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/orderAccess.inline.hpp"
52 #include "runtime/osThread.hpp"
53 #include "runtime/perfMemory.hpp"
54 #include "runtime/sharedRuntime.hpp"
55 #include "runtime/statSampler.hpp"
56 #include "runtime/stubRoutines.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "runtime/threadCritical.hpp"
59 #include "runtime/timer.hpp"
60 #include "services/attachListener.hpp"
61 #include "services/memTracker.hpp"
62 #include "services/runtimeService.hpp"
63 #include "utilities/decoder.hpp"
64 #include "utilities/defaultStream.hpp"
65 #include "utilities/events.hpp"
66 #include "utilities/growableArray.hpp"
67 #include "utilities/vmError.hpp"
68
69 // put OS-includes here
70 # include <sys/types.h>
71 # include <sys/mman.h>
72 # include <sys/stat.h>
73 # include <sys/select.h>
74 # include <pthread.h>
75 # include <signal.h>
76 # include <errno.h>
77 # include <dlfcn.h>
78 # include <stdio.h>
79 # include <unistd.h>
80 # include <sys/resource.h>
81 # include <pthread.h>
82 # include <sys/stat.h>
83 # include <sys/time.h>
84 # include <sys/times.h>
85 # include <sys/utsname.h>
86 # include <sys/socket.h>
87 # include <sys/wait.h>
88 # include <time.h>
89 # include <pwd.h>
90 # include <poll.h>
91 # include <semaphore.h>
92 # include <fcntl.h>
93 # include <string.h>
94 # include <sys/param.h>
95 # include <sys/sysctl.h>
96 # include <sys/ipc.h>
97 # include <sys/shm.h>
98 #ifndef __APPLE__
99 # include <link.h>
100 #endif
101 # include <stdint.h>
102 # include <inttypes.h>
103 # include <sys/ioctl.h>
104 # include <sys/syscall.h>
105
106 #if defined(__FreeBSD__) || defined(__NetBSD__)
107 # include <elf.h>
108 #endif
109
110 #ifdef __APPLE__
111 # include <mach/mach.h> // semaphore_* API
112 # include <mach-o/dyld.h>
113 # include <sys/proc_info.h>
114 # include <objc/objc-auto.h>
115 #endif
116
117 #ifndef MAP_ANONYMOUS
118 #define MAP_ANONYMOUS MAP_ANON
119 #endif
120
121 #define MAX_PATH (2 * K)
122
123 // for timer info max values which include all bits
124 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
125
126 #define LARGEPAGES_BIT (1 << 6)
127
128 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
129
130 ////////////////////////////////////////////////////////////////////////////////
131 // global variables
132 julong os::Bsd::_physical_memory = 0;
133
134 #ifdef __APPLE__
135 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
136 volatile uint64_t os::Bsd::_max_abstime = 0;
137 #else
138 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
139 #endif
140 pthread_t os::Bsd::_main_thread;
141 int os::Bsd::_page_size = -1;
142
143 static jlong initial_time_count=0;
144
145 static int clock_tics_per_sec = 100;
146
147 // For diagnostics to print a message once. see run_periodic_checks
148 static sigset_t check_signal_done;
149 static bool check_signals = true;
150
151 static pid_t _initial_pid = 0;
152
153 /* Signal number used to suspend/resume a thread */
154
155 /* do not use any signal number less than SIGSEGV, see 4355769 */
156 static int SR_signum = SIGUSR2;
157 sigset_t SR_sigset;
158
159
160 ////////////////////////////////////////////////////////////////////////////////
161 // utility functions
162
163 static int SR_initialize();
164 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
165
166 julong os::available_memory() {
167 return Bsd::available_memory();
168 }
169
170 // available here means free
171 julong os::Bsd::available_memory() {
172 uint64_t available = physical_memory() >> 2;
173 #ifdef __APPLE__
174 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
175 vm_statistics64_data_t vmstat;
176 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
177 (host_info64_t)&vmstat, &count);
178 assert(kerr == KERN_SUCCESS,
179 "host_statistics64 failed - check mach_host_self() and count");
180 if (kerr == KERN_SUCCESS) {
181 available = vmstat.free_count * os::vm_page_size();
182 }
183 #endif
184 return available;
185 }
186
187 julong os::physical_memory() {
188 return Bsd::physical_memory();
189 }
190
191 ////////////////////////////////////////////////////////////////////////////////
192 // environment support
193
194 bool os::getenv(const char* name, char* buf, int len) {
195 const char* val = ::getenv(name);
196 if (val != NULL && strlen(val) < (size_t)len) {
197 strcpy(buf, val);
198 return true;
199 }
200 if (len > 0) buf[0] = 0; // return a null string
201 return false;
202 }
203
204
205 // Return true if user is running as root.
206
207 bool os::have_special_privileges() {
208 static bool init = false;
209 static bool privileges = false;
210 if (!init) {
211 privileges = (getuid() != geteuid()) || (getgid() != getegid());
212 init = true;
213 }
214 return privileges;
215 }
216
217
218
219 // Cpu architecture string
220 #if defined(ZERO)
221 static char cpu_arch[] = ZERO_LIBARCH;
222 #elif defined(IA64)
223 static char cpu_arch[] = "ia64";
224 #elif defined(IA32)
225 static char cpu_arch[] = "i386";
226 #elif defined(AMD64)
227 static char cpu_arch[] = "amd64";
228 #elif defined(ARM)
229 static char cpu_arch[] = "arm";
230 #elif defined(PPC32)
231 static char cpu_arch[] = "ppc";
232 #elif defined(SPARC)
233 # ifdef _LP64
234 static char cpu_arch[] = "sparcv9";
235 # else
236 static char cpu_arch[] = "sparc";
237 # endif
238 #else
239 #error Add appropriate cpu_arch setting
240 #endif
241
242 // Compiler variant
243 #ifdef COMPILER2
244 #define COMPILER_VARIANT "server"
245 #else
246 #define COMPILER_VARIANT "client"
247 #endif
248
249
250 void os::Bsd::initialize_system_info() {
251 int mib[2];
252 size_t len;
253 int cpu_val;
254 julong mem_val;
255
256 /* get processors count via hw.ncpus sysctl */
257 mib[0] = CTL_HW;
258 mib[1] = HW_NCPU;
259 len = sizeof(cpu_val);
260 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
261 assert(len == sizeof(cpu_val), "unexpected data size");
262 set_processor_count(cpu_val);
263 }
264 else {
265 set_processor_count(1); // fallback
266 }
267
268 /* get physical memory via hw.memsize sysctl (hw.memsize is used
269 * since it returns a 64 bit value)
270 */
271 mib[0] = CTL_HW;
272
273 #if defined (HW_MEMSIZE) // Apple
274 mib[1] = HW_MEMSIZE;
275 #elif defined(HW_PHYSMEM) // Most of BSD
276 mib[1] = HW_PHYSMEM;
277 #elif defined(HW_REALMEM) // Old FreeBSD
278 mib[1] = HW_REALMEM;
279 #else
280 #error No ways to get physmem
281 #endif
282
283 len = sizeof(mem_val);
284 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
285 assert(len == sizeof(mem_val), "unexpected data size");
286 _physical_memory = mem_val;
287 } else {
288 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
289 }
290
291 #ifdef __OpenBSD__
292 {
293 // limit _physical_memory memory view on OpenBSD since
294 // datasize rlimit restricts us anyway.
295 struct rlimit limits;
296 getrlimit(RLIMIT_DATA, &limits);
297 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
298 }
299 #endif
300 }
301
302 #ifdef __APPLE__
303 static const char *get_home() {
304 const char *home_dir = ::getenv("HOME");
305 if ((home_dir == NULL) || (*home_dir == '\0')) {
306 struct passwd *passwd_info = getpwuid(geteuid());
307 if (passwd_info != NULL) {
308 home_dir = passwd_info->pw_dir;
309 }
310 }
311
312 return home_dir;
313 }
314 #endif
315
316 void os::init_system_properties_values() {
317 // The next steps are taken in the product version:
318 //
319 // Obtain the JAVA_HOME value from the location of libjvm.so.
320 // This library should be located at:
321 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
322 //
323 // If "/jre/lib/" appears at the right place in the path, then we
324 // assume libjvm.so is installed in a JDK and we use this path.
325 //
326 // Otherwise exit with message: "Could not create the Java virtual machine."
327 //
328 // The following extra steps are taken in the debugging version:
329 //
330 // If "/jre/lib/" does NOT appear at the right place in the path
331 // instead of exit check for $JAVA_HOME environment variable.
332 //
333 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
334 // then we append a fake suffix "hotspot/libjvm.so" to this path so
335 // it looks like libjvm.so is installed there
336 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
337 //
338 // Otherwise exit.
339 //
340 // Important note: if the location of libjvm.so changes this
341 // code needs to be changed accordingly.
342
343 // See ld(1):
344 // The linker uses the following search paths to locate required
345 // shared libraries:
346 // 1: ...
347 // ...
348 // 7: The default directories, normally /lib and /usr/lib.
349 #ifndef DEFAULT_LIBPATH
350 #define DEFAULT_LIBPATH "/lib:/usr/lib"
351 #endif
352
353 // Base path of extensions installed on the system.
354 #define SYS_EXT_DIR "/usr/java/packages"
355 #define EXTENSIONS_DIR "/lib/ext"
356 #define ENDORSED_DIR "/lib/endorsed"
357
358 #ifndef __APPLE__
359
360 // Buffer that fits several sprintfs.
361 // Note that the space for the colon and the trailing null are provided
362 // by the nulls included by the sizeof operator.
363 const size_t bufsize =
364 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends.
365 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir
366 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
367 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
368
369 // sysclasspath, java_home, dll_dir
370 {
371 char *pslash;
372 os::jvm_path(buf, bufsize);
373
374 // Found the full path to libjvm.so.
375 // Now cut the path to <java_home>/jre if we can.
376 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
377 pslash = strrchr(buf, '/');
378 if (pslash != NULL) {
379 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
380 }
381 Arguments::set_dll_dir(buf);
382
383 if (pslash != NULL) {
384 pslash = strrchr(buf, '/');
385 if (pslash != NULL) {
386 *pslash = '\0'; // Get rid of /<arch>.
387 pslash = strrchr(buf, '/');
388 if (pslash != NULL) {
389 *pslash = '\0'; // Get rid of /lib.
390 }
391 }
392 }
393 Arguments::set_java_home(buf);
394 set_boot_path('/', ':');
395 }
396
397 // Where to look for native libraries.
398 //
399 // Note: Due to a legacy implementation, most of the library path
400 // is set in the launcher. This was to accomodate linking restrictions
401 // on legacy Bsd implementations (which are no longer supported).
402 // Eventually, all the library path setting will be done here.
403 //
404 // However, to prevent the proliferation of improperly built native
405 // libraries, the new path component /usr/java/packages is added here.
406 // Eventually, all the library path setting will be done here.
407 {
408 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
409 // should always exist (until the legacy problem cited above is
410 // addressed).
411 const char *v = ::getenv("LD_LIBRARY_PATH");
412 const char *v_colon = ":";
413 if (v == NULL) { v = ""; v_colon = ""; }
414 // That's +1 for the colon and +1 for the trailing '\0'.
415 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
416 strlen(v) + 1 +
417 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
418 mtInternal);
419 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
420 Arguments::set_library_path(ld_library_path);
421 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
422 }
423
424 // Extensions directories.
425 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
426 Arguments::set_ext_dirs(buf);
427
428 // Endorsed standards default directory.
429 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
430 Arguments::set_endorsed_dirs(buf);
431
432 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
433
434 #else // __APPLE__
435
436 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
437 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
438
439 const char *user_home_dir = get_home();
440 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
441 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
442 sizeof(SYS_EXTENSIONS_DIRS);
443
444 // Buffer that fits several sprintfs.
445 // Note that the space for the colon and the trailing null are provided
446 // by the nulls included by the sizeof operator.
447 const size_t bufsize =
448 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends.
449 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir
450 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
451 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
452
453 // sysclasspath, java_home, dll_dir
454 {
455 char *pslash;
456 os::jvm_path(buf, bufsize);
457
458 // Found the full path to libjvm.so.
459 // Now cut the path to <java_home>/jre if we can.
460 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
461 pslash = strrchr(buf, '/');
462 if (pslash != NULL) {
463 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
464 }
465 Arguments::set_dll_dir(buf);
466
467 if (pslash != NULL) {
468 pslash = strrchr(buf, '/');
469 if (pslash != NULL) {
470 *pslash = '\0'; // Get rid of /lib.
471 }
472 }
473 Arguments::set_java_home(buf);
474 set_boot_path('/', ':');
475 }
476
477 // Where to look for native libraries.
478 //
479 // Note: Due to a legacy implementation, most of the library path
480 // is set in the launcher. This was to accomodate linking restrictions
481 // on legacy Bsd implementations (which are no longer supported).
482 // Eventually, all the library path setting will be done here.
483 //
484 // However, to prevent the proliferation of improperly built native
485 // libraries, the new path component /usr/java/packages is added here.
486 // Eventually, all the library path setting will be done here.
487 {
488 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
489 // should always exist (until the legacy problem cited above is
490 // addressed).
491 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
492 // can specify a directory inside an app wrapper
493 const char *l = ::getenv("JAVA_LIBRARY_PATH");
494 const char *l_colon = ":";
495 if (l == NULL) { l = ""; l_colon = ""; }
496
497 const char *v = ::getenv("DYLD_LIBRARY_PATH");
498 const char *v_colon = ":";
499 if (v == NULL) { v = ""; v_colon = ""; }
500
501 // Apple's Java6 has "." at the beginning of java.library.path.
502 // OpenJDK on Windows has "." at the end of java.library.path.
503 // OpenJDK on Linux and Solaris don't have "." in java.library.path
504 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
505 // "." is appended to the end of java.library.path. Yes, this
506 // could cause a change in behavior, but Apple's Java6 behavior
507 // can be achieved by putting "." at the beginning of the
508 // JAVA_LIBRARY_PATH environment variable.
509 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
510 strlen(v) + 1 + strlen(l) + 1 +
511 system_ext_size + 3,
512 mtInternal);
513 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
514 v, v_colon, l, l_colon, user_home_dir);
515 Arguments::set_library_path(ld_library_path);
516 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
517 }
518
519 // Extensions directories.
520 //
521 // Note that the space for the colon and the trailing null are provided
522 // by the nulls included by the sizeof operator (so actually one byte more
523 // than necessary is allocated).
524 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
525 user_home_dir, Arguments::get_java_home());
526 Arguments::set_ext_dirs(buf);
527
528 // Endorsed standards default directory.
529 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
530 Arguments::set_endorsed_dirs(buf);
531
532 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
533
534 #undef SYS_EXTENSIONS_DIR
535 #undef SYS_EXTENSIONS_DIRS
536
537 #endif // __APPLE__
538
539 #undef SYS_EXT_DIR
540 #undef EXTENSIONS_DIR
541 #undef ENDORSED_DIR
542 }
543
544 ////////////////////////////////////////////////////////////////////////////////
545 // breakpoint support
546
547 void os::breakpoint() {
548 BREAKPOINT;
549 }
550
551 extern "C" void breakpoint() {
552 // use debugger to set breakpoint here
553 }
554
555 ////////////////////////////////////////////////////////////////////////////////
556 // signal support
557
558 debug_only(static bool signal_sets_initialized = false);
559 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
560
561 bool os::Bsd::is_sig_ignored(int sig) {
562 struct sigaction oact;
563 sigaction(sig, (struct sigaction*)NULL, &oact);
564 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
565 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
566 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
567 return true;
568 else
569 return false;
570 }
571
572 void os::Bsd::signal_sets_init() {
573 // Should also have an assertion stating we are still single-threaded.
574 assert(!signal_sets_initialized, "Already initialized");
575 // Fill in signals that are necessarily unblocked for all threads in
576 // the VM. Currently, we unblock the following signals:
577 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
578 // by -Xrs (=ReduceSignalUsage));
579 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
580 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
581 // the dispositions or masks wrt these signals.
582 // Programs embedding the VM that want to use the above signals for their
583 // own purposes must, at this time, use the "-Xrs" option to prevent
584 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
585 // (See bug 4345157, and other related bugs).
586 // In reality, though, unblocking these signals is really a nop, since
587 // these signals are not blocked by default.
588 sigemptyset(&unblocked_sigs);
589 sigemptyset(&allowdebug_blocked_sigs);
590 sigaddset(&unblocked_sigs, SIGILL);
591 sigaddset(&unblocked_sigs, SIGSEGV);
592 sigaddset(&unblocked_sigs, SIGBUS);
593 sigaddset(&unblocked_sigs, SIGFPE);
594 sigaddset(&unblocked_sigs, SR_signum);
595
596 if (!ReduceSignalUsage) {
597 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
598 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
599 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
600 }
601 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
602 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
603 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
604 }
605 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
606 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
607 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
608 }
609 }
610 // Fill in signals that are blocked by all but the VM thread.
611 sigemptyset(&vm_sigs);
612 if (!ReduceSignalUsage)
613 sigaddset(&vm_sigs, BREAK_SIGNAL);
614 debug_only(signal_sets_initialized = true);
615
616 }
617
618 // These are signals that are unblocked while a thread is running Java.
619 // (For some reason, they get blocked by default.)
620 sigset_t* os::Bsd::unblocked_signals() {
621 assert(signal_sets_initialized, "Not initialized");
622 return &unblocked_sigs;
623 }
624
625 // These are the signals that are blocked while a (non-VM) thread is
626 // running Java. Only the VM thread handles these signals.
627 sigset_t* os::Bsd::vm_signals() {
628 assert(signal_sets_initialized, "Not initialized");
629 return &vm_sigs;
630 }
631
632 // These are signals that are blocked during cond_wait to allow debugger in
633 sigset_t* os::Bsd::allowdebug_blocked_signals() {
634 assert(signal_sets_initialized, "Not initialized");
635 return &allowdebug_blocked_sigs;
636 }
637
638 void os::Bsd::hotspot_sigmask(Thread* thread) {
639
640 //Save caller's signal mask before setting VM signal mask
641 sigset_t caller_sigmask;
642 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
643
644 OSThread* osthread = thread->osthread();
645 osthread->set_caller_sigmask(caller_sigmask);
646
647 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
648
649 if (!ReduceSignalUsage) {
650 if (thread->is_VM_thread()) {
651 // Only the VM thread handles BREAK_SIGNAL ...
652 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
653 } else {
654 // ... all other threads block BREAK_SIGNAL
655 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
656 }
657 }
658 }
659
660
661 //////////////////////////////////////////////////////////////////////////////
662 // create new thread
663
664 // check if it's safe to start a new thread
665 static bool _thread_safety_check(Thread* thread) {
666 return true;
667 }
668
669 #ifdef __APPLE__
670 // library handle for calling objc_registerThreadWithCollector()
671 // without static linking to the libobjc library
672 #define OBJC_LIB "/usr/lib/libobjc.dylib"
673 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
674 typedef void (*objc_registerThreadWithCollector_t)();
675 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
676 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
677 #endif
678
679 #ifdef __APPLE__
680 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
681 // Additional thread_id used to correlate threads in SA
682 thread_identifier_info_data_t m_ident_info;
683 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
684
685 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
686 (thread_info_t) &m_ident_info, &count);
687
688 return m_ident_info.thread_id;
689 }
690 #endif
691
692 // Thread start routine for all newly created threads
693 static void *java_start(Thread *thread) {
694 // Try to randomize the cache line index of hot stack frames.
695 // This helps when threads of the same stack traces evict each other's
696 // cache lines. The threads can be either from the same JVM instance, or
697 // from different JVM instances. The benefit is especially true for
698 // processors with hyperthreading technology.
699 static int counter = 0;
700 int pid = os::current_process_id();
701 alloca(((pid ^ counter++) & 7) * 128);
702
703 ThreadLocalStorage::set_thread(thread);
704
705 OSThread* osthread = thread->osthread();
706 Monitor* sync = osthread->startThread_lock();
707
708 // non floating stack BsdThreads needs extra check, see above
709 if (!_thread_safety_check(thread)) {
710 // notify parent thread
711 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
712 osthread->set_state(ZOMBIE);
713 sync->notify_all();
714 return NULL;
715 }
716
717 osthread->set_thread_id(os::Bsd::gettid());
718
719 #ifdef __APPLE__
720 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
721 guarantee(unique_thread_id != 0, "unique thread id was not found");
722 osthread->set_unique_thread_id(unique_thread_id);
723 #endif
724 // initialize signal mask for this thread
725 os::Bsd::hotspot_sigmask(thread);
726
727 // initialize floating point control register
728 os::Bsd::init_thread_fpu_state();
729
730 #ifdef __APPLE__
731 // register thread with objc gc
732 if (objc_registerThreadWithCollectorFunction != NULL) {
733 objc_registerThreadWithCollectorFunction();
734 }
735 #endif
736
737 // handshaking with parent thread
738 {
739 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
740
741 // notify parent thread
742 osthread->set_state(INITIALIZED);
743 sync->notify_all();
744
745 // wait until os::start_thread()
746 while (osthread->get_state() == INITIALIZED) {
747 sync->wait(Mutex::_no_safepoint_check_flag);
748 }
749 }
750
751 // call one more level start routine
752 thread->run();
753
754 return 0;
755 }
756
757 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
758 assert(thread->osthread() == NULL, "caller responsible");
759
760 // Allocate the OSThread object
761 OSThread* osthread = new OSThread(NULL, NULL);
762 if (osthread == NULL) {
763 return false;
764 }
765
766 // set the correct thread state
767 osthread->set_thread_type(thr_type);
768
769 // Initial state is ALLOCATED but not INITIALIZED
770 osthread->set_state(ALLOCATED);
771
772 thread->set_osthread(osthread);
773
774 // init thread attributes
775 pthread_attr_t attr;
776 pthread_attr_init(&attr);
777 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
778
779 // stack size
780 if (os::Bsd::supports_variable_stack_size()) {
781 // calculate stack size if it's not specified by caller
782 if (stack_size == 0) {
783 stack_size = os::Bsd::default_stack_size(thr_type);
784
785 switch (thr_type) {
786 case os::java_thread:
787 // Java threads use ThreadStackSize which default value can be
788 // changed with the flag -Xss
789 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
790 stack_size = JavaThread::stack_size_at_create();
791 break;
792 case os::compiler_thread:
793 if (CompilerThreadStackSize > 0) {
794 stack_size = (size_t)(CompilerThreadStackSize * K);
795 break;
796 } // else fall through:
797 // use VMThreadStackSize if CompilerThreadStackSize is not defined
798 case os::vm_thread:
799 case os::pgc_thread:
800 case os::cgc_thread:
801 case os::watcher_thread:
802 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
803 break;
804 }
805 }
806
807 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
808 pthread_attr_setstacksize(&attr, stack_size);
809 } else {
810 // let pthread_create() pick the default value.
811 }
812
813 ThreadState state;
814
815 {
816 pthread_t tid;
817 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
818
819 pthread_attr_destroy(&attr);
820
821 if (ret != 0) {
822 if (PrintMiscellaneous && (Verbose || WizardMode)) {
823 perror("pthread_create()");
824 }
825 // Need to clean up stuff we've allocated so far
826 thread->set_osthread(NULL);
827 delete osthread;
828 return false;
829 }
830
831 // Store pthread info into the OSThread
832 osthread->set_pthread_id(tid);
833
834 // Wait until child thread is either initialized or aborted
835 {
836 Monitor* sync_with_child = osthread->startThread_lock();
837 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
838 while ((state = osthread->get_state()) == ALLOCATED) {
839 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
840 }
841 }
842
843 }
844
845 // Aborted due to thread limit being reached
846 if (state == ZOMBIE) {
847 thread->set_osthread(NULL);
848 delete osthread;
849 return false;
850 }
851
852 // The thread is returned suspended (in state INITIALIZED),
853 // and is started higher up in the call chain
854 assert(state == INITIALIZED, "race condition");
855 return true;
856 }
857
858 /////////////////////////////////////////////////////////////////////////////
859 // attach existing thread
860
861 // bootstrap the main thread
862 bool os::create_main_thread(JavaThread* thread) {
863 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
864 return create_attached_thread(thread);
865 }
866
867 bool os::create_attached_thread(JavaThread* thread) {
868 #ifdef ASSERT
869 thread->verify_not_published();
870 #endif
871
872 // Allocate the OSThread object
873 OSThread* osthread = new OSThread(NULL, NULL);
874
875 if (osthread == NULL) {
876 return false;
877 }
878
879 osthread->set_thread_id(os::Bsd::gettid());
880
881 // Store pthread info into the OSThread
882 #ifdef __APPLE__
883 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
884 guarantee(unique_thread_id != 0, "just checking");
885 osthread->set_unique_thread_id(unique_thread_id);
886 #endif
887 osthread->set_pthread_id(::pthread_self());
888
889 // initialize floating point control register
890 os::Bsd::init_thread_fpu_state();
891
892 // Initial thread state is RUNNABLE
893 osthread->set_state(RUNNABLE);
894
895 thread->set_osthread(osthread);
896
897 // initialize signal mask for this thread
898 // and save the caller's signal mask
899 os::Bsd::hotspot_sigmask(thread);
900
901 return true;
902 }
903
904 void os::pd_start_thread(Thread* thread) {
905 OSThread * osthread = thread->osthread();
906 assert(osthread->get_state() != INITIALIZED, "just checking");
907 Monitor* sync_with_child = osthread->startThread_lock();
908 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
909 sync_with_child->notify();
910 }
911
912 // Free Bsd resources related to the OSThread
913 void os::free_thread(OSThread* osthread) {
914 assert(osthread != NULL, "osthread not set");
915
916 if (Thread::current()->osthread() == osthread) {
917 // Restore caller's signal mask
918 sigset_t sigmask = osthread->caller_sigmask();
919 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
920 }
921
922 delete osthread;
923 }
924
925 //////////////////////////////////////////////////////////////////////////////
926 // thread local storage
927
928 // Restore the thread pointer if the destructor is called. This is in case
929 // someone from JNI code sets up a destructor with pthread_key_create to run
930 // detachCurrentThread on thread death. Unless we restore the thread pointer we
931 // will hang or crash. When detachCurrentThread is called the key will be set
932 // to null and we will not be called again. If detachCurrentThread is never
933 // called we could loop forever depending on the pthread implementation.
934 static void restore_thread_pointer(void* p) {
935 Thread* thread = (Thread*) p;
936 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
937 }
938
939 int os::allocate_thread_local_storage() {
940 pthread_key_t key;
941 int rslt = pthread_key_create(&key, restore_thread_pointer);
942 assert(rslt == 0, "cannot allocate thread local storage");
943 return (int)key;
944 }
945
946 // Note: This is currently not used by VM, as we don't destroy TLS key
947 // on VM exit.
948 void os::free_thread_local_storage(int index) {
949 int rslt = pthread_key_delete((pthread_key_t)index);
950 assert(rslt == 0, "invalid index");
951 }
952
953 void os::thread_local_storage_at_put(int index, void* value) {
954 int rslt = pthread_setspecific((pthread_key_t)index, value);
955 assert(rslt == 0, "pthread_setspecific failed");
956 }
957
958 extern "C" Thread* get_thread() {
959 return ThreadLocalStorage::thread();
960 }
961
962
963 ////////////////////////////////////////////////////////////////////////////////
964 // time support
965
966 // Time since start-up in seconds to a fine granularity.
967 // Used by VMSelfDestructTimer and the MemProfiler.
968 double os::elapsedTime() {
969
970 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
971 }
972
973 jlong os::elapsed_counter() {
974 return javaTimeNanos() - initial_time_count;
975 }
976
977 jlong os::elapsed_frequency() {
978 return NANOSECS_PER_SEC; // nanosecond resolution
979 }
980
981 bool os::supports_vtime() { return true; }
982 bool os::enable_vtime() { return false; }
983 bool os::vtime_enabled() { return false; }
984
985 double os::elapsedVTime() {
986 // better than nothing, but not much
987 return elapsedTime();
988 }
989
990 jlong os::javaTimeMillis() {
991 timeval time;
992 int status = gettimeofday(&time, NULL);
993 assert(status != -1, "bsd error");
994 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
995 }
996
997 #ifndef __APPLE__
998 #ifndef CLOCK_MONOTONIC
999 #define CLOCK_MONOTONIC (1)
1000 #endif
1001 #endif
1002
1003 #ifdef __APPLE__
1004 void os::Bsd::clock_init() {
1005 mach_timebase_info(&_timebase_info);
1006 }
1007 #else
1008 void os::Bsd::clock_init() {
1009 struct timespec res;
1010 struct timespec tp;
1011 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
1012 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
1013 // yes, monotonic clock is supported
1014 _clock_gettime = ::clock_gettime;
1015 }
1016 }
1017 #endif
1018
1019
1020 #ifdef __APPLE__
1021
1022 jlong os::javaTimeNanos() {
1023 const uint64_t tm = mach_absolute_time();
1024 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
1025 const uint64_t prev = Bsd::_max_abstime;
1026 if (now <= prev) {
1027 return prev; // same or retrograde time;
1028 }
1029 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
1030 assert(obsv >= prev, "invariant"); // Monotonicity
1031 // If the CAS succeeded then we're done and return "now".
1032 // If the CAS failed and the observed value "obsv" is >= now then
1033 // we should return "obsv". If the CAS failed and now > obsv > prv then
1034 // some other thread raced this thread and installed a new value, in which case
1035 // we could either (a) retry the entire operation, (b) retry trying to install now
1036 // or (c) just return obsv. We use (c). No loop is required although in some cases
1037 // we might discard a higher "now" value in deference to a slightly lower but freshly
1038 // installed obsv value. That's entirely benign -- it admits no new orderings compared
1039 // to (a) or (b) -- and greatly reduces coherence traffic.
1040 // We might also condition (c) on the magnitude of the delta between obsv and now.
1041 // Avoiding excessive CAS operations to hot RW locations is critical.
1042 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1043 return (prev == obsv) ? now : obsv;
1044 }
1045
1046 #else // __APPLE__
1047
1048 jlong os::javaTimeNanos() {
1049 if (Bsd::supports_monotonic_clock()) {
1050 struct timespec tp;
1051 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1052 assert(status == 0, "gettime error");
1053 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1054 return result;
1055 } else {
1056 timeval time;
1057 int status = gettimeofday(&time, NULL);
1058 assert(status != -1, "bsd error");
1059 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1060 return 1000 * usecs;
1061 }
1062 }
1063
1064 #endif // __APPLE__
1065
1066 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1067 if (Bsd::supports_monotonic_clock()) {
1068 info_ptr->max_value = ALL_64_BITS;
1069
1070 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1071 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1072 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1073 } else {
1074 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1075 info_ptr->max_value = ALL_64_BITS;
1076
1077 // gettimeofday is a real time clock so it skips
1078 info_ptr->may_skip_backward = true;
1079 info_ptr->may_skip_forward = true;
1080 }
1081
1082 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1083 }
1084
1085 // Return the real, user, and system times in seconds from an
1086 // arbitrary fixed point in the past.
1087 bool os::getTimesSecs(double* process_real_time,
1088 double* process_user_time,
1089 double* process_system_time) {
1090 struct tms ticks;
1091 clock_t real_ticks = times(&ticks);
1092
1093 if (real_ticks == (clock_t) (-1)) {
1094 return false;
1095 } else {
1096 double ticks_per_second = (double) clock_tics_per_sec;
1097 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1098 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1099 *process_real_time = ((double) real_ticks) / ticks_per_second;
1100
1101 return true;
1102 }
1103 }
1104
1105
1106 char * os::local_time_string(char *buf, size_t buflen) {
1107 struct tm t;
1108 time_t long_time;
1109 time(&long_time);
1110 localtime_r(&long_time, &t);
1111 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1112 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1113 t.tm_hour, t.tm_min, t.tm_sec);
1114 return buf;
1115 }
1116
1117 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1118 return localtime_r(clock, res);
1119 }
1120
1121 ////////////////////////////////////////////////////////////////////////////////
1122 // runtime exit support
1123
1124 // Note: os::shutdown() might be called very early during initialization, or
1125 // called from signal handler. Before adding something to os::shutdown(), make
1126 // sure it is async-safe and can handle partially initialized VM.
1127 void os::shutdown() {
1128
1129 // allow PerfMemory to attempt cleanup of any persistent resources
1130 perfMemory_exit();
1131
1132 // needs to remove object in file system
1133 AttachListener::abort();
1134
1135 // flush buffered output, finish log files
1136 ostream_abort();
1137
1138 // Check for abort hook
1139 abort_hook_t abort_hook = Arguments::abort_hook();
1140 if (abort_hook != NULL) {
1141 abort_hook();
1142 }
1143
1144 }
1145
1146 // Note: os::abort() might be called very early during initialization, or
1147 // called from signal handler. Before adding something to os::abort(), make
1148 // sure it is async-safe and can handle partially initialized VM.
1149 void os::abort(bool dump_core) {
1150 os::shutdown();
1151 if (dump_core) {
1152 #ifndef PRODUCT
1153 fdStream out(defaultStream::output_fd());
1154 out.print_raw("Current thread is ");
1155 char buf[16];
1156 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1157 out.print_raw_cr(buf);
1158 out.print_raw_cr("Dumping core ...");
1159 #endif
1160 ::abort(); // dump core
1161 }
1162
1163 ::exit(1);
1164 }
1165
1166 // Die immediately, no exit hook, no abort hook, no cleanup.
1167 void os::die() {
1168 // _exit() on BsdThreads only kills current thread
1169 ::abort();
1170 }
1171
1172 // This method is a copy of JDK's sysGetLastErrorString
1173 // from src/solaris/hpi/src/system_md.c
1174
1175 size_t os::lasterror(char *buf, size_t len) {
1176
1177 if (errno == 0) return 0;
1178
1179 const char *s = ::strerror(errno);
1180 size_t n = ::strlen(s);
1181 if (n >= len) {
1182 n = len - 1;
1183 }
1184 ::strncpy(buf, s, n);
1185 buf[n] = '\0';
1186 return n;
1187 }
1188
1189 // Information of current thread in variety of formats
1190 pid_t os::Bsd::gettid() {
1191 int retval = -1;
1192
1193 #ifdef __APPLE__ //XNU kernel
1194 // despite the fact mach port is actually not a thread id use it
1195 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1196 retval = ::pthread_mach_thread_np(::pthread_self());
1197 guarantee(retval != 0, "just checking");
1198 return retval;
1199
1200 #else
1201 #ifdef __FreeBSD__
1202 retval = syscall(SYS_thr_self);
1203 #else
1204 #ifdef __OpenBSD__
1205 retval = syscall(SYS_getthrid);
1206 #else
1207 #ifdef __NetBSD__
1208 retval = (pid_t) syscall(SYS__lwp_self);
1209 #endif
1210 #endif
1211 #endif
1212 #endif
1213
1214 if (retval == -1) {
1215 return getpid();
1216 }
1217 }
1218
1219 intx os::current_thread_id() {
1220 #ifdef __APPLE__
1221 return (intx)::pthread_mach_thread_np(::pthread_self());
1222 #else
1223 return (intx)::pthread_self();
1224 #endif
1225 }
1226
1227 int os::current_process_id() {
1228
1229 // Under the old bsd thread library, bsd gives each thread
1230 // its own process id. Because of this each thread will return
1231 // a different pid if this method were to return the result
1232 // of getpid(2). Bsd provides no api that returns the pid
1233 // of the launcher thread for the vm. This implementation
1234 // returns a unique pid, the pid of the launcher thread
1235 // that starts the vm 'process'.
1236
1237 // Under the NPTL, getpid() returns the same pid as the
1238 // launcher thread rather than a unique pid per thread.
1239 // Use gettid() if you want the old pre NPTL behaviour.
1240
1241 // if you are looking for the result of a call to getpid() that
1242 // returns a unique pid for the calling thread, then look at the
1243 // OSThread::thread_id() method in osThread_bsd.hpp file
1244
1245 return (int)(_initial_pid ? _initial_pid : getpid());
1246 }
1247
1248 // DLL functions
1249
1250 #define JNI_LIB_PREFIX "lib"
1251 #ifdef __APPLE__
1252 #define JNI_LIB_SUFFIX ".dylib"
1253 #else
1254 #define JNI_LIB_SUFFIX ".so"
1255 #endif
1256
1257 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1258
1259 // This must be hard coded because it's the system's temporary
1260 // directory not the java application's temp directory, ala java.io.tmpdir.
1261 #ifdef __APPLE__
1262 // macosx has a secure per-user temporary directory
1263 char temp_path_storage[PATH_MAX];
1264 const char* os::get_temp_directory() {
1265 static char *temp_path = NULL;
1266 if (temp_path == NULL) {
1267 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1268 if (pathSize == 0 || pathSize > PATH_MAX) {
1269 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1270 }
1271 temp_path = temp_path_storage;
1272 }
1273 return temp_path;
1274 }
1275 #else /* __APPLE__ */
1276 const char* os::get_temp_directory() { return "/tmp"; }
1277 #endif /* __APPLE__ */
1278
1279 static bool file_exists(const char* filename) {
1280 struct stat statbuf;
1281 if (filename == NULL || strlen(filename) == 0) {
1282 return false;
1283 }
1284 return os::stat(filename, &statbuf) == 0;
1285 }
1286
1287 bool os::dll_build_name(char* buffer, size_t buflen,
1288 const char* pname, const char* fname) {
1289 bool retval = false;
1290 // Copied from libhpi
1291 const size_t pnamelen = pname ? strlen(pname) : 0;
1292
1293 // Return error on buffer overflow.
1294 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1295 return retval;
1296 }
1297
1298 if (pnamelen == 0) {
1299 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1300 retval = true;
1301 } else if (strchr(pname, *os::path_separator()) != NULL) {
1302 int n;
1303 char** pelements = split_path(pname, &n);
1304 if (pelements == NULL) {
1305 return false;
1306 }
1307 for (int i = 0 ; i < n ; i++) {
1308 // Really shouldn't be NULL, but check can't hurt
1309 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1310 continue; // skip the empty path values
1311 }
1312 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1313 pelements[i], fname);
1314 if (file_exists(buffer)) {
1315 retval = true;
1316 break;
1317 }
1318 }
1319 // release the storage
1320 for (int i = 0 ; i < n ; i++) {
1321 if (pelements[i] != NULL) {
1322 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1323 }
1324 }
1325 if (pelements != NULL) {
1326 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1327 }
1328 } else {
1329 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1330 retval = true;
1331 }
1332 return retval;
1333 }
1334
1335 // check if addr is inside libjvm.so
1336 bool os::address_is_in_vm(address addr) {
1337 static address libjvm_base_addr;
1338 Dl_info dlinfo;
1339
1340 if (libjvm_base_addr == NULL) {
1341 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1342 libjvm_base_addr = (address)dlinfo.dli_fbase;
1343 }
1344 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1345 }
1346
1347 if (dladdr((void *)addr, &dlinfo) != 0) {
1348 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1349 }
1350
1351 return false;
1352 }
1353
1354
1355 #define MACH_MAXSYMLEN 256
1356
1357 bool os::dll_address_to_function_name(address addr, char *buf,
1358 int buflen, int *offset) {
1359 // buf is not optional, but offset is optional
1360 assert(buf != NULL, "sanity check");
1361
1362 Dl_info dlinfo;
1363 char localbuf[MACH_MAXSYMLEN];
1364
1365 if (dladdr((void*)addr, &dlinfo) != 0) {
1366 // see if we have a matching symbol
1367 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1368 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1369 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1370 }
1371 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1372 return true;
1373 }
1374 // no matching symbol so try for just file info
1375 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1376 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1377 buf, buflen, offset, dlinfo.dli_fname)) {
1378 return true;
1379 }
1380 }
1381
1382 // Handle non-dynamic manually:
1383 if (dlinfo.dli_fbase != NULL &&
1384 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1385 dlinfo.dli_fbase)) {
1386 if (!Decoder::demangle(localbuf, buf, buflen)) {
1387 jio_snprintf(buf, buflen, "%s", localbuf);
1388 }
1389 return true;
1390 }
1391 }
1392 buf[0] = '\0';
1393 if (offset != NULL) *offset = -1;
1394 return false;
1395 }
1396
1397 // ported from solaris version
1398 bool os::dll_address_to_library_name(address addr, char* buf,
1399 int buflen, int* offset) {
1400 // buf is not optional, but offset is optional
1401 assert(buf != NULL, "sanity check");
1402
1403 Dl_info dlinfo;
1404
1405 if (dladdr((void*)addr, &dlinfo) != 0) {
1406 if (dlinfo.dli_fname != NULL) {
1407 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1408 }
1409 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1410 *offset = addr - (address)dlinfo.dli_fbase;
1411 }
1412 return true;
1413 }
1414
1415 buf[0] = '\0';
1416 if (offset) *offset = -1;
1417 return false;
1418 }
1419
1420 // Loads .dll/.so and
1421 // in case of error it checks if .dll/.so was built for the
1422 // same architecture as Hotspot is running on
1423
1424 #ifdef __APPLE__
1425 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1426 void * result= ::dlopen(filename, RTLD_LAZY);
1427 if (result != NULL) {
1428 // Successful loading
1429 return result;
1430 }
1431
1432 // Read system error message into ebuf
1433 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1434 ebuf[ebuflen-1]='\0';
1435
1436 return NULL;
1437 }
1438 #else
1439 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1440 {
1441 void * result= ::dlopen(filename, RTLD_LAZY);
1442 if (result != NULL) {
1443 // Successful loading
1444 return result;
1445 }
1446
1447 Elf32_Ehdr elf_head;
1448
1449 // Read system error message into ebuf
1450 // It may or may not be overwritten below
1451 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1452 ebuf[ebuflen-1]='\0';
1453 int diag_msg_max_length=ebuflen-strlen(ebuf);
1454 char* diag_msg_buf=ebuf+strlen(ebuf);
1455
1456 if (diag_msg_max_length==0) {
1457 // No more space in ebuf for additional diagnostics message
1458 return NULL;
1459 }
1460
1461
1462 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1463
1464 if (file_descriptor < 0) {
1465 // Can't open library, report dlerror() message
1466 return NULL;
1467 }
1468
1469 bool failed_to_read_elf_head=
1470 (sizeof(elf_head)!=
1471 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1472
1473 ::close(file_descriptor);
1474 if (failed_to_read_elf_head) {
1475 // file i/o error - report dlerror() msg
1476 return NULL;
1477 }
1478
1479 typedef struct {
1480 Elf32_Half code; // Actual value as defined in elf.h
1481 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1482 char elf_class; // 32 or 64 bit
1483 char endianess; // MSB or LSB
1484 char* name; // String representation
1485 } arch_t;
1486
1487 #ifndef EM_486
1488 #define EM_486 6 /* Intel 80486 */
1489 #endif
1490
1491 #ifndef EM_MIPS_RS3_LE
1492 #define EM_MIPS_RS3_LE 10 /* MIPS */
1493 #endif
1494
1495 #ifndef EM_PPC64
1496 #define EM_PPC64 21 /* PowerPC64 */
1497 #endif
1498
1499 #ifndef EM_S390
1500 #define EM_S390 22 /* IBM System/390 */
1501 #endif
1502
1503 #ifndef EM_IA_64
1504 #define EM_IA_64 50 /* HP/Intel IA-64 */
1505 #endif
1506
1507 #ifndef EM_X86_64
1508 #define EM_X86_64 62 /* AMD x86-64 */
1509 #endif
1510
1511 static const arch_t arch_array[]={
1512 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1513 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1514 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1515 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1516 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1517 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1518 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1519 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1520 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1521 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1522 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1523 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1524 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1525 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1526 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1527 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1528 };
1529
1530 #if (defined IA32)
1531 static Elf32_Half running_arch_code=EM_386;
1532 #elif (defined AMD64)
1533 static Elf32_Half running_arch_code=EM_X86_64;
1534 #elif (defined IA64)
1535 static Elf32_Half running_arch_code=EM_IA_64;
1536 #elif (defined __sparc) && (defined _LP64)
1537 static Elf32_Half running_arch_code=EM_SPARCV9;
1538 #elif (defined __sparc) && (!defined _LP64)
1539 static Elf32_Half running_arch_code=EM_SPARC;
1540 #elif (defined __powerpc64__)
1541 static Elf32_Half running_arch_code=EM_PPC64;
1542 #elif (defined __powerpc__)
1543 static Elf32_Half running_arch_code=EM_PPC;
1544 #elif (defined ARM)
1545 static Elf32_Half running_arch_code=EM_ARM;
1546 #elif (defined S390)
1547 static Elf32_Half running_arch_code=EM_S390;
1548 #elif (defined ALPHA)
1549 static Elf32_Half running_arch_code=EM_ALPHA;
1550 #elif (defined MIPSEL)
1551 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1552 #elif (defined PARISC)
1553 static Elf32_Half running_arch_code=EM_PARISC;
1554 #elif (defined MIPS)
1555 static Elf32_Half running_arch_code=EM_MIPS;
1556 #elif (defined M68K)
1557 static Elf32_Half running_arch_code=EM_68K;
1558 #else
1559 #error Method os::dll_load requires that one of following is defined:\
1560 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1561 #endif
1562
1563 // Identify compatability class for VM's architecture and library's architecture
1564 // Obtain string descriptions for architectures
1565
1566 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1567 int running_arch_index=-1;
1568
1569 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1570 if (running_arch_code == arch_array[i].code) {
1571 running_arch_index = i;
1572 }
1573 if (lib_arch.code == arch_array[i].code) {
1574 lib_arch.compat_class = arch_array[i].compat_class;
1575 lib_arch.name = arch_array[i].name;
1576 }
1577 }
1578
1579 assert(running_arch_index != -1,
1580 "Didn't find running architecture code (running_arch_code) in arch_array");
1581 if (running_arch_index == -1) {
1582 // Even though running architecture detection failed
1583 // we may still continue with reporting dlerror() message
1584 return NULL;
1585 }
1586
1587 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1588 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1589 return NULL;
1590 }
1591
1592 #ifndef S390
1593 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1594 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1595 return NULL;
1596 }
1597 #endif // !S390
1598
1599 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1600 if ( lib_arch.name!=NULL ) {
1601 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1602 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1603 lib_arch.name, arch_array[running_arch_index].name);
1604 } else {
1605 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1606 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1607 lib_arch.code,
1608 arch_array[running_arch_index].name);
1609 }
1610 }
1611
1612 return NULL;
1613 }
1614 #endif /* !__APPLE__ */
1615
1616 void* os::get_default_process_handle() {
1617 #ifdef __APPLE__
1618 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1619 // to avoid finding unexpected symbols on second (or later)
1620 // loads of a library.
1621 return (void*)::dlopen(NULL, RTLD_FIRST);
1622 #else
1623 return (void*)::dlopen(NULL, RTLD_LAZY);
1624 #endif
1625 }
1626
1627 // XXX: Do we need a lock around this as per Linux?
1628 void* os::dll_lookup(void* handle, const char* name) {
1629 return dlsym(handle, name);
1630 }
1631
1632
1633 static bool _print_ascii_file(const char* filename, outputStream* st) {
1634 int fd = ::open(filename, O_RDONLY);
1635 if (fd == -1) {
1636 return false;
1637 }
1638
1639 char buf[32];
1640 int bytes;
1641 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1642 st->print_raw(buf, bytes);
1643 }
1644
1645 ::close(fd);
1646
1647 return true;
1648 }
1649
1650 void os::print_dll_info(outputStream *st) {
1651 st->print_cr("Dynamic libraries:");
1652 #ifdef RTLD_DI_LINKMAP
1653 Dl_info dli;
1654 void *handle;
1655 Link_map *map;
1656 Link_map *p;
1657
1658 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1659 dli.dli_fname == NULL) {
1660 st->print_cr("Error: Cannot print dynamic libraries.");
1661 return;
1662 }
1663 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1664 if (handle == NULL) {
1665 st->print_cr("Error: Cannot print dynamic libraries.");
1666 return;
1667 }
1668 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1669 if (map == NULL) {
1670 st->print_cr("Error: Cannot print dynamic libraries.");
1671 return;
1672 }
1673
1674 while (map->l_prev != NULL)
1675 map = map->l_prev;
1676
1677 while (map != NULL) {
1678 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1679 map = map->l_next;
1680 }
1681
1682 dlclose(handle);
1683 #elif defined(__APPLE__)
1684 uint32_t count;
1685 uint32_t i;
1686
1687 count = _dyld_image_count();
1688 for (i = 1; i < count; i++) {
1689 const char *name = _dyld_get_image_name(i);
1690 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1691 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1692 }
1693 #else
1694 st->print_cr("Error: Cannot print dynamic libraries.");
1695 #endif
1696 }
1697
1698 void os::print_os_info_brief(outputStream* st) {
1699 st->print("Bsd");
1700
1701 os::Posix::print_uname_info(st);
1702 }
1703
1704 void os::print_os_info(outputStream* st) {
1705 st->print("OS:");
1706 st->print("Bsd");
1707
1708 os::Posix::print_uname_info(st);
1709
1710 os::Posix::print_rlimit_info(st);
1711
1712 os::Posix::print_load_average(st);
1713 }
1714
1715 void os::pd_print_cpu_info(outputStream* st) {
1716 // Nothing to do for now.
1717 }
1718
1719 void os::print_memory_info(outputStream* st) {
1720
1721 st->print("Memory:");
1722 st->print(" %dk page", os::vm_page_size()>>10);
1723
1724 st->print(", physical " UINT64_FORMAT "k",
1725 os::physical_memory() >> 10);
1726 st->print("(" UINT64_FORMAT "k free)",
1727 os::available_memory() >> 10);
1728 st->cr();
1729
1730 // meminfo
1731 st->print("\n/proc/meminfo:\n");
1732 _print_ascii_file("/proc/meminfo", st);
1733 st->cr();
1734 }
1735
1736 void os::print_siginfo(outputStream* st, void* siginfo) {
1737 const siginfo_t* si = (const siginfo_t*)siginfo;
1738
1739 os::Posix::print_siginfo_brief(st, si);
1740
1741 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1742 UseSharedSpaces) {
1743 FileMapInfo* mapinfo = FileMapInfo::current_info();
1744 if (mapinfo->is_in_shared_space(si->si_addr)) {
1745 st->print("\n\nError accessing class data sharing archive." \
1746 " Mapped file inaccessible during execution, " \
1747 " possible disk/network problem.");
1748 }
1749 }
1750 st->cr();
1751 }
1752
1753
1754 static void print_signal_handler(outputStream* st, int sig,
1755 char* buf, size_t buflen);
1756
1757 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1758 st->print_cr("Signal Handlers:");
1759 print_signal_handler(st, SIGSEGV, buf, buflen);
1760 print_signal_handler(st, SIGBUS , buf, buflen);
1761 print_signal_handler(st, SIGFPE , buf, buflen);
1762 print_signal_handler(st, SIGPIPE, buf, buflen);
1763 print_signal_handler(st, SIGXFSZ, buf, buflen);
1764 print_signal_handler(st, SIGILL , buf, buflen);
1765 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1766 print_signal_handler(st, SR_signum, buf, buflen);
1767 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1768 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1769 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1770 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1771 }
1772
1773 static char saved_jvm_path[MAXPATHLEN] = {0};
1774
1775 // Find the full path to the current module, libjvm
1776 void os::jvm_path(char *buf, jint buflen) {
1777 // Error checking.
1778 if (buflen < MAXPATHLEN) {
1779 assert(false, "must use a large-enough buffer");
1780 buf[0] = '\0';
1781 return;
1782 }
1783 // Lazy resolve the path to current module.
1784 if (saved_jvm_path[0] != 0) {
1785 strcpy(buf, saved_jvm_path);
1786 return;
1787 }
1788
1789 char dli_fname[MAXPATHLEN];
1790 bool ret = dll_address_to_library_name(
1791 CAST_FROM_FN_PTR(address, os::jvm_path),
1792 dli_fname, sizeof(dli_fname), NULL);
1793 assert(ret, "cannot locate libjvm");
1794 char *rp = NULL;
1795 if (ret && dli_fname[0] != '\0') {
1796 rp = realpath(dli_fname, buf);
1797 }
1798 if (rp == NULL)
1799 return;
1800
1801 if (Arguments::created_by_gamma_launcher()) {
1802 // Support for the gamma launcher. Typical value for buf is
1803 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1804 // the right place in the string, then assume we are installed in a JDK and
1805 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1806 // construct a path to the JVM being overridden.
1807
1808 const char *p = buf + strlen(buf) - 1;
1809 for (int count = 0; p > buf && count < 5; ++count) {
1810 for (--p; p > buf && *p != '/'; --p)
1811 /* empty */ ;
1812 }
1813
1814 if (strncmp(p, "/jre/lib/", 9) != 0) {
1815 // Look for JAVA_HOME in the environment.
1816 char* java_home_var = ::getenv("JAVA_HOME");
1817 if (java_home_var != NULL && java_home_var[0] != 0) {
1818 char* jrelib_p;
1819 int len;
1820
1821 // Check the current module name "libjvm"
1822 p = strrchr(buf, '/');
1823 assert(strstr(p, "/libjvm") == p, "invalid library name");
1824
1825 rp = realpath(java_home_var, buf);
1826 if (rp == NULL)
1827 return;
1828
1829 // determine if this is a legacy image or modules image
1830 // modules image doesn't have "jre" subdirectory
1831 len = strlen(buf);
1832 assert(len < buflen, "Ran out of buffer space");
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, "");
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 strncpy(saved_jvm_path, buf, MAXPATHLEN);
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
2401 // Create a large shared memory region to attach to based on size.
2402 // Currently, size is the total size of the heap
2403 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2404 if (shmid == -1) {
2405 // Possible reasons for shmget failure:
2406 // 1. shmmax is too small for Java heap.
2407 // > check shmmax value: cat /proc/sys/kernel/shmmax
2408 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2409 // 2. not enough large page memory.
2410 // > check available large pages: cat /proc/meminfo
2411 // > increase amount of large pages:
2412 // echo new_value > /proc/sys/vm/nr_hugepages
2413 // Note 1: different Bsd may use different name for this property,
2414 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2415 // Note 2: it's possible there's enough physical memory available but
2416 // they are so fragmented after a long run that they can't
2417 // coalesce into large pages. Try to reserve large pages when
2418 // the system is still "fresh".
2419 if (warn_on_failure) {
2420 warning("Failed to reserve shared memory (errno = %d).", errno);
2421 }
2422 return NULL;
2423 }
2424
2425 // attach to the region
2426 addr = (char*)shmat(shmid, req_addr, 0);
2427 int err = errno;
2428
2429 // Remove shmid. If shmat() is successful, the actual shared memory segment
2430 // will be deleted when it's detached by shmdt() or when the process
2431 // terminates. If shmat() is not successful this will remove the shared
2432 // segment immediately.
2433 shmctl(shmid, IPC_RMID, NULL);
2434
2435 if ((intptr_t)addr == -1) {
2436 if (warn_on_failure) {
2437 warning("Failed to attach shared memory (errno = %d).", err);
2438 }
2439 return NULL;
2440 }
2441
2442 // The memory is committed
2443 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2444
2445 return addr;
2446 }
2447
2448 bool os::release_memory_special(char* base, size_t bytes) {
2449 if (MemTracker::tracking_level() > NMT_minimal) {
2450 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2451 // detaching the SHM segment will also delete it, see reserve_memory_special()
2452 int rslt = shmdt(base);
2453 if (rslt == 0) {
2454 tkr.record((address)base, bytes);
2455 return true;
2456 } else {
2457 return false;
2458 }
2459 } else {
2460 return shmdt(base) == 0;
2461 }
2462 }
2463
2464 size_t os::large_page_size() {
2465 return _large_page_size;
2466 }
2467
2468 // HugeTLBFS allows application to commit large page memory on demand;
2469 // with SysV SHM the entire memory region must be allocated as shared
2470 // memory.
2471 bool os::can_commit_large_page_memory() {
2472 return UseHugeTLBFS;
2473 }
2474
2475 bool os::can_execute_large_page_memory() {
2476 return UseHugeTLBFS;
2477 }
2478
2479 // Reserve memory at an arbitrary address, only if that area is
2480 // available (and not reserved for something else).
2481
2482 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2483 const int max_tries = 10;
2484 char* base[max_tries];
2485 size_t size[max_tries];
2486 const size_t gap = 0x000000;
2487
2488 // Assert only that the size is a multiple of the page size, since
2489 // that's all that mmap requires, and since that's all we really know
2490 // about at this low abstraction level. If we need higher alignment,
2491 // we can either pass an alignment to this method or verify alignment
2492 // in one of the methods further up the call chain. See bug 5044738.
2493 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2494
2495 // Repeatedly allocate blocks until the block is allocated at the
2496 // right spot. Give up after max_tries. Note that reserve_memory() will
2497 // automatically update _highest_vm_reserved_address if the call is
2498 // successful. The variable tracks the highest memory address every reserved
2499 // by JVM. It is used to detect heap-stack collision if running with
2500 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2501 // space than needed, it could confuse the collision detecting code. To
2502 // solve the problem, save current _highest_vm_reserved_address and
2503 // calculate the correct value before return.
2504 address old_highest = _highest_vm_reserved_address;
2505
2506 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2507 // if kernel honors the hint then we can return immediately.
2508 char * addr = anon_mmap(requested_addr, bytes, false);
2509 if (addr == requested_addr) {
2510 return requested_addr;
2511 }
2512
2513 if (addr != NULL) {
2514 // mmap() is successful but it fails to reserve at the requested address
2515 anon_munmap(addr, bytes);
2516 }
2517
2518 int i;
2519 for (i = 0; i < max_tries; ++i) {
2520 base[i] = reserve_memory(bytes);
2521
2522 if (base[i] != NULL) {
2523 // Is this the block we wanted?
2524 if (base[i] == requested_addr) {
2525 size[i] = bytes;
2526 break;
2527 }
2528
2529 // Does this overlap the block we wanted? Give back the overlapped
2530 // parts and try again.
2531
2532 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2533 if (top_overlap >= 0 && top_overlap < bytes) {
2534 unmap_memory(base[i], top_overlap);
2535 base[i] += top_overlap;
2536 size[i] = bytes - top_overlap;
2537 } else {
2538 size_t bottom_overlap = base[i] + bytes - requested_addr;
2539 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2540 unmap_memory(requested_addr, bottom_overlap);
2541 size[i] = bytes - bottom_overlap;
2542 } else {
2543 size[i] = bytes;
2544 }
2545 }
2546 }
2547 }
2548
2549 // Give back the unused reserved pieces.
2550
2551 for (int j = 0; j < i; ++j) {
2552 if (base[j] != NULL) {
2553 unmap_memory(base[j], size[j]);
2554 }
2555 }
2556
2557 if (i < max_tries) {
2558 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2559 return requested_addr;
2560 } else {
2561 _highest_vm_reserved_address = old_highest;
2562 return NULL;
2563 }
2564 }
2565
2566 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2567 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2568 }
2569
2570 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2571 // Solaris uses poll(), bsd uses park().
2572 // Poll() is likely a better choice, assuming that Thread.interrupt()
2573 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2574 // SIGSEGV, see 4355769.
2575
2576 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2577 assert(thread == Thread::current(), "thread consistency check");
2578
2579 ParkEvent * const slp = thread->_SleepEvent ;
2580 slp->reset() ;
2581 OrderAccess::fence() ;
2582
2583 if (interruptible) {
2584 jlong prevtime = javaTimeNanos();
2585
2586 for (;;) {
2587 if (os::is_interrupted(thread, true)) {
2588 return OS_INTRPT;
2589 }
2590
2591 jlong newtime = javaTimeNanos();
2592
2593 if (newtime - prevtime < 0) {
2594 // time moving backwards, should only happen if no monotonic clock
2595 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2596 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2597 } else {
2598 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2599 }
2600
2601 if(millis <= 0) {
2602 return OS_OK;
2603 }
2604
2605 prevtime = newtime;
2606
2607 {
2608 assert(thread->is_Java_thread(), "sanity check");
2609 JavaThread *jt = (JavaThread *) thread;
2610 ThreadBlockInVM tbivm(jt);
2611 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2612
2613 jt->set_suspend_equivalent();
2614 // cleared by handle_special_suspend_equivalent_condition() or
2615 // java_suspend_self() via check_and_wait_while_suspended()
2616
2617 slp->park(millis);
2618
2619 // were we externally suspended while we were waiting?
2620 jt->check_and_wait_while_suspended();
2621 }
2622 }
2623 } else {
2624 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2625 jlong prevtime = javaTimeNanos();
2626
2627 for (;;) {
2628 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2629 // the 1st iteration ...
2630 jlong newtime = javaTimeNanos();
2631
2632 if (newtime - prevtime < 0) {
2633 // time moving backwards, should only happen if no monotonic clock
2634 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2635 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2636 } else {
2637 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2638 }
2639
2640 if(millis <= 0) break ;
2641
2642 prevtime = newtime;
2643 slp->park(millis);
2644 }
2645 return OS_OK ;
2646 }
2647 }
2648
2649 void os::naked_short_sleep(jlong ms) {
2650 struct timespec req;
2651
2652 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2653 req.tv_sec = 0;
2654 if (ms > 0) {
2655 req.tv_nsec = (ms % 1000) * 1000000;
2656 }
2657 else {
2658 req.tv_nsec = 1;
2659 }
2660
2661 nanosleep(&req, NULL);
2662
2663 return;
2664 }
2665
2666 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2667 void os::infinite_sleep() {
2668 while (true) { // sleep forever ...
2669 ::sleep(100); // ... 100 seconds at a time
2670 }
2671 }
2672
2673 // Used to convert frequent JVM_Yield() to nops
2674 bool os::dont_yield() {
2675 return DontYieldALot;
2676 }
2677
2678 void os::yield() {
2679 sched_yield();
2680 }
2681
2682 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2683
2684 void os::yield_all(int attempts) {
2685 // Yields to all threads, including threads with lower priorities
2686 // Threads on Bsd are all with same priority. The Solaris style
2687 // os::yield_all() with nanosleep(1ms) is not necessary.
2688 sched_yield();
2689 }
2690
2691 // Called from the tight loops to possibly influence time-sharing heuristics
2692 void os::loop_breaker(int attempts) {
2693 os::yield_all(attempts);
2694 }
2695
2696 ////////////////////////////////////////////////////////////////////////////////
2697 // thread priority support
2698
2699 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2700 // only supports dynamic priority, static priority must be zero. For real-time
2701 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2702 // However, for large multi-threaded applications, SCHED_RR is not only slower
2703 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2704 // of 5 runs - Sep 2005).
2705 //
2706 // The following code actually changes the niceness of kernel-thread/LWP. It
2707 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2708 // not the entire user process, and user level threads are 1:1 mapped to kernel
2709 // threads. It has always been the case, but could change in the future. For
2710 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2711 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2712
2713 #if !defined(__APPLE__)
2714 int os::java_to_os_priority[CriticalPriority + 1] = {
2715 19, // 0 Entry should never be used
2716
2717 0, // 1 MinPriority
2718 3, // 2
2719 6, // 3
2720
2721 10, // 4
2722 15, // 5 NormPriority
2723 18, // 6
2724
2725 21, // 7
2726 25, // 8
2727 28, // 9 NearMaxPriority
2728
2729 31, // 10 MaxPriority
2730
2731 31 // 11 CriticalPriority
2732 };
2733 #else
2734 /* Using Mach high-level priority assignments */
2735 int os::java_to_os_priority[CriticalPriority + 1] = {
2736 0, // 0 Entry should never be used (MINPRI_USER)
2737
2738 27, // 1 MinPriority
2739 28, // 2
2740 29, // 3
2741
2742 30, // 4
2743 31, // 5 NormPriority (BASEPRI_DEFAULT)
2744 32, // 6
2745
2746 33, // 7
2747 34, // 8
2748 35, // 9 NearMaxPriority
2749
2750 36, // 10 MaxPriority
2751
2752 36 // 11 CriticalPriority
2753 };
2754 #endif
2755
2756 static int prio_init() {
2757 if (ThreadPriorityPolicy == 1) {
2758 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2759 // if effective uid is not root. Perhaps, a more elegant way of doing
2760 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2761 if (geteuid() != 0) {
2762 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2763 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2764 }
2765 ThreadPriorityPolicy = 0;
2766 }
2767 }
2768 if (UseCriticalJavaThreadPriority) {
2769 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2770 }
2771 return 0;
2772 }
2773
2774 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2775 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2776
2777 #ifdef __OpenBSD__
2778 // OpenBSD pthread_setprio starves low priority threads
2779 return OS_OK;
2780 #elif defined(__FreeBSD__)
2781 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2782 #elif defined(__APPLE__) || defined(__NetBSD__)
2783 struct sched_param sp;
2784 int policy;
2785 pthread_t self = pthread_self();
2786
2787 if (pthread_getschedparam(self, &policy, &sp) != 0)
2788 return OS_ERR;
2789
2790 sp.sched_priority = newpri;
2791 if (pthread_setschedparam(self, policy, &sp) != 0)
2792 return OS_ERR;
2793
2794 return OS_OK;
2795 #else
2796 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2797 return (ret == 0) ? OS_OK : OS_ERR;
2798 #endif
2799 }
2800
2801 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2802 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2803 *priority_ptr = java_to_os_priority[NormPriority];
2804 return OS_OK;
2805 }
2806
2807 errno = 0;
2808 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2809 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2810 #elif defined(__APPLE__) || defined(__NetBSD__)
2811 int policy;
2812 struct sched_param sp;
2813
2814 pthread_getschedparam(pthread_self(), &policy, &sp);
2815 *priority_ptr = sp.sched_priority;
2816 #else
2817 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2818 #endif
2819 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2820 }
2821
2822 // Hint to the underlying OS that a task switch would not be good.
2823 // Void return because it's a hint and can fail.
2824 void os::hint_no_preempt() {}
2825
2826 ////////////////////////////////////////////////////////////////////////////////
2827 // suspend/resume support
2828
2829 // the low-level signal-based suspend/resume support is a remnant from the
2830 // old VM-suspension that used to be for java-suspension, safepoints etc,
2831 // within hotspot. Now there is a single use-case for this:
2832 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2833 // that runs in the watcher thread.
2834 // The remaining code is greatly simplified from the more general suspension
2835 // code that used to be used.
2836 //
2837 // The protocol is quite simple:
2838 // - suspend:
2839 // - sends a signal to the target thread
2840 // - polls the suspend state of the osthread using a yield loop
2841 // - target thread signal handler (SR_handler) sets suspend state
2842 // and blocks in sigsuspend until continued
2843 // - resume:
2844 // - sets target osthread state to continue
2845 // - sends signal to end the sigsuspend loop in the SR_handler
2846 //
2847 // Note that the SR_lock plays no role in this suspend/resume protocol.
2848 //
2849
2850 static void resume_clear_context(OSThread *osthread) {
2851 osthread->set_ucontext(NULL);
2852 osthread->set_siginfo(NULL);
2853 }
2854
2855 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2856 osthread->set_ucontext(context);
2857 osthread->set_siginfo(siginfo);
2858 }
2859
2860 //
2861 // Handler function invoked when a thread's execution is suspended or
2862 // resumed. We have to be careful that only async-safe functions are
2863 // called here (Note: most pthread functions are not async safe and
2864 // should be avoided.)
2865 //
2866 // Note: sigwait() is a more natural fit than sigsuspend() from an
2867 // interface point of view, but sigwait() prevents the signal hander
2868 // from being run. libpthread would get very confused by not having
2869 // its signal handlers run and prevents sigwait()'s use with the
2870 // mutex granting granting signal.
2871 //
2872 // Currently only ever called on the VMThread or JavaThread
2873 //
2874 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2875 // Save and restore errno to avoid confusing native code with EINTR
2876 // after sigsuspend.
2877 int old_errno = errno;
2878
2879 Thread* thread = Thread::current();
2880 OSThread* osthread = thread->osthread();
2881 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2882
2883 os::SuspendResume::State current = osthread->sr.state();
2884 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2885 suspend_save_context(osthread, siginfo, context);
2886
2887 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2888 os::SuspendResume::State state = osthread->sr.suspended();
2889 if (state == os::SuspendResume::SR_SUSPENDED) {
2890 sigset_t suspend_set; // signals for sigsuspend()
2891
2892 // get current set of blocked signals and unblock resume signal
2893 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2894 sigdelset(&suspend_set, SR_signum);
2895
2896 sr_semaphore.signal();
2897 // wait here until we are resumed
2898 while (1) {
2899 sigsuspend(&suspend_set);
2900
2901 os::SuspendResume::State result = osthread->sr.running();
2902 if (result == os::SuspendResume::SR_RUNNING) {
2903 sr_semaphore.signal();
2904 break;
2905 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2906 ShouldNotReachHere();
2907 }
2908 }
2909
2910 } else if (state == os::SuspendResume::SR_RUNNING) {
2911 // request was cancelled, continue
2912 } else {
2913 ShouldNotReachHere();
2914 }
2915
2916 resume_clear_context(osthread);
2917 } else if (current == os::SuspendResume::SR_RUNNING) {
2918 // request was cancelled, continue
2919 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2920 // ignore
2921 } else {
2922 // ignore
2923 }
2924
2925 errno = old_errno;
2926 }
2927
2928
2929 static int SR_initialize() {
2930 struct sigaction act;
2931 char *s;
2932 /* Get signal number to use for suspend/resume */
2933 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2934 int sig = ::strtol(s, 0, 10);
2935 if (sig > 0 || sig < NSIG) {
2936 SR_signum = sig;
2937 }
2938 }
2939
2940 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2941 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2942
2943 sigemptyset(&SR_sigset);
2944 sigaddset(&SR_sigset, SR_signum);
2945
2946 /* Set up signal handler for suspend/resume */
2947 act.sa_flags = SA_RESTART|SA_SIGINFO;
2948 act.sa_handler = (void (*)(int)) SR_handler;
2949
2950 // SR_signum is blocked by default.
2951 // 4528190 - We also need to block pthread restart signal (32 on all
2952 // supported Bsd platforms). Note that BsdThreads need to block
2953 // this signal for all threads to work properly. So we don't have
2954 // to use hard-coded signal number when setting up the mask.
2955 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2956
2957 if (sigaction(SR_signum, &act, 0) == -1) {
2958 return -1;
2959 }
2960
2961 // Save signal flag
2962 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2963 return 0;
2964 }
2965
2966 static int sr_notify(OSThread* osthread) {
2967 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2968 assert_status(status == 0, status, "pthread_kill");
2969 return status;
2970 }
2971
2972 // "Randomly" selected value for how long we want to spin
2973 // before bailing out on suspending a thread, also how often
2974 // we send a signal to a thread we want to resume
2975 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2976 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2977
2978 // returns true on success and false on error - really an error is fatal
2979 // but this seems the normal response to library errors
2980 static bool do_suspend(OSThread* osthread) {
2981 assert(osthread->sr.is_running(), "thread should be running");
2982 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2983
2984 // mark as suspended and send signal
2985 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2986 // failed to switch, state wasn't running?
2987 ShouldNotReachHere();
2988 return false;
2989 }
2990
2991 if (sr_notify(osthread) != 0) {
2992 ShouldNotReachHere();
2993 }
2994
2995 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2996 while (true) {
2997 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2998 break;
2999 } else {
3000 // timeout
3001 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
3002 if (cancelled == os::SuspendResume::SR_RUNNING) {
3003 return false;
3004 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
3005 // make sure that we consume the signal on the semaphore as well
3006 sr_semaphore.wait();
3007 break;
3008 } else {
3009 ShouldNotReachHere();
3010 return false;
3011 }
3012 }
3013 }
3014
3015 guarantee(osthread->sr.is_suspended(), "Must be suspended");
3016 return true;
3017 }
3018
3019 static void do_resume(OSThread* osthread) {
3020 assert(osthread->sr.is_suspended(), "thread should be suspended");
3021 assert(!sr_semaphore.trywait(), "invalid semaphore state");
3022
3023 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
3024 // failed to switch to WAKEUP_REQUEST
3025 ShouldNotReachHere();
3026 return;
3027 }
3028
3029 while (true) {
3030 if (sr_notify(osthread) == 0) {
3031 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3032 if (osthread->sr.is_running()) {
3033 return;
3034 }
3035 }
3036 } else {
3037 ShouldNotReachHere();
3038 }
3039 }
3040
3041 guarantee(osthread->sr.is_running(), "Must be running!");
3042 }
3043
3044 ////////////////////////////////////////////////////////////////////////////////
3045 // interrupt support
3046
3047 void os::interrupt(Thread* thread) {
3048 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3049 "possibility of dangling Thread pointer");
3050
3051 OSThread* osthread = thread->osthread();
3052
3053 if (!osthread->interrupted()) {
3054 osthread->set_interrupted(true);
3055 // More than one thread can get here with the same value of osthread,
3056 // resulting in multiple notifications. We do, however, want the store
3057 // to interrupted() to be visible to other threads before we execute unpark().
3058 OrderAccess::fence();
3059 ParkEvent * const slp = thread->_SleepEvent ;
3060 if (slp != NULL) slp->unpark() ;
3061 }
3062
3063 // For JSR166. Unpark even if interrupt status already was set
3064 if (thread->is_Java_thread())
3065 ((JavaThread*)thread)->parker()->unpark();
3066
3067 ParkEvent * ev = thread->_ParkEvent ;
3068 if (ev != NULL) ev->unpark() ;
3069
3070 }
3071
3072 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3073 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3074 "possibility of dangling Thread pointer");
3075
3076 OSThread* osthread = thread->osthread();
3077
3078 bool interrupted = osthread->interrupted();
3079
3080 if (interrupted && clear_interrupted) {
3081 osthread->set_interrupted(false);
3082 // consider thread->_SleepEvent->reset() ... optional optimization
3083 }
3084
3085 return interrupted;
3086 }
3087
3088 ///////////////////////////////////////////////////////////////////////////////////
3089 // signal handling (except suspend/resume)
3090
3091 // This routine may be used by user applications as a "hook" to catch signals.
3092 // The user-defined signal handler must pass unrecognized signals to this
3093 // routine, and if it returns true (non-zero), then the signal handler must
3094 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3095 // routine will never retun false (zero), but instead will execute a VM panic
3096 // routine kill the process.
3097 //
3098 // If this routine returns false, it is OK to call it again. This allows
3099 // the user-defined signal handler to perform checks either before or after
3100 // the VM performs its own checks. Naturally, the user code would be making
3101 // a serious error if it tried to handle an exception (such as a null check
3102 // or breakpoint) that the VM was generating for its own correct operation.
3103 //
3104 // This routine may recognize any of the following kinds of signals:
3105 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3106 // It should be consulted by handlers for any of those signals.
3107 //
3108 // The caller of this routine must pass in the three arguments supplied
3109 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3110 // field of the structure passed to sigaction(). This routine assumes that
3111 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3112 //
3113 // Note that the VM will print warnings if it detects conflicting signal
3114 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3115 //
3116 extern "C" JNIEXPORT int
3117 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3118 void* ucontext, int abort_if_unrecognized);
3119
3120 void signalHandler(int sig, siginfo_t* info, void* uc) {
3121 assert(info != NULL && uc != NULL, "it must be old kernel");
3122 int orig_errno = errno; // Preserve errno value over signal handler.
3123 JVM_handle_bsd_signal(sig, info, uc, true);
3124 errno = orig_errno;
3125 }
3126
3127
3128 // This boolean allows users to forward their own non-matching signals
3129 // to JVM_handle_bsd_signal, harmlessly.
3130 bool os::Bsd::signal_handlers_are_installed = false;
3131
3132 // For signal-chaining
3133 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3134 unsigned int os::Bsd::sigs = 0;
3135 bool os::Bsd::libjsig_is_loaded = false;
3136 typedef struct sigaction *(*get_signal_t)(int);
3137 get_signal_t os::Bsd::get_signal_action = NULL;
3138
3139 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3140 struct sigaction *actp = NULL;
3141
3142 if (libjsig_is_loaded) {
3143 // Retrieve the old signal handler from libjsig
3144 actp = (*get_signal_action)(sig);
3145 }
3146 if (actp == NULL) {
3147 // Retrieve the preinstalled signal handler from jvm
3148 actp = get_preinstalled_handler(sig);
3149 }
3150
3151 return actp;
3152 }
3153
3154 static bool call_chained_handler(struct sigaction *actp, int sig,
3155 siginfo_t *siginfo, void *context) {
3156 // Call the old signal handler
3157 if (actp->sa_handler == SIG_DFL) {
3158 // It's more reasonable to let jvm treat it as an unexpected exception
3159 // instead of taking the default action.
3160 return false;
3161 } else if (actp->sa_handler != SIG_IGN) {
3162 if ((actp->sa_flags & SA_NODEFER) == 0) {
3163 // automaticlly block the signal
3164 sigaddset(&(actp->sa_mask), sig);
3165 }
3166
3167 sa_handler_t hand;
3168 sa_sigaction_t sa;
3169 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3170 // retrieve the chained handler
3171 if (siginfo_flag_set) {
3172 sa = actp->sa_sigaction;
3173 } else {
3174 hand = actp->sa_handler;
3175 }
3176
3177 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3178 actp->sa_handler = SIG_DFL;
3179 }
3180
3181 // try to honor the signal mask
3182 sigset_t oset;
3183 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3184
3185 // call into the chained handler
3186 if (siginfo_flag_set) {
3187 (*sa)(sig, siginfo, context);
3188 } else {
3189 (*hand)(sig);
3190 }
3191
3192 // restore the signal mask
3193 pthread_sigmask(SIG_SETMASK, &oset, 0);
3194 }
3195 // Tell jvm's signal handler the signal is taken care of.
3196 return true;
3197 }
3198
3199 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3200 bool chained = false;
3201 // signal-chaining
3202 if (UseSignalChaining) {
3203 struct sigaction *actp = get_chained_signal_action(sig);
3204 if (actp != NULL) {
3205 chained = call_chained_handler(actp, sig, siginfo, context);
3206 }
3207 }
3208 return chained;
3209 }
3210
3211 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3212 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3213 return &sigact[sig];
3214 }
3215 return NULL;
3216 }
3217
3218 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3219 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3220 sigact[sig] = oldAct;
3221 sigs |= (unsigned int)1 << sig;
3222 }
3223
3224 // for diagnostic
3225 int os::Bsd::sigflags[MAXSIGNUM];
3226
3227 int os::Bsd::get_our_sigflags(int sig) {
3228 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3229 return sigflags[sig];
3230 }
3231
3232 void os::Bsd::set_our_sigflags(int sig, int flags) {
3233 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3234 sigflags[sig] = flags;
3235 }
3236
3237 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3238 // Check for overwrite.
3239 struct sigaction oldAct;
3240 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3241
3242 void* oldhand = oldAct.sa_sigaction
3243 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3244 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3245 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3246 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3247 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3248 if (AllowUserSignalHandlers || !set_installed) {
3249 // Do not overwrite; user takes responsibility to forward to us.
3250 return;
3251 } else if (UseSignalChaining) {
3252 // save the old handler in jvm
3253 save_preinstalled_handler(sig, oldAct);
3254 // libjsig also interposes the sigaction() call below and saves the
3255 // old sigaction on it own.
3256 } else {
3257 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3258 "%#lx for signal %d.", (long)oldhand, sig));
3259 }
3260 }
3261
3262 struct sigaction sigAct;
3263 sigfillset(&(sigAct.sa_mask));
3264 sigAct.sa_handler = SIG_DFL;
3265 if (!set_installed) {
3266 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3267 } else {
3268 sigAct.sa_sigaction = signalHandler;
3269 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3270 }
3271 #ifdef __APPLE__
3272 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3273 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3274 // if the signal handler declares it will handle it on alternate stack.
3275 // Notice we only declare we will handle it on alt stack, but we are not
3276 // actually going to use real alt stack - this is just a workaround.
3277 // Please see ux_exception.c, method catch_mach_exception_raise for details
3278 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3279 if (sig == SIGSEGV) {
3280 sigAct.sa_flags |= SA_ONSTACK;
3281 }
3282 #endif
3283
3284 // Save flags, which are set by ours
3285 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3286 sigflags[sig] = sigAct.sa_flags;
3287
3288 int ret = sigaction(sig, &sigAct, &oldAct);
3289 assert(ret == 0, "check");
3290
3291 void* oldhand2 = oldAct.sa_sigaction
3292 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3293 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3294 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3295 }
3296
3297 // install signal handlers for signals that HotSpot needs to
3298 // handle in order to support Java-level exception handling.
3299
3300 void os::Bsd::install_signal_handlers() {
3301 if (!signal_handlers_are_installed) {
3302 signal_handlers_are_installed = true;
3303
3304 // signal-chaining
3305 typedef void (*signal_setting_t)();
3306 signal_setting_t begin_signal_setting = NULL;
3307 signal_setting_t end_signal_setting = NULL;
3308 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3309 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3310 if (begin_signal_setting != NULL) {
3311 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3312 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3313 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3314 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3315 libjsig_is_loaded = true;
3316 assert(UseSignalChaining, "should enable signal-chaining");
3317 }
3318 if (libjsig_is_loaded) {
3319 // Tell libjsig jvm is setting signal handlers
3320 (*begin_signal_setting)();
3321 }
3322
3323 set_signal_handler(SIGSEGV, true);
3324 set_signal_handler(SIGPIPE, true);
3325 set_signal_handler(SIGBUS, true);
3326 set_signal_handler(SIGILL, true);
3327 set_signal_handler(SIGFPE, true);
3328 set_signal_handler(SIGXFSZ, true);
3329
3330 #if defined(__APPLE__)
3331 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3332 // signals caught and handled by the JVM. To work around this, we reset the mach task
3333 // signal handler that's placed on our process by CrashReporter. This disables
3334 // CrashReporter-based reporting.
3335 //
3336 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3337 // on caught fatal signals.
3338 //
3339 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3340 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3341 // exception handling, while leaving the standard BSD signal handlers functional.
3342 kern_return_t kr;
3343 kr = task_set_exception_ports(mach_task_self(),
3344 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3345 MACH_PORT_NULL,
3346 EXCEPTION_STATE_IDENTITY,
3347 MACHINE_THREAD_STATE);
3348
3349 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3350 #endif
3351
3352 if (libjsig_is_loaded) {
3353 // Tell libjsig jvm finishes setting signal handlers
3354 (*end_signal_setting)();
3355 }
3356
3357 // We don't activate signal checker if libjsig is in place, we trust ourselves
3358 // and if UserSignalHandler is installed all bets are off
3359 if (CheckJNICalls) {
3360 if (libjsig_is_loaded) {
3361 if (PrintJNIResolving) {
3362 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3363 }
3364 check_signals = false;
3365 }
3366 if (AllowUserSignalHandlers) {
3367 if (PrintJNIResolving) {
3368 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3369 }
3370 check_signals = false;
3371 }
3372 }
3373 }
3374 }
3375
3376
3377 /////
3378 // glibc on Bsd platform uses non-documented flag
3379 // to indicate, that some special sort of signal
3380 // trampoline is used.
3381 // We will never set this flag, and we should
3382 // ignore this flag in our diagnostic
3383 #ifdef SIGNIFICANT_SIGNAL_MASK
3384 #undef SIGNIFICANT_SIGNAL_MASK
3385 #endif
3386 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3387
3388 static const char* get_signal_handler_name(address handler,
3389 char* buf, int buflen) {
3390 int offset;
3391 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3392 if (found) {
3393 // skip directory names
3394 const char *p1, *p2;
3395 p1 = buf;
3396 size_t len = strlen(os::file_separator());
3397 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3398 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3399 } else {
3400 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3401 }
3402 return buf;
3403 }
3404
3405 static void print_signal_handler(outputStream* st, int sig,
3406 char* buf, size_t buflen) {
3407 struct sigaction sa;
3408
3409 sigaction(sig, NULL, &sa);
3410
3411 // See comment for SIGNIFICANT_SIGNAL_MASK define
3412 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3413
3414 st->print("%s: ", os::exception_name(sig, buf, buflen));
3415
3416 address handler = (sa.sa_flags & SA_SIGINFO)
3417 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3418 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3419
3420 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3421 st->print("SIG_DFL");
3422 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3423 st->print("SIG_IGN");
3424 } else {
3425 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3426 }
3427
3428 st->print(", sa_mask[0]=");
3429 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3430
3431 address rh = VMError::get_resetted_sighandler(sig);
3432 // May be, handler was resetted by VMError?
3433 if(rh != NULL) {
3434 handler = rh;
3435 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3436 }
3437
3438 st->print(", sa_flags=");
3439 os::Posix::print_sa_flags(st, sa.sa_flags);
3440
3441 // Check: is it our handler?
3442 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3443 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3444 // It is our signal handler
3445 // check for flags, reset system-used one!
3446 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3447 st->print(
3448 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3449 os::Bsd::get_our_sigflags(sig));
3450 }
3451 }
3452 st->cr();
3453 }
3454
3455
3456 #define DO_SIGNAL_CHECK(sig) \
3457 if (!sigismember(&check_signal_done, sig)) \
3458 os::Bsd::check_signal_handler(sig)
3459
3460 // This method is a periodic task to check for misbehaving JNI applications
3461 // under CheckJNI, we can add any periodic checks here
3462
3463 void os::run_periodic_checks() {
3464
3465 if (check_signals == false) return;
3466
3467 // SEGV and BUS if overridden could potentially prevent
3468 // generation of hs*.log in the event of a crash, debugging
3469 // such a case can be very challenging, so we absolutely
3470 // check the following for a good measure:
3471 DO_SIGNAL_CHECK(SIGSEGV);
3472 DO_SIGNAL_CHECK(SIGILL);
3473 DO_SIGNAL_CHECK(SIGFPE);
3474 DO_SIGNAL_CHECK(SIGBUS);
3475 DO_SIGNAL_CHECK(SIGPIPE);
3476 DO_SIGNAL_CHECK(SIGXFSZ);
3477
3478
3479 // ReduceSignalUsage allows the user to override these handlers
3480 // see comments at the very top and jvm_solaris.h
3481 if (!ReduceSignalUsage) {
3482 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3483 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3484 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3485 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3486 }
3487
3488 DO_SIGNAL_CHECK(SR_signum);
3489 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3490 }
3491
3492 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3493
3494 static os_sigaction_t os_sigaction = NULL;
3495
3496 void os::Bsd::check_signal_handler(int sig) {
3497 char buf[O_BUFLEN];
3498 address jvmHandler = NULL;
3499
3500
3501 struct sigaction act;
3502 if (os_sigaction == NULL) {
3503 // only trust the default sigaction, in case it has been interposed
3504 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3505 if (os_sigaction == NULL) return;
3506 }
3507
3508 os_sigaction(sig, (struct sigaction*)NULL, &act);
3509
3510
3511 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3512
3513 address thisHandler = (act.sa_flags & SA_SIGINFO)
3514 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3515 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3516
3517
3518 switch(sig) {
3519 case SIGSEGV:
3520 case SIGBUS:
3521 case SIGFPE:
3522 case SIGPIPE:
3523 case SIGILL:
3524 case SIGXFSZ:
3525 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3526 break;
3527
3528 case SHUTDOWN1_SIGNAL:
3529 case SHUTDOWN2_SIGNAL:
3530 case SHUTDOWN3_SIGNAL:
3531 case BREAK_SIGNAL:
3532 jvmHandler = (address)user_handler();
3533 break;
3534
3535 case INTERRUPT_SIGNAL:
3536 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3537 break;
3538
3539 default:
3540 if (sig == SR_signum) {
3541 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3542 } else {
3543 return;
3544 }
3545 break;
3546 }
3547
3548 if (thisHandler != jvmHandler) {
3549 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3550 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3551 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3552 // No need to check this sig any longer
3553 sigaddset(&check_signal_done, sig);
3554 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3555 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3556 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3557 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3558 // No need to check this sig any longer
3559 sigaddset(&check_signal_done, sig);
3560 }
3561
3562 // Dump all the signal
3563 if (sigismember(&check_signal_done, sig)) {
3564 print_signal_handlers(tty, buf, O_BUFLEN);
3565 }
3566 }
3567
3568 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3569
3570 extern bool signal_name(int signo, char* buf, size_t len);
3571
3572 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3573 if (0 < exception_code && exception_code <= SIGRTMAX) {
3574 // signal
3575 if (!signal_name(exception_code, buf, size)) {
3576 jio_snprintf(buf, size, "SIG%d", exception_code);
3577 }
3578 return buf;
3579 } else {
3580 return NULL;
3581 }
3582 }
3583
3584 // this is called _before_ the most of global arguments have been parsed
3585 void os::init(void) {
3586 char dummy; /* used to get a guess on initial stack address */
3587 // first_hrtime = gethrtime();
3588
3589 // With BsdThreads the JavaMain thread pid (primordial thread)
3590 // is different than the pid of the java launcher thread.
3591 // So, on Bsd, the launcher thread pid is passed to the VM
3592 // via the sun.java.launcher.pid property.
3593 // Use this property instead of getpid() if it was correctly passed.
3594 // See bug 6351349.
3595 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3596
3597 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3598
3599 clock_tics_per_sec = CLK_TCK;
3600
3601 init_random(1234567);
3602
3603 ThreadCritical::initialize();
3604
3605 Bsd::set_page_size(getpagesize());
3606 if (Bsd::page_size() == -1) {
3607 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3608 strerror(errno)));
3609 }
3610 init_page_sizes((size_t) Bsd::page_size());
3611
3612 Bsd::initialize_system_info();
3613
3614 // main_thread points to the aboriginal thread
3615 Bsd::_main_thread = pthread_self();
3616
3617 Bsd::clock_init();
3618 initial_time_count = javaTimeNanos();
3619
3620 #ifdef __APPLE__
3621 // XXXDARWIN
3622 // Work around the unaligned VM callbacks in hotspot's
3623 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3624 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3625 // alignment when doing symbol lookup. To work around this, we force early
3626 // binding of all symbols now, thus binding when alignment is known-good.
3627 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3628 #endif
3629 }
3630
3631 // To install functions for atexit system call
3632 extern "C" {
3633 static void perfMemory_exit_helper() {
3634 perfMemory_exit();
3635 }
3636 }
3637
3638 // this is called _after_ the global arguments have been parsed
3639 jint os::init_2(void)
3640 {
3641 // Allocate a single page and mark it as readable for safepoint polling
3642 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3643 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3644
3645 os::set_polling_page( polling_page );
3646
3647 #ifndef PRODUCT
3648 if(Verbose && PrintMiscellaneous)
3649 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3650 #endif
3651
3652 if (!UseMembar) {
3653 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3654 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3655 os::set_memory_serialize_page( mem_serialize_page );
3656
3657 #ifndef PRODUCT
3658 if(Verbose && PrintMiscellaneous)
3659 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3660 #endif
3661 }
3662
3663 // initialize suspend/resume support - must do this before signal_sets_init()
3664 if (SR_initialize() != 0) {
3665 perror("SR_initialize failed");
3666 return JNI_ERR;
3667 }
3668
3669 Bsd::signal_sets_init();
3670 Bsd::install_signal_handlers();
3671
3672 // Check minimum allowable stack size for thread creation and to initialize
3673 // the java system classes, including StackOverflowError - depends on page
3674 // size. Add a page for compiler2 recursion in main thread.
3675 // Add in 2*BytesPerWord times page size to account for VM stack during
3676 // class initialization depending on 32 or 64 bit VM.
3677 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3678 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3679 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3680
3681 size_t threadStackSizeInBytes = ThreadStackSize * K;
3682 if (threadStackSizeInBytes != 0 &&
3683 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3684 tty->print_cr("\nThe stack size specified is too small, "
3685 "Specify at least %dk",
3686 os::Bsd::min_stack_allowed/ K);
3687 return JNI_ERR;
3688 }
3689
3690 // Make the stack size a multiple of the page size so that
3691 // the yellow/red zones can be guarded.
3692 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3693 vm_page_size()));
3694
3695 if (MaxFDLimit) {
3696 // set the number of file descriptors to max. print out error
3697 // if getrlimit/setrlimit fails but continue regardless.
3698 struct rlimit nbr_files;
3699 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3700 if (status != 0) {
3701 if (PrintMiscellaneous && (Verbose || WizardMode))
3702 perror("os::init_2 getrlimit failed");
3703 } else {
3704 nbr_files.rlim_cur = nbr_files.rlim_max;
3705
3706 #ifdef __APPLE__
3707 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3708 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3709 // be used instead
3710 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3711 #endif
3712
3713 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3714 if (status != 0) {
3715 if (PrintMiscellaneous && (Verbose || WizardMode))
3716 perror("os::init_2 setrlimit failed");
3717 }
3718 }
3719 }
3720
3721 // at-exit methods are called in the reverse order of their registration.
3722 // atexit functions are called on return from main or as a result of a
3723 // call to exit(3C). There can be only 32 of these functions registered
3724 // and atexit() does not set errno.
3725
3726 if (PerfAllowAtExitRegistration) {
3727 // only register atexit functions if PerfAllowAtExitRegistration is set.
3728 // atexit functions can be delayed until process exit time, which
3729 // can be problematic for embedded VM situations. Embedded VMs should
3730 // call DestroyJavaVM() to assure that VM resources are released.
3731
3732 // note: perfMemory_exit_helper atexit function may be removed in
3733 // the future if the appropriate cleanup code can be added to the
3734 // VM_Exit VMOperation's doit method.
3735 if (atexit(perfMemory_exit_helper) != 0) {
3736 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3737 }
3738 }
3739
3740 // initialize thread priority policy
3741 prio_init();
3742
3743 #ifdef __APPLE__
3744 // dynamically link to objective c gc registration
3745 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3746 if (handleLibObjc != NULL) {
3747 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3748 }
3749 #endif
3750
3751 return JNI_OK;
3752 }
3753
3754 // Mark the polling page as unreadable
3755 void os::make_polling_page_unreadable(void) {
3756 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3757 fatal("Could not disable polling page");
3758 };
3759
3760 // Mark the polling page as readable
3761 void os::make_polling_page_readable(void) {
3762 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3763 fatal("Could not enable polling page");
3764 }
3765 };
3766
3767 int os::active_processor_count() {
3768 return _processor_count;
3769 }
3770
3771 void os::set_native_thread_name(const char *name) {
3772 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3773 // This is only supported in Snow Leopard and beyond
3774 if (name != NULL) {
3775 // Add a "Java: " prefix to the name
3776 char buf[MAXTHREADNAMESIZE];
3777 snprintf(buf, sizeof(buf), "Java: %s", name);
3778 pthread_setname_np(buf);
3779 }
3780 #endif
3781 }
3782
3783 bool os::distribute_processes(uint length, uint* distribution) {
3784 // Not yet implemented.
3785 return false;
3786 }
3787
3788 bool os::bind_to_processor(uint processor_id) {
3789 // Not yet implemented.
3790 return false;
3791 }
3792
3793 void os::SuspendedThreadTask::internal_do_task() {
3794 if (do_suspend(_thread->osthread())) {
3795 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3796 do_task(context);
3797 do_resume(_thread->osthread());
3798 }
3799 }
3800
3801 ///
3802 class PcFetcher : public os::SuspendedThreadTask {
3803 public:
3804 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3805 ExtendedPC result();
3806 protected:
3807 void do_task(const os::SuspendedThreadTaskContext& context);
3808 private:
3809 ExtendedPC _epc;
3810 };
3811
3812 ExtendedPC PcFetcher::result() {
3813 guarantee(is_done(), "task is not done yet.");
3814 return _epc;
3815 }
3816
3817 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3818 Thread* thread = context.thread();
3819 OSThread* osthread = thread->osthread();
3820 if (osthread->ucontext() != NULL) {
3821 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3822 } else {
3823 // NULL context is unexpected, double-check this is the VMThread
3824 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3825 }
3826 }
3827
3828 // Suspends the target using the signal mechanism and then grabs the PC before
3829 // resuming the target. Used by the flat-profiler only
3830 ExtendedPC os::get_thread_pc(Thread* thread) {
3831 // Make sure that it is called by the watcher for the VMThread
3832 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3833 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3834
3835 PcFetcher fetcher(thread);
3836 fetcher.run();
3837 return fetcher.result();
3838 }
3839
3840 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3841 {
3842 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3843 }
3844
3845 ////////////////////////////////////////////////////////////////////////////////
3846 // debug support
3847
3848 bool os::find(address addr, outputStream* st) {
3849 Dl_info dlinfo;
3850 memset(&dlinfo, 0, sizeof(dlinfo));
3851 if (dladdr(addr, &dlinfo) != 0) {
3852 st->print(PTR_FORMAT ": ", addr);
3853 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3854 st->print("%s+%#x", dlinfo.dli_sname,
3855 addr - (intptr_t)dlinfo.dli_saddr);
3856 } else if (dlinfo.dli_fbase != NULL) {
3857 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3858 } else {
3859 st->print("<absolute address>");
3860 }
3861 if (dlinfo.dli_fname != NULL) {
3862 st->print(" in %s", dlinfo.dli_fname);
3863 }
3864 if (dlinfo.dli_fbase != NULL) {
3865 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3866 }
3867 st->cr();
3868
3869 if (Verbose) {
3870 // decode some bytes around the PC
3871 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3872 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3873 address lowest = (address) dlinfo.dli_sname;
3874 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3875 if (begin < lowest) begin = lowest;
3876 Dl_info dlinfo2;
3877 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3878 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3879 end = (address) dlinfo2.dli_saddr;
3880 Disassembler::decode(begin, end, st);
3881 }
3882 return true;
3883 }
3884 return false;
3885 }
3886
3887 ////////////////////////////////////////////////////////////////////////////////
3888 // misc
3889
3890 // This does not do anything on Bsd. This is basically a hook for being
3891 // able to use structured exception handling (thread-local exception filters)
3892 // on, e.g., Win32.
3893 void
3894 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3895 JavaCallArguments* args, Thread* thread) {
3896 f(value, method, args, thread);
3897 }
3898
3899 void os::print_statistics() {
3900 }
3901
3902 int os::message_box(const char* title, const char* message) {
3903 int i;
3904 fdStream err(defaultStream::error_fd());
3905 for (i = 0; i < 78; i++) err.print_raw("=");
3906 err.cr();
3907 err.print_raw_cr(title);
3908 for (i = 0; i < 78; i++) err.print_raw("-");
3909 err.cr();
3910 err.print_raw_cr(message);
3911 for (i = 0; i < 78; i++) err.print_raw("=");
3912 err.cr();
3913
3914 char buf[16];
3915 // Prevent process from exiting upon "read error" without consuming all CPU
3916 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3917
3918 return buf[0] == 'y' || buf[0] == 'Y';
3919 }
3920
3921 int os::stat(const char *path, struct stat *sbuf) {
3922 char pathbuf[MAX_PATH];
3923 if (strlen(path) > MAX_PATH - 1) {
3924 errno = ENAMETOOLONG;
3925 return -1;
3926 }
3927 os::native_path(strcpy(pathbuf, path));
3928 return ::stat(pathbuf, sbuf);
3929 }
3930
3931 bool os::check_heap(bool force) {
3932 return true;
3933 }
3934
3935 ATTRIBUTE_PRINTF(3, 0)
3936 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3937 return ::vsnprintf(buf, count, format, args);
3938 }
3939
3940 // Is a (classpath) directory empty?
3941 bool os::dir_is_empty(const char* path) {
3942 DIR *dir = NULL;
3943 struct dirent *ptr;
3944
3945 dir = opendir(path);
3946 if (dir == NULL) return true;
3947
3948 /* Scan the directory */
3949 bool result = true;
3950 char buf[sizeof(struct dirent) + MAX_PATH];
3951 while (result && (ptr = ::readdir(dir)) != NULL) {
3952 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3953 result = false;
3954 }
3955 }
3956 closedir(dir);
3957 return result;
3958 }
3959
3960 // This code originates from JDK's sysOpen and open64_w
3961 // from src/solaris/hpi/src/system_md.c
3962
3963 #ifndef O_DELETE
3964 #define O_DELETE 0x10000
3965 #endif
3966
3967 // Open a file. Unlink the file immediately after open returns
3968 // if the specified oflag has the O_DELETE flag set.
3969 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3970
3971 int os::open(const char *path, int oflag, int mode) {
3972
3973 if (strlen(path) > MAX_PATH - 1) {
3974 errno = ENAMETOOLONG;
3975 return -1;
3976 }
3977 int fd;
3978 int o_delete = (oflag & O_DELETE);
3979 oflag = oflag & ~O_DELETE;
3980
3981 fd = ::open(path, oflag, mode);
3982 if (fd == -1) return -1;
3983
3984 //If the open succeeded, the file might still be a directory
3985 {
3986 struct stat buf;
3987 int ret = ::fstat(fd, &buf);
3988 int st_mode = buf.st_mode;
3989
3990 if (ret != -1) {
3991 if ((st_mode & S_IFMT) == S_IFDIR) {
3992 errno = EISDIR;
3993 ::close(fd);
3994 return -1;
3995 }
3996 } else {
3997 ::close(fd);
3998 return -1;
3999 }
4000 }
4001
4002 /*
4003 * All file descriptors that are opened in the JVM and not
4004 * specifically destined for a subprocess should have the
4005 * close-on-exec flag set. If we don't set it, then careless 3rd
4006 * party native code might fork and exec without closing all
4007 * appropriate file descriptors (e.g. as we do in closeDescriptors in
4008 * UNIXProcess.c), and this in turn might:
4009 *
4010 * - cause end-of-file to fail to be detected on some file
4011 * descriptors, resulting in mysterious hangs, or
4012 *
4013 * - might cause an fopen in the subprocess to fail on a system
4014 * suffering from bug 1085341.
4015 *
4016 * (Yes, the default setting of the close-on-exec flag is a Unix
4017 * design flaw)
4018 *
4019 * See:
4020 * 1085341: 32-bit stdio routines should support file descriptors >255
4021 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4022 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4023 */
4024 #ifdef FD_CLOEXEC
4025 {
4026 int flags = ::fcntl(fd, F_GETFD);
4027 if (flags != -1)
4028 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4029 }
4030 #endif
4031
4032 if (o_delete != 0) {
4033 ::unlink(path);
4034 }
4035 return fd;
4036 }
4037
4038
4039 // create binary file, rewriting existing file if required
4040 int os::create_binary_file(const char* path, bool rewrite_existing) {
4041 int oflags = O_WRONLY | O_CREAT;
4042 if (!rewrite_existing) {
4043 oflags |= O_EXCL;
4044 }
4045 return ::open(path, oflags, S_IREAD | S_IWRITE);
4046 }
4047
4048 // return current position of file pointer
4049 jlong os::current_file_offset(int fd) {
4050 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4051 }
4052
4053 // move file pointer to the specified offset
4054 jlong os::seek_to_file_offset(int fd, jlong offset) {
4055 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4056 }
4057
4058 // This code originates from JDK's sysAvailable
4059 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4060
4061 int os::available(int fd, jlong *bytes) {
4062 jlong cur, end;
4063 int mode;
4064 struct stat buf;
4065
4066 if (::fstat(fd, &buf) >= 0) {
4067 mode = buf.st_mode;
4068 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4069 /*
4070 * XXX: is the following call interruptible? If so, this might
4071 * need to go through the INTERRUPT_IO() wrapper as for other
4072 * blocking, interruptible calls in this file.
4073 */
4074 int n;
4075 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4076 *bytes = n;
4077 return 1;
4078 }
4079 }
4080 }
4081 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4082 return 0;
4083 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4084 return 0;
4085 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4086 return 0;
4087 }
4088 *bytes = end - cur;
4089 return 1;
4090 }
4091
4092 int os::socket_available(int fd, jint *pbytes) {
4093 if (fd < 0)
4094 return OS_OK;
4095
4096 int ret;
4097
4098 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4099
4100 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4101 // is expected to return 0 on failure and 1 on success to the jdk.
4102
4103 return (ret == OS_ERR) ? 0 : 1;
4104 }
4105
4106 // Map a block of memory.
4107 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4108 char *addr, size_t bytes, bool read_only,
4109 bool allow_exec) {
4110 int prot;
4111 int flags;
4112
4113 if (read_only) {
4114 prot = PROT_READ;
4115 flags = MAP_SHARED;
4116 } else {
4117 prot = PROT_READ | PROT_WRITE;
4118 flags = MAP_PRIVATE;
4119 }
4120
4121 if (allow_exec) {
4122 prot |= PROT_EXEC;
4123 }
4124
4125 if (addr != NULL) {
4126 flags |= MAP_FIXED;
4127 }
4128
4129 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4130 fd, file_offset);
4131 if (mapped_address == MAP_FAILED) {
4132 return NULL;
4133 }
4134 return mapped_address;
4135 }
4136
4137
4138 // Remap a block of memory.
4139 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4140 char *addr, size_t bytes, bool read_only,
4141 bool allow_exec) {
4142 // same as map_memory() on this OS
4143 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4144 allow_exec);
4145 }
4146
4147
4148 // Unmap a block of memory.
4149 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4150 return munmap(addr, bytes) == 0;
4151 }
4152
4153 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4154 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4155 // of a thread.
4156 //
4157 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4158 // the fast estimate available on the platform.
4159
4160 jlong os::current_thread_cpu_time() {
4161 #ifdef __APPLE__
4162 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4163 #else
4164 Unimplemented();
4165 return 0;
4166 #endif
4167 }
4168
4169 jlong os::thread_cpu_time(Thread* thread) {
4170 #ifdef __APPLE__
4171 return os::thread_cpu_time(thread, true /* user + sys */);
4172 #else
4173 Unimplemented();
4174 return 0;
4175 #endif
4176 }
4177
4178 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4179 #ifdef __APPLE__
4180 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4181 #else
4182 Unimplemented();
4183 return 0;
4184 #endif
4185 }
4186
4187 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4188 #ifdef __APPLE__
4189 struct thread_basic_info tinfo;
4190 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4191 kern_return_t kr;
4192 thread_t mach_thread;
4193
4194 mach_thread = thread->osthread()->thread_id();
4195 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4196 if (kr != KERN_SUCCESS)
4197 return -1;
4198
4199 if (user_sys_cpu_time) {
4200 jlong nanos;
4201 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4202 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4203 return nanos;
4204 } else {
4205 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4206 }
4207 #else
4208 Unimplemented();
4209 return 0;
4210 #endif
4211 }
4212
4213
4214 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4215 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4216 info_ptr->may_skip_backward = false; // elapsed time not wall time
4217 info_ptr->may_skip_forward = false; // elapsed time not wall time
4218 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4219 }
4220
4221 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4222 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4223 info_ptr->may_skip_backward = false; // elapsed time not wall time
4224 info_ptr->may_skip_forward = false; // elapsed time not wall time
4225 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4226 }
4227
4228 bool os::is_thread_cpu_time_supported() {
4229 #ifdef __APPLE__
4230 return true;
4231 #else
4232 return false;
4233 #endif
4234 }
4235
4236 // System loadavg support. Returns -1 if load average cannot be obtained.
4237 // Bsd doesn't yet have a (official) notion of processor sets,
4238 // so just return the system wide load average.
4239 int os::loadavg(double loadavg[], int nelem) {
4240 return ::getloadavg(loadavg, nelem);
4241 }
4242
4243 void os::pause() {
4244 char filename[MAX_PATH];
4245 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4246 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4247 } else {
4248 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4249 }
4250
4251 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4252 if (fd != -1) {
4253 struct stat buf;
4254 ::close(fd);
4255 while (::stat(filename, &buf) == 0) {
4256 (void)::poll(NULL, 0, 100);
4257 }
4258 } else {
4259 jio_fprintf(stderr,
4260 "Could not open pause file '%s', continuing immediately.\n", filename);
4261 }
4262 }
4263
4264
4265 // Refer to the comments in os_solaris.cpp park-unpark.
4266 //
4267 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4268 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4269 // For specifics regarding the bug see GLIBC BUGID 261237 :
4270 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4271 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4272 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4273 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4274 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4275 // and monitorenter when we're using 1-0 locking. All those operations may result in
4276 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4277 // of libpthread avoids the problem, but isn't practical.
4278 //
4279 // Possible remedies:
4280 //
4281 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4282 // This is palliative and probabilistic, however. If the thread is preempted
4283 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4284 // than the minimum period may have passed, and the abstime may be stale (in the
4285 // past) resultin in a hang. Using this technique reduces the odds of a hang
4286 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4287 //
4288 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4289 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4290 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4291 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4292 // thread.
4293 //
4294 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4295 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4296 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4297 // This also works well. In fact it avoids kernel-level scalability impediments
4298 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4299 // timers in a graceful fashion.
4300 //
4301 // 4. When the abstime value is in the past it appears that control returns
4302 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4303 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4304 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4305 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4306 // It may be possible to avoid reinitialization by checking the return
4307 // value from pthread_cond_timedwait(). In addition to reinitializing the
4308 // condvar we must establish the invariant that cond_signal() is only called
4309 // within critical sections protected by the adjunct mutex. This prevents
4310 // cond_signal() from "seeing" a condvar that's in the midst of being
4311 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4312 // desirable signal-after-unlock optimization that avoids futile context switching.
4313 //
4314 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4315 // structure when a condvar is used or initialized. cond_destroy() would
4316 // release the helper structure. Our reinitialize-after-timedwait fix
4317 // put excessive stress on malloc/free and locks protecting the c-heap.
4318 //
4319 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4320 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4321 // and only enabling the work-around for vulnerable environments.
4322
4323 // utility to compute the abstime argument to timedwait:
4324 // millis is the relative timeout time
4325 // abstime will be the absolute timeout time
4326 // TODO: replace compute_abstime() with unpackTime()
4327
4328 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4329 if (millis < 0) millis = 0;
4330 struct timeval now;
4331 int status = gettimeofday(&now, NULL);
4332 assert(status == 0, "gettimeofday");
4333 jlong seconds = millis / 1000;
4334 millis %= 1000;
4335 if (seconds > 50000000) { // see man cond_timedwait(3T)
4336 seconds = 50000000;
4337 }
4338 abstime->tv_sec = now.tv_sec + seconds;
4339 long usec = now.tv_usec + millis * 1000;
4340 if (usec >= 1000000) {
4341 abstime->tv_sec += 1;
4342 usec -= 1000000;
4343 }
4344 abstime->tv_nsec = usec * 1000;
4345 return abstime;
4346 }
4347
4348
4349 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4350 // Conceptually TryPark() should be equivalent to park(0).
4351
4352 int os::PlatformEvent::TryPark() {
4353 for (;;) {
4354 const int v = _Event ;
4355 guarantee ((v == 0) || (v == 1), "invariant") ;
4356 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4357 }
4358 }
4359
4360 void os::PlatformEvent::park() { // AKA "down()"
4361 // Invariant: Only the thread associated with the Event/PlatformEvent
4362 // may call park().
4363 // TODO: assert that _Assoc != NULL or _Assoc == Self
4364 int v ;
4365 for (;;) {
4366 v = _Event ;
4367 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4368 }
4369 guarantee (v >= 0, "invariant") ;
4370 if (v == 0) {
4371 // Do this the hard way by blocking ...
4372 int status = pthread_mutex_lock(_mutex);
4373 assert_status(status == 0, status, "mutex_lock");
4374 guarantee (_nParked == 0, "invariant") ;
4375 ++ _nParked ;
4376 while (_Event < 0) {
4377 status = pthread_cond_wait(_cond, _mutex);
4378 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4379 // Treat this the same as if the wait was interrupted
4380 if (status == ETIMEDOUT) { status = EINTR; }
4381 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4382 }
4383 -- _nParked ;
4384
4385 _Event = 0 ;
4386 status = pthread_mutex_unlock(_mutex);
4387 assert_status(status == 0, status, "mutex_unlock");
4388 // Paranoia to ensure our locked and lock-free paths interact
4389 // correctly with each other.
4390 OrderAccess::fence();
4391 }
4392 guarantee (_Event >= 0, "invariant") ;
4393 }
4394
4395 int os::PlatformEvent::park(jlong millis) {
4396 guarantee (_nParked == 0, "invariant") ;
4397
4398 int v ;
4399 for (;;) {
4400 v = _Event ;
4401 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4402 }
4403 guarantee (v >= 0, "invariant") ;
4404 if (v != 0) return OS_OK ;
4405
4406 // We do this the hard way, by blocking the thread.
4407 // Consider enforcing a minimum timeout value.
4408 struct timespec abst;
4409 compute_abstime(&abst, millis);
4410
4411 int ret = OS_TIMEOUT;
4412 int status = pthread_mutex_lock(_mutex);
4413 assert_status(status == 0, status, "mutex_lock");
4414 guarantee (_nParked == 0, "invariant") ;
4415 ++_nParked ;
4416
4417 // Object.wait(timo) will return because of
4418 // (a) notification
4419 // (b) timeout
4420 // (c) thread.interrupt
4421 //
4422 // Thread.interrupt and object.notify{All} both call Event::set.
4423 // That is, we treat thread.interrupt as a special case of notification.
4424 // The underlying Solaris implementation, cond_timedwait, admits
4425 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4426 // JVM from making those visible to Java code. As such, we must
4427 // filter out spurious wakeups. We assume all ETIME returns are valid.
4428 //
4429 // TODO: properly differentiate simultaneous notify+interrupt.
4430 // In that case, we should propagate the notify to another waiter.
4431
4432 while (_Event < 0) {
4433 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4434 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4435 pthread_cond_destroy (_cond);
4436 pthread_cond_init (_cond, NULL) ;
4437 }
4438 assert_status(status == 0 || status == EINTR ||
4439 status == ETIMEDOUT,
4440 status, "cond_timedwait");
4441 if (!FilterSpuriousWakeups) break ; // previous semantics
4442 if (status == ETIMEDOUT) break ;
4443 // We consume and ignore EINTR and spurious wakeups.
4444 }
4445 --_nParked ;
4446 if (_Event >= 0) {
4447 ret = OS_OK;
4448 }
4449 _Event = 0 ;
4450 status = pthread_mutex_unlock(_mutex);
4451 assert_status(status == 0, status, "mutex_unlock");
4452 assert (_nParked == 0, "invariant") ;
4453 // Paranoia to ensure our locked and lock-free paths interact
4454 // correctly with each other.
4455 OrderAccess::fence();
4456 return ret;
4457 }
4458
4459 void os::PlatformEvent::unpark() {
4460 // Transitions for _Event:
4461 // 0 :=> 1
4462 // 1 :=> 1
4463 // -1 :=> either 0 or 1; must signal target thread
4464 // That is, we can safely transition _Event from -1 to either
4465 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4466 // unpark() calls.
4467 // See also: "Semaphores in Plan 9" by Mullender & Cox
4468 //
4469 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4470 // that it will take two back-to-back park() calls for the owning
4471 // thread to block. This has the benefit of forcing a spurious return
4472 // from the first park() call after an unpark() call which will help
4473 // shake out uses of park() and unpark() without condition variables.
4474
4475 if (Atomic::xchg(1, &_Event) >= 0) return;
4476
4477 // Wait for the thread associated with the event to vacate
4478 int status = pthread_mutex_lock(_mutex);
4479 assert_status(status == 0, status, "mutex_lock");
4480 int AnyWaiters = _nParked;
4481 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4482 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4483 AnyWaiters = 0;
4484 pthread_cond_signal(_cond);
4485 }
4486 status = pthread_mutex_unlock(_mutex);
4487 assert_status(status == 0, status, "mutex_unlock");
4488 if (AnyWaiters != 0) {
4489 status = pthread_cond_signal(_cond);
4490 assert_status(status == 0, status, "cond_signal");
4491 }
4492
4493 // Note that we signal() _after dropping the lock for "immortal" Events.
4494 // This is safe and avoids a common class of futile wakeups. In rare
4495 // circumstances this can cause a thread to return prematurely from
4496 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4497 // simply re-test the condition and re-park itself.
4498 }
4499
4500
4501 // JSR166
4502 // -------------------------------------------------------
4503
4504 /*
4505 * The solaris and bsd implementations of park/unpark are fairly
4506 * conservative for now, but can be improved. They currently use a
4507 * mutex/condvar pair, plus a a count.
4508 * Park decrements count if > 0, else does a condvar wait. Unpark
4509 * sets count to 1 and signals condvar. Only one thread ever waits
4510 * on the condvar. Contention seen when trying to park implies that someone
4511 * is unparking you, so don't wait. And spurious returns are fine, so there
4512 * is no need to track notifications.
4513 */
4514
4515 #define MAX_SECS 100000000
4516 /*
4517 * This code is common to bsd and solaris and will be moved to a
4518 * common place in dolphin.
4519 *
4520 * The passed in time value is either a relative time in nanoseconds
4521 * or an absolute time in milliseconds. Either way it has to be unpacked
4522 * into suitable seconds and nanoseconds components and stored in the
4523 * given timespec structure.
4524 * Given time is a 64-bit value and the time_t used in the timespec is only
4525 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4526 * overflow if times way in the future are given. Further on Solaris versions
4527 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4528 * number of seconds, in abstime, is less than current_time + 100,000,000.
4529 * As it will be 28 years before "now + 100000000" will overflow we can
4530 * ignore overflow and just impose a hard-limit on seconds using the value
4531 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4532 * years from "now".
4533 */
4534
4535 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4536 assert (time > 0, "convertTime");
4537
4538 struct timeval now;
4539 int status = gettimeofday(&now, NULL);
4540 assert(status == 0, "gettimeofday");
4541
4542 time_t max_secs = now.tv_sec + MAX_SECS;
4543
4544 if (isAbsolute) {
4545 jlong secs = time / 1000;
4546 if (secs > max_secs) {
4547 absTime->tv_sec = max_secs;
4548 }
4549 else {
4550 absTime->tv_sec = secs;
4551 }
4552 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4553 }
4554 else {
4555 jlong secs = time / NANOSECS_PER_SEC;
4556 if (secs >= MAX_SECS) {
4557 absTime->tv_sec = max_secs;
4558 absTime->tv_nsec = 0;
4559 }
4560 else {
4561 absTime->tv_sec = now.tv_sec + secs;
4562 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4563 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4564 absTime->tv_nsec -= NANOSECS_PER_SEC;
4565 ++absTime->tv_sec; // note: this must be <= max_secs
4566 }
4567 }
4568 }
4569 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4570 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4571 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4572 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4573 }
4574
4575 void Parker::park(bool isAbsolute, jlong time) {
4576 // Ideally we'd do something useful while spinning, such
4577 // as calling unpackTime().
4578
4579 // Optional fast-path check:
4580 // Return immediately if a permit is available.
4581 // We depend on Atomic::xchg() having full barrier semantics
4582 // since we are doing a lock-free update to _counter.
4583 if (Atomic::xchg(0, &_counter) > 0) return;
4584
4585 Thread* thread = Thread::current();
4586 assert(thread->is_Java_thread(), "Must be JavaThread");
4587 JavaThread *jt = (JavaThread *)thread;
4588
4589 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4590 // Check interrupt before trying to wait
4591 if (Thread::is_interrupted(thread, false)) {
4592 return;
4593 }
4594
4595 // Next, demultiplex/decode time arguments
4596 struct timespec absTime;
4597 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4598 return;
4599 }
4600 if (time > 0) {
4601 unpackTime(&absTime, isAbsolute, time);
4602 }
4603
4604
4605 // Enter safepoint region
4606 // Beware of deadlocks such as 6317397.
4607 // The per-thread Parker:: mutex is a classic leaf-lock.
4608 // In particular a thread must never block on the Threads_lock while
4609 // holding the Parker:: mutex. If safepoints are pending both the
4610 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4611 ThreadBlockInVM tbivm(jt);
4612
4613 // Don't wait if cannot get lock since interference arises from
4614 // unblocking. Also. check interrupt before trying wait
4615 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4616 return;
4617 }
4618
4619 int status ;
4620 if (_counter > 0) { // no wait needed
4621 _counter = 0;
4622 status = pthread_mutex_unlock(_mutex);
4623 assert (status == 0, "invariant") ;
4624 // Paranoia to ensure our locked and lock-free paths interact
4625 // correctly with each other and Java-level accesses.
4626 OrderAccess::fence();
4627 return;
4628 }
4629
4630 #ifdef ASSERT
4631 // Don't catch signals while blocked; let the running threads have the signals.
4632 // (This allows a debugger to break into the running thread.)
4633 sigset_t oldsigs;
4634 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4635 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4636 #endif
4637
4638 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4639 jt->set_suspend_equivalent();
4640 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4641
4642 if (time == 0) {
4643 status = pthread_cond_wait (_cond, _mutex) ;
4644 } else {
4645 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4646 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4647 pthread_cond_destroy (_cond) ;
4648 pthread_cond_init (_cond, NULL);
4649 }
4650 }
4651 assert_status(status == 0 || status == EINTR ||
4652 status == ETIMEDOUT,
4653 status, "cond_timedwait");
4654
4655 #ifdef ASSERT
4656 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4657 #endif
4658
4659 _counter = 0 ;
4660 status = pthread_mutex_unlock(_mutex) ;
4661 assert_status(status == 0, status, "invariant") ;
4662 // Paranoia to ensure our locked and lock-free paths interact
4663 // correctly with each other and Java-level accesses.
4664 OrderAccess::fence();
4665
4666 // If externally suspended while waiting, re-suspend
4667 if (jt->handle_special_suspend_equivalent_condition()) {
4668 jt->java_suspend_self();
4669 }
4670 }
4671
4672 void Parker::unpark() {
4673 int s, status ;
4674 status = pthread_mutex_lock(_mutex);
4675 assert (status == 0, "invariant") ;
4676 s = _counter;
4677 _counter = 1;
4678 if (s < 1) {
4679 if (WorkAroundNPTLTimedWaitHang) {
4680 status = pthread_cond_signal (_cond) ;
4681 assert (status == 0, "invariant") ;
4682 status = pthread_mutex_unlock(_mutex);
4683 assert (status == 0, "invariant") ;
4684 } else {
4685 status = pthread_mutex_unlock(_mutex);
4686 assert (status == 0, "invariant") ;
4687 status = pthread_cond_signal (_cond) ;
4688 assert (status == 0, "invariant") ;
4689 }
4690 } else {
4691 pthread_mutex_unlock(_mutex);
4692 assert (status == 0, "invariant") ;
4693 }
4694 }
4695
4696
4697 /* Darwin has no "environ" in a dynamic library. */
4698 #ifdef __APPLE__
4699 #include <crt_externs.h>
4700 #define environ (*_NSGetEnviron())
4701 #else
4702 extern char** environ;
4703 #endif
4704
4705 // Run the specified command in a separate process. Return its exit value,
4706 // or -1 on failure (e.g. can't fork a new process).
4707 // Unlike system(), this function can be called from signal handler. It
4708 // doesn't block SIGINT et al.
4709 int os::fork_and_exec(char* cmd) {
4710 const char * argv[4] = {"sh", "-c", cmd, NULL};
4711
4712 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4713 // pthread_atfork handlers and reset pthread library. All we need is a
4714 // separate process to execve. Make a direct syscall to fork process.
4715 // On IA64 there's no fork syscall, we have to use fork() and hope for
4716 // the best...
4717 pid_t pid = fork();
4718
4719 if (pid < 0) {
4720 // fork failed
4721 return -1;
4722
4723 } else if (pid == 0) {
4724 // child process
4725
4726 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4727 // first to kill every thread on the thread list. Because this list is
4728 // not reset by fork() (see notes above), execve() will instead kill
4729 // every thread in the parent process. We know this is the only thread
4730 // in the new process, so make a system call directly.
4731 // IA64 should use normal execve() from glibc to match the glibc fork()
4732 // above.
4733 execve("/bin/sh", (char* const*)argv, environ);
4734
4735 // execve failed
4736 _exit(-1);
4737
4738 } else {
4739 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4740 // care about the actual exit code, for now.
4741
4742 int status;
4743
4744 // Wait for the child process to exit. This returns immediately if
4745 // the child has already exited. */
4746 while (waitpid(pid, &status, 0) < 0) {
4747 switch (errno) {
4748 case ECHILD: return 0;
4749 case EINTR: break;
4750 default: return -1;
4751 }
4752 }
4753
4754 if (WIFEXITED(status)) {
4755 // The child exited normally; get its exit code.
4756 return WEXITSTATUS(status);
4757 } else if (WIFSIGNALED(status)) {
4758 // The child exited because of a signal
4759 // The best value to return is 0x80 + signal number,
4760 // because that is what all Unix shells do, and because
4761 // it allows callers to distinguish between process exit and
4762 // process death by signal.
4763 return 0x80 + WTERMSIG(status);
4764 } else {
4765 // Unknown exit code; pass it through
4766 return status;
4767 }
4768 }
4769 }
4770
4771 // is_headless_jre()
4772 //
4773 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4774 // in order to report if we are running in a headless jre
4775 //
4776 // Since JDK8 xawt/libmawt.so was moved into the same directory
4777 // as libawt.so, and renamed libawt_xawt.so
4778 //
4779 bool os::is_headless_jre() {
4780 #ifdef __APPLE__
4781 // We no longer build headless-only on Mac OS X
4782 return false;
4783 #else
4784 struct stat statbuf;
4785 char buf[MAXPATHLEN];
4786 char libmawtpath[MAXPATHLEN];
4787 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4788 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4789 char *p;
4790
4791 // Get path to libjvm.so
4792 os::jvm_path(buf, sizeof(buf));
4793
4794 // Get rid of libjvm.so
4795 p = strrchr(buf, '/');
4796 if (p == NULL) return false;
4797 else *p = '\0';
4798
4799 // Get rid of client or server
4800 p = strrchr(buf, '/');
4801 if (p == NULL) return false;
4802 else *p = '\0';
4803
4804 // check xawt/libmawt.so
4805 strcpy(libmawtpath, buf);
4806 strcat(libmawtpath, xawtstr);
4807 if (::stat(libmawtpath, &statbuf) == 0) return false;
4808
4809 // check libawt_xawt.so
4810 strcpy(libmawtpath, buf);
4811 strcat(libmawtpath, new_xawtstr);
4812 if (::stat(libmawtpath, &statbuf) == 0) return false;
4813
4814 return true;
4815 #endif
4816 }
4817
4818 // Get the default path to the core file
4819 // Returns the length of the string
4820 int os::get_core_path(char* buffer, size_t bufferSize) {
4821 int n = jio_snprintf(buffer, bufferSize, "/cores");
4822
4823 // Truncate if theoretical string was longer than bufferSize
4824 n = MIN2(n, (int)bufferSize);
4825
4826 return n;
4827 }
4828
4829 #ifndef PRODUCT
4830 void TestReserveMemorySpecial_test() {
4831 // No tests available for this platform
4832 }
4833 #endif