptible calls in this file.
4042 */
4043 int n;
4044 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4045 *bytes = n;
4046 return 1;
4047 }
4048 }
4049 }
4050 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4051 return 0;
4052 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4053 return 0;
4054 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4055 return 0;
4056 }
4057 *bytes = end - cur;
4058 return 1;
4059 }
4061 int os::socket_available(int fd, jint *pbytes) {
4062 if (fd < 0)
4063 return OS_OK;
4065 int ret;
4067 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4069 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4070 // is expected to return 0 on failure and 1 on success to the jdk.
4072 return (ret == OS_ERR) ? 0 : 1;
4073 }
4075 // Map a block of memory.
4076 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4077 char *addr, size_t bytes, bool read_only,
4078 bool allow_exec) {
4079 int prot;
4080 int flags;
4082 if (read_only) {
4083 prot = PROT_READ;
4084 flags = MAP_SHARED;
4085 } else {
4086 prot = PROT_READ | PROT_WRITE;
4087 flags = MAP_PRIVATE;
4088 }
4090 if (allow_exec) {
4091 prot |= PROT_EXEC;
4092 }
4094 if (addr != NULL) {
4095 flags |= MAP_FIXED;
4096 }
4098 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4099 fd, file_offset);
4100 if (mapped_address == MAP_FAILED) {
4101 return NULL;
4102 }
4103 return mapped_address;
4104 }
4107 // Remap a block of memory.
4108 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4109 char *addr, size_t bytes, bool read_only,
4110 bool allow_exec) {
4111 // same as map_memory() on this OS
4112 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4113 allow_exec);
4114 }
4117 // Unmap a block of memory.
4118 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4119 return munmap(addr, bytes) == 0;
4120 }
4122 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4123 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4124 // of a thread.
4125 //
4126 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4127 // the fast estimate available on the platform.
4129 jlong os::current_thread_cpu_time() {
4130 #ifdef __APPLE__
4131 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4132 #else
4133 Unimplemented();
4134 return 0;
4135 #endif
4136 }
4138 jlong os::thread_cpu_time(Thread* thread) {
4139 #ifdef __APPLE__
4140 return os::thread_cpu_time(thread, true /* user + sys */);
4141 #else
4142 Unimplemented();
4143 return 0;
4144 #endif
4145 }
4147 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4148 #ifdef __APPLE__
4149 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4150 #else
4151 Unimplemented();
4152 return 0;
4153 #endif
4154 }
4156 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4157 #ifdef __APPLE__
4158 struct thread_basic_info tinfo;
4159 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4160 kern_return_t kr;
4161 thread_t mach_thread;
4163 mach_thread = thread->osthread()->thread_id();
4164 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4165 if (kr != KERN_SUCCESS)
4166 return -1;
4168 if (user_sys_cpu_time) {
4169 jlong nanos;
4170 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4171 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4172 return nanos;
4173 } else {
4174 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4175 }
4176 #else
4177 Unimplemented();
4178 return 0;
4179 #endif
4180 }
4183 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4184 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4185 info_ptr->may_skip_backward = false; // elapsed time not wall time
4186 info_ptr->may_skip_forward = false; // elapsed time not wall time
4187 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4188 }
4190 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4191 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4192 info_ptr->may_skip_backward = false; // elapsed time not wall time
4193 info_ptr->may_skip_forward = false; // elapsed time not wall time
4194 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4195 }
4197 bool os::is_thread_cpu_time_supported() {
4198 #ifdef __APPLE__
4199 return true;
4200 #else
4201 return false;
4202 #endif
4203 }
4205 // System loadavg support. Returns -1 if load average cannot be obtained.
4206 // Bsd doesn't yet have a (official) notion of processor sets,
4207 // so just return the system wide load average.
4208 int os::loadavg(double loadavg[], int nelem) {
4209 return ::getloadavg(loadavg, nelem);
4210 }
4212 void os::pause() {
4213 char filename[MAX_PATH];
4214 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4215 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4216 } else {
4217 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4218 }
4220 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4221 if (fd != -1) {
4222 struct stat buf;
4223 ::close(fd);
4224 while (::stat(filename, &buf) == 0) {
4225 (void)::poll(NULL, 0, 100);
4226 }
4227 } else {
4228 jio_fprintf(stderr,
4229 "Could not open pause file '%s', continuing immediately.\n", filename);
4230 }
4231 }
4234 // Refer to the comments in os_solaris.cpp park-unpark.
4235 //
4236 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4237 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4238 // For specifics regarding the bug see GLIBC BUGID 261237 :
4239 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4240 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4241 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4242 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4243 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4244 // and monitorenter when we're using 1-0 locking. All those operations may result in
4245 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4246 // of libpthread avoids the problem, but isn't practical.
4247 //
4248 // Possible remedies:
4249 //
4250 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4251 // This is palliative and probabilistic, however. If the thread is preempted
4252 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4253 // than the minimum period may have passed, and the abstime may be stale (in the
4254 // past) resultin in a hang. Using this technique reduces the odds of a hang
4255 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4256 //
4257 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4258 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4259 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4260 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4261 // thread.
4262 //
4263 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4264 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4265 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4266 // This also works well. In fact it avoids kernel-level scalability impediments
4267 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4268 // timers in a graceful fashion.
4269 //
4270 // 4. When the abstime value is in the past it appears that control returns
4271 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4272 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4273 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4274 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4275 // It may be possible to avoid reinitialization by checking the return
4276 // value from pthread_cond_timedwait(). In addition to reinitializing the
4277 // condvar we must establish the invariant that cond_signal() is only called
4278 // within critical sections protected by the adjunct mutex. This prevents
4279 // cond_signal() from "seeing" a condvar that's in the midst of being
4280 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4281 // desirable signal-after-unlock optimization that avoids futile context switching.
4282 //
4283 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4284 // structure when a condvar is used or initialized. cond_destroy() would
4285 // release the helper structure. Our reinitialize-after-timedwait fix
4286 // put excessive stress on malloc/free and locks protecting the c-heap.
4287 //
4288 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4289 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4290 // and only enabling the work-around for vulnerable environments.
4292 // utility to compute the abstime argument to timedwait:
4293 // millis is the relative timeout time
4294 // abstime will be the absolute timeout time
4295 // TODO: replace compute_abstime() with unpackTime()
4297 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4298 if (millis < 0) millis = 0;
4299 struct timeval now;
4300 int status = gettimeofday(&now, NULL);
4301 assert(status == 0, "gettimeofday");
4302 jlong seconds = millis / 1000;
4303 millis %= 1000;
4304 if (seconds > 50000000) { // see man cond_timedwait(3T)
4305 seconds = 50000000;
4306 }
4307 abstime->tv_sec = now.tv_sec + seconds;
4308 long usec = now.tv_usec + millis * 1000;
4309 if (usec >= 1000000) {
4310 abstime->tv_sec += 1;
4311 usec -= 1000000;
4312 }
4313 abstime->tv_nsec = usec * 1000;
4314 return abstime;
4315 }
4318 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4319 // Conceptually TryPark() should be equivalent to park(0).
4321 int os::PlatformEvent::TryPark() {
4322 for (;;) {
4323 const int v = _Event ;
4324 guarantee ((v == 0) || (v == 1), "invariant") ;
4325 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4326 }
4327 }
4329 void os::PlatformEvent::park() { // AKA "down()"
4330 // Invariant: Only the thread associated with the Event/PlatformEvent
4331 // may call park().
4332 // TODO: assert that _Assoc != NULL or _Assoc == Self
4333 int v ;
4334 for (;;) {
4335 v = _Event ;
4336 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4337 }
4338 guarantee (v >= 0, "invariant") ;
4339 if (v == 0) {
4340 // Do this the hard way by blocking ...
4341 int status = pthread_mutex_lock(_mutex);
4342 assert_status(status == 0, status, "mutex_lock");
4343 guarantee (_nParked == 0, "invariant") ;
4344 ++ _nParked ;
4345 while (_Event < 0) {
4346 status = pthread_cond_wait(_cond, _mutex);
4347 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4348 // Treat this the same as if the wait was interrupted
4349 if (status == ETIMEDOUT) { status = EINTR; }
4350 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4351 }
4352 -- _nParked ;
4354 _Event = 0 ;
4355 status = pthread_mutex_unlock(_mutex);
4356 assert_status(status == 0, status, "mutex_unlock");
4357 // Paranoia to ensure our locked and lock-free paths interact
4358 // correctly with each other.
4359 OrderAccess::fence();
4360 }
4361 guarantee (_Event >= 0, "invariant") ;
4362 }
4364 int os::PlatformEvent::park(jlong millis) {
4365 guarantee (_nParked == 0, "invariant") ;
4367 int v ;
4368 for (;;) {
4369 v = _Event ;
4370 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4371 }
4372 guarantee (v >= 0, "invariant") ;
4373 if (v != 0) return OS_OK ;
4375 // We do this the hard way, by blocking the thread.
4376 // Consider enforcing a minimum timeout value.
4377 struct timespec abst;
4378 compute_abstime(&abst, millis);
4380 int ret = OS_TIMEOUT;
4381 int status = pthread_mutex_lock(_mutex);
4382 assert_status(status == 0, status, "mutex_lock");
4383 guarantee (_nParked == 0, "invariant") ;
4384 ++_nParked ;
4386 // Object.wait(timo) will return because of
4387 // (a) notification
4388 // (b) timeout
4389 // (c) thread.interrupt
4390 //
4391 // Thread.interrupt and object.notify{All} both call Event::set.
4392 // That is, we treat thread.interrupt as a special case of notification.
4393 // The underlying Solaris implementation, cond_timedwait, admits
4394 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4395 // JVM from making those visible to Java code. As such, we must
4396 // filter out spurious wakeups. We assume all ETIME returns are valid.
4397 //
4398 // TODO: properly differentiate simultaneous notify+interrupt.
4399 // In that case, we should propagate the notify to another waiter.
4401 while (_Event < 0) {
4402 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4403 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4404 pthread_cond_destroy (_cond);
4405 pthread_cond_init (_cond, NULL) ;
4406 }
4407 assert_status(status == 0 || status == EINTR ||
4408 status == ETIMEDOUT,
4409 status, "cond_timedwait");
4410 if (!FilterSpuriousWakeups) break ; // previous semantics
4411 if (status == ETIMEDOUT) break ;
4412 // We consume and ignore EINTR and spurious wakeups.
4413 }
4414 --_nParked ;
4415 if (_Event >= 0) {
4416 ret = OS_OK;
4417 }
4418 _Event = 0 ;
4419 status = pthread_mutex_unlock(_mutex);
4420 assert_status(status == 0, status, "mutex_unlock");
4421 assert (_nParked == 0, "invariant") ;
4422 // Paranoia to ensure our locked and lock-free paths interact
4423 // correctly with each other.
4424 OrderAccess::fence();
4425 return ret;
4426 }
4428 void os::PlatformEvent::unpark() {
4429 // Transitions for _Event:
4430 // 0 :=> 1
4431 // 1 :=> 1
4432 // -1 :=> either 0 or 1; must signal target thread
4433 // That is, we can safely transition _Event from -1 to either
4434 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4435 // unpark() calls.
4436 // See also: "Semaphores in Plan 9" by Mullender & Cox
4437 //
4438 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4439 // that it will take two back-to-back park() calls for the owning
4440 // thread to block. This has the benefit of forcing a spurious return
4441 // from the first park() call after an unpark() call which will help
4442 // shake out uses of park() and unpark() without condition variables.
4444 if (Atomic::xchg(1, &_Event) >= 0) return;
4446 // Wait for the thread associated with the event to vacate
4447 int status = pthread_mutex_lock(_mutex);
4448 assert_status(status == 0, status, "mutex_lock");
4449 int AnyWaiters = _nParked;
4450 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4451 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4452 AnyWaiters = 0;
4453 pthread_cond_signal(_cond);
4454 }
4455 status = pthread_mutex_unlock(_mutex);
4456 assert_status(status == 0, status, "mutex_unlock");
4457 if (AnyWaiters != 0) {
4458 status = pthread_cond_signal(_cond);
4459 assert_status(status == 0, status, "cond_signal");
4460 }
4462 // Note that we signal() _after dropping the lock for "immortal" Events.
4463 // This is safe and avoids a common class of futile wakeups. In rare
4464 // circumstances this can cause a thread to return prematurely from
4465 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4466 // simply re-test the condition and re-park itself.
4467 }
4470 // JSR166
4471 // -------------------------------------------------------
4473 /*
4474 * The solaris and bsd implementations of park/unpark are fairly
4475 * conservative for now, but can be improved. They currently use a
4476 * mutex/condvar pair, plus a a count.
4477 * Park decrements count if > 0, else does a condvar wait. Unpark
4478 * sets count to 1 and signals condvar. Only one thread ever waits
4479 * on the condvar. Contention seen when trying to park implies that someone
4480 * is unparking you, so don't wait. And spurious returns are fine, so there
4481 * is no need to track notifications.
4482 */
4484 #define MAX_SECS 100000000
4485 /*
4486 * This code is common to bsd and solaris and will be moved to a
4487 * common place in dolphin.
4488 *
4489 * The passed in time value is either a relative time in nanoseconds
4490 * or an absolute time in milliseconds. Either way it has to be unpacked
4491 * into suitable seconds and nanoseconds components and stored in the
4492 * given timespec structure.
4493 * Given time is a 64-bit value and the time_t used in the timespec is only
4494 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4495 * overflow if times way in the future are given. Further on Solaris versions
4496 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4497 * number of seconds, in abstime, is less than current_time + 100,000,000.
4498 * As it will be 28 years before "now + 100000000" will overflow we can
4499 * ignore overflow and just impose a hard-limit on seconds using the value
4500 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4501 * years from "now".
4502 */
4504 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4505 assert (time > 0, "convertTime");
4507 struct timeval now;
4508 int status = gettimeofday(&now, NULL);
4509 assert(status == 0, "gettimeofday");
4511 time_t max_secs = now.tv_sec + MAX_SECS;
4513 if (isAbsolute) {
4514 jlong secs = time / 1000;
4515 if (secs > max_secs) {
4516 absTime->tv_sec = max_secs;
4517 }
4518 else {
4519 absTime->tv_sec = secs;
4520 }
4521 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4522 }
4523 else {
4524 jlong secs = time / NANOSECS_PER_SEC;
4525 if (secs >= MAX_SECS) {
4526 absTime->tv_sec = max_secs;
4527 absTime->tv_nsec = 0;
4528 }
4529 else {
4530 absTime->tv_sec = now.tv_sec + secs;
4531 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4532 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4533 absTime->tv_nsec -= NANOSECS_PER_SEC;
4534 ++absTime->tv_sec; // note: this must be <= max_secs
4535 }
4536 }
4537 }
4538 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4539 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4540 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4541 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4542 }
4544 void Parker::park(bool isAbsolute, jlong time) {
4545 // Ideally we'd do something useful while spinning, such
4546 // as calling unpackTime().
4548 // Optional fast-path check:
4549 // Return immediately if a permit is available.
4550 // We depend on Atomic::xchg() having full barrier semantics
4551 // since we are doing a lock-free update to _counter.
4552 if (Atomic::xchg(0, &_counter) > 0) return;
4554 Thread* thread = Thread::current();
4555 assert(thread->is_Java_thread(), "Must be JavaThread");
4556 JavaThread *jt = (JavaThread *)thread;
4558 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4559 // Check interrupt before trying to wait
4560 if (Thread::is_interrupted(thread, false)) {
4561 return;
4562 }
4564 // Next, demultiplex/decode time arguments
4565 struct timespec absTime;
4566 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4567 return;
4568 }
4569 if (time > 0) {
4570 unpackTime(&absTime, isAbsolute, time);
4571 }
4574 // Enter safepoint region
4575 // Beware of deadlocks such as 6317397.
4576 // The per-thread Parker:: mutex is a classic leaf-lock.
4577 // In particular a thread must never block on the Threads_lock while
4578 // holding the Parker:: mutex. If safepoints are pending both the
4579 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4580 ThreadBlockInVM tbivm(jt);
4582 // Don't wait if cannot get lock since interference arises from
4583 // unblocking. Also. check interrupt before trying wait
4584 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4585 return;
4586 }
4588 int status ;
4589 if (_counter > 0) { // no wait needed
4590 _counter = 0;
4591 status = pthread_mutex_unlock(_mutex);
4592 assert (status == 0, "invariant") ;
4593 // Paranoia to ensure our locked and lock-free paths interact
4594 // correctly with each other and Java-level accesses.
4595 OrderAccess::fence();
4596 return;
4597 }
4599 #ifdef ASSERT
4600 // Don't catch signals while blocked; let the running threads have the signals.
4601 // (This allows a debugger to break into the running thread.)
4602 sigset_t oldsigs;
4603 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4604 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4605 #endif
4607 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4608 jt->set_suspend_equivalent();
4609 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4611 if (time == 0) {
4612 status = pthread_cond_wait (_cond, _mutex) ;
4613 } else {
4614 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4615 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4616 pthread_cond_destroy (_cond) ;
4617 pthread_cond_init (_cond, NULL);
4618 }
4619 }
4620 assert_status(status == 0 || status == EINTR ||
4621 status == ETIMEDOUT,
4622 status, "cond_timedwait");
4624 #ifdef ASSERT
4625 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4626 #endif
4628 _counter = 0 ;
4629 status = pthread_mutex_unlock(_mutex) ;
4630 assert_status(status == 0, status, "invariant") ;
4631 // Paranoia to ensure our locked and lock-free paths interact
4632 // correctly with each other and Java-level accesses.
4633 OrderAccess::fence();
4635 // If externally suspended while waiting, re-suspend
4636 if (jt->handle_special_suspend_equivalent_condition()) {
4637 jt->java_suspend_self();
4638 }
4639 }
4641 void Parker::unpark() {
4642 int s, status ;
4643 status = pthread_mutex_lock(_mutex);
4644 assert (status == 0, "invariant") ;
4645 s = _counter;
4646 _counter = 1;
4647 if (s < 1) {
4648 if (WorkAroundNPTLTimedWaitHang) {
4649 status = pthread_cond_signal (_cond) ;
4650 assert (status == 0, "invariant") ;
4651 status = pthread_mutex_unlock(_mutex);
4652 assert (status == 0, "invariant") ;
4653 } else {
4654 status = pthread_mutex_unlock(_mutex);
4655 assert (status == 0, "invariant") ;
4656 status = pthread_cond_signal (_cond) ;
4657 assert (status == 0, "invariant") ;
4658 }
4659 } else {
4660 pthread_mutex_unlock(_mutex);
4661 assert (status == 0, "invariant") ;
4662 }
4663 }
4666 /* Darwin has no "environ" in a dynamic library. */
4667 #ifdef __APPLE__
4668 #include <crt_externs.h>
4669 #define environ (*_NSGetEnviron())
4670 #else
4671 extern char** environ;
4672 #endif
4674 // Run the specified command in a separate process. Return its exit value,
4675 // or -1 on failure (e.g. can't fork a new process).
4676 // Unlike system(), this function can be called from signal handler. It
4677 // doesn't block SIGINT et al.
4678 int os::fork_and_exec(char* cmd) {
4679 const char * argv[4] = {"sh", "-c", cmd, NULL};
4681 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4682 // pthread_atfork handlers and reset pthread library. All we need is a
4683 // separate process to execve. Make a direct syscall to fork process.
4684 // On IA64 there's no fork syscall, we have to use fork() and hope for
4685 // the best...
4686 pid_t pid = fork();
4688 if (pid < 0) {
4689 // fork failed
4690 return -1;
4692 } else if (pid == 0) {
4693 // child process
4695 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4696 // first to kill every thread on the thread list. Because this list is
4697 // not reset by fork() (see notes above), execve() will instead kill
4698 // every thread in the parent process. We know this is the only thread
4699 // in the new process, so make a system call directly.
4700 // IA64 should use normal execve() from glibc to match the glibc fork()
4701 // above.
4702 execve("/bin/sh", (char* const*)argv, environ);
4704 // execve failed
4705 _exit(-1);
4707 } else {
4708 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4709 // care about the actual exit code, for now.
4711 int status;
4713 // Wait for the child process to exit. This returns immediately if
4714 // the child has already exited. */
4715 while (waitpid(pid, &status, 0) < 0) {
4716 switch (errno) {
4717 case ECHILD: return 0;
4718 case EINTR: break;
4719 default: return -1;
4720 }
4721 }
4723 if (WIFEXITED(status)) {
4724 // The child exited normally; get its exit code.
4725 return WEXITSTATUS(status);
4726 } else if (WIFSIGNALED(status)) {
4727 // The child exited because of a signal
4728 // The best value to return is 0x80 + signal number,
4729 // because that is what all Unix shells do, and because
4730 // it allows callers to distinguish between process exit and
4731 // process death by signal.
4732 return 0x80 + WTERMSIG(status);
4733 } else {
4734 // Unknown exit code; pass it through
4735 return status;
4736 }
4737 }
4738 }
4740 // is_headless_jre()
4741 //
4742 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4743 // in order to report if we are running in a headless jre
4744 //
4745 // Since JDK8 xawt/libmawt.so was moved into the same directory
4746 // as libawt.so, and renamed libawt_xawt.so
4747 //
4748 bool os::is_headless_jre() {
4749 struct stat statbuf;
4750 char buf[MAXPATHLEN];
4751 char libmawtpath[MAXPATHLEN];
4752 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4753 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4754 char *p;
4756 // Get path to libjvm.so
4757 os::jvm_path(buf, sizeof(buf));
4759 // Get rid of libjvm.so
4760 p = strrchr(buf, '/');
4761 if (p == NULL) return false;
4762 else *p = '\0';
4764 // Get rid of client or server
4765 p = strrchr(buf, '/');
4766 if (p == NULL) return false;
4767 else *p = '\0';
4769 // check xawt/libmawt.so
4770 strcpy(libmawtpath, buf);
4771 strcat(libmawtpath, xawtstr);
4772 if (::stat(libmawtpath, &statbuf) == 0) return false;
4774 // check libawt_xawt.so
4775 strcpy(libmawtpath, buf);
4776 strcat(libmawtpath, new_xawtstr);
4777 if (::stat(libmawtpath, &statbuf) == 0) return false;
4779 return true;
4780 }
4782 // Get the default path to the core file
4783 // Returns the length of the string
4784 int os::get_core_path(char* buffer, size_t bufferSize) {
4785 int n = jio_snprintf(buffer, bufferSize, "/cores");
4787 // Truncate if theoretical string was longer than bufferSize
4788 n = MIN2(n, (int)bufferSize);
4790 return n;
4791 }
4793 #ifndef PRODUCT
4794 void TestReserveMemorySpecial_test() {
4795 // No tests available for this platform
4796 }
4797 #endif