1 /*
2 * Copyright (c) 1999, 2015, 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 "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.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.inline.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 "services/attachListener.hpp"
63 #include "services/memTracker.hpp"
64 #include "services/runtimeService.hpp"
65 #include "utilities/decoder.hpp"
66 #include "utilities/defaultStream.hpp"
67 #include "utilities/events.hpp"
68 #include "utilities/growableArray.hpp"
69 #include "utilities/vmError.hpp"
70
71 // put OS-includes here
72 # include <sys/types.h>
73 # include <sys/mman.h>
74 # include <sys/stat.h>
75 # include <sys/select.h>
76 # include <pthread.h>
77 # include <signal.h>
78 # include <errno.h>
79 # include <dlfcn.h>
80 # include <stdio.h>
81 # include <unistd.h>
82 # include <sys/resource.h>
83 # include <pthread.h>
84 # include <sys/stat.h>
85 # include <sys/time.h>
86 # include <sys/times.h>
87 # include <sys/utsname.h>
88 # include <sys/socket.h>
89 # include <sys/wait.h>
90 # include <time.h>
91 # include <pwd.h>
92 # include <poll.h>
93 # include <semaphore.h>
94 # include <fcntl.h>
95 # include <string.h>
96 # include <sys/param.h>
97 # include <sys/sysctl.h>
98 # include <sys/ipc.h>
99 # include <sys/shm.h>
100 #ifndef __APPLE__
101 # include <link.h>
102 #endif
103 # include <stdint.h>
104 # include <inttypes.h>
105 # include <sys/ioctl.h>
106 # include <sys/syscall.h>
107
108 #if defined(__FreeBSD__) || defined(__NetBSD__)
109 #include <elf.h>
110 #endif
111
112 #ifdef __APPLE__
113 #include <mach/mach.h> // semaphore_* API
114 #include <mach-o/dyld.h>
115 #include <sys/proc_info.h>
116 #include <objc/objc-auto.h>
117 #endif
118
119 #ifndef MAP_ANONYMOUS
120 #define MAP_ANONYMOUS MAP_ANON
121 #endif
122
123 #define MAX_PATH (2 * K)
124
125 // for timer info max values which include all bits
126 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
127
128 #define LARGEPAGES_BIT (1 << 6)
129
130 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
131
132 ////////////////////////////////////////////////////////////////////////////////
133 // global variables
134 julong os::Bsd::_physical_memory = 0;
135
136 #ifdef __APPLE__
137 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
138 volatile uint64_t os::Bsd::_max_abstime = 0;
139 #else
140 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
141 #endif
142 pthread_t os::Bsd::_main_thread;
143 int os::Bsd::_page_size = -1;
144
145 static jlong initial_time_count=0;
146
147 static int clock_tics_per_sec = 100;
148
149 // For diagnostics to print a message once. see run_periodic_checks
150 static sigset_t check_signal_done;
151 static bool check_signals = true;
152
153 static pid_t _initial_pid = 0;
154
155 // Signal number used to suspend/resume a thread
156
157 // do not use any signal number less than SIGSEGV, see 4355769
158 static int SR_signum = SIGUSR2;
159 sigset_t SR_sigset;
160
161
162 ////////////////////////////////////////////////////////////////////////////////
163 // utility functions
164
165 static int SR_initialize();
166 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
167
168 julong os::available_memory() {
169 return Bsd::available_memory();
170 }
171
172 // available here means free
173 julong os::Bsd::available_memory() {
174 uint64_t available = physical_memory() >> 2;
175 #ifdef __APPLE__
176 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
177 vm_statistics64_data_t vmstat;
178 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
179 (host_info64_t)&vmstat, &count);
180 assert(kerr == KERN_SUCCESS,
181 "host_statistics64 failed - check mach_host_self() and count");
182 if (kerr == KERN_SUCCESS) {
183 available = vmstat.free_count * os::vm_page_size();
184 }
185 #endif
186 return available;
187 }
188
189 julong os::physical_memory() {
190 return Bsd::physical_memory();
191 }
192
193 // Return true if user is running as root.
194
195 bool os::have_special_privileges() {
196 static bool init = false;
197 static bool privileges = false;
198 if (!init) {
199 privileges = (getuid() != geteuid()) || (getgid() != getegid());
200 init = true;
201 }
202 return privileges;
203 }
204
205
206
207 // Cpu architecture string
208 #if defined(ZERO)
209 static char cpu_arch[] = ZERO_LIBARCH;
210 #elif defined(IA64)
211 static char cpu_arch[] = "ia64";
212 #elif defined(IA32)
213 static char cpu_arch[] = "i386";
214 #elif defined(AMD64)
215 static char cpu_arch[] = "amd64";
216 #elif defined(ARM)
217 static char cpu_arch[] = "arm";
218 #elif defined(PPC32)
219 static char cpu_arch[] = "ppc";
220 #elif defined(SPARC)
221 #ifdef _LP64
222 static char cpu_arch[] = "sparcv9";
223 #else
224 static char cpu_arch[] = "sparc";
225 #endif
226 #else
227 #error Add appropriate cpu_arch setting
228 #endif
229
230 // Compiler variant
231 #ifdef COMPILER2
232 #define COMPILER_VARIANT "server"
233 #else
234 #define COMPILER_VARIANT "client"
235 #endif
236
237
238 void os::Bsd::initialize_system_info() {
239 int mib[2];
240 size_t len;
241 int cpu_val;
242 julong mem_val;
243
244 // get processors count via hw.ncpus sysctl
245 mib[0] = CTL_HW;
246 mib[1] = HW_NCPU;
247 len = sizeof(cpu_val);
248 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
249 assert(len == sizeof(cpu_val), "unexpected data size");
250 set_processor_count(cpu_val);
251 } else {
252 set_processor_count(1); // fallback
253 }
254
255 // get physical memory via hw.memsize sysctl (hw.memsize is used
256 // since it returns a 64 bit value)
257 mib[0] = CTL_HW;
258
259 #if defined (HW_MEMSIZE) // Apple
260 mib[1] = HW_MEMSIZE;
261 #elif defined(HW_PHYSMEM) // Most of BSD
262 mib[1] = HW_PHYSMEM;
263 #elif defined(HW_REALMEM) // Old FreeBSD
264 mib[1] = HW_REALMEM;
265 #else
266 #error No ways to get physmem
267 #endif
268
269 len = sizeof(mem_val);
270 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
271 assert(len == sizeof(mem_val), "unexpected data size");
272 _physical_memory = mem_val;
273 } else {
274 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
275 }
276
277 #ifdef __OpenBSD__
278 {
279 // limit _physical_memory memory view on OpenBSD since
280 // datasize rlimit restricts us anyway.
281 struct rlimit limits;
282 getrlimit(RLIMIT_DATA, &limits);
283 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
284 }
285 #endif
286 }
287
288 #ifdef __APPLE__
289 static const char *get_home() {
290 const char *home_dir = ::getenv("HOME");
291 if ((home_dir == NULL) || (*home_dir == '\0')) {
292 struct passwd *passwd_info = getpwuid(geteuid());
293 if (passwd_info != NULL) {
294 home_dir = passwd_info->pw_dir;
295 }
296 }
297
298 return home_dir;
299 }
300 #endif
301
302 void os::init_system_properties_values() {
303 // The next steps are taken in the product version:
304 //
305 // Obtain the JAVA_HOME value from the location of libjvm.so.
306 // This library should be located at:
307 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
308 //
309 // If "/jre/lib/" appears at the right place in the path, then we
310 // assume libjvm.so is installed in a JDK and we use this path.
311 //
312 // Otherwise exit with message: "Could not create the Java virtual machine."
313 //
314 // The following extra steps are taken in the debugging version:
315 //
316 // If "/jre/lib/" does NOT appear at the right place in the path
317 // instead of exit check for $JAVA_HOME environment variable.
318 //
319 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
320 // then we append a fake suffix "hotspot/libjvm.so" to this path so
321 // it looks like libjvm.so is installed there
322 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
323 //
324 // Otherwise exit.
325 //
326 // Important note: if the location of libjvm.so changes this
327 // code needs to be changed accordingly.
328
329 // See ld(1):
330 // The linker uses the following search paths to locate required
331 // shared libraries:
332 // 1: ...
333 // ...
334 // 7: The default directories, normally /lib and /usr/lib.
335 #ifndef DEFAULT_LIBPATH
336 #define DEFAULT_LIBPATH "/lib:/usr/lib"
337 #endif
338
339 // Base path of extensions installed on the system.
340 #define SYS_EXT_DIR "/usr/java/packages"
341 #define EXTENSIONS_DIR "/lib/ext"
342
343 #ifndef __APPLE__
344
345 // Buffer that fits several sprintfs.
346 // Note that the space for the colon and the trailing null are provided
347 // by the nulls included by the sizeof operator.
348 const size_t bufsize =
349 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
350 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
351 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
352
353 // sysclasspath, java_home, dll_dir
354 {
355 char *pslash;
356 os::jvm_path(buf, bufsize);
357
358 // Found the full path to libjvm.so.
359 // Now cut the path to <java_home>/jre if we can.
360 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
361 pslash = strrchr(buf, '/');
362 if (pslash != NULL) {
363 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
364 }
365 Arguments::set_dll_dir(buf);
366
367 if (pslash != NULL) {
368 pslash = strrchr(buf, '/');
369 if (pslash != NULL) {
370 *pslash = '\0'; // Get rid of /<arch>.
371 pslash = strrchr(buf, '/');
372 if (pslash != NULL) {
373 *pslash = '\0'; // Get rid of /lib.
374 }
375 }
376 }
377 Arguments::set_java_home(buf);
378 set_boot_path('/', ':');
379 }
380
381 // Where to look for native libraries.
382 //
383 // Note: Due to a legacy implementation, most of the library path
384 // is set in the launcher. This was to accomodate linking restrictions
385 // on legacy Bsd implementations (which are no longer supported).
386 // Eventually, all the library path setting will be done here.
387 //
388 // However, to prevent the proliferation of improperly built native
389 // libraries, the new path component /usr/java/packages is added here.
390 // Eventually, all the library path setting will be done here.
391 {
392 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
393 // should always exist (until the legacy problem cited above is
394 // addressed).
395 const char *v = ::getenv("LD_LIBRARY_PATH");
396 const char *v_colon = ":";
397 if (v == NULL) { v = ""; v_colon = ""; }
398 // That's +1 for the colon and +1 for the trailing '\0'.
399 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
400 strlen(v) + 1 +
401 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
402 mtInternal);
403 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
404 Arguments::set_library_path(ld_library_path);
405 FREE_C_HEAP_ARRAY(char, ld_library_path);
406 }
407
408 // Extensions directories.
409 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
410 Arguments::set_ext_dirs(buf);
411
412 FREE_C_HEAP_ARRAY(char, buf);
413
414 #else // __APPLE__
415
416 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
417 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
418
419 const char *user_home_dir = get_home();
420 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
421 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
422 sizeof(SYS_EXTENSIONS_DIRS);
423
424 // Buffer that fits several sprintfs.
425 // Note that the space for the colon and the trailing null are provided
426 // by the nulls included by the sizeof operator.
427 const size_t bufsize =
428 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
429 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
430 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
431
432 // sysclasspath, java_home, dll_dir
433 {
434 char *pslash;
435 os::jvm_path(buf, bufsize);
436
437 // Found the full path to libjvm.so.
438 // Now cut the path to <java_home>/jre if we can.
439 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
440 pslash = strrchr(buf, '/');
441 if (pslash != NULL) {
442 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
443 }
444 Arguments::set_dll_dir(buf);
445
446 if (pslash != NULL) {
447 pslash = strrchr(buf, '/');
448 if (pslash != NULL) {
449 *pslash = '\0'; // Get rid of /lib.
450 }
451 }
452 Arguments::set_java_home(buf);
453 set_boot_path('/', ':');
454 }
455
456 // Where to look for native libraries.
457 //
458 // Note: Due to a legacy implementation, most of the library path
459 // is set in the launcher. This was to accomodate linking restrictions
460 // on legacy Bsd implementations (which are no longer supported).
461 // Eventually, all the library path setting will be done here.
462 //
463 // However, to prevent the proliferation of improperly built native
464 // libraries, the new path component /usr/java/packages is added here.
465 // Eventually, all the library path setting will be done here.
466 {
467 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
468 // should always exist (until the legacy problem cited above is
469 // addressed).
470 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
471 // can specify a directory inside an app wrapper
472 const char *l = ::getenv("JAVA_LIBRARY_PATH");
473 const char *l_colon = ":";
474 if (l == NULL) { l = ""; l_colon = ""; }
475
476 const char *v = ::getenv("DYLD_LIBRARY_PATH");
477 const char *v_colon = ":";
478 if (v == NULL) { v = ""; v_colon = ""; }
479
480 // Apple's Java6 has "." at the beginning of java.library.path.
481 // OpenJDK on Windows has "." at the end of java.library.path.
482 // OpenJDK on Linux and Solaris don't have "." in java.library.path
483 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
484 // "." is appended to the end of java.library.path. Yes, this
485 // could cause a change in behavior, but Apple's Java6 behavior
486 // can be achieved by putting "." at the beginning of the
487 // JAVA_LIBRARY_PATH environment variable.
488 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
489 strlen(v) + 1 + strlen(l) + 1 +
490 system_ext_size + 3,
491 mtInternal);
492 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
493 v, v_colon, l, l_colon, user_home_dir);
494 Arguments::set_library_path(ld_library_path);
495 FREE_C_HEAP_ARRAY(char, ld_library_path);
496 }
497
498 // Extensions directories.
499 //
500 // Note that the space for the colon and the trailing null are provided
501 // by the nulls included by the sizeof operator (so actually one byte more
502 // than necessary is allocated).
503 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
504 user_home_dir, Arguments::get_java_home());
505 Arguments::set_ext_dirs(buf);
506
507 FREE_C_HEAP_ARRAY(char, buf);
508
509 #undef SYS_EXTENSIONS_DIR
510 #undef SYS_EXTENSIONS_DIRS
511
512 #endif // __APPLE__
513
514 #undef SYS_EXT_DIR
515 #undef EXTENSIONS_DIR
516 }
517
518 ////////////////////////////////////////////////////////////////////////////////
519 // breakpoint support
520
521 void os::breakpoint() {
522 BREAKPOINT;
523 }
524
525 extern "C" void breakpoint() {
526 // use debugger to set breakpoint here
527 }
528
529 ////////////////////////////////////////////////////////////////////////////////
530 // signal support
531
532 debug_only(static bool signal_sets_initialized = false);
533 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
534
535 bool os::Bsd::is_sig_ignored(int sig) {
536 struct sigaction oact;
537 sigaction(sig, (struct sigaction*)NULL, &oact);
538 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
539 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
540 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
541 return true;
542 } else {
543 return false;
544 }
545 }
546
547 void os::Bsd::signal_sets_init() {
548 // Should also have an assertion stating we are still single-threaded.
549 assert(!signal_sets_initialized, "Already initialized");
550 // Fill in signals that are necessarily unblocked for all threads in
551 // the VM. Currently, we unblock the following signals:
552 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
553 // by -Xrs (=ReduceSignalUsage));
554 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
555 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
556 // the dispositions or masks wrt these signals.
557 // Programs embedding the VM that want to use the above signals for their
558 // own purposes must, at this time, use the "-Xrs" option to prevent
559 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
560 // (See bug 4345157, and other related bugs).
561 // In reality, though, unblocking these signals is really a nop, since
562 // these signals are not blocked by default.
563 sigemptyset(&unblocked_sigs);
564 sigemptyset(&allowdebug_blocked_sigs);
565 sigaddset(&unblocked_sigs, SIGILL);
566 sigaddset(&unblocked_sigs, SIGSEGV);
567 sigaddset(&unblocked_sigs, SIGBUS);
568 sigaddset(&unblocked_sigs, SIGFPE);
569 sigaddset(&unblocked_sigs, SR_signum);
570
571 if (!ReduceSignalUsage) {
572 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
573 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
574 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
575 }
576 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
577 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
578 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
579 }
580 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
581 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
582 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
583 }
584 }
585 // Fill in signals that are blocked by all but the VM thread.
586 sigemptyset(&vm_sigs);
587 if (!ReduceSignalUsage) {
588 sigaddset(&vm_sigs, BREAK_SIGNAL);
589 }
590 debug_only(signal_sets_initialized = true);
591
592 }
593
594 // These are signals that are unblocked while a thread is running Java.
595 // (For some reason, they get blocked by default.)
596 sigset_t* os::Bsd::unblocked_signals() {
597 assert(signal_sets_initialized, "Not initialized");
598 return &unblocked_sigs;
599 }
600
601 // These are the signals that are blocked while a (non-VM) thread is
602 // running Java. Only the VM thread handles these signals.
603 sigset_t* os::Bsd::vm_signals() {
604 assert(signal_sets_initialized, "Not initialized");
605 return &vm_sigs;
606 }
607
608 // These are signals that are blocked during cond_wait to allow debugger in
609 sigset_t* os::Bsd::allowdebug_blocked_signals() {
610 assert(signal_sets_initialized, "Not initialized");
611 return &allowdebug_blocked_sigs;
612 }
613
614 void os::Bsd::hotspot_sigmask(Thread* thread) {
615
616 //Save caller's signal mask before setting VM signal mask
617 sigset_t caller_sigmask;
618 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
619
620 OSThread* osthread = thread->osthread();
621 osthread->set_caller_sigmask(caller_sigmask);
622
623 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
624
625 if (!ReduceSignalUsage) {
626 if (thread->is_VM_thread()) {
627 // Only the VM thread handles BREAK_SIGNAL ...
628 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
629 } else {
630 // ... all other threads block BREAK_SIGNAL
631 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
632 }
633 }
634 }
635
636
637 //////////////////////////////////////////////////////////////////////////////
638 // create new thread
639
640 #ifdef __APPLE__
641 // library handle for calling objc_registerThreadWithCollector()
642 // without static linking to the libobjc library
643 #define OBJC_LIB "/usr/lib/libobjc.dylib"
644 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
645 typedef void (*objc_registerThreadWithCollector_t)();
646 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
647 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
648 #endif
649
650 #ifdef __APPLE__
651 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
652 // Additional thread_id used to correlate threads in SA
653 thread_identifier_info_data_t m_ident_info;
654 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
655
656 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
657 (thread_info_t) &m_ident_info, &count);
658
659 return m_ident_info.thread_id;
660 }
661 #endif
662
663 // Thread start routine for all newly created threads
664 static void *java_start(Thread *thread) {
665 // Try to randomize the cache line index of hot stack frames.
666 // This helps when threads of the same stack traces evict each other's
667 // cache lines. The threads can be either from the same JVM instance, or
668 // from different JVM instances. The benefit is especially true for
669 // processors with hyperthreading technology.
670 static int counter = 0;
671 int pid = os::current_process_id();
672 alloca(((pid ^ counter++) & 7) * 128);
673
674 ThreadLocalStorage::set_thread(thread);
675
676 OSThread* osthread = thread->osthread();
677 Monitor* sync = osthread->startThread_lock();
678
679 osthread->set_thread_id(os::Bsd::gettid());
680
681 #ifdef __APPLE__
682 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
683 guarantee(unique_thread_id != 0, "unique thread id was not found");
684 osthread->set_unique_thread_id(unique_thread_id);
685 #endif
686 // initialize signal mask for this thread
687 os::Bsd::hotspot_sigmask(thread);
688
689 // initialize floating point control register
690 os::Bsd::init_thread_fpu_state();
691
692 #ifdef __APPLE__
693 // register thread with objc gc
694 if (objc_registerThreadWithCollectorFunction != NULL) {
695 objc_registerThreadWithCollectorFunction();
696 }
697 #endif
698
699 // handshaking with parent thread
700 {
701 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
702
703 // notify parent thread
704 osthread->set_state(INITIALIZED);
705 sync->notify_all();
706
707 // wait until os::start_thread()
708 while (osthread->get_state() == INITIALIZED) {
709 sync->wait(Mutex::_no_safepoint_check_flag);
710 }
711 }
712
713 // call one more level start routine
714 thread->run();
715
716 return 0;
717 }
718
719 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
720 assert(thread->osthread() == NULL, "caller responsible");
721
722 // Allocate the OSThread object
723 OSThread* osthread = new OSThread(NULL, NULL);
724 if (osthread == NULL) {
725 return false;
726 }
727
728 // set the correct thread state
729 osthread->set_thread_type(thr_type);
730
731 // Initial state is ALLOCATED but not INITIALIZED
732 osthread->set_state(ALLOCATED);
733
734 thread->set_osthread(osthread);
735
736 // init thread attributes
737 pthread_attr_t attr;
738 pthread_attr_init(&attr);
739 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
740
741 // stack size
742 if (os::Bsd::supports_variable_stack_size()) {
743 // calculate stack size if it's not specified by caller
744 if (stack_size == 0) {
745 stack_size = os::Bsd::default_stack_size(thr_type);
746
747 switch (thr_type) {
748 case os::java_thread:
749 // Java threads use ThreadStackSize which default value can be
750 // changed with the flag -Xss
751 assert(JavaThread::stack_size_at_create() > 0, "this should be set");
752 stack_size = JavaThread::stack_size_at_create();
753 break;
754 case os::compiler_thread:
755 if (CompilerThreadStackSize > 0) {
756 stack_size = (size_t)(CompilerThreadStackSize * K);
757 break;
758 } // else fall through:
759 // use VMThreadStackSize if CompilerThreadStackSize is not defined
760 case os::vm_thread:
761 case os::pgc_thread:
762 case os::cgc_thread:
763 case os::watcher_thread:
764 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
765 break;
766 }
767 }
768
769 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
770 pthread_attr_setstacksize(&attr, stack_size);
771 } else {
772 // let pthread_create() pick the default value.
773 }
774
775 ThreadState state;
776
777 {
778 pthread_t tid;
779 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
780
781 pthread_attr_destroy(&attr);
782
783 if (ret != 0) {
784 if (PrintMiscellaneous && (Verbose || WizardMode)) {
785 perror("pthread_create()");
786 }
787 // Need to clean up stuff we've allocated so far
788 thread->set_osthread(NULL);
789 delete osthread;
790 return false;
791 }
792
793 // Store pthread info into the OSThread
794 osthread->set_pthread_id(tid);
795
796 // Wait until child thread is either initialized or aborted
797 {
798 Monitor* sync_with_child = osthread->startThread_lock();
799 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
800 while ((state = osthread->get_state()) == ALLOCATED) {
801 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
802 }
803 }
804
805 }
806
807 // Aborted due to thread limit being reached
808 if (state == ZOMBIE) {
809 thread->set_osthread(NULL);
810 delete osthread;
811 return false;
812 }
813
814 // The thread is returned suspended (in state INITIALIZED),
815 // and is started higher up in the call chain
816 assert(state == INITIALIZED, "race condition");
817 return true;
818 }
819
820 /////////////////////////////////////////////////////////////////////////////
821 // attach existing thread
822
823 // bootstrap the main thread
824 bool os::create_main_thread(JavaThread* thread) {
825 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
826 return create_attached_thread(thread);
827 }
828
829 bool os::create_attached_thread(JavaThread* thread) {
830 #ifdef ASSERT
831 thread->verify_not_published();
832 #endif
833
834 // Allocate the OSThread object
835 OSThread* osthread = new OSThread(NULL, NULL);
836
837 if (osthread == NULL) {
838 return false;
839 }
840
841 osthread->set_thread_id(os::Bsd::gettid());
842
843 // Store pthread info into the OSThread
844 #ifdef __APPLE__
845 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
846 guarantee(unique_thread_id != 0, "just checking");
847 osthread->set_unique_thread_id(unique_thread_id);
848 #endif
849 osthread->set_pthread_id(::pthread_self());
850
851 // initialize floating point control register
852 os::Bsd::init_thread_fpu_state();
853
854 // Initial thread state is RUNNABLE
855 osthread->set_state(RUNNABLE);
856
857 thread->set_osthread(osthread);
858
859 // initialize signal mask for this thread
860 // and save the caller's signal mask
861 os::Bsd::hotspot_sigmask(thread);
862
863 return true;
864 }
865
866 void os::pd_start_thread(Thread* thread) {
867 OSThread * osthread = thread->osthread();
868 assert(osthread->get_state() != INITIALIZED, "just checking");
869 Monitor* sync_with_child = osthread->startThread_lock();
870 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
871 sync_with_child->notify();
872 }
873
874 // Free Bsd resources related to the OSThread
875 void os::free_thread(OSThread* osthread) {
876 assert(osthread != NULL, "osthread not set");
877
878 if (Thread::current()->osthread() == osthread) {
879 // Restore caller's signal mask
880 sigset_t sigmask = osthread->caller_sigmask();
881 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
882 }
883
884 delete osthread;
885 }
886
887 //////////////////////////////////////////////////////////////////////////////
888 // thread local storage
889
890 // Restore the thread pointer if the destructor is called. This is in case
891 // someone from JNI code sets up a destructor with pthread_key_create to run
892 // detachCurrentThread on thread death. Unless we restore the thread pointer we
893 // will hang or crash. When detachCurrentThread is called the key will be set
894 // to null and we will not be called again. If detachCurrentThread is never
895 // called we could loop forever depending on the pthread implementation.
896 static void restore_thread_pointer(void* p) {
897 Thread* thread = (Thread*) p;
898 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
899 }
900
901 int os::allocate_thread_local_storage() {
902 pthread_key_t key;
903 int rslt = pthread_key_create(&key, restore_thread_pointer);
904 assert(rslt == 0, "cannot allocate thread local storage");
905 return (int)key;
906 }
907
908 // Note: This is currently not used by VM, as we don't destroy TLS key
909 // on VM exit.
910 void os::free_thread_local_storage(int index) {
911 int rslt = pthread_key_delete((pthread_key_t)index);
912 assert(rslt == 0, "invalid index");
913 }
914
915 void os::thread_local_storage_at_put(int index, void* value) {
916 int rslt = pthread_setspecific((pthread_key_t)index, value);
917 assert(rslt == 0, "pthread_setspecific failed");
918 }
919
920 extern "C" Thread* get_thread() {
921 return ThreadLocalStorage::thread();
922 }
923
924
925 ////////////////////////////////////////////////////////////////////////////////
926 // time support
927
928 // Time since start-up in seconds to a fine granularity.
929 // Used by VMSelfDestructTimer and the MemProfiler.
930 double os::elapsedTime() {
931
932 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
933 }
934
935 jlong os::elapsed_counter() {
936 return javaTimeNanos() - initial_time_count;
937 }
938
939 jlong os::elapsed_frequency() {
940 return NANOSECS_PER_SEC; // nanosecond resolution
941 }
942
943 bool os::supports_vtime() { return true; }
944 bool os::enable_vtime() { return false; }
945 bool os::vtime_enabled() { return false; }
946
947 double os::elapsedVTime() {
948 // better than nothing, but not much
949 return elapsedTime();
950 }
951
952 jlong os::javaTimeMillis() {
953 timeval time;
954 int status = gettimeofday(&time, NULL);
955 assert(status != -1, "bsd error");
956 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
957 }
958
959 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
960 timeval time;
961 int status = gettimeofday(&time, NULL);
962 assert(status != -1, "bsd error");
963 seconds = jlong(time.tv_sec);
964 nanos = jlong(time.tv_usec) * 1000;
965 }
966
967 #ifndef __APPLE__
968 #ifndef CLOCK_MONOTONIC
969 #define CLOCK_MONOTONIC (1)
970 #endif
971 #endif
972
973 #ifdef __APPLE__
974 void os::Bsd::clock_init() {
975 mach_timebase_info(&_timebase_info);
976 }
977 #else
978 void os::Bsd::clock_init() {
979 struct timespec res;
980 struct timespec tp;
981 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
982 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
983 // yes, monotonic clock is supported
984 _clock_gettime = ::clock_gettime;
985 }
986 }
987 #endif
988
989
990
991 #ifdef __APPLE__
992
993 jlong os::javaTimeNanos() {
994 const uint64_t tm = mach_absolute_time();
995 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
996 const uint64_t prev = Bsd::_max_abstime;
997 if (now <= prev) {
998 return prev; // same or retrograde time;
999 }
1000 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
1001 assert(obsv >= prev, "invariant"); // Monotonicity
1002 // If the CAS succeeded then we're done and return "now".
1003 // If the CAS failed and the observed value "obsv" is >= now then
1004 // we should return "obsv". If the CAS failed and now > obsv > prv then
1005 // some other thread raced this thread and installed a new value, in which case
1006 // we could either (a) retry the entire operation, (b) retry trying to install now
1007 // or (c) just return obsv. We use (c). No loop is required although in some cases
1008 // we might discard a higher "now" value in deference to a slightly lower but freshly
1009 // installed obsv value. That's entirely benign -- it admits no new orderings compared
1010 // to (a) or (b) -- and greatly reduces coherence traffic.
1011 // We might also condition (c) on the magnitude of the delta between obsv and now.
1012 // Avoiding excessive CAS operations to hot RW locations is critical.
1013 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1014 return (prev == obsv) ? now : obsv;
1015 }
1016
1017 #else // __APPLE__
1018
1019 jlong os::javaTimeNanos() {
1020 if (os::supports_monotonic_clock()) {
1021 struct timespec tp;
1022 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1023 assert(status == 0, "gettime error");
1024 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1025 return result;
1026 } else {
1027 timeval time;
1028 int status = gettimeofday(&time, NULL);
1029 assert(status != -1, "bsd error");
1030 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1031 return 1000 * usecs;
1032 }
1033 }
1034
1035 #endif // __APPLE__
1036
1037 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1038 if (os::supports_monotonic_clock()) {
1039 info_ptr->max_value = ALL_64_BITS;
1040
1041 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1042 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1043 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1044 } else {
1045 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1046 info_ptr->max_value = ALL_64_BITS;
1047
1048 // gettimeofday is a real time clock so it skips
1049 info_ptr->may_skip_backward = true;
1050 info_ptr->may_skip_forward = true;
1051 }
1052
1053 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1054 }
1055
1056 // Return the real, user, and system times in seconds from an
1057 // arbitrary fixed point in the past.
1058 bool os::getTimesSecs(double* process_real_time,
1059 double* process_user_time,
1060 double* process_system_time) {
1061 struct tms ticks;
1062 clock_t real_ticks = times(&ticks);
1063
1064 if (real_ticks == (clock_t) (-1)) {
1065 return false;
1066 } else {
1067 double ticks_per_second = (double) clock_tics_per_sec;
1068 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1069 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1070 *process_real_time = ((double) real_ticks) / ticks_per_second;
1071
1072 return true;
1073 }
1074 }
1075
1076
1077 char * os::local_time_string(char *buf, size_t buflen) {
1078 struct tm t;
1079 time_t long_time;
1080 time(&long_time);
1081 localtime_r(&long_time, &t);
1082 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1083 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1084 t.tm_hour, t.tm_min, t.tm_sec);
1085 return buf;
1086 }
1087
1088 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1089 return localtime_r(clock, res);
1090 }
1091
1092 ////////////////////////////////////////////////////////////////////////////////
1093 // runtime exit support
1094
1095 // Note: os::shutdown() might be called very early during initialization, or
1096 // called from signal handler. Before adding something to os::shutdown(), make
1097 // sure it is async-safe and can handle partially initialized VM.
1098 void os::shutdown() {
1099
1100 // allow PerfMemory to attempt cleanup of any persistent resources
1101 perfMemory_exit();
1102
1103 // needs to remove object in file system
1104 AttachListener::abort();
1105
1106 // flush buffered output, finish log files
1107 ostream_abort();
1108
1109 // Check for abort hook
1110 abort_hook_t abort_hook = Arguments::abort_hook();
1111 if (abort_hook != NULL) {
1112 abort_hook();
1113 }
1114
1115 }
1116
1117 // Note: os::abort() might be called very early during initialization, or
1118 // called from signal handler. Before adding something to os::abort(), make
1119 // sure it is async-safe and can handle partially initialized VM.
1120 void os::abort(bool dump_core, void* siginfo, void* context) {
1121 os::shutdown();
1122 if (dump_core) {
1123 #ifndef PRODUCT
1124 fdStream out(defaultStream::output_fd());
1125 out.print_raw("Current thread is ");
1126 char buf[16];
1127 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1128 out.print_raw_cr(buf);
1129 out.print_raw_cr("Dumping core ...");
1130 #endif
1131 ::abort(); // dump core
1132 }
1133
1134 ::exit(1);
1135 }
1136
1137 // Die immediately, no exit hook, no abort hook, no cleanup.
1138 void os::die() {
1139 // _exit() on BsdThreads only kills current thread
1140 ::abort();
1141 }
1142
1143 // This method is a copy of JDK's sysGetLastErrorString
1144 // from src/solaris/hpi/src/system_md.c
1145
1146 size_t os::lasterror(char *buf, size_t len) {
1147 if (errno == 0) return 0;
1148
1149 const char *s = ::strerror(errno);
1150 size_t n = ::strlen(s);
1151 if (n >= len) {
1152 n = len - 1;
1153 }
1154 ::strncpy(buf, s, n);
1155 buf[n] = '\0';
1156 return n;
1157 }
1158
1159 // Information of current thread in variety of formats
1160 pid_t os::Bsd::gettid() {
1161 int retval = -1;
1162
1163 #ifdef __APPLE__ //XNU kernel
1164 // despite the fact mach port is actually not a thread id use it
1165 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1166 retval = ::pthread_mach_thread_np(::pthread_self());
1167 guarantee(retval != 0, "just checking");
1168 return retval;
1169
1170 #else
1171 #ifdef __FreeBSD__
1172 retval = syscall(SYS_thr_self);
1173 #else
1174 #ifdef __OpenBSD__
1175 retval = syscall(SYS_getthrid);
1176 #else
1177 #ifdef __NetBSD__
1178 retval = (pid_t) syscall(SYS__lwp_self);
1179 #endif
1180 #endif
1181 #endif
1182 #endif
1183
1184 if (retval == -1) {
1185 return getpid();
1186 }
1187 }
1188
1189 intx os::current_thread_id() {
1190 #ifdef __APPLE__
1191 return (intx)::pthread_mach_thread_np(::pthread_self());
1192 #else
1193 return (intx)::pthread_self();
1194 #endif
1195 }
1196
1197 int os::current_process_id() {
1198
1199 // Under the old bsd thread library, bsd gives each thread
1200 // its own process id. Because of this each thread will return
1201 // a different pid if this method were to return the result
1202 // of getpid(2). Bsd provides no api that returns the pid
1203 // of the launcher thread for the vm. This implementation
1204 // returns a unique pid, the pid of the launcher thread
1205 // that starts the vm 'process'.
1206
1207 // Under the NPTL, getpid() returns the same pid as the
1208 // launcher thread rather than a unique pid per thread.
1209 // Use gettid() if you want the old pre NPTL behaviour.
1210
1211 // if you are looking for the result of a call to getpid() that
1212 // returns a unique pid for the calling thread, then look at the
1213 // OSThread::thread_id() method in osThread_bsd.hpp file
1214
1215 return (int)(_initial_pid ? _initial_pid : getpid());
1216 }
1217
1218 // DLL functions
1219
1220 #define JNI_LIB_PREFIX "lib"
1221 #ifdef __APPLE__
1222 #define JNI_LIB_SUFFIX ".dylib"
1223 #else
1224 #define JNI_LIB_SUFFIX ".so"
1225 #endif
1226
1227 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1228
1229 // This must be hard coded because it's the system's temporary
1230 // directory not the java application's temp directory, ala java.io.tmpdir.
1231 #ifdef __APPLE__
1232 // macosx has a secure per-user temporary directory
1233 char temp_path_storage[PATH_MAX];
1234 const char* os::get_temp_directory() {
1235 static char *temp_path = NULL;
1236 if (temp_path == NULL) {
1237 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1238 if (pathSize == 0 || pathSize > PATH_MAX) {
1239 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1240 }
1241 temp_path = temp_path_storage;
1242 }
1243 return temp_path;
1244 }
1245 #else // __APPLE__
1246 const char* os::get_temp_directory() { return "/tmp"; }
1247 #endif // __APPLE__
1248
1249 static bool file_exists(const char* filename) {
1250 struct stat statbuf;
1251 if (filename == NULL || strlen(filename) == 0) {
1252 return false;
1253 }
1254 return os::stat(filename, &statbuf) == 0;
1255 }
1256
1257 bool os::dll_build_name(char* buffer, size_t buflen,
1258 const char* pname, const char* fname) {
1259 bool retval = false;
1260 // Copied from libhpi
1261 const size_t pnamelen = pname ? strlen(pname) : 0;
1262
1263 // Return error on buffer overflow.
1264 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1265 return retval;
1266 }
1267
1268 if (pnamelen == 0) {
1269 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1270 retval = true;
1271 } else if (strchr(pname, *os::path_separator()) != NULL) {
1272 int n;
1273 char** pelements = split_path(pname, &n);
1274 if (pelements == NULL) {
1275 return false;
1276 }
1277 for (int i = 0; i < n; i++) {
1278 // Really shouldn't be NULL, but check can't hurt
1279 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1280 continue; // skip the empty path values
1281 }
1282 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1283 pelements[i], fname);
1284 if (file_exists(buffer)) {
1285 retval = true;
1286 break;
1287 }
1288 }
1289 // release the storage
1290 for (int i = 0; i < n; i++) {
1291 if (pelements[i] != NULL) {
1292 FREE_C_HEAP_ARRAY(char, pelements[i]);
1293 }
1294 }
1295 if (pelements != NULL) {
1296 FREE_C_HEAP_ARRAY(char*, pelements);
1297 }
1298 } else {
1299 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1300 retval = true;
1301 }
1302 return retval;
1303 }
1304
1305 // check if addr is inside libjvm.so
1306 bool os::address_is_in_vm(address addr) {
1307 static address libjvm_base_addr;
1308 Dl_info dlinfo;
1309
1310 if (libjvm_base_addr == NULL) {
1311 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1312 libjvm_base_addr = (address)dlinfo.dli_fbase;
1313 }
1314 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1315 }
1316
1317 if (dladdr((void *)addr, &dlinfo) != 0) {
1318 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1319 }
1320
1321 return false;
1322 }
1323
1324
1325 #define MACH_MAXSYMLEN 256
1326
1327 bool os::dll_address_to_function_name(address addr, char *buf,
1328 int buflen, int *offset) {
1329 // buf is not optional, but offset is optional
1330 assert(buf != NULL, "sanity check");
1331
1332 Dl_info dlinfo;
1333 char localbuf[MACH_MAXSYMLEN];
1334
1335 if (dladdr((void*)addr, &dlinfo) != 0) {
1336 // see if we have a matching symbol
1337 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1338 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1339 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1340 }
1341 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1342 return true;
1343 }
1344 // no matching symbol so try for just file info
1345 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1346 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1347 buf, buflen, offset, dlinfo.dli_fname)) {
1348 return true;
1349 }
1350 }
1351
1352 // Handle non-dynamic manually:
1353 if (dlinfo.dli_fbase != NULL &&
1354 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1355 if (!Decoder::demangle(localbuf, buf, buflen)) {
1356 jio_snprintf(buf, buflen, "%s", localbuf);
1357 }
1358 return true;
1359 }
1360 }
1361 buf[0] = '\0';
1362 if (offset != NULL) *offset = -1;
1363 return false;
1364 }
1365
1366 // ported from solaris version
1367 bool os::dll_address_to_library_name(address addr, char* buf,
1368 int buflen, int* offset) {
1369 // buf is not optional, but offset is optional
1370 assert(buf != NULL, "sanity check");
1371
1372 Dl_info dlinfo;
1373
1374 if (dladdr((void*)addr, &dlinfo) != 0) {
1375 if (dlinfo.dli_fname != NULL) {
1376 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1377 }
1378 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1379 *offset = addr - (address)dlinfo.dli_fbase;
1380 }
1381 return true;
1382 }
1383
1384 buf[0] = '\0';
1385 if (offset) *offset = -1;
1386 return false;
1387 }
1388
1389 // Loads .dll/.so and
1390 // in case of error it checks if .dll/.so was built for the
1391 // same architecture as Hotspot is running on
1392
1393 #ifdef __APPLE__
1394 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1395 void * result= ::dlopen(filename, RTLD_LAZY);
1396 if (result != NULL) {
1397 // Successful loading
1398 return result;
1399 }
1400
1401 // Read system error message into ebuf
1402 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1403 ebuf[ebuflen-1]='\0';
1404
1405 return NULL;
1406 }
1407 #else
1408 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1409 void * result= ::dlopen(filename, RTLD_LAZY);
1410 if (result != NULL) {
1411 // Successful loading
1412 return result;
1413 }
1414
1415 Elf32_Ehdr elf_head;
1416
1417 // Read system error message into ebuf
1418 // It may or may not be overwritten below
1419 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1420 ebuf[ebuflen-1]='\0';
1421 int diag_msg_max_length=ebuflen-strlen(ebuf);
1422 char* diag_msg_buf=ebuf+strlen(ebuf);
1423
1424 if (diag_msg_max_length==0) {
1425 // No more space in ebuf for additional diagnostics message
1426 return NULL;
1427 }
1428
1429
1430 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1431
1432 if (file_descriptor < 0) {
1433 // Can't open library, report dlerror() message
1434 return NULL;
1435 }
1436
1437 bool failed_to_read_elf_head=
1438 (sizeof(elf_head)!=
1439 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1440
1441 ::close(file_descriptor);
1442 if (failed_to_read_elf_head) {
1443 // file i/o error - report dlerror() msg
1444 return NULL;
1445 }
1446
1447 typedef struct {
1448 Elf32_Half code; // Actual value as defined in elf.h
1449 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1450 char elf_class; // 32 or 64 bit
1451 char endianess; // MSB or LSB
1452 char* name; // String representation
1453 } arch_t;
1454
1455 #ifndef EM_486
1456 #define EM_486 6 /* Intel 80486 */
1457 #endif
1458
1459 #ifndef EM_MIPS_RS3_LE
1460 #define EM_MIPS_RS3_LE 10 /* MIPS */
1461 #endif
1462
1463 #ifndef EM_PPC64
1464 #define EM_PPC64 21 /* PowerPC64 */
1465 #endif
1466
1467 #ifndef EM_S390
1468 #define EM_S390 22 /* IBM System/390 */
1469 #endif
1470
1471 #ifndef EM_IA_64
1472 #define EM_IA_64 50 /* HP/Intel IA-64 */
1473 #endif
1474
1475 #ifndef EM_X86_64
1476 #define EM_X86_64 62 /* AMD x86-64 */
1477 #endif
1478
1479 static const arch_t arch_array[]={
1480 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1481 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1482 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1483 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1484 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1485 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1486 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1487 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1488 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1489 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1490 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1491 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1492 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1493 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1494 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1495 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1496 };
1497
1498 #if (defined IA32)
1499 static Elf32_Half running_arch_code=EM_386;
1500 #elif (defined AMD64)
1501 static Elf32_Half running_arch_code=EM_X86_64;
1502 #elif (defined IA64)
1503 static Elf32_Half running_arch_code=EM_IA_64;
1504 #elif (defined __sparc) && (defined _LP64)
1505 static Elf32_Half running_arch_code=EM_SPARCV9;
1506 #elif (defined __sparc) && (!defined _LP64)
1507 static Elf32_Half running_arch_code=EM_SPARC;
1508 #elif (defined __powerpc64__)
1509 static Elf32_Half running_arch_code=EM_PPC64;
1510 #elif (defined __powerpc__)
1511 static Elf32_Half running_arch_code=EM_PPC;
1512 #elif (defined ARM)
1513 static Elf32_Half running_arch_code=EM_ARM;
1514 #elif (defined S390)
1515 static Elf32_Half running_arch_code=EM_S390;
1516 #elif (defined ALPHA)
1517 static Elf32_Half running_arch_code=EM_ALPHA;
1518 #elif (defined MIPSEL)
1519 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1520 #elif (defined PARISC)
1521 static Elf32_Half running_arch_code=EM_PARISC;
1522 #elif (defined MIPS)
1523 static Elf32_Half running_arch_code=EM_MIPS;
1524 #elif (defined M68K)
1525 static Elf32_Half running_arch_code=EM_68K;
1526 #else
1527 #error Method os::dll_load requires that one of following is defined:\
1528 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1529 #endif
1530
1531 // Identify compatability class for VM's architecture and library's architecture
1532 // Obtain string descriptions for architectures
1533
1534 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1535 int running_arch_index=-1;
1536
1537 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1538 if (running_arch_code == arch_array[i].code) {
1539 running_arch_index = i;
1540 }
1541 if (lib_arch.code == arch_array[i].code) {
1542 lib_arch.compat_class = arch_array[i].compat_class;
1543 lib_arch.name = arch_array[i].name;
1544 }
1545 }
1546
1547 assert(running_arch_index != -1,
1548 "Didn't find running architecture code (running_arch_code) in arch_array");
1549 if (running_arch_index == -1) {
1550 // Even though running architecture detection failed
1551 // we may still continue with reporting dlerror() message
1552 return NULL;
1553 }
1554
1555 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1556 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1557 return NULL;
1558 }
1559
1560 #ifndef S390
1561 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1562 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1563 return NULL;
1564 }
1565 #endif // !S390
1566
1567 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1568 if (lib_arch.name!=NULL) {
1569 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1570 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1571 lib_arch.name, arch_array[running_arch_index].name);
1572 } else {
1573 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1574 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1575 lib_arch.code,
1576 arch_array[running_arch_index].name);
1577 }
1578 }
1579
1580 return NULL;
1581 }
1582 #endif // !__APPLE__
1583
1584 void* os::get_default_process_handle() {
1585 #ifdef __APPLE__
1586 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1587 // to avoid finding unexpected symbols on second (or later)
1588 // loads of a library.
1589 return (void*)::dlopen(NULL, RTLD_FIRST);
1590 #else
1591 return (void*)::dlopen(NULL, RTLD_LAZY);
1592 #endif
1593 }
1594
1595 // XXX: Do we need a lock around this as per Linux?
1596 void* os::dll_lookup(void* handle, const char* name) {
1597 return dlsym(handle, name);
1598 }
1599
1600
1601 static bool _print_ascii_file(const char* filename, outputStream* st) {
1602 int fd = ::open(filename, O_RDONLY);
1603 if (fd == -1) {
1604 return false;
1605 }
1606
1607 char buf[32];
1608 int bytes;
1609 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1610 st->print_raw(buf, bytes);
1611 }
1612
1613 ::close(fd);
1614
1615 return true;
1616 }
1617
1618 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1619 outputStream * out = (outputStream *) param;
1620 out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1621 return 0;
1622 }
1623
1624 void os::print_dll_info(outputStream *st) {
1625 st->print_cr("Dynamic libraries:");
1626 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1627 st->print_cr("Error: Cannot print dynamic libraries.");
1628 }
1629 }
1630
1631 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1632 #ifdef RTLD_DI_LINKMAP
1633 Dl_info dli;
1634 void *handle;
1635 Link_map *map;
1636 Link_map *p;
1637
1638 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1639 dli.dli_fname == NULL) {
1640 return 1;
1641 }
1642 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1643 if (handle == NULL) {
1644 return 1;
1645 }
1646 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1647 if (map == NULL) {
1648 dlclose(handle);
1649 return 1;
1650 }
1651
1652 while (map->l_prev != NULL)
1653 map = map->l_prev;
1654
1655 while (map != NULL) {
1656 // Value for top_address is returned as 0 since we don't have any information about module size
1657 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1658 dlclose(handle);
1659 return 1;
1660 }
1661 map = map->l_next;
1662 }
1663
1664 dlclose(handle);
1665 #elif defined(__APPLE__)
1666 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1667 // Value for top_address is returned as 0 since we don't have any information about module size
1668 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1669 return 1;
1670 }
1671 }
1672 return 0;
1673 #else
1674 return 1;
1675 #endif
1676 }
1677
1678 void os::print_os_info_brief(outputStream* st) {
1679 st->print("Bsd");
1680
1681 os::Posix::print_uname_info(st);
1682 }
1683
1684 void os::print_os_info(outputStream* st) {
1685 st->print("OS:");
1686 st->print("Bsd");
1687
1688 os::Posix::print_uname_info(st);
1689
1690 os::Posix::print_rlimit_info(st);
1691
1692 os::Posix::print_load_average(st);
1693 }
1694
1695 void os::pd_print_cpu_info(outputStream* st) {
1696 // Nothing to do for now.
1697 }
1698
1699 void os::print_memory_info(outputStream* st) {
1700
1701 st->print("Memory:");
1702 st->print(" %dk page", os::vm_page_size()>>10);
1703
1704 st->print(", physical " UINT64_FORMAT "k",
1705 os::physical_memory() >> 10);
1706 st->print("(" UINT64_FORMAT "k free)",
1707 os::available_memory() >> 10);
1708 st->cr();
1709
1710 // meminfo
1711 st->print("\n/proc/meminfo:\n");
1712 _print_ascii_file("/proc/meminfo", st);
1713 st->cr();
1714 }
1715
1716 void os::print_siginfo(outputStream* st, void* siginfo) {
1717 const siginfo_t* si = (const siginfo_t*)siginfo;
1718
1719 os::Posix::print_siginfo_brief(st, si);
1720
1721 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1722 UseSharedSpaces) {
1723 FileMapInfo* mapinfo = FileMapInfo::current_info();
1724 if (mapinfo->is_in_shared_space(si->si_addr)) {
1725 st->print("\n\nError accessing class data sharing archive." \
1726 " Mapped file inaccessible during execution, " \
1727 " possible disk/network problem.");
1728 }
1729 }
1730 st->cr();
1731 }
1732
1733
1734 static void print_signal_handler(outputStream* st, int sig,
1735 char* buf, size_t buflen);
1736
1737 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1738 st->print_cr("Signal Handlers:");
1739 print_signal_handler(st, SIGSEGV, buf, buflen);
1740 print_signal_handler(st, SIGBUS , buf, buflen);
1741 print_signal_handler(st, SIGFPE , buf, buflen);
1742 print_signal_handler(st, SIGPIPE, buf, buflen);
1743 print_signal_handler(st, SIGXFSZ, buf, buflen);
1744 print_signal_handler(st, SIGILL , buf, buflen);
1745 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1746 print_signal_handler(st, SR_signum, buf, buflen);
1747 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1748 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1749 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1750 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1751 }
1752
1753 static char saved_jvm_path[MAXPATHLEN] = {0};
1754
1755 // Find the full path to the current module, libjvm
1756 void os::jvm_path(char *buf, jint buflen) {
1757 // Error checking.
1758 if (buflen < MAXPATHLEN) {
1759 assert(false, "must use a large-enough buffer");
1760 buf[0] = '\0';
1761 return;
1762 }
1763 // Lazy resolve the path to current module.
1764 if (saved_jvm_path[0] != 0) {
1765 strcpy(buf, saved_jvm_path);
1766 return;
1767 }
1768
1769 char dli_fname[MAXPATHLEN];
1770 bool ret = dll_address_to_library_name(
1771 CAST_FROM_FN_PTR(address, os::jvm_path),
1772 dli_fname, sizeof(dli_fname), NULL);
1773 assert(ret, "cannot locate libjvm");
1774 char *rp = NULL;
1775 if (ret && dli_fname[0] != '\0') {
1776 rp = realpath(dli_fname, buf);
1777 }
1778 if (rp == NULL) {
1779 return;
1780 }
1781
1782 if (Arguments::sun_java_launcher_is_altjvm()) {
1783 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1784 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1785 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1786 // appears at the right place in the string, then assume we are
1787 // installed in a JDK and we're done. Otherwise, check for a
1788 // JAVA_HOME environment variable and construct a path to the JVM
1789 // being overridden.
1790
1791 const char *p = buf + strlen(buf) - 1;
1792 for (int count = 0; p > buf && count < 5; ++count) {
1793 for (--p; p > buf && *p != '/'; --p)
1794 /* empty */ ;
1795 }
1796
1797 if (strncmp(p, "/jre/lib/", 9) != 0) {
1798 // Look for JAVA_HOME in the environment.
1799 char* java_home_var = ::getenv("JAVA_HOME");
1800 if (java_home_var != NULL && java_home_var[0] != 0) {
1801 char* jrelib_p;
1802 int len;
1803
1804 // Check the current module name "libjvm"
1805 p = strrchr(buf, '/');
1806 assert(strstr(p, "/libjvm") == p, "invalid library name");
1807
1808 rp = realpath(java_home_var, buf);
1809 if (rp == NULL) {
1810 return;
1811 }
1812
1813 // determine if this is a legacy image or modules image
1814 // modules image doesn't have "jre" subdirectory
1815 len = strlen(buf);
1816 assert(len < buflen, "Ran out of buffer space");
1817 jrelib_p = buf + len;
1818
1819 // Add the appropriate library subdir
1820 snprintf(jrelib_p, buflen-len, "/jre/lib");
1821 if (0 != access(buf, F_OK)) {
1822 snprintf(jrelib_p, buflen-len, "/lib");
1823 }
1824
1825 // Add the appropriate client or server subdir
1826 len = strlen(buf);
1827 jrelib_p = buf + len;
1828 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1829 if (0 != access(buf, F_OK)) {
1830 snprintf(jrelib_p, buflen-len, "%s", "");
1831 }
1832
1833 // If the path exists within JAVA_HOME, add the JVM library name
1834 // to complete the path to JVM being overridden. Otherwise fallback
1835 // to the path to the current library.
1836 if (0 == access(buf, F_OK)) {
1837 // Use current module name "libjvm"
1838 len = strlen(buf);
1839 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1840 } else {
1841 // Fall back to path of current library
1842 rp = realpath(dli_fname, buf);
1843 if (rp == NULL) {
1844 return;
1845 }
1846 }
1847 }
1848 }
1849 }
1850
1851 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1852 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1853 }
1854
1855 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1856 // no prefix required, not even "_"
1857 }
1858
1859 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1860 // no suffix required
1861 }
1862
1863 ////////////////////////////////////////////////////////////////////////////////
1864 // sun.misc.Signal support
1865
1866 static volatile jint sigint_count = 0;
1867
1868 static void UserHandler(int sig, void *siginfo, void *context) {
1869 // 4511530 - sem_post is serialized and handled by the manager thread. When
1870 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1871 // don't want to flood the manager thread with sem_post requests.
1872 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1873 return;
1874 }
1875
1876 // Ctrl-C is pressed during error reporting, likely because the error
1877 // handler fails to abort. Let VM die immediately.
1878 if (sig == SIGINT && is_error_reported()) {
1879 os::die();
1880 }
1881
1882 os::signal_notify(sig);
1883 }
1884
1885 void* os::user_handler() {
1886 return CAST_FROM_FN_PTR(void*, UserHandler);
1887 }
1888
1889 extern "C" {
1890 typedef void (*sa_handler_t)(int);
1891 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1892 }
1893
1894 void* os::signal(int signal_number, void* handler) {
1895 struct sigaction sigAct, oldSigAct;
1896
1897 sigfillset(&(sigAct.sa_mask));
1898 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1899 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1900
1901 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1902 // -1 means registration failed
1903 return (void *)-1;
1904 }
1905
1906 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1907 }
1908
1909 void os::signal_raise(int signal_number) {
1910 ::raise(signal_number);
1911 }
1912
1913 // The following code is moved from os.cpp for making this
1914 // code platform specific, which it is by its very nature.
1915
1916 // Will be modified when max signal is changed to be dynamic
1917 int os::sigexitnum_pd() {
1918 return NSIG;
1919 }
1920
1921 // a counter for each possible signal value
1922 static volatile jint pending_signals[NSIG+1] = { 0 };
1923
1924 // Bsd(POSIX) specific hand shaking semaphore.
1925 #ifdef __APPLE__
1926 typedef semaphore_t os_semaphore_t;
1927
1928 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1929 #define SEM_WAIT(sem) semaphore_wait(sem)
1930 #define SEM_POST(sem) semaphore_signal(sem)
1931 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1932 #else
1933 typedef sem_t os_semaphore_t;
1934
1935 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1936 #define SEM_WAIT(sem) sem_wait(&sem)
1937 #define SEM_POST(sem) sem_post(&sem)
1938 #define SEM_DESTROY(sem) sem_destroy(&sem)
1939 #endif
1940
1941 class Semaphore : public StackObj {
1942 public:
1943 Semaphore();
1944 ~Semaphore();
1945 void signal();
1946 void wait();
1947 bool trywait();
1948 bool timedwait(unsigned int sec, int nsec);
1949 private:
1950 jlong currenttime() const;
1951 os_semaphore_t _semaphore;
1952 };
1953
1954 Semaphore::Semaphore() : _semaphore(0) {
1955 SEM_INIT(_semaphore, 0);
1956 }
1957
1958 Semaphore::~Semaphore() {
1959 SEM_DESTROY(_semaphore);
1960 }
1961
1962 void Semaphore::signal() {
1963 SEM_POST(_semaphore);
1964 }
1965
1966 void Semaphore::wait() {
1967 SEM_WAIT(_semaphore);
1968 }
1969
1970 jlong Semaphore::currenttime() const {
1971 struct timeval tv;
1972 gettimeofday(&tv, NULL);
1973 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1974 }
1975
1976 #ifdef __APPLE__
1977 bool Semaphore::trywait() {
1978 return timedwait(0, 0);
1979 }
1980
1981 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1982 kern_return_t kr = KERN_ABORTED;
1983 mach_timespec_t waitspec;
1984 waitspec.tv_sec = sec;
1985 waitspec.tv_nsec = nsec;
1986
1987 jlong starttime = currenttime();
1988
1989 kr = semaphore_timedwait(_semaphore, waitspec);
1990 while (kr == KERN_ABORTED) {
1991 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1992
1993 jlong current = currenttime();
1994 jlong passedtime = current - starttime;
1995
1996 if (passedtime >= totalwait) {
1997 waitspec.tv_sec = 0;
1998 waitspec.tv_nsec = 0;
1999 } else {
2000 jlong waittime = totalwait - (current - starttime);
2001 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2002 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2003 }
2004
2005 kr = semaphore_timedwait(_semaphore, waitspec);
2006 }
2007
2008 return kr == KERN_SUCCESS;
2009 }
2010
2011 #else
2012
2013 bool Semaphore::trywait() {
2014 return sem_trywait(&_semaphore) == 0;
2015 }
2016
2017 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2018 struct timespec ts;
2019 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2020
2021 while (1) {
2022 int result = sem_timedwait(&_semaphore, &ts);
2023 if (result == 0) {
2024 return true;
2025 } else if (errno == EINTR) {
2026 continue;
2027 } else if (errno == ETIMEDOUT) {
2028 return false;
2029 } else {
2030 return false;
2031 }
2032 }
2033 }
2034
2035 #endif // __APPLE__
2036
2037 static os_semaphore_t sig_sem;
2038 static Semaphore sr_semaphore;
2039
2040 void os::signal_init_pd() {
2041 // Initialize signal structures
2042 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2043
2044 // Initialize signal semaphore
2045 ::SEM_INIT(sig_sem, 0);
2046 }
2047
2048 void os::signal_notify(int sig) {
2049 Atomic::inc(&pending_signals[sig]);
2050 ::SEM_POST(sig_sem);
2051 }
2052
2053 static int check_pending_signals(bool wait) {
2054 Atomic::store(0, &sigint_count);
2055 for (;;) {
2056 for (int i = 0; i < NSIG + 1; i++) {
2057 jint n = pending_signals[i];
2058 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2059 return i;
2060 }
2061 }
2062 if (!wait) {
2063 return -1;
2064 }
2065 JavaThread *thread = JavaThread::current();
2066 ThreadBlockInVM tbivm(thread);
2067
2068 bool threadIsSuspended;
2069 do {
2070 thread->set_suspend_equivalent();
2071 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2072 ::SEM_WAIT(sig_sem);
2073
2074 // were we externally suspended while we were waiting?
2075 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2076 if (threadIsSuspended) {
2077 // The semaphore has been incremented, but while we were waiting
2078 // another thread suspended us. We don't want to continue running
2079 // while suspended because that would surprise the thread that
2080 // suspended us.
2081 ::SEM_POST(sig_sem);
2082
2083 thread->java_suspend_self();
2084 }
2085 } while (threadIsSuspended);
2086 }
2087 }
2088
2089 int os::signal_lookup() {
2090 return check_pending_signals(false);
2091 }
2092
2093 int os::signal_wait() {
2094 return check_pending_signals(true);
2095 }
2096
2097 ////////////////////////////////////////////////////////////////////////////////
2098 // Virtual Memory
2099
2100 int os::vm_page_size() {
2101 // Seems redundant as all get out
2102 assert(os::Bsd::page_size() != -1, "must call os::init");
2103 return os::Bsd::page_size();
2104 }
2105
2106 // Solaris allocates memory by pages.
2107 int os::vm_allocation_granularity() {
2108 assert(os::Bsd::page_size() != -1, "must call os::init");
2109 return os::Bsd::page_size();
2110 }
2111
2112 // Rationale behind this function:
2113 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2114 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2115 // samples for JITted code. Here we create private executable mapping over the code cache
2116 // and then we can use standard (well, almost, as mapping can change) way to provide
2117 // info for the reporting script by storing timestamp and location of symbol
2118 void bsd_wrap_code(char* base, size_t size) {
2119 static volatile jint cnt = 0;
2120
2121 if (!UseOprofile) {
2122 return;
2123 }
2124
2125 char buf[PATH_MAX + 1];
2126 int num = Atomic::add(1, &cnt);
2127
2128 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2129 os::get_temp_directory(), os::current_process_id(), num);
2130 unlink(buf);
2131
2132 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2133
2134 if (fd != -1) {
2135 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2136 if (rv != (off_t)-1) {
2137 if (::write(fd, "", 1) == 1) {
2138 mmap(base, size,
2139 PROT_READ|PROT_WRITE|PROT_EXEC,
2140 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2141 }
2142 }
2143 ::close(fd);
2144 unlink(buf);
2145 }
2146 }
2147
2148 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2149 int err) {
2150 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2151 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2152 strerror(err), err);
2153 }
2154
2155 // NOTE: Bsd kernel does not really reserve the pages for us.
2156 // All it does is to check if there are enough free pages
2157 // left at the time of mmap(). This could be a potential
2158 // problem.
2159 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2160 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2161 #ifdef __OpenBSD__
2162 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2163 if (::mprotect(addr, size, prot) == 0) {
2164 return true;
2165 }
2166 #else
2167 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2168 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2169 if (res != (uintptr_t) MAP_FAILED) {
2170 return true;
2171 }
2172 #endif
2173
2174 // Warn about any commit errors we see in non-product builds just
2175 // in case mmap() doesn't work as described on the man page.
2176 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2177
2178 return false;
2179 }
2180
2181 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2182 bool exec) {
2183 // alignment_hint is ignored on this OS
2184 return pd_commit_memory(addr, size, exec);
2185 }
2186
2187 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2188 const char* mesg) {
2189 assert(mesg != NULL, "mesg must be specified");
2190 if (!pd_commit_memory(addr, size, exec)) {
2191 // add extra info in product mode for vm_exit_out_of_memory():
2192 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2193 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2194 }
2195 }
2196
2197 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2198 size_t alignment_hint, bool exec,
2199 const char* mesg) {
2200 // alignment_hint is ignored on this OS
2201 pd_commit_memory_or_exit(addr, size, exec, mesg);
2202 }
2203
2204 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2205 }
2206
2207 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2208 ::madvise(addr, bytes, MADV_DONTNEED);
2209 }
2210
2211 void os::numa_make_global(char *addr, size_t bytes) {
2212 }
2213
2214 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2215 }
2216
2217 bool os::numa_topology_changed() { return false; }
2218
2219 size_t os::numa_get_groups_num() {
2220 return 1;
2221 }
2222
2223 int os::numa_get_group_id() {
2224 return 0;
2225 }
2226
2227 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2228 if (size > 0) {
2229 ids[0] = 0;
2230 return 1;
2231 }
2232 return 0;
2233 }
2234
2235 bool os::get_page_info(char *start, page_info* info) {
2236 return false;
2237 }
2238
2239 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2240 return end;
2241 }
2242
2243
2244 bool os::pd_uncommit_memory(char* addr, size_t size) {
2245 #ifdef __OpenBSD__
2246 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2247 return ::mprotect(addr, size, PROT_NONE) == 0;
2248 #else
2249 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2250 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2251 return res != (uintptr_t) MAP_FAILED;
2252 #endif
2253 }
2254
2255 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2256 return os::commit_memory(addr, size, !ExecMem);
2257 }
2258
2259 // If this is a growable mapping, remove the guard pages entirely by
2260 // munmap()ping them. If not, just call uncommit_memory().
2261 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2262 return os::uncommit_memory(addr, size);
2263 }
2264
2265 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2266 // at 'requested_addr'. If there are existing memory mappings at the same
2267 // location, however, they will be overwritten. If 'fixed' is false,
2268 // 'requested_addr' is only treated as a hint, the return value may or
2269 // may not start from the requested address. Unlike Bsd mmap(), this
2270 // function returns NULL to indicate failure.
2271 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2272 char * addr;
2273 int flags;
2274
2275 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2276 if (fixed) {
2277 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2278 flags |= MAP_FIXED;
2279 }
2280
2281 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2282 // touch an uncommitted page. Otherwise, the read/write might
2283 // succeed if we have enough swap space to back the physical page.
2284 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2285 flags, -1, 0);
2286
2287 return addr == MAP_FAILED ? NULL : addr;
2288 }
2289
2290 static int anon_munmap(char * addr, size_t size) {
2291 return ::munmap(addr, size) == 0;
2292 }
2293
2294 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2295 size_t alignment_hint) {
2296 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2297 }
2298
2299 bool os::pd_release_memory(char* addr, size_t size) {
2300 return anon_munmap(addr, size);
2301 }
2302
2303 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2304 // Bsd wants the mprotect address argument to be page aligned.
2305 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2306
2307 // According to SUSv3, mprotect() should only be used with mappings
2308 // established by mmap(), and mmap() always maps whole pages. Unaligned
2309 // 'addr' likely indicates problem in the VM (e.g. trying to change
2310 // protection of malloc'ed or statically allocated memory). Check the
2311 // caller if you hit this assert.
2312 assert(addr == bottom, "sanity check");
2313
2314 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2315 return ::mprotect(bottom, size, prot) == 0;
2316 }
2317
2318 // Set protections specified
2319 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2320 bool is_committed) {
2321 unsigned int p = 0;
2322 switch (prot) {
2323 case MEM_PROT_NONE: p = PROT_NONE; break;
2324 case MEM_PROT_READ: p = PROT_READ; break;
2325 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2326 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2327 default:
2328 ShouldNotReachHere();
2329 }
2330 // is_committed is unused.
2331 return bsd_mprotect(addr, bytes, p);
2332 }
2333
2334 bool os::guard_memory(char* addr, size_t size) {
2335 return bsd_mprotect(addr, size, PROT_NONE);
2336 }
2337
2338 bool os::unguard_memory(char* addr, size_t size) {
2339 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2340 }
2341
2342 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2343 return false;
2344 }
2345
2346 // Large page support
2347
2348 static size_t _large_page_size = 0;
2349
2350 void os::large_page_init() {
2351 }
2352
2353
2354 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2355 fatal("This code is not used or maintained.");
2356
2357 // "exec" is passed in but not used. Creating the shared image for
2358 // the code cache doesn't have an SHM_X executable permission to check.
2359 assert(UseLargePages && UseSHM, "only for SHM large pages");
2360
2361 key_t key = IPC_PRIVATE;
2362 char *addr;
2363
2364 bool warn_on_failure = UseLargePages &&
2365 (!FLAG_IS_DEFAULT(UseLargePages) ||
2366 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2367
2368 // Create a large shared memory region to attach to based on size.
2369 // Currently, size is the total size of the heap
2370 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2371 if (shmid == -1) {
2372 // Possible reasons for shmget failure:
2373 // 1. shmmax is too small for Java heap.
2374 // > check shmmax value: cat /proc/sys/kernel/shmmax
2375 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2376 // 2. not enough large page memory.
2377 // > check available large pages: cat /proc/meminfo
2378 // > increase amount of large pages:
2379 // echo new_value > /proc/sys/vm/nr_hugepages
2380 // Note 1: different Bsd may use different name for this property,
2381 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2382 // Note 2: it's possible there's enough physical memory available but
2383 // they are so fragmented after a long run that they can't
2384 // coalesce into large pages. Try to reserve large pages when
2385 // the system is still "fresh".
2386 if (warn_on_failure) {
2387 warning("Failed to reserve shared memory (errno = %d).", errno);
2388 }
2389 return NULL;
2390 }
2391
2392 // attach to the region
2393 addr = (char*)shmat(shmid, req_addr, 0);
2394 int err = errno;
2395
2396 // Remove shmid. If shmat() is successful, the actual shared memory segment
2397 // will be deleted when it's detached by shmdt() or when the process
2398 // terminates. If shmat() is not successful this will remove the shared
2399 // segment immediately.
2400 shmctl(shmid, IPC_RMID, NULL);
2401
2402 if ((intptr_t)addr == -1) {
2403 if (warn_on_failure) {
2404 warning("Failed to attach shared memory (errno = %d).", err);
2405 }
2406 return NULL;
2407 }
2408
2409 // The memory is committed
2410 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2411
2412 return addr;
2413 }
2414
2415 bool os::release_memory_special(char* base, size_t bytes) {
2416 if (MemTracker::tracking_level() > NMT_minimal) {
2417 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2418 // detaching the SHM segment will also delete it, see reserve_memory_special()
2419 int rslt = shmdt(base);
2420 if (rslt == 0) {
2421 tkr.record((address)base, bytes);
2422 return true;
2423 } else {
2424 return false;
2425 }
2426 } else {
2427 return shmdt(base) == 0;
2428 }
2429 }
2430
2431 size_t os::large_page_size() {
2432 return _large_page_size;
2433 }
2434
2435 // HugeTLBFS allows application to commit large page memory on demand;
2436 // with SysV SHM the entire memory region must be allocated as shared
2437 // memory.
2438 bool os::can_commit_large_page_memory() {
2439 return UseHugeTLBFS;
2440 }
2441
2442 bool os::can_execute_large_page_memory() {
2443 return UseHugeTLBFS;
2444 }
2445
2446 // Reserve memory at an arbitrary address, only if that area is
2447 // available (and not reserved for something else).
2448
2449 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2450 const int max_tries = 10;
2451 char* base[max_tries];
2452 size_t size[max_tries];
2453 const size_t gap = 0x000000;
2454
2455 // Assert only that the size is a multiple of the page size, since
2456 // that's all that mmap requires, and since that's all we really know
2457 // about at this low abstraction level. If we need higher alignment,
2458 // we can either pass an alignment to this method or verify alignment
2459 // in one of the methods further up the call chain. See bug 5044738.
2460 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2461
2462 // Repeatedly allocate blocks until the block is allocated at the
2463 // right spot.
2464
2465 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2466 // if kernel honors the hint then we can return immediately.
2467 char * addr = anon_mmap(requested_addr, bytes, false);
2468 if (addr == requested_addr) {
2469 return requested_addr;
2470 }
2471
2472 if (addr != NULL) {
2473 // mmap() is successful but it fails to reserve at the requested address
2474 anon_munmap(addr, bytes);
2475 }
2476
2477 int i;
2478 for (i = 0; i < max_tries; ++i) {
2479 base[i] = reserve_memory(bytes);
2480
2481 if (base[i] != NULL) {
2482 // Is this the block we wanted?
2483 if (base[i] == requested_addr) {
2484 size[i] = bytes;
2485 break;
2486 }
2487
2488 // Does this overlap the block we wanted? Give back the overlapped
2489 // parts and try again.
2490
2491 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2492 if (top_overlap >= 0 && top_overlap < bytes) {
2493 unmap_memory(base[i], top_overlap);
2494 base[i] += top_overlap;
2495 size[i] = bytes - top_overlap;
2496 } else {
2497 size_t bottom_overlap = base[i] + bytes - requested_addr;
2498 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2499 unmap_memory(requested_addr, bottom_overlap);
2500 size[i] = bytes - bottom_overlap;
2501 } else {
2502 size[i] = bytes;
2503 }
2504 }
2505 }
2506 }
2507
2508 // Give back the unused reserved pieces.
2509
2510 for (int j = 0; j < i; ++j) {
2511 if (base[j] != NULL) {
2512 unmap_memory(base[j], size[j]);
2513 }
2514 }
2515
2516 if (i < max_tries) {
2517 return requested_addr;
2518 } else {
2519 return NULL;
2520 }
2521 }
2522
2523 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2524 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2525 }
2526
2527 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2528 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2529 }
2530
2531 void os::naked_short_sleep(jlong ms) {
2532 struct timespec req;
2533
2534 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2535 req.tv_sec = 0;
2536 if (ms > 0) {
2537 req.tv_nsec = (ms % 1000) * 1000000;
2538 } else {
2539 req.tv_nsec = 1;
2540 }
2541
2542 nanosleep(&req, NULL);
2543
2544 return;
2545 }
2546
2547 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2548 void os::infinite_sleep() {
2549 while (true) { // sleep forever ...
2550 ::sleep(100); // ... 100 seconds at a time
2551 }
2552 }
2553
2554 // Used to convert frequent JVM_Yield() to nops
2555 bool os::dont_yield() {
2556 return DontYieldALot;
2557 }
2558
2559 void os::naked_yield() {
2560 sched_yield();
2561 }
2562
2563 ////////////////////////////////////////////////////////////////////////////////
2564 // thread priority support
2565
2566 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2567 // only supports dynamic priority, static priority must be zero. For real-time
2568 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2569 // However, for large multi-threaded applications, SCHED_RR is not only slower
2570 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2571 // of 5 runs - Sep 2005).
2572 //
2573 // The following code actually changes the niceness of kernel-thread/LWP. It
2574 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2575 // not the entire user process, and user level threads are 1:1 mapped to kernel
2576 // threads. It has always been the case, but could change in the future. For
2577 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2578 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2579
2580 #if !defined(__APPLE__)
2581 int os::java_to_os_priority[CriticalPriority + 1] = {
2582 19, // 0 Entry should never be used
2583
2584 0, // 1 MinPriority
2585 3, // 2
2586 6, // 3
2587
2588 10, // 4
2589 15, // 5 NormPriority
2590 18, // 6
2591
2592 21, // 7
2593 25, // 8
2594 28, // 9 NearMaxPriority
2595
2596 31, // 10 MaxPriority
2597
2598 31 // 11 CriticalPriority
2599 };
2600 #else
2601 // Using Mach high-level priority assignments
2602 int os::java_to_os_priority[CriticalPriority + 1] = {
2603 0, // 0 Entry should never be used (MINPRI_USER)
2604
2605 27, // 1 MinPriority
2606 28, // 2
2607 29, // 3
2608
2609 30, // 4
2610 31, // 5 NormPriority (BASEPRI_DEFAULT)
2611 32, // 6
2612
2613 33, // 7
2614 34, // 8
2615 35, // 9 NearMaxPriority
2616
2617 36, // 10 MaxPriority
2618
2619 36 // 11 CriticalPriority
2620 };
2621 #endif
2622
2623 static int prio_init() {
2624 if (ThreadPriorityPolicy == 1) {
2625 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2626 // if effective uid is not root. Perhaps, a more elegant way of doing
2627 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2628 if (geteuid() != 0) {
2629 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2630 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2631 }
2632 ThreadPriorityPolicy = 0;
2633 }
2634 }
2635 if (UseCriticalJavaThreadPriority) {
2636 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2637 }
2638 return 0;
2639 }
2640
2641 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2642 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2643
2644 #ifdef __OpenBSD__
2645 // OpenBSD pthread_setprio starves low priority threads
2646 return OS_OK;
2647 #elif defined(__FreeBSD__)
2648 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2649 #elif defined(__APPLE__) || defined(__NetBSD__)
2650 struct sched_param sp;
2651 int policy;
2652 pthread_t self = pthread_self();
2653
2654 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2655 return OS_ERR;
2656 }
2657
2658 sp.sched_priority = newpri;
2659 if (pthread_setschedparam(self, policy, &sp) != 0) {
2660 return OS_ERR;
2661 }
2662
2663 return OS_OK;
2664 #else
2665 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2666 return (ret == 0) ? OS_OK : OS_ERR;
2667 #endif
2668 }
2669
2670 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2671 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2672 *priority_ptr = java_to_os_priority[NormPriority];
2673 return OS_OK;
2674 }
2675
2676 errno = 0;
2677 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2678 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2679 #elif defined(__APPLE__) || defined(__NetBSD__)
2680 int policy;
2681 struct sched_param sp;
2682
2683 pthread_getschedparam(pthread_self(), &policy, &sp);
2684 *priority_ptr = sp.sched_priority;
2685 #else
2686 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2687 #endif
2688 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2689 }
2690
2691 // Hint to the underlying OS that a task switch would not be good.
2692 // Void return because it's a hint and can fail.
2693 void os::hint_no_preempt() {}
2694
2695 ////////////////////////////////////////////////////////////////////////////////
2696 // suspend/resume support
2697
2698 // the low-level signal-based suspend/resume support is a remnant from the
2699 // old VM-suspension that used to be for java-suspension, safepoints etc,
2700 // within hotspot. Now there is a single use-case for this:
2701 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2702 // that runs in the watcher thread.
2703 // The remaining code is greatly simplified from the more general suspension
2704 // code that used to be used.
2705 //
2706 // The protocol is quite simple:
2707 // - suspend:
2708 // - sends a signal to the target thread
2709 // - polls the suspend state of the osthread using a yield loop
2710 // - target thread signal handler (SR_handler) sets suspend state
2711 // and blocks in sigsuspend until continued
2712 // - resume:
2713 // - sets target osthread state to continue
2714 // - sends signal to end the sigsuspend loop in the SR_handler
2715 //
2716 // Note that the SR_lock plays no role in this suspend/resume protocol.
2717
2718 static void resume_clear_context(OSThread *osthread) {
2719 osthread->set_ucontext(NULL);
2720 osthread->set_siginfo(NULL);
2721 }
2722
2723 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2724 osthread->set_ucontext(context);
2725 osthread->set_siginfo(siginfo);
2726 }
2727
2728 // Handler function invoked when a thread's execution is suspended or
2729 // resumed. We have to be careful that only async-safe functions are
2730 // called here (Note: most pthread functions are not async safe and
2731 // should be avoided.)
2732 //
2733 // Note: sigwait() is a more natural fit than sigsuspend() from an
2734 // interface point of view, but sigwait() prevents the signal hander
2735 // from being run. libpthread would get very confused by not having
2736 // its signal handlers run and prevents sigwait()'s use with the
2737 // mutex granting granting signal.
2738 //
2739 // Currently only ever called on the VMThread or JavaThread
2740 //
2741 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2742 // Save and restore errno to avoid confusing native code with EINTR
2743 // after sigsuspend.
2744 int old_errno = errno;
2745
2746 Thread* thread = Thread::current();
2747 OSThread* osthread = thread->osthread();
2748 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2749
2750 os::SuspendResume::State current = osthread->sr.state();
2751 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2752 suspend_save_context(osthread, siginfo, context);
2753
2754 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2755 os::SuspendResume::State state = osthread->sr.suspended();
2756 if (state == os::SuspendResume::SR_SUSPENDED) {
2757 sigset_t suspend_set; // signals for sigsuspend()
2758
2759 // get current set of blocked signals and unblock resume signal
2760 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2761 sigdelset(&suspend_set, SR_signum);
2762
2763 sr_semaphore.signal();
2764 // wait here until we are resumed
2765 while (1) {
2766 sigsuspend(&suspend_set);
2767
2768 os::SuspendResume::State result = osthread->sr.running();
2769 if (result == os::SuspendResume::SR_RUNNING) {
2770 sr_semaphore.signal();
2771 break;
2772 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2773 ShouldNotReachHere();
2774 }
2775 }
2776
2777 } else if (state == os::SuspendResume::SR_RUNNING) {
2778 // request was cancelled, continue
2779 } else {
2780 ShouldNotReachHere();
2781 }
2782
2783 resume_clear_context(osthread);
2784 } else if (current == os::SuspendResume::SR_RUNNING) {
2785 // request was cancelled, continue
2786 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2787 // ignore
2788 } else {
2789 // ignore
2790 }
2791
2792 errno = old_errno;
2793 }
2794
2795
2796 static int SR_initialize() {
2797 struct sigaction act;
2798 char *s;
2799 // Get signal number to use for suspend/resume
2800 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2801 int sig = ::strtol(s, 0, 10);
2802 if (sig > 0 || sig < NSIG) {
2803 SR_signum = sig;
2804 }
2805 }
2806
2807 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2808 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2809
2810 sigemptyset(&SR_sigset);
2811 sigaddset(&SR_sigset, SR_signum);
2812
2813 // Set up signal handler for suspend/resume
2814 act.sa_flags = SA_RESTART|SA_SIGINFO;
2815 act.sa_handler = (void (*)(int)) SR_handler;
2816
2817 // SR_signum is blocked by default.
2818 // 4528190 - We also need to block pthread restart signal (32 on all
2819 // supported Bsd platforms). Note that BsdThreads need to block
2820 // this signal for all threads to work properly. So we don't have
2821 // to use hard-coded signal number when setting up the mask.
2822 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2823
2824 if (sigaction(SR_signum, &act, 0) == -1) {
2825 return -1;
2826 }
2827
2828 // Save signal flag
2829 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2830 return 0;
2831 }
2832
2833 static int sr_notify(OSThread* osthread) {
2834 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2835 assert_status(status == 0, status, "pthread_kill");
2836 return status;
2837 }
2838
2839 // "Randomly" selected value for how long we want to spin
2840 // before bailing out on suspending a thread, also how often
2841 // we send a signal to a thread we want to resume
2842 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2843 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2844
2845 // returns true on success and false on error - really an error is fatal
2846 // but this seems the normal response to library errors
2847 static bool do_suspend(OSThread* osthread) {
2848 assert(osthread->sr.is_running(), "thread should be running");
2849 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2850
2851 // mark as suspended and send signal
2852 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2853 // failed to switch, state wasn't running?
2854 ShouldNotReachHere();
2855 return false;
2856 }
2857
2858 if (sr_notify(osthread) != 0) {
2859 ShouldNotReachHere();
2860 }
2861
2862 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2863 while (true) {
2864 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2865 break;
2866 } else {
2867 // timeout
2868 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2869 if (cancelled == os::SuspendResume::SR_RUNNING) {
2870 return false;
2871 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2872 // make sure that we consume the signal on the semaphore as well
2873 sr_semaphore.wait();
2874 break;
2875 } else {
2876 ShouldNotReachHere();
2877 return false;
2878 }
2879 }
2880 }
2881
2882 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2883 return true;
2884 }
2885
2886 static void do_resume(OSThread* osthread) {
2887 assert(osthread->sr.is_suspended(), "thread should be suspended");
2888 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2889
2890 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2891 // failed to switch to WAKEUP_REQUEST
2892 ShouldNotReachHere();
2893 return;
2894 }
2895
2896 while (true) {
2897 if (sr_notify(osthread) == 0) {
2898 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2899 if (osthread->sr.is_running()) {
2900 return;
2901 }
2902 }
2903 } else {
2904 ShouldNotReachHere();
2905 }
2906 }
2907
2908 guarantee(osthread->sr.is_running(), "Must be running!");
2909 }
2910
2911 ///////////////////////////////////////////////////////////////////////////////////
2912 // signal handling (except suspend/resume)
2913
2914 // This routine may be used by user applications as a "hook" to catch signals.
2915 // The user-defined signal handler must pass unrecognized signals to this
2916 // routine, and if it returns true (non-zero), then the signal handler must
2917 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2918 // routine will never retun false (zero), but instead will execute a VM panic
2919 // routine kill the process.
2920 //
2921 // If this routine returns false, it is OK to call it again. This allows
2922 // the user-defined signal handler to perform checks either before or after
2923 // the VM performs its own checks. Naturally, the user code would be making
2924 // a serious error if it tried to handle an exception (such as a null check
2925 // or breakpoint) that the VM was generating for its own correct operation.
2926 //
2927 // This routine may recognize any of the following kinds of signals:
2928 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2929 // It should be consulted by handlers for any of those signals.
2930 //
2931 // The caller of this routine must pass in the three arguments supplied
2932 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2933 // field of the structure passed to sigaction(). This routine assumes that
2934 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2935 //
2936 // Note that the VM will print warnings if it detects conflicting signal
2937 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2938 //
2939 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2940 void* ucontext,
2941 int abort_if_unrecognized);
2942
2943 void signalHandler(int sig, siginfo_t* info, void* uc) {
2944 assert(info != NULL && uc != NULL, "it must be old kernel");
2945 int orig_errno = errno; // Preserve errno value over signal handler.
2946 JVM_handle_bsd_signal(sig, info, uc, true);
2947 errno = orig_errno;
2948 }
2949
2950
2951 // This boolean allows users to forward their own non-matching signals
2952 // to JVM_handle_bsd_signal, harmlessly.
2953 bool os::Bsd::signal_handlers_are_installed = false;
2954
2955 // For signal-chaining
2956 struct sigaction os::Bsd::sigact[MAXSIGNUM];
2957 unsigned int os::Bsd::sigs = 0;
2958 bool os::Bsd::libjsig_is_loaded = false;
2959 typedef struct sigaction *(*get_signal_t)(int);
2960 get_signal_t os::Bsd::get_signal_action = NULL;
2961
2962 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2963 struct sigaction *actp = NULL;
2964
2965 if (libjsig_is_loaded) {
2966 // Retrieve the old signal handler from libjsig
2967 actp = (*get_signal_action)(sig);
2968 }
2969 if (actp == NULL) {
2970 // Retrieve the preinstalled signal handler from jvm
2971 actp = get_preinstalled_handler(sig);
2972 }
2973
2974 return actp;
2975 }
2976
2977 static bool call_chained_handler(struct sigaction *actp, int sig,
2978 siginfo_t *siginfo, void *context) {
2979 // Call the old signal handler
2980 if (actp->sa_handler == SIG_DFL) {
2981 // It's more reasonable to let jvm treat it as an unexpected exception
2982 // instead of taking the default action.
2983 return false;
2984 } else if (actp->sa_handler != SIG_IGN) {
2985 if ((actp->sa_flags & SA_NODEFER) == 0) {
2986 // automaticlly block the signal
2987 sigaddset(&(actp->sa_mask), sig);
2988 }
2989
2990 sa_handler_t hand;
2991 sa_sigaction_t sa;
2992 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2993 // retrieve the chained handler
2994 if (siginfo_flag_set) {
2995 sa = actp->sa_sigaction;
2996 } else {
2997 hand = actp->sa_handler;
2998 }
2999
3000 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3001 actp->sa_handler = SIG_DFL;
3002 }
3003
3004 // try to honor the signal mask
3005 sigset_t oset;
3006 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3007
3008 // call into the chained handler
3009 if (siginfo_flag_set) {
3010 (*sa)(sig, siginfo, context);
3011 } else {
3012 (*hand)(sig);
3013 }
3014
3015 // restore the signal mask
3016 pthread_sigmask(SIG_SETMASK, &oset, 0);
3017 }
3018 // Tell jvm's signal handler the signal is taken care of.
3019 return true;
3020 }
3021
3022 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3023 bool chained = false;
3024 // signal-chaining
3025 if (UseSignalChaining) {
3026 struct sigaction *actp = get_chained_signal_action(sig);
3027 if (actp != NULL) {
3028 chained = call_chained_handler(actp, sig, siginfo, context);
3029 }
3030 }
3031 return chained;
3032 }
3033
3034 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3035 if ((((unsigned int)1 << sig) & sigs) != 0) {
3036 return &sigact[sig];
3037 }
3038 return NULL;
3039 }
3040
3041 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3042 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3043 sigact[sig] = oldAct;
3044 sigs |= (unsigned int)1 << sig;
3045 }
3046
3047 // for diagnostic
3048 int os::Bsd::sigflags[MAXSIGNUM];
3049
3050 int os::Bsd::get_our_sigflags(int sig) {
3051 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3052 return sigflags[sig];
3053 }
3054
3055 void os::Bsd::set_our_sigflags(int sig, int flags) {
3056 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3057 sigflags[sig] = flags;
3058 }
3059
3060 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3061 // Check for overwrite.
3062 struct sigaction oldAct;
3063 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3064
3065 void* oldhand = oldAct.sa_sigaction
3066 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3067 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3068 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3069 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3070 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3071 if (AllowUserSignalHandlers || !set_installed) {
3072 // Do not overwrite; user takes responsibility to forward to us.
3073 return;
3074 } else if (UseSignalChaining) {
3075 // save the old handler in jvm
3076 save_preinstalled_handler(sig, oldAct);
3077 // libjsig also interposes the sigaction() call below and saves the
3078 // old sigaction on it own.
3079 } else {
3080 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3081 "%#lx for signal %d.", (long)oldhand, sig));
3082 }
3083 }
3084
3085 struct sigaction sigAct;
3086 sigfillset(&(sigAct.sa_mask));
3087 sigAct.sa_handler = SIG_DFL;
3088 if (!set_installed) {
3089 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3090 } else {
3091 sigAct.sa_sigaction = signalHandler;
3092 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3093 }
3094 #ifdef __APPLE__
3095 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3096 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3097 // if the signal handler declares it will handle it on alternate stack.
3098 // Notice we only declare we will handle it on alt stack, but we are not
3099 // actually going to use real alt stack - this is just a workaround.
3100 // Please see ux_exception.c, method catch_mach_exception_raise for details
3101 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3102 if (sig == SIGSEGV) {
3103 sigAct.sa_flags |= SA_ONSTACK;
3104 }
3105 #endif
3106
3107 // Save flags, which are set by ours
3108 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3109 sigflags[sig] = sigAct.sa_flags;
3110
3111 int ret = sigaction(sig, &sigAct, &oldAct);
3112 assert(ret == 0, "check");
3113
3114 void* oldhand2 = oldAct.sa_sigaction
3115 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3116 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3117 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3118 }
3119
3120 // install signal handlers for signals that HotSpot needs to
3121 // handle in order to support Java-level exception handling.
3122
3123 void os::Bsd::install_signal_handlers() {
3124 if (!signal_handlers_are_installed) {
3125 signal_handlers_are_installed = true;
3126
3127 // signal-chaining
3128 typedef void (*signal_setting_t)();
3129 signal_setting_t begin_signal_setting = NULL;
3130 signal_setting_t end_signal_setting = NULL;
3131 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3132 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3133 if (begin_signal_setting != NULL) {
3134 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3135 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3136 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3137 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3138 libjsig_is_loaded = true;
3139 assert(UseSignalChaining, "should enable signal-chaining");
3140 }
3141 if (libjsig_is_loaded) {
3142 // Tell libjsig jvm is setting signal handlers
3143 (*begin_signal_setting)();
3144 }
3145
3146 set_signal_handler(SIGSEGV, true);
3147 set_signal_handler(SIGPIPE, true);
3148 set_signal_handler(SIGBUS, true);
3149 set_signal_handler(SIGILL, true);
3150 set_signal_handler(SIGFPE, true);
3151 set_signal_handler(SIGXFSZ, true);
3152
3153 #if defined(__APPLE__)
3154 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3155 // signals caught and handled by the JVM. To work around this, we reset the mach task
3156 // signal handler that's placed on our process by CrashReporter. This disables
3157 // CrashReporter-based reporting.
3158 //
3159 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3160 // on caught fatal signals.
3161 //
3162 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3163 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3164 // exception handling, while leaving the standard BSD signal handlers functional.
3165 kern_return_t kr;
3166 kr = task_set_exception_ports(mach_task_self(),
3167 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3168 MACH_PORT_NULL,
3169 EXCEPTION_STATE_IDENTITY,
3170 MACHINE_THREAD_STATE);
3171
3172 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3173 #endif
3174
3175 if (libjsig_is_loaded) {
3176 // Tell libjsig jvm finishes setting signal handlers
3177 (*end_signal_setting)();
3178 }
3179
3180 // We don't activate signal checker if libjsig is in place, we trust ourselves
3181 // and if UserSignalHandler is installed all bets are off
3182 if (CheckJNICalls) {
3183 if (libjsig_is_loaded) {
3184 if (PrintJNIResolving) {
3185 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3186 }
3187 check_signals = false;
3188 }
3189 if (AllowUserSignalHandlers) {
3190 if (PrintJNIResolving) {
3191 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3192 }
3193 check_signals = false;
3194 }
3195 }
3196 }
3197 }
3198
3199
3200 /////
3201 // glibc on Bsd platform uses non-documented flag
3202 // to indicate, that some special sort of signal
3203 // trampoline is used.
3204 // We will never set this flag, and we should
3205 // ignore this flag in our diagnostic
3206 #ifdef SIGNIFICANT_SIGNAL_MASK
3207 #undef SIGNIFICANT_SIGNAL_MASK
3208 #endif
3209 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3210
3211 static const char* get_signal_handler_name(address handler,
3212 char* buf, int buflen) {
3213 int offset;
3214 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3215 if (found) {
3216 // skip directory names
3217 const char *p1, *p2;
3218 p1 = buf;
3219 size_t len = strlen(os::file_separator());
3220 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3221 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3222 } else {
3223 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3224 }
3225 return buf;
3226 }
3227
3228 static void print_signal_handler(outputStream* st, int sig,
3229 char* buf, size_t buflen) {
3230 struct sigaction sa;
3231
3232 sigaction(sig, NULL, &sa);
3233
3234 // See comment for SIGNIFICANT_SIGNAL_MASK define
3235 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3236
3237 st->print("%s: ", os::exception_name(sig, buf, buflen));
3238
3239 address handler = (sa.sa_flags & SA_SIGINFO)
3240 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3241 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3242
3243 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3244 st->print("SIG_DFL");
3245 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3246 st->print("SIG_IGN");
3247 } else {
3248 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3249 }
3250
3251 st->print(", sa_mask[0]=");
3252 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3253
3254 address rh = VMError::get_resetted_sighandler(sig);
3255 // May be, handler was resetted by VMError?
3256 if (rh != NULL) {
3257 handler = rh;
3258 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3259 }
3260
3261 st->print(", sa_flags=");
3262 os::Posix::print_sa_flags(st, sa.sa_flags);
3263
3264 // Check: is it our handler?
3265 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3266 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3267 // It is our signal handler
3268 // check for flags, reset system-used one!
3269 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3270 st->print(
3271 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3272 os::Bsd::get_our_sigflags(sig));
3273 }
3274 }
3275 st->cr();
3276 }
3277
3278
3279 #define DO_SIGNAL_CHECK(sig) \
3280 do { \
3281 if (!sigismember(&check_signal_done, sig)) { \
3282 os::Bsd::check_signal_handler(sig); \
3283 } \
3284 } while (0)
3285
3286 // This method is a periodic task to check for misbehaving JNI applications
3287 // under CheckJNI, we can add any periodic checks here
3288
3289 void os::run_periodic_checks() {
3290
3291 if (check_signals == false) return;
3292
3293 // SEGV and BUS if overridden could potentially prevent
3294 // generation of hs*.log in the event of a crash, debugging
3295 // such a case can be very challenging, so we absolutely
3296 // check the following for a good measure:
3297 DO_SIGNAL_CHECK(SIGSEGV);
3298 DO_SIGNAL_CHECK(SIGILL);
3299 DO_SIGNAL_CHECK(SIGFPE);
3300 DO_SIGNAL_CHECK(SIGBUS);
3301 DO_SIGNAL_CHECK(SIGPIPE);
3302 DO_SIGNAL_CHECK(SIGXFSZ);
3303
3304
3305 // ReduceSignalUsage allows the user to override these handlers
3306 // see comments at the very top and jvm_solaris.h
3307 if (!ReduceSignalUsage) {
3308 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3309 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3310 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3311 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3312 }
3313
3314 DO_SIGNAL_CHECK(SR_signum);
3315 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3316 }
3317
3318 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3319
3320 static os_sigaction_t os_sigaction = NULL;
3321
3322 void os::Bsd::check_signal_handler(int sig) {
3323 char buf[O_BUFLEN];
3324 address jvmHandler = NULL;
3325
3326
3327 struct sigaction act;
3328 if (os_sigaction == NULL) {
3329 // only trust the default sigaction, in case it has been interposed
3330 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3331 if (os_sigaction == NULL) return;
3332 }
3333
3334 os_sigaction(sig, (struct sigaction*)NULL, &act);
3335
3336
3337 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3338
3339 address thisHandler = (act.sa_flags & SA_SIGINFO)
3340 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3341 : CAST_FROM_FN_PTR(address, act.sa_handler);
3342
3343
3344 switch (sig) {
3345 case SIGSEGV:
3346 case SIGBUS:
3347 case SIGFPE:
3348 case SIGPIPE:
3349 case SIGILL:
3350 case SIGXFSZ:
3351 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3352 break;
3353
3354 case SHUTDOWN1_SIGNAL:
3355 case SHUTDOWN2_SIGNAL:
3356 case SHUTDOWN3_SIGNAL:
3357 case BREAK_SIGNAL:
3358 jvmHandler = (address)user_handler();
3359 break;
3360
3361 case INTERRUPT_SIGNAL:
3362 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3363 break;
3364
3365 default:
3366 if (sig == SR_signum) {
3367 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3368 } else {
3369 return;
3370 }
3371 break;
3372 }
3373
3374 if (thisHandler != jvmHandler) {
3375 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3376 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3377 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3378 // No need to check this sig any longer
3379 sigaddset(&check_signal_done, sig);
3380 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3381 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3382 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3383 exception_name(sig, buf, O_BUFLEN));
3384 }
3385 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3386 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3387 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3388 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3389 // No need to check this sig any longer
3390 sigaddset(&check_signal_done, sig);
3391 }
3392
3393 // Dump all the signal
3394 if (sigismember(&check_signal_done, sig)) {
3395 print_signal_handlers(tty, buf, O_BUFLEN);
3396 }
3397 }
3398
3399 extern void report_error(char* file_name, int line_no, char* title,
3400 char* format, ...);
3401
3402 extern bool signal_name(int signo, char* buf, size_t len);
3403
3404 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3405 if (0 < exception_code && exception_code <= SIGRTMAX) {
3406 // signal
3407 if (!signal_name(exception_code, buf, size)) {
3408 jio_snprintf(buf, size, "SIG%d", exception_code);
3409 }
3410 return buf;
3411 } else {
3412 return NULL;
3413 }
3414 }
3415
3416 // this is called _before_ the most of global arguments have been parsed
3417 void os::init(void) {
3418 char dummy; // used to get a guess on initial stack address
3419 // first_hrtime = gethrtime();
3420
3421 // With BsdThreads the JavaMain thread pid (primordial thread)
3422 // is different than the pid of the java launcher thread.
3423 // So, on Bsd, the launcher thread pid is passed to the VM
3424 // via the sun.java.launcher.pid property.
3425 // Use this property instead of getpid() if it was correctly passed.
3426 // See bug 6351349.
3427 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3428
3429 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3430
3431 clock_tics_per_sec = CLK_TCK;
3432
3433 init_random(1234567);
3434
3435 ThreadCritical::initialize();
3436
3437 Bsd::set_page_size(getpagesize());
3438 if (Bsd::page_size() == -1) {
3439 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3440 strerror(errno)));
3441 }
3442 init_page_sizes((size_t) Bsd::page_size());
3443
3444 Bsd::initialize_system_info();
3445
3446 // main_thread points to the aboriginal thread
3447 Bsd::_main_thread = pthread_self();
3448
3449 Bsd::clock_init();
3450 initial_time_count = javaTimeNanos();
3451
3452 #ifdef __APPLE__
3453 // XXXDARWIN
3454 // Work around the unaligned VM callbacks in hotspot's
3455 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3456 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3457 // alignment when doing symbol lookup. To work around this, we force early
3458 // binding of all symbols now, thus binding when alignment is known-good.
3459 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3460 #endif
3461 }
3462
3463 // To install functions for atexit system call
3464 extern "C" {
3465 static void perfMemory_exit_helper() {
3466 perfMemory_exit();
3467 }
3468 }
3469
3470 // this is called _after_ the global arguments have been parsed
3471 jint os::init_2(void) {
3472 // Allocate a single page and mark it as readable for safepoint polling
3473 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3474 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3475
3476 os::set_polling_page(polling_page);
3477
3478 #ifndef PRODUCT
3479 if (Verbose && PrintMiscellaneous) {
3480 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n",
3481 (intptr_t)polling_page);
3482 }
3483 #endif
3484
3485 if (!UseMembar) {
3486 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3487 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3488 os::set_memory_serialize_page(mem_serialize_page);
3489
3490 #ifndef PRODUCT
3491 if (Verbose && PrintMiscellaneous) {
3492 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n",
3493 (intptr_t)mem_serialize_page);
3494 }
3495 #endif
3496 }
3497
3498 // initialize suspend/resume support - must do this before signal_sets_init()
3499 if (SR_initialize() != 0) {
3500 perror("SR_initialize failed");
3501 return JNI_ERR;
3502 }
3503
3504 Bsd::signal_sets_init();
3505 Bsd::install_signal_handlers();
3506
3507 // Check minimum allowable stack size for thread creation and to initialize
3508 // the java system classes, including StackOverflowError - depends on page
3509 // size. Add a page for compiler2 recursion in main thread.
3510 // Add in 2*BytesPerWord times page size to account for VM stack during
3511 // class initialization depending on 32 or 64 bit VM.
3512 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3513 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3514 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3515
3516 size_t threadStackSizeInBytes = ThreadStackSize * K;
3517 if (threadStackSizeInBytes != 0 &&
3518 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3519 tty->print_cr("\nThe stack size specified is too small, "
3520 "Specify at least %dk",
3521 os::Bsd::min_stack_allowed/ K);
3522 return JNI_ERR;
3523 }
3524
3525 // Make the stack size a multiple of the page size so that
3526 // the yellow/red zones can be guarded.
3527 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3528 vm_page_size()));
3529
3530 if (MaxFDLimit) {
3531 // set the number of file descriptors to max. print out error
3532 // if getrlimit/setrlimit fails but continue regardless.
3533 struct rlimit nbr_files;
3534 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3535 if (status != 0) {
3536 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3537 perror("os::init_2 getrlimit failed");
3538 }
3539 } else {
3540 nbr_files.rlim_cur = nbr_files.rlim_max;
3541
3542 #ifdef __APPLE__
3543 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3544 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3545 // be used instead
3546 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3547 #endif
3548
3549 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3550 if (status != 0) {
3551 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3552 perror("os::init_2 setrlimit failed");
3553 }
3554 }
3555 }
3556 }
3557
3558 // at-exit methods are called in the reverse order of their registration.
3559 // atexit functions are called on return from main or as a result of a
3560 // call to exit(3C). There can be only 32 of these functions registered
3561 // and atexit() does not set errno.
3562
3563 if (PerfAllowAtExitRegistration) {
3564 // only register atexit functions if PerfAllowAtExitRegistration is set.
3565 // atexit functions can be delayed until process exit time, which
3566 // can be problematic for embedded VM situations. Embedded VMs should
3567 // call DestroyJavaVM() to assure that VM resources are released.
3568
3569 // note: perfMemory_exit_helper atexit function may be removed in
3570 // the future if the appropriate cleanup code can be added to the
3571 // VM_Exit VMOperation's doit method.
3572 if (atexit(perfMemory_exit_helper) != 0) {
3573 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3574 }
3575 }
3576
3577 // initialize thread priority policy
3578 prio_init();
3579
3580 #ifdef __APPLE__
3581 // dynamically link to objective c gc registration
3582 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3583 if (handleLibObjc != NULL) {
3584 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3585 }
3586 #endif
3587
3588 return JNI_OK;
3589 }
3590
3591 // Mark the polling page as unreadable
3592 void os::make_polling_page_unreadable(void) {
3593 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3594 fatal("Could not disable polling page");
3595 }
3596 }
3597
3598 // Mark the polling page as readable
3599 void os::make_polling_page_readable(void) {
3600 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3601 fatal("Could not enable polling page");
3602 }
3603 }
3604
3605 int os::active_processor_count() {
3606 return _processor_count;
3607 }
3608
3609 void os::set_native_thread_name(const char *name) {
3610 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3611 // This is only supported in Snow Leopard and beyond
3612 if (name != NULL) {
3613 // Add a "Java: " prefix to the name
3614 char buf[MAXTHREADNAMESIZE];
3615 snprintf(buf, sizeof(buf), "Java: %s", name);
3616 pthread_setname_np(buf);
3617 }
3618 #endif
3619 }
3620
3621 bool os::distribute_processes(uint length, uint* distribution) {
3622 // Not yet implemented.
3623 return false;
3624 }
3625
3626 bool os::bind_to_processor(uint processor_id) {
3627 // Not yet implemented.
3628 return false;
3629 }
3630
3631 void os::SuspendedThreadTask::internal_do_task() {
3632 if (do_suspend(_thread->osthread())) {
3633 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3634 do_task(context);
3635 do_resume(_thread->osthread());
3636 }
3637 }
3638
3639 ///
3640 class PcFetcher : public os::SuspendedThreadTask {
3641 public:
3642 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3643 ExtendedPC result();
3644 protected:
3645 void do_task(const os::SuspendedThreadTaskContext& context);
3646 private:
3647 ExtendedPC _epc;
3648 };
3649
3650 ExtendedPC PcFetcher::result() {
3651 guarantee(is_done(), "task is not done yet.");
3652 return _epc;
3653 }
3654
3655 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3656 Thread* thread = context.thread();
3657 OSThread* osthread = thread->osthread();
3658 if (osthread->ucontext() != NULL) {
3659 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3660 } else {
3661 // NULL context is unexpected, double-check this is the VMThread
3662 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3663 }
3664 }
3665
3666 // Suspends the target using the signal mechanism and then grabs the PC before
3667 // resuming the target. Used by the flat-profiler only
3668 ExtendedPC os::get_thread_pc(Thread* thread) {
3669 // Make sure that it is called by the watcher for the VMThread
3670 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3671 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3672
3673 PcFetcher fetcher(thread);
3674 fetcher.run();
3675 return fetcher.result();
3676 }
3677
3678 ////////////////////////////////////////////////////////////////////////////////
3679 // debug support
3680
3681 bool os::find(address addr, outputStream* st) {
3682 Dl_info dlinfo;
3683 memset(&dlinfo, 0, sizeof(dlinfo));
3684 if (dladdr(addr, &dlinfo) != 0) {
3685 st->print(PTR_FORMAT ": ", addr);
3686 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3687 st->print("%s+%#x", dlinfo.dli_sname,
3688 addr - (intptr_t)dlinfo.dli_saddr);
3689 } else if (dlinfo.dli_fbase != NULL) {
3690 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3691 } else {
3692 st->print("<absolute address>");
3693 }
3694 if (dlinfo.dli_fname != NULL) {
3695 st->print(" in %s", dlinfo.dli_fname);
3696 }
3697 if (dlinfo.dli_fbase != NULL) {
3698 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3699 }
3700 st->cr();
3701
3702 if (Verbose) {
3703 // decode some bytes around the PC
3704 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3705 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3706 address lowest = (address) dlinfo.dli_sname;
3707 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3708 if (begin < lowest) begin = lowest;
3709 Dl_info dlinfo2;
3710 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3711 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3712 end = (address) dlinfo2.dli_saddr;
3713 }
3714 Disassembler::decode(begin, end, st);
3715 }
3716 return true;
3717 }
3718 return false;
3719 }
3720
3721 ////////////////////////////////////////////////////////////////////////////////
3722 // misc
3723
3724 // This does not do anything on Bsd. This is basically a hook for being
3725 // able to use structured exception handling (thread-local exception filters)
3726 // on, e.g., Win32.
3727 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3728 methodHandle* method, JavaCallArguments* args,
3729 Thread* thread) {
3730 f(value, method, args, thread);
3731 }
3732
3733 void os::print_statistics() {
3734 }
3735
3736 int os::message_box(const char* title, const char* message) {
3737 int i;
3738 fdStream err(defaultStream::error_fd());
3739 for (i = 0; i < 78; i++) err.print_raw("=");
3740 err.cr();
3741 err.print_raw_cr(title);
3742 for (i = 0; i < 78; i++) err.print_raw("-");
3743 err.cr();
3744 err.print_raw_cr(message);
3745 for (i = 0; i < 78; i++) err.print_raw("=");
3746 err.cr();
3747
3748 char buf[16];
3749 // Prevent process from exiting upon "read error" without consuming all CPU
3750 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3751
3752 return buf[0] == 'y' || buf[0] == 'Y';
3753 }
3754
3755 int os::stat(const char *path, struct stat *sbuf) {
3756 char pathbuf[MAX_PATH];
3757 if (strlen(path) > MAX_PATH - 1) {
3758 errno = ENAMETOOLONG;
3759 return -1;
3760 }
3761 os::native_path(strcpy(pathbuf, path));
3762 return ::stat(pathbuf, sbuf);
3763 }
3764
3765 bool os::check_heap(bool force) {
3766 return true;
3767 }
3768
3769 // Is a (classpath) directory empty?
3770 bool os::dir_is_empty(const char* path) {
3771 DIR *dir = NULL;
3772 struct dirent *ptr;
3773
3774 dir = opendir(path);
3775 if (dir == NULL) return true;
3776
3777 // Scan the directory
3778 bool result = true;
3779 char buf[sizeof(struct dirent) + MAX_PATH];
3780 while (result && (ptr = ::readdir(dir)) != NULL) {
3781 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3782 result = false;
3783 }
3784 }
3785 closedir(dir);
3786 return result;
3787 }
3788
3789 // This code originates from JDK's sysOpen and open64_w
3790 // from src/solaris/hpi/src/system_md.c
3791
3792 int os::open(const char *path, int oflag, int mode) {
3793 if (strlen(path) > MAX_PATH - 1) {
3794 errno = ENAMETOOLONG;
3795 return -1;
3796 }
3797 int fd;
3798
3799 fd = ::open(path, oflag, mode);
3800 if (fd == -1) return -1;
3801
3802 // If the open succeeded, the file might still be a directory
3803 {
3804 struct stat buf;
3805 int ret = ::fstat(fd, &buf);
3806 int st_mode = buf.st_mode;
3807
3808 if (ret != -1) {
3809 if ((st_mode & S_IFMT) == S_IFDIR) {
3810 errno = EISDIR;
3811 ::close(fd);
3812 return -1;
3813 }
3814 } else {
3815 ::close(fd);
3816 return -1;
3817 }
3818 }
3819
3820 // All file descriptors that are opened in the JVM and not
3821 // specifically destined for a subprocess should have the
3822 // close-on-exec flag set. If we don't set it, then careless 3rd
3823 // party native code might fork and exec without closing all
3824 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3825 // UNIXProcess.c), and this in turn might:
3826 //
3827 // - cause end-of-file to fail to be detected on some file
3828 // descriptors, resulting in mysterious hangs, or
3829 //
3830 // - might cause an fopen in the subprocess to fail on a system
3831 // suffering from bug 1085341.
3832 //
3833 // (Yes, the default setting of the close-on-exec flag is a Unix
3834 // design flaw)
3835 //
3836 // See:
3837 // 1085341: 32-bit stdio routines should support file descriptors >255
3838 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3839 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3840 //
3841 #ifdef FD_CLOEXEC
3842 {
3843 int flags = ::fcntl(fd, F_GETFD);
3844 if (flags != -1) {
3845 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3846 }
3847 }
3848 #endif
3849
3850 return fd;
3851 }
3852
3853
3854 // create binary file, rewriting existing file if required
3855 int os::create_binary_file(const char* path, bool rewrite_existing) {
3856 int oflags = O_WRONLY | O_CREAT;
3857 if (!rewrite_existing) {
3858 oflags |= O_EXCL;
3859 }
3860 return ::open(path, oflags, S_IREAD | S_IWRITE);
3861 }
3862
3863 // return current position of file pointer
3864 jlong os::current_file_offset(int fd) {
3865 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3866 }
3867
3868 // move file pointer to the specified offset
3869 jlong os::seek_to_file_offset(int fd, jlong offset) {
3870 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3871 }
3872
3873 // This code originates from JDK's sysAvailable
3874 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3875
3876 int os::available(int fd, jlong *bytes) {
3877 jlong cur, end;
3878 int mode;
3879 struct stat buf;
3880
3881 if (::fstat(fd, &buf) >= 0) {
3882 mode = buf.st_mode;
3883 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3884 // XXX: is the following call interruptible? If so, this might
3885 // need to go through the INTERRUPT_IO() wrapper as for other
3886 // blocking, interruptible calls in this file.
3887 int n;
3888 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3889 *bytes = n;
3890 return 1;
3891 }
3892 }
3893 }
3894 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3895 return 0;
3896 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3897 return 0;
3898 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3899 return 0;
3900 }
3901 *bytes = end - cur;
3902 return 1;
3903 }
3904
3905 // Map a block of memory.
3906 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3907 char *addr, size_t bytes, bool read_only,
3908 bool allow_exec) {
3909 int prot;
3910 int flags;
3911
3912 if (read_only) {
3913 prot = PROT_READ;
3914 flags = MAP_SHARED;
3915 } else {
3916 prot = PROT_READ | PROT_WRITE;
3917 flags = MAP_PRIVATE;
3918 }
3919
3920 if (allow_exec) {
3921 prot |= PROT_EXEC;
3922 }
3923
3924 if (addr != NULL) {
3925 flags |= MAP_FIXED;
3926 }
3927
3928 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3929 fd, file_offset);
3930 if (mapped_address == MAP_FAILED) {
3931 return NULL;
3932 }
3933 return mapped_address;
3934 }
3935
3936
3937 // Remap a block of memory.
3938 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3939 char *addr, size_t bytes, bool read_only,
3940 bool allow_exec) {
3941 // same as map_memory() on this OS
3942 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3943 allow_exec);
3944 }
3945
3946
3947 // Unmap a block of memory.
3948 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3949 return munmap(addr, bytes) == 0;
3950 }
3951
3952 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3953 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3954 // of a thread.
3955 //
3956 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3957 // the fast estimate available on the platform.
3958
3959 jlong os::current_thread_cpu_time() {
3960 #ifdef __APPLE__
3961 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3962 #else
3963 Unimplemented();
3964 return 0;
3965 #endif
3966 }
3967
3968 jlong os::thread_cpu_time(Thread* thread) {
3969 #ifdef __APPLE__
3970 return os::thread_cpu_time(thread, true /* user + sys */);
3971 #else
3972 Unimplemented();
3973 return 0;
3974 #endif
3975 }
3976
3977 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3978 #ifdef __APPLE__
3979 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3980 #else
3981 Unimplemented();
3982 return 0;
3983 #endif
3984 }
3985
3986 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3987 #ifdef __APPLE__
3988 struct thread_basic_info tinfo;
3989 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3990 kern_return_t kr;
3991 thread_t mach_thread;
3992
3993 mach_thread = thread->osthread()->thread_id();
3994 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3995 if (kr != KERN_SUCCESS) {
3996 return -1;
3997 }
3998
3999 if (user_sys_cpu_time) {
4000 jlong nanos;
4001 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4002 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4003 return nanos;
4004 } else {
4005 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4006 }
4007 #else
4008 Unimplemented();
4009 return 0;
4010 #endif
4011 }
4012
4013
4014 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4015 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4016 info_ptr->may_skip_backward = false; // elapsed time not wall time
4017 info_ptr->may_skip_forward = false; // elapsed time not wall time
4018 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4019 }
4020
4021 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4022 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4023 info_ptr->may_skip_backward = false; // elapsed time not wall time
4024 info_ptr->may_skip_forward = false; // elapsed time not wall time
4025 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4026 }
4027
4028 bool os::is_thread_cpu_time_supported() {
4029 #ifdef __APPLE__
4030 return true;
4031 #else
4032 return false;
4033 #endif
4034 }
4035
4036 // System loadavg support. Returns -1 if load average cannot be obtained.
4037 // Bsd doesn't yet have a (official) notion of processor sets,
4038 // so just return the system wide load average.
4039 int os::loadavg(double loadavg[], int nelem) {
4040 return ::getloadavg(loadavg, nelem);
4041 }
4042
4043 void os::pause() {
4044 char filename[MAX_PATH];
4045 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4046 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4047 } else {
4048 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4049 }
4050
4051 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4052 if (fd != -1) {
4053 struct stat buf;
4054 ::close(fd);
4055 while (::stat(filename, &buf) == 0) {
4056 (void)::poll(NULL, 0, 100);
4057 }
4058 } else {
4059 jio_fprintf(stderr,
4060 "Could not open pause file '%s', continuing immediately.\n", filename);
4061 }
4062 }
4063
4064
4065 // Refer to the comments in os_solaris.cpp park-unpark. The next two
4066 // comment paragraphs are worth repeating here:
4067 //
4068 // Assumption:
4069 // Only one parker can exist on an event, which is why we allocate
4070 // them per-thread. Multiple unparkers can coexist.
4071 //
4072 // _Event serves as a restricted-range semaphore.
4073 // -1 : thread is blocked, i.e. there is a waiter
4074 // 0 : neutral: thread is running or ready,
4075 // could have been signaled after a wait started
4076 // 1 : signaled - thread is running or ready
4077 //
4078 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4079 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4080 // For specifics regarding the bug see GLIBC BUGID 261237 :
4081 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4082 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4083 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4084 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4085 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4086 // and monitorenter when we're using 1-0 locking. All those operations may result in
4087 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4088 // of libpthread avoids the problem, but isn't practical.
4089 //
4090 // Possible remedies:
4091 //
4092 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4093 // This is palliative and probabilistic, however. If the thread is preempted
4094 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4095 // than the minimum period may have passed, and the abstime may be stale (in the
4096 // past) resultin in a hang. Using this technique reduces the odds of a hang
4097 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4098 //
4099 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4100 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4101 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4102 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4103 // thread.
4104 //
4105 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4106 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4107 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4108 // This also works well. In fact it avoids kernel-level scalability impediments
4109 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4110 // timers in a graceful fashion.
4111 //
4112 // 4. When the abstime value is in the past it appears that control returns
4113 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4114 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4115 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4116 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4117 // It may be possible to avoid reinitialization by checking the return
4118 // value from pthread_cond_timedwait(). In addition to reinitializing the
4119 // condvar we must establish the invariant that cond_signal() is only called
4120 // within critical sections protected by the adjunct mutex. This prevents
4121 // cond_signal() from "seeing" a condvar that's in the midst of being
4122 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4123 // desirable signal-after-unlock optimization that avoids futile context switching.
4124 //
4125 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4126 // structure when a condvar is used or initialized. cond_destroy() would
4127 // release the helper structure. Our reinitialize-after-timedwait fix
4128 // put excessive stress on malloc/free and locks protecting the c-heap.
4129 //
4130 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4131 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4132 // and only enabling the work-around for vulnerable environments.
4133
4134 // utility to compute the abstime argument to timedwait:
4135 // millis is the relative timeout time
4136 // abstime will be the absolute timeout time
4137 // TODO: replace compute_abstime() with unpackTime()
4138
4139 static struct timespec* compute_abstime(struct timespec* abstime,
4140 jlong millis) {
4141 if (millis < 0) millis = 0;
4142 struct timeval now;
4143 int status = gettimeofday(&now, NULL);
4144 assert(status == 0, "gettimeofday");
4145 jlong seconds = millis / 1000;
4146 millis %= 1000;
4147 if (seconds > 50000000) { // see man cond_timedwait(3T)
4148 seconds = 50000000;
4149 }
4150 abstime->tv_sec = now.tv_sec + seconds;
4151 long usec = now.tv_usec + millis * 1000;
4152 if (usec >= 1000000) {
4153 abstime->tv_sec += 1;
4154 usec -= 1000000;
4155 }
4156 abstime->tv_nsec = usec * 1000;
4157 return abstime;
4158 }
4159
4160 void os::PlatformEvent::park() { // AKA "down()"
4161 // Transitions for _Event:
4162 // -1 => -1 : illegal
4163 // 1 => 0 : pass - return immediately
4164 // 0 => -1 : block; then set _Event to 0 before returning
4165
4166 // Invariant: Only the thread associated with the Event/PlatformEvent
4167 // may call park().
4168 // TODO: assert that _Assoc != NULL or _Assoc == Self
4169 assert(_nParked == 0, "invariant");
4170
4171 int v;
4172 for (;;) {
4173 v = _Event;
4174 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4175 }
4176 guarantee(v >= 0, "invariant");
4177 if (v == 0) {
4178 // Do this the hard way by blocking ...
4179 int status = pthread_mutex_lock(_mutex);
4180 assert_status(status == 0, status, "mutex_lock");
4181 guarantee(_nParked == 0, "invariant");
4182 ++_nParked;
4183 while (_Event < 0) {
4184 status = pthread_cond_wait(_cond, _mutex);
4185 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4186 // Treat this the same as if the wait was interrupted
4187 if (status == ETIMEDOUT) { status = EINTR; }
4188 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4189 }
4190 --_nParked;
4191
4192 _Event = 0;
4193 status = pthread_mutex_unlock(_mutex);
4194 assert_status(status == 0, status, "mutex_unlock");
4195 // Paranoia to ensure our locked and lock-free paths interact
4196 // correctly with each other.
4197 OrderAccess::fence();
4198 }
4199 guarantee(_Event >= 0, "invariant");
4200 }
4201
4202 int os::PlatformEvent::park(jlong millis) {
4203 // Transitions for _Event:
4204 // -1 => -1 : illegal
4205 // 1 => 0 : pass - return immediately
4206 // 0 => -1 : block; then set _Event to 0 before returning
4207
4208 guarantee(_nParked == 0, "invariant");
4209
4210 int v;
4211 for (;;) {
4212 v = _Event;
4213 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4214 }
4215 guarantee(v >= 0, "invariant");
4216 if (v != 0) return OS_OK;
4217
4218 // We do this the hard way, by blocking the thread.
4219 // Consider enforcing a minimum timeout value.
4220 struct timespec abst;
4221 compute_abstime(&abst, millis);
4222
4223 int ret = OS_TIMEOUT;
4224 int status = pthread_mutex_lock(_mutex);
4225 assert_status(status == 0, status, "mutex_lock");
4226 guarantee(_nParked == 0, "invariant");
4227 ++_nParked;
4228
4229 // Object.wait(timo) will return because of
4230 // (a) notification
4231 // (b) timeout
4232 // (c) thread.interrupt
4233 //
4234 // Thread.interrupt and object.notify{All} both call Event::set.
4235 // That is, we treat thread.interrupt as a special case of notification.
4236 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4237 // We assume all ETIME returns are valid.
4238 //
4239 // TODO: properly differentiate simultaneous notify+interrupt.
4240 // In that case, we should propagate the notify to another waiter.
4241
4242 while (_Event < 0) {
4243 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4244 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4245 pthread_cond_destroy(_cond);
4246 pthread_cond_init(_cond, NULL);
4247 }
4248 assert_status(status == 0 || status == EINTR ||
4249 status == ETIMEDOUT,
4250 status, "cond_timedwait");
4251 if (!FilterSpuriousWakeups) break; // previous semantics
4252 if (status == ETIMEDOUT) break;
4253 // We consume and ignore EINTR and spurious wakeups.
4254 }
4255 --_nParked;
4256 if (_Event >= 0) {
4257 ret = OS_OK;
4258 }
4259 _Event = 0;
4260 status = pthread_mutex_unlock(_mutex);
4261 assert_status(status == 0, status, "mutex_unlock");
4262 assert(_nParked == 0, "invariant");
4263 // Paranoia to ensure our locked and lock-free paths interact
4264 // correctly with each other.
4265 OrderAccess::fence();
4266 return ret;
4267 }
4268
4269 void os::PlatformEvent::unpark() {
4270 // Transitions for _Event:
4271 // 0 => 1 : just return
4272 // 1 => 1 : just return
4273 // -1 => either 0 or 1; must signal target thread
4274 // That is, we can safely transition _Event from -1 to either
4275 // 0 or 1.
4276 // See also: "Semaphores in Plan 9" by Mullender & Cox
4277 //
4278 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4279 // that it will take two back-to-back park() calls for the owning
4280 // thread to block. This has the benefit of forcing a spurious return
4281 // from the first park() call after an unpark() call which will help
4282 // shake out uses of park() and unpark() without condition variables.
4283
4284 if (Atomic::xchg(1, &_Event) >= 0) return;
4285
4286 // Wait for the thread associated with the event to vacate
4287 int status = pthread_mutex_lock(_mutex);
4288 assert_status(status == 0, status, "mutex_lock");
4289 int AnyWaiters = _nParked;
4290 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4291 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4292 AnyWaiters = 0;
4293 pthread_cond_signal(_cond);
4294 }
4295 status = pthread_mutex_unlock(_mutex);
4296 assert_status(status == 0, status, "mutex_unlock");
4297 if (AnyWaiters != 0) {
4298 // Note that we signal() *after* dropping the lock for "immortal" Events.
4299 // This is safe and avoids a common class of futile wakeups. In rare
4300 // circumstances this can cause a thread to return prematurely from
4301 // cond_{timed}wait() but the spurious wakeup is benign and the victim
4302 // will simply re-test the condition and re-park itself.
4303 // This provides particular benefit if the underlying platform does not
4304 // provide wait morphing.
4305 status = pthread_cond_signal(_cond);
4306 assert_status(status == 0, status, "cond_signal");
4307 }
4308 }
4309
4310
4311 // JSR166
4312 // -------------------------------------------------------
4313
4314 // The solaris and bsd implementations of park/unpark are fairly
4315 // conservative for now, but can be improved. They currently use a
4316 // mutex/condvar pair, plus a a count.
4317 // Park decrements count if > 0, else does a condvar wait. Unpark
4318 // sets count to 1 and signals condvar. Only one thread ever waits
4319 // on the condvar. Contention seen when trying to park implies that someone
4320 // is unparking you, so don't wait. And spurious returns are fine, so there
4321 // is no need to track notifications.
4322
4323 #define MAX_SECS 100000000
4324
4325 // This code is common to bsd and solaris and will be moved to a
4326 // common place in dolphin.
4327 //
4328 // The passed in time value is either a relative time in nanoseconds
4329 // or an absolute time in milliseconds. Either way it has to be unpacked
4330 // into suitable seconds and nanoseconds components and stored in the
4331 // given timespec structure.
4332 // Given time is a 64-bit value and the time_t used in the timespec is only
4333 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4334 // overflow if times way in the future are given. Further on Solaris versions
4335 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4336 // number of seconds, in abstime, is less than current_time + 100,000,000.
4337 // As it will be 28 years before "now + 100000000" will overflow we can
4338 // ignore overflow and just impose a hard-limit on seconds using the value
4339 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4340 // years from "now".
4341
4342 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4343 assert(time > 0, "convertTime");
4344
4345 struct timeval now;
4346 int status = gettimeofday(&now, NULL);
4347 assert(status == 0, "gettimeofday");
4348
4349 time_t max_secs = now.tv_sec + MAX_SECS;
4350
4351 if (isAbsolute) {
4352 jlong secs = time / 1000;
4353 if (secs > max_secs) {
4354 absTime->tv_sec = max_secs;
4355 } else {
4356 absTime->tv_sec = secs;
4357 }
4358 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4359 } else {
4360 jlong secs = time / NANOSECS_PER_SEC;
4361 if (secs >= MAX_SECS) {
4362 absTime->tv_sec = max_secs;
4363 absTime->tv_nsec = 0;
4364 } else {
4365 absTime->tv_sec = now.tv_sec + secs;
4366 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4367 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4368 absTime->tv_nsec -= NANOSECS_PER_SEC;
4369 ++absTime->tv_sec; // note: this must be <= max_secs
4370 }
4371 }
4372 }
4373 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4374 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4375 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4376 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4377 }
4378
4379 void Parker::park(bool isAbsolute, jlong time) {
4380 // Ideally we'd do something useful while spinning, such
4381 // as calling unpackTime().
4382
4383 // Optional fast-path check:
4384 // Return immediately if a permit is available.
4385 // We depend on Atomic::xchg() having full barrier semantics
4386 // since we are doing a lock-free update to _counter.
4387 if (Atomic::xchg(0, &_counter) > 0) return;
4388
4389 Thread* thread = Thread::current();
4390 assert(thread->is_Java_thread(), "Must be JavaThread");
4391 JavaThread *jt = (JavaThread *)thread;
4392
4393 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4394 // Check interrupt before trying to wait
4395 if (Thread::is_interrupted(thread, false)) {
4396 return;
4397 }
4398
4399 // Next, demultiplex/decode time arguments
4400 struct timespec absTime;
4401 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4402 return;
4403 }
4404 if (time > 0) {
4405 unpackTime(&absTime, isAbsolute, time);
4406 }
4407
4408
4409 // Enter safepoint region
4410 // Beware of deadlocks such as 6317397.
4411 // The per-thread Parker:: mutex is a classic leaf-lock.
4412 // In particular a thread must never block on the Threads_lock while
4413 // holding the Parker:: mutex. If safepoints are pending both the
4414 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4415 ThreadBlockInVM tbivm(jt);
4416
4417 // Don't wait if cannot get lock since interference arises from
4418 // unblocking. Also. check interrupt before trying wait
4419 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4420 return;
4421 }
4422
4423 int status;
4424 if (_counter > 0) { // no wait needed
4425 _counter = 0;
4426 status = pthread_mutex_unlock(_mutex);
4427 assert(status == 0, "invariant");
4428 // Paranoia to ensure our locked and lock-free paths interact
4429 // correctly with each other and Java-level accesses.
4430 OrderAccess::fence();
4431 return;
4432 }
4433
4434 #ifdef ASSERT
4435 // Don't catch signals while blocked; let the running threads have the signals.
4436 // (This allows a debugger to break into the running thread.)
4437 sigset_t oldsigs;
4438 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4439 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4440 #endif
4441
4442 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4443 jt->set_suspend_equivalent();
4444 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4445
4446 if (time == 0) {
4447 status = pthread_cond_wait(_cond, _mutex);
4448 } else {
4449 status = pthread_cond_timedwait(_cond, _mutex, &absTime);
4450 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4451 pthread_cond_destroy(_cond);
4452 pthread_cond_init(_cond, NULL);
4453 }
4454 }
4455 assert_status(status == 0 || status == EINTR ||
4456 status == ETIMEDOUT,
4457 status, "cond_timedwait");
4458
4459 #ifdef ASSERT
4460 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4461 #endif
4462
4463 _counter = 0;
4464 status = pthread_mutex_unlock(_mutex);
4465 assert_status(status == 0, status, "invariant");
4466 // Paranoia to ensure our locked and lock-free paths interact
4467 // correctly with each other and Java-level accesses.
4468 OrderAccess::fence();
4469
4470 // If externally suspended while waiting, re-suspend
4471 if (jt->handle_special_suspend_equivalent_condition()) {
4472 jt->java_suspend_self();
4473 }
4474 }
4475
4476 void Parker::unpark() {
4477 int status = pthread_mutex_lock(_mutex);
4478 assert(status == 0, "invariant");
4479 const int s = _counter;
4480 _counter = 1;
4481 if (s < 1) {
4482 if (WorkAroundNPTLTimedWaitHang) {
4483 status = pthread_cond_signal(_cond);
4484 assert(status == 0, "invariant");
4485 status = pthread_mutex_unlock(_mutex);
4486 assert(status == 0, "invariant");
4487 } else {
4488 status = pthread_mutex_unlock(_mutex);
4489 assert(status == 0, "invariant");
4490 status = pthread_cond_signal(_cond);
4491 assert(status == 0, "invariant");
4492 }
4493 } else {
4494 pthread_mutex_unlock(_mutex);
4495 assert(status == 0, "invariant");
4496 }
4497 }
4498
4499
4500 // Darwin has no "environ" in a dynamic library.
4501 #ifdef __APPLE__
4502 #include <crt_externs.h>
4503 #define environ (*_NSGetEnviron())
4504 #else
4505 extern char** environ;
4506 #endif
4507
4508 // Run the specified command in a separate process. Return its exit value,
4509 // or -1 on failure (e.g. can't fork a new process).
4510 // Unlike system(), this function can be called from signal handler. It
4511 // doesn't block SIGINT et al.
4512 int os::fork_and_exec(char* cmd) {
4513 const char * argv[4] = {"sh", "-c", cmd, NULL};
4514
4515 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4516 // pthread_atfork handlers and reset pthread library. All we need is a
4517 // separate process to execve. Make a direct syscall to fork process.
4518 // On IA64 there's no fork syscall, we have to use fork() and hope for
4519 // the best...
4520 pid_t pid = fork();
4521
4522 if (pid < 0) {
4523 // fork failed
4524 return -1;
4525
4526 } else if (pid == 0) {
4527 // child process
4528
4529 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4530 // first to kill every thread on the thread list. Because this list is
4531 // not reset by fork() (see notes above), execve() will instead kill
4532 // every thread in the parent process. We know this is the only thread
4533 // in the new process, so make a system call directly.
4534 // IA64 should use normal execve() from glibc to match the glibc fork()
4535 // above.
4536 execve("/bin/sh", (char* const*)argv, environ);
4537
4538 // execve failed
4539 _exit(-1);
4540
4541 } else {
4542 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4543 // care about the actual exit code, for now.
4544
4545 int status;
4546
4547 // Wait for the child process to exit. This returns immediately if
4548 // the child has already exited. */
4549 while (waitpid(pid, &status, 0) < 0) {
4550 switch (errno) {
4551 case ECHILD: return 0;
4552 case EINTR: break;
4553 default: return -1;
4554 }
4555 }
4556
4557 if (WIFEXITED(status)) {
4558 // The child exited normally; get its exit code.
4559 return WEXITSTATUS(status);
4560 } else if (WIFSIGNALED(status)) {
4561 // The child exited because of a signal
4562 // The best value to return is 0x80 + signal number,
4563 // because that is what all Unix shells do, and because
4564 // it allows callers to distinguish between process exit and
4565 // process death by signal.
4566 return 0x80 + WTERMSIG(status);
4567 } else {
4568 // Unknown exit code; pass it through
4569 return status;
4570 }
4571 }
4572 }
4573
4574 // is_headless_jre()
4575 //
4576 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4577 // in order to report if we are running in a headless jre
4578 //
4579 // Since JDK8 xawt/libmawt.so was moved into the same directory
4580 // as libawt.so, and renamed libawt_xawt.so
4581 //
4582 bool os::is_headless_jre() {
4583 #ifdef __APPLE__
4584 // We no longer build headless-only on Mac OS X
4585 return false;
4586 #else
4587 struct stat statbuf;
4588 char buf[MAXPATHLEN];
4589 char libmawtpath[MAXPATHLEN];
4590 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4591 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4592 char *p;
4593
4594 // Get path to libjvm.so
4595 os::jvm_path(buf, sizeof(buf));
4596
4597 // Get rid of libjvm.so
4598 p = strrchr(buf, '/');
4599 if (p == NULL) {
4600 return false;
4601 } else {
4602 *p = '\0';
4603 }
4604
4605 // Get rid of client or server
4606 p = strrchr(buf, '/');
4607 if (p == NULL) {
4608 return false;
4609 } else {
4610 *p = '\0';
4611 }
4612
4613 // check xawt/libmawt.so
4614 strcpy(libmawtpath, buf);
4615 strcat(libmawtpath, xawtstr);
4616 if (::stat(libmawtpath, &statbuf) == 0) return false;
4617
4618 // check libawt_xawt.so
4619 strcpy(libmawtpath, buf);
4620 strcat(libmawtpath, new_xawtstr);
4621 if (::stat(libmawtpath, &statbuf) == 0) return false;
4622
4623 return true;
4624 #endif
4625 }
4626
4627 // Get the default path to the core file
4628 // Returns the length of the string
4629 int os::get_core_path(char* buffer, size_t bufferSize) {
4630 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4631
4632 // Truncate if theoretical string was longer than bufferSize
4633 n = MIN2(n, (int)bufferSize);
4634
4635 return n;
4636 }
4637
4638 #ifndef PRODUCT
4639 void TestReserveMemorySpecial_test() {
4640 // No tests available for this platform
4641 }
4642 #endif