1 /*
2 * Copyright (c) 1999, 2017, 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 */
24
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 "logging/log.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "memory/filemap.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_bsd.inline.hpp"
40 #include "os_share_bsd.hpp"
41 #include "prims/jniFastGetField.hpp"
42 #include "prims/jvm.h"
43 #include "prims/jvm_misc.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/atomic.hpp"
46 #include "runtime/extendedPC.hpp"
47 #include "runtime/globals.hpp"
48 #include "runtime/interfaceSupport.hpp"
49 #include "runtime/java.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/mutexLocker.hpp"
52 #include "runtime/objectMonitor.hpp"
53 #include "runtime/orderAccess.inline.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/perfMemory.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/statSampler.hpp"
58 #include "runtime/stubRoutines.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "runtime/threadCritical.hpp"
61 #include "runtime/timer.hpp"
62 #include "semaphore_bsd.hpp"
63 #include "services/attachListener.hpp"
64 #include "services/memTracker.hpp"
65 #include "services/runtimeService.hpp"
66 #include "utilities/decoder.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69 #include "utilities/growableArray.hpp"
70 #include "utilities/vmError.hpp"
71
72 // put OS-includes here
73 # include <sys/types.h>
74 # include <sys/mman.h>
75 # include <sys/stat.h>
76 # include <sys/select.h>
77 # include <pthread.h>
78 # include <signal.h>
79 # include <errno.h>
80 # include <dlfcn.h>
81 # include <stdio.h>
82 # include <unistd.h>
83 # include <sys/resource.h>
84 # include <pthread.h>
85 # include <sys/stat.h>
86 # include <sys/time.h>
87 # include <sys/times.h>
88 # include <sys/utsname.h>
89 # include <sys/socket.h>
90 # include <sys/wait.h>
91 # include <time.h>
92 # include <pwd.h>
93 # include <poll.h>
94 # include <semaphore.h>
95 # include <fcntl.h>
96 # include <string.h>
97 # include <sys/param.h>
98 # include <sys/sysctl.h>
99 # include <sys/ipc.h>
100 # include <sys/shm.h>
101 #ifndef __APPLE__
102 # include <link.h>
103 #endif
104 # include <stdint.h>
105 # include <inttypes.h>
106 # include <sys/ioctl.h>
107 # include <sys/syscall.h>
108
109 #if defined(__FreeBSD__) || defined(__NetBSD__)
110 #include <elf.h>
111 #endif
112
113 #ifdef __APPLE__
114 #include <mach/mach.h> // semaphore_* API
115 #include <mach-o/dyld.h>
116 #include <sys/proc_info.h>
117 #include <objc/objc-auto.h>
118 #endif
119
120 #ifndef MAP_ANONYMOUS
121 #define MAP_ANONYMOUS MAP_ANON
122 #endif
123
124 #define MAX_PATH (2 * K)
125
126 // for timer info max values which include all bits
127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
128
129 #define LARGEPAGES_BIT (1 << 6)
130
131 ////////////////////////////////////////////////////////////////////////////////
132 // global variables
133 julong os::Bsd::_physical_memory = 0;
134
135 #ifdef __APPLE__
136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
137 volatile uint64_t os::Bsd::_max_abstime = 0;
138 #else
139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
140 #endif
141 pthread_t os::Bsd::_main_thread;
142 int os::Bsd::_page_size = -1;
143
144 static jlong initial_time_count=0;
145
146 static int clock_tics_per_sec = 100;
147
148 // For diagnostics to print a message once. see run_periodic_checks
149 static sigset_t check_signal_done;
150 static bool check_signals = true;
151
152 static pid_t _initial_pid = 0;
153
154 // Signal number used to suspend/resume a thread
155
156 // do not use any signal number less than SIGSEGV, see 4355769
157 static int SR_signum = SIGUSR2;
158 sigset_t SR_sigset;
159
160
161 ////////////////////////////////////////////////////////////////////////////////
162 // utility functions
163
164 static int SR_initialize();
165 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
166
167 julong os::available_memory() {
168 return Bsd::available_memory();
169 }
170
171 // available here means free
172 julong os::Bsd::available_memory() {
173 uint64_t available = physical_memory() >> 2;
174 #ifdef __APPLE__
175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
176 vm_statistics64_data_t vmstat;
177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
178 (host_info64_t)&vmstat, &count);
179 assert(kerr == KERN_SUCCESS,
180 "host_statistics64 failed - check mach_host_self() and count");
181 if (kerr == KERN_SUCCESS) {
182 available = vmstat.free_count * os::vm_page_size();
183 }
184 #endif
185 return available;
186 }
187
188 julong os::physical_memory() {
189 return Bsd::physical_memory();
190 }
191
192 // Return true if user is running as root.
193
194 bool os::have_special_privileges() {
195 static bool init = false;
196 static bool privileges = false;
197 if (!init) {
198 privileges = (getuid() != geteuid()) || (getgid() != getegid());
199 init = true;
200 }
201 return privileges;
202 }
203
204
205
206 // Cpu architecture string
207 #if defined(ZERO)
208 static char cpu_arch[] = ZERO_LIBARCH;
209 #elif defined(IA64)
210 static char cpu_arch[] = "ia64";
211 #elif defined(IA32)
212 static char cpu_arch[] = "i386";
213 #elif defined(AMD64)
214 static char cpu_arch[] = "amd64";
215 #elif defined(ARM)
216 static char cpu_arch[] = "arm";
217 #elif defined(PPC32)
218 static char cpu_arch[] = "ppc";
219 #elif defined(SPARC)
220 #ifdef _LP64
221 static char cpu_arch[] = "sparcv9";
222 #else
223 static char cpu_arch[] = "sparc";
224 #endif
225 #else
226 #error Add appropriate cpu_arch setting
227 #endif
228
229 // Compiler variant
230 #ifdef COMPILER2
231 #define COMPILER_VARIANT "server"
232 #else
233 #define COMPILER_VARIANT "client"
234 #endif
235
236
237 void os::Bsd::initialize_system_info() {
238 int mib[2];
239 size_t len;
240 int cpu_val;
241 julong mem_val;
242
243 // get processors count via hw.ncpus sysctl
244 mib[0] = CTL_HW;
245 mib[1] = HW_NCPU;
246 len = sizeof(cpu_val);
247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
248 assert(len == sizeof(cpu_val), "unexpected data size");
249 set_processor_count(cpu_val);
250 } else {
251 set_processor_count(1); // fallback
252 }
253
254 // get physical memory via hw.memsize sysctl (hw.memsize is used
255 // since it returns a 64 bit value)
256 mib[0] = CTL_HW;
257
258 #if defined (HW_MEMSIZE) // Apple
259 mib[1] = HW_MEMSIZE;
260 #elif defined(HW_PHYSMEM) // Most of BSD
261 mib[1] = HW_PHYSMEM;
262 #elif defined(HW_REALMEM) // Old FreeBSD
263 mib[1] = HW_REALMEM;
264 #else
265 #error No ways to get physmem
266 #endif
267
268 len = sizeof(mem_val);
269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
270 assert(len == sizeof(mem_val), "unexpected data size");
271 _physical_memory = mem_val;
272 } else {
273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
274 }
275
276 #ifdef __OpenBSD__
277 {
278 // limit _physical_memory memory view on OpenBSD since
279 // datasize rlimit restricts us anyway.
280 struct rlimit limits;
281 getrlimit(RLIMIT_DATA, &limits);
282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
283 }
284 #endif
285 }
286
287 #ifdef __APPLE__
288 static const char *get_home() {
289 const char *home_dir = ::getenv("HOME");
290 if ((home_dir == NULL) || (*home_dir == '\0')) {
291 struct passwd *passwd_info = getpwuid(geteuid());
292 if (passwd_info != NULL) {
293 home_dir = passwd_info->pw_dir;
294 }
295 }
296
297 return home_dir;
298 }
299 #endif
300
301 void os::init_system_properties_values() {
302 // The next steps are taken in the product version:
303 //
304 // Obtain the JAVA_HOME value from the location of libjvm.so.
305 // This library should be located at:
306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
307 //
308 // If "/jre/lib/" appears at the right place in the path, then we
309 // assume libjvm.so is installed in a JDK and we use this path.
310 //
311 // Otherwise exit with message: "Could not create the Java virtual machine."
312 //
313 // The following extra steps are taken in the debugging version:
314 //
315 // If "/jre/lib/" does NOT appear at the right place in the path
316 // instead of exit check for $JAVA_HOME environment variable.
317 //
318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
319 // then we append a fake suffix "hotspot/libjvm.so" to this path so
320 // it looks like libjvm.so is installed there
321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
322 //
323 // Otherwise exit.
324 //
325 // Important note: if the location of libjvm.so changes this
326 // code needs to be changed accordingly.
327
328 // See ld(1):
329 // The linker uses the following search paths to locate required
330 // shared libraries:
331 // 1: ...
332 // ...
333 // 7: The default directories, normally /lib and /usr/lib.
334 #ifndef DEFAULT_LIBPATH
335 #define DEFAULT_LIBPATH "/lib:/usr/lib"
336 #endif
337
338 // Base path of extensions installed on the system.
339 #define SYS_EXT_DIR "/usr/java/packages"
340 #define EXTENSIONS_DIR "/lib/ext"
341
342 #ifndef __APPLE__
343
344 // Buffer that fits several sprintfs.
345 // Note that the space for the colon and the trailing null are provided
346 // by the nulls included by the sizeof operator.
347 const size_t bufsize =
348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
351
352 // sysclasspath, java_home, dll_dir
353 {
354 char *pslash;
355 os::jvm_path(buf, bufsize);
356
357 // Found the full path to libjvm.so.
358 // Now cut the path to <java_home>/jre if we can.
359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
360 pslash = strrchr(buf, '/');
361 if (pslash != NULL) {
362 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
363 }
364 Arguments::set_dll_dir(buf);
365
366 if (pslash != NULL) {
367 pslash = strrchr(buf, '/');
368 if (pslash != NULL) {
369 *pslash = '\0'; // Get rid of /<arch>.
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL) {
372 *pslash = '\0'; // Get rid of /lib.
373 }
374 }
375 }
376 Arguments::set_java_home(buf);
377 set_boot_path('/', ':');
378 }
379
380 // Where to look for native libraries.
381 //
382 // Note: Due to a legacy implementation, most of the library path
383 // is set in the launcher. This was to accomodate linking restrictions
384 // on legacy Bsd implementations (which are no longer supported).
385 // Eventually, all the library path setting will be done here.
386 //
387 // However, to prevent the proliferation of improperly built native
388 // libraries, the new path component /usr/java/packages is added here.
389 // Eventually, all the library path setting will be done here.
390 {
391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
392 // should always exist (until the legacy problem cited above is
393 // addressed).
394 const char *v = ::getenv("LD_LIBRARY_PATH");
395 const char *v_colon = ":";
396 if (v == NULL) { v = ""; v_colon = ""; }
397 // That's +1 for the colon and +1 for the trailing '\0'.
398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
399 strlen(v) + 1 +
400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
401 mtInternal);
402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
403 Arguments::set_library_path(ld_library_path);
404 FREE_C_HEAP_ARRAY(char, ld_library_path);
405 }
406
407 // Extensions directories.
408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
409 Arguments::set_ext_dirs(buf);
410
411 FREE_C_HEAP_ARRAY(char, buf);
412
413 #else // __APPLE__
414
415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
417
418 const char *user_home_dir = get_home();
419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
421 sizeof(SYS_EXTENSIONS_DIRS);
422
423 // Buffer that fits several sprintfs.
424 // Note that the space for the colon and the trailing null are provided
425 // by the nulls included by the sizeof operator.
426 const size_t bufsize =
427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
430
431 // sysclasspath, java_home, dll_dir
432 {
433 char *pslash;
434 os::jvm_path(buf, bufsize);
435
436 // Found the full path to libjvm.so.
437 // Now cut the path to <java_home>/jre if we can.
438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
439 pslash = strrchr(buf, '/');
440 if (pslash != NULL) {
441 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
442 }
443 #ifdef STATIC_BUILD
444 strcat(buf, "/lib");
445 #endif
446
447 Arguments::set_dll_dir(buf);
448
449 if (pslash != NULL) {
450 pslash = strrchr(buf, '/');
451 if (pslash != NULL) {
452 *pslash = '\0'; // Get rid of /lib.
453 }
454 }
455 Arguments::set_java_home(buf);
456 set_boot_path('/', ':');
457 }
458
459 // Where to look for native libraries.
460 //
461 // Note: Due to a legacy implementation, most of the library path
462 // is set in the launcher. This was to accomodate linking restrictions
463 // on legacy Bsd implementations (which are no longer supported).
464 // Eventually, all the library path setting will be done here.
465 //
466 // However, to prevent the proliferation of improperly built native
467 // libraries, the new path component /usr/java/packages is added here.
468 // Eventually, all the library path setting will be done here.
469 {
470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
471 // should always exist (until the legacy problem cited above is
472 // addressed).
473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
474 // can specify a directory inside an app wrapper
475 const char *l = ::getenv("JAVA_LIBRARY_PATH");
476 const char *l_colon = ":";
477 if (l == NULL) { l = ""; l_colon = ""; }
478
479 const char *v = ::getenv("DYLD_LIBRARY_PATH");
480 const char *v_colon = ":";
481 if (v == NULL) { v = ""; v_colon = ""; }
482
483 // Apple's Java6 has "." at the beginning of java.library.path.
484 // OpenJDK on Windows has "." at the end of java.library.path.
485 // OpenJDK on Linux and Solaris don't have "." in java.library.path
486 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
487 // "." is appended to the end of java.library.path. Yes, this
488 // could cause a change in behavior, but Apple's Java6 behavior
489 // can be achieved by putting "." at the beginning of the
490 // JAVA_LIBRARY_PATH environment variable.
491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
492 strlen(v) + 1 + strlen(l) + 1 +
493 system_ext_size + 3,
494 mtInternal);
495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
496 v, v_colon, l, l_colon, user_home_dir);
497 Arguments::set_library_path(ld_library_path);
498 FREE_C_HEAP_ARRAY(char, ld_library_path);
499 }
500
501 // Extensions directories.
502 //
503 // Note that the space for the colon and the trailing null are provided
504 // by the nulls included by the sizeof operator (so actually one byte more
505 // than necessary is allocated).
506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
507 user_home_dir, Arguments::get_java_home());
508 Arguments::set_ext_dirs(buf);
509
510 FREE_C_HEAP_ARRAY(char, buf);
511
512 #undef SYS_EXTENSIONS_DIR
513 #undef SYS_EXTENSIONS_DIRS
514
515 #endif // __APPLE__
516
517 #undef SYS_EXT_DIR
518 #undef EXTENSIONS_DIR
519 }
520
521 ////////////////////////////////////////////////////////////////////////////////
522 // breakpoint support
523
524 void os::breakpoint() {
525 BREAKPOINT;
526 }
527
528 extern "C" void breakpoint() {
529 // use debugger to set breakpoint here
530 }
531
532 ////////////////////////////////////////////////////////////////////////////////
533 // signal support
534
535 debug_only(static bool signal_sets_initialized = false);
536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
537
538 bool os::Bsd::is_sig_ignored(int sig) {
539 struct sigaction oact;
540 sigaction(sig, (struct sigaction*)NULL, &oact);
541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
542 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
544 return true;
545 } else {
546 return false;
547 }
548 }
549
550 void os::Bsd::signal_sets_init() {
551 // Should also have an assertion stating we are still single-threaded.
552 assert(!signal_sets_initialized, "Already initialized");
553 // Fill in signals that are necessarily unblocked for all threads in
554 // the VM. Currently, we unblock the following signals:
555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
556 // by -Xrs (=ReduceSignalUsage));
557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
559 // the dispositions or masks wrt these signals.
560 // Programs embedding the VM that want to use the above signals for their
561 // own purposes must, at this time, use the "-Xrs" option to prevent
562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
563 // (See bug 4345157, and other related bugs).
564 // In reality, though, unblocking these signals is really a nop, since
565 // these signals are not blocked by default.
566 sigemptyset(&unblocked_sigs);
567 sigemptyset(&allowdebug_blocked_sigs);
568 sigaddset(&unblocked_sigs, SIGILL);
569 sigaddset(&unblocked_sigs, SIGSEGV);
570 sigaddset(&unblocked_sigs, SIGBUS);
571 sigaddset(&unblocked_sigs, SIGFPE);
572 sigaddset(&unblocked_sigs, SR_signum);
573
574 if (!ReduceSignalUsage) {
575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
578 }
579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
582 }
583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
586 }
587 }
588 // Fill in signals that are blocked by all but the VM thread.
589 sigemptyset(&vm_sigs);
590 if (!ReduceSignalUsage) {
591 sigaddset(&vm_sigs, BREAK_SIGNAL);
592 }
593 debug_only(signal_sets_initialized = true);
594
595 }
596
597 // These are signals that are unblocked while a thread is running Java.
598 // (For some reason, they get blocked by default.)
599 sigset_t* os::Bsd::unblocked_signals() {
600 assert(signal_sets_initialized, "Not initialized");
601 return &unblocked_sigs;
602 }
603
604 // These are the signals that are blocked while a (non-VM) thread is
605 // running Java. Only the VM thread handles these signals.
606 sigset_t* os::Bsd::vm_signals() {
607 assert(signal_sets_initialized, "Not initialized");
608 return &vm_sigs;
609 }
610
611 // These are signals that are blocked during cond_wait to allow debugger in
612 sigset_t* os::Bsd::allowdebug_blocked_signals() {
613 assert(signal_sets_initialized, "Not initialized");
614 return &allowdebug_blocked_sigs;
615 }
616
617 void os::Bsd::hotspot_sigmask(Thread* thread) {
618
619 //Save caller's signal mask before setting VM signal mask
620 sigset_t caller_sigmask;
621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
622
623 OSThread* osthread = thread->osthread();
624 osthread->set_caller_sigmask(caller_sigmask);
625
626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
627
628 if (!ReduceSignalUsage) {
629 if (thread->is_VM_thread()) {
630 // Only the VM thread handles BREAK_SIGNAL ...
631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
632 } else {
633 // ... all other threads block BREAK_SIGNAL
634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
635 }
636 }
637 }
638
639
640 //////////////////////////////////////////////////////////////////////////////
641 // create new thread
642
643 #ifdef __APPLE__
644 // library handle for calling objc_registerThreadWithCollector()
645 // without static linking to the libobjc library
646 #define OBJC_LIB "/usr/lib/libobjc.dylib"
647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
648 typedef void (*objc_registerThreadWithCollector_t)();
649 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
650 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
651 #endif
652
653 #ifdef __APPLE__
654 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
655 // Additional thread_id used to correlate threads in SA
656 thread_identifier_info_data_t m_ident_info;
657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
658
659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
660 (thread_info_t) &m_ident_info, &count);
661
662 return m_ident_info.thread_id;
663 }
664 #endif
665
666 // Thread start routine for all newly created threads
667 static void *thread_native_entry(Thread *thread) {
668 // Try to randomize the cache line index of hot stack frames.
669 // This helps when threads of the same stack traces evict each other's
670 // cache lines. The threads can be either from the same JVM instance, or
671 // from different JVM instances. The benefit is especially true for
672 // processors with hyperthreading technology.
673 static int counter = 0;
674 int pid = os::current_process_id();
675 alloca(((pid ^ counter++) & 7) * 128);
676
677 thread->initialize_thread_current();
678
679 OSThread* osthread = thread->osthread();
680 Monitor* sync = osthread->startThread_lock();
681
682 osthread->set_thread_id(os::Bsd::gettid());
683
684 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
685 os::current_thread_id(), (uintx) pthread_self());
686
687 #ifdef __APPLE__
688 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
689 guarantee(unique_thread_id != 0, "unique thread id was not found");
690 osthread->set_unique_thread_id(unique_thread_id);
691 #endif
692 // initialize signal mask for this thread
693 os::Bsd::hotspot_sigmask(thread);
694
695 // initialize floating point control register
696 os::Bsd::init_thread_fpu_state();
697
698 #ifdef __APPLE__
699 // register thread with objc gc
700 if (objc_registerThreadWithCollectorFunction != NULL) {
701 objc_registerThreadWithCollectorFunction();
702 }
703 #endif
704
705 // handshaking with parent thread
706 {
707 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
708
709 // notify parent thread
710 osthread->set_state(INITIALIZED);
711 sync->notify_all();
712
713 // wait until os::start_thread()
714 while (osthread->get_state() == INITIALIZED) {
715 sync->wait(Mutex::_no_safepoint_check_flag);
716 }
717 }
718
719 // call one more level start routine
720 thread->run();
721
722 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
723 os::current_thread_id(), (uintx) pthread_self());
724
725 // If a thread has not deleted itself ("delete this") as part of its
726 // termination sequence, we have to ensure thread-local-storage is
727 // cleared before we actually terminate. No threads should ever be
728 // deleted asynchronously with respect to their termination.
729 if (Thread::current_or_null_safe() != NULL) {
730 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
731 thread->clear_thread_current();
732 }
733
734 return 0;
735 }
736
737 bool os::create_thread(Thread* thread, ThreadType thr_type,
738 size_t req_stack_size) {
739 assert(thread->osthread() == NULL, "caller responsible");
740
741 // Allocate the OSThread object
742 OSThread* osthread = new OSThread(NULL, NULL);
743 if (osthread == NULL) {
744 return false;
745 }
746
747 // set the correct thread state
748 osthread->set_thread_type(thr_type);
749
750 // Initial state is ALLOCATED but not INITIALIZED
751 osthread->set_state(ALLOCATED);
752
753 thread->set_osthread(osthread);
754
755 // init thread attributes
756 pthread_attr_t attr;
757 pthread_attr_init(&attr);
758 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
759
760 // calculate stack size if it's not specified by caller
761 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
762 int status = pthread_attr_setstacksize(&attr, stack_size);
763 assert_status(status == 0, status, "pthread_attr_setstacksize");
764
765 ThreadState state;
766
767 {
768 pthread_t tid;
769 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
770
771 char buf[64];
772 if (ret == 0) {
773 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
774 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
775 } else {
776 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
777 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
778 }
779
780 pthread_attr_destroy(&attr);
781
782 if (ret != 0) {
783 // Need to clean up stuff we've allocated so far
784 thread->set_osthread(NULL);
785 delete osthread;
786 return false;
787 }
788
789 // Store pthread info into the OSThread
790 osthread->set_pthread_id(tid);
791
792 // Wait until child thread is either initialized or aborted
793 {
794 Monitor* sync_with_child = osthread->startThread_lock();
795 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
796 while ((state = osthread->get_state()) == ALLOCATED) {
797 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
798 }
799 }
800
801 }
802
803 // Aborted due to thread limit being reached
804 if (state == ZOMBIE) {
805 thread->set_osthread(NULL);
806 delete osthread;
807 return false;
808 }
809
810 // The thread is returned suspended (in state INITIALIZED),
811 // and is started higher up in the call chain
812 assert(state == INITIALIZED, "race condition");
813 return true;
814 }
815
816 /////////////////////////////////////////////////////////////////////////////
817 // attach existing thread
818
819 // bootstrap the main thread
820 bool os::create_main_thread(JavaThread* thread) {
821 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
822 return create_attached_thread(thread);
823 }
824
825 bool os::create_attached_thread(JavaThread* thread) {
826 #ifdef ASSERT
827 thread->verify_not_published();
828 #endif
829
830 // Allocate the OSThread object
831 OSThread* osthread = new OSThread(NULL, NULL);
832
833 if (osthread == NULL) {
834 return false;
835 }
836
837 osthread->set_thread_id(os::Bsd::gettid());
838
839 // Store pthread info into the OSThread
840 #ifdef __APPLE__
841 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
842 guarantee(unique_thread_id != 0, "just checking");
843 osthread->set_unique_thread_id(unique_thread_id);
844 #endif
845 osthread->set_pthread_id(::pthread_self());
846
847 // initialize floating point control register
848 os::Bsd::init_thread_fpu_state();
849
850 // Initial thread state is RUNNABLE
851 osthread->set_state(RUNNABLE);
852
853 thread->set_osthread(osthread);
854
855 // initialize signal mask for this thread
856 // and save the caller's signal mask
857 os::Bsd::hotspot_sigmask(thread);
858
859 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
860 os::current_thread_id(), (uintx) pthread_self());
861
862 return true;
863 }
864
865 void os::pd_start_thread(Thread* thread) {
866 OSThread * osthread = thread->osthread();
867 assert(osthread->get_state() != INITIALIZED, "just checking");
868 Monitor* sync_with_child = osthread->startThread_lock();
869 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
870 sync_with_child->notify();
871 }
872
873 // Free Bsd resources related to the OSThread
874 void os::free_thread(OSThread* osthread) {
875 assert(osthread != NULL, "osthread not set");
876
877 // We are told to free resources of the argument thread,
878 // but we can only really operate on the current thread.
879 assert(Thread::current()->osthread() == osthread,
880 "os::free_thread but not current thread");
881
882 // Restore caller's signal mask
883 sigset_t sigmask = osthread->caller_sigmask();
884 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
885
886 delete osthread;
887 }
888
889 ////////////////////////////////////////////////////////////////////////////////
890 // time support
891
892 // Time since start-up in seconds to a fine granularity.
893 // Used by VMSelfDestructTimer and the MemProfiler.
894 double os::elapsedTime() {
895
896 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
897 }
898
899 jlong os::elapsed_counter() {
900 return javaTimeNanos() - initial_time_count;
901 }
902
903 jlong os::elapsed_frequency() {
904 return NANOSECS_PER_SEC; // nanosecond resolution
905 }
906
907 bool os::supports_vtime() { return true; }
908 bool os::enable_vtime() { return false; }
909 bool os::vtime_enabled() { return false; }
910
911 double os::elapsedVTime() {
912 // better than nothing, but not much
913 return elapsedTime();
914 }
915
916 jlong os::javaTimeMillis() {
917 timeval time;
918 int status = gettimeofday(&time, NULL);
919 assert(status != -1, "bsd error");
920 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
921 }
922
923 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
924 timeval time;
925 int status = gettimeofday(&time, NULL);
926 assert(status != -1, "bsd error");
927 seconds = jlong(time.tv_sec);
928 nanos = jlong(time.tv_usec) * 1000;
929 }
930
931 #ifndef __APPLE__
932 #ifndef CLOCK_MONOTONIC
933 #define CLOCK_MONOTONIC (1)
934 #endif
935 #endif
936
937 #ifdef __APPLE__
938 void os::Bsd::clock_init() {
939 mach_timebase_info(&_timebase_info);
940 }
941 #else
942 void os::Bsd::clock_init() {
943 struct timespec res;
944 struct timespec tp;
945 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
946 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
947 // yes, monotonic clock is supported
948 _clock_gettime = ::clock_gettime;
949 }
950 }
951 #endif
952
953
954
955 #ifdef __APPLE__
956
957 jlong os::javaTimeNanos() {
958 const uint64_t tm = mach_absolute_time();
959 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
960 const uint64_t prev = Bsd::_max_abstime;
961 if (now <= prev) {
962 return prev; // same or retrograde time;
963 }
964 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
965 assert(obsv >= prev, "invariant"); // Monotonicity
966 // If the CAS succeeded then we're done and return "now".
967 // If the CAS failed and the observed value "obsv" is >= now then
968 // we should return "obsv". If the CAS failed and now > obsv > prv then
969 // some other thread raced this thread and installed a new value, in which case
970 // we could either (a) retry the entire operation, (b) retry trying to install now
971 // or (c) just return obsv. We use (c). No loop is required although in some cases
972 // we might discard a higher "now" value in deference to a slightly lower but freshly
973 // installed obsv value. That's entirely benign -- it admits no new orderings compared
974 // to (a) or (b) -- and greatly reduces coherence traffic.
975 // We might also condition (c) on the magnitude of the delta between obsv and now.
976 // Avoiding excessive CAS operations to hot RW locations is critical.
977 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
978 return (prev == obsv) ? now : obsv;
979 }
980
981 #else // __APPLE__
982
983 jlong os::javaTimeNanos() {
984 if (os::supports_monotonic_clock()) {
985 struct timespec tp;
986 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
987 assert(status == 0, "gettime error");
988 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
989 return result;
990 } else {
991 timeval time;
992 int status = gettimeofday(&time, NULL);
993 assert(status != -1, "bsd error");
994 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
995 return 1000 * usecs;
996 }
997 }
998
999 #endif // __APPLE__
1000
1001 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1002 if (os::supports_monotonic_clock()) {
1003 info_ptr->max_value = ALL_64_BITS;
1004
1005 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1006 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1007 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1008 } else {
1009 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1010 info_ptr->max_value = ALL_64_BITS;
1011
1012 // gettimeofday is a real time clock so it skips
1013 info_ptr->may_skip_backward = true;
1014 info_ptr->may_skip_forward = true;
1015 }
1016
1017 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1018 }
1019
1020 // Return the real, user, and system times in seconds from an
1021 // arbitrary fixed point in the past.
1022 bool os::getTimesSecs(double* process_real_time,
1023 double* process_user_time,
1024 double* process_system_time) {
1025 struct tms ticks;
1026 clock_t real_ticks = times(&ticks);
1027
1028 if (real_ticks == (clock_t) (-1)) {
1029 return false;
1030 } else {
1031 double ticks_per_second = (double) clock_tics_per_sec;
1032 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1033 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1034 *process_real_time = ((double) real_ticks) / ticks_per_second;
1035
1036 return true;
1037 }
1038 }
1039
1040
1041 char * os::local_time_string(char *buf, size_t buflen) {
1042 struct tm t;
1043 time_t long_time;
1044 time(&long_time);
1045 localtime_r(&long_time, &t);
1046 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1047 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1048 t.tm_hour, t.tm_min, t.tm_sec);
1049 return buf;
1050 }
1051
1052 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1053 return localtime_r(clock, res);
1054 }
1055
1056 ////////////////////////////////////////////////////////////////////////////////
1057 // runtime exit support
1058
1059 // Note: os::shutdown() might be called very early during initialization, or
1060 // called from signal handler. Before adding something to os::shutdown(), make
1061 // sure it is async-safe and can handle partially initialized VM.
1062 void os::shutdown() {
1063
1064 // allow PerfMemory to attempt cleanup of any persistent resources
1065 perfMemory_exit();
1066
1067 // needs to remove object in file system
1068 AttachListener::abort();
1069
1070 // flush buffered output, finish log files
1071 ostream_abort();
1072
1073 // Check for abort hook
1074 abort_hook_t abort_hook = Arguments::abort_hook();
1075 if (abort_hook != NULL) {
1076 abort_hook();
1077 }
1078
1079 }
1080
1081 // Note: os::abort() might be called very early during initialization, or
1082 // called from signal handler. Before adding something to os::abort(), make
1083 // sure it is async-safe and can handle partially initialized VM.
1084 void os::abort(bool dump_core, void* siginfo, const void* context) {
1085 os::shutdown();
1086 if (dump_core) {
1087 #ifndef PRODUCT
1088 fdStream out(defaultStream::output_fd());
1089 out.print_raw("Current thread is ");
1090 char buf[16];
1091 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1092 out.print_raw_cr(buf);
1093 out.print_raw_cr("Dumping core ...");
1094 #endif
1095 ::abort(); // dump core
1096 }
1097
1098 ::exit(1);
1099 }
1100
1101 // Die immediately, no exit hook, no abort hook, no cleanup.
1102 void os::die() {
1103 // _exit() on BsdThreads only kills current thread
1104 ::abort();
1105 }
1106
1107 // This method is a copy of JDK's sysGetLastErrorString
1108 // from src/solaris/hpi/src/system_md.c
1109
1110 size_t os::lasterror(char *buf, size_t len) {
1111 if (errno == 0) return 0;
1112
1113 const char *s = os::strerror(errno);
1114 size_t n = ::strlen(s);
1115 if (n >= len) {
1116 n = len - 1;
1117 }
1118 ::strncpy(buf, s, n);
1119 buf[n] = '\0';
1120 return n;
1121 }
1122
1123 // Information of current thread in variety of formats
1124 pid_t os::Bsd::gettid() {
1125 int retval = -1;
1126
1127 #ifdef __APPLE__ //XNU kernel
1128 // despite the fact mach port is actually not a thread id use it
1129 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1130 retval = ::pthread_mach_thread_np(::pthread_self());
1131 guarantee(retval != 0, "just checking");
1132 return retval;
1133
1134 #else
1135 #ifdef __FreeBSD__
1136 retval = syscall(SYS_thr_self);
1137 #else
1138 #ifdef __OpenBSD__
1139 retval = syscall(SYS_getthrid);
1140 #else
1141 #ifdef __NetBSD__
1142 retval = (pid_t) syscall(SYS__lwp_self);
1143 #endif
1144 #endif
1145 #endif
1146 #endif
1147
1148 if (retval == -1) {
1149 return getpid();
1150 }
1151 }
1152
1153 intx os::current_thread_id() {
1154 #ifdef __APPLE__
1155 return (intx)::pthread_mach_thread_np(::pthread_self());
1156 #else
1157 return (intx)::pthread_self();
1158 #endif
1159 }
1160
1161 int os::current_process_id() {
1162
1163 // Under the old bsd thread library, bsd gives each thread
1164 // its own process id. Because of this each thread will return
1165 // a different pid if this method were to return the result
1166 // of getpid(2). Bsd provides no api that returns the pid
1167 // of the launcher thread for the vm. This implementation
1168 // returns a unique pid, the pid of the launcher thread
1169 // that starts the vm 'process'.
1170
1171 // Under the NPTL, getpid() returns the same pid as the
1172 // launcher thread rather than a unique pid per thread.
1173 // Use gettid() if you want the old pre NPTL behaviour.
1174
1175 // if you are looking for the result of a call to getpid() that
1176 // returns a unique pid for the calling thread, then look at the
1177 // OSThread::thread_id() method in osThread_bsd.hpp file
1178
1179 return (int)(_initial_pid ? _initial_pid : getpid());
1180 }
1181
1182 // DLL functions
1183
1184 #define JNI_LIB_PREFIX "lib"
1185 #ifdef __APPLE__
1186 #define JNI_LIB_SUFFIX ".dylib"
1187 #else
1188 #define JNI_LIB_SUFFIX ".so"
1189 #endif
1190
1191 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1192
1193 // This must be hard coded because it's the system's temporary
1194 // directory not the java application's temp directory, ala java.io.tmpdir.
1195 #ifdef __APPLE__
1196 // macosx has a secure per-user temporary directory
1197 char temp_path_storage[PATH_MAX];
1198 const char* os::get_temp_directory() {
1199 static char *temp_path = NULL;
1200 if (temp_path == NULL) {
1201 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1202 if (pathSize == 0 || pathSize > PATH_MAX) {
1203 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1204 }
1205 temp_path = temp_path_storage;
1206 }
1207 return temp_path;
1208 }
1209 #else // __APPLE__
1210 const char* os::get_temp_directory() { return "/tmp"; }
1211 #endif // __APPLE__
1212
1213 static bool file_exists(const char* filename) {
1214 struct stat statbuf;
1215 if (filename == NULL || strlen(filename) == 0) {
1216 return false;
1217 }
1218 return os::stat(filename, &statbuf) == 0;
1219 }
1220
1221 bool os::dll_build_name(char* buffer, size_t buflen,
1222 const char* pname, const char* fname) {
1223 bool retval = false;
1224 // Copied from libhpi
1225 const size_t pnamelen = pname ? strlen(pname) : 0;
1226
1227 // Return error on buffer overflow.
1228 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1229 return retval;
1230 }
1231
1232 if (pnamelen == 0) {
1233 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1234 retval = true;
1235 } else if (strchr(pname, *os::path_separator()) != NULL) {
1236 int n;
1237 char** pelements = split_path(pname, &n);
1238 if (pelements == NULL) {
1239 return false;
1240 }
1241 for (int i = 0; i < n; i++) {
1242 // Really shouldn't be NULL, but check can't hurt
1243 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1244 continue; // skip the empty path values
1245 }
1246 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1247 pelements[i], fname);
1248 if (file_exists(buffer)) {
1249 retval = true;
1250 break;
1251 }
1252 }
1253 // release the storage
1254 for (int i = 0; i < n; i++) {
1255 if (pelements[i] != NULL) {
1256 FREE_C_HEAP_ARRAY(char, pelements[i]);
1257 }
1258 }
1259 if (pelements != NULL) {
1260 FREE_C_HEAP_ARRAY(char*, pelements);
1261 }
1262 } else {
1263 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1264 retval = true;
1265 }
1266 return retval;
1267 }
1268
1269 // check if addr is inside libjvm.so
1270 bool os::address_is_in_vm(address addr) {
1271 static address libjvm_base_addr;
1272 Dl_info dlinfo;
1273
1274 if (libjvm_base_addr == NULL) {
1275 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1276 libjvm_base_addr = (address)dlinfo.dli_fbase;
1277 }
1278 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1279 }
1280
1281 if (dladdr((void *)addr, &dlinfo) != 0) {
1282 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1283 }
1284
1285 return false;
1286 }
1287
1288
1289 #define MACH_MAXSYMLEN 256
1290
1291 bool os::dll_address_to_function_name(address addr, char *buf,
1292 int buflen, int *offset,
1293 bool demangle) {
1294 // buf is not optional, but offset is optional
1295 assert(buf != NULL, "sanity check");
1296
1297 Dl_info dlinfo;
1298 char localbuf[MACH_MAXSYMLEN];
1299
1300 if (dladdr((void*)addr, &dlinfo) != 0) {
1301 // see if we have a matching symbol
1302 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1303 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1304 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1305 }
1306 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1307 return true;
1308 }
1309 // no matching symbol so try for just file info
1310 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1311 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1312 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1313 return true;
1314 }
1315 }
1316
1317 // Handle non-dynamic manually:
1318 if (dlinfo.dli_fbase != NULL &&
1319 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1320 dlinfo.dli_fbase)) {
1321 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1322 jio_snprintf(buf, buflen, "%s", localbuf);
1323 }
1324 return true;
1325 }
1326 }
1327 buf[0] = '\0';
1328 if (offset != NULL) *offset = -1;
1329 return false;
1330 }
1331
1332 // ported from solaris version
1333 bool os::dll_address_to_library_name(address addr, char* buf,
1334 int buflen, int* offset) {
1335 // buf is not optional, but offset is optional
1336 assert(buf != NULL, "sanity check");
1337
1338 Dl_info dlinfo;
1339
1340 if (dladdr((void*)addr, &dlinfo) != 0) {
1341 if (dlinfo.dli_fname != NULL) {
1342 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1343 }
1344 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1345 *offset = addr - (address)dlinfo.dli_fbase;
1346 }
1347 return true;
1348 }
1349
1350 buf[0] = '\0';
1351 if (offset) *offset = -1;
1352 return false;
1353 }
1354
1355 // Loads .dll/.so and
1356 // in case of error it checks if .dll/.so was built for the
1357 // same architecture as Hotspot is running on
1358
1359 #ifdef __APPLE__
1360 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1361 #ifdef STATIC_BUILD
1362 return os::get_default_process_handle();
1363 #else
1364 void * result= ::dlopen(filename, RTLD_LAZY);
1365 if (result != NULL) {
1366 // Successful loading
1367 return result;
1368 }
1369
1370 // Read system error message into ebuf
1371 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1372 ebuf[ebuflen-1]='\0';
1373
1374 return NULL;
1375 #endif // STATIC_BUILD
1376 }
1377 #else
1378 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1379 #ifdef STATIC_BUILD
1380 return os::get_default_process_handle();
1381 #else
1382 void * result= ::dlopen(filename, RTLD_LAZY);
1383 if (result != NULL) {
1384 // Successful loading
1385 return result;
1386 }
1387
1388 Elf32_Ehdr elf_head;
1389
1390 // Read system error message into ebuf
1391 // It may or may not be overwritten below
1392 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1393 ebuf[ebuflen-1]='\0';
1394 int diag_msg_max_length=ebuflen-strlen(ebuf);
1395 char* diag_msg_buf=ebuf+strlen(ebuf);
1396
1397 if (diag_msg_max_length==0) {
1398 // No more space in ebuf for additional diagnostics message
1399 return NULL;
1400 }
1401
1402
1403 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1404
1405 if (file_descriptor < 0) {
1406 // Can't open library, report dlerror() message
1407 return NULL;
1408 }
1409
1410 bool failed_to_read_elf_head=
1411 (sizeof(elf_head)!=
1412 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1413
1414 ::close(file_descriptor);
1415 if (failed_to_read_elf_head) {
1416 // file i/o error - report dlerror() msg
1417 return NULL;
1418 }
1419
1420 typedef struct {
1421 Elf32_Half code; // Actual value as defined in elf.h
1422 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1423 char elf_class; // 32 or 64 bit
1424 char endianess; // MSB or LSB
1425 char* name; // String representation
1426 } arch_t;
1427
1428 #ifndef EM_486
1429 #define EM_486 6 /* Intel 80486 */
1430 #endif
1431
1432 #ifndef EM_MIPS_RS3_LE
1433 #define EM_MIPS_RS3_LE 10 /* MIPS */
1434 #endif
1435
1436 #ifndef EM_PPC64
1437 #define EM_PPC64 21 /* PowerPC64 */
1438 #endif
1439
1440 #ifndef EM_S390
1441 #define EM_S390 22 /* IBM System/390 */
1442 #endif
1443
1444 #ifndef EM_IA_64
1445 #define EM_IA_64 50 /* HP/Intel IA-64 */
1446 #endif
1447
1448 #ifndef EM_X86_64
1449 #define EM_X86_64 62 /* AMD x86-64 */
1450 #endif
1451
1452 static const arch_t arch_array[]={
1453 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1454 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1455 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1456 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1457 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1458 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1459 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1460 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1461 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1462 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1463 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1464 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1465 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1466 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1467 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1468 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1469 };
1470
1471 #if (defined IA32)
1472 static Elf32_Half running_arch_code=EM_386;
1473 #elif (defined AMD64)
1474 static Elf32_Half running_arch_code=EM_X86_64;
1475 #elif (defined IA64)
1476 static Elf32_Half running_arch_code=EM_IA_64;
1477 #elif (defined __sparc) && (defined _LP64)
1478 static Elf32_Half running_arch_code=EM_SPARCV9;
1479 #elif (defined __sparc) && (!defined _LP64)
1480 static Elf32_Half running_arch_code=EM_SPARC;
1481 #elif (defined __powerpc64__)
1482 static Elf32_Half running_arch_code=EM_PPC64;
1483 #elif (defined __powerpc__)
1484 static Elf32_Half running_arch_code=EM_PPC;
1485 #elif (defined ARM)
1486 static Elf32_Half running_arch_code=EM_ARM;
1487 #elif (defined S390)
1488 static Elf32_Half running_arch_code=EM_S390;
1489 #elif (defined ALPHA)
1490 static Elf32_Half running_arch_code=EM_ALPHA;
1491 #elif (defined MIPSEL)
1492 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1493 #elif (defined PARISC)
1494 static Elf32_Half running_arch_code=EM_PARISC;
1495 #elif (defined MIPS)
1496 static Elf32_Half running_arch_code=EM_MIPS;
1497 #elif (defined M68K)
1498 static Elf32_Half running_arch_code=EM_68K;
1499 #else
1500 #error Method os::dll_load requires that one of following is defined:\
1501 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1502 #endif
1503
1504 // Identify compatability class for VM's architecture and library's architecture
1505 // Obtain string descriptions for architectures
1506
1507 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1508 int running_arch_index=-1;
1509
1510 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1511 if (running_arch_code == arch_array[i].code) {
1512 running_arch_index = i;
1513 }
1514 if (lib_arch.code == arch_array[i].code) {
1515 lib_arch.compat_class = arch_array[i].compat_class;
1516 lib_arch.name = arch_array[i].name;
1517 }
1518 }
1519
1520 assert(running_arch_index != -1,
1521 "Didn't find running architecture code (running_arch_code) in arch_array");
1522 if (running_arch_index == -1) {
1523 // Even though running architecture detection failed
1524 // we may still continue with reporting dlerror() message
1525 return NULL;
1526 }
1527
1528 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1529 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1530 return NULL;
1531 }
1532
1533 #ifndef S390
1534 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1535 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1536 return NULL;
1537 }
1538 #endif // !S390
1539
1540 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1541 if (lib_arch.name!=NULL) {
1542 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1543 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1544 lib_arch.name, arch_array[running_arch_index].name);
1545 } else {
1546 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1547 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1548 lib_arch.code,
1549 arch_array[running_arch_index].name);
1550 }
1551 }
1552
1553 return NULL;
1554 #endif // STATIC_BUILD
1555 }
1556 #endif // !__APPLE__
1557
1558 void* os::get_default_process_handle() {
1559 #ifdef __APPLE__
1560 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1561 // to avoid finding unexpected symbols on second (or later)
1562 // loads of a library.
1563 return (void*)::dlopen(NULL, RTLD_FIRST);
1564 #else
1565 return (void*)::dlopen(NULL, RTLD_LAZY);
1566 #endif
1567 }
1568
1569 // XXX: Do we need a lock around this as per Linux?
1570 void* os::dll_lookup(void* handle, const char* name) {
1571 return dlsym(handle, name);
1572 }
1573
1574 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1575 outputStream * out = (outputStream *) param;
1576 out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1577 return 0;
1578 }
1579
1580 void os::print_dll_info(outputStream *st) {
1581 st->print_cr("Dynamic libraries:");
1582 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1583 st->print_cr("Error: Cannot print dynamic libraries.");
1584 }
1585 }
1586
1587 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1588 #ifdef RTLD_DI_LINKMAP
1589 Dl_info dli;
1590 void *handle;
1591 Link_map *map;
1592 Link_map *p;
1593
1594 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1595 dli.dli_fname == NULL) {
1596 return 1;
1597 }
1598 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1599 if (handle == NULL) {
1600 return 1;
1601 }
1602 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1603 if (map == NULL) {
1604 dlclose(handle);
1605 return 1;
1606 }
1607
1608 while (map->l_prev != NULL)
1609 map = map->l_prev;
1610
1611 while (map != NULL) {
1612 // Value for top_address is returned as 0 since we don't have any information about module size
1613 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1614 dlclose(handle);
1615 return 1;
1616 }
1617 map = map->l_next;
1618 }
1619
1620 dlclose(handle);
1621 #elif defined(__APPLE__)
1622 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1623 // Value for top_address is returned as 0 since we don't have any information about module size
1624 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1625 return 1;
1626 }
1627 }
1628 return 0;
1629 #else
1630 return 1;
1631 #endif
1632 }
1633
1634 void os::get_summary_os_info(char* buf, size_t buflen) {
1635 // These buffers are small because we want this to be brief
1636 // and not use a lot of stack while generating the hs_err file.
1637 char os[100];
1638 size_t size = sizeof(os);
1639 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1640 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1641 #ifdef __APPLE__
1642 strncpy(os, "Darwin", sizeof(os));
1643 #elif __OpenBSD__
1644 strncpy(os, "OpenBSD", sizeof(os));
1645 #else
1646 strncpy(os, "BSD", sizeof(os));
1647 #endif
1648 }
1649
1650 char release[100];
1651 size = sizeof(release);
1652 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1653 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1654 // if error, leave blank
1655 strncpy(release, "", sizeof(release));
1656 }
1657 snprintf(buf, buflen, "%s %s", os, release);
1658 }
1659
1660 void os::print_os_info_brief(outputStream* st) {
1661 os::Posix::print_uname_info(st);
1662 }
1663
1664 void os::print_os_info(outputStream* st) {
1665 st->print("OS:");
1666
1667 os::Posix::print_uname_info(st);
1668
1669 os::Posix::print_rlimit_info(st);
1670
1671 os::Posix::print_load_average(st);
1672 }
1673
1674 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1675 // Nothing to do for now.
1676 }
1677
1678 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1679 unsigned int mhz;
1680 size_t size = sizeof(mhz);
1681 int mib[] = { CTL_HW, HW_CPU_FREQ };
1682 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1683 mhz = 1; // looks like an error but can be divided by
1684 } else {
1685 mhz /= 1000000; // reported in millions
1686 }
1687
1688 char model[100];
1689 size = sizeof(model);
1690 int mib_model[] = { CTL_HW, HW_MODEL };
1691 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1692 strncpy(model, cpu_arch, sizeof(model));
1693 }
1694
1695 char machine[100];
1696 size = sizeof(machine);
1697 int mib_machine[] = { CTL_HW, HW_MACHINE };
1698 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1699 strncpy(machine, "", sizeof(machine));
1700 }
1701
1702 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1703 }
1704
1705 void os::print_memory_info(outputStream* st) {
1706
1707 st->print("Memory:");
1708 st->print(" %dk page", os::vm_page_size()>>10);
1709
1710 st->print(", physical " UINT64_FORMAT "k",
1711 os::physical_memory() >> 10);
1712 st->print("(" UINT64_FORMAT "k free)",
1713 os::available_memory() >> 10);
1714 st->cr();
1715 }
1716
1717 static void print_signal_handler(outputStream* st, int sig,
1718 char* buf, size_t buflen);
1719
1720 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1721 st->print_cr("Signal Handlers:");
1722 print_signal_handler(st, SIGSEGV, buf, buflen);
1723 print_signal_handler(st, SIGBUS , buf, buflen);
1724 print_signal_handler(st, SIGFPE , buf, buflen);
1725 print_signal_handler(st, SIGPIPE, buf, buflen);
1726 print_signal_handler(st, SIGXFSZ, buf, buflen);
1727 print_signal_handler(st, SIGILL , buf, buflen);
1728 print_signal_handler(st, SR_signum, buf, buflen);
1729 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1730 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1731 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1732 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1733 }
1734
1735 static char saved_jvm_path[MAXPATHLEN] = {0};
1736
1737 // Find the full path to the current module, libjvm
1738 void os::jvm_path(char *buf, jint buflen) {
1739 // Error checking.
1740 if (buflen < MAXPATHLEN) {
1741 assert(false, "must use a large-enough buffer");
1742 buf[0] = '\0';
1743 return;
1744 }
1745 // Lazy resolve the path to current module.
1746 if (saved_jvm_path[0] != 0) {
1747 strcpy(buf, saved_jvm_path);
1748 return;
1749 }
1750
1751 char dli_fname[MAXPATHLEN];
1752 bool ret = dll_address_to_library_name(
1753 CAST_FROM_FN_PTR(address, os::jvm_path),
1754 dli_fname, sizeof(dli_fname), NULL);
1755 assert(ret, "cannot locate libjvm");
1756 char *rp = NULL;
1757 if (ret && dli_fname[0] != '\0') {
1758 rp = os::Posix::realpath(dli_fname, buf, buflen);
1759 }
1760 if (rp == NULL) {
1761 return;
1762 }
1763
1764 if (Arguments::sun_java_launcher_is_altjvm()) {
1765 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1766 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1767 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1768 // appears at the right place in the string, then assume we are
1769 // installed in a JDK and we're done. Otherwise, check for a
1770 // JAVA_HOME environment variable and construct a path to the JVM
1771 // being overridden.
1772
1773 const char *p = buf + strlen(buf) - 1;
1774 for (int count = 0; p > buf && count < 5; ++count) {
1775 for (--p; p > buf && *p != '/'; --p)
1776 /* empty */ ;
1777 }
1778
1779 if (strncmp(p, "/jre/lib/", 9) != 0) {
1780 // Look for JAVA_HOME in the environment.
1781 char* java_home_var = ::getenv("JAVA_HOME");
1782 if (java_home_var != NULL && java_home_var[0] != 0) {
1783 char* jrelib_p;
1784 int len;
1785
1786 // Check the current module name "libjvm"
1787 p = strrchr(buf, '/');
1788 assert(strstr(p, "/libjvm") == p, "invalid library name");
1789
1790 rp = os::Posix::realpath(java_home_var, buf, buflen);
1791 if (rp == NULL) {
1792 return;
1793 }
1794
1795 // determine if this is a legacy image or modules image
1796 // modules image doesn't have "jre" subdirectory
1797 len = strlen(buf);
1798 assert(len < buflen, "Ran out of buffer space");
1799 jrelib_p = buf + len;
1800
1801 // Add the appropriate library subdir
1802 snprintf(jrelib_p, buflen-len, "/jre/lib");
1803 if (0 != access(buf, F_OK)) {
1804 snprintf(jrelib_p, buflen-len, "/lib");
1805 }
1806
1807 // Add the appropriate client or server subdir
1808 len = strlen(buf);
1809 jrelib_p = buf + len;
1810 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1811 if (0 != access(buf, F_OK)) {
1812 snprintf(jrelib_p, buflen-len, "%s", "");
1813 }
1814
1815 // If the path exists within JAVA_HOME, add the JVM library name
1816 // to complete the path to JVM being overridden. Otherwise fallback
1817 // to the path to the current library.
1818 if (0 == access(buf, F_OK)) {
1819 // Use current module name "libjvm"
1820 len = strlen(buf);
1821 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1822 } else {
1823 // Fall back to path of current library
1824 rp = os::Posix::realpath(dli_fname, buf, buflen);
1825 if (rp == NULL) {
1826 return;
1827 }
1828 }
1829 }
1830 }
1831 }
1832
1833 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1834 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1835 }
1836
1837 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1838 // no prefix required, not even "_"
1839 }
1840
1841 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1842 // no suffix required
1843 }
1844
1845 ////////////////////////////////////////////////////////////////////////////////
1846 // sun.misc.Signal support
1847
1848 static volatile jint sigint_count = 0;
1849
1850 static void UserHandler(int sig, void *siginfo, void *context) {
1851 // 4511530 - sem_post is serialized and handled by the manager thread. When
1852 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1853 // don't want to flood the manager thread with sem_post requests.
1854 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1855 return;
1856 }
1857
1858 // Ctrl-C is pressed during error reporting, likely because the error
1859 // handler fails to abort. Let VM die immediately.
1860 if (sig == SIGINT && is_error_reported()) {
1861 os::die();
1862 }
1863
1864 os::signal_notify(sig);
1865 }
1866
1867 void* os::user_handler() {
1868 return CAST_FROM_FN_PTR(void*, UserHandler);
1869 }
1870
1871 extern "C" {
1872 typedef void (*sa_handler_t)(int);
1873 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1874 }
1875
1876 void* os::signal(int signal_number, void* handler) {
1877 struct sigaction sigAct, oldSigAct;
1878
1879 sigfillset(&(sigAct.sa_mask));
1880 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1881 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1882
1883 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1884 // -1 means registration failed
1885 return (void *)-1;
1886 }
1887
1888 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1889 }
1890
1891 void os::signal_raise(int signal_number) {
1892 ::raise(signal_number);
1893 }
1894
1895 // The following code is moved from os.cpp for making this
1896 // code platform specific, which it is by its very nature.
1897
1898 // Will be modified when max signal is changed to be dynamic
1899 int os::sigexitnum_pd() {
1900 return NSIG;
1901 }
1902
1903 // a counter for each possible signal value
1904 static volatile jint pending_signals[NSIG+1] = { 0 };
1905
1906 // Bsd(POSIX) specific hand shaking semaphore.
1907 #ifdef __APPLE__
1908 typedef semaphore_t os_semaphore_t;
1909
1910 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1911 #define SEM_WAIT(sem) semaphore_wait(sem)
1912 #define SEM_POST(sem) semaphore_signal(sem)
1913 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1914 #else
1915 typedef sem_t os_semaphore_t;
1916
1917 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1918 #define SEM_WAIT(sem) sem_wait(&sem)
1919 #define SEM_POST(sem) sem_post(&sem)
1920 #define SEM_DESTROY(sem) sem_destroy(&sem)
1921 #endif
1922
1923 #ifdef __APPLE__
1924 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
1925
1926 static const char* sem_init_strerror(kern_return_t value) {
1927 switch (value) {
1928 case KERN_INVALID_ARGUMENT: return "Invalid argument";
1929 case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
1930 default: return "Unknown";
1931 }
1932 }
1933
1934 OSXSemaphore::OSXSemaphore(uint value) {
1935 kern_return_t ret = SEM_INIT(_semaphore, value);
1936
1937 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
1938 }
1939
1940 OSXSemaphore::~OSXSemaphore() {
1941 SEM_DESTROY(_semaphore);
1942 }
1943
1944 void OSXSemaphore::signal(uint count) {
1945 for (uint i = 0; i < count; i++) {
1946 kern_return_t ret = SEM_POST(_semaphore);
1947
1948 assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
1949 }
1950 }
1951
1952 void OSXSemaphore::wait() {
1953 kern_return_t ret;
1954 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
1955 // Semaphore was interrupted. Retry.
1956 }
1957 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
1958 }
1959
1960 jlong OSXSemaphore::currenttime() {
1961 struct timeval tv;
1962 gettimeofday(&tv, NULL);
1963 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1964 }
1965
1966 bool OSXSemaphore::trywait() {
1967 return timedwait(0, 0);
1968 }
1969
1970 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
1971 kern_return_t kr = KERN_ABORTED;
1972 mach_timespec_t waitspec;
1973 waitspec.tv_sec = sec;
1974 waitspec.tv_nsec = nsec;
1975
1976 jlong starttime = currenttime();
1977
1978 kr = semaphore_timedwait(_semaphore, waitspec);
1979 while (kr == KERN_ABORTED) {
1980 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1981
1982 jlong current = currenttime();
1983 jlong passedtime = current - starttime;
1984
1985 if (passedtime >= totalwait) {
1986 waitspec.tv_sec = 0;
1987 waitspec.tv_nsec = 0;
1988 } else {
1989 jlong waittime = totalwait - (current - starttime);
1990 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1991 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1992 }
1993
1994 kr = semaphore_timedwait(_semaphore, waitspec);
1995 }
1996
1997 return kr == KERN_SUCCESS;
1998 }
1999
2000 #else
2001 // Use POSIX implementation of semaphores.
2002
2003 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
2004 struct timespec ts;
2005 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2006
2007 return ts;
2008 }
2009
2010 #endif // __APPLE__
2011
2012 static os_semaphore_t sig_sem;
2013
2014 #ifdef __APPLE__
2015 static OSXSemaphore sr_semaphore;
2016 #else
2017 static PosixSemaphore sr_semaphore;
2018 #endif
2019
2020 void os::signal_init_pd() {
2021 // Initialize signal structures
2022 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2023
2024 // Initialize signal semaphore
2025 ::SEM_INIT(sig_sem, 0);
2026 }
2027
2028 void os::signal_notify(int sig) {
2029 Atomic::inc(&pending_signals[sig]);
2030 ::SEM_POST(sig_sem);
2031 }
2032
2033 static int check_pending_signals(bool wait) {
2034 Atomic::store(0, &sigint_count);
2035 for (;;) {
2036 for (int i = 0; i < NSIG + 1; i++) {
2037 jint n = pending_signals[i];
2038 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2039 return i;
2040 }
2041 }
2042 if (!wait) {
2043 return -1;
2044 }
2045 JavaThread *thread = JavaThread::current();
2046 ThreadBlockInVM tbivm(thread);
2047
2048 bool threadIsSuspended;
2049 do {
2050 thread->set_suspend_equivalent();
2051 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2052 ::SEM_WAIT(sig_sem);
2053
2054 // were we externally suspended while we were waiting?
2055 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2056 if (threadIsSuspended) {
2057 // The semaphore has been incremented, but while we were waiting
2058 // another thread suspended us. We don't want to continue running
2059 // while suspended because that would surprise the thread that
2060 // suspended us.
2061 ::SEM_POST(sig_sem);
2062
2063 thread->java_suspend_self();
2064 }
2065 } while (threadIsSuspended);
2066 }
2067 }
2068
2069 int os::signal_lookup() {
2070 return check_pending_signals(false);
2071 }
2072
2073 int os::signal_wait() {
2074 return check_pending_signals(true);
2075 }
2076
2077 ////////////////////////////////////////////////////////////////////////////////
2078 // Virtual Memory
2079
2080 int os::vm_page_size() {
2081 // Seems redundant as all get out
2082 assert(os::Bsd::page_size() != -1, "must call os::init");
2083 return os::Bsd::page_size();
2084 }
2085
2086 // Solaris allocates memory by pages.
2087 int os::vm_allocation_granularity() {
2088 assert(os::Bsd::page_size() != -1, "must call os::init");
2089 return os::Bsd::page_size();
2090 }
2091
2092 // Rationale behind this function:
2093 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2094 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2095 // samples for JITted code. Here we create private executable mapping over the code cache
2096 // and then we can use standard (well, almost, as mapping can change) way to provide
2097 // info for the reporting script by storing timestamp and location of symbol
2098 void bsd_wrap_code(char* base, size_t size) {
2099 static volatile jint cnt = 0;
2100
2101 if (!UseOprofile) {
2102 return;
2103 }
2104
2105 char buf[PATH_MAX + 1];
2106 int num = Atomic::add(1, &cnt);
2107
2108 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2109 os::get_temp_directory(), os::current_process_id(), num);
2110 unlink(buf);
2111
2112 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2113
2114 if (fd != -1) {
2115 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2116 if (rv != (off_t)-1) {
2117 if (::write(fd, "", 1) == 1) {
2118 mmap(base, size,
2119 PROT_READ|PROT_WRITE|PROT_EXEC,
2120 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2121 }
2122 }
2123 ::close(fd);
2124 unlink(buf);
2125 }
2126 }
2127
2128 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2129 int err) {
2130 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2131 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2132 os::errno_name(err), err);
2133 }
2134
2135 // NOTE: Bsd kernel does not really reserve the pages for us.
2136 // All it does is to check if there are enough free pages
2137 // left at the time of mmap(). This could be a potential
2138 // problem.
2139 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2140 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2141 #ifdef __OpenBSD__
2142 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2143 if (::mprotect(addr, size, prot) == 0) {
2144 return true;
2145 }
2146 #else
2147 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2148 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2149 if (res != (uintptr_t) MAP_FAILED) {
2150 return true;
2151 }
2152 #endif
2153
2154 // Warn about any commit errors we see in non-product builds just
2155 // in case mmap() doesn't work as described on the man page.
2156 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2157
2158 return false;
2159 }
2160
2161 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2162 bool exec) {
2163 // alignment_hint is ignored on this OS
2164 return pd_commit_memory(addr, size, exec);
2165 }
2166
2167 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2168 const char* mesg) {
2169 assert(mesg != NULL, "mesg must be specified");
2170 if (!pd_commit_memory(addr, size, exec)) {
2171 // add extra info in product mode for vm_exit_out_of_memory():
2172 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2173 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
2174 }
2175 }
2176
2177 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2178 size_t alignment_hint, bool exec,
2179 const char* mesg) {
2180 // alignment_hint is ignored on this OS
2181 pd_commit_memory_or_exit(addr, size, exec, mesg);
2182 }
2183
2184 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2185 }
2186
2187 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2188 ::madvise(addr, bytes, MADV_DONTNEED);
2189 }
2190
2191 void os::numa_make_global(char *addr, size_t bytes) {
2192 }
2193
2194 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2195 }
2196
2197 bool os::numa_topology_changed() { return false; }
2198
2199 size_t os::numa_get_groups_num() {
2200 return 1;
2201 }
2202
2203 int os::numa_get_group_id() {
2204 return 0;
2205 }
2206
2207 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2208 if (size > 0) {
2209 ids[0] = 0;
2210 return 1;
2211 }
2212 return 0;
2213 }
2214
2215 bool os::get_page_info(char *start, page_info* info) {
2216 return false;
2217 }
2218
2219 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2220 return end;
2221 }
2222
2223
2224 bool os::pd_uncommit_memory(char* addr, size_t size) {
2225 #ifdef __OpenBSD__
2226 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2227 return ::mprotect(addr, size, PROT_NONE) == 0;
2228 #else
2229 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2230 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2231 return res != (uintptr_t) MAP_FAILED;
2232 #endif
2233 }
2234
2235 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2236 return os::commit_memory(addr, size, !ExecMem);
2237 }
2238
2239 // If this is a growable mapping, remove the guard pages entirely by
2240 // munmap()ping them. If not, just call uncommit_memory().
2241 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2242 return os::uncommit_memory(addr, size);
2243 }
2244
2245 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2246 // at 'requested_addr'. If there are existing memory mappings at the same
2247 // location, however, they will be overwritten. If 'fixed' is false,
2248 // 'requested_addr' is only treated as a hint, the return value may or
2249 // may not start from the requested address. Unlike Bsd mmap(), this
2250 // function returns NULL to indicate failure.
2251 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2252 char * addr;
2253 int flags;
2254
2255 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2256 if (fixed) {
2257 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2258 flags |= MAP_FIXED;
2259 }
2260
2261 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2262 // touch an uncommitted page. Otherwise, the read/write might
2263 // succeed if we have enough swap space to back the physical page.
2264 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2265 flags, -1, 0);
2266
2267 return addr == MAP_FAILED ? NULL : addr;
2268 }
2269
2270 static int anon_munmap(char * addr, size_t size) {
2271 return ::munmap(addr, size) == 0;
2272 }
2273
2274 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2275 size_t alignment_hint) {
2276 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2277 }
2278
2279 bool os::pd_release_memory(char* addr, size_t size) {
2280 return anon_munmap(addr, size);
2281 }
2282
2283 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2284 // Bsd wants the mprotect address argument to be page aligned.
2285 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2286
2287 // According to SUSv3, mprotect() should only be used with mappings
2288 // established by mmap(), and mmap() always maps whole pages. Unaligned
2289 // 'addr' likely indicates problem in the VM (e.g. trying to change
2290 // protection of malloc'ed or statically allocated memory). Check the
2291 // caller if you hit this assert.
2292 assert(addr == bottom, "sanity check");
2293
2294 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2295 return ::mprotect(bottom, size, prot) == 0;
2296 }
2297
2298 // Set protections specified
2299 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2300 bool is_committed) {
2301 unsigned int p = 0;
2302 switch (prot) {
2303 case MEM_PROT_NONE: p = PROT_NONE; break;
2304 case MEM_PROT_READ: p = PROT_READ; break;
2305 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2306 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2307 default:
2308 ShouldNotReachHere();
2309 }
2310 // is_committed is unused.
2311 return bsd_mprotect(addr, bytes, p);
2312 }
2313
2314 bool os::guard_memory(char* addr, size_t size) {
2315 return bsd_mprotect(addr, size, PROT_NONE);
2316 }
2317
2318 bool os::unguard_memory(char* addr, size_t size) {
2319 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2320 }
2321
2322 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2323 return false;
2324 }
2325
2326 // Large page support
2327
2328 static size_t _large_page_size = 0;
2329
2330 void os::large_page_init() {
2331 }
2332
2333
2334 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2335 fatal("This code is not used or maintained.");
2336
2337 // "exec" is passed in but not used. Creating the shared image for
2338 // the code cache doesn't have an SHM_X executable permission to check.
2339 assert(UseLargePages && UseSHM, "only for SHM large pages");
2340
2341 key_t key = IPC_PRIVATE;
2342 char *addr;
2343
2344 bool warn_on_failure = UseLargePages &&
2345 (!FLAG_IS_DEFAULT(UseLargePages) ||
2346 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2347
2348 // Create a large shared memory region to attach to based on size.
2349 // Currently, size is the total size of the heap
2350 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2351 if (shmid == -1) {
2352 // Possible reasons for shmget failure:
2353 // 1. shmmax is too small for Java heap.
2354 // > check shmmax value: cat /proc/sys/kernel/shmmax
2355 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2356 // 2. not enough large page memory.
2357 // > check available large pages: cat /proc/meminfo
2358 // > increase amount of large pages:
2359 // echo new_value > /proc/sys/vm/nr_hugepages
2360 // Note 1: different Bsd may use different name for this property,
2361 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2362 // Note 2: it's possible there's enough physical memory available but
2363 // they are so fragmented after a long run that they can't
2364 // coalesce into large pages. Try to reserve large pages when
2365 // the system is still "fresh".
2366 if (warn_on_failure) {
2367 warning("Failed to reserve shared memory (errno = %d).", errno);
2368 }
2369 return NULL;
2370 }
2371
2372 // attach to the region
2373 addr = (char*)shmat(shmid, req_addr, 0);
2374 int err = errno;
2375
2376 // Remove shmid. If shmat() is successful, the actual shared memory segment
2377 // will be deleted when it's detached by shmdt() or when the process
2378 // terminates. If shmat() is not successful this will remove the shared
2379 // segment immediately.
2380 shmctl(shmid, IPC_RMID, NULL);
2381
2382 if ((intptr_t)addr == -1) {
2383 if (warn_on_failure) {
2384 warning("Failed to attach shared memory (errno = %d).", err);
2385 }
2386 return NULL;
2387 }
2388
2389 // The memory is committed
2390 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2391
2392 return addr;
2393 }
2394
2395 bool os::release_memory_special(char* base, size_t bytes) {
2396 if (MemTracker::tracking_level() > NMT_minimal) {
2397 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2398 // detaching the SHM segment will also delete it, see reserve_memory_special()
2399 int rslt = shmdt(base);
2400 if (rslt == 0) {
2401 tkr.record((address)base, bytes);
2402 return true;
2403 } else {
2404 return false;
2405 }
2406 } else {
2407 return shmdt(base) == 0;
2408 }
2409 }
2410
2411 size_t os::large_page_size() {
2412 return _large_page_size;
2413 }
2414
2415 // HugeTLBFS allows application to commit large page memory on demand;
2416 // with SysV SHM the entire memory region must be allocated as shared
2417 // memory.
2418 bool os::can_commit_large_page_memory() {
2419 return UseHugeTLBFS;
2420 }
2421
2422 bool os::can_execute_large_page_memory() {
2423 return UseHugeTLBFS;
2424 }
2425
2426 // Reserve memory at an arbitrary address, only if that area is
2427 // available (and not reserved for something else).
2428
2429 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2430 const int max_tries = 10;
2431 char* base[max_tries];
2432 size_t size[max_tries];
2433 const size_t gap = 0x000000;
2434
2435 // Assert only that the size is a multiple of the page size, since
2436 // that's all that mmap requires, and since that's all we really know
2437 // about at this low abstraction level. If we need higher alignment,
2438 // we can either pass an alignment to this method or verify alignment
2439 // in one of the methods further up the call chain. See bug 5044738.
2440 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2441
2442 // Repeatedly allocate blocks until the block is allocated at the
2443 // right spot.
2444
2445 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2446 // if kernel honors the hint then we can return immediately.
2447 char * addr = anon_mmap(requested_addr, bytes, false);
2448 if (addr == requested_addr) {
2449 return requested_addr;
2450 }
2451
2452 if (addr != NULL) {
2453 // mmap() is successful but it fails to reserve at the requested address
2454 anon_munmap(addr, bytes);
2455 }
2456
2457 int i;
2458 for (i = 0; i < max_tries; ++i) {
2459 base[i] = reserve_memory(bytes);
2460
2461 if (base[i] != NULL) {
2462 // Is this the block we wanted?
2463 if (base[i] == requested_addr) {
2464 size[i] = bytes;
2465 break;
2466 }
2467
2468 // Does this overlap the block we wanted? Give back the overlapped
2469 // parts and try again.
2470
2471 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2472 if (top_overlap >= 0 && top_overlap < bytes) {
2473 unmap_memory(base[i], top_overlap);
2474 base[i] += top_overlap;
2475 size[i] = bytes - top_overlap;
2476 } else {
2477 size_t bottom_overlap = base[i] + bytes - requested_addr;
2478 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2479 unmap_memory(requested_addr, bottom_overlap);
2480 size[i] = bytes - bottom_overlap;
2481 } else {
2482 size[i] = bytes;
2483 }
2484 }
2485 }
2486 }
2487
2488 // Give back the unused reserved pieces.
2489
2490 for (int j = 0; j < i; ++j) {
2491 if (base[j] != NULL) {
2492 unmap_memory(base[j], size[j]);
2493 }
2494 }
2495
2496 if (i < max_tries) {
2497 return requested_addr;
2498 } else {
2499 return NULL;
2500 }
2501 }
2502
2503 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2504 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2505 }
2506
2507 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2508 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2509 }
2510
2511 void os::naked_short_sleep(jlong ms) {
2512 struct timespec req;
2513
2514 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2515 req.tv_sec = 0;
2516 if (ms > 0) {
2517 req.tv_nsec = (ms % 1000) * 1000000;
2518 } else {
2519 req.tv_nsec = 1;
2520 }
2521
2522 nanosleep(&req, NULL);
2523
2524 return;
2525 }
2526
2527 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2528 void os::infinite_sleep() {
2529 while (true) { // sleep forever ...
2530 ::sleep(100); // ... 100 seconds at a time
2531 }
2532 }
2533
2534 // Used to convert frequent JVM_Yield() to nops
2535 bool os::dont_yield() {
2536 return DontYieldALot;
2537 }
2538
2539 void os::naked_yield() {
2540 sched_yield();
2541 }
2542
2543 ////////////////////////////////////////////////////////////////////////////////
2544 // thread priority support
2545
2546 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2547 // only supports dynamic priority, static priority must be zero. For real-time
2548 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2549 // However, for large multi-threaded applications, SCHED_RR is not only slower
2550 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2551 // of 5 runs - Sep 2005).
2552 //
2553 // The following code actually changes the niceness of kernel-thread/LWP. It
2554 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2555 // not the entire user process, and user level threads are 1:1 mapped to kernel
2556 // threads. It has always been the case, but could change in the future. For
2557 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2558 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2559
2560 #if !defined(__APPLE__)
2561 int os::java_to_os_priority[CriticalPriority + 1] = {
2562 19, // 0 Entry should never be used
2563
2564 0, // 1 MinPriority
2565 3, // 2
2566 6, // 3
2567
2568 10, // 4
2569 15, // 5 NormPriority
2570 18, // 6
2571
2572 21, // 7
2573 25, // 8
2574 28, // 9 NearMaxPriority
2575
2576 31, // 10 MaxPriority
2577
2578 31 // 11 CriticalPriority
2579 };
2580 #else
2581 // Using Mach high-level priority assignments
2582 int os::java_to_os_priority[CriticalPriority + 1] = {
2583 0, // 0 Entry should never be used (MINPRI_USER)
2584
2585 27, // 1 MinPriority
2586 28, // 2
2587 29, // 3
2588
2589 30, // 4
2590 31, // 5 NormPriority (BASEPRI_DEFAULT)
2591 32, // 6
2592
2593 33, // 7
2594 34, // 8
2595 35, // 9 NearMaxPriority
2596
2597 36, // 10 MaxPriority
2598
2599 36 // 11 CriticalPriority
2600 };
2601 #endif
2602
2603 static int prio_init() {
2604 if (ThreadPriorityPolicy == 1) {
2605 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2606 // if effective uid is not root. Perhaps, a more elegant way of doing
2607 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2608 if (geteuid() != 0) {
2609 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2610 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2611 }
2612 ThreadPriorityPolicy = 0;
2613 }
2614 }
2615 if (UseCriticalJavaThreadPriority) {
2616 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2617 }
2618 return 0;
2619 }
2620
2621 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2622 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2623
2624 #ifdef __OpenBSD__
2625 // OpenBSD pthread_setprio starves low priority threads
2626 return OS_OK;
2627 #elif defined(__FreeBSD__)
2628 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2629 #elif defined(__APPLE__) || defined(__NetBSD__)
2630 struct sched_param sp;
2631 int policy;
2632 pthread_t self = pthread_self();
2633
2634 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2635 return OS_ERR;
2636 }
2637
2638 sp.sched_priority = newpri;
2639 if (pthread_setschedparam(self, policy, &sp) != 0) {
2640 return OS_ERR;
2641 }
2642
2643 return OS_OK;
2644 #else
2645 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2646 return (ret == 0) ? OS_OK : OS_ERR;
2647 #endif
2648 }
2649
2650 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2651 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2652 *priority_ptr = java_to_os_priority[NormPriority];
2653 return OS_OK;
2654 }
2655
2656 errno = 0;
2657 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2658 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2659 #elif defined(__APPLE__) || defined(__NetBSD__)
2660 int policy;
2661 struct sched_param sp;
2662
2663 pthread_getschedparam(pthread_self(), &policy, &sp);
2664 *priority_ptr = sp.sched_priority;
2665 #else
2666 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2667 #endif
2668 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2669 }
2670
2671 // Hint to the underlying OS that a task switch would not be good.
2672 // Void return because it's a hint and can fail.
2673 void os::hint_no_preempt() {}
2674
2675 ////////////////////////////////////////////////////////////////////////////////
2676 // suspend/resume support
2677
2678 // the low-level signal-based suspend/resume support is a remnant from the
2679 // old VM-suspension that used to be for java-suspension, safepoints etc,
2680 // within hotspot. Now there is a single use-case for this:
2681 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2682 // that runs in the watcher thread.
2683 // The remaining code is greatly simplified from the more general suspension
2684 // code that used to be used.
2685 //
2686 // The protocol is quite simple:
2687 // - suspend:
2688 // - sends a signal to the target thread
2689 // - polls the suspend state of the osthread using a yield loop
2690 // - target thread signal handler (SR_handler) sets suspend state
2691 // and blocks in sigsuspend until continued
2692 // - resume:
2693 // - sets target osthread state to continue
2694 // - sends signal to end the sigsuspend loop in the SR_handler
2695 //
2696 // Note that the SR_lock plays no role in this suspend/resume protocol,
2697 // but is checked for NULL in SR_handler as a thread termination indicator.
2698
2699 static void resume_clear_context(OSThread *osthread) {
2700 osthread->set_ucontext(NULL);
2701 osthread->set_siginfo(NULL);
2702 }
2703
2704 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2705 osthread->set_ucontext(context);
2706 osthread->set_siginfo(siginfo);
2707 }
2708
2709 // Handler function invoked when a thread's execution is suspended or
2710 // resumed. We have to be careful that only async-safe functions are
2711 // called here (Note: most pthread functions are not async safe and
2712 // should be avoided.)
2713 //
2714 // Note: sigwait() is a more natural fit than sigsuspend() from an
2715 // interface point of view, but sigwait() prevents the signal hander
2716 // from being run. libpthread would get very confused by not having
2717 // its signal handlers run and prevents sigwait()'s use with the
2718 // mutex granting granting signal.
2719 //
2720 // Currently only ever called on the VMThread or JavaThread
2721 //
2722 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2723 // Save and restore errno to avoid confusing native code with EINTR
2724 // after sigsuspend.
2725 int old_errno = errno;
2726
2727 Thread* thread = Thread::current_or_null_safe();
2728 assert(thread != NULL, "Missing current thread in SR_handler");
2729
2730 // On some systems we have seen signal delivery get "stuck" until the signal
2731 // mask is changed as part of thread termination. Check that the current thread
2732 // has not already terminated (via SR_lock()) - else the following assertion
2733 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2734 // destructor has completed.
2735
2736 if (thread->SR_lock() == NULL) {
2737 return;
2738 }
2739
2740 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2741
2742 OSThread* osthread = thread->osthread();
2743
2744 os::SuspendResume::State current = osthread->sr.state();
2745 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2746 suspend_save_context(osthread, siginfo, context);
2747
2748 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2749 os::SuspendResume::State state = osthread->sr.suspended();
2750 if (state == os::SuspendResume::SR_SUSPENDED) {
2751 sigset_t suspend_set; // signals for sigsuspend()
2752
2753 // get current set of blocked signals and unblock resume signal
2754 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2755 sigdelset(&suspend_set, SR_signum);
2756
2757 sr_semaphore.signal();
2758 // wait here until we are resumed
2759 while (1) {
2760 sigsuspend(&suspend_set);
2761
2762 os::SuspendResume::State result = osthread->sr.running();
2763 if (result == os::SuspendResume::SR_RUNNING) {
2764 sr_semaphore.signal();
2765 break;
2766 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2767 ShouldNotReachHere();
2768 }
2769 }
2770
2771 } else if (state == os::SuspendResume::SR_RUNNING) {
2772 // request was cancelled, continue
2773 } else {
2774 ShouldNotReachHere();
2775 }
2776
2777 resume_clear_context(osthread);
2778 } else if (current == os::SuspendResume::SR_RUNNING) {
2779 // request was cancelled, continue
2780 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2781 // ignore
2782 } else {
2783 // ignore
2784 }
2785
2786 errno = old_errno;
2787 }
2788
2789
2790 static int SR_initialize() {
2791 struct sigaction act;
2792 char *s;
2793 // Get signal number to use for suspend/resume
2794 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2795 int sig = ::strtol(s, 0, 10);
2796 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2797 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2798 SR_signum = sig;
2799 } else {
2800 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2801 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2802 }
2803 }
2804
2805 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2806 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2807
2808 sigemptyset(&SR_sigset);
2809 sigaddset(&SR_sigset, SR_signum);
2810
2811 // Set up signal handler for suspend/resume
2812 act.sa_flags = SA_RESTART|SA_SIGINFO;
2813 act.sa_handler = (void (*)(int)) SR_handler;
2814
2815 // SR_signum is blocked by default.
2816 // 4528190 - We also need to block pthread restart signal (32 on all
2817 // supported Bsd platforms). Note that BsdThreads need to block
2818 // this signal for all threads to work properly. So we don't have
2819 // to use hard-coded signal number when setting up the mask.
2820 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2821
2822 if (sigaction(SR_signum, &act, 0) == -1) {
2823 return -1;
2824 }
2825
2826 // Save signal flag
2827 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2828 return 0;
2829 }
2830
2831 static int sr_notify(OSThread* osthread) {
2832 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2833 assert_status(status == 0, status, "pthread_kill");
2834 return status;
2835 }
2836
2837 // "Randomly" selected value for how long we want to spin
2838 // before bailing out on suspending a thread, also how often
2839 // we send a signal to a thread we want to resume
2840 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2841 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2842
2843 // returns true on success and false on error - really an error is fatal
2844 // but this seems the normal response to library errors
2845 static bool do_suspend(OSThread* osthread) {
2846 assert(osthread->sr.is_running(), "thread should be running");
2847 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2848
2849 // mark as suspended and send signal
2850 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2851 // failed to switch, state wasn't running?
2852 ShouldNotReachHere();
2853 return false;
2854 }
2855
2856 if (sr_notify(osthread) != 0) {
2857 ShouldNotReachHere();
2858 }
2859
2860 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2861 while (true) {
2862 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2863 break;
2864 } else {
2865 // timeout
2866 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2867 if (cancelled == os::SuspendResume::SR_RUNNING) {
2868 return false;
2869 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2870 // make sure that we consume the signal on the semaphore as well
2871 sr_semaphore.wait();
2872 break;
2873 } else {
2874 ShouldNotReachHere();
2875 return false;
2876 }
2877 }
2878 }
2879
2880 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2881 return true;
2882 }
2883
2884 static void do_resume(OSThread* osthread) {
2885 assert(osthread->sr.is_suspended(), "thread should be suspended");
2886 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2887
2888 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2889 // failed to switch to WAKEUP_REQUEST
2890 ShouldNotReachHere();
2891 return;
2892 }
2893
2894 while (true) {
2895 if (sr_notify(osthread) == 0) {
2896 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2897 if (osthread->sr.is_running()) {
2898 return;
2899 }
2900 }
2901 } else {
2902 ShouldNotReachHere();
2903 }
2904 }
2905
2906 guarantee(osthread->sr.is_running(), "Must be running!");
2907 }
2908
2909 ///////////////////////////////////////////////////////////////////////////////////
2910 // signal handling (except suspend/resume)
2911
2912 // This routine may be used by user applications as a "hook" to catch signals.
2913 // The user-defined signal handler must pass unrecognized signals to this
2914 // routine, and if it returns true (non-zero), then the signal handler must
2915 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2916 // routine will never retun false (zero), but instead will execute a VM panic
2917 // routine kill the process.
2918 //
2919 // If this routine returns false, it is OK to call it again. This allows
2920 // the user-defined signal handler to perform checks either before or after
2921 // the VM performs its own checks. Naturally, the user code would be making
2922 // a serious error if it tried to handle an exception (such as a null check
2923 // or breakpoint) that the VM was generating for its own correct operation.
2924 //
2925 // This routine may recognize any of the following kinds of signals:
2926 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2927 // It should be consulted by handlers for any of those signals.
2928 //
2929 // The caller of this routine must pass in the three arguments supplied
2930 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2931 // field of the structure passed to sigaction(). This routine assumes that
2932 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2933 //
2934 // Note that the VM will print warnings if it detects conflicting signal
2935 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2936 //
2937 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2938 void* ucontext,
2939 int abort_if_unrecognized);
2940
2941 void signalHandler(int sig, siginfo_t* info, void* uc) {
2942 assert(info != NULL && uc != NULL, "it must be old kernel");
2943 int orig_errno = errno; // Preserve errno value over signal handler.
2944 JVM_handle_bsd_signal(sig, info, uc, true);
2945 errno = orig_errno;
2946 }
2947
2948
2949 // This boolean allows users to forward their own non-matching signals
2950 // to JVM_handle_bsd_signal, harmlessly.
2951 bool os::Bsd::signal_handlers_are_installed = false;
2952
2953 // For signal-chaining
2954 struct sigaction sigact[NSIG];
2955 uint32_t sigs = 0;
2956 #if (32 < NSIG-1)
2957 #error "Not all signals can be encoded in sigs. Adapt its type!"
2958 #endif
2959 bool os::Bsd::libjsig_is_loaded = false;
2960 typedef struct sigaction *(*get_signal_t)(int);
2961 get_signal_t os::Bsd::get_signal_action = NULL;
2962
2963 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2964 struct sigaction *actp = NULL;
2965
2966 if (libjsig_is_loaded) {
2967 // Retrieve the old signal handler from libjsig
2968 actp = (*get_signal_action)(sig);
2969 }
2970 if (actp == NULL) {
2971 // Retrieve the preinstalled signal handler from jvm
2972 actp = get_preinstalled_handler(sig);
2973 }
2974
2975 return actp;
2976 }
2977
2978 static bool call_chained_handler(struct sigaction *actp, int sig,
2979 siginfo_t *siginfo, void *context) {
2980 // Call the old signal handler
2981 if (actp->sa_handler == SIG_DFL) {
2982 // It's more reasonable to let jvm treat it as an unexpected exception
2983 // instead of taking the default action.
2984 return false;
2985 } else if (actp->sa_handler != SIG_IGN) {
2986 if ((actp->sa_flags & SA_NODEFER) == 0) {
2987 // automaticlly block the signal
2988 sigaddset(&(actp->sa_mask), sig);
2989 }
2990
2991 sa_handler_t hand;
2992 sa_sigaction_t sa;
2993 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2994 // retrieve the chained handler
2995 if (siginfo_flag_set) {
2996 sa = actp->sa_sigaction;
2997 } else {
2998 hand = actp->sa_handler;
2999 }
3000
3001 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3002 actp->sa_handler = SIG_DFL;
3003 }
3004
3005 // try to honor the signal mask
3006 sigset_t oset;
3007 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3008
3009 // call into the chained handler
3010 if (siginfo_flag_set) {
3011 (*sa)(sig, siginfo, context);
3012 } else {
3013 (*hand)(sig);
3014 }
3015
3016 // restore the signal mask
3017 pthread_sigmask(SIG_SETMASK, &oset, 0);
3018 }
3019 // Tell jvm's signal handler the signal is taken care of.
3020 return true;
3021 }
3022
3023 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3024 bool chained = false;
3025 // signal-chaining
3026 if (UseSignalChaining) {
3027 struct sigaction *actp = get_chained_signal_action(sig);
3028 if (actp != NULL) {
3029 chained = call_chained_handler(actp, sig, siginfo, context);
3030 }
3031 }
3032 return chained;
3033 }
3034
3035 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3036 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
3037 return &sigact[sig];
3038 }
3039 return NULL;
3040 }
3041
3042 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3043 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3044 sigact[sig] = oldAct;
3045 sigs |= (uint32_t)1 << (sig-1);
3046 }
3047
3048 // for diagnostic
3049 int sigflags[NSIG];
3050
3051 int os::Bsd::get_our_sigflags(int sig) {
3052 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3053 return sigflags[sig];
3054 }
3055
3056 void os::Bsd::set_our_sigflags(int sig, int flags) {
3057 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3058 if (sig > 0 && sig < NSIG) {
3059 sigflags[sig] = flags;
3060 }
3061 }
3062
3063 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3064 // Check for overwrite.
3065 struct sigaction oldAct;
3066 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3067
3068 void* oldhand = oldAct.sa_sigaction
3069 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3070 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3071 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3072 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3073 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3074 if (AllowUserSignalHandlers || !set_installed) {
3075 // Do not overwrite; user takes responsibility to forward to us.
3076 return;
3077 } else if (UseSignalChaining) {
3078 // save the old handler in jvm
3079 save_preinstalled_handler(sig, oldAct);
3080 // libjsig also interposes the sigaction() call below and saves the
3081 // old sigaction on it own.
3082 } else {
3083 fatal("Encountered unexpected pre-existing sigaction handler "
3084 "%#lx for signal %d.", (long)oldhand, sig);
3085 }
3086 }
3087
3088 struct sigaction sigAct;
3089 sigfillset(&(sigAct.sa_mask));
3090 sigAct.sa_handler = SIG_DFL;
3091 if (!set_installed) {
3092 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3093 } else {
3094 sigAct.sa_sigaction = signalHandler;
3095 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3096 }
3097 #ifdef __APPLE__
3098 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3099 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3100 // if the signal handler declares it will handle it on alternate stack.
3101 // Notice we only declare we will handle it on alt stack, but we are not
3102 // actually going to use real alt stack - this is just a workaround.
3103 // Please see ux_exception.c, method catch_mach_exception_raise for details
3104 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3105 if (sig == SIGSEGV) {
3106 sigAct.sa_flags |= SA_ONSTACK;
3107 }
3108 #endif
3109
3110 // Save flags, which are set by ours
3111 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3112 sigflags[sig] = sigAct.sa_flags;
3113
3114 int ret = sigaction(sig, &sigAct, &oldAct);
3115 assert(ret == 0, "check");
3116
3117 void* oldhand2 = oldAct.sa_sigaction
3118 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3119 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3120 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3121 }
3122
3123 // install signal handlers for signals that HotSpot needs to
3124 // handle in order to support Java-level exception handling.
3125
3126 void os::Bsd::install_signal_handlers() {
3127 if (!signal_handlers_are_installed) {
3128 signal_handlers_are_installed = true;
3129
3130 // signal-chaining
3131 typedef void (*signal_setting_t)();
3132 signal_setting_t begin_signal_setting = NULL;
3133 signal_setting_t end_signal_setting = NULL;
3134 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3135 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3136 if (begin_signal_setting != NULL) {
3137 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3138 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3139 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3140 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3141 libjsig_is_loaded = true;
3142 assert(UseSignalChaining, "should enable signal-chaining");
3143 }
3144 if (libjsig_is_loaded) {
3145 // Tell libjsig jvm is setting signal handlers
3146 (*begin_signal_setting)();
3147 }
3148
3149 set_signal_handler(SIGSEGV, true);
3150 set_signal_handler(SIGPIPE, true);
3151 set_signal_handler(SIGBUS, true);
3152 set_signal_handler(SIGILL, true);
3153 set_signal_handler(SIGFPE, true);
3154 set_signal_handler(SIGXFSZ, true);
3155
3156 #if defined(__APPLE__)
3157 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3158 // signals caught and handled by the JVM. To work around this, we reset the mach task
3159 // signal handler that's placed on our process by CrashReporter. This disables
3160 // CrashReporter-based reporting.
3161 //
3162 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3163 // on caught fatal signals.
3164 //
3165 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3166 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3167 // exception handling, while leaving the standard BSD signal handlers functional.
3168 kern_return_t kr;
3169 kr = task_set_exception_ports(mach_task_self(),
3170 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3171 MACH_PORT_NULL,
3172 EXCEPTION_STATE_IDENTITY,
3173 MACHINE_THREAD_STATE);
3174
3175 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3176 #endif
3177
3178 if (libjsig_is_loaded) {
3179 // Tell libjsig jvm finishes setting signal handlers
3180 (*end_signal_setting)();
3181 }
3182
3183 // We don't activate signal checker if libjsig is in place, we trust ourselves
3184 // and if UserSignalHandler is installed all bets are off
3185 if (CheckJNICalls) {
3186 if (libjsig_is_loaded) {
3187 if (PrintJNIResolving) {
3188 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3189 }
3190 check_signals = false;
3191 }
3192 if (AllowUserSignalHandlers) {
3193 if (PrintJNIResolving) {
3194 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3195 }
3196 check_signals = false;
3197 }
3198 }
3199 }
3200 }
3201
3202
3203 /////
3204 // glibc on Bsd platform uses non-documented flag
3205 // to indicate, that some special sort of signal
3206 // trampoline is used.
3207 // We will never set this flag, and we should
3208 // ignore this flag in our diagnostic
3209 #ifdef SIGNIFICANT_SIGNAL_MASK
3210 #undef SIGNIFICANT_SIGNAL_MASK
3211 #endif
3212 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3213
3214 static const char* get_signal_handler_name(address handler,
3215 char* buf, int buflen) {
3216 int offset;
3217 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3218 if (found) {
3219 // skip directory names
3220 const char *p1, *p2;
3221 p1 = buf;
3222 size_t len = strlen(os::file_separator());
3223 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3224 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3225 } else {
3226 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3227 }
3228 return buf;
3229 }
3230
3231 static void print_signal_handler(outputStream* st, int sig,
3232 char* buf, size_t buflen) {
3233 struct sigaction sa;
3234
3235 sigaction(sig, NULL, &sa);
3236
3237 // See comment for SIGNIFICANT_SIGNAL_MASK define
3238 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3239
3240 st->print("%s: ", os::exception_name(sig, buf, buflen));
3241
3242 address handler = (sa.sa_flags & SA_SIGINFO)
3243 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3244 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3245
3246 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3247 st->print("SIG_DFL");
3248 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3249 st->print("SIG_IGN");
3250 } else {
3251 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3252 }
3253
3254 st->print(", sa_mask[0]=");
3255 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3256
3257 address rh = VMError::get_resetted_sighandler(sig);
3258 // May be, handler was resetted by VMError?
3259 if (rh != NULL) {
3260 handler = rh;
3261 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3262 }
3263
3264 st->print(", sa_flags=");
3265 os::Posix::print_sa_flags(st, sa.sa_flags);
3266
3267 // Check: is it our handler?
3268 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3269 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3270 // It is our signal handler
3271 // check for flags, reset system-used one!
3272 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3273 st->print(
3274 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3275 os::Bsd::get_our_sigflags(sig));
3276 }
3277 }
3278 st->cr();
3279 }
3280
3281
3282 #define DO_SIGNAL_CHECK(sig) \
3283 do { \
3284 if (!sigismember(&check_signal_done, sig)) { \
3285 os::Bsd::check_signal_handler(sig); \
3286 } \
3287 } while (0)
3288
3289 // This method is a periodic task to check for misbehaving JNI applications
3290 // under CheckJNI, we can add any periodic checks here
3291
3292 void os::run_periodic_checks() {
3293
3294 if (check_signals == false) return;
3295
3296 // SEGV and BUS if overridden could potentially prevent
3297 // generation of hs*.log in the event of a crash, debugging
3298 // such a case can be very challenging, so we absolutely
3299 // check the following for a good measure:
3300 DO_SIGNAL_CHECK(SIGSEGV);
3301 DO_SIGNAL_CHECK(SIGILL);
3302 DO_SIGNAL_CHECK(SIGFPE);
3303 DO_SIGNAL_CHECK(SIGBUS);
3304 DO_SIGNAL_CHECK(SIGPIPE);
3305 DO_SIGNAL_CHECK(SIGXFSZ);
3306
3307
3308 // ReduceSignalUsage allows the user to override these handlers
3309 // see comments at the very top and jvm_solaris.h
3310 if (!ReduceSignalUsage) {
3311 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3312 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3313 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3314 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3315 }
3316
3317 DO_SIGNAL_CHECK(SR_signum);
3318 }
3319
3320 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3321
3322 static os_sigaction_t os_sigaction = NULL;
3323
3324 void os::Bsd::check_signal_handler(int sig) {
3325 char buf[O_BUFLEN];
3326 address jvmHandler = NULL;
3327
3328
3329 struct sigaction act;
3330 if (os_sigaction == NULL) {
3331 // only trust the default sigaction, in case it has been interposed
3332 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3333 if (os_sigaction == NULL) return;
3334 }
3335
3336 os_sigaction(sig, (struct sigaction*)NULL, &act);
3337
3338
3339 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3340
3341 address thisHandler = (act.sa_flags & SA_SIGINFO)
3342 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3343 : CAST_FROM_FN_PTR(address, act.sa_handler);
3344
3345
3346 switch (sig) {
3347 case SIGSEGV:
3348 case SIGBUS:
3349 case SIGFPE:
3350 case SIGPIPE:
3351 case SIGILL:
3352 case SIGXFSZ:
3353 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3354 break;
3355
3356 case SHUTDOWN1_SIGNAL:
3357 case SHUTDOWN2_SIGNAL:
3358 case SHUTDOWN3_SIGNAL:
3359 case BREAK_SIGNAL:
3360 jvmHandler = (address)user_handler();
3361 break;
3362
3363 default:
3364 if (sig == SR_signum) {
3365 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3366 } else {
3367 return;
3368 }
3369 break;
3370 }
3371
3372 if (thisHandler != jvmHandler) {
3373 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3374 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3375 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3376 // No need to check this sig any longer
3377 sigaddset(&check_signal_done, sig);
3378 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3379 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3380 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3381 exception_name(sig, buf, O_BUFLEN));
3382 }
3383 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3384 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3385 tty->print("expected:");
3386 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3387 tty->cr();
3388 tty->print(" found:");
3389 os::Posix::print_sa_flags(tty, act.sa_flags);
3390 tty->cr();
3391 // No need to check this sig any longer
3392 sigaddset(&check_signal_done, sig);
3393 }
3394
3395 // Dump all the signal
3396 if (sigismember(&check_signal_done, sig)) {
3397 print_signal_handlers(tty, buf, O_BUFLEN);
3398 }
3399 }
3400
3401 extern void report_error(char* file_name, int line_no, char* title,
3402 char* format, ...);
3403
3404 // this is called _before_ the most of global arguments have been parsed
3405 void os::init(void) {
3406 char dummy; // used to get a guess on initial stack address
3407 // first_hrtime = gethrtime();
3408
3409 // With BsdThreads the JavaMain thread pid (primordial thread)
3410 // is different than the pid of the java launcher thread.
3411 // So, on Bsd, the launcher thread pid is passed to the VM
3412 // via the sun.java.launcher.pid property.
3413 // Use this property instead of getpid() if it was correctly passed.
3414 // See bug 6351349.
3415 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3416
3417 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3418
3419 clock_tics_per_sec = CLK_TCK;
3420
3421 init_random(1234567);
3422
3423 ThreadCritical::initialize();
3424
3425 Bsd::set_page_size(getpagesize());
3426 if (Bsd::page_size() == -1) {
3427 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3428 }
3429 init_page_sizes((size_t) Bsd::page_size());
3430
3431 Bsd::initialize_system_info();
3432
3433 // main_thread points to the aboriginal thread
3434 Bsd::_main_thread = pthread_self();
3435
3436 Bsd::clock_init();
3437 initial_time_count = javaTimeNanos();
3438
3439 #ifdef __APPLE__
3440 // XXXDARWIN
3441 // Work around the unaligned VM callbacks in hotspot's
3442 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3443 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3444 // alignment when doing symbol lookup. To work around this, we force early
3445 // binding of all symbols now, thus binding when alignment is known-good.
3446 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3447 #endif
3448 }
3449
3450 // To install functions for atexit system call
3451 extern "C" {
3452 static void perfMemory_exit_helper() {
3453 perfMemory_exit();
3454 }
3455 }
3456
3457 // this is called _after_ the global arguments have been parsed
3458 jint os::init_2(void) {
3459 // Allocate a single page and mark it as readable for safepoint polling
3460 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3461 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3462
3463 os::set_polling_page(polling_page);
3464 log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3465
3466 if (!UseMembar) {
3467 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3468 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3469 os::set_memory_serialize_page(mem_serialize_page);
3470 log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3471 }
3472
3473 // initialize suspend/resume support - must do this before signal_sets_init()
3474 if (SR_initialize() != 0) {
3475 perror("SR_initialize failed");
3476 return JNI_ERR;
3477 }
3478
3479 Bsd::signal_sets_init();
3480 Bsd::install_signal_handlers();
3481
3482 // Check and sets minimum stack sizes against command line options
3483 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3484 return JNI_ERR;
3485 }
3486
3487 if (MaxFDLimit) {
3488 // set the number of file descriptors to max. print out error
3489 // if getrlimit/setrlimit fails but continue regardless.
3490 struct rlimit nbr_files;
3491 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3492 if (status != 0) {
3493 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3494 } else {
3495 nbr_files.rlim_cur = nbr_files.rlim_max;
3496
3497 #ifdef __APPLE__
3498 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3499 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3500 // be used instead
3501 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3502 #endif
3503
3504 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3505 if (status != 0) {
3506 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3507 }
3508 }
3509 }
3510
3511 // at-exit methods are called in the reverse order of their registration.
3512 // atexit functions are called on return from main or as a result of a
3513 // call to exit(3C). There can be only 32 of these functions registered
3514 // and atexit() does not set errno.
3515
3516 if (PerfAllowAtExitRegistration) {
3517 // only register atexit functions if PerfAllowAtExitRegistration is set.
3518 // atexit functions can be delayed until process exit time, which
3519 // can be problematic for embedded VM situations. Embedded VMs should
3520 // call DestroyJavaVM() to assure that VM resources are released.
3521
3522 // note: perfMemory_exit_helper atexit function may be removed in
3523 // the future if the appropriate cleanup code can be added to the
3524 // VM_Exit VMOperation's doit method.
3525 if (atexit(perfMemory_exit_helper) != 0) {
3526 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3527 }
3528 }
3529
3530 // initialize thread priority policy
3531 prio_init();
3532
3533 #ifdef __APPLE__
3534 // dynamically link to objective c gc registration
3535 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3536 if (handleLibObjc != NULL) {
3537 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3538 }
3539 #endif
3540
3541 return JNI_OK;
3542 }
3543
3544 // Mark the polling page as unreadable
3545 void os::make_polling_page_unreadable(void) {
3546 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3547 fatal("Could not disable polling page");
3548 }
3549 }
3550
3551 // Mark the polling page as readable
3552 void os::make_polling_page_readable(void) {
3553 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3554 fatal("Could not enable polling page");
3555 }
3556 }
3557
3558 int os::active_processor_count() {
3559 return _processor_count;
3560 }
3561
3562 void os::set_native_thread_name(const char *name) {
3563 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3564 // This is only supported in Snow Leopard and beyond
3565 if (name != NULL) {
3566 // Add a "Java: " prefix to the name
3567 char buf[MAXTHREADNAMESIZE];
3568 snprintf(buf, sizeof(buf), "Java: %s", name);
3569 pthread_setname_np(buf);
3570 }
3571 #endif
3572 }
3573
3574 bool os::distribute_processes(uint length, uint* distribution) {
3575 // Not yet implemented.
3576 return false;
3577 }
3578
3579 bool os::bind_to_processor(uint processor_id) {
3580 // Not yet implemented.
3581 return false;
3582 }
3583
3584 void os::SuspendedThreadTask::internal_do_task() {
3585 if (do_suspend(_thread->osthread())) {
3586 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3587 do_task(context);
3588 do_resume(_thread->osthread());
3589 }
3590 }
3591
3592 ///
3593 class PcFetcher : public os::SuspendedThreadTask {
3594 public:
3595 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3596 ExtendedPC result();
3597 protected:
3598 void do_task(const os::SuspendedThreadTaskContext& context);
3599 private:
3600 ExtendedPC _epc;
3601 };
3602
3603 ExtendedPC PcFetcher::result() {
3604 guarantee(is_done(), "task is not done yet.");
3605 return _epc;
3606 }
3607
3608 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3609 Thread* thread = context.thread();
3610 OSThread* osthread = thread->osthread();
3611 if (osthread->ucontext() != NULL) {
3612 _epc = os::Bsd::ucontext_get_pc((const ucontext_t *) context.ucontext());
3613 } else {
3614 // NULL context is unexpected, double-check this is the VMThread
3615 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3616 }
3617 }
3618
3619 // Suspends the target using the signal mechanism and then grabs the PC before
3620 // resuming the target. Used by the flat-profiler only
3621 ExtendedPC os::get_thread_pc(Thread* thread) {
3622 // Make sure that it is called by the watcher for the VMThread
3623 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3624 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3625
3626 PcFetcher fetcher(thread);
3627 fetcher.run();
3628 return fetcher.result();
3629 }
3630
3631 ////////////////////////////////////////////////////////////////////////////////
3632 // debug support
3633
3634 bool os::find(address addr, outputStream* st) {
3635 Dl_info dlinfo;
3636 memset(&dlinfo, 0, sizeof(dlinfo));
3637 if (dladdr(addr, &dlinfo) != 0) {
3638 st->print(PTR_FORMAT ": ", addr);
3639 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3640 st->print("%s+%#x", dlinfo.dli_sname,
3641 addr - (intptr_t)dlinfo.dli_saddr);
3642 } else if (dlinfo.dli_fbase != NULL) {
3643 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3644 } else {
3645 st->print("<absolute address>");
3646 }
3647 if (dlinfo.dli_fname != NULL) {
3648 st->print(" in %s", dlinfo.dli_fname);
3649 }
3650 if (dlinfo.dli_fbase != NULL) {
3651 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3652 }
3653 st->cr();
3654
3655 if (Verbose) {
3656 // decode some bytes around the PC
3657 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3658 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3659 address lowest = (address) dlinfo.dli_sname;
3660 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3661 if (begin < lowest) begin = lowest;
3662 Dl_info dlinfo2;
3663 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3664 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3665 end = (address) dlinfo2.dli_saddr;
3666 }
3667 Disassembler::decode(begin, end, st);
3668 }
3669 return true;
3670 }
3671 return false;
3672 }
3673
3674 ////////////////////////////////////////////////////////////////////////////////
3675 // misc
3676
3677 // This does not do anything on Bsd. This is basically a hook for being
3678 // able to use structured exception handling (thread-local exception filters)
3679 // on, e.g., Win32.
3680 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3681 const methodHandle& method, JavaCallArguments* args,
3682 Thread* thread) {
3683 f(value, method, args, thread);
3684 }
3685
3686 void os::print_statistics() {
3687 }
3688
3689 bool os::message_box(const char* title, const char* message) {
3690 int i;
3691 fdStream err(defaultStream::error_fd());
3692 for (i = 0; i < 78; i++) err.print_raw("=");
3693 err.cr();
3694 err.print_raw_cr(title);
3695 for (i = 0; i < 78; i++) err.print_raw("-");
3696 err.cr();
3697 err.print_raw_cr(message);
3698 for (i = 0; i < 78; i++) err.print_raw("=");
3699 err.cr();
3700
3701 char buf[16];
3702 // Prevent process from exiting upon "read error" without consuming all CPU
3703 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3704
3705 return buf[0] == 'y' || buf[0] == 'Y';
3706 }
3707
3708 int os::stat(const char *path, struct stat *sbuf) {
3709 char pathbuf[MAX_PATH];
3710 if (strlen(path) > MAX_PATH - 1) {
3711 errno = ENAMETOOLONG;
3712 return -1;
3713 }
3714 os::native_path(strcpy(pathbuf, path));
3715 return ::stat(pathbuf, sbuf);
3716 }
3717
3718 static inline struct timespec get_mtime(const char* filename) {
3719 struct stat st;
3720 int ret = os::stat(filename, &st);
3721 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
3722 #ifdef __APPLE__
3723 return st.st_mtimespec;
3724 #else
3725 return st.st_mtim;
3726 #endif
3727 }
3728
3729 int os::compare_file_modified_times(const char* file1, const char* file2) {
3730 struct timespec filetime1 = get_mtime(file1);
3731 struct timespec filetime2 = get_mtime(file2);
3732 int diff = filetime1.tv_sec - filetime2.tv_sec;
3733 if (diff == 0) {
3734 return filetime1.tv_nsec - filetime2.tv_nsec;
3735 }
3736 return diff;
3737 }
3738
3739 // Is a (classpath) directory empty?
3740 bool os::dir_is_empty(const char* path) {
3741 DIR *dir = NULL;
3742 struct dirent *ptr;
3743
3744 dir = opendir(path);
3745 if (dir == NULL) return true;
3746
3747 // Scan the directory
3748 bool result = true;
3749 char buf[sizeof(struct dirent) + MAX_PATH];
3750 while (result && (ptr = ::readdir(dir)) != NULL) {
3751 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3752 result = false;
3753 }
3754 }
3755 closedir(dir);
3756 return result;
3757 }
3758
3759 // This code originates from JDK's sysOpen and open64_w
3760 // from src/solaris/hpi/src/system_md.c
3761
3762 int os::open(const char *path, int oflag, int mode) {
3763 if (strlen(path) > MAX_PATH - 1) {
3764 errno = ENAMETOOLONG;
3765 return -1;
3766 }
3767 int fd;
3768
3769 fd = ::open(path, oflag, mode);
3770 if (fd == -1) return -1;
3771
3772 // If the open succeeded, the file might still be a directory
3773 {
3774 struct stat buf;
3775 int ret = ::fstat(fd, &buf);
3776 int st_mode = buf.st_mode;
3777
3778 if (ret != -1) {
3779 if ((st_mode & S_IFMT) == S_IFDIR) {
3780 errno = EISDIR;
3781 ::close(fd);
3782 return -1;
3783 }
3784 } else {
3785 ::close(fd);
3786 return -1;
3787 }
3788 }
3789
3790 // All file descriptors that are opened in the JVM and not
3791 // specifically destined for a subprocess should have the
3792 // close-on-exec flag set. If we don't set it, then careless 3rd
3793 // party native code might fork and exec without closing all
3794 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3795 // UNIXProcess.c), and this in turn might:
3796 //
3797 // - cause end-of-file to fail to be detected on some file
3798 // descriptors, resulting in mysterious hangs, or
3799 //
3800 // - might cause an fopen in the subprocess to fail on a system
3801 // suffering from bug 1085341.
3802 //
3803 // (Yes, the default setting of the close-on-exec flag is a Unix
3804 // design flaw)
3805 //
3806 // See:
3807 // 1085341: 32-bit stdio routines should support file descriptors >255
3808 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3809 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3810 //
3811 #ifdef FD_CLOEXEC
3812 {
3813 int flags = ::fcntl(fd, F_GETFD);
3814 if (flags != -1) {
3815 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3816 }
3817 }
3818 #endif
3819
3820 return fd;
3821 }
3822
3823
3824 // create binary file, rewriting existing file if required
3825 int os::create_binary_file(const char* path, bool rewrite_existing) {
3826 int oflags = O_WRONLY | O_CREAT;
3827 if (!rewrite_existing) {
3828 oflags |= O_EXCL;
3829 }
3830 return ::open(path, oflags, S_IREAD | S_IWRITE);
3831 }
3832
3833 // return current position of file pointer
3834 jlong os::current_file_offset(int fd) {
3835 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3836 }
3837
3838 // move file pointer to the specified offset
3839 jlong os::seek_to_file_offset(int fd, jlong offset) {
3840 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3841 }
3842
3843 // This code originates from JDK's sysAvailable
3844 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3845
3846 int os::available(int fd, jlong *bytes) {
3847 jlong cur, end;
3848 int mode;
3849 struct stat buf;
3850
3851 if (::fstat(fd, &buf) >= 0) {
3852 mode = buf.st_mode;
3853 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3854 int n;
3855 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3856 *bytes = n;
3857 return 1;
3858 }
3859 }
3860 }
3861 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3862 return 0;
3863 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3864 return 0;
3865 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3866 return 0;
3867 }
3868 *bytes = end - cur;
3869 return 1;
3870 }
3871
3872 // Map a block of memory.
3873 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3874 char *addr, size_t bytes, bool read_only,
3875 bool allow_exec) {
3876 int prot;
3877 int flags;
3878
3879 if (read_only) {
3880 prot = PROT_READ;
3881 flags = MAP_SHARED;
3882 } else {
3883 prot = PROT_READ | PROT_WRITE;
3884 flags = MAP_PRIVATE;
3885 }
3886
3887 if (allow_exec) {
3888 prot |= PROT_EXEC;
3889 }
3890
3891 if (addr != NULL) {
3892 flags |= MAP_FIXED;
3893 }
3894
3895 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3896 fd, file_offset);
3897 if (mapped_address == MAP_FAILED) {
3898 return NULL;
3899 }
3900 return mapped_address;
3901 }
3902
3903
3904 // Remap a block of memory.
3905 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3906 char *addr, size_t bytes, bool read_only,
3907 bool allow_exec) {
3908 // same as map_memory() on this OS
3909 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3910 allow_exec);
3911 }
3912
3913
3914 // Unmap a block of memory.
3915 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3916 return munmap(addr, bytes) == 0;
3917 }
3918
3919 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3920 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3921 // of a thread.
3922 //
3923 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3924 // the fast estimate available on the platform.
3925
3926 jlong os::current_thread_cpu_time() {
3927 #ifdef __APPLE__
3928 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3929 #else
3930 Unimplemented();
3931 return 0;
3932 #endif
3933 }
3934
3935 jlong os::thread_cpu_time(Thread* thread) {
3936 #ifdef __APPLE__
3937 return os::thread_cpu_time(thread, true /* user + sys */);
3938 #else
3939 Unimplemented();
3940 return 0;
3941 #endif
3942 }
3943
3944 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3945 #ifdef __APPLE__
3946 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3947 #else
3948 Unimplemented();
3949 return 0;
3950 #endif
3951 }
3952
3953 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3954 #ifdef __APPLE__
3955 struct thread_basic_info tinfo;
3956 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3957 kern_return_t kr;
3958 thread_t mach_thread;
3959
3960 mach_thread = thread->osthread()->thread_id();
3961 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3962 if (kr != KERN_SUCCESS) {
3963 return -1;
3964 }
3965
3966 if (user_sys_cpu_time) {
3967 jlong nanos;
3968 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3969 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3970 return nanos;
3971 } else {
3972 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3973 }
3974 #else
3975 Unimplemented();
3976 return 0;
3977 #endif
3978 }
3979
3980
3981 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3982 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3983 info_ptr->may_skip_backward = false; // elapsed time not wall time
3984 info_ptr->may_skip_forward = false; // elapsed time not wall time
3985 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3986 }
3987
3988 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3989 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3990 info_ptr->may_skip_backward = false; // elapsed time not wall time
3991 info_ptr->may_skip_forward = false; // elapsed time not wall time
3992 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3993 }
3994
3995 bool os::is_thread_cpu_time_supported() {
3996 #ifdef __APPLE__
3997 return true;
3998 #else
3999 return false;
4000 #endif
4001 }
4002
4003 // System loadavg support. Returns -1 if load average cannot be obtained.
4004 // Bsd doesn't yet have a (official) notion of processor sets,
4005 // so just return the system wide load average.
4006 int os::loadavg(double loadavg[], int nelem) {
4007 return ::getloadavg(loadavg, nelem);
4008 }
4009
4010 void os::pause() {
4011 char filename[MAX_PATH];
4012 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4013 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4014 } else {
4015 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4016 }
4017
4018 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4019 if (fd != -1) {
4020 struct stat buf;
4021 ::close(fd);
4022 while (::stat(filename, &buf) == 0) {
4023 (void)::poll(NULL, 0, 100);
4024 }
4025 } else {
4026 jio_fprintf(stderr,
4027 "Could not open pause file '%s', continuing immediately.\n", filename);
4028 }
4029 }
4030
4031
4032 // Refer to the comments in os_solaris.cpp park-unpark. The next two
4033 // comment paragraphs are worth repeating here:
4034 //
4035 // Assumption:
4036 // Only one parker can exist on an event, which is why we allocate
4037 // them per-thread. Multiple unparkers can coexist.
4038 //
4039 // _Event serves as a restricted-range semaphore.
4040 // -1 : thread is blocked, i.e. there is a waiter
4041 // 0 : neutral: thread is running or ready,
4042 // could have been signaled after a wait started
4043 // 1 : signaled - thread is running or ready
4044 //
4045
4046 // utility to compute the abstime argument to timedwait:
4047 // millis is the relative timeout time
4048 // abstime will be the absolute timeout time
4049 // TODO: replace compute_abstime() with unpackTime()
4050
4051 static struct timespec* compute_abstime(struct timespec* abstime,
4052 jlong millis) {
4053 if (millis < 0) millis = 0;
4054 struct timeval now;
4055 int status = gettimeofday(&now, NULL);
4056 assert(status == 0, "gettimeofday");
4057 jlong seconds = millis / 1000;
4058 millis %= 1000;
4059 if (seconds > 50000000) { // see man cond_timedwait(3T)
4060 seconds = 50000000;
4061 }
4062 abstime->tv_sec = now.tv_sec + seconds;
4063 long usec = now.tv_usec + millis * 1000;
4064 if (usec >= 1000000) {
4065 abstime->tv_sec += 1;
4066 usec -= 1000000;
4067 }
4068 abstime->tv_nsec = usec * 1000;
4069 return abstime;
4070 }
4071
4072 void os::PlatformEvent::park() { // AKA "down()"
4073 // Transitions for _Event:
4074 // -1 => -1 : illegal
4075 // 1 => 0 : pass - return immediately
4076 // 0 => -1 : block; then set _Event to 0 before returning
4077
4078 // Invariant: Only the thread associated with the Event/PlatformEvent
4079 // may call park().
4080 // TODO: assert that _Assoc != NULL or _Assoc == Self
4081 assert(_nParked == 0, "invariant");
4082
4083 int v;
4084 for (;;) {
4085 v = _Event;
4086 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4087 }
4088 guarantee(v >= 0, "invariant");
4089 if (v == 0) {
4090 // Do this the hard way by blocking ...
4091 int status = pthread_mutex_lock(_mutex);
4092 assert_status(status == 0, status, "mutex_lock");
4093 guarantee(_nParked == 0, "invariant");
4094 ++_nParked;
4095 while (_Event < 0) {
4096 status = pthread_cond_wait(_cond, _mutex);
4097 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4098 // Treat this the same as if the wait was interrupted
4099 if (status == ETIMEDOUT) { status = EINTR; }
4100 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4101 }
4102 --_nParked;
4103
4104 _Event = 0;
4105 status = pthread_mutex_unlock(_mutex);
4106 assert_status(status == 0, status, "mutex_unlock");
4107 // Paranoia to ensure our locked and lock-free paths interact
4108 // correctly with each other.
4109 OrderAccess::fence();
4110 }
4111 guarantee(_Event >= 0, "invariant");
4112 }
4113
4114 int os::PlatformEvent::park(jlong millis) {
4115 // Transitions for _Event:
4116 // -1 => -1 : illegal
4117 // 1 => 0 : pass - return immediately
4118 // 0 => -1 : block; then set _Event to 0 before returning
4119
4120 guarantee(_nParked == 0, "invariant");
4121
4122 int v;
4123 for (;;) {
4124 v = _Event;
4125 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4126 }
4127 guarantee(v >= 0, "invariant");
4128 if (v != 0) return OS_OK;
4129
4130 // We do this the hard way, by blocking the thread.
4131 // Consider enforcing a minimum timeout value.
4132 struct timespec abst;
4133 compute_abstime(&abst, millis);
4134
4135 int ret = OS_TIMEOUT;
4136 int status = pthread_mutex_lock(_mutex);
4137 assert_status(status == 0, status, "mutex_lock");
4138 guarantee(_nParked == 0, "invariant");
4139 ++_nParked;
4140
4141 // Object.wait(timo) will return because of
4142 // (a) notification
4143 // (b) timeout
4144 // (c) thread.interrupt
4145 //
4146 // Thread.interrupt and object.notify{All} both call Event::set.
4147 // That is, we treat thread.interrupt as a special case of notification.
4148 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4149 // We assume all ETIME returns are valid.
4150 //
4151 // TODO: properly differentiate simultaneous notify+interrupt.
4152 // In that case, we should propagate the notify to another waiter.
4153
4154 while (_Event < 0) {
4155 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4156 assert_status(status == 0 || status == EINTR ||
4157 status == ETIMEDOUT,
4158 status, "cond_timedwait");
4159 if (!FilterSpuriousWakeups) break; // previous semantics
4160 if (status == ETIMEDOUT) break;
4161 // We consume and ignore EINTR and spurious wakeups.
4162 }
4163 --_nParked;
4164 if (_Event >= 0) {
4165 ret = OS_OK;
4166 }
4167 _Event = 0;
4168 status = pthread_mutex_unlock(_mutex);
4169 assert_status(status == 0, status, "mutex_unlock");
4170 assert(_nParked == 0, "invariant");
4171 // Paranoia to ensure our locked and lock-free paths interact
4172 // correctly with each other.
4173 OrderAccess::fence();
4174 return ret;
4175 }
4176
4177 void os::PlatformEvent::unpark() {
4178 // Transitions for _Event:
4179 // 0 => 1 : just return
4180 // 1 => 1 : just return
4181 // -1 => either 0 or 1; must signal target thread
4182 // That is, we can safely transition _Event from -1 to either
4183 // 0 or 1.
4184 // See also: "Semaphores in Plan 9" by Mullender & Cox
4185 //
4186 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4187 // that it will take two back-to-back park() calls for the owning
4188 // thread to block. This has the benefit of forcing a spurious return
4189 // from the first park() call after an unpark() call which will help
4190 // shake out uses of park() and unpark() without condition variables.
4191
4192 if (Atomic::xchg(1, &_Event) >= 0) return;
4193
4194 // Wait for the thread associated with the event to vacate
4195 int status = pthread_mutex_lock(_mutex);
4196 assert_status(status == 0, status, "mutex_lock");
4197 int AnyWaiters = _nParked;
4198 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4199 status = pthread_mutex_unlock(_mutex);
4200 assert_status(status == 0, status, "mutex_unlock");
4201 if (AnyWaiters != 0) {
4202 // Note that we signal() *after* dropping the lock for "immortal" Events.
4203 // This is safe and avoids a common class of futile wakeups. In rare
4204 // circumstances this can cause a thread to return prematurely from
4205 // cond_{timed}wait() but the spurious wakeup is benign and the victim
4206 // will simply re-test the condition and re-park itself.
4207 // This provides particular benefit if the underlying platform does not
4208 // provide wait morphing.
4209 status = pthread_cond_signal(_cond);
4210 assert_status(status == 0, status, "cond_signal");
4211 }
4212 }
4213
4214
4215 // JSR166
4216 // -------------------------------------------------------
4217
4218 // The solaris and bsd implementations of park/unpark are fairly
4219 // conservative for now, but can be improved. They currently use a
4220 // mutex/condvar pair, plus a a count.
4221 // Park decrements count if > 0, else does a condvar wait. Unpark
4222 // sets count to 1 and signals condvar. Only one thread ever waits
4223 // on the condvar. Contention seen when trying to park implies that someone
4224 // is unparking you, so don't wait. And spurious returns are fine, so there
4225 // is no need to track notifications.
4226
4227 #define MAX_SECS 100000000
4228
4229 // This code is common to bsd and solaris and will be moved to a
4230 // common place in dolphin.
4231 //
4232 // The passed in time value is either a relative time in nanoseconds
4233 // or an absolute time in milliseconds. Either way it has to be unpacked
4234 // into suitable seconds and nanoseconds components and stored in the
4235 // given timespec structure.
4236 // Given time is a 64-bit value and the time_t used in the timespec is only
4237 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4238 // overflow if times way in the future are given. Further on Solaris versions
4239 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4240 // number of seconds, in abstime, is less than current_time + 100,000,000.
4241 // As it will be 28 years before "now + 100000000" will overflow we can
4242 // ignore overflow and just impose a hard-limit on seconds using the value
4243 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4244 // years from "now".
4245
4246 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4247 assert(time > 0, "convertTime");
4248
4249 struct timeval now;
4250 int status = gettimeofday(&now, NULL);
4251 assert(status == 0, "gettimeofday");
4252
4253 time_t max_secs = now.tv_sec + MAX_SECS;
4254
4255 if (isAbsolute) {
4256 jlong secs = time / 1000;
4257 if (secs > max_secs) {
4258 absTime->tv_sec = max_secs;
4259 } else {
4260 absTime->tv_sec = secs;
4261 }
4262 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4263 } else {
4264 jlong secs = time / NANOSECS_PER_SEC;
4265 if (secs >= MAX_SECS) {
4266 absTime->tv_sec = max_secs;
4267 absTime->tv_nsec = 0;
4268 } else {
4269 absTime->tv_sec = now.tv_sec + secs;
4270 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4271 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4272 absTime->tv_nsec -= NANOSECS_PER_SEC;
4273 ++absTime->tv_sec; // note: this must be <= max_secs
4274 }
4275 }
4276 }
4277 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4278 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4279 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4280 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4281 }
4282
4283 void Parker::park(bool isAbsolute, jlong time) {
4284 // Ideally we'd do something useful while spinning, such
4285 // as calling unpackTime().
4286
4287 // Optional fast-path check:
4288 // Return immediately if a permit is available.
4289 // We depend on Atomic::xchg() having full barrier semantics
4290 // since we are doing a lock-free update to _counter.
4291 if (Atomic::xchg(0, &_counter) > 0) return;
4292
4293 Thread* thread = Thread::current();
4294 assert(thread->is_Java_thread(), "Must be JavaThread");
4295 JavaThread *jt = (JavaThread *)thread;
4296
4297 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4298 // Check interrupt before trying to wait
4299 if (Thread::is_interrupted(thread, false)) {
4300 return;
4301 }
4302
4303 // Next, demultiplex/decode time arguments
4304 struct timespec absTime;
4305 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4306 return;
4307 }
4308 if (time > 0) {
4309 unpackTime(&absTime, isAbsolute, time);
4310 }
4311
4312
4313 // Enter safepoint region
4314 // Beware of deadlocks such as 6317397.
4315 // The per-thread Parker:: mutex is a classic leaf-lock.
4316 // In particular a thread must never block on the Threads_lock while
4317 // holding the Parker:: mutex. If safepoints are pending both the
4318 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4319 ThreadBlockInVM tbivm(jt);
4320
4321 // Don't wait if cannot get lock since interference arises from
4322 // unblocking. Also. check interrupt before trying wait
4323 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4324 return;
4325 }
4326
4327 int status;
4328 if (_counter > 0) { // no wait needed
4329 _counter = 0;
4330 status = pthread_mutex_unlock(_mutex);
4331 assert_status(status == 0, status, "invariant");
4332 // Paranoia to ensure our locked and lock-free paths interact
4333 // correctly with each other and Java-level accesses.
4334 OrderAccess::fence();
4335 return;
4336 }
4337
4338 #ifdef ASSERT
4339 // Don't catch signals while blocked; let the running threads have the signals.
4340 // (This allows a debugger to break into the running thread.)
4341 sigset_t oldsigs;
4342 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4343 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4344 #endif
4345
4346 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4347 jt->set_suspend_equivalent();
4348 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4349
4350 if (time == 0) {
4351 status = pthread_cond_wait(_cond, _mutex);
4352 } else {
4353 status = pthread_cond_timedwait(_cond, _mutex, &absTime);
4354 }
4355 assert_status(status == 0 || status == EINTR ||
4356 status == ETIMEDOUT,
4357 status, "cond_timedwait");
4358
4359 #ifdef ASSERT
4360 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4361 #endif
4362
4363 _counter = 0;
4364 status = pthread_mutex_unlock(_mutex);
4365 assert_status(status == 0, status, "invariant");
4366 // Paranoia to ensure our locked and lock-free paths interact
4367 // correctly with each other and Java-level accesses.
4368 OrderAccess::fence();
4369
4370 // If externally suspended while waiting, re-suspend
4371 if (jt->handle_special_suspend_equivalent_condition()) {
4372 jt->java_suspend_self();
4373 }
4374 }
4375
4376 void Parker::unpark() {
4377 int status = pthread_mutex_lock(_mutex);
4378 assert_status(status == 0, status, "invariant");
4379 const int s = _counter;
4380 _counter = 1;
4381 status = pthread_mutex_unlock(_mutex);
4382 assert_status(status == 0, status, "invariant");
4383 if (s < 1) {
4384 status = pthread_cond_signal(_cond);
4385 assert_status(status == 0, status, "invariant");
4386 }
4387 }
4388
4389
4390 // Darwin has no "environ" in a dynamic library.
4391 #ifdef __APPLE__
4392 #include <crt_externs.h>
4393 #define environ (*_NSGetEnviron())
4394 #else
4395 extern char** environ;
4396 #endif
4397
4398 // Run the specified command in a separate process. Return its exit value,
4399 // or -1 on failure (e.g. can't fork a new process).
4400 // Unlike system(), this function can be called from signal handler. It
4401 // doesn't block SIGINT et al.
4402 int os::fork_and_exec(char* cmd) {
4403 const char * argv[4] = {"sh", "-c", cmd, NULL};
4404
4405 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4406 // pthread_atfork handlers and reset pthread library. All we need is a
4407 // separate process to execve. Make a direct syscall to fork process.
4408 // On IA64 there's no fork syscall, we have to use fork() and hope for
4409 // the best...
4410 pid_t pid = fork();
4411
4412 if (pid < 0) {
4413 // fork failed
4414 return -1;
4415
4416 } else if (pid == 0) {
4417 // child process
4418
4419 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4420 // first to kill every thread on the thread list. Because this list is
4421 // not reset by fork() (see notes above), execve() will instead kill
4422 // every thread in the parent process. We know this is the only thread
4423 // in the new process, so make a system call directly.
4424 // IA64 should use normal execve() from glibc to match the glibc fork()
4425 // above.
4426 execve("/bin/sh", (char* const*)argv, environ);
4427
4428 // execve failed
4429 _exit(-1);
4430
4431 } else {
4432 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4433 // care about the actual exit code, for now.
4434
4435 int status;
4436
4437 // Wait for the child process to exit. This returns immediately if
4438 // the child has already exited. */
4439 while (waitpid(pid, &status, 0) < 0) {
4440 switch (errno) {
4441 case ECHILD: return 0;
4442 case EINTR: break;
4443 default: return -1;
4444 }
4445 }
4446
4447 if (WIFEXITED(status)) {
4448 // The child exited normally; get its exit code.
4449 return WEXITSTATUS(status);
4450 } else if (WIFSIGNALED(status)) {
4451 // The child exited because of a signal
4452 // The best value to return is 0x80 + signal number,
4453 // because that is what all Unix shells do, and because
4454 // it allows callers to distinguish between process exit and
4455 // process death by signal.
4456 return 0x80 + WTERMSIG(status);
4457 } else {
4458 // Unknown exit code; pass it through
4459 return status;
4460 }
4461 }
4462 }
4463
4464 // is_headless_jre()
4465 //
4466 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4467 // in order to report if we are running in a headless jre
4468 //
4469 // Since JDK8 xawt/libmawt.so was moved into the same directory
4470 // as libawt.so, and renamed libawt_xawt.so
4471 //
4472 bool os::is_headless_jre() {
4473 #ifdef __APPLE__
4474 // We no longer build headless-only on Mac OS X
4475 return false;
4476 #else
4477 struct stat statbuf;
4478 char buf[MAXPATHLEN];
4479 char libmawtpath[MAXPATHLEN];
4480 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4481 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4482 char *p;
4483
4484 // Get path to libjvm.so
4485 os::jvm_path(buf, sizeof(buf));
4486
4487 // Get rid of libjvm.so
4488 p = strrchr(buf, '/');
4489 if (p == NULL) {
4490 return false;
4491 } else {
4492 *p = '\0';
4493 }
4494
4495 // Get rid of client or server
4496 p = strrchr(buf, '/');
4497 if (p == NULL) {
4498 return false;
4499 } else {
4500 *p = '\0';
4501 }
4502
4503 // check xawt/libmawt.so
4504 strcpy(libmawtpath, buf);
4505 strcat(libmawtpath, xawtstr);
4506 if (::stat(libmawtpath, &statbuf) == 0) return false;
4507
4508 // check libawt_xawt.so
4509 strcpy(libmawtpath, buf);
4510 strcat(libmawtpath, new_xawtstr);
4511 if (::stat(libmawtpath, &statbuf) == 0) return false;
4512
4513 return true;
4514 #endif
4515 }
4516
4517 // Get the default path to the core file
4518 // Returns the length of the string
4519 int os::get_core_path(char* buffer, size_t bufferSize) {
4520 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4521
4522 // Truncate if theoretical string was longer than bufferSize
4523 n = MIN2(n, (int)bufferSize);
4524
4525 return n;
4526 }
4527
4528 #ifndef PRODUCT
4529 void TestReserveMemorySpecial_test() {
4530 // No tests available for this platform
4531 }
4532 #endif
4533
4534 bool os::start_debugging(char *buf, int buflen) {
4535 int len = (int)strlen(buf);
4536 char *p = &buf[len];
4537
4538 jio_snprintf(p, buflen-len,
4539 "\n\n"
4540 "Do you want to debug the problem?\n\n"
4541 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
4542 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
4543 "Otherwise, press RETURN to abort...",
4544 os::current_process_id(), os::current_process_id(),
4545 os::current_thread_id(), os::current_thread_id());
4546
4547 bool yes = os::message_box("Unexpected Error", buf);
4548
4549 if (yes) {
4550 // yes, user asked VM to launch debugger
4551 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
4552 os::current_process_id(), os::current_process_id());
4553
4554 os::fork_and_exec(buf);
4555 yes = false;
4556 }
4557 return yes;
4558 }