1 /*
2 * Copyright (c) 1999, 2014, 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_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
67
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
103 # include <sys/syscall.h>
104
105 #if defined(__FreeBSD__) || defined(__NetBSD__)
106 # include <elf.h>
107 #endif
108
109 #ifdef __APPLE__
110 # include <mach/mach.h> // semaphore_* API
111 # include <mach-o/dyld.h>
112 # include <sys/proc_info.h>
113 # include <objc/objc-auto.h>
114 #endif
115
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
118 #endif
119
120 #define MAX_PATH (2 * K)
121
122 // for timer info max values which include all bits
123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
124
125 #define LARGEPAGES_BIT (1 << 6)
126 ////////////////////////////////////////////////////////////////////////////////
127 // global variables
128 julong os::Bsd::_physical_memory = 0;
129
130 #ifdef __APPLE__
131 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
132 volatile uint64_t os::Bsd::_max_abstime = 0;
133 #else
134 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
135 #endif
136 pthread_t os::Bsd::_main_thread;
137 int os::Bsd::_page_size = -1;
138
139 static jlong initial_time_count=0;
140
141 static int clock_tics_per_sec = 100;
142
143 // For diagnostics to print a message once. see run_periodic_checks
144 static sigset_t check_signal_done;
145 static bool check_signals = true;
146
147 static pid_t _initial_pid = 0;
148
149 /* Signal number used to suspend/resume a thread */
150
151 /* do not use any signal number less than SIGSEGV, see 4355769 */
152 static int SR_signum = SIGUSR2;
153 sigset_t SR_sigset;
154
155
156 ////////////////////////////////////////////////////////////////////////////////
157 // utility functions
158
159 static int SR_initialize();
160 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
161
162 julong os::available_memory() {
163 return Bsd::available_memory();
164 }
165
166 // available here means free
167 julong os::Bsd::available_memory() {
168 uint64_t available = physical_memory() >> 2;
169 #ifdef __APPLE__
170 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
171 vm_statistics64_data_t vmstat;
172 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
173 (host_info64_t)&vmstat, &count);
174 assert(kerr == KERN_SUCCESS,
175 "host_statistics64 failed - check mach_host_self() and count");
176 if (kerr == KERN_SUCCESS) {
177 available = vmstat.free_count * os::vm_page_size();
178 }
179 #endif
180 return available;
181 }
182
183 julong os::physical_memory() {
184 return Bsd::physical_memory();
185 }
186
187 ////////////////////////////////////////////////////////////////////////////////
188 // environment support
189
190 bool os::getenv(const char* name, char* buf, int len) {
191 const char* val = ::getenv(name);
192 if (val != NULL && strlen(val) < (size_t)len) {
193 strcpy(buf, val);
194 return true;
195 }
196 if (len > 0) buf[0] = 0; // return a null string
197 return false;
198 }
199
200
201 // Return true if user is running as root.
202
203 bool os::have_special_privileges() {
204 static bool init = false;
205 static bool privileges = false;
206 if (!init) {
207 privileges = (getuid() != geteuid()) || (getgid() != getegid());
208 init = true;
209 }
210 return privileges;
211 }
212
213
214
215 // Cpu architecture string
216 #if defined(ZERO)
217 static char cpu_arch[] = ZERO_LIBARCH;
218 #elif defined(IA64)
219 static char cpu_arch[] = "ia64";
220 #elif defined(IA32)
221 static char cpu_arch[] = "i386";
222 #elif defined(AMD64)
223 static char cpu_arch[] = "amd64";
224 #elif defined(ARM)
225 static char cpu_arch[] = "arm";
226 #elif defined(PPC32)
227 static char cpu_arch[] = "ppc";
228 #elif defined(SPARC)
229 # ifdef _LP64
230 static char cpu_arch[] = "sparcv9";
231 # else
232 static char cpu_arch[] = "sparc";
233 # endif
234 #else
235 #error Add appropriate cpu_arch setting
236 #endif
237
238 // Compiler variant
239 #ifdef COMPILER2
240 #define COMPILER_VARIANT "server"
241 #else
242 #define COMPILER_VARIANT "client"
243 #endif
244
245
246 void os::Bsd::initialize_system_info() {
247 int mib[2];
248 size_t len;
249 int cpu_val;
250 julong mem_val;
251
252 /* get processors count via hw.ncpus sysctl */
253 mib[0] = CTL_HW;
254 mib[1] = HW_NCPU;
255 len = sizeof(cpu_val);
256 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
257 assert(len == sizeof(cpu_val), "unexpected data size");
258 set_processor_count(cpu_val);
259 }
260 else {
261 set_processor_count(1); // fallback
262 }
263
264 /* get physical memory via hw.memsize sysctl (hw.memsize is used
265 * since it returns a 64 bit value)
266 */
267 mib[0] = CTL_HW;
268
269 #if defined (HW_MEMSIZE) // Apple
270 mib[1] = HW_MEMSIZE;
271 #elif defined(HW_PHYSMEM) // Most of BSD
272 mib[1] = HW_PHYSMEM;
273 #elif defined(HW_REALMEM) // Old FreeBSD
274 mib[1] = HW_REALMEM;
275 #else
276 #error No ways to get physmem
277 #endif
278
279 len = sizeof(mem_val);
280 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
281 assert(len == sizeof(mem_val), "unexpected data size");
282 _physical_memory = mem_val;
283 } else {
284 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
285 }
286
287 #ifdef __OpenBSD__
288 {
289 // limit _physical_memory memory view on OpenBSD since
290 // datasize rlimit restricts us anyway.
291 struct rlimit limits;
292 getrlimit(RLIMIT_DATA, &limits);
293 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
294 }
295 #endif
296 }
297
298 #ifdef __APPLE__
299 static const char *get_home() {
300 const char *home_dir = ::getenv("HOME");
301 if ((home_dir == NULL) || (*home_dir == '\0')) {
302 struct passwd *passwd_info = getpwuid(geteuid());
303 if (passwd_info != NULL) {
304 home_dir = passwd_info->pw_dir;
305 }
306 }
307
308 return home_dir;
309 }
310 #endif
311
312 void os::init_system_properties_values() {
313 // The next steps are taken in the product version:
314 //
315 // Obtain the JAVA_HOME value from the location of libjvm.so.
316 // This library should be located at:
317 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
318 //
319 // If "/jre/lib/" appears at the right place in the path, then we
320 // assume libjvm.so is installed in a JDK and we use this path.
321 //
322 // Otherwise exit with message: "Could not create the Java virtual machine."
323 //
324 // The following extra steps are taken in the debugging version:
325 //
326 // If "/jre/lib/" does NOT appear at the right place in the path
327 // instead of exit check for $JAVA_HOME environment variable.
328 //
329 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
330 // then we append a fake suffix "hotspot/libjvm.so" to this path so
331 // it looks like libjvm.so is installed there
332 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
333 //
334 // Otherwise exit.
335 //
336 // Important note: if the location of libjvm.so changes this
337 // code needs to be changed accordingly.
338
339 // See ld(1):
340 // The linker uses the following search paths to locate required
341 // shared libraries:
342 // 1: ...
343 // ...
344 // 7: The default directories, normally /lib and /usr/lib.
345 #ifndef DEFAULT_LIBPATH
346 #define DEFAULT_LIBPATH "/lib:/usr/lib"
347 #endif
348
349 // Base path of extensions installed on the system.
350 #define SYS_EXT_DIR "/usr/java/packages"
351 #define EXTENSIONS_DIR "/lib/ext"
352 #define ENDORSED_DIR "/lib/endorsed"
353
354 #ifndef __APPLE__
355
356 // Buffer that fits several sprintfs.
357 // Note that the space for the colon and the trailing null are provided
358 // by the nulls included by the sizeof operator.
359 const size_t bufsize =
360 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends.
361 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir
362 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
363 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
364
365 // sysclasspath, java_home, dll_dir
366 {
367 char *pslash;
368 os::jvm_path(buf, bufsize);
369
370 // Found the full path to libjvm.so.
371 // Now cut the path to <java_home>/jre if we can.
372 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
373 pslash = strrchr(buf, '/');
374 if (pslash != NULL) {
375 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
376 }
377 Arguments::set_dll_dir(buf);
378
379 if (pslash != NULL) {
380 pslash = strrchr(buf, '/');
381 if (pslash != NULL) {
382 *pslash = '\0'; // Get rid of /<arch>.
383 pslash = strrchr(buf, '/');
384 if (pslash != NULL) {
385 *pslash = '\0'; // Get rid of /lib.
386 }
387 }
388 }
389 Arguments::set_java_home(buf);
390 set_boot_path('/', ':');
391 }
392
393 // Where to look for native libraries.
394 //
395 // Note: Due to a legacy implementation, most of the library path
396 // is set in the launcher. This was to accomodate linking restrictions
397 // on legacy Bsd implementations (which are no longer supported).
398 // Eventually, all the library path setting will be done here.
399 //
400 // However, to prevent the proliferation of improperly built native
401 // libraries, the new path component /usr/java/packages is added here.
402 // Eventually, all the library path setting will be done here.
403 {
404 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
405 // should always exist (until the legacy problem cited above is
406 // addressed).
407 const char *v = ::getenv("LD_LIBRARY_PATH");
408 const char *v_colon = ":";
409 if (v == NULL) { v = ""; v_colon = ""; }
410 // That's +1 for the colon and +1 for the trailing '\0'.
411 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
412 strlen(v) + 1 +
413 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
414 mtInternal);
415 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
416 Arguments::set_library_path(ld_library_path);
417 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
418 }
419
420 // Extensions directories.
421 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
422 Arguments::set_ext_dirs(buf);
423
424 // Endorsed standards default directory.
425 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
426 Arguments::set_endorsed_dirs(buf);
427
428 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
429
430 #else // __APPLE__
431
432 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
433 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
434
435 const char *user_home_dir = get_home();
436 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
437 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
438 sizeof(SYS_EXTENSIONS_DIRS);
439
440 // Buffer that fits several sprintfs.
441 // Note that the space for the colon and the trailing null are provided
442 // by the nulls included by the sizeof operator.
443 const size_t bufsize =
444 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends.
445 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir
446 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
447 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
448
449 // sysclasspath, java_home, dll_dir
450 {
451 char *pslash;
452 os::jvm_path(buf, bufsize);
453
454 // Found the full path to libjvm.so.
455 // Now cut the path to <java_home>/jre if we can.
456 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
457 pslash = strrchr(buf, '/');
458 if (pslash != NULL) {
459 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
460 }
461 Arguments::set_dll_dir(buf);
462
463 if (pslash != NULL) {
464 pslash = strrchr(buf, '/');
465 if (pslash != NULL) {
466 *pslash = '\0'; // Get rid of /lib.
467 }
468 }
469 Arguments::set_java_home(buf);
470 set_boot_path('/', ':');
471 }
472
473 // Where to look for native libraries.
474 //
475 // Note: Due to a legacy implementation, most of the library path
476 // is set in the launcher. This was to accomodate linking restrictions
477 // on legacy Bsd implementations (which are no longer supported).
478 // Eventually, all the library path setting will be done here.
479 //
480 // However, to prevent the proliferation of improperly built native
481 // libraries, the new path component /usr/java/packages is added here.
482 // Eventually, all the library path setting will be done here.
483 {
484 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
485 // should always exist (until the legacy problem cited above is
486 // addressed).
487 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
488 // can specify a directory inside an app wrapper
489 const char *l = ::getenv("JAVA_LIBRARY_PATH");
490 const char *l_colon = ":";
491 if (l == NULL) { l = ""; l_colon = ""; }
492
493 const char *v = ::getenv("DYLD_LIBRARY_PATH");
494 const char *v_colon = ":";
495 if (v == NULL) { v = ""; v_colon = ""; }
496
497 // Apple's Java6 has "." at the beginning of java.library.path.
498 // OpenJDK on Windows has "." at the end of java.library.path.
499 // OpenJDK on Linux and Solaris don't have "." in java.library.path
500 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
501 // "." is appended to the end of java.library.path. Yes, this
502 // could cause a change in behavior, but Apple's Java6 behavior
503 // can be achieved by putting "." at the beginning of the
504 // JAVA_LIBRARY_PATH environment variable.
505 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
506 strlen(v) + 1 + strlen(l) + 1 +
507 system_ext_size + 3,
508 mtInternal);
509 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
510 v, v_colon, l, l_colon, user_home_dir);
511 Arguments::set_library_path(ld_library_path);
512 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
513 }
514
515 // Extensions directories.
516 //
517 // Note that the space for the colon and the trailing null are provided
518 // by the nulls included by the sizeof operator (so actually one byte more
519 // than necessary is allocated).
520 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
521 user_home_dir, Arguments::get_java_home());
522 Arguments::set_ext_dirs(buf);
523
524 // Endorsed standards default directory.
525 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
526 Arguments::set_endorsed_dirs(buf);
527
528 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
529
530 #undef SYS_EXTENSIONS_DIR
531 #undef SYS_EXTENSIONS_DIRS
532
533 #endif // __APPLE__
534
535 #undef SYS_EXT_DIR
536 #undef EXTENSIONS_DIR
537 #undef ENDORSED_DIR
538 }
539
540 ////////////////////////////////////////////////////////////////////////////////
541 // breakpoint support
542
543 void os::breakpoint() {
544 BREAKPOINT;
545 }
546
547 extern "C" void breakpoint() {
548 // use debugger to set breakpoint here
549 }
550
551 ////////////////////////////////////////////////////////////////////////////////
552 // signal support
553
554 debug_only(static bool signal_sets_initialized = false);
555 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
556
557 bool os::Bsd::is_sig_ignored(int sig) {
558 struct sigaction oact;
559 sigaction(sig, (struct sigaction*)NULL, &oact);
560 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
561 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
562 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
563 return true;
564 else
565 return false;
566 }
567
568 void os::Bsd::signal_sets_init() {
569 // Should also have an assertion stating we are still single-threaded.
570 assert(!signal_sets_initialized, "Already initialized");
571 // Fill in signals that are necessarily unblocked for all threads in
572 // the VM. Currently, we unblock the following signals:
573 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
574 // by -Xrs (=ReduceSignalUsage));
575 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
576 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
577 // the dispositions or masks wrt these signals.
578 // Programs embedding the VM that want to use the above signals for their
579 // own purposes must, at this time, use the "-Xrs" option to prevent
580 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
581 // (See bug 4345157, and other related bugs).
582 // In reality, though, unblocking these signals is really a nop, since
583 // these signals are not blocked by default.
584 sigemptyset(&unblocked_sigs);
585 sigemptyset(&allowdebug_blocked_sigs);
586 sigaddset(&unblocked_sigs, SIGILL);
587 sigaddset(&unblocked_sigs, SIGSEGV);
588 sigaddset(&unblocked_sigs, SIGBUS);
589 sigaddset(&unblocked_sigs, SIGFPE);
590 sigaddset(&unblocked_sigs, SR_signum);
591
592 if (!ReduceSignalUsage) {
593 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
594 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
595 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
596 }
597 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
598 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
599 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
600 }
601 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
602 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
603 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
604 }
605 }
606 // Fill in signals that are blocked by all but the VM thread.
607 sigemptyset(&vm_sigs);
608 if (!ReduceSignalUsage)
609 sigaddset(&vm_sigs, BREAK_SIGNAL);
610 debug_only(signal_sets_initialized = true);
611
612 }
613
614 // These are signals that are unblocked while a thread is running Java.
615 // (For some reason, they get blocked by default.)
616 sigset_t* os::Bsd::unblocked_signals() {
617 assert(signal_sets_initialized, "Not initialized");
618 return &unblocked_sigs;
619 }
620
621 // These are the signals that are blocked while a (non-VM) thread is
622 // running Java. Only the VM thread handles these signals.
623 sigset_t* os::Bsd::vm_signals() {
624 assert(signal_sets_initialized, "Not initialized");
625 return &vm_sigs;
626 }
627
628 // These are signals that are blocked during cond_wait to allow debugger in
629 sigset_t* os::Bsd::allowdebug_blocked_signals() {
630 assert(signal_sets_initialized, "Not initialized");
631 return &allowdebug_blocked_sigs;
632 }
633
634 void os::Bsd::hotspot_sigmask(Thread* thread) {
635
636 //Save caller's signal mask before setting VM signal mask
637 sigset_t caller_sigmask;
638 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
639
640 OSThread* osthread = thread->osthread();
641 osthread->set_caller_sigmask(caller_sigmask);
642
643 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
644
645 if (!ReduceSignalUsage) {
646 if (thread->is_VM_thread()) {
647 // Only the VM thread handles BREAK_SIGNAL ...
648 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
649 } else {
650 // ... all other threads block BREAK_SIGNAL
651 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
652 }
653 }
654 }
655
656
657 //////////////////////////////////////////////////////////////////////////////
658 // create new thread
659
660 // check if it's safe to start a new thread
661 static bool _thread_safety_check(Thread* thread) {
662 return true;
663 }
664
665 #ifdef __APPLE__
666 // library handle for calling objc_registerThreadWithCollector()
667 // without static linking to the libobjc library
668 #define OBJC_LIB "/usr/lib/libobjc.dylib"
669 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
670 typedef void (*objc_registerThreadWithCollector_t)();
671 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
672 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
673 #endif
674
675 #ifdef __APPLE__
676 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
677 // Additional thread_id used to correlate threads in SA
678 thread_identifier_info_data_t m_ident_info;
679 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
680
681 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
682 (thread_info_t) &m_ident_info, &count);
683
684 return m_ident_info.thread_id;
685 }
686 #endif
687
688 // Thread start routine for all newly created threads
689 static void *java_start(Thread *thread) {
690 // Try to randomize the cache line index of hot stack frames.
691 // This helps when threads of the same stack traces evict each other's
692 // cache lines. The threads can be either from the same JVM instance, or
693 // from different JVM instances. The benefit is especially true for
694 // processors with hyperthreading technology.
695 static int counter = 0;
696 int pid = os::current_process_id();
697 alloca(((pid ^ counter++) & 7) * 128);
698
699 ThreadLocalStorage::set_thread(thread);
700
701 OSThread* osthread = thread->osthread();
702 Monitor* sync = osthread->startThread_lock();
703
704 // non floating stack BsdThreads needs extra check, see above
705 if (!_thread_safety_check(thread)) {
706 // notify parent thread
707 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
708 osthread->set_state(ZOMBIE);
709 sync->notify_all();
710 return NULL;
711 }
712
713 osthread->set_thread_id(os::Bsd::gettid());
714
715 #ifdef __APPLE__
716 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
717 guarantee(unique_thread_id != 0, "unique thread id was not found");
718 osthread->set_unique_thread_id(unique_thread_id);
719 #endif
720 // initialize signal mask for this thread
721 os::Bsd::hotspot_sigmask(thread);
722
723 // initialize floating point control register
724 os::Bsd::init_thread_fpu_state();
725
726 #ifdef __APPLE__
727 // register thread with objc gc
728 if (objc_registerThreadWithCollectorFunction != NULL) {
729 objc_registerThreadWithCollectorFunction();
730 }
731 #endif
732
733 // handshaking with parent thread
734 {
735 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
736
737 // notify parent thread
738 osthread->set_state(INITIALIZED);
739 sync->notify_all();
740
741 // wait until os::start_thread()
742 while (osthread->get_state() == INITIALIZED) {
743 sync->wait(Mutex::_no_safepoint_check_flag);
744 }
745 }
746
747 // call one more level start routine
748 thread->run();
749
750 return 0;
751 }
752
753 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
754 assert(thread->osthread() == NULL, "caller responsible");
755
756 // Allocate the OSThread object
757 OSThread* osthread = new OSThread(NULL, NULL);
758 if (osthread == NULL) {
759 return false;
760 }
761
762 // set the correct thread state
763 osthread->set_thread_type(thr_type);
764
765 // Initial state is ALLOCATED but not INITIALIZED
766 osthread->set_state(ALLOCATED);
767
768 thread->set_osthread(osthread);
769
770 // init thread attributes
771 pthread_attr_t attr;
772 pthread_attr_init(&attr);
773 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
774
775 // stack size
776 if (os::Bsd::supports_variable_stack_size()) {
777 // calculate stack size if it's not specified by caller
778 if (stack_size == 0) {
779 stack_size = os::Bsd::default_stack_size(thr_type);
780
781 switch (thr_type) {
782 case os::java_thread:
783 // Java threads use ThreadStackSize which default value can be
784 // changed with the flag -Xss
785 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
786 stack_size = JavaThread::stack_size_at_create();
787 break;
788 case os::compiler_thread:
789 if (CompilerThreadStackSize > 0) {
790 stack_size = (size_t)(CompilerThreadStackSize * K);
791 break;
792 } // else fall through:
793 // use VMThreadStackSize if CompilerThreadStackSize is not defined
794 case os::vm_thread:
795 case os::pgc_thread:
796 case os::cgc_thread:
797 case os::watcher_thread:
798 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
799 break;
800 }
801 }
802
803 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
804 pthread_attr_setstacksize(&attr, stack_size);
805 } else {
806 // let pthread_create() pick the default value.
807 }
808
809 ThreadState state;
810
811 {
812 pthread_t tid;
813 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
814
815 pthread_attr_destroy(&attr);
816
817 if (ret != 0) {
818 if (PrintMiscellaneous && (Verbose || WizardMode)) {
819 perror("pthread_create()");
820 }
821 // Need to clean up stuff we've allocated so far
822 thread->set_osthread(NULL);
823 delete osthread;
824 return false;
825 }
826
827 // Store pthread info into the OSThread
828 osthread->set_pthread_id(tid);
829
830 // Wait until child thread is either initialized or aborted
831 {
832 Monitor* sync_with_child = osthread->startThread_lock();
833 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
834 while ((state = osthread->get_state()) == ALLOCATED) {
835 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
836 }
837 }
838
839 }
840
841 // Aborted due to thread limit being reached
842 if (state == ZOMBIE) {
843 thread->set_osthread(NULL);
844 delete osthread;
845 return false;
846 }
847
848 // The thread is returned suspended (in state INITIALIZED),
849 // and is started higher up in the call chain
850 assert(state == INITIALIZED, "race condition");
851 return true;
852 }
853
854 /////////////////////////////////////////////////////////////////////////////
855 // attach existing thread
856
857 // bootstrap the main thread
858 bool os::create_main_thread(JavaThread* thread) {
859 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
860 return create_attached_thread(thread);
861 }
862
863 bool os::create_attached_thread(JavaThread* thread) {
864 #ifdef ASSERT
865 thread->verify_not_published();
866 #endif
867
868 // Allocate the OSThread object
869 OSThread* osthread = new OSThread(NULL, NULL);
870
871 if (osthread == NULL) {
872 return false;
873 }
874
875 osthread->set_thread_id(os::Bsd::gettid());
876
877 // Store pthread info into the OSThread
878 #ifdef __APPLE__
879 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
880 guarantee(unique_thread_id != 0, "just checking");
881 osthread->set_unique_thread_id(unique_thread_id);
882 #endif
883 osthread->set_pthread_id(::pthread_self());
884
885 // initialize floating point control register
886 os::Bsd::init_thread_fpu_state();
887
888 // Initial thread state is RUNNABLE
889 osthread->set_state(RUNNABLE);
890
891 thread->set_osthread(osthread);
892
893 // initialize signal mask for this thread
894 // and save the caller's signal mask
895 os::Bsd::hotspot_sigmask(thread);
896
897 return true;
898 }
899
900 void os::pd_start_thread(Thread* thread) {
901 OSThread * osthread = thread->osthread();
902 assert(osthread->get_state() != INITIALIZED, "just checking");
903 Monitor* sync_with_child = osthread->startThread_lock();
904 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
905 sync_with_child->notify();
906 }
907
908 // Free Bsd resources related to the OSThread
909 void os::free_thread(OSThread* osthread) {
910 assert(osthread != NULL, "osthread not set");
911
912 if (Thread::current()->osthread() == osthread) {
913 // Restore caller's signal mask
914 sigset_t sigmask = osthread->caller_sigmask();
915 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
916 }
917
918 delete osthread;
919 }
920
921 //////////////////////////////////////////////////////////////////////////////
922 // thread local storage
923
924 // Restore the thread pointer if the destructor is called. This is in case
925 // someone from JNI code sets up a destructor with pthread_key_create to run
926 // detachCurrentThread on thread death. Unless we restore the thread pointer we
927 // will hang or crash. When detachCurrentThread is called the key will be set
928 // to null and we will not be called again. If detachCurrentThread is never
929 // called we could loop forever depending on the pthread implementation.
930 static void restore_thread_pointer(void* p) {
931 Thread* thread = (Thread*) p;
932 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
933 }
934
935 int os::allocate_thread_local_storage() {
936 pthread_key_t key;
937 int rslt = pthread_key_create(&key, restore_thread_pointer);
938 assert(rslt == 0, "cannot allocate thread local storage");
939 return (int)key;
940 }
941
942 // Note: This is currently not used by VM, as we don't destroy TLS key
943 // on VM exit.
944 void os::free_thread_local_storage(int index) {
945 int rslt = pthread_key_delete((pthread_key_t)index);
946 assert(rslt == 0, "invalid index");
947 }
948
949 void os::thread_local_storage_at_put(int index, void* value) {
950 int rslt = pthread_setspecific((pthread_key_t)index, value);
951 assert(rslt == 0, "pthread_setspecific failed");
952 }
953
954 extern "C" Thread* get_thread() {
955 return ThreadLocalStorage::thread();
956 }
957
958
959 ////////////////////////////////////////////////////////////////////////////////
960 // time support
961
962 // Time since start-up in seconds to a fine granularity.
963 // Used by VMSelfDestructTimer and the MemProfiler.
964 double os::elapsedTime() {
965
966 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
967 }
968
969 jlong os::elapsed_counter() {
970 return javaTimeNanos() - initial_time_count;
971 }
972
973 jlong os::elapsed_frequency() {
974 return NANOSECS_PER_SEC; // nanosecond resolution
975 }
976
977 bool os::supports_vtime() { return true; }
978 bool os::enable_vtime() { return false; }
979 bool os::vtime_enabled() { return false; }
980
981 double os::elapsedVTime() {
982 // better than nothing, but not much
983 return elapsedTime();
984 }
985
986 jlong os::javaTimeMillis() {
987 timeval time;
988 int status = gettimeofday(&time, NULL);
989 assert(status != -1, "bsd error");
990 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
991 }
992
993 #ifndef __APPLE__
994 #ifndef CLOCK_MONOTONIC
995 #define CLOCK_MONOTONIC (1)
996 #endif
997 #endif
998
999 #ifdef __APPLE__
1000 void os::Bsd::clock_init() {
1001 mach_timebase_info(&_timebase_info);
1002 }
1003 #else
1004 void os::Bsd::clock_init() {
1005 struct timespec res;
1006 struct timespec tp;
1007 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
1008 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
1009 // yes, monotonic clock is supported
1010 _clock_gettime = ::clock_gettime;
1011 }
1012 }
1013 #endif
1014
1015
1016
1017 #ifdef __APPLE__
1018
1019 jlong os::javaTimeNanos() {
1020 const uint64_t tm = mach_absolute_time();
1021 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
1022 if (AssumeMonotonicOSTimers) {
1023 return now;
1024 }
1025
1026 const uint64_t prev = Bsd::_max_abstime;
1027 if (now <= prev) {
1028 return prev; // same or retrograde time;
1029 }
1030 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
1031 assert(obsv >= prev, "invariant"); // Monotonicity
1032 // If the CAS succeeded then we're done and return "now".
1033 // If the CAS failed and the observed value "obsv" is >= now then
1034 // we should return "obsv". If the CAS failed and now > obsv > prv then
1035 // some other thread raced this thread and installed a new value, in which case
1036 // we could either (a) retry the entire operation, (b) retry trying to install now
1037 // or (c) just return obsv. We use (c). No loop is required although in some cases
1038 // we might discard a higher "now" value in deference to a slightly lower but freshly
1039 // installed obsv value. That's entirely benign -- it admits no new orderings compared
1040 // to (a) or (b) -- and greatly reduces coherence traffic.
1041 // We might also condition (c) on the magnitude of the delta between obsv and now.
1042 // Avoiding excessive CAS operations to hot RW locations is critical.
1043 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1044 return (prev == obsv) ? now : obsv;
1045 }
1046
1047 #else // __APPLE__
1048
1049 jlong os::javaTimeNanos() {
1050 if (os::supports_monotonic_clock()) {
1051 struct timespec tp;
1052 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1053 assert(status == 0, "gettime error");
1054 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1055 return result;
1056 } else {
1057 timeval time;
1058 int status = gettimeofday(&time, NULL);
1059 assert(status != -1, "bsd error");
1060 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1061 return 1000 * usecs;
1062 }
1063 }
1064
1065 #endif // __APPLE__
1066
1067 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1068 if (os::supports_monotonic_clock()) {
1069 info_ptr->max_value = ALL_64_BITS;
1070
1071 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1072 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1073 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1074 } else {
1075 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1076 info_ptr->max_value = ALL_64_BITS;
1077
1078 // gettimeofday is a real time clock so it skips
1079 info_ptr->may_skip_backward = true;
1080 info_ptr->may_skip_forward = true;
1081 }
1082
1083 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1084 }
1085
1086 // Return the real, user, and system times in seconds from an
1087 // arbitrary fixed point in the past.
1088 bool os::getTimesSecs(double* process_real_time,
1089 double* process_user_time,
1090 double* process_system_time) {
1091 struct tms ticks;
1092 clock_t real_ticks = times(&ticks);
1093
1094 if (real_ticks == (clock_t) (-1)) {
1095 return false;
1096 } else {
1097 double ticks_per_second = (double) clock_tics_per_sec;
1098 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1099 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1100 *process_real_time = ((double) real_ticks) / ticks_per_second;
1101
1102 return true;
1103 }
1104 }
1105
1106
1107 char * os::local_time_string(char *buf, size_t buflen) {
1108 struct tm t;
1109 time_t long_time;
1110 time(&long_time);
1111 localtime_r(&long_time, &t);
1112 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1113 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1114 t.tm_hour, t.tm_min, t.tm_sec);
1115 return buf;
1116 }
1117
1118 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1119 return localtime_r(clock, res);
1120 }
1121
1122 ////////////////////////////////////////////////////////////////////////////////
1123 // runtime exit support
1124
1125 // Note: os::shutdown() might be called very early during initialization, or
1126 // called from signal handler. Before adding something to os::shutdown(), make
1127 // sure it is async-safe and can handle partially initialized VM.
1128 void os::shutdown() {
1129
1130 // allow PerfMemory to attempt cleanup of any persistent resources
1131 perfMemory_exit();
1132
1133 // needs to remove object in file system
1134 AttachListener::abort();
1135
1136 // flush buffered output, finish log files
1137 ostream_abort();
1138
1139 // Check for abort hook
1140 abort_hook_t abort_hook = Arguments::abort_hook();
1141 if (abort_hook != NULL) {
1142 abort_hook();
1143 }
1144
1145 }
1146
1147 // Note: os::abort() might be called very early during initialization, or
1148 // called from signal handler. Before adding something to os::abort(), make
1149 // sure it is async-safe and can handle partially initialized VM.
1150 void os::abort(bool dump_core) {
1151 os::shutdown();
1152 if (dump_core) {
1153 #ifndef PRODUCT
1154 fdStream out(defaultStream::output_fd());
1155 out.print_raw("Current thread is ");
1156 char buf[16];
1157 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1158 out.print_raw_cr(buf);
1159 out.print_raw_cr("Dumping core ...");
1160 #endif
1161 ::abort(); // dump core
1162 }
1163
1164 ::exit(1);
1165 }
1166
1167 // Die immediately, no exit hook, no abort hook, no cleanup.
1168 void os::die() {
1169 // _exit() on BsdThreads only kills current thread
1170 ::abort();
1171 }
1172
1173 // unused on bsd for now.
1174 void os::set_error_file(const char *logfile) {}
1175
1176
1177 // This method is a copy of JDK's sysGetLastErrorString
1178 // from src/solaris/hpi/src/system_md.c
1179
1180 size_t os::lasterror(char *buf, size_t len) {
1181
1182 if (errno == 0) return 0;
1183
1184 const char *s = ::strerror(errno);
1185 size_t n = ::strlen(s);
1186 if (n >= len) {
1187 n = len - 1;
1188 }
1189 ::strncpy(buf, s, n);
1190 buf[n] = '\0';
1191 return n;
1192 }
1193
1194 // Information of current thread in variety of formats
1195 pid_t os::Bsd::gettid() {
1196 int retval = -1;
1197
1198 #ifdef __APPLE__ //XNU kernel
1199 // despite the fact mach port is actually not a thread id use it
1200 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1201 retval = ::pthread_mach_thread_np(::pthread_self());
1202 guarantee(retval != 0, "just checking");
1203 return retval;
1204
1205 #elif __FreeBSD__
1206 retval = syscall(SYS_thr_self);
1207 #elif __OpenBSD__
1208 retval = syscall(SYS_getthrid);
1209 #elif __NetBSD__
1210 retval = (pid_t) syscall(SYS__lwp_self);
1211 #endif
1212
1213 if (retval == -1) {
1214 return getpid();
1215 }
1216 }
1217
1218 intx os::current_thread_id() {
1219 #ifdef __APPLE__
1220 return (intx)::pthread_mach_thread_np(::pthread_self());
1221 #else
1222 return (intx)::pthread_self();
1223 #endif
1224 }
1225
1226 int os::current_process_id() {
1227
1228 // Under the old bsd thread library, bsd gives each thread
1229 // its own process id. Because of this each thread will return
1230 // a different pid if this method were to return the result
1231 // of getpid(2). Bsd provides no api that returns the pid
1232 // of the launcher thread for the vm. This implementation
1233 // returns a unique pid, the pid of the launcher thread
1234 // that starts the vm 'process'.
1235
1236 // Under the NPTL, getpid() returns the same pid as the
1237 // launcher thread rather than a unique pid per thread.
1238 // Use gettid() if you want the old pre NPTL behaviour.
1239
1240 // if you are looking for the result of a call to getpid() that
1241 // returns a unique pid for the calling thread, then look at the
1242 // OSThread::thread_id() method in osThread_bsd.hpp file
1243
1244 return (int)(_initial_pid ? _initial_pid : getpid());
1245 }
1246
1247 // DLL functions
1248
1249 #define JNI_LIB_PREFIX "lib"
1250 #ifdef __APPLE__
1251 #define JNI_LIB_SUFFIX ".dylib"
1252 #else
1253 #define JNI_LIB_SUFFIX ".so"
1254 #endif
1255
1256 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1257
1258 // This must be hard coded because it's the system's temporary
1259 // directory not the java application's temp directory, ala java.io.tmpdir.
1260 #ifdef __APPLE__
1261 // macosx has a secure per-user temporary directory
1262 char temp_path_storage[PATH_MAX];
1263 const char* os::get_temp_directory() {
1264 static char *temp_path = NULL;
1265 if (temp_path == NULL) {
1266 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1267 if (pathSize == 0 || pathSize > PATH_MAX) {
1268 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1269 }
1270 temp_path = temp_path_storage;
1271 }
1272 return temp_path;
1273 }
1274 #else /* __APPLE__ */
1275 const char* os::get_temp_directory() { return "/tmp"; }
1276 #endif /* __APPLE__ */
1277
1278 static bool file_exists(const char* filename) {
1279 struct stat statbuf;
1280 if (filename == NULL || strlen(filename) == 0) {
1281 return false;
1282 }
1283 return os::stat(filename, &statbuf) == 0;
1284 }
1285
1286 bool os::dll_build_name(char* buffer, size_t buflen,
1287 const char* pname, const char* fname) {
1288 bool retval = false;
1289 // Copied from libhpi
1290 const size_t pnamelen = pname ? strlen(pname) : 0;
1291
1292 // Return error on buffer overflow.
1293 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1294 return retval;
1295 }
1296
1297 if (pnamelen == 0) {
1298 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1299 retval = true;
1300 } else if (strchr(pname, *os::path_separator()) != NULL) {
1301 int n;
1302 char** pelements = split_path(pname, &n);
1303 if (pelements == NULL) {
1304 return false;
1305 }
1306 for (int i = 0 ; i < n ; i++) {
1307 // Really shouldn't be NULL, but check can't hurt
1308 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1309 continue; // skip the empty path values
1310 }
1311 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1312 pelements[i], fname);
1313 if (file_exists(buffer)) {
1314 retval = true;
1315 break;
1316 }
1317 }
1318 // release the storage
1319 for (int i = 0 ; i < n ; i++) {
1320 if (pelements[i] != NULL) {
1321 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1322 }
1323 }
1324 if (pelements != NULL) {
1325 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1326 }
1327 } else {
1328 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1329 retval = true;
1330 }
1331 return retval;
1332 }
1333
1334 // check if addr is inside libjvm.so
1335 bool os::address_is_in_vm(address addr) {
1336 static address libjvm_base_addr;
1337 Dl_info dlinfo;
1338
1339 if (libjvm_base_addr == NULL) {
1340 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1341 libjvm_base_addr = (address)dlinfo.dli_fbase;
1342 }
1343 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1344 }
1345
1346 if (dladdr((void *)addr, &dlinfo) != 0) {
1347 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1348 }
1349
1350 return false;
1351 }
1352
1353
1354 #define MACH_MAXSYMLEN 256
1355
1356 bool os::dll_address_to_function_name(address addr, char *buf,
1357 int buflen, int *offset) {
1358 // buf is not optional, but offset is optional
1359 assert(buf != NULL, "sanity check");
1360
1361 Dl_info dlinfo;
1362 char localbuf[MACH_MAXSYMLEN];
1363
1364 if (dladdr((void*)addr, &dlinfo) != 0) {
1365 // see if we have a matching symbol
1366 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1367 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1368 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1369 }
1370 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1371 return true;
1372 }
1373 // no matching symbol so try for just file info
1374 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1375 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1376 buf, buflen, offset, dlinfo.dli_fname)) {
1377 return true;
1378 }
1379 }
1380
1381 // Handle non-dynamic manually:
1382 if (dlinfo.dli_fbase != NULL &&
1383 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1384 dlinfo.dli_fbase)) {
1385 if (!Decoder::demangle(localbuf, buf, buflen)) {
1386 jio_snprintf(buf, buflen, "%s", localbuf);
1387 }
1388 return true;
1389 }
1390 }
1391 buf[0] = '\0';
1392 if (offset != NULL) *offset = -1;
1393 return false;
1394 }
1395
1396 // ported from solaris version
1397 bool os::dll_address_to_library_name(address addr, char* buf,
1398 int buflen, int* offset) {
1399 // buf is not optional, but offset is optional
1400 assert(buf != NULL, "sanity check");
1401
1402 Dl_info dlinfo;
1403
1404 if (dladdr((void*)addr, &dlinfo) != 0) {
1405 if (dlinfo.dli_fname != NULL) {
1406 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1407 }
1408 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1409 *offset = addr - (address)dlinfo.dli_fbase;
1410 }
1411 return true;
1412 }
1413
1414 buf[0] = '\0';
1415 if (offset) *offset = -1;
1416 return false;
1417 }
1418
1419 // Loads .dll/.so and
1420 // in case of error it checks if .dll/.so was built for the
1421 // same architecture as Hotspot is running on
1422
1423 #ifdef __APPLE__
1424 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1425 void * result= ::dlopen(filename, RTLD_LAZY);
1426 if (result != NULL) {
1427 // Successful loading
1428 return result;
1429 }
1430
1431 // Read system error message into ebuf
1432 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1433 ebuf[ebuflen-1]='\0';
1434
1435 return NULL;
1436 }
1437 #else
1438 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1439 {
1440 void * result= ::dlopen(filename, RTLD_LAZY);
1441 if (result != NULL) {
1442 // Successful loading
1443 return result;
1444 }
1445
1446 Elf32_Ehdr elf_head;
1447
1448 // Read system error message into ebuf
1449 // It may or may not be overwritten below
1450 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1451 ebuf[ebuflen-1]='\0';
1452 int diag_msg_max_length=ebuflen-strlen(ebuf);
1453 char* diag_msg_buf=ebuf+strlen(ebuf);
1454
1455 if (diag_msg_max_length==0) {
1456 // No more space in ebuf for additional diagnostics message
1457 return NULL;
1458 }
1459
1460
1461 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1462
1463 if (file_descriptor < 0) {
1464 // Can't open library, report dlerror() message
1465 return NULL;
1466 }
1467
1468 bool failed_to_read_elf_head=
1469 (sizeof(elf_head)!=
1470 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1471
1472 ::close(file_descriptor);
1473 if (failed_to_read_elf_head) {
1474 // file i/o error - report dlerror() msg
1475 return NULL;
1476 }
1477
1478 typedef struct {
1479 Elf32_Half code; // Actual value as defined in elf.h
1480 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1481 char elf_class; // 32 or 64 bit
1482 char endianess; // MSB or LSB
1483 char* name; // String representation
1484 } arch_t;
1485
1486 #ifndef EM_486
1487 #define EM_486 6 /* Intel 80486 */
1488 #endif
1489
1490 #ifndef EM_MIPS_RS3_LE
1491 #define EM_MIPS_RS3_LE 10 /* MIPS */
1492 #endif
1493
1494 #ifndef EM_PPC64
1495 #define EM_PPC64 21 /* PowerPC64 */
1496 #endif
1497
1498 #ifndef EM_S390
1499 #define EM_S390 22 /* IBM System/390 */
1500 #endif
1501
1502 #ifndef EM_IA_64
1503 #define EM_IA_64 50 /* HP/Intel IA-64 */
1504 #endif
1505
1506 #ifndef EM_X86_64
1507 #define EM_X86_64 62 /* AMD x86-64 */
1508 #endif
1509
1510 static const arch_t arch_array[]={
1511 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1512 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1513 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1514 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1515 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1516 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1517 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1518 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1519 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1520 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1521 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1522 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1523 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1524 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1525 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1526 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1527 };
1528
1529 #if (defined IA32)
1530 static Elf32_Half running_arch_code=EM_386;
1531 #elif (defined AMD64)
1532 static Elf32_Half running_arch_code=EM_X86_64;
1533 #elif (defined IA64)
1534 static Elf32_Half running_arch_code=EM_IA_64;
1535 #elif (defined __sparc) && (defined _LP64)
1536 static Elf32_Half running_arch_code=EM_SPARCV9;
1537 #elif (defined __sparc) && (!defined _LP64)
1538 static Elf32_Half running_arch_code=EM_SPARC;
1539 #elif (defined __powerpc64__)
1540 static Elf32_Half running_arch_code=EM_PPC64;
1541 #elif (defined __powerpc__)
1542 static Elf32_Half running_arch_code=EM_PPC;
1543 #elif (defined ARM)
1544 static Elf32_Half running_arch_code=EM_ARM;
1545 #elif (defined S390)
1546 static Elf32_Half running_arch_code=EM_S390;
1547 #elif (defined ALPHA)
1548 static Elf32_Half running_arch_code=EM_ALPHA;
1549 #elif (defined MIPSEL)
1550 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1551 #elif (defined PARISC)
1552 static Elf32_Half running_arch_code=EM_PARISC;
1553 #elif (defined MIPS)
1554 static Elf32_Half running_arch_code=EM_MIPS;
1555 #elif (defined M68K)
1556 static Elf32_Half running_arch_code=EM_68K;
1557 #else
1558 #error Method os::dll_load requires that one of following is defined:\
1559 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1560 #endif
1561
1562 // Identify compatability class for VM's architecture and library's architecture
1563 // Obtain string descriptions for architectures
1564
1565 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1566 int running_arch_index=-1;
1567
1568 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1569 if (running_arch_code == arch_array[i].code) {
1570 running_arch_index = i;
1571 }
1572 if (lib_arch.code == arch_array[i].code) {
1573 lib_arch.compat_class = arch_array[i].compat_class;
1574 lib_arch.name = arch_array[i].name;
1575 }
1576 }
1577
1578 assert(running_arch_index != -1,
1579 "Didn't find running architecture code (running_arch_code) in arch_array");
1580 if (running_arch_index == -1) {
1581 // Even though running architecture detection failed
1582 // we may still continue with reporting dlerror() message
1583 return NULL;
1584 }
1585
1586 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1587 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1588 return NULL;
1589 }
1590
1591 #ifndef S390
1592 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1593 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1594 return NULL;
1595 }
1596 #endif // !S390
1597
1598 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1599 if ( lib_arch.name!=NULL ) {
1600 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1601 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1602 lib_arch.name, arch_array[running_arch_index].name);
1603 } else {
1604 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1605 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1606 lib_arch.code,
1607 arch_array[running_arch_index].name);
1608 }
1609 }
1610
1611 return NULL;
1612 }
1613 #endif /* !__APPLE__ */
1614
1615 void* os::get_default_process_handle() {
1616 #ifdef __APPLE__
1617 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1618 // to avoid finding unexpected symbols on second (or later)
1619 // loads of a library.
1620 return (void*)::dlopen(NULL, RTLD_FIRST);
1621 #else
1622 return (void*)::dlopen(NULL, RTLD_LAZY);
1623 #endif
1624 }
1625
1626 // XXX: Do we need a lock around this as per Linux?
1627 void* os::dll_lookup(void* handle, const char* name) {
1628 return dlsym(handle, name);
1629 }
1630
1631
1632 static bool _print_ascii_file(const char* filename, outputStream* st) {
1633 int fd = ::open(filename, O_RDONLY);
1634 if (fd == -1) {
1635 return false;
1636 }
1637
1638 char buf[32];
1639 int bytes;
1640 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1641 st->print_raw(buf, bytes);
1642 }
1643
1644 ::close(fd);
1645
1646 return true;
1647 }
1648
1649 void os::print_dll_info(outputStream *st) {
1650 st->print_cr("Dynamic libraries:");
1651 #ifdef RTLD_DI_LINKMAP
1652 Dl_info dli;
1653 void *handle;
1654 Link_map *map;
1655 Link_map *p;
1656
1657 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1658 dli.dli_fname == NULL) {
1659 st->print_cr("Error: Cannot print dynamic libraries.");
1660 return;
1661 }
1662 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1663 if (handle == NULL) {
1664 st->print_cr("Error: Cannot print dynamic libraries.");
1665 return;
1666 }
1667 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1668 if (map == NULL) {
1669 st->print_cr("Error: Cannot print dynamic libraries.");
1670 return;
1671 }
1672
1673 while (map->l_prev != NULL)
1674 map = map->l_prev;
1675
1676 while (map != NULL) {
1677 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1678 map = map->l_next;
1679 }
1680
1681 dlclose(handle);
1682 #elif defined(__APPLE__)
1683 uint32_t count;
1684 uint32_t i;
1685
1686 count = _dyld_image_count();
1687 for (i = 1; i < count; i++) {
1688 const char *name = _dyld_get_image_name(i);
1689 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1690 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1691 }
1692 #else
1693 st->print_cr("Error: Cannot print dynamic libraries.");
1694 #endif
1695 }
1696
1697 void os::print_os_info_brief(outputStream* st) {
1698 st->print("Bsd");
1699
1700 os::Posix::print_uname_info(st);
1701 }
1702
1703 void os::print_os_info(outputStream* st) {
1704 st->print("OS:");
1705 st->print("Bsd");
1706
1707 os::Posix::print_uname_info(st);
1708
1709 os::Posix::print_rlimit_info(st);
1710
1711 os::Posix::print_load_average(st);
1712 }
1713
1714 void os::pd_print_cpu_info(outputStream* st) {
1715 // Nothing to do for now.
1716 }
1717
1718 void os::print_memory_info(outputStream* st) {
1719
1720 st->print("Memory:");
1721 st->print(" %dk page", os::vm_page_size()>>10);
1722
1723 st->print(", physical " UINT64_FORMAT "k",
1724 os::physical_memory() >> 10);
1725 st->print("(" UINT64_FORMAT "k free)",
1726 os::available_memory() >> 10);
1727 st->cr();
1728
1729 // meminfo
1730 st->print("\n/proc/meminfo:\n");
1731 _print_ascii_file("/proc/meminfo", st);
1732 st->cr();
1733 }
1734
1735 void os::print_siginfo(outputStream* st, void* siginfo) {
1736 const siginfo_t* si = (const siginfo_t*)siginfo;
1737
1738 os::Posix::print_siginfo_brief(st, si);
1739
1740 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1741 UseSharedSpaces) {
1742 FileMapInfo* mapinfo = FileMapInfo::current_info();
1743 if (mapinfo->is_in_shared_space(si->si_addr)) {
1744 st->print("\n\nError accessing class data sharing archive." \
1745 " Mapped file inaccessible during execution, " \
1746 " possible disk/network problem.");
1747 }
1748 }
1749 st->cr();
1750 }
1751
1752
1753 static void print_signal_handler(outputStream* st, int sig,
1754 char* buf, size_t buflen);
1755
1756 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1757 st->print_cr("Signal Handlers:");
1758 print_signal_handler(st, SIGSEGV, buf, buflen);
1759 print_signal_handler(st, SIGBUS , buf, buflen);
1760 print_signal_handler(st, SIGFPE , buf, buflen);
1761 print_signal_handler(st, SIGPIPE, buf, buflen);
1762 print_signal_handler(st, SIGXFSZ, buf, buflen);
1763 print_signal_handler(st, SIGILL , buf, buflen);
1764 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1765 print_signal_handler(st, SR_signum, buf, buflen);
1766 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1767 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1768 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1769 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1770 }
1771
1772 static char saved_jvm_path[MAXPATHLEN] = {0};
1773
1774 // Find the full path to the current module, libjvm
1775 void os::jvm_path(char *buf, jint buflen) {
1776 // Error checking.
1777 if (buflen < MAXPATHLEN) {
1778 assert(false, "must use a large-enough buffer");
1779 buf[0] = '\0';
1780 return;
1781 }
1782 // Lazy resolve the path to current module.
1783 if (saved_jvm_path[0] != 0) {
1784 strcpy(buf, saved_jvm_path);
1785 return;
1786 }
1787
1788 char dli_fname[MAXPATHLEN];
1789 bool ret = dll_address_to_library_name(
1790 CAST_FROM_FN_PTR(address, os::jvm_path),
1791 dli_fname, sizeof(dli_fname), NULL);
1792 assert(ret, "cannot locate libjvm");
1793 char *rp = NULL;
1794 if (ret && dli_fname[0] != '\0') {
1795 rp = realpath(dli_fname, buf);
1796 }
1797 if (rp == NULL)
1798 return;
1799
1800 if (Arguments::sun_java_launcher_is_altjvm()) {
1801 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1802 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1803 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1804 // appears at the right place in the string, then assume we are
1805 // installed in a JDK and we're done. Otherwise, check for a
1806 // JAVA_HOME environment variable and construct a path to the JVM
1807 // being overridden.
1808
1809 const char *p = buf + strlen(buf) - 1;
1810 for (int count = 0; p > buf && count < 5; ++count) {
1811 for (--p; p > buf && *p != '/'; --p)
1812 /* empty */ ;
1813 }
1814
1815 if (strncmp(p, "/jre/lib/", 9) != 0) {
1816 // Look for JAVA_HOME in the environment.
1817 char* java_home_var = ::getenv("JAVA_HOME");
1818 if (java_home_var != NULL && java_home_var[0] != 0) {
1819 char* jrelib_p;
1820 int len;
1821
1822 // Check the current module name "libjvm"
1823 p = strrchr(buf, '/');
1824 assert(strstr(p, "/libjvm") == p, "invalid library name");
1825
1826 rp = realpath(java_home_var, buf);
1827 if (rp == NULL)
1828 return;
1829
1830 // determine if this is a legacy image or modules image
1831 // modules image doesn't have "jre" subdirectory
1832 len = strlen(buf);
1833 jrelib_p = buf + len;
1834
1835 // Add the appropriate library subdir
1836 snprintf(jrelib_p, buflen-len, "/jre/lib");
1837 if (0 != access(buf, F_OK)) {
1838 snprintf(jrelib_p, buflen-len, "/lib");
1839 }
1840
1841 // Add the appropriate client or server subdir
1842 len = strlen(buf);
1843 jrelib_p = buf + len;
1844 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1845 if (0 != access(buf, F_OK)) {
1846 snprintf(jrelib_p, buflen-len, "%s", "");
1847 }
1848
1849 // If the path exists within JAVA_HOME, add the JVM library name
1850 // to complete the path to JVM being overridden. Otherwise fallback
1851 // to the path to the current library.
1852 if (0 == access(buf, F_OK)) {
1853 // Use current module name "libjvm"
1854 len = strlen(buf);
1855 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1856 } else {
1857 // Fall back to path of current library
1858 rp = realpath(dli_fname, buf);
1859 if (rp == NULL)
1860 return;
1861 }
1862 }
1863 }
1864 }
1865
1866 strcpy(saved_jvm_path, buf);
1867 }
1868
1869 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1870 // no prefix required, not even "_"
1871 }
1872
1873 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1874 // no suffix required
1875 }
1876
1877 ////////////////////////////////////////////////////////////////////////////////
1878 // sun.misc.Signal support
1879
1880 static volatile jint sigint_count = 0;
1881
1882 static void
1883 UserHandler(int sig, void *siginfo, void *context) {
1884 // 4511530 - sem_post is serialized and handled by the manager thread. When
1885 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1886 // don't want to flood the manager thread with sem_post requests.
1887 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1888 return;
1889
1890 // Ctrl-C is pressed during error reporting, likely because the error
1891 // handler fails to abort. Let VM die immediately.
1892 if (sig == SIGINT && is_error_reported()) {
1893 os::die();
1894 }
1895
1896 os::signal_notify(sig);
1897 }
1898
1899 void* os::user_handler() {
1900 return CAST_FROM_FN_PTR(void*, UserHandler);
1901 }
1902
1903 extern "C" {
1904 typedef void (*sa_handler_t)(int);
1905 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1906 }
1907
1908 void* os::signal(int signal_number, void* handler) {
1909 struct sigaction sigAct, oldSigAct;
1910
1911 sigfillset(&(sigAct.sa_mask));
1912 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1913 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1914
1915 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1916 // -1 means registration failed
1917 return (void *)-1;
1918 }
1919
1920 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1921 }
1922
1923 void os::signal_raise(int signal_number) {
1924 ::raise(signal_number);
1925 }
1926
1927 /*
1928 * The following code is moved from os.cpp for making this
1929 * code platform specific, which it is by its very nature.
1930 */
1931
1932 // Will be modified when max signal is changed to be dynamic
1933 int os::sigexitnum_pd() {
1934 return NSIG;
1935 }
1936
1937 // a counter for each possible signal value
1938 static volatile jint pending_signals[NSIG+1] = { 0 };
1939
1940 // Bsd(POSIX) specific hand shaking semaphore.
1941 #ifdef __APPLE__
1942 typedef semaphore_t os_semaphore_t;
1943 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1944 #define SEM_WAIT(sem) semaphore_wait(sem)
1945 #define SEM_POST(sem) semaphore_signal(sem)
1946 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1947 #else
1948 typedef sem_t os_semaphore_t;
1949 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1950 #define SEM_WAIT(sem) sem_wait(&sem)
1951 #define SEM_POST(sem) sem_post(&sem)
1952 #define SEM_DESTROY(sem) sem_destroy(&sem)
1953 #endif
1954
1955 class Semaphore : public StackObj {
1956 public:
1957 Semaphore();
1958 ~Semaphore();
1959 void signal();
1960 void wait();
1961 bool trywait();
1962 bool timedwait(unsigned int sec, int nsec);
1963 private:
1964 jlong currenttime() const;
1965 os_semaphore_t _semaphore;
1966 };
1967
1968 Semaphore::Semaphore() : _semaphore(0) {
1969 SEM_INIT(_semaphore, 0);
1970 }
1971
1972 Semaphore::~Semaphore() {
1973 SEM_DESTROY(_semaphore);
1974 }
1975
1976 void Semaphore::signal() {
1977 SEM_POST(_semaphore);
1978 }
1979
1980 void Semaphore::wait() {
1981 SEM_WAIT(_semaphore);
1982 }
1983
1984 jlong Semaphore::currenttime() const {
1985 struct timeval tv;
1986 gettimeofday(&tv, NULL);
1987 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1988 }
1989
1990 #ifdef __APPLE__
1991 bool Semaphore::trywait() {
1992 return timedwait(0, 0);
1993 }
1994
1995 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1996 kern_return_t kr = KERN_ABORTED;
1997 mach_timespec_t waitspec;
1998 waitspec.tv_sec = sec;
1999 waitspec.tv_nsec = nsec;
2000
2001 jlong starttime = currenttime();
2002
2003 kr = semaphore_timedwait(_semaphore, waitspec);
2004 while (kr == KERN_ABORTED) {
2005 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
2006
2007 jlong current = currenttime();
2008 jlong passedtime = current - starttime;
2009
2010 if (passedtime >= totalwait) {
2011 waitspec.tv_sec = 0;
2012 waitspec.tv_nsec = 0;
2013 } else {
2014 jlong waittime = totalwait - (current - starttime);
2015 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2016 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2017 }
2018
2019 kr = semaphore_timedwait(_semaphore, waitspec);
2020 }
2021
2022 return kr == KERN_SUCCESS;
2023 }
2024
2025 #else
2026
2027 bool Semaphore::trywait() {
2028 return sem_trywait(&_semaphore) == 0;
2029 }
2030
2031 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2032 struct timespec ts;
2033 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2034
2035 while (1) {
2036 int result = sem_timedwait(&_semaphore, &ts);
2037 if (result == 0) {
2038 return true;
2039 } else if (errno == EINTR) {
2040 continue;
2041 } else if (errno == ETIMEDOUT) {
2042 return false;
2043 } else {
2044 return false;
2045 }
2046 }
2047 }
2048
2049 #endif // __APPLE__
2050
2051 static os_semaphore_t sig_sem;
2052 static Semaphore sr_semaphore;
2053
2054 void os::signal_init_pd() {
2055 // Initialize signal structures
2056 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2057
2058 // Initialize signal semaphore
2059 ::SEM_INIT(sig_sem, 0);
2060 }
2061
2062 void os::signal_notify(int sig) {
2063 Atomic::inc(&pending_signals[sig]);
2064 ::SEM_POST(sig_sem);
2065 }
2066
2067 static int check_pending_signals(bool wait) {
2068 Atomic::store(0, &sigint_count);
2069 for (;;) {
2070 for (int i = 0; i < NSIG + 1; i++) {
2071 jint n = pending_signals[i];
2072 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2073 return i;
2074 }
2075 }
2076 if (!wait) {
2077 return -1;
2078 }
2079 JavaThread *thread = JavaThread::current();
2080 ThreadBlockInVM tbivm(thread);
2081
2082 bool threadIsSuspended;
2083 do {
2084 thread->set_suspend_equivalent();
2085 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2086 ::SEM_WAIT(sig_sem);
2087
2088 // were we externally suspended while we were waiting?
2089 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2090 if (threadIsSuspended) {
2091 //
2092 // The semaphore has been incremented, but while we were waiting
2093 // another thread suspended us. We don't want to continue running
2094 // while suspended because that would surprise the thread that
2095 // suspended us.
2096 //
2097 ::SEM_POST(sig_sem);
2098
2099 thread->java_suspend_self();
2100 }
2101 } while (threadIsSuspended);
2102 }
2103 }
2104
2105 int os::signal_lookup() {
2106 return check_pending_signals(false);
2107 }
2108
2109 int os::signal_wait() {
2110 return check_pending_signals(true);
2111 }
2112
2113 ////////////////////////////////////////////////////////////////////////////////
2114 // Virtual Memory
2115
2116 int os::vm_page_size() {
2117 // Seems redundant as all get out
2118 assert(os::Bsd::page_size() != -1, "must call os::init");
2119 return os::Bsd::page_size();
2120 }
2121
2122 // Solaris allocates memory by pages.
2123 int os::vm_allocation_granularity() {
2124 assert(os::Bsd::page_size() != -1, "must call os::init");
2125 return os::Bsd::page_size();
2126 }
2127
2128 // Rationale behind this function:
2129 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2130 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2131 // samples for JITted code. Here we create private executable mapping over the code cache
2132 // and then we can use standard (well, almost, as mapping can change) way to provide
2133 // info for the reporting script by storing timestamp and location of symbol
2134 void bsd_wrap_code(char* base, size_t size) {
2135 static volatile jint cnt = 0;
2136
2137 if (!UseOprofile) {
2138 return;
2139 }
2140
2141 char buf[PATH_MAX + 1];
2142 int num = Atomic::add(1, &cnt);
2143
2144 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2145 os::get_temp_directory(), os::current_process_id(), num);
2146 unlink(buf);
2147
2148 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2149
2150 if (fd != -1) {
2151 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2152 if (rv != (off_t)-1) {
2153 if (::write(fd, "", 1) == 1) {
2154 mmap(base, size,
2155 PROT_READ|PROT_WRITE|PROT_EXEC,
2156 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2157 }
2158 }
2159 ::close(fd);
2160 unlink(buf);
2161 }
2162 }
2163
2164 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2165 int err) {
2166 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2167 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2168 strerror(err), err);
2169 }
2170
2171 // NOTE: Bsd kernel does not really reserve the pages for us.
2172 // All it does is to check if there are enough free pages
2173 // left at the time of mmap(). This could be a potential
2174 // problem.
2175 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2176 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2177 #ifdef __OpenBSD__
2178 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2179 if (::mprotect(addr, size, prot) == 0) {
2180 return true;
2181 }
2182 #else
2183 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2184 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2185 if (res != (uintptr_t) MAP_FAILED) {
2186 return true;
2187 }
2188 #endif
2189
2190 // Warn about any commit errors we see in non-product builds just
2191 // in case mmap() doesn't work as described on the man page.
2192 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2193
2194 return false;
2195 }
2196
2197 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2198 bool exec) {
2199 // alignment_hint is ignored on this OS
2200 return pd_commit_memory(addr, size, exec);
2201 }
2202
2203 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2204 const char* mesg) {
2205 assert(mesg != NULL, "mesg must be specified");
2206 if (!pd_commit_memory(addr, size, exec)) {
2207 // add extra info in product mode for vm_exit_out_of_memory():
2208 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2209 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2210 }
2211 }
2212
2213 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2214 size_t alignment_hint, bool exec,
2215 const char* mesg) {
2216 // alignment_hint is ignored on this OS
2217 pd_commit_memory_or_exit(addr, size, exec, mesg);
2218 }
2219
2220 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2221 }
2222
2223 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2224 ::madvise(addr, bytes, MADV_DONTNEED);
2225 }
2226
2227 void os::numa_make_global(char *addr, size_t bytes) {
2228 }
2229
2230 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2231 }
2232
2233 bool os::numa_topology_changed() { return false; }
2234
2235 size_t os::numa_get_groups_num() {
2236 return 1;
2237 }
2238
2239 int os::numa_get_group_id() {
2240 return 0;
2241 }
2242
2243 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2244 if (size > 0) {
2245 ids[0] = 0;
2246 return 1;
2247 }
2248 return 0;
2249 }
2250
2251 bool os::get_page_info(char *start, page_info* info) {
2252 return false;
2253 }
2254
2255 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2256 return end;
2257 }
2258
2259
2260 bool os::pd_uncommit_memory(char* addr, size_t size) {
2261 #ifdef __OpenBSD__
2262 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2263 return ::mprotect(addr, size, PROT_NONE) == 0;
2264 #else
2265 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2266 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2267 return res != (uintptr_t) MAP_FAILED;
2268 #endif
2269 }
2270
2271 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2272 return os::commit_memory(addr, size, !ExecMem);
2273 }
2274
2275 // If this is a growable mapping, remove the guard pages entirely by
2276 // munmap()ping them. If not, just call uncommit_memory().
2277 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2278 return os::uncommit_memory(addr, size);
2279 }
2280
2281 static address _highest_vm_reserved_address = NULL;
2282
2283 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2284 // at 'requested_addr'. If there are existing memory mappings at the same
2285 // location, however, they will be overwritten. If 'fixed' is false,
2286 // 'requested_addr' is only treated as a hint, the return value may or
2287 // may not start from the requested address. Unlike Bsd mmap(), this
2288 // function returns NULL to indicate failure.
2289 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2290 char * addr;
2291 int flags;
2292
2293 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2294 if (fixed) {
2295 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2296 flags |= MAP_FIXED;
2297 }
2298
2299 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2300 // touch an uncommitted page. Otherwise, the read/write might
2301 // succeed if we have enough swap space to back the physical page.
2302 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2303 flags, -1, 0);
2304
2305 if (addr != MAP_FAILED) {
2306 // anon_mmap() should only get called during VM initialization,
2307 // don't need lock (actually we can skip locking even it can be called
2308 // from multiple threads, because _highest_vm_reserved_address is just a
2309 // hint about the upper limit of non-stack memory regions.)
2310 if ((address)addr + bytes > _highest_vm_reserved_address) {
2311 _highest_vm_reserved_address = (address)addr + bytes;
2312 }
2313 }
2314
2315 return addr == MAP_FAILED ? NULL : addr;
2316 }
2317
2318 // Don't update _highest_vm_reserved_address, because there might be memory
2319 // regions above addr + size. If so, releasing a memory region only creates
2320 // a hole in the address space, it doesn't help prevent heap-stack collision.
2321 //
2322 static int anon_munmap(char * addr, size_t size) {
2323 return ::munmap(addr, size) == 0;
2324 }
2325
2326 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2327 size_t alignment_hint) {
2328 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2329 }
2330
2331 bool os::pd_release_memory(char* addr, size_t size) {
2332 return anon_munmap(addr, size);
2333 }
2334
2335 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2336 // Bsd wants the mprotect address argument to be page aligned.
2337 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2338
2339 // According to SUSv3, mprotect() should only be used with mappings
2340 // established by mmap(), and mmap() always maps whole pages. Unaligned
2341 // 'addr' likely indicates problem in the VM (e.g. trying to change
2342 // protection of malloc'ed or statically allocated memory). Check the
2343 // caller if you hit this assert.
2344 assert(addr == bottom, "sanity check");
2345
2346 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2347 return ::mprotect(bottom, size, prot) == 0;
2348 }
2349
2350 // Set protections specified
2351 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2352 bool is_committed) {
2353 unsigned int p = 0;
2354 switch (prot) {
2355 case MEM_PROT_NONE: p = PROT_NONE; break;
2356 case MEM_PROT_READ: p = PROT_READ; break;
2357 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2358 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2359 default:
2360 ShouldNotReachHere();
2361 }
2362 // is_committed is unused.
2363 return bsd_mprotect(addr, bytes, p);
2364 }
2365
2366 bool os::guard_memory(char* addr, size_t size) {
2367 return bsd_mprotect(addr, size, PROT_NONE);
2368 }
2369
2370 bool os::unguard_memory(char* addr, size_t size) {
2371 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2372 }
2373
2374 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2375 return false;
2376 }
2377
2378 // Large page support
2379
2380 static size_t _large_page_size = 0;
2381
2382 void os::large_page_init() {
2383 }
2384
2385
2386 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2387 fatal("This code is not used or maintained.");
2388
2389 // "exec" is passed in but not used. Creating the shared image for
2390 // the code cache doesn't have an SHM_X executable permission to check.
2391 assert(UseLargePages && UseSHM, "only for SHM large pages");
2392
2393 key_t key = IPC_PRIVATE;
2394 char *addr;
2395
2396 bool warn_on_failure = UseLargePages &&
2397 (!FLAG_IS_DEFAULT(UseLargePages) ||
2398 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2399 );
2400 char msg[128];
2401
2402 // Create a large shared memory region to attach to based on size.
2403 // Currently, size is the total size of the heap
2404 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2405 if (shmid == -1) {
2406 // Possible reasons for shmget failure:
2407 // 1. shmmax is too small for Java heap.
2408 // > check shmmax value: cat /proc/sys/kernel/shmmax
2409 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2410 // 2. not enough large page memory.
2411 // > check available large pages: cat /proc/meminfo
2412 // > increase amount of large pages:
2413 // echo new_value > /proc/sys/vm/nr_hugepages
2414 // Note 1: different Bsd may use different name for this property,
2415 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2416 // Note 2: it's possible there's enough physical memory available but
2417 // they are so fragmented after a long run that they can't
2418 // coalesce into large pages. Try to reserve large pages when
2419 // the system is still "fresh".
2420 if (warn_on_failure) {
2421 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2422 warning(msg);
2423 }
2424 return NULL;
2425 }
2426
2427 // attach to the region
2428 addr = (char*)shmat(shmid, req_addr, 0);
2429 int err = errno;
2430
2431 // Remove shmid. If shmat() is successful, the actual shared memory segment
2432 // will be deleted when it's detached by shmdt() or when the process
2433 // terminates. If shmat() is not successful this will remove the shared
2434 // segment immediately.
2435 shmctl(shmid, IPC_RMID, NULL);
2436
2437 if ((intptr_t)addr == -1) {
2438 if (warn_on_failure) {
2439 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2440 warning(msg);
2441 }
2442 return NULL;
2443 }
2444
2445 // The memory is committed
2446 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2447
2448 return addr;
2449 }
2450
2451 bool os::release_memory_special(char* base, size_t bytes) {
2452 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2453 // detaching the SHM segment will also delete it, see reserve_memory_special()
2454 int rslt = shmdt(base);
2455 if (rslt == 0) {
2456 tkr.record((address)base, bytes);
2457 return true;
2458 } else {
2459 tkr.discard();
2460 return false;
2461 }
2462
2463 }
2464
2465 size_t os::large_page_size() {
2466 return _large_page_size;
2467 }
2468
2469 // HugeTLBFS allows application to commit large page memory on demand;
2470 // with SysV SHM the entire memory region must be allocated as shared
2471 // memory.
2472 bool os::can_commit_large_page_memory() {
2473 return UseHugeTLBFS;
2474 }
2475
2476 bool os::can_execute_large_page_memory() {
2477 return UseHugeTLBFS;
2478 }
2479
2480 // Reserve memory at an arbitrary address, only if that area is
2481 // available (and not reserved for something else).
2482
2483 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2484 const int max_tries = 10;
2485 char* base[max_tries];
2486 size_t size[max_tries];
2487 const size_t gap = 0x000000;
2488
2489 // Assert only that the size is a multiple of the page size, since
2490 // that's all that mmap requires, and since that's all we really know
2491 // about at this low abstraction level. If we need higher alignment,
2492 // we can either pass an alignment to this method or verify alignment
2493 // in one of the methods further up the call chain. See bug 5044738.
2494 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2495
2496 // Repeatedly allocate blocks until the block is allocated at the
2497 // right spot. Give up after max_tries. Note that reserve_memory() will
2498 // automatically update _highest_vm_reserved_address if the call is
2499 // successful. The variable tracks the highest memory address every reserved
2500 // by JVM. It is used to detect heap-stack collision if running with
2501 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2502 // space than needed, it could confuse the collision detecting code. To
2503 // solve the problem, save current _highest_vm_reserved_address and
2504 // calculate the correct value before return.
2505 address old_highest = _highest_vm_reserved_address;
2506
2507 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2508 // if kernel honors the hint then we can return immediately.
2509 char * addr = anon_mmap(requested_addr, bytes, false);
2510 if (addr == requested_addr) {
2511 return requested_addr;
2512 }
2513
2514 if (addr != NULL) {
2515 // mmap() is successful but it fails to reserve at the requested address
2516 anon_munmap(addr, bytes);
2517 }
2518
2519 int i;
2520 for (i = 0; i < max_tries; ++i) {
2521 base[i] = reserve_memory(bytes);
2522
2523 if (base[i] != NULL) {
2524 // Is this the block we wanted?
2525 if (base[i] == requested_addr) {
2526 size[i] = bytes;
2527 break;
2528 }
2529
2530 // Does this overlap the block we wanted? Give back the overlapped
2531 // parts and try again.
2532
2533 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2534 if (top_overlap >= 0 && top_overlap < bytes) {
2535 unmap_memory(base[i], top_overlap);
2536 base[i] += top_overlap;
2537 size[i] = bytes - top_overlap;
2538 } else {
2539 size_t bottom_overlap = base[i] + bytes - requested_addr;
2540 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2541 unmap_memory(requested_addr, bottom_overlap);
2542 size[i] = bytes - bottom_overlap;
2543 } else {
2544 size[i] = bytes;
2545 }
2546 }
2547 }
2548 }
2549
2550 // Give back the unused reserved pieces.
2551
2552 for (int j = 0; j < i; ++j) {
2553 if (base[j] != NULL) {
2554 unmap_memory(base[j], size[j]);
2555 }
2556 }
2557
2558 if (i < max_tries) {
2559 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2560 return requested_addr;
2561 } else {
2562 _highest_vm_reserved_address = old_highest;
2563 return NULL;
2564 }
2565 }
2566
2567 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2568 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2569 }
2570
2571 void os::naked_short_sleep(jlong ms) {
2572 struct timespec req;
2573
2574 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2575 req.tv_sec = 0;
2576 if (ms > 0) {
2577 req.tv_nsec = (ms % 1000) * 1000000;
2578 }
2579 else {
2580 req.tv_nsec = 1;
2581 }
2582
2583 nanosleep(&req, NULL);
2584
2585 return;
2586 }
2587
2588 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2589 void os::infinite_sleep() {
2590 while (true) { // sleep forever ...
2591 ::sleep(100); // ... 100 seconds at a time
2592 }
2593 }
2594
2595 // Used to convert frequent JVM_Yield() to nops
2596 bool os::dont_yield() {
2597 return DontYieldALot;
2598 }
2599
2600 void os::yield() {
2601 sched_yield();
2602 }
2603
2604 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2605
2606 void os::yield_all() {
2607 // Yields to all threads, including threads with lower priorities
2608 // Threads on Bsd are all with same priority. The Solaris style
2609 // os::yield_all() with nanosleep(1ms) is not necessary.
2610 sched_yield();
2611 }
2612
2613 ////////////////////////////////////////////////////////////////////////////////
2614 // thread priority support
2615
2616 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2617 // only supports dynamic priority, static priority must be zero. For real-time
2618 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2619 // However, for large multi-threaded applications, SCHED_RR is not only slower
2620 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2621 // of 5 runs - Sep 2005).
2622 //
2623 // The following code actually changes the niceness of kernel-thread/LWP. It
2624 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2625 // not the entire user process, and user level threads are 1:1 mapped to kernel
2626 // threads. It has always been the case, but could change in the future. For
2627 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2628 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2629
2630 #if !defined(__APPLE__)
2631 int os::java_to_os_priority[CriticalPriority + 1] = {
2632 19, // 0 Entry should never be used
2633
2634 0, // 1 MinPriority
2635 3, // 2
2636 6, // 3
2637
2638 10, // 4
2639 15, // 5 NormPriority
2640 18, // 6
2641
2642 21, // 7
2643 25, // 8
2644 28, // 9 NearMaxPriority
2645
2646 31, // 10 MaxPriority
2647
2648 31 // 11 CriticalPriority
2649 };
2650 #else
2651 /* Using Mach high-level priority assignments */
2652 int os::java_to_os_priority[CriticalPriority + 1] = {
2653 0, // 0 Entry should never be used (MINPRI_USER)
2654
2655 27, // 1 MinPriority
2656 28, // 2
2657 29, // 3
2658
2659 30, // 4
2660 31, // 5 NormPriority (BASEPRI_DEFAULT)
2661 32, // 6
2662
2663 33, // 7
2664 34, // 8
2665 35, // 9 NearMaxPriority
2666
2667 36, // 10 MaxPriority
2668
2669 36 // 11 CriticalPriority
2670 };
2671 #endif
2672
2673 static int prio_init() {
2674 if (ThreadPriorityPolicy == 1) {
2675 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2676 // if effective uid is not root. Perhaps, a more elegant way of doing
2677 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2678 if (geteuid() != 0) {
2679 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2680 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2681 }
2682 ThreadPriorityPolicy = 0;
2683 }
2684 }
2685 if (UseCriticalJavaThreadPriority) {
2686 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2687 }
2688 return 0;
2689 }
2690
2691 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2692 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2693
2694 #ifdef __OpenBSD__
2695 // OpenBSD pthread_setprio starves low priority threads
2696 return OS_OK;
2697 #elif defined(__FreeBSD__)
2698 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2699 #elif defined(__APPLE__) || defined(__NetBSD__)
2700 struct sched_param sp;
2701 int policy;
2702 pthread_t self = pthread_self();
2703
2704 if (pthread_getschedparam(self, &policy, &sp) != 0)
2705 return OS_ERR;
2706
2707 sp.sched_priority = newpri;
2708 if (pthread_setschedparam(self, policy, &sp) != 0)
2709 return OS_ERR;
2710
2711 return OS_OK;
2712 #else
2713 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2714 return (ret == 0) ? OS_OK : OS_ERR;
2715 #endif
2716 }
2717
2718 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2719 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2720 *priority_ptr = java_to_os_priority[NormPriority];
2721 return OS_OK;
2722 }
2723
2724 errno = 0;
2725 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2726 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2727 #elif defined(__APPLE__) || defined(__NetBSD__)
2728 int policy;
2729 struct sched_param sp;
2730
2731 pthread_getschedparam(pthread_self(), &policy, &sp);
2732 *priority_ptr = sp.sched_priority;
2733 #else
2734 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2735 #endif
2736 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2737 }
2738
2739 // Hint to the underlying OS that a task switch would not be good.
2740 // Void return because it's a hint and can fail.
2741 void os::hint_no_preempt() {}
2742
2743 ////////////////////////////////////////////////////////////////////////////////
2744 // suspend/resume support
2745
2746 // the low-level signal-based suspend/resume support is a remnant from the
2747 // old VM-suspension that used to be for java-suspension, safepoints etc,
2748 // within hotspot. Now there is a single use-case for this:
2749 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2750 // that runs in the watcher thread.
2751 // The remaining code is greatly simplified from the more general suspension
2752 // code that used to be used.
2753 //
2754 // The protocol is quite simple:
2755 // - suspend:
2756 // - sends a signal to the target thread
2757 // - polls the suspend state of the osthread using a yield loop
2758 // - target thread signal handler (SR_handler) sets suspend state
2759 // and blocks in sigsuspend until continued
2760 // - resume:
2761 // - sets target osthread state to continue
2762 // - sends signal to end the sigsuspend loop in the SR_handler
2763 //
2764 // Note that the SR_lock plays no role in this suspend/resume protocol.
2765 //
2766
2767 static void resume_clear_context(OSThread *osthread) {
2768 osthread->set_ucontext(NULL);
2769 osthread->set_siginfo(NULL);
2770 }
2771
2772 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2773 osthread->set_ucontext(context);
2774 osthread->set_siginfo(siginfo);
2775 }
2776
2777 //
2778 // Handler function invoked when a thread's execution is suspended or
2779 // resumed. We have to be careful that only async-safe functions are
2780 // called here (Note: most pthread functions are not async safe and
2781 // should be avoided.)
2782 //
2783 // Note: sigwait() is a more natural fit than sigsuspend() from an
2784 // interface point of view, but sigwait() prevents the signal hander
2785 // from being run. libpthread would get very confused by not having
2786 // its signal handlers run and prevents sigwait()'s use with the
2787 // mutex granting granting signal.
2788 //
2789 // Currently only ever called on the VMThread or JavaThread
2790 //
2791 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2792 // Save and restore errno to avoid confusing native code with EINTR
2793 // after sigsuspend.
2794 int old_errno = errno;
2795
2796 Thread* thread = Thread::current();
2797 OSThread* osthread = thread->osthread();
2798 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2799
2800 os::SuspendResume::State current = osthread->sr.state();
2801 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2802 suspend_save_context(osthread, siginfo, context);
2803
2804 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2805 os::SuspendResume::State state = osthread->sr.suspended();
2806 if (state == os::SuspendResume::SR_SUSPENDED) {
2807 sigset_t suspend_set; // signals for sigsuspend()
2808
2809 // get current set of blocked signals and unblock resume signal
2810 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2811 sigdelset(&suspend_set, SR_signum);
2812
2813 sr_semaphore.signal();
2814 // wait here until we are resumed
2815 while (1) {
2816 sigsuspend(&suspend_set);
2817
2818 os::SuspendResume::State result = osthread->sr.running();
2819 if (result == os::SuspendResume::SR_RUNNING) {
2820 sr_semaphore.signal();
2821 break;
2822 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2823 ShouldNotReachHere();
2824 }
2825 }
2826
2827 } else if (state == os::SuspendResume::SR_RUNNING) {
2828 // request was cancelled, continue
2829 } else {
2830 ShouldNotReachHere();
2831 }
2832
2833 resume_clear_context(osthread);
2834 } else if (current == os::SuspendResume::SR_RUNNING) {
2835 // request was cancelled, continue
2836 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2837 // ignore
2838 } else {
2839 // ignore
2840 }
2841
2842 errno = old_errno;
2843 }
2844
2845
2846 static int SR_initialize() {
2847 struct sigaction act;
2848 char *s;
2849 /* Get signal number to use for suspend/resume */
2850 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2851 int sig = ::strtol(s, 0, 10);
2852 if (sig > 0 || sig < NSIG) {
2853 SR_signum = sig;
2854 }
2855 }
2856
2857 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2858 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2859
2860 sigemptyset(&SR_sigset);
2861 sigaddset(&SR_sigset, SR_signum);
2862
2863 /* Set up signal handler for suspend/resume */
2864 act.sa_flags = SA_RESTART|SA_SIGINFO;
2865 act.sa_handler = (void (*)(int)) SR_handler;
2866
2867 // SR_signum is blocked by default.
2868 // 4528190 - We also need to block pthread restart signal (32 on all
2869 // supported Bsd platforms). Note that BsdThreads need to block
2870 // this signal for all threads to work properly. So we don't have
2871 // to use hard-coded signal number when setting up the mask.
2872 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2873
2874 if (sigaction(SR_signum, &act, 0) == -1) {
2875 return -1;
2876 }
2877
2878 // Save signal flag
2879 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2880 return 0;
2881 }
2882
2883 static int sr_notify(OSThread* osthread) {
2884 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2885 assert_status(status == 0, status, "pthread_kill");
2886 return status;
2887 }
2888
2889 // "Randomly" selected value for how long we want to spin
2890 // before bailing out on suspending a thread, also how often
2891 // we send a signal to a thread we want to resume
2892 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2893 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2894
2895 // returns true on success and false on error - really an error is fatal
2896 // but this seems the normal response to library errors
2897 static bool do_suspend(OSThread* osthread) {
2898 assert(osthread->sr.is_running(), "thread should be running");
2899 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2900
2901 // mark as suspended and send signal
2902 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2903 // failed to switch, state wasn't running?
2904 ShouldNotReachHere();
2905 return false;
2906 }
2907
2908 if (sr_notify(osthread) != 0) {
2909 ShouldNotReachHere();
2910 }
2911
2912 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2913 while (true) {
2914 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2915 break;
2916 } else {
2917 // timeout
2918 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2919 if (cancelled == os::SuspendResume::SR_RUNNING) {
2920 return false;
2921 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2922 // make sure that we consume the signal on the semaphore as well
2923 sr_semaphore.wait();
2924 break;
2925 } else {
2926 ShouldNotReachHere();
2927 return false;
2928 }
2929 }
2930 }
2931
2932 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2933 return true;
2934 }
2935
2936 static void do_resume(OSThread* osthread) {
2937 assert(osthread->sr.is_suspended(), "thread should be suspended");
2938 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2939
2940 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2941 // failed to switch to WAKEUP_REQUEST
2942 ShouldNotReachHere();
2943 return;
2944 }
2945
2946 while (true) {
2947 if (sr_notify(osthread) == 0) {
2948 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2949 if (osthread->sr.is_running()) {
2950 return;
2951 }
2952 }
2953 } else {
2954 ShouldNotReachHere();
2955 }
2956 }
2957
2958 guarantee(osthread->sr.is_running(), "Must be running!");
2959 }
2960
2961 ///////////////////////////////////////////////////////////////////////////////////
2962 // signal handling (except suspend/resume)
2963
2964 // This routine may be used by user applications as a "hook" to catch signals.
2965 // The user-defined signal handler must pass unrecognized signals to this
2966 // routine, and if it returns true (non-zero), then the signal handler must
2967 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2968 // routine will never retun false (zero), but instead will execute a VM panic
2969 // routine kill the process.
2970 //
2971 // If this routine returns false, it is OK to call it again. This allows
2972 // the user-defined signal handler to perform checks either before or after
2973 // the VM performs its own checks. Naturally, the user code would be making
2974 // a serious error if it tried to handle an exception (such as a null check
2975 // or breakpoint) that the VM was generating for its own correct operation.
2976 //
2977 // This routine may recognize any of the following kinds of signals:
2978 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2979 // It should be consulted by handlers for any of those signals.
2980 //
2981 // The caller of this routine must pass in the three arguments supplied
2982 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2983 // field of the structure passed to sigaction(). This routine assumes that
2984 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2985 //
2986 // Note that the VM will print warnings if it detects conflicting signal
2987 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2988 //
2989 extern "C" JNIEXPORT int
2990 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2991 void* ucontext, int abort_if_unrecognized);
2992
2993 void signalHandler(int sig, siginfo_t* info, void* uc) {
2994 assert(info != NULL && uc != NULL, "it must be old kernel");
2995 int orig_errno = errno; // Preserve errno value over signal handler.
2996 JVM_handle_bsd_signal(sig, info, uc, true);
2997 errno = orig_errno;
2998 }
2999
3000
3001 // This boolean allows users to forward their own non-matching signals
3002 // to JVM_handle_bsd_signal, harmlessly.
3003 bool os::Bsd::signal_handlers_are_installed = false;
3004
3005 // For signal-chaining
3006 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3007 unsigned int os::Bsd::sigs = 0;
3008 bool os::Bsd::libjsig_is_loaded = false;
3009 typedef struct sigaction *(*get_signal_t)(int);
3010 get_signal_t os::Bsd::get_signal_action = NULL;
3011
3012 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3013 struct sigaction *actp = NULL;
3014
3015 if (libjsig_is_loaded) {
3016 // Retrieve the old signal handler from libjsig
3017 actp = (*get_signal_action)(sig);
3018 }
3019 if (actp == NULL) {
3020 // Retrieve the preinstalled signal handler from jvm
3021 actp = get_preinstalled_handler(sig);
3022 }
3023
3024 return actp;
3025 }
3026
3027 static bool call_chained_handler(struct sigaction *actp, int sig,
3028 siginfo_t *siginfo, void *context) {
3029 // Call the old signal handler
3030 if (actp->sa_handler == SIG_DFL) {
3031 // It's more reasonable to let jvm treat it as an unexpected exception
3032 // instead of taking the default action.
3033 return false;
3034 } else if (actp->sa_handler != SIG_IGN) {
3035 if ((actp->sa_flags & SA_NODEFER) == 0) {
3036 // automaticlly block the signal
3037 sigaddset(&(actp->sa_mask), sig);
3038 }
3039
3040 sa_handler_t hand;
3041 sa_sigaction_t sa;
3042 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3043 // retrieve the chained handler
3044 if (siginfo_flag_set) {
3045 sa = actp->sa_sigaction;
3046 } else {
3047 hand = actp->sa_handler;
3048 }
3049
3050 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3051 actp->sa_handler = SIG_DFL;
3052 }
3053
3054 // try to honor the signal mask
3055 sigset_t oset;
3056 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3057
3058 // call into the chained handler
3059 if (siginfo_flag_set) {
3060 (*sa)(sig, siginfo, context);
3061 } else {
3062 (*hand)(sig);
3063 }
3064
3065 // restore the signal mask
3066 pthread_sigmask(SIG_SETMASK, &oset, 0);
3067 }
3068 // Tell jvm's signal handler the signal is taken care of.
3069 return true;
3070 }
3071
3072 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3073 bool chained = false;
3074 // signal-chaining
3075 if (UseSignalChaining) {
3076 struct sigaction *actp = get_chained_signal_action(sig);
3077 if (actp != NULL) {
3078 chained = call_chained_handler(actp, sig, siginfo, context);
3079 }
3080 }
3081 return chained;
3082 }
3083
3084 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3085 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3086 return &sigact[sig];
3087 }
3088 return NULL;
3089 }
3090
3091 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3092 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3093 sigact[sig] = oldAct;
3094 sigs |= (unsigned int)1 << sig;
3095 }
3096
3097 // for diagnostic
3098 int os::Bsd::sigflags[MAXSIGNUM];
3099
3100 int os::Bsd::get_our_sigflags(int sig) {
3101 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3102 return sigflags[sig];
3103 }
3104
3105 void os::Bsd::set_our_sigflags(int sig, int flags) {
3106 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3107 sigflags[sig] = flags;
3108 }
3109
3110 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3111 // Check for overwrite.
3112 struct sigaction oldAct;
3113 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3114
3115 void* oldhand = oldAct.sa_sigaction
3116 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3117 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3118 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3119 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3120 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3121 if (AllowUserSignalHandlers || !set_installed) {
3122 // Do not overwrite; user takes responsibility to forward to us.
3123 return;
3124 } else if (UseSignalChaining) {
3125 // save the old handler in jvm
3126 save_preinstalled_handler(sig, oldAct);
3127 // libjsig also interposes the sigaction() call below and saves the
3128 // old sigaction on it own.
3129 } else {
3130 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3131 "%#lx for signal %d.", (long)oldhand, sig));
3132 }
3133 }
3134
3135 struct sigaction sigAct;
3136 sigfillset(&(sigAct.sa_mask));
3137 sigAct.sa_handler = SIG_DFL;
3138 if (!set_installed) {
3139 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3140 } else {
3141 sigAct.sa_sigaction = signalHandler;
3142 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3143 }
3144 #ifdef __APPLE__
3145 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3146 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3147 // if the signal handler declares it will handle it on alternate stack.
3148 // Notice we only declare we will handle it on alt stack, but we are not
3149 // actually going to use real alt stack - this is just a workaround.
3150 // Please see ux_exception.c, method catch_mach_exception_raise for details
3151 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3152 if (sig == SIGSEGV) {
3153 sigAct.sa_flags |= SA_ONSTACK;
3154 }
3155 #endif
3156
3157 // Save flags, which are set by ours
3158 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3159 sigflags[sig] = sigAct.sa_flags;
3160
3161 int ret = sigaction(sig, &sigAct, &oldAct);
3162 assert(ret == 0, "check");
3163
3164 void* oldhand2 = oldAct.sa_sigaction
3165 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3166 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3167 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3168 }
3169
3170 // install signal handlers for signals that HotSpot needs to
3171 // handle in order to support Java-level exception handling.
3172
3173 void os::Bsd::install_signal_handlers() {
3174 if (!signal_handlers_are_installed) {
3175 signal_handlers_are_installed = true;
3176
3177 // signal-chaining
3178 typedef void (*signal_setting_t)();
3179 signal_setting_t begin_signal_setting = NULL;
3180 signal_setting_t end_signal_setting = NULL;
3181 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3182 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3183 if (begin_signal_setting != NULL) {
3184 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3185 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3186 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3187 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3188 libjsig_is_loaded = true;
3189 assert(UseSignalChaining, "should enable signal-chaining");
3190 }
3191 if (libjsig_is_loaded) {
3192 // Tell libjsig jvm is setting signal handlers
3193 (*begin_signal_setting)();
3194 }
3195
3196 set_signal_handler(SIGSEGV, true);
3197 set_signal_handler(SIGPIPE, true);
3198 set_signal_handler(SIGBUS, true);
3199 set_signal_handler(SIGILL, true);
3200 set_signal_handler(SIGFPE, true);
3201 set_signal_handler(SIGXFSZ, true);
3202
3203 #if defined(__APPLE__)
3204 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3205 // signals caught and handled by the JVM. To work around this, we reset the mach task
3206 // signal handler that's placed on our process by CrashReporter. This disables
3207 // CrashReporter-based reporting.
3208 //
3209 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3210 // on caught fatal signals.
3211 //
3212 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3213 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3214 // exception handling, while leaving the standard BSD signal handlers functional.
3215 kern_return_t kr;
3216 kr = task_set_exception_ports(mach_task_self(),
3217 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3218 MACH_PORT_NULL,
3219 EXCEPTION_STATE_IDENTITY,
3220 MACHINE_THREAD_STATE);
3221
3222 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3223 #endif
3224
3225 if (libjsig_is_loaded) {
3226 // Tell libjsig jvm finishes setting signal handlers
3227 (*end_signal_setting)();
3228 }
3229
3230 // We don't activate signal checker if libjsig is in place, we trust ourselves
3231 // and if UserSignalHandler is installed all bets are off
3232 if (CheckJNICalls) {
3233 if (libjsig_is_loaded) {
3234 if (PrintJNIResolving) {
3235 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3236 }
3237 check_signals = false;
3238 }
3239 if (AllowUserSignalHandlers) {
3240 if (PrintJNIResolving) {
3241 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3242 }
3243 check_signals = false;
3244 }
3245 }
3246 }
3247 }
3248
3249
3250 /////
3251 // glibc on Bsd platform uses non-documented flag
3252 // to indicate, that some special sort of signal
3253 // trampoline is used.
3254 // We will never set this flag, and we should
3255 // ignore this flag in our diagnostic
3256 #ifdef SIGNIFICANT_SIGNAL_MASK
3257 #undef SIGNIFICANT_SIGNAL_MASK
3258 #endif
3259 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3260
3261 static const char* get_signal_handler_name(address handler,
3262 char* buf, int buflen) {
3263 int offset;
3264 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3265 if (found) {
3266 // skip directory names
3267 const char *p1, *p2;
3268 p1 = buf;
3269 size_t len = strlen(os::file_separator());
3270 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3271 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3272 } else {
3273 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3274 }
3275 return buf;
3276 }
3277
3278 static void print_signal_handler(outputStream* st, int sig,
3279 char* buf, size_t buflen) {
3280 struct sigaction sa;
3281
3282 sigaction(sig, NULL, &sa);
3283
3284 // See comment for SIGNIFICANT_SIGNAL_MASK define
3285 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3286
3287 st->print("%s: ", os::exception_name(sig, buf, buflen));
3288
3289 address handler = (sa.sa_flags & SA_SIGINFO)
3290 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3291 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3292
3293 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3294 st->print("SIG_DFL");
3295 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3296 st->print("SIG_IGN");
3297 } else {
3298 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3299 }
3300
3301 st->print(", sa_mask[0]=");
3302 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3303
3304 address rh = VMError::get_resetted_sighandler(sig);
3305 // May be, handler was resetted by VMError?
3306 if(rh != NULL) {
3307 handler = rh;
3308 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3309 }
3310
3311 st->print(", sa_flags=");
3312 os::Posix::print_sa_flags(st, sa.sa_flags);
3313
3314 // Check: is it our handler?
3315 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3316 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3317 // It is our signal handler
3318 // check for flags, reset system-used one!
3319 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3320 st->print(
3321 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3322 os::Bsd::get_our_sigflags(sig));
3323 }
3324 }
3325 st->cr();
3326 }
3327
3328
3329 #define DO_SIGNAL_CHECK(sig) \
3330 if (!sigismember(&check_signal_done, sig)) \
3331 os::Bsd::check_signal_handler(sig)
3332
3333 // This method is a periodic task to check for misbehaving JNI applications
3334 // under CheckJNI, we can add any periodic checks here
3335
3336 void os::run_periodic_checks() {
3337
3338 if (check_signals == false) return;
3339
3340 // SEGV and BUS if overridden could potentially prevent
3341 // generation of hs*.log in the event of a crash, debugging
3342 // such a case can be very challenging, so we absolutely
3343 // check the following for a good measure:
3344 DO_SIGNAL_CHECK(SIGSEGV);
3345 DO_SIGNAL_CHECK(SIGILL);
3346 DO_SIGNAL_CHECK(SIGFPE);
3347 DO_SIGNAL_CHECK(SIGBUS);
3348 DO_SIGNAL_CHECK(SIGPIPE);
3349 DO_SIGNAL_CHECK(SIGXFSZ);
3350
3351
3352 // ReduceSignalUsage allows the user to override these handlers
3353 // see comments at the very top and jvm_solaris.h
3354 if (!ReduceSignalUsage) {
3355 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3356 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3357 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3358 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3359 }
3360
3361 DO_SIGNAL_CHECK(SR_signum);
3362 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3363 }
3364
3365 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3366
3367 static os_sigaction_t os_sigaction = NULL;
3368
3369 void os::Bsd::check_signal_handler(int sig) {
3370 char buf[O_BUFLEN];
3371 address jvmHandler = NULL;
3372
3373
3374 struct sigaction act;
3375 if (os_sigaction == NULL) {
3376 // only trust the default sigaction, in case it has been interposed
3377 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3378 if (os_sigaction == NULL) return;
3379 }
3380
3381 os_sigaction(sig, (struct sigaction*)NULL, &act);
3382
3383
3384 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3385
3386 address thisHandler = (act.sa_flags & SA_SIGINFO)
3387 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3388 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3389
3390
3391 switch(sig) {
3392 case SIGSEGV:
3393 case SIGBUS:
3394 case SIGFPE:
3395 case SIGPIPE:
3396 case SIGILL:
3397 case SIGXFSZ:
3398 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3399 break;
3400
3401 case SHUTDOWN1_SIGNAL:
3402 case SHUTDOWN2_SIGNAL:
3403 case SHUTDOWN3_SIGNAL:
3404 case BREAK_SIGNAL:
3405 jvmHandler = (address)user_handler();
3406 break;
3407
3408 case INTERRUPT_SIGNAL:
3409 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3410 break;
3411
3412 default:
3413 if (sig == SR_signum) {
3414 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3415 } else {
3416 return;
3417 }
3418 break;
3419 }
3420
3421 if (thisHandler != jvmHandler) {
3422 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3423 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3424 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3425 // No need to check this sig any longer
3426 sigaddset(&check_signal_done, sig);
3427 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3428 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3429 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3430 exception_name(sig, buf, O_BUFLEN));
3431 }
3432 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3433 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3434 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3435 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3436 // No need to check this sig any longer
3437 sigaddset(&check_signal_done, sig);
3438 }
3439
3440 // Dump all the signal
3441 if (sigismember(&check_signal_done, sig)) {
3442 print_signal_handlers(tty, buf, O_BUFLEN);
3443 }
3444 }
3445
3446 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3447
3448 extern bool signal_name(int signo, char* buf, size_t len);
3449
3450 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3451 if (0 < exception_code && exception_code <= SIGRTMAX) {
3452 // signal
3453 if (!signal_name(exception_code, buf, size)) {
3454 jio_snprintf(buf, size, "SIG%d", exception_code);
3455 }
3456 return buf;
3457 } else {
3458 return NULL;
3459 }
3460 }
3461
3462 // this is called _before_ the most of global arguments have been parsed
3463 void os::init(void) {
3464 char dummy; /* used to get a guess on initial stack address */
3465 // first_hrtime = gethrtime();
3466
3467 // With BsdThreads the JavaMain thread pid (primordial thread)
3468 // is different than the pid of the java launcher thread.
3469 // So, on Bsd, the launcher thread pid is passed to the VM
3470 // via the sun.java.launcher.pid property.
3471 // Use this property instead of getpid() if it was correctly passed.
3472 // See bug 6351349.
3473 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3474
3475 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3476
3477 clock_tics_per_sec = CLK_TCK;
3478
3479 init_random(1234567);
3480
3481 ThreadCritical::initialize();
3482
3483 Bsd::set_page_size(getpagesize());
3484 if (Bsd::page_size() == -1) {
3485 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3486 strerror(errno)));
3487 }
3488 init_page_sizes((size_t) Bsd::page_size());
3489
3490 Bsd::initialize_system_info();
3491
3492 // main_thread points to the aboriginal thread
3493 Bsd::_main_thread = pthread_self();
3494
3495 Bsd::clock_init();
3496 initial_time_count = javaTimeNanos();
3497
3498 #ifdef __APPLE__
3499 // XXXDARWIN
3500 // Work around the unaligned VM callbacks in hotspot's
3501 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3502 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3503 // alignment when doing symbol lookup. To work around this, we force early
3504 // binding of all symbols now, thus binding when alignment is known-good.
3505 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3506 #endif
3507 }
3508
3509 // To install functions for atexit system call
3510 extern "C" {
3511 static void perfMemory_exit_helper() {
3512 perfMemory_exit();
3513 }
3514 }
3515
3516 // this is called _after_ the global arguments have been parsed
3517 jint os::init_2(void)
3518 {
3519 // Allocate a single page and mark it as readable for safepoint polling
3520 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3521 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3522
3523 os::set_polling_page( polling_page );
3524
3525 #ifndef PRODUCT
3526 if(Verbose && PrintMiscellaneous)
3527 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3528 #endif
3529
3530 if (!UseMembar) {
3531 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3532 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3533 os::set_memory_serialize_page( mem_serialize_page );
3534
3535 #ifndef PRODUCT
3536 if(Verbose && PrintMiscellaneous)
3537 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3538 #endif
3539 }
3540
3541 // initialize suspend/resume support - must do this before signal_sets_init()
3542 if (SR_initialize() != 0) {
3543 perror("SR_initialize failed");
3544 return JNI_ERR;
3545 }
3546
3547 Bsd::signal_sets_init();
3548 Bsd::install_signal_handlers();
3549
3550 // Check minimum allowable stack size for thread creation and to initialize
3551 // the java system classes, including StackOverflowError - depends on page
3552 // size. Add a page for compiler2 recursion in main thread.
3553 // Add in 2*BytesPerWord times page size to account for VM stack during
3554 // class initialization depending on 32 or 64 bit VM.
3555 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3556 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3557 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3558
3559 size_t threadStackSizeInBytes = ThreadStackSize * K;
3560 if (threadStackSizeInBytes != 0 &&
3561 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3562 tty->print_cr("\nThe stack size specified is too small, "
3563 "Specify at least %dk",
3564 os::Bsd::min_stack_allowed/ K);
3565 return JNI_ERR;
3566 }
3567
3568 // Make the stack size a multiple of the page size so that
3569 // the yellow/red zones can be guarded.
3570 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3571 vm_page_size()));
3572
3573 if (MaxFDLimit) {
3574 // set the number of file descriptors to max. print out error
3575 // if getrlimit/setrlimit fails but continue regardless.
3576 struct rlimit nbr_files;
3577 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3578 if (status != 0) {
3579 if (PrintMiscellaneous && (Verbose || WizardMode))
3580 perror("os::init_2 getrlimit failed");
3581 } else {
3582 nbr_files.rlim_cur = nbr_files.rlim_max;
3583
3584 #ifdef __APPLE__
3585 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3586 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3587 // be used instead
3588 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3589 #endif
3590
3591 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3592 if (status != 0) {
3593 if (PrintMiscellaneous && (Verbose || WizardMode))
3594 perror("os::init_2 setrlimit failed");
3595 }
3596 }
3597 }
3598
3599 // at-exit methods are called in the reverse order of their registration.
3600 // atexit functions are called on return from main or as a result of a
3601 // call to exit(3C). There can be only 32 of these functions registered
3602 // and atexit() does not set errno.
3603
3604 if (PerfAllowAtExitRegistration) {
3605 // only register atexit functions if PerfAllowAtExitRegistration is set.
3606 // atexit functions can be delayed until process exit time, which
3607 // can be problematic for embedded VM situations. Embedded VMs should
3608 // call DestroyJavaVM() to assure that VM resources are released.
3609
3610 // note: perfMemory_exit_helper atexit function may be removed in
3611 // the future if the appropriate cleanup code can be added to the
3612 // VM_Exit VMOperation's doit method.
3613 if (atexit(perfMemory_exit_helper) != 0) {
3614 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3615 }
3616 }
3617
3618 // initialize thread priority policy
3619 prio_init();
3620
3621 #ifdef __APPLE__
3622 // dynamically link to objective c gc registration
3623 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3624 if (handleLibObjc != NULL) {
3625 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3626 }
3627 #endif
3628
3629 return JNI_OK;
3630 }
3631
3632 // this is called at the end of vm_initialization
3633 void os::init_3(void) { }
3634
3635 // Mark the polling page as unreadable
3636 void os::make_polling_page_unreadable(void) {
3637 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3638 fatal("Could not disable polling page");
3639 };
3640
3641 // Mark the polling page as readable
3642 void os::make_polling_page_readable(void) {
3643 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3644 fatal("Could not enable polling page");
3645 }
3646 };
3647
3648 int os::active_processor_count() {
3649 return _processor_count;
3650 }
3651
3652 void os::set_native_thread_name(const char *name) {
3653 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3654 // This is only supported in Snow Leopard and beyond
3655 if (name != NULL) {
3656 // Add a "Java: " prefix to the name
3657 char buf[MAXTHREADNAMESIZE];
3658 snprintf(buf, sizeof(buf), "Java: %s", name);
3659 pthread_setname_np(buf);
3660 }
3661 #endif
3662 }
3663
3664 bool os::distribute_processes(uint length, uint* distribution) {
3665 // Not yet implemented.
3666 return false;
3667 }
3668
3669 bool os::bind_to_processor(uint processor_id) {
3670 // Not yet implemented.
3671 return false;
3672 }
3673
3674 void os::SuspendedThreadTask::internal_do_task() {
3675 if (do_suspend(_thread->osthread())) {
3676 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3677 do_task(context);
3678 do_resume(_thread->osthread());
3679 }
3680 }
3681
3682 ///
3683 class PcFetcher : public os::SuspendedThreadTask {
3684 public:
3685 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3686 ExtendedPC result();
3687 protected:
3688 void do_task(const os::SuspendedThreadTaskContext& context);
3689 private:
3690 ExtendedPC _epc;
3691 };
3692
3693 ExtendedPC PcFetcher::result() {
3694 guarantee(is_done(), "task is not done yet.");
3695 return _epc;
3696 }
3697
3698 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3699 Thread* thread = context.thread();
3700 OSThread* osthread = thread->osthread();
3701 if (osthread->ucontext() != NULL) {
3702 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3703 } else {
3704 // NULL context is unexpected, double-check this is the VMThread
3705 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3706 }
3707 }
3708
3709 // Suspends the target using the signal mechanism and then grabs the PC before
3710 // resuming the target. Used by the flat-profiler only
3711 ExtendedPC os::get_thread_pc(Thread* thread) {
3712 // Make sure that it is called by the watcher for the VMThread
3713 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3714 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3715
3716 PcFetcher fetcher(thread);
3717 fetcher.run();
3718 return fetcher.result();
3719 }
3720
3721 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3722 {
3723 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3724 }
3725
3726 ////////////////////////////////////////////////////////////////////////////////
3727 // debug support
3728
3729 bool os::find(address addr, outputStream* st) {
3730 Dl_info dlinfo;
3731 memset(&dlinfo, 0, sizeof(dlinfo));
3732 if (dladdr(addr, &dlinfo) != 0) {
3733 st->print(PTR_FORMAT ": ", addr);
3734 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3735 st->print("%s+%#x", dlinfo.dli_sname,
3736 addr - (intptr_t)dlinfo.dli_saddr);
3737 } else if (dlinfo.dli_fbase != NULL) {
3738 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3739 } else {
3740 st->print("<absolute address>");
3741 }
3742 if (dlinfo.dli_fname != NULL) {
3743 st->print(" in %s", dlinfo.dli_fname);
3744 }
3745 if (dlinfo.dli_fbase != NULL) {
3746 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3747 }
3748 st->cr();
3749
3750 if (Verbose) {
3751 // decode some bytes around the PC
3752 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3753 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3754 address lowest = (address) dlinfo.dli_sname;
3755 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3756 if (begin < lowest) begin = lowest;
3757 Dl_info dlinfo2;
3758 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3759 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3760 end = (address) dlinfo2.dli_saddr;
3761 Disassembler::decode(begin, end, st);
3762 }
3763 return true;
3764 }
3765 return false;
3766 }
3767
3768 ////////////////////////////////////////////////////////////////////////////////
3769 // misc
3770
3771 // This does not do anything on Bsd. This is basically a hook for being
3772 // able to use structured exception handling (thread-local exception filters)
3773 // on, e.g., Win32.
3774 void
3775 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3776 JavaCallArguments* args, Thread* thread) {
3777 f(value, method, args, thread);
3778 }
3779
3780 void os::print_statistics() {
3781 }
3782
3783 int os::message_box(const char* title, const char* message) {
3784 int i;
3785 fdStream err(defaultStream::error_fd());
3786 for (i = 0; i < 78; i++) err.print_raw("=");
3787 err.cr();
3788 err.print_raw_cr(title);
3789 for (i = 0; i < 78; i++) err.print_raw("-");
3790 err.cr();
3791 err.print_raw_cr(message);
3792 for (i = 0; i < 78; i++) err.print_raw("=");
3793 err.cr();
3794
3795 char buf[16];
3796 // Prevent process from exiting upon "read error" without consuming all CPU
3797 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3798
3799 return buf[0] == 'y' || buf[0] == 'Y';
3800 }
3801
3802 int os::stat(const char *path, struct stat *sbuf) {
3803 char pathbuf[MAX_PATH];
3804 if (strlen(path) > MAX_PATH - 1) {
3805 errno = ENAMETOOLONG;
3806 return -1;
3807 }
3808 os::native_path(strcpy(pathbuf, path));
3809 return ::stat(pathbuf, sbuf);
3810 }
3811
3812 bool os::check_heap(bool force) {
3813 return true;
3814 }
3815
3816 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3817 return ::vsnprintf(buf, count, format, args);
3818 }
3819
3820 // Is a (classpath) directory empty?
3821 bool os::dir_is_empty(const char* path) {
3822 DIR *dir = NULL;
3823 struct dirent *ptr;
3824
3825 dir = opendir(path);
3826 if (dir == NULL) return true;
3827
3828 /* Scan the directory */
3829 bool result = true;
3830 char buf[sizeof(struct dirent) + MAX_PATH];
3831 while (result && (ptr = ::readdir(dir)) != NULL) {
3832 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3833 result = false;
3834 }
3835 }
3836 closedir(dir);
3837 return result;
3838 }
3839
3840 // This code originates from JDK's sysOpen and open64_w
3841 // from src/solaris/hpi/src/system_md.c
3842
3843 #ifndef O_DELETE
3844 #define O_DELETE 0x10000
3845 #endif
3846
3847 // Open a file. Unlink the file immediately after open returns
3848 // if the specified oflag has the O_DELETE flag set.
3849 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3850
3851 int os::open(const char *path, int oflag, int mode) {
3852
3853 if (strlen(path) > MAX_PATH - 1) {
3854 errno = ENAMETOOLONG;
3855 return -1;
3856 }
3857 int fd;
3858 int o_delete = (oflag & O_DELETE);
3859 oflag = oflag & ~O_DELETE;
3860
3861 fd = ::open(path, oflag, mode);
3862 if (fd == -1) return -1;
3863
3864 //If the open succeeded, the file might still be a directory
3865 {
3866 struct stat buf;
3867 int ret = ::fstat(fd, &buf);
3868 int st_mode = buf.st_mode;
3869
3870 if (ret != -1) {
3871 if ((st_mode & S_IFMT) == S_IFDIR) {
3872 errno = EISDIR;
3873 ::close(fd);
3874 return -1;
3875 }
3876 } else {
3877 ::close(fd);
3878 return -1;
3879 }
3880 }
3881
3882 /*
3883 * All file descriptors that are opened in the JVM and not
3884 * specifically destined for a subprocess should have the
3885 * close-on-exec flag set. If we don't set it, then careless 3rd
3886 * party native code might fork and exec without closing all
3887 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3888 * UNIXProcess.c), and this in turn might:
3889 *
3890 * - cause end-of-file to fail to be detected on some file
3891 * descriptors, resulting in mysterious hangs, or
3892 *
3893 * - might cause an fopen in the subprocess to fail on a system
3894 * suffering from bug 1085341.
3895 *
3896 * (Yes, the default setting of the close-on-exec flag is a Unix
3897 * design flaw)
3898 *
3899 * See:
3900 * 1085341: 32-bit stdio routines should support file descriptors >255
3901 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3902 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3903 */
3904 #ifdef FD_CLOEXEC
3905 {
3906 int flags = ::fcntl(fd, F_GETFD);
3907 if (flags != -1)
3908 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3909 }
3910 #endif
3911
3912 if (o_delete != 0) {
3913 ::unlink(path);
3914 }
3915 return fd;
3916 }
3917
3918
3919 // create binary file, rewriting existing file if required
3920 int os::create_binary_file(const char* path, bool rewrite_existing) {
3921 int oflags = O_WRONLY | O_CREAT;
3922 if (!rewrite_existing) {
3923 oflags |= O_EXCL;
3924 }
3925 return ::open(path, oflags, S_IREAD | S_IWRITE);
3926 }
3927
3928 // return current position of file pointer
3929 jlong os::current_file_offset(int fd) {
3930 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3931 }
3932
3933 // move file pointer to the specified offset
3934 jlong os::seek_to_file_offset(int fd, jlong offset) {
3935 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3936 }
3937
3938 // This code originates from JDK's sysAvailable
3939 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3940
3941 int os::available(int fd, jlong *bytes) {
3942 jlong cur, end;
3943 int mode;
3944 struct stat buf;
3945
3946 if (::fstat(fd, &buf) >= 0) {
3947 mode = buf.st_mode;
3948 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3949 /*
3950 * XXX: is the following call interruptible? If so, this might
3951 * need to go through the INTERRUPT_IO() wrapper as for other
3952 * blocking, interruptible calls in this file.
3953 */
3954 int n;
3955 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3956 *bytes = n;
3957 return 1;
3958 }
3959 }
3960 }
3961 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3962 return 0;
3963 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3964 return 0;
3965 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3966 return 0;
3967 }
3968 *bytes = end - cur;
3969 return 1;
3970 }
3971
3972 int os::socket_available(int fd, jint *pbytes) {
3973 if (fd < 0)
3974 return OS_OK;
3975
3976 int ret;
3977
3978 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3979
3980 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3981 // is expected to return 0 on failure and 1 on success to the jdk.
3982
3983 return (ret == OS_ERR) ? 0 : 1;
3984 }
3985
3986 // Map a block of memory.
3987 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3988 char *addr, size_t bytes, bool read_only,
3989 bool allow_exec) {
3990 int prot;
3991 int flags;
3992
3993 if (read_only) {
3994 prot = PROT_READ;
3995 flags = MAP_SHARED;
3996 } else {
3997 prot = PROT_READ | PROT_WRITE;
3998 flags = MAP_PRIVATE;
3999 }
4000
4001 if (allow_exec) {
4002 prot |= PROT_EXEC;
4003 }
4004
4005 if (addr != NULL) {
4006 flags |= MAP_FIXED;
4007 }
4008
4009 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4010 fd, file_offset);
4011 if (mapped_address == MAP_FAILED) {
4012 return NULL;
4013 }
4014 return mapped_address;
4015 }
4016
4017
4018 // Remap a block of memory.
4019 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4020 char *addr, size_t bytes, bool read_only,
4021 bool allow_exec) {
4022 // same as map_memory() on this OS
4023 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4024 allow_exec);
4025 }
4026
4027
4028 // Unmap a block of memory.
4029 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4030 return munmap(addr, bytes) == 0;
4031 }
4032
4033 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4034 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4035 // of a thread.
4036 //
4037 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4038 // the fast estimate available on the platform.
4039
4040 jlong os::current_thread_cpu_time() {
4041 #ifdef __APPLE__
4042 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4043 #else
4044 Unimplemented();
4045 return 0;
4046 #endif
4047 }
4048
4049 jlong os::thread_cpu_time(Thread* thread) {
4050 #ifdef __APPLE__
4051 return os::thread_cpu_time(thread, true /* user + sys */);
4052 #else
4053 Unimplemented();
4054 return 0;
4055 #endif
4056 }
4057
4058 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4059 #ifdef __APPLE__
4060 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4061 #else
4062 Unimplemented();
4063 return 0;
4064 #endif
4065 }
4066
4067 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4068 #ifdef __APPLE__
4069 struct thread_basic_info tinfo;
4070 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4071 kern_return_t kr;
4072 thread_t mach_thread;
4073
4074 mach_thread = thread->osthread()->thread_id();
4075 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4076 if (kr != KERN_SUCCESS)
4077 return -1;
4078
4079 if (user_sys_cpu_time) {
4080 jlong nanos;
4081 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4082 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4083 return nanos;
4084 } else {
4085 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4086 }
4087 #else
4088 Unimplemented();
4089 return 0;
4090 #endif
4091 }
4092
4093
4094 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4095 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4096 info_ptr->may_skip_backward = false; // elapsed time not wall time
4097 info_ptr->may_skip_forward = false; // elapsed time not wall time
4098 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4099 }
4100
4101 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4102 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4103 info_ptr->may_skip_backward = false; // elapsed time not wall time
4104 info_ptr->may_skip_forward = false; // elapsed time not wall time
4105 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4106 }
4107
4108 bool os::is_thread_cpu_time_supported() {
4109 #ifdef __APPLE__
4110 return true;
4111 #else
4112 return false;
4113 #endif
4114 }
4115
4116 // System loadavg support. Returns -1 if load average cannot be obtained.
4117 // Bsd doesn't yet have a (official) notion of processor sets,
4118 // so just return the system wide load average.
4119 int os::loadavg(double loadavg[], int nelem) {
4120 return ::getloadavg(loadavg, nelem);
4121 }
4122
4123 void os::pause() {
4124 char filename[MAX_PATH];
4125 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4126 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4127 } else {
4128 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4129 }
4130
4131 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4132 if (fd != -1) {
4133 struct stat buf;
4134 ::close(fd);
4135 while (::stat(filename, &buf) == 0) {
4136 (void)::poll(NULL, 0, 100);
4137 }
4138 } else {
4139 jio_fprintf(stderr,
4140 "Could not open pause file '%s', continuing immediately.\n", filename);
4141 }
4142 }
4143
4144
4145 // Refer to the comments in os_solaris.cpp park-unpark.
4146 //
4147 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4148 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4149 // For specifics regarding the bug see GLIBC BUGID 261237 :
4150 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4151 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4152 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4153 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4154 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4155 // and monitorenter when we're using 1-0 locking. All those operations may result in
4156 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4157 // of libpthread avoids the problem, but isn't practical.
4158 //
4159 // Possible remedies:
4160 //
4161 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4162 // This is palliative and probabilistic, however. If the thread is preempted
4163 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4164 // than the minimum period may have passed, and the abstime may be stale (in the
4165 // past) resultin in a hang. Using this technique reduces the odds of a hang
4166 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4167 //
4168 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4169 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4170 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4171 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4172 // thread.
4173 //
4174 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4175 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4176 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4177 // This also works well. In fact it avoids kernel-level scalability impediments
4178 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4179 // timers in a graceful fashion.
4180 //
4181 // 4. When the abstime value is in the past it appears that control returns
4182 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4183 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4184 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4185 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4186 // It may be possible to avoid reinitialization by checking the return
4187 // value from pthread_cond_timedwait(). In addition to reinitializing the
4188 // condvar we must establish the invariant that cond_signal() is only called
4189 // within critical sections protected by the adjunct mutex. This prevents
4190 // cond_signal() from "seeing" a condvar that's in the midst of being
4191 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4192 // desirable signal-after-unlock optimization that avoids futile context switching.
4193 //
4194 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4195 // structure when a condvar is used or initialized. cond_destroy() would
4196 // release the helper structure. Our reinitialize-after-timedwait fix
4197 // put excessive stress on malloc/free and locks protecting the c-heap.
4198 //
4199 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4200 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4201 // and only enabling the work-around for vulnerable environments.
4202
4203 // utility to compute the abstime argument to timedwait:
4204 // millis is the relative timeout time
4205 // abstime will be the absolute timeout time
4206 // TODO: replace compute_abstime() with unpackTime()
4207
4208 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4209 if (millis < 0) millis = 0;
4210 struct timeval now;
4211 int status = gettimeofday(&now, NULL);
4212 assert(status == 0, "gettimeofday");
4213 jlong seconds = millis / 1000;
4214 millis %= 1000;
4215 if (seconds > 50000000) { // see man cond_timedwait(3T)
4216 seconds = 50000000;
4217 }
4218 abstime->tv_sec = now.tv_sec + seconds;
4219 long usec = now.tv_usec + millis * 1000;
4220 if (usec >= 1000000) {
4221 abstime->tv_sec += 1;
4222 usec -= 1000000;
4223 }
4224 abstime->tv_nsec = usec * 1000;
4225 return abstime;
4226 }
4227
4228
4229 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4230 // Conceptually TryPark() should be equivalent to park(0).
4231
4232 int os::PlatformEvent::TryPark() {
4233 for (;;) {
4234 const int v = _Event ;
4235 guarantee ((v == 0) || (v == 1), "invariant") ;
4236 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4237 }
4238 }
4239
4240 void os::PlatformEvent::park() { // AKA "down()"
4241 // Invariant: Only the thread associated with the Event/PlatformEvent
4242 // may call park().
4243 // TODO: assert that _Assoc != NULL or _Assoc == Self
4244 int v ;
4245 for (;;) {
4246 v = _Event ;
4247 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4248 }
4249 guarantee (v >= 0, "invariant") ;
4250 if (v == 0) {
4251 // Do this the hard way by blocking ...
4252 int status = pthread_mutex_lock(_mutex);
4253 assert_status(status == 0, status, "mutex_lock");
4254 guarantee (_nParked == 0, "invariant") ;
4255 ++ _nParked ;
4256 while (_Event < 0) {
4257 status = pthread_cond_wait(_cond, _mutex);
4258 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4259 // Treat this the same as if the wait was interrupted
4260 if (status == ETIMEDOUT) { status = EINTR; }
4261 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4262 }
4263 -- _nParked ;
4264
4265 _Event = 0 ;
4266 status = pthread_mutex_unlock(_mutex);
4267 assert_status(status == 0, status, "mutex_unlock");
4268 // Paranoia to ensure our locked and lock-free paths interact
4269 // correctly with each other.
4270 OrderAccess::fence();
4271 }
4272 guarantee (_Event >= 0, "invariant") ;
4273 }
4274
4275 int os::PlatformEvent::park(jlong millis) {
4276 guarantee (_nParked == 0, "invariant") ;
4277
4278 int v ;
4279 for (;;) {
4280 v = _Event ;
4281 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4282 }
4283 guarantee (v >= 0, "invariant") ;
4284 if (v != 0) return OS_OK ;
4285
4286 // We do this the hard way, by blocking the thread.
4287 // Consider enforcing a minimum timeout value.
4288 struct timespec abst;
4289 compute_abstime(&abst, millis);
4290
4291 int ret = OS_TIMEOUT;
4292 int status = pthread_mutex_lock(_mutex);
4293 assert_status(status == 0, status, "mutex_lock");
4294 guarantee (_nParked == 0, "invariant") ;
4295 ++_nParked ;
4296
4297 // Object.wait(timo) will return because of
4298 // (a) notification
4299 // (b) timeout
4300 // (c) thread.interrupt
4301 //
4302 // Thread.interrupt and object.notify{All} both call Event::set.
4303 // That is, we treat thread.interrupt as a special case of notification.
4304 // The underlying Solaris implementation, cond_timedwait, admits
4305 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4306 // JVM from making those visible to Java code. As such, we must
4307 // filter out spurious wakeups. We assume all ETIME returns are valid.
4308 //
4309 // TODO: properly differentiate simultaneous notify+interrupt.
4310 // In that case, we should propagate the notify to another waiter.
4311
4312 while (_Event < 0) {
4313 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4314 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4315 pthread_cond_destroy (_cond);
4316 pthread_cond_init (_cond, NULL) ;
4317 }
4318 assert_status(status == 0 || status == EINTR ||
4319 status == ETIMEDOUT,
4320 status, "cond_timedwait");
4321 if (!FilterSpuriousWakeups) break ; // previous semantics
4322 if (status == ETIMEDOUT) break ;
4323 // We consume and ignore EINTR and spurious wakeups.
4324 }
4325 --_nParked ;
4326 if (_Event >= 0) {
4327 ret = OS_OK;
4328 }
4329 _Event = 0 ;
4330 status = pthread_mutex_unlock(_mutex);
4331 assert_status(status == 0, status, "mutex_unlock");
4332 assert (_nParked == 0, "invariant") ;
4333 // Paranoia to ensure our locked and lock-free paths interact
4334 // correctly with each other.
4335 OrderAccess::fence();
4336 return ret;
4337 }
4338
4339 void os::PlatformEvent::unpark() {
4340 // Transitions for _Event:
4341 // 0 :=> 1
4342 // 1 :=> 1
4343 // -1 :=> either 0 or 1; must signal target thread
4344 // That is, we can safely transition _Event from -1 to either
4345 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4346 // unpark() calls.
4347 // See also: "Semaphores in Plan 9" by Mullender & Cox
4348 //
4349 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4350 // that it will take two back-to-back park() calls for the owning
4351 // thread to block. This has the benefit of forcing a spurious return
4352 // from the first park() call after an unpark() call which will help
4353 // shake out uses of park() and unpark() without condition variables.
4354
4355 if (Atomic::xchg(1, &_Event) >= 0) return;
4356
4357 // Wait for the thread associated with the event to vacate
4358 int status = pthread_mutex_lock(_mutex);
4359 assert_status(status == 0, status, "mutex_lock");
4360 int AnyWaiters = _nParked;
4361 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4362 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4363 AnyWaiters = 0;
4364 pthread_cond_signal(_cond);
4365 }
4366 status = pthread_mutex_unlock(_mutex);
4367 assert_status(status == 0, status, "mutex_unlock");
4368 if (AnyWaiters != 0) {
4369 status = pthread_cond_signal(_cond);
4370 assert_status(status == 0, status, "cond_signal");
4371 }
4372
4373 // Note that we signal() _after dropping the lock for "immortal" Events.
4374 // This is safe and avoids a common class of futile wakeups. In rare
4375 // circumstances this can cause a thread to return prematurely from
4376 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4377 // simply re-test the condition and re-park itself.
4378 }
4379
4380
4381 // JSR166
4382 // -------------------------------------------------------
4383
4384 /*
4385 * The solaris and bsd implementations of park/unpark are fairly
4386 * conservative for now, but can be improved. They currently use a
4387 * mutex/condvar pair, plus a a count.
4388 * Park decrements count if > 0, else does a condvar wait. Unpark
4389 * sets count to 1 and signals condvar. Only one thread ever waits
4390 * on the condvar. Contention seen when trying to park implies that someone
4391 * is unparking you, so don't wait. And spurious returns are fine, so there
4392 * is no need to track notifications.
4393 */
4394
4395 #define MAX_SECS 100000000
4396 /*
4397 * This code is common to bsd and solaris and will be moved to a
4398 * common place in dolphin.
4399 *
4400 * The passed in time value is either a relative time in nanoseconds
4401 * or an absolute time in milliseconds. Either way it has to be unpacked
4402 * into suitable seconds and nanoseconds components and stored in the
4403 * given timespec structure.
4404 * Given time is a 64-bit value and the time_t used in the timespec is only
4405 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4406 * overflow if times way in the future are given. Further on Solaris versions
4407 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4408 * number of seconds, in abstime, is less than current_time + 100,000,000.
4409 * As it will be 28 years before "now + 100000000" will overflow we can
4410 * ignore overflow and just impose a hard-limit on seconds using the value
4411 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4412 * years from "now".
4413 */
4414
4415 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4416 assert (time > 0, "convertTime");
4417
4418 struct timeval now;
4419 int status = gettimeofday(&now, NULL);
4420 assert(status == 0, "gettimeofday");
4421
4422 time_t max_secs = now.tv_sec + MAX_SECS;
4423
4424 if (isAbsolute) {
4425 jlong secs = time / 1000;
4426 if (secs > max_secs) {
4427 absTime->tv_sec = max_secs;
4428 }
4429 else {
4430 absTime->tv_sec = secs;
4431 }
4432 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4433 }
4434 else {
4435 jlong secs = time / NANOSECS_PER_SEC;
4436 if (secs >= MAX_SECS) {
4437 absTime->tv_sec = max_secs;
4438 absTime->tv_nsec = 0;
4439 }
4440 else {
4441 absTime->tv_sec = now.tv_sec + secs;
4442 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4443 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4444 absTime->tv_nsec -= NANOSECS_PER_SEC;
4445 ++absTime->tv_sec; // note: this must be <= max_secs
4446 }
4447 }
4448 }
4449 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4450 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4451 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4452 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4453 }
4454
4455 void Parker::park(bool isAbsolute, jlong time) {
4456 // Ideally we'd do something useful while spinning, such
4457 // as calling unpackTime().
4458
4459 // Optional fast-path check:
4460 // Return immediately if a permit is available.
4461 // We depend on Atomic::xchg() having full barrier semantics
4462 // since we are doing a lock-free update to _counter.
4463 if (Atomic::xchg(0, &_counter) > 0) return;
4464
4465 Thread* thread = Thread::current();
4466 assert(thread->is_Java_thread(), "Must be JavaThread");
4467 JavaThread *jt = (JavaThread *)thread;
4468
4469 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4470 // Check interrupt before trying to wait
4471 if (Thread::is_interrupted(thread, false)) {
4472 return;
4473 }
4474
4475 // Next, demultiplex/decode time arguments
4476 struct timespec absTime;
4477 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4478 return;
4479 }
4480 if (time > 0) {
4481 unpackTime(&absTime, isAbsolute, time);
4482 }
4483
4484
4485 // Enter safepoint region
4486 // Beware of deadlocks such as 6317397.
4487 // The per-thread Parker:: mutex is a classic leaf-lock.
4488 // In particular a thread must never block on the Threads_lock while
4489 // holding the Parker:: mutex. If safepoints are pending both the
4490 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4491 ThreadBlockInVM tbivm(jt);
4492
4493 // Don't wait if cannot get lock since interference arises from
4494 // unblocking. Also. check interrupt before trying wait
4495 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4496 return;
4497 }
4498
4499 int status ;
4500 if (_counter > 0) { // no wait needed
4501 _counter = 0;
4502 status = pthread_mutex_unlock(_mutex);
4503 assert (status == 0, "invariant") ;
4504 // Paranoia to ensure our locked and lock-free paths interact
4505 // correctly with each other and Java-level accesses.
4506 OrderAccess::fence();
4507 return;
4508 }
4509
4510 #ifdef ASSERT
4511 // Don't catch signals while blocked; let the running threads have the signals.
4512 // (This allows a debugger to break into the running thread.)
4513 sigset_t oldsigs;
4514 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4515 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4516 #endif
4517
4518 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4519 jt->set_suspend_equivalent();
4520 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4521
4522 if (time == 0) {
4523 status = pthread_cond_wait (_cond, _mutex) ;
4524 } else {
4525 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4526 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4527 pthread_cond_destroy (_cond) ;
4528 pthread_cond_init (_cond, NULL);
4529 }
4530 }
4531 assert_status(status == 0 || status == EINTR ||
4532 status == ETIMEDOUT,
4533 status, "cond_timedwait");
4534
4535 #ifdef ASSERT
4536 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4537 #endif
4538
4539 _counter = 0 ;
4540 status = pthread_mutex_unlock(_mutex) ;
4541 assert_status(status == 0, status, "invariant") ;
4542 // Paranoia to ensure our locked and lock-free paths interact
4543 // correctly with each other and Java-level accesses.
4544 OrderAccess::fence();
4545
4546 // If externally suspended while waiting, re-suspend
4547 if (jt->handle_special_suspend_equivalent_condition()) {
4548 jt->java_suspend_self();
4549 }
4550 }
4551
4552 void Parker::unpark() {
4553 int s, status ;
4554 status = pthread_mutex_lock(_mutex);
4555 assert (status == 0, "invariant") ;
4556 s = _counter;
4557 _counter = 1;
4558 if (s < 1) {
4559 if (WorkAroundNPTLTimedWaitHang) {
4560 status = pthread_cond_signal (_cond) ;
4561 assert (status == 0, "invariant") ;
4562 status = pthread_mutex_unlock(_mutex);
4563 assert (status == 0, "invariant") ;
4564 } else {
4565 status = pthread_mutex_unlock(_mutex);
4566 assert (status == 0, "invariant") ;
4567 status = pthread_cond_signal (_cond) ;
4568 assert (status == 0, "invariant") ;
4569 }
4570 } else {
4571 pthread_mutex_unlock(_mutex);
4572 assert (status == 0, "invariant") ;
4573 }
4574 }
4575
4576
4577 /* Darwin has no "environ" in a dynamic library. */
4578 #ifdef __APPLE__
4579 #include <crt_externs.h>
4580 #define environ (*_NSGetEnviron())
4581 #else
4582 extern char** environ;
4583 #endif
4584
4585 // Run the specified command in a separate process. Return its exit value,
4586 // or -1 on failure (e.g. can't fork a new process).
4587 // Unlike system(), this function can be called from signal handler. It
4588 // doesn't block SIGINT et al.
4589 int os::fork_and_exec(char* cmd) {
4590 const char * argv[4] = {"sh", "-c", cmd, NULL};
4591
4592 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4593 // pthread_atfork handlers and reset pthread library. All we need is a
4594 // separate process to execve. Make a direct syscall to fork process.
4595 // On IA64 there's no fork syscall, we have to use fork() and hope for
4596 // the best...
4597 pid_t pid = fork();
4598
4599 if (pid < 0) {
4600 // fork failed
4601 return -1;
4602
4603 } else if (pid == 0) {
4604 // child process
4605
4606 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4607 // first to kill every thread on the thread list. Because this list is
4608 // not reset by fork() (see notes above), execve() will instead kill
4609 // every thread in the parent process. We know this is the only thread
4610 // in the new process, so make a system call directly.
4611 // IA64 should use normal execve() from glibc to match the glibc fork()
4612 // above.
4613 execve("/bin/sh", (char* const*)argv, environ);
4614
4615 // execve failed
4616 _exit(-1);
4617
4618 } else {
4619 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4620 // care about the actual exit code, for now.
4621
4622 int status;
4623
4624 // Wait for the child process to exit. This returns immediately if
4625 // the child has already exited. */
4626 while (waitpid(pid, &status, 0) < 0) {
4627 switch (errno) {
4628 case ECHILD: return 0;
4629 case EINTR: break;
4630 default: return -1;
4631 }
4632 }
4633
4634 if (WIFEXITED(status)) {
4635 // The child exited normally; get its exit code.
4636 return WEXITSTATUS(status);
4637 } else if (WIFSIGNALED(status)) {
4638 // The child exited because of a signal
4639 // The best value to return is 0x80 + signal number,
4640 // because that is what all Unix shells do, and because
4641 // it allows callers to distinguish between process exit and
4642 // process death by signal.
4643 return 0x80 + WTERMSIG(status);
4644 } else {
4645 // Unknown exit code; pass it through
4646 return status;
4647 }
4648 }
4649 }
4650
4651 // is_headless_jre()
4652 //
4653 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4654 // in order to report if we are running in a headless jre
4655 //
4656 // Since JDK8 xawt/libmawt.so was moved into the same directory
4657 // as libawt.so, and renamed libawt_xawt.so
4658 //
4659 bool os::is_headless_jre() {
4660 #ifdef __APPLE__
4661 // We no longer build headless-only on Mac OS X
4662 return false;
4663 #else
4664 struct stat statbuf;
4665 char buf[MAXPATHLEN];
4666 char libmawtpath[MAXPATHLEN];
4667 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4668 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4669 char *p;
4670
4671 // Get path to libjvm.so
4672 os::jvm_path(buf, sizeof(buf));
4673
4674 // Get rid of libjvm.so
4675 p = strrchr(buf, '/');
4676 if (p == NULL) return false;
4677 else *p = '\0';
4678
4679 // Get rid of client or server
4680 p = strrchr(buf, '/');
4681 if (p == NULL) return false;
4682 else *p = '\0';
4683
4684 // check xawt/libmawt.so
4685 strcpy(libmawtpath, buf);
4686 strcat(libmawtpath, xawtstr);
4687 if (::stat(libmawtpath, &statbuf) == 0) return false;
4688
4689 // check libawt_xawt.so
4690 strcpy(libmawtpath, buf);
4691 strcat(libmawtpath, new_xawtstr);
4692 if (::stat(libmawtpath, &statbuf) == 0) return false;
4693
4694 return true;
4695 #endif
4696 }
4697
4698 // Get the default path to the core file
4699 // Returns the length of the string
4700 int os::get_core_path(char* buffer, size_t bufferSize) {
4701 int n = jio_snprintf(buffer, bufferSize, "/cores");
4702
4703 // Truncate if theoretical string was longer than bufferSize
4704 n = MIN2(n, (int)bufferSize);
4705
4706 return n;
4707 }
4708
4709 #ifndef PRODUCT
4710 void TestReserveMemorySpecial_test() {
4711 // No tests available for this platform
4712 }
4713 #endif