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 #elif __FreeBSD__
1201 retval = syscall(SYS_thr_self);
1202 #elif __OpenBSD__
1203 retval = syscall(SYS_getthrid);
1204 #elif __NetBSD__
1205 retval = (pid_t) syscall(SYS__lwp_self);
1206 #endif
1207
1208 if (retval == -1) {
1209 return getpid();
1210 }
1211 }
1212
1213 intx os::current_thread_id() {
1214 #ifdef __APPLE__
1215 return (intx)::pthread_mach_thread_np(::pthread_self());
1216 #else
1217 return (intx)::pthread_self();
1218 #endif
1219 }
1220
1221 int os::current_process_id() {
1222
1223 // Under the old bsd thread library, bsd gives each thread
1224 // its own process id. Because of this each thread will return
1225 // a different pid if this method were to return the result
1226 // of getpid(2). Bsd provides no api that returns the pid
1227 // of the launcher thread for the vm. This implementation
1228 // returns a unique pid, the pid of the launcher thread
1229 // that starts the vm 'process'.
1230
1231 // Under the NPTL, getpid() returns the same pid as the
1232 // launcher thread rather than a unique pid per thread.
1233 // Use gettid() if you want the old pre NPTL behaviour.
1234
1235 // if you are looking for the result of a call to getpid() that
1236 // returns a unique pid for the calling thread, then look at the
1237 // OSThread::thread_id() method in osThread_bsd.hpp file
1238
1239 return (int)(_initial_pid ? _initial_pid : getpid());
1240 }
1241
1242 // DLL functions
1243
1244 #define JNI_LIB_PREFIX "lib"
1245 #ifdef __APPLE__
1246 #define JNI_LIB_SUFFIX ".dylib"
1247 #else
1248 #define JNI_LIB_SUFFIX ".so"
1249 #endif
1250
1251 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1252
1253 // This must be hard coded because it's the system's temporary
1254 // directory not the java application's temp directory, ala java.io.tmpdir.
1255 #ifdef __APPLE__
1256 // macosx has a secure per-user temporary directory
1257 char temp_path_storage[PATH_MAX];
1258 const char* os::get_temp_directory() {
1259 static char *temp_path = NULL;
1260 if (temp_path == NULL) {
1261 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1262 if (pathSize == 0 || pathSize > PATH_MAX) {
1263 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1264 }
1265 temp_path = temp_path_storage;
1266 }
1267 return temp_path;
1268 }
1269 #else /* __APPLE__ */
1270 const char* os::get_temp_directory() { return "/tmp"; }
1271 #endif /* __APPLE__ */
1272
1273 static bool file_exists(const char* filename) {
1274 struct stat statbuf;
1275 if (filename == NULL || strlen(filename) == 0) {
1276 return false;
1277 }
1278 return os::stat(filename, &statbuf) == 0;
1279 }
1280
1281 bool os::dll_build_name(char* buffer, size_t buflen,
1282 const char* pname, const char* fname) {
1283 bool retval = false;
1284 // Copied from libhpi
1285 const size_t pnamelen = pname ? strlen(pname) : 0;
1286
1287 // Return error on buffer overflow.
1288 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1289 return retval;
1290 }
1291
1292 if (pnamelen == 0) {
1293 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1294 retval = true;
1295 } else if (strchr(pname, *os::path_separator()) != NULL) {
1296 int n;
1297 char** pelements = split_path(pname, &n);
1298 if (pelements == NULL) {
1299 return false;
1300 }
1301 for (int i = 0 ; i < n ; i++) {
1302 // Really shouldn't be NULL, but check can't hurt
1303 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1304 continue; // skip the empty path values
1305 }
1306 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1307 pelements[i], fname);
1308 if (file_exists(buffer)) {
1309 retval = true;
1310 break;
1311 }
1312 }
1313 // release the storage
1314 for (int i = 0 ; i < n ; i++) {
1315 if (pelements[i] != NULL) {
1316 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1317 }
1318 }
1319 if (pelements != NULL) {
1320 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1321 }
1322 } else {
1323 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1324 retval = true;
1325 }
1326 return retval;
1327 }
1328
1329 // check if addr is inside libjvm.so
1330 bool os::address_is_in_vm(address addr) {
1331 static address libjvm_base_addr;
1332 Dl_info dlinfo;
1333
1334 if (libjvm_base_addr == NULL) {
1335 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1336 libjvm_base_addr = (address)dlinfo.dli_fbase;
1337 }
1338 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1339 }
1340
1341 if (dladdr((void *)addr, &dlinfo) != 0) {
1342 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1343 }
1344
1345 return false;
1346 }
1347
1348
1349 #define MACH_MAXSYMLEN 256
1350
1351 bool os::dll_address_to_function_name(address addr, char *buf,
1352 int buflen, int *offset) {
1353 // buf is not optional, but offset is optional
1354 assert(buf != NULL, "sanity check");
1355
1356 Dl_info dlinfo;
1357 char localbuf[MACH_MAXSYMLEN];
1358
1359 if (dladdr((void*)addr, &dlinfo) != 0) {
1360 // see if we have a matching symbol
1361 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1362 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1363 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1364 }
1365 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1366 return true;
1367 }
1368 // no matching symbol so try for just file info
1369 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1370 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1371 buf, buflen, offset, dlinfo.dli_fname)) {
1372 return true;
1373 }
1374 }
1375
1376 // Handle non-dynamic manually:
1377 if (dlinfo.dli_fbase != NULL &&
1378 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1379 dlinfo.dli_fbase)) {
1380 if (!Decoder::demangle(localbuf, buf, buflen)) {
1381 jio_snprintf(buf, buflen, "%s", localbuf);
1382 }
1383 return true;
1384 }
1385 }
1386 buf[0] = '\0';
1387 if (offset != NULL) *offset = -1;
1388 return false;
1389 }
1390
1391 // ported from solaris version
1392 bool os::dll_address_to_library_name(address addr, char* buf,
1393 int buflen, int* offset) {
1394 // buf is not optional, but offset is optional
1395 assert(buf != NULL, "sanity check");
1396
1397 Dl_info dlinfo;
1398
1399 if (dladdr((void*)addr, &dlinfo) != 0) {
1400 if (dlinfo.dli_fname != NULL) {
1401 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1402 }
1403 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1404 *offset = addr - (address)dlinfo.dli_fbase;
1405 }
1406 return true;
1407 }
1408
1409 buf[0] = '\0';
1410 if (offset) *offset = -1;
1411 return false;
1412 }
1413
1414 // Loads .dll/.so and
1415 // in case of error it checks if .dll/.so was built for the
1416 // same architecture as Hotspot is running on
1417
1418 #ifdef __APPLE__
1419 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1420 void * result= ::dlopen(filename, RTLD_LAZY);
1421 if (result != NULL) {
1422 // Successful loading
1423 return result;
1424 }
1425
1426 // Read system error message into ebuf
1427 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1428 ebuf[ebuflen-1]='\0';
1429
1430 return NULL;
1431 }
1432 #else
1433 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1434 {
1435 void * result= ::dlopen(filename, RTLD_LAZY);
1436 if (result != NULL) {
1437 // Successful loading
1438 return result;
1439 }
1440
1441 Elf32_Ehdr elf_head;
1442
1443 // Read system error message into ebuf
1444 // It may or may not be overwritten below
1445 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1446 ebuf[ebuflen-1]='\0';
1447 int diag_msg_max_length=ebuflen-strlen(ebuf);
1448 char* diag_msg_buf=ebuf+strlen(ebuf);
1449
1450 if (diag_msg_max_length==0) {
1451 // No more space in ebuf for additional diagnostics message
1452 return NULL;
1453 }
1454
1455
1456 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1457
1458 if (file_descriptor < 0) {
1459 // Can't open library, report dlerror() message
1460 return NULL;
1461 }
1462
1463 bool failed_to_read_elf_head=
1464 (sizeof(elf_head)!=
1465 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1466
1467 ::close(file_descriptor);
1468 if (failed_to_read_elf_head) {
1469 // file i/o error - report dlerror() msg
1470 return NULL;
1471 }
1472
1473 typedef struct {
1474 Elf32_Half code; // Actual value as defined in elf.h
1475 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1476 char elf_class; // 32 or 64 bit
1477 char endianess; // MSB or LSB
1478 char* name; // String representation
1479 } arch_t;
1480
1481 #ifndef EM_486
1482 #define EM_486 6 /* Intel 80486 */
1483 #endif
1484
1485 #ifndef EM_MIPS_RS3_LE
1486 #define EM_MIPS_RS3_LE 10 /* MIPS */
1487 #endif
1488
1489 #ifndef EM_PPC64
1490 #define EM_PPC64 21 /* PowerPC64 */
1491 #endif
1492
1493 #ifndef EM_S390
1494 #define EM_S390 22 /* IBM System/390 */
1495 #endif
1496
1497 #ifndef EM_IA_64
1498 #define EM_IA_64 50 /* HP/Intel IA-64 */
1499 #endif
1500
1501 #ifndef EM_X86_64
1502 #define EM_X86_64 62 /* AMD x86-64 */
1503 #endif
1504
1505 static const arch_t arch_array[]={
1506 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1507 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1508 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1509 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1510 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1511 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1512 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1513 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1514 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1515 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1516 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1517 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1518 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1519 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1520 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1521 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1522 };
1523
1524 #if (defined IA32)
1525 static Elf32_Half running_arch_code=EM_386;
1526 #elif (defined AMD64)
1527 static Elf32_Half running_arch_code=EM_X86_64;
1528 #elif (defined IA64)
1529 static Elf32_Half running_arch_code=EM_IA_64;
1530 #elif (defined __sparc) && (defined _LP64)
1531 static Elf32_Half running_arch_code=EM_SPARCV9;
1532 #elif (defined __sparc) && (!defined _LP64)
1533 static Elf32_Half running_arch_code=EM_SPARC;
1534 #elif (defined __powerpc64__)
1535 static Elf32_Half running_arch_code=EM_PPC64;
1536 #elif (defined __powerpc__)
1537 static Elf32_Half running_arch_code=EM_PPC;
1538 #elif (defined ARM)
1539 static Elf32_Half running_arch_code=EM_ARM;
1540 #elif (defined S390)
1541 static Elf32_Half running_arch_code=EM_S390;
1542 #elif (defined ALPHA)
1543 static Elf32_Half running_arch_code=EM_ALPHA;
1544 #elif (defined MIPSEL)
1545 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1546 #elif (defined PARISC)
1547 static Elf32_Half running_arch_code=EM_PARISC;
1548 #elif (defined MIPS)
1549 static Elf32_Half running_arch_code=EM_MIPS;
1550 #elif (defined M68K)
1551 static Elf32_Half running_arch_code=EM_68K;
1552 #else
1553 #error Method os::dll_load requires that one of following is defined:\
1554 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1555 #endif
1556
1557 // Identify compatability class for VM's architecture and library's architecture
1558 // Obtain string descriptions for architectures
1559
1560 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1561 int running_arch_index=-1;
1562
1563 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1564 if (running_arch_code == arch_array[i].code) {
1565 running_arch_index = i;
1566 }
1567 if (lib_arch.code == arch_array[i].code) {
1568 lib_arch.compat_class = arch_array[i].compat_class;
1569 lib_arch.name = arch_array[i].name;
1570 }
1571 }
1572
1573 assert(running_arch_index != -1,
1574 "Didn't find running architecture code (running_arch_code) in arch_array");
1575 if (running_arch_index == -1) {
1576 // Even though running architecture detection failed
1577 // we may still continue with reporting dlerror() message
1578 return NULL;
1579 }
1580
1581 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1582 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1583 return NULL;
1584 }
1585
1586 #ifndef S390
1587 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1588 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1589 return NULL;
1590 }
1591 #endif // !S390
1592
1593 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1594 if ( lib_arch.name!=NULL ) {
1595 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1596 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1597 lib_arch.name, arch_array[running_arch_index].name);
1598 } else {
1599 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1600 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1601 lib_arch.code,
1602 arch_array[running_arch_index].name);
1603 }
1604 }
1605
1606 return NULL;
1607 }
1608 #endif /* !__APPLE__ */
1609
1610 void* os::get_default_process_handle() {
1611 #ifdef __APPLE__
1612 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1613 // to avoid finding unexpected symbols on second (or later)
1614 // loads of a library.
1615 return (void*)::dlopen(NULL, RTLD_FIRST);
1616 #else
1617 return (void*)::dlopen(NULL, RTLD_LAZY);
1618 #endif
1619 }
1620
1621 // XXX: Do we need a lock around this as per Linux?
1622 void* os::dll_lookup(void* handle, const char* name) {
1623 return dlsym(handle, name);
1624 }
1625
1626
1627 static bool _print_ascii_file(const char* filename, outputStream* st) {
1628 int fd = ::open(filename, O_RDONLY);
1629 if (fd == -1) {
1630 return false;
1631 }
1632
1633 char buf[32];
1634 int bytes;
1635 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1636 st->print_raw(buf, bytes);
1637 }
1638
1639 ::close(fd);
1640
1641 return true;
1642 }
1643
1644 void os::print_dll_info(outputStream *st) {
1645 st->print_cr("Dynamic libraries:");
1646 #ifdef RTLD_DI_LINKMAP
1647 Dl_info dli;
1648 void *handle;
1649 Link_map *map;
1650 Link_map *p;
1651
1652 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1653 dli.dli_fname == NULL) {
1654 st->print_cr("Error: Cannot print dynamic libraries.");
1655 return;
1656 }
1657 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1658 if (handle == NULL) {
1659 st->print_cr("Error: Cannot print dynamic libraries.");
1660 return;
1661 }
1662 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1663 if (map == NULL) {
1664 st->print_cr("Error: Cannot print dynamic libraries.");
1665 return;
1666 }
1667
1668 while (map->l_prev != NULL)
1669 map = map->l_prev;
1670
1671 while (map != NULL) {
1672 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1673 map = map->l_next;
1674 }
1675
1676 dlclose(handle);
1677 #elif defined(__APPLE__)
1678 uint32_t count;
1679 uint32_t i;
1680
1681 count = _dyld_image_count();
1682 for (i = 1; i < count; i++) {
1683 const char *name = _dyld_get_image_name(i);
1684 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1685 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1686 }
1687 #else
1688 st->print_cr("Error: Cannot print dynamic libraries.");
1689 #endif
1690 }
1691
1692 void os::print_os_info_brief(outputStream* st) {
1693 st->print("Bsd");
1694
1695 os::Posix::print_uname_info(st);
1696 }
1697
1698 void os::print_os_info(outputStream* st) {
1699 st->print("OS:");
1700 st->print("Bsd");
1701
1702 os::Posix::print_uname_info(st);
1703
1704 os::Posix::print_rlimit_info(st);
1705
1706 os::Posix::print_load_average(st);
1707 }
1708
1709 void os::pd_print_cpu_info(outputStream* st) {
1710 // Nothing to do for now.
1711 }
1712
1713 void os::print_memory_info(outputStream* st) {
1714
1715 st->print("Memory:");
1716 st->print(" %dk page", os::vm_page_size()>>10);
1717
1718 st->print(", physical " UINT64_FORMAT "k",
1719 os::physical_memory() >> 10);
1720 st->print("(" UINT64_FORMAT "k free)",
1721 os::available_memory() >> 10);
1722 st->cr();
1723
1724 // meminfo
1725 st->print("\n/proc/meminfo:\n");
1726 _print_ascii_file("/proc/meminfo", st);
1727 st->cr();
1728 }
1729
1730 void os::print_siginfo(outputStream* st, void* siginfo) {
1731 const siginfo_t* si = (const siginfo_t*)siginfo;
1732
1733 os::Posix::print_siginfo_brief(st, si);
1734
1735 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1736 UseSharedSpaces) {
1737 FileMapInfo* mapinfo = FileMapInfo::current_info();
1738 if (mapinfo->is_in_shared_space(si->si_addr)) {
1739 st->print("\n\nError accessing class data sharing archive." \
1740 " Mapped file inaccessible during execution, " \
1741 " possible disk/network problem.");
1742 }
1743 }
1744 st->cr();
1745 }
1746
1747
1748 static void print_signal_handler(outputStream* st, int sig,
1749 char* buf, size_t buflen);
1750
1751 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1752 st->print_cr("Signal Handlers:");
1753 print_signal_handler(st, SIGSEGV, buf, buflen);
1754 print_signal_handler(st, SIGBUS , buf, buflen);
1755 print_signal_handler(st, SIGFPE , buf, buflen);
1756 print_signal_handler(st, SIGPIPE, buf, buflen);
1757 print_signal_handler(st, SIGXFSZ, buf, buflen);
1758 print_signal_handler(st, SIGILL , buf, buflen);
1759 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1760 print_signal_handler(st, SR_signum, buf, buflen);
1761 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1762 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1763 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1764 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1765 }
1766
1767 static char saved_jvm_path[MAXPATHLEN] = {0};
1768
1769 // Find the full path to the current module, libjvm
1770 void os::jvm_path(char *buf, jint buflen) {
1771 // Error checking.
1772 if (buflen < MAXPATHLEN) {
1773 assert(false, "must use a large-enough buffer");
1774 buf[0] = '\0';
1775 return;
1776 }
1777 // Lazy resolve the path to current module.
1778 if (saved_jvm_path[0] != 0) {
1779 strcpy(buf, saved_jvm_path);
1780 return;
1781 }
1782
1783 char dli_fname[MAXPATHLEN];
1784 bool ret = dll_address_to_library_name(
1785 CAST_FROM_FN_PTR(address, os::jvm_path),
1786 dli_fname, sizeof(dli_fname), NULL);
1787 assert(ret, "cannot locate libjvm");
1788 char *rp = NULL;
1789 if (ret && dli_fname[0] != '\0') {
1790 rp = realpath(dli_fname, buf);
1791 }
1792 if (rp == NULL)
1793 return;
1794
1795 if (Arguments::created_by_gamma_launcher()) {
1796 // Support for the gamma launcher. Typical value for buf is
1797 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1798 // the right place in the string, then assume we are installed in a JDK and
1799 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1800 // construct a path to the JVM being overridden.
1801
1802 const char *p = buf + strlen(buf) - 1;
1803 for (int count = 0; p > buf && count < 5; ++count) {
1804 for (--p; p > buf && *p != '/'; --p)
1805 /* empty */ ;
1806 }
1807
1808 if (strncmp(p, "/jre/lib/", 9) != 0) {
1809 // Look for JAVA_HOME in the environment.
1810 char* java_home_var = ::getenv("JAVA_HOME");
1811 if (java_home_var != NULL && java_home_var[0] != 0) {
1812 char* jrelib_p;
1813 int len;
1814
1815 // Check the current module name "libjvm"
1816 p = strrchr(buf, '/');
1817 assert(strstr(p, "/libjvm") == p, "invalid library name");
1818
1819 rp = realpath(java_home_var, buf);
1820 if (rp == NULL)
1821 return;
1822
1823 // determine if this is a legacy image or modules image
1824 // modules image doesn't have "jre" subdirectory
1825 len = strlen(buf);
1826 assert(len < buflen, "Ran out of buffer space");
1827 jrelib_p = buf + len;
1828
1829 // Add the appropriate library subdir
1830 snprintf(jrelib_p, buflen-len, "/jre/lib");
1831 if (0 != access(buf, F_OK)) {
1832 snprintf(jrelib_p, buflen-len, "/lib");
1833 }
1834
1835 // Add the appropriate client or server subdir
1836 len = strlen(buf);
1837 jrelib_p = buf + len;
1838 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1839 if (0 != access(buf, F_OK)) {
1840 snprintf(jrelib_p, buflen-len, "");
1841 }
1842
1843 // If the path exists within JAVA_HOME, add the JVM library name
1844 // to complete the path to JVM being overridden. Otherwise fallback
1845 // to the path to the current library.
1846 if (0 == access(buf, F_OK)) {
1847 // Use current module name "libjvm"
1848 len = strlen(buf);
1849 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1850 } else {
1851 // Fall back to path of current library
1852 rp = realpath(dli_fname, buf);
1853 if (rp == NULL)
1854 return;
1855 }
1856 }
1857 }
1858 }
1859
1860 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1861 }
1862
1863 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1864 // no prefix required, not even "_"
1865 }
1866
1867 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1868 // no suffix required
1869 }
1870
1871 ////////////////////////////////////////////////////////////////////////////////
1872 // sun.misc.Signal support
1873
1874 static volatile jint sigint_count = 0;
1875
1876 static void
1877 UserHandler(int sig, void *siginfo, void *context) {
1878 // 4511530 - sem_post is serialized and handled by the manager thread. When
1879 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1880 // don't want to flood the manager thread with sem_post requests.
1881 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1882 return;
1883
1884 // Ctrl-C is pressed during error reporting, likely because the error
1885 // handler fails to abort. Let VM die immediately.
1886 if (sig == SIGINT && is_error_reported()) {
1887 os::die();
1888 }
1889
1890 os::signal_notify(sig);
1891 }
1892
1893 void* os::user_handler() {
1894 return CAST_FROM_FN_PTR(void*, UserHandler);
1895 }
1896
1897 extern "C" {
1898 typedef void (*sa_handler_t)(int);
1899 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1900 }
1901
1902 void* os::signal(int signal_number, void* handler) {
1903 struct sigaction sigAct, oldSigAct;
1904
1905 sigfillset(&(sigAct.sa_mask));
1906 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1907 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1908
1909 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1910 // -1 means registration failed
1911 return (void *)-1;
1912 }
1913
1914 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1915 }
1916
1917 void os::signal_raise(int signal_number) {
1918 ::raise(signal_number);
1919 }
1920
1921 /*
1922 * The following code is moved from os.cpp for making this
1923 * code platform specific, which it is by its very nature.
1924 */
1925
1926 // Will be modified when max signal is changed to be dynamic
1927 int os::sigexitnum_pd() {
1928 return NSIG;
1929 }
1930
1931 // a counter for each possible signal value
1932 static volatile jint pending_signals[NSIG+1] = { 0 };
1933
1934 // Bsd(POSIX) specific hand shaking semaphore.
1935 #ifdef __APPLE__
1936 typedef semaphore_t os_semaphore_t;
1937 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1938 #define SEM_WAIT(sem) semaphore_wait(sem)
1939 #define SEM_POST(sem) semaphore_signal(sem)
1940 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1941 #else
1942 typedef sem_t os_semaphore_t;
1943 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1944 #define SEM_WAIT(sem) sem_wait(&sem)
1945 #define SEM_POST(sem) sem_post(&sem)
1946 #define SEM_DESTROY(sem) sem_destroy(&sem)
1947 #endif
1948
1949 class Semaphore : public StackObj {
1950 public:
1951 Semaphore();
1952 ~Semaphore();
1953 void signal();
1954 void wait();
1955 bool trywait();
1956 bool timedwait(unsigned int sec, int nsec);
1957 private:
1958 jlong currenttime() const;
1959 os_semaphore_t _semaphore;
1960 };
1961
1962 Semaphore::Semaphore() : _semaphore(0) {
1963 SEM_INIT(_semaphore, 0);
1964 }
1965
1966 Semaphore::~Semaphore() {
1967 SEM_DESTROY(_semaphore);
1968 }
1969
1970 void Semaphore::signal() {
1971 SEM_POST(_semaphore);
1972 }
1973
1974 void Semaphore::wait() {
1975 SEM_WAIT(_semaphore);
1976 }
1977
1978 jlong Semaphore::currenttime() const {
1979 struct timeval tv;
1980 gettimeofday(&tv, NULL);
1981 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1982 }
1983
1984 #ifdef __APPLE__
1985 bool Semaphore::trywait() {
1986 return timedwait(0, 0);
1987 }
1988
1989 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1990 kern_return_t kr = KERN_ABORTED;
1991 mach_timespec_t waitspec;
1992 waitspec.tv_sec = sec;
1993 waitspec.tv_nsec = nsec;
1994
1995 jlong starttime = currenttime();
1996
1997 kr = semaphore_timedwait(_semaphore, waitspec);
1998 while (kr == KERN_ABORTED) {
1999 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
2000
2001 jlong current = currenttime();
2002 jlong passedtime = current - starttime;
2003
2004 if (passedtime >= totalwait) {
2005 waitspec.tv_sec = 0;
2006 waitspec.tv_nsec = 0;
2007 } else {
2008 jlong waittime = totalwait - (current - starttime);
2009 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2010 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2011 }
2012
2013 kr = semaphore_timedwait(_semaphore, waitspec);
2014 }
2015
2016 return kr == KERN_SUCCESS;
2017 }
2018
2019 #else
2020
2021 bool Semaphore::trywait() {
2022 return sem_trywait(&_semaphore) == 0;
2023 }
2024
2025 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2026 struct timespec ts;
2027 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2028
2029 while (1) {
2030 int result = sem_timedwait(&_semaphore, &ts);
2031 if (result == 0) {
2032 return true;
2033 } else if (errno == EINTR) {
2034 continue;
2035 } else if (errno == ETIMEDOUT) {
2036 return false;
2037 } else {
2038 return false;
2039 }
2040 }
2041 }
2042
2043 #endif // __APPLE__
2044
2045 static os_semaphore_t sig_sem;
2046 static Semaphore sr_semaphore;
2047
2048 void os::signal_init_pd() {
2049 // Initialize signal structures
2050 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2051
2052 // Initialize signal semaphore
2053 ::SEM_INIT(sig_sem, 0);
2054 }
2055
2056 void os::signal_notify(int sig) {
2057 Atomic::inc(&pending_signals[sig]);
2058 ::SEM_POST(sig_sem);
2059 }
2060
2061 static int check_pending_signals(bool wait) {
2062 Atomic::store(0, &sigint_count);
2063 for (;;) {
2064 for (int i = 0; i < NSIG + 1; i++) {
2065 jint n = pending_signals[i];
2066 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2067 return i;
2068 }
2069 }
2070 if (!wait) {
2071 return -1;
2072 }
2073 JavaThread *thread = JavaThread::current();
2074 ThreadBlockInVM tbivm(thread);
2075
2076 bool threadIsSuspended;
2077 do {
2078 thread->set_suspend_equivalent();
2079 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2080 ::SEM_WAIT(sig_sem);
2081
2082 // were we externally suspended while we were waiting?
2083 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2084 if (threadIsSuspended) {
2085 //
2086 // The semaphore has been incremented, but while we were waiting
2087 // another thread suspended us. We don't want to continue running
2088 // while suspended because that would surprise the thread that
2089 // suspended us.
2090 //
2091 ::SEM_POST(sig_sem);
2092
2093 thread->java_suspend_self();
2094 }
2095 } while (threadIsSuspended);
2096 }
2097 }
2098
2099 int os::signal_lookup() {
2100 return check_pending_signals(false);
2101 }
2102
2103 int os::signal_wait() {
2104 return check_pending_signals(true);
2105 }
2106
2107 ////////////////////////////////////////////////////////////////////////////////
2108 // Virtual Memory
2109
2110 int os::vm_page_size() {
2111 // Seems redundant as all get out
2112 assert(os::Bsd::page_size() != -1, "must call os::init");
2113 return os::Bsd::page_size();
2114 }
2115
2116 // Solaris allocates memory by pages.
2117 int os::vm_allocation_granularity() {
2118 assert(os::Bsd::page_size() != -1, "must call os::init");
2119 return os::Bsd::page_size();
2120 }
2121
2122 // Rationale behind this function:
2123 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2124 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2125 // samples for JITted code. Here we create private executable mapping over the code cache
2126 // and then we can use standard (well, almost, as mapping can change) way to provide
2127 // info for the reporting script by storing timestamp and location of symbol
2128 void bsd_wrap_code(char* base, size_t size) {
2129 static volatile jint cnt = 0;
2130
2131 if (!UseOprofile) {
2132 return;
2133 }
2134
2135 char buf[PATH_MAX + 1];
2136 int num = Atomic::add(1, &cnt);
2137
2138 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2139 os::get_temp_directory(), os::current_process_id(), num);
2140 unlink(buf);
2141
2142 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2143
2144 if (fd != -1) {
2145 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2146 if (rv != (off_t)-1) {
2147 if (::write(fd, "", 1) == 1) {
2148 mmap(base, size,
2149 PROT_READ|PROT_WRITE|PROT_EXEC,
2150 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2151 }
2152 }
2153 ::close(fd);
2154 unlink(buf);
2155 }
2156 }
2157
2158 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2159 int err) {
2160 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2161 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2162 strerror(err), err);
2163 }
2164
2165 // NOTE: Bsd kernel does not really reserve the pages for us.
2166 // All it does is to check if there are enough free pages
2167 // left at the time of mmap(). This could be a potential
2168 // problem.
2169 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2170 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2171 #ifdef __OpenBSD__
2172 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2173 if (::mprotect(addr, size, prot) == 0) {
2174 return true;
2175 }
2176 #else
2177 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2178 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2179 if (res != (uintptr_t) MAP_FAILED) {
2180 return true;
2181 }
2182 #endif
2183
2184 // Warn about any commit errors we see in non-product builds just
2185 // in case mmap() doesn't work as described on the man page.
2186 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2187
2188 return false;
2189 }
2190
2191 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2192 bool exec) {
2193 // alignment_hint is ignored on this OS
2194 return pd_commit_memory(addr, size, exec);
2195 }
2196
2197 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2198 const char* mesg) {
2199 assert(mesg != NULL, "mesg must be specified");
2200 if (!pd_commit_memory(addr, size, exec)) {
2201 // add extra info in product mode for vm_exit_out_of_memory():
2202 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2203 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2204 }
2205 }
2206
2207 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2208 size_t alignment_hint, bool exec,
2209 const char* mesg) {
2210 // alignment_hint is ignored on this OS
2211 pd_commit_memory_or_exit(addr, size, exec, mesg);
2212 }
2213
2214 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2215 }
2216
2217 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2218 ::madvise(addr, bytes, MADV_DONTNEED);
2219 }
2220
2221 void os::numa_make_global(char *addr, size_t bytes) {
2222 }
2223
2224 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2225 }
2226
2227 bool os::numa_topology_changed() { return false; }
2228
2229 size_t os::numa_get_groups_num() {
2230 return 1;
2231 }
2232
2233 int os::numa_get_group_id() {
2234 return 0;
2235 }
2236
2237 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2238 if (size > 0) {
2239 ids[0] = 0;
2240 return 1;
2241 }
2242 return 0;
2243 }
2244
2245 bool os::get_page_info(char *start, page_info* info) {
2246 return false;
2247 }
2248
2249 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2250 return end;
2251 }
2252
2253
2254 bool os::pd_uncommit_memory(char* addr, size_t size) {
2255 #ifdef __OpenBSD__
2256 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2257 return ::mprotect(addr, size, PROT_NONE) == 0;
2258 #else
2259 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2260 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2261 return res != (uintptr_t) MAP_FAILED;
2262 #endif
2263 }
2264
2265 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2266 return os::commit_memory(addr, size, !ExecMem);
2267 }
2268
2269 // If this is a growable mapping, remove the guard pages entirely by
2270 // munmap()ping them. If not, just call uncommit_memory().
2271 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2272 return os::uncommit_memory(addr, size);
2273 }
2274
2275 static address _highest_vm_reserved_address = NULL;
2276
2277 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2278 // at 'requested_addr'. If there are existing memory mappings at the same
2279 // location, however, they will be overwritten. If 'fixed' is false,
2280 // 'requested_addr' is only treated as a hint, the return value may or
2281 // may not start from the requested address. Unlike Bsd mmap(), this
2282 // function returns NULL to indicate failure.
2283 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2284 char * addr;
2285 int flags;
2286
2287 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2288 if (fixed) {
2289 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2290 flags |= MAP_FIXED;
2291 }
2292
2293 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2294 // touch an uncommitted page. Otherwise, the read/write might
2295 // succeed if we have enough swap space to back the physical page.
2296 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2297 flags, -1, 0);
2298
2299 if (addr != MAP_FAILED) {
2300 // anon_mmap() should only get called during VM initialization,
2301 // don't need lock (actually we can skip locking even it can be called
2302 // from multiple threads, because _highest_vm_reserved_address is just a
2303 // hint about the upper limit of non-stack memory regions.)
2304 if ((address)addr + bytes > _highest_vm_reserved_address) {
2305 _highest_vm_reserved_address = (address)addr + bytes;
2306 }
2307 }
2308
2309 return addr == MAP_FAILED ? NULL : addr;
2310 }
2311
2312 // Don't update _highest_vm_reserved_address, because there might be memory
2313 // regions above addr + size. If so, releasing a memory region only creates
2314 // a hole in the address space, it doesn't help prevent heap-stack collision.
2315 //
2316 static int anon_munmap(char * addr, size_t size) {
2317 return ::munmap(addr, size) == 0;
2318 }
2319
2320 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2321 size_t alignment_hint) {
2322 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2323 }
2324
2325 bool os::pd_release_memory(char* addr, size_t size) {
2326 return anon_munmap(addr, size);
2327 }
2328
2329 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2330 // Bsd wants the mprotect address argument to be page aligned.
2331 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2332
2333 // According to SUSv3, mprotect() should only be used with mappings
2334 // established by mmap(), and mmap() always maps whole pages. Unaligned
2335 // 'addr' likely indicates problem in the VM (e.g. trying to change
2336 // protection of malloc'ed or statically allocated memory). Check the
2337 // caller if you hit this assert.
2338 assert(addr == bottom, "sanity check");
2339
2340 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2341 return ::mprotect(bottom, size, prot) == 0;
2342 }
2343
2344 // Set protections specified
2345 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2346 bool is_committed) {
2347 unsigned int p = 0;
2348 switch (prot) {
2349 case MEM_PROT_NONE: p = PROT_NONE; break;
2350 case MEM_PROT_READ: p = PROT_READ; break;
2351 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2352 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2353 default:
2354 ShouldNotReachHere();
2355 }
2356 // is_committed is unused.
2357 return bsd_mprotect(addr, bytes, p);
2358 }
2359
2360 bool os::guard_memory(char* addr, size_t size) {
2361 return bsd_mprotect(addr, size, PROT_NONE);
2362 }
2363
2364 bool os::unguard_memory(char* addr, size_t size) {
2365 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2366 }
2367
2368 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2369 return false;
2370 }
2371
2372 // Large page support
2373
2374 static size_t _large_page_size = 0;
2375
2376 void os::large_page_init() {
2377 }
2378
2379
2380 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2381 fatal("This code is not used or maintained.");
2382
2383 // "exec" is passed in but not used. Creating the shared image for
2384 // the code cache doesn't have an SHM_X executable permission to check.
2385 assert(UseLargePages && UseSHM, "only for SHM large pages");
2386
2387 key_t key = IPC_PRIVATE;
2388 char *addr;
2389
2390 bool warn_on_failure = UseLargePages &&
2391 (!FLAG_IS_DEFAULT(UseLargePages) ||
2392 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2393 );
2394
2395 // Create a large shared memory region to attach to based on size.
2396 // Currently, size is the total size of the heap
2397 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2398 if (shmid == -1) {
2399 // Possible reasons for shmget failure:
2400 // 1. shmmax is too small for Java heap.
2401 // > check shmmax value: cat /proc/sys/kernel/shmmax
2402 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2403 // 2. not enough large page memory.
2404 // > check available large pages: cat /proc/meminfo
2405 // > increase amount of large pages:
2406 // echo new_value > /proc/sys/vm/nr_hugepages
2407 // Note 1: different Bsd may use different name for this property,
2408 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2409 // Note 2: it's possible there's enough physical memory available but
2410 // they are so fragmented after a long run that they can't
2411 // coalesce into large pages. Try to reserve large pages when
2412 // the system is still "fresh".
2413 if (warn_on_failure) {
2414 warning("Failed to reserve shared memory (errno = %d).", errno);
2415 }
2416 return NULL;
2417 }
2418
2419 // attach to the region
2420 addr = (char*)shmat(shmid, req_addr, 0);
2421 int err = errno;
2422
2423 // Remove shmid. If shmat() is successful, the actual shared memory segment
2424 // will be deleted when it's detached by shmdt() or when the process
2425 // terminates. If shmat() is not successful this will remove the shared
2426 // segment immediately.
2427 shmctl(shmid, IPC_RMID, NULL);
2428
2429 if ((intptr_t)addr == -1) {
2430 if (warn_on_failure) {
2431 warning("Failed to attach shared memory (errno = %d).", err);
2432 }
2433 return NULL;
2434 }
2435
2436 // The memory is committed
2437 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2438
2439 return addr;
2440 }
2441
2442 bool os::release_memory_special(char* base, size_t bytes) {
2443 if (MemTracker::tracking_level() > NMT_minimal) {
2444 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2445 // detaching the SHM segment will also delete it, see reserve_memory_special()
2446 int rslt = shmdt(base);
2447 if (rslt == 0) {
2448 tkr.record((address)base, bytes);
2449 return true;
2450 } else {
2451 return false;
2452 }
2453 } else {
2454 return shmdt(base) == 0;
2455 }
2456 }
2457
2458 size_t os::large_page_size() {
2459 return _large_page_size;
2460 }
2461
2462 // HugeTLBFS allows application to commit large page memory on demand;
2463 // with SysV SHM the entire memory region must be allocated as shared
2464 // memory.
2465 bool os::can_commit_large_page_memory() {
2466 return UseHugeTLBFS;
2467 }
2468
2469 bool os::can_execute_large_page_memory() {
2470 return UseHugeTLBFS;
2471 }
2472
2473 // Reserve memory at an arbitrary address, only if that area is
2474 // available (and not reserved for something else).
2475
2476 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2477 const int max_tries = 10;
2478 char* base[max_tries];
2479 size_t size[max_tries];
2480 const size_t gap = 0x000000;
2481
2482 // Assert only that the size is a multiple of the page size, since
2483 // that's all that mmap requires, and since that's all we really know
2484 // about at this low abstraction level. If we need higher alignment,
2485 // we can either pass an alignment to this method or verify alignment
2486 // in one of the methods further up the call chain. See bug 5044738.
2487 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2488
2489 // Repeatedly allocate blocks until the block is allocated at the
2490 // right spot. Give up after max_tries. Note that reserve_memory() will
2491 // automatically update _highest_vm_reserved_address if the call is
2492 // successful. The variable tracks the highest memory address every reserved
2493 // by JVM. It is used to detect heap-stack collision if running with
2494 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2495 // space than needed, it could confuse the collision detecting code. To
2496 // solve the problem, save current _highest_vm_reserved_address and
2497 // calculate the correct value before return.
2498 address old_highest = _highest_vm_reserved_address;
2499
2500 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2501 // if kernel honors the hint then we can return immediately.
2502 char * addr = anon_mmap(requested_addr, bytes, false);
2503 if (addr == requested_addr) {
2504 return requested_addr;
2505 }
2506
2507 if (addr != NULL) {
2508 // mmap() is successful but it fails to reserve at the requested address
2509 anon_munmap(addr, bytes);
2510 }
2511
2512 int i;
2513 for (i = 0; i < max_tries; ++i) {
2514 base[i] = reserve_memory(bytes);
2515
2516 if (base[i] != NULL) {
2517 // Is this the block we wanted?
2518 if (base[i] == requested_addr) {
2519 size[i] = bytes;
2520 break;
2521 }
2522
2523 // Does this overlap the block we wanted? Give back the overlapped
2524 // parts and try again.
2525
2526 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2527 if (top_overlap >= 0 && top_overlap < bytes) {
2528 unmap_memory(base[i], top_overlap);
2529 base[i] += top_overlap;
2530 size[i] = bytes - top_overlap;
2531 } else {
2532 size_t bottom_overlap = base[i] + bytes - requested_addr;
2533 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2534 unmap_memory(requested_addr, bottom_overlap);
2535 size[i] = bytes - bottom_overlap;
2536 } else {
2537 size[i] = bytes;
2538 }
2539 }
2540 }
2541 }
2542
2543 // Give back the unused reserved pieces.
2544
2545 for (int j = 0; j < i; ++j) {
2546 if (base[j] != NULL) {
2547 unmap_memory(base[j], size[j]);
2548 }
2549 }
2550
2551 if (i < max_tries) {
2552 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2553 return requested_addr;
2554 } else {
2555 _highest_vm_reserved_address = old_highest;
2556 return NULL;
2557 }
2558 }
2559
2560 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2561 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2562 }
2563
2564 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2565 // Solaris uses poll(), bsd uses park().
2566 // Poll() is likely a better choice, assuming that Thread.interrupt()
2567 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2568 // SIGSEGV, see 4355769.
2569
2570 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2571 assert(thread == Thread::current(), "thread consistency check");
2572
2573 ParkEvent * const slp = thread->_SleepEvent ;
2574 slp->reset() ;
2575 OrderAccess::fence() ;
2576
2577 if (interruptible) {
2578 jlong prevtime = javaTimeNanos();
2579
2580 for (;;) {
2581 if (os::is_interrupted(thread, true)) {
2582 return OS_INTRPT;
2583 }
2584
2585 jlong newtime = javaTimeNanos();
2586
2587 if (newtime - prevtime < 0) {
2588 // time moving backwards, should only happen if no monotonic clock
2589 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2590 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2591 } else {
2592 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2593 }
2594
2595 if(millis <= 0) {
2596 return OS_OK;
2597 }
2598
2599 prevtime = newtime;
2600
2601 {
2602 assert(thread->is_Java_thread(), "sanity check");
2603 JavaThread *jt = (JavaThread *) thread;
2604 ThreadBlockInVM tbivm(jt);
2605 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2606
2607 jt->set_suspend_equivalent();
2608 // cleared by handle_special_suspend_equivalent_condition() or
2609 // java_suspend_self() via check_and_wait_while_suspended()
2610
2611 slp->park(millis);
2612
2613 // were we externally suspended while we were waiting?
2614 jt->check_and_wait_while_suspended();
2615 }
2616 }
2617 } else {
2618 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2619 jlong prevtime = javaTimeNanos();
2620
2621 for (;;) {
2622 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2623 // the 1st iteration ...
2624 jlong newtime = javaTimeNanos();
2625
2626 if (newtime - prevtime < 0) {
2627 // time moving backwards, should only happen if no monotonic clock
2628 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2629 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2630 } else {
2631 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2632 }
2633
2634 if(millis <= 0) break ;
2635
2636 prevtime = newtime;
2637 slp->park(millis);
2638 }
2639 return OS_OK ;
2640 }
2641 }
2642
2643 void os::naked_short_sleep(jlong ms) {
2644 struct timespec req;
2645
2646 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2647 req.tv_sec = 0;
2648 if (ms > 0) {
2649 req.tv_nsec = (ms % 1000) * 1000000;
2650 }
2651 else {
2652 req.tv_nsec = 1;
2653 }
2654
2655 nanosleep(&req, NULL);
2656
2657 return;
2658 }
2659
2660 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2661 void os::infinite_sleep() {
2662 while (true) { // sleep forever ...
2663 ::sleep(100); // ... 100 seconds at a time
2664 }
2665 }
2666
2667 // Used to convert frequent JVM_Yield() to nops
2668 bool os::dont_yield() {
2669 return DontYieldALot;
2670 }
2671
2672 void os::yield() {
2673 sched_yield();
2674 }
2675
2676 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2677
2678 void os::yield_all(int attempts) {
2679 // Yields to all threads, including threads with lower priorities
2680 // Threads on Bsd are all with same priority. The Solaris style
2681 // os::yield_all() with nanosleep(1ms) is not necessary.
2682 sched_yield();
2683 }
2684
2685 // Called from the tight loops to possibly influence time-sharing heuristics
2686 void os::loop_breaker(int attempts) {
2687 os::yield_all(attempts);
2688 }
2689
2690 ////////////////////////////////////////////////////////////////////////////////
2691 // thread priority support
2692
2693 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2694 // only supports dynamic priority, static priority must be zero. For real-time
2695 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2696 // However, for large multi-threaded applications, SCHED_RR is not only slower
2697 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2698 // of 5 runs - Sep 2005).
2699 //
2700 // The following code actually changes the niceness of kernel-thread/LWP. It
2701 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2702 // not the entire user process, and user level threads are 1:1 mapped to kernel
2703 // threads. It has always been the case, but could change in the future. For
2704 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2705 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2706
2707 #if !defined(__APPLE__)
2708 int os::java_to_os_priority[CriticalPriority + 1] = {
2709 19, // 0 Entry should never be used
2710
2711 0, // 1 MinPriority
2712 3, // 2
2713 6, // 3
2714
2715 10, // 4
2716 15, // 5 NormPriority
2717 18, // 6
2718
2719 21, // 7
2720 25, // 8
2721 28, // 9 NearMaxPriority
2722
2723 31, // 10 MaxPriority
2724
2725 31 // 11 CriticalPriority
2726 };
2727 #else
2728 /* Using Mach high-level priority assignments */
2729 int os::java_to_os_priority[CriticalPriority + 1] = {
2730 0, // 0 Entry should never be used (MINPRI_USER)
2731
2732 27, // 1 MinPriority
2733 28, // 2
2734 29, // 3
2735
2736 30, // 4
2737 31, // 5 NormPriority (BASEPRI_DEFAULT)
2738 32, // 6
2739
2740 33, // 7
2741 34, // 8
2742 35, // 9 NearMaxPriority
2743
2744 36, // 10 MaxPriority
2745
2746 36 // 11 CriticalPriority
2747 };
2748 #endif
2749
2750 static int prio_init() {
2751 if (ThreadPriorityPolicy == 1) {
2752 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2753 // if effective uid is not root. Perhaps, a more elegant way of doing
2754 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2755 if (geteuid() != 0) {
2756 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2757 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2758 }
2759 ThreadPriorityPolicy = 0;
2760 }
2761 }
2762 if (UseCriticalJavaThreadPriority) {
2763 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2764 }
2765 return 0;
2766 }
2767
2768 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2769 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2770
2771 #ifdef __OpenBSD__
2772 // OpenBSD pthread_setprio starves low priority threads
2773 return OS_OK;
2774 #elif defined(__FreeBSD__)
2775 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2776 #elif defined(__APPLE__) || defined(__NetBSD__)
2777 struct sched_param sp;
2778 int policy;
2779 pthread_t self = pthread_self();
2780
2781 if (pthread_getschedparam(self, &policy, &sp) != 0)
2782 return OS_ERR;
2783
2784 sp.sched_priority = newpri;
2785 if (pthread_setschedparam(self, policy, &sp) != 0)
2786 return OS_ERR;
2787
2788 return OS_OK;
2789 #else
2790 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2791 return (ret == 0) ? OS_OK : OS_ERR;
2792 #endif
2793 }
2794
2795 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2796 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2797 *priority_ptr = java_to_os_priority[NormPriority];
2798 return OS_OK;
2799 }
2800
2801 errno = 0;
2802 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2803 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2804 #elif defined(__APPLE__) || defined(__NetBSD__)
2805 int policy;
2806 struct sched_param sp;
2807
2808 pthread_getschedparam(pthread_self(), &policy, &sp);
2809 *priority_ptr = sp.sched_priority;
2810 #else
2811 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2812 #endif
2813 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2814 }
2815
2816 // Hint to the underlying OS that a task switch would not be good.
2817 // Void return because it's a hint and can fail.
2818 void os::hint_no_preempt() {}
2819
2820 ////////////////////////////////////////////////////////////////////////////////
2821 // suspend/resume support
2822
2823 // the low-level signal-based suspend/resume support is a remnant from the
2824 // old VM-suspension that used to be for java-suspension, safepoints etc,
2825 // within hotspot. Now there is a single use-case for this:
2826 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2827 // that runs in the watcher thread.
2828 // The remaining code is greatly simplified from the more general suspension
2829 // code that used to be used.
2830 //
2831 // The protocol is quite simple:
2832 // - suspend:
2833 // - sends a signal to the target thread
2834 // - polls the suspend state of the osthread using a yield loop
2835 // - target thread signal handler (SR_handler) sets suspend state
2836 // and blocks in sigsuspend until continued
2837 // - resume:
2838 // - sets target osthread state to continue
2839 // - sends signal to end the sigsuspend loop in the SR_handler
2840 //
2841 // Note that the SR_lock plays no role in this suspend/resume protocol.
2842 //
2843
2844 static void resume_clear_context(OSThread *osthread) {
2845 osthread->set_ucontext(NULL);
2846 osthread->set_siginfo(NULL);
2847 }
2848
2849 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2850 osthread->set_ucontext(context);
2851 osthread->set_siginfo(siginfo);
2852 }
2853
2854 //
2855 // Handler function invoked when a thread's execution is suspended or
2856 // resumed. We have to be careful that only async-safe functions are
2857 // called here (Note: most pthread functions are not async safe and
2858 // should be avoided.)
2859 //
2860 // Note: sigwait() is a more natural fit than sigsuspend() from an
2861 // interface point of view, but sigwait() prevents the signal hander
2862 // from being run. libpthread would get very confused by not having
2863 // its signal handlers run and prevents sigwait()'s use with the
2864 // mutex granting granting signal.
2865 //
2866 // Currently only ever called on the VMThread or JavaThread
2867 //
2868 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2869 // Save and restore errno to avoid confusing native code with EINTR
2870 // after sigsuspend.
2871 int old_errno = errno;
2872
2873 Thread* thread = Thread::current();
2874 OSThread* osthread = thread->osthread();
2875 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2876
2877 os::SuspendResume::State current = osthread->sr.state();
2878 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2879 suspend_save_context(osthread, siginfo, context);
2880
2881 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2882 os::SuspendResume::State state = osthread->sr.suspended();
2883 if (state == os::SuspendResume::SR_SUSPENDED) {
2884 sigset_t suspend_set; // signals for sigsuspend()
2885
2886 // get current set of blocked signals and unblock resume signal
2887 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2888 sigdelset(&suspend_set, SR_signum);
2889
2890 sr_semaphore.signal();
2891 // wait here until we are resumed
2892 while (1) {
2893 sigsuspend(&suspend_set);
2894
2895 os::SuspendResume::State result = osthread->sr.running();
2896 if (result == os::SuspendResume::SR_RUNNING) {
2897 sr_semaphore.signal();
2898 break;
2899 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2900 ShouldNotReachHere();
2901 }
2902 }
2903
2904 } else if (state == os::SuspendResume::SR_RUNNING) {
2905 // request was cancelled, continue
2906 } else {
2907 ShouldNotReachHere();
2908 }
2909
2910 resume_clear_context(osthread);
2911 } else if (current == os::SuspendResume::SR_RUNNING) {
2912 // request was cancelled, continue
2913 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2914 // ignore
2915 } else {
2916 // ignore
2917 }
2918
2919 errno = old_errno;
2920 }
2921
2922
2923 static int SR_initialize() {
2924 struct sigaction act;
2925 char *s;
2926 /* Get signal number to use for suspend/resume */
2927 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2928 int sig = ::strtol(s, 0, 10);
2929 if (sig > 0 || sig < NSIG) {
2930 SR_signum = sig;
2931 }
2932 }
2933
2934 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2935 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2936
2937 sigemptyset(&SR_sigset);
2938 sigaddset(&SR_sigset, SR_signum);
2939
2940 /* Set up signal handler for suspend/resume */
2941 act.sa_flags = SA_RESTART|SA_SIGINFO;
2942 act.sa_handler = (void (*)(int)) SR_handler;
2943
2944 // SR_signum is blocked by default.
2945 // 4528190 - We also need to block pthread restart signal (32 on all
2946 // supported Bsd platforms). Note that BsdThreads need to block
2947 // this signal for all threads to work properly. So we don't have
2948 // to use hard-coded signal number when setting up the mask.
2949 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2950
2951 if (sigaction(SR_signum, &act, 0) == -1) {
2952 return -1;
2953 }
2954
2955 // Save signal flag
2956 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2957 return 0;
2958 }
2959
2960 static int sr_notify(OSThread* osthread) {
2961 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2962 assert_status(status == 0, status, "pthread_kill");
2963 return status;
2964 }
2965
2966 // "Randomly" selected value for how long we want to spin
2967 // before bailing out on suspending a thread, also how often
2968 // we send a signal to a thread we want to resume
2969 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2970 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2971
2972 // returns true on success and false on error - really an error is fatal
2973 // but this seems the normal response to library errors
2974 static bool do_suspend(OSThread* osthread) {
2975 assert(osthread->sr.is_running(), "thread should be running");
2976 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2977
2978 // mark as suspended and send signal
2979 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2980 // failed to switch, state wasn't running?
2981 ShouldNotReachHere();
2982 return false;
2983 }
2984
2985 if (sr_notify(osthread) != 0) {
2986 ShouldNotReachHere();
2987 }
2988
2989 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2990 while (true) {
2991 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2992 break;
2993 } else {
2994 // timeout
2995 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2996 if (cancelled == os::SuspendResume::SR_RUNNING) {
2997 return false;
2998 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2999 // make sure that we consume the signal on the semaphore as well
3000 sr_semaphore.wait();
3001 break;
3002 } else {
3003 ShouldNotReachHere();
3004 return false;
3005 }
3006 }
3007 }
3008
3009 guarantee(osthread->sr.is_suspended(), "Must be suspended");
3010 return true;
3011 }
3012
3013 static void do_resume(OSThread* osthread) {
3014 assert(osthread->sr.is_suspended(), "thread should be suspended");
3015 assert(!sr_semaphore.trywait(), "invalid semaphore state");
3016
3017 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
3018 // failed to switch to WAKEUP_REQUEST
3019 ShouldNotReachHere();
3020 return;
3021 }
3022
3023 while (true) {
3024 if (sr_notify(osthread) == 0) {
3025 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3026 if (osthread->sr.is_running()) {
3027 return;
3028 }
3029 }
3030 } else {
3031 ShouldNotReachHere();
3032 }
3033 }
3034
3035 guarantee(osthread->sr.is_running(), "Must be running!");
3036 }
3037
3038 ////////////////////////////////////////////////////////////////////////////////
3039 // interrupt support
3040
3041 void os::interrupt(Thread* thread) {
3042 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3043 "possibility of dangling Thread pointer");
3044
3045 OSThread* osthread = thread->osthread();
3046
3047 if (!osthread->interrupted()) {
3048 osthread->set_interrupted(true);
3049 // More than one thread can get here with the same value of osthread,
3050 // resulting in multiple notifications. We do, however, want the store
3051 // to interrupted() to be visible to other threads before we execute unpark().
3052 OrderAccess::fence();
3053 ParkEvent * const slp = thread->_SleepEvent ;
3054 if (slp != NULL) slp->unpark() ;
3055 }
3056
3057 // For JSR166. Unpark even if interrupt status already was set
3058 if (thread->is_Java_thread())
3059 ((JavaThread*)thread)->parker()->unpark();
3060
3061 ParkEvent * ev = thread->_ParkEvent ;
3062 if (ev != NULL) ev->unpark() ;
3063
3064 }
3065
3066 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3067 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3068 "possibility of dangling Thread pointer");
3069
3070 OSThread* osthread = thread->osthread();
3071
3072 bool interrupted = osthread->interrupted();
3073
3074 if (interrupted && clear_interrupted) {
3075 osthread->set_interrupted(false);
3076 // consider thread->_SleepEvent->reset() ... optional optimization
3077 }
3078
3079 return interrupted;
3080 }
3081
3082 ///////////////////////////////////////////////////////////////////////////////////
3083 // signal handling (except suspend/resume)
3084
3085 // This routine may be used by user applications as a "hook" to catch signals.
3086 // The user-defined signal handler must pass unrecognized signals to this
3087 // routine, and if it returns true (non-zero), then the signal handler must
3088 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3089 // routine will never retun false (zero), but instead will execute a VM panic
3090 // routine kill the process.
3091 //
3092 // If this routine returns false, it is OK to call it again. This allows
3093 // the user-defined signal handler to perform checks either before or after
3094 // the VM performs its own checks. Naturally, the user code would be making
3095 // a serious error if it tried to handle an exception (such as a null check
3096 // or breakpoint) that the VM was generating for its own correct operation.
3097 //
3098 // This routine may recognize any of the following kinds of signals:
3099 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3100 // It should be consulted by handlers for any of those signals.
3101 //
3102 // The caller of this routine must pass in the three arguments supplied
3103 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3104 // field of the structure passed to sigaction(). This routine assumes that
3105 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3106 //
3107 // Note that the VM will print warnings if it detects conflicting signal
3108 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3109 //
3110 extern "C" JNIEXPORT int
3111 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3112 void* ucontext, int abort_if_unrecognized);
3113
3114 void signalHandler(int sig, siginfo_t* info, void* uc) {
3115 assert(info != NULL && uc != NULL, "it must be old kernel");
3116 int orig_errno = errno; // Preserve errno value over signal handler.
3117 JVM_handle_bsd_signal(sig, info, uc, true);
3118 errno = orig_errno;
3119 }
3120
3121
3122 // This boolean allows users to forward their own non-matching signals
3123 // to JVM_handle_bsd_signal, harmlessly.
3124 bool os::Bsd::signal_handlers_are_installed = false;
3125
3126 // For signal-chaining
3127 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3128 unsigned int os::Bsd::sigs = 0;
3129 bool os::Bsd::libjsig_is_loaded = false;
3130 typedef struct sigaction *(*get_signal_t)(int);
3131 get_signal_t os::Bsd::get_signal_action = NULL;
3132
3133 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3134 struct sigaction *actp = NULL;
3135
3136 if (libjsig_is_loaded) {
3137 // Retrieve the old signal handler from libjsig
3138 actp = (*get_signal_action)(sig);
3139 }
3140 if (actp == NULL) {
3141 // Retrieve the preinstalled signal handler from jvm
3142 actp = get_preinstalled_handler(sig);
3143 }
3144
3145 return actp;
3146 }
3147
3148 static bool call_chained_handler(struct sigaction *actp, int sig,
3149 siginfo_t *siginfo, void *context) {
3150 // Call the old signal handler
3151 if (actp->sa_handler == SIG_DFL) {
3152 // It's more reasonable to let jvm treat it as an unexpected exception
3153 // instead of taking the default action.
3154 return false;
3155 } else if (actp->sa_handler != SIG_IGN) {
3156 if ((actp->sa_flags & SA_NODEFER) == 0) {
3157 // automaticlly block the signal
3158 sigaddset(&(actp->sa_mask), sig);
3159 }
3160
3161 sa_handler_t hand;
3162 sa_sigaction_t sa;
3163 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3164 // retrieve the chained handler
3165 if (siginfo_flag_set) {
3166 sa = actp->sa_sigaction;
3167 } else {
3168 hand = actp->sa_handler;
3169 }
3170
3171 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3172 actp->sa_handler = SIG_DFL;
3173 }
3174
3175 // try to honor the signal mask
3176 sigset_t oset;
3177 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3178
3179 // call into the chained handler
3180 if (siginfo_flag_set) {
3181 (*sa)(sig, siginfo, context);
3182 } else {
3183 (*hand)(sig);
3184 }
3185
3186 // restore the signal mask
3187 pthread_sigmask(SIG_SETMASK, &oset, 0);
3188 }
3189 // Tell jvm's signal handler the signal is taken care of.
3190 return true;
3191 }
3192
3193 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3194 bool chained = false;
3195 // signal-chaining
3196 if (UseSignalChaining) {
3197 struct sigaction *actp = get_chained_signal_action(sig);
3198 if (actp != NULL) {
3199 chained = call_chained_handler(actp, sig, siginfo, context);
3200 }
3201 }
3202 return chained;
3203 }
3204
3205 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3206 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3207 return &sigact[sig];
3208 }
3209 return NULL;
3210 }
3211
3212 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3213 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3214 sigact[sig] = oldAct;
3215 sigs |= (unsigned int)1 << sig;
3216 }
3217
3218 // for diagnostic
3219 int os::Bsd::sigflags[MAXSIGNUM];
3220
3221 int os::Bsd::get_our_sigflags(int sig) {
3222 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3223 return sigflags[sig];
3224 }
3225
3226 void os::Bsd::set_our_sigflags(int sig, int flags) {
3227 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3228 sigflags[sig] = flags;
3229 }
3230
3231 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3232 // Check for overwrite.
3233 struct sigaction oldAct;
3234 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3235
3236 void* oldhand = oldAct.sa_sigaction
3237 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3238 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3239 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3240 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3241 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3242 if (AllowUserSignalHandlers || !set_installed) {
3243 // Do not overwrite; user takes responsibility to forward to us.
3244 return;
3245 } else if (UseSignalChaining) {
3246 // save the old handler in jvm
3247 save_preinstalled_handler(sig, oldAct);
3248 // libjsig also interposes the sigaction() call below and saves the
3249 // old sigaction on it own.
3250 } else {
3251 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3252 "%#lx for signal %d.", (long)oldhand, sig));
3253 }
3254 }
3255
3256 struct sigaction sigAct;
3257 sigfillset(&(sigAct.sa_mask));
3258 sigAct.sa_handler = SIG_DFL;
3259 if (!set_installed) {
3260 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3261 } else {
3262 sigAct.sa_sigaction = signalHandler;
3263 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3264 }
3265 #ifdef __APPLE__
3266 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3267 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3268 // if the signal handler declares it will handle it on alternate stack.
3269 // Notice we only declare we will handle it on alt stack, but we are not
3270 // actually going to use real alt stack - this is just a workaround.
3271 // Please see ux_exception.c, method catch_mach_exception_raise for details
3272 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3273 if (sig == SIGSEGV) {
3274 sigAct.sa_flags |= SA_ONSTACK;
3275 }
3276 #endif
3277
3278 // Save flags, which are set by ours
3279 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3280 sigflags[sig] = sigAct.sa_flags;
3281
3282 int ret = sigaction(sig, &sigAct, &oldAct);
3283 assert(ret == 0, "check");
3284
3285 void* oldhand2 = oldAct.sa_sigaction
3286 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3287 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3288 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3289 }
3290
3291 // install signal handlers for signals that HotSpot needs to
3292 // handle in order to support Java-level exception handling.
3293
3294 void os::Bsd::install_signal_handlers() {
3295 if (!signal_handlers_are_installed) {
3296 signal_handlers_are_installed = true;
3297
3298 // signal-chaining
3299 typedef void (*signal_setting_t)();
3300 signal_setting_t begin_signal_setting = NULL;
3301 signal_setting_t end_signal_setting = NULL;
3302 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3303 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3304 if (begin_signal_setting != NULL) {
3305 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3306 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3307 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3308 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3309 libjsig_is_loaded = true;
3310 assert(UseSignalChaining, "should enable signal-chaining");
3311 }
3312 if (libjsig_is_loaded) {
3313 // Tell libjsig jvm is setting signal handlers
3314 (*begin_signal_setting)();
3315 }
3316
3317 set_signal_handler(SIGSEGV, true);
3318 set_signal_handler(SIGPIPE, true);
3319 set_signal_handler(SIGBUS, true);
3320 set_signal_handler(SIGILL, true);
3321 set_signal_handler(SIGFPE, true);
3322 set_signal_handler(SIGXFSZ, true);
3323
3324 #if defined(__APPLE__)
3325 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3326 // signals caught and handled by the JVM. To work around this, we reset the mach task
3327 // signal handler that's placed on our process by CrashReporter. This disables
3328 // CrashReporter-based reporting.
3329 //
3330 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3331 // on caught fatal signals.
3332 //
3333 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3334 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3335 // exception handling, while leaving the standard BSD signal handlers functional.
3336 kern_return_t kr;
3337 kr = task_set_exception_ports(mach_task_self(),
3338 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3339 MACH_PORT_NULL,
3340 EXCEPTION_STATE_IDENTITY,
3341 MACHINE_THREAD_STATE);
3342
3343 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3344 #endif
3345
3346 if (libjsig_is_loaded) {
3347 // Tell libjsig jvm finishes setting signal handlers
3348 (*end_signal_setting)();
3349 }
3350
3351 // We don't activate signal checker if libjsig is in place, we trust ourselves
3352 // and if UserSignalHandler is installed all bets are off
3353 if (CheckJNICalls) {
3354 if (libjsig_is_loaded) {
3355 if (PrintJNIResolving) {
3356 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3357 }
3358 check_signals = false;
3359 }
3360 if (AllowUserSignalHandlers) {
3361 if (PrintJNIResolving) {
3362 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3363 }
3364 check_signals = false;
3365 }
3366 }
3367 }
3368 }
3369
3370
3371 /////
3372 // glibc on Bsd platform uses non-documented flag
3373 // to indicate, that some special sort of signal
3374 // trampoline is used.
3375 // We will never set this flag, and we should
3376 // ignore this flag in our diagnostic
3377 #ifdef SIGNIFICANT_SIGNAL_MASK
3378 #undef SIGNIFICANT_SIGNAL_MASK
3379 #endif
3380 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3381
3382 static const char* get_signal_handler_name(address handler,
3383 char* buf, int buflen) {
3384 int offset;
3385 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3386 if (found) {
3387 // skip directory names
3388 const char *p1, *p2;
3389 p1 = buf;
3390 size_t len = strlen(os::file_separator());
3391 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3392 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3393 } else {
3394 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3395 }
3396 return buf;
3397 }
3398
3399 static void print_signal_handler(outputStream* st, int sig,
3400 char* buf, size_t buflen) {
3401 struct sigaction sa;
3402
3403 sigaction(sig, NULL, &sa);
3404
3405 // See comment for SIGNIFICANT_SIGNAL_MASK define
3406 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3407
3408 st->print("%s: ", os::exception_name(sig, buf, buflen));
3409
3410 address handler = (sa.sa_flags & SA_SIGINFO)
3411 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3412 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3413
3414 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3415 st->print("SIG_DFL");
3416 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3417 st->print("SIG_IGN");
3418 } else {
3419 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3420 }
3421
3422 st->print(", sa_mask[0]=");
3423 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3424
3425 address rh = VMError::get_resetted_sighandler(sig);
3426 // May be, handler was resetted by VMError?
3427 if(rh != NULL) {
3428 handler = rh;
3429 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3430 }
3431
3432 st->print(", sa_flags=");
3433 os::Posix::print_sa_flags(st, sa.sa_flags);
3434
3435 // Check: is it our handler?
3436 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3437 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3438 // It is our signal handler
3439 // check for flags, reset system-used one!
3440 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3441 st->print(
3442 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3443 os::Bsd::get_our_sigflags(sig));
3444 }
3445 }
3446 st->cr();
3447 }
3448
3449
3450 #define DO_SIGNAL_CHECK(sig) \
3451 if (!sigismember(&check_signal_done, sig)) \
3452 os::Bsd::check_signal_handler(sig)
3453
3454 // This method is a periodic task to check for misbehaving JNI applications
3455 // under CheckJNI, we can add any periodic checks here
3456
3457 void os::run_periodic_checks() {
3458
3459 if (check_signals == false) return;
3460
3461 // SEGV and BUS if overridden could potentially prevent
3462 // generation of hs*.log in the event of a crash, debugging
3463 // such a case can be very challenging, so we absolutely
3464 // check the following for a good measure:
3465 DO_SIGNAL_CHECK(SIGSEGV);
3466 DO_SIGNAL_CHECK(SIGILL);
3467 DO_SIGNAL_CHECK(SIGFPE);
3468 DO_SIGNAL_CHECK(SIGBUS);
3469 DO_SIGNAL_CHECK(SIGPIPE);
3470 DO_SIGNAL_CHECK(SIGXFSZ);
3471
3472
3473 // ReduceSignalUsage allows the user to override these handlers
3474 // see comments at the very top and jvm_solaris.h
3475 if (!ReduceSignalUsage) {
3476 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3477 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3478 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3479 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3480 }
3481
3482 DO_SIGNAL_CHECK(SR_signum);
3483 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3484 }
3485
3486 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3487
3488 static os_sigaction_t os_sigaction = NULL;
3489
3490 void os::Bsd::check_signal_handler(int sig) {
3491 char buf[O_BUFLEN];
3492 address jvmHandler = NULL;
3493
3494
3495 struct sigaction act;
3496 if (os_sigaction == NULL) {
3497 // only trust the default sigaction, in case it has been interposed
3498 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3499 if (os_sigaction == NULL) return;
3500 }
3501
3502 os_sigaction(sig, (struct sigaction*)NULL, &act);
3503
3504
3505 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3506
3507 address thisHandler = (act.sa_flags & SA_SIGINFO)
3508 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3509 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3510
3511
3512 switch(sig) {
3513 case SIGSEGV:
3514 case SIGBUS:
3515 case SIGFPE:
3516 case SIGPIPE:
3517 case SIGILL:
3518 case SIGXFSZ:
3519 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3520 break;
3521
3522 case SHUTDOWN1_SIGNAL:
3523 case SHUTDOWN2_SIGNAL:
3524 case SHUTDOWN3_SIGNAL:
3525 case BREAK_SIGNAL:
3526 jvmHandler = (address)user_handler();
3527 break;
3528
3529 case INTERRUPT_SIGNAL:
3530 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3531 break;
3532
3533 default:
3534 if (sig == SR_signum) {
3535 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3536 } else {
3537 return;
3538 }
3539 break;
3540 }
3541
3542 if (thisHandler != jvmHandler) {
3543 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3544 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3545 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3546 // No need to check this sig any longer
3547 sigaddset(&check_signal_done, sig);
3548 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3549 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3550 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3551 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3552 // No need to check this sig any longer
3553 sigaddset(&check_signal_done, sig);
3554 }
3555
3556 // Dump all the signal
3557 if (sigismember(&check_signal_done, sig)) {
3558 print_signal_handlers(tty, buf, O_BUFLEN);
3559 }
3560 }
3561
3562 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3563
3564 extern bool signal_name(int signo, char* buf, size_t len);
3565
3566 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3567 if (0 < exception_code && exception_code <= SIGRTMAX) {
3568 // signal
3569 if (!signal_name(exception_code, buf, size)) {
3570 jio_snprintf(buf, size, "SIG%d", exception_code);
3571 }
3572 return buf;
3573 } else {
3574 return NULL;
3575 }
3576 }
3577
3578 // this is called _before_ the most of global arguments have been parsed
3579 void os::init(void) {
3580 char dummy; /* used to get a guess on initial stack address */
3581 // first_hrtime = gethrtime();
3582
3583 // With BsdThreads the JavaMain thread pid (primordial thread)
3584 // is different than the pid of the java launcher thread.
3585 // So, on Bsd, the launcher thread pid is passed to the VM
3586 // via the sun.java.launcher.pid property.
3587 // Use this property instead of getpid() if it was correctly passed.
3588 // See bug 6351349.
3589 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3590
3591 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3592
3593 clock_tics_per_sec = CLK_TCK;
3594
3595 init_random(1234567);
3596
3597 ThreadCritical::initialize();
3598
3599 Bsd::set_page_size(getpagesize());
3600 if (Bsd::page_size() == -1) {
3601 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3602 strerror(errno)));
3603 }
3604 init_page_sizes((size_t) Bsd::page_size());
3605
3606 Bsd::initialize_system_info();
3607
3608 // main_thread points to the aboriginal thread
3609 Bsd::_main_thread = pthread_self();
3610
3611 Bsd::clock_init();
3612 initial_time_count = javaTimeNanos();
3613
3614 #ifdef __APPLE__
3615 // XXXDARWIN
3616 // Work around the unaligned VM callbacks in hotspot's
3617 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3618 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3619 // alignment when doing symbol lookup. To work around this, we force early
3620 // binding of all symbols now, thus binding when alignment is known-good.
3621 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3622 #endif
3623 }
3624
3625 // To install functions for atexit system call
3626 extern "C" {
3627 static void perfMemory_exit_helper() {
3628 perfMemory_exit();
3629 }
3630 }
3631
3632 // this is called _after_ the global arguments have been parsed
3633 jint os::init_2(void)
3634 {
3635 // Allocate a single page and mark it as readable for safepoint polling
3636 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3637 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3638
3639 os::set_polling_page( polling_page );
3640
3641 #ifndef PRODUCT
3642 if(Verbose && PrintMiscellaneous)
3643 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3644 #endif
3645
3646 if (!UseMembar) {
3647 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3648 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3649 os::set_memory_serialize_page( mem_serialize_page );
3650
3651 #ifndef PRODUCT
3652 if(Verbose && PrintMiscellaneous)
3653 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3654 #endif
3655 }
3656
3657 // initialize suspend/resume support - must do this before signal_sets_init()
3658 if (SR_initialize() != 0) {
3659 perror("SR_initialize failed");
3660 return JNI_ERR;
3661 }
3662
3663 Bsd::signal_sets_init();
3664 Bsd::install_signal_handlers();
3665
3666 // Check minimum allowable stack size for thread creation and to initialize
3667 // the java system classes, including StackOverflowError - depends on page
3668 // size. Add a page for compiler2 recursion in main thread.
3669 // Add in 2*BytesPerWord times page size to account for VM stack during
3670 // class initialization depending on 32 or 64 bit VM.
3671 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3672 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3673 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3674
3675 size_t threadStackSizeInBytes = ThreadStackSize * K;
3676 if (threadStackSizeInBytes != 0 &&
3677 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3678 tty->print_cr("\nThe stack size specified is too small, "
3679 "Specify at least %dk",
3680 os::Bsd::min_stack_allowed/ K);
3681 return JNI_ERR;
3682 }
3683
3684 // Make the stack size a multiple of the page size so that
3685 // the yellow/red zones can be guarded.
3686 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3687 vm_page_size()));
3688
3689 if (MaxFDLimit) {
3690 // set the number of file descriptors to max. print out error
3691 // if getrlimit/setrlimit fails but continue regardless.
3692 struct rlimit nbr_files;
3693 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3694 if (status != 0) {
3695 if (PrintMiscellaneous && (Verbose || WizardMode))
3696 perror("os::init_2 getrlimit failed");
3697 } else {
3698 nbr_files.rlim_cur = nbr_files.rlim_max;
3699
3700 #ifdef __APPLE__
3701 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3702 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3703 // be used instead
3704 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3705 #endif
3706
3707 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3708 if (status != 0) {
3709 if (PrintMiscellaneous && (Verbose || WizardMode))
3710 perror("os::init_2 setrlimit failed");
3711 }
3712 }
3713 }
3714
3715 // at-exit methods are called in the reverse order of their registration.
3716 // atexit functions are called on return from main or as a result of a
3717 // call to exit(3C). There can be only 32 of these functions registered
3718 // and atexit() does not set errno.
3719
3720 if (PerfAllowAtExitRegistration) {
3721 // only register atexit functions if PerfAllowAtExitRegistration is set.
3722 // atexit functions can be delayed until process exit time, which
3723 // can be problematic for embedded VM situations. Embedded VMs should
3724 // call DestroyJavaVM() to assure that VM resources are released.
3725
3726 // note: perfMemory_exit_helper atexit function may be removed in
3727 // the future if the appropriate cleanup code can be added to the
3728 // VM_Exit VMOperation's doit method.
3729 if (atexit(perfMemory_exit_helper) != 0) {
3730 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3731 }
3732 }
3733
3734 // initialize thread priority policy
3735 prio_init();
3736
3737 #ifdef __APPLE__
3738 // dynamically link to objective c gc registration
3739 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3740 if (handleLibObjc != NULL) {
3741 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3742 }
3743 #endif
3744
3745 return JNI_OK;
3746 }
3747
3748 // Mark the polling page as unreadable
3749 void os::make_polling_page_unreadable(void) {
3750 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3751 fatal("Could not disable polling page");
3752 };
3753
3754 // Mark the polling page as readable
3755 void os::make_polling_page_readable(void) {
3756 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3757 fatal("Could not enable polling page");
3758 }
3759 };
3760
3761 int os::active_processor_count() {
3762 return _processor_count;
3763 }
3764
3765 void os::set_native_thread_name(const char *name) {
3766 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3767 // This is only supported in Snow Leopard and beyond
3768 if (name != NULL) {
3769 // Add a "Java: " prefix to the name
3770 char buf[MAXTHREADNAMESIZE];
3771 snprintf(buf, sizeof(buf), "Java: %s", name);
3772 pthread_setname_np(buf);
3773 }
3774 #endif
3775 }
3776
3777 bool os::distribute_processes(uint length, uint* distribution) {
3778 // Not yet implemented.
3779 return false;
3780 }
3781
3782 bool os::bind_to_processor(uint processor_id) {
3783 // Not yet implemented.
3784 return false;
3785 }
3786
3787 void os::SuspendedThreadTask::internal_do_task() {
3788 if (do_suspend(_thread->osthread())) {
3789 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3790 do_task(context);
3791 do_resume(_thread->osthread());
3792 }
3793 }
3794
3795 ///
3796 class PcFetcher : public os::SuspendedThreadTask {
3797 public:
3798 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3799 ExtendedPC result();
3800 protected:
3801 void do_task(const os::SuspendedThreadTaskContext& context);
3802 private:
3803 ExtendedPC _epc;
3804 };
3805
3806 ExtendedPC PcFetcher::result() {
3807 guarantee(is_done(), "task is not done yet.");
3808 return _epc;
3809 }
3810
3811 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3812 Thread* thread = context.thread();
3813 OSThread* osthread = thread->osthread();
3814 if (osthread->ucontext() != NULL) {
3815 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3816 } else {
3817 // NULL context is unexpected, double-check this is the VMThread
3818 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3819 }
3820 }
3821
3822 // Suspends the target using the signal mechanism and then grabs the PC before
3823 // resuming the target. Used by the flat-profiler only
3824 ExtendedPC os::get_thread_pc(Thread* thread) {
3825 // Make sure that it is called by the watcher for the VMThread
3826 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3827 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3828
3829 PcFetcher fetcher(thread);
3830 fetcher.run();
3831 return fetcher.result();
3832 }
3833
3834 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3835 {
3836 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3837 }
3838
3839 ////////////////////////////////////////////////////////////////////////////////
3840 // debug support
3841
3842 bool os::find(address addr, outputStream* st) {
3843 Dl_info dlinfo;
3844 memset(&dlinfo, 0, sizeof(dlinfo));
3845 if (dladdr(addr, &dlinfo) != 0) {
3846 st->print(PTR_FORMAT ": ", addr);
3847 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3848 st->print("%s+%#x", dlinfo.dli_sname,
3849 addr - (intptr_t)dlinfo.dli_saddr);
3850 } else if (dlinfo.dli_fbase != NULL) {
3851 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3852 } else {
3853 st->print("<absolute address>");
3854 }
3855 if (dlinfo.dli_fname != NULL) {
3856 st->print(" in %s", dlinfo.dli_fname);
3857 }
3858 if (dlinfo.dli_fbase != NULL) {
3859 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3860 }
3861 st->cr();
3862
3863 if (Verbose) {
3864 // decode some bytes around the PC
3865 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3866 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3867 address lowest = (address) dlinfo.dli_sname;
3868 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3869 if (begin < lowest) begin = lowest;
3870 Dl_info dlinfo2;
3871 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3872 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3873 end = (address) dlinfo2.dli_saddr;
3874 Disassembler::decode(begin, end, st);
3875 }
3876 return true;
3877 }
3878 return false;
3879 }
3880
3881 ////////////////////////////////////////////////////////////////////////////////
3882 // misc
3883
3884 // This does not do anything on Bsd. This is basically a hook for being
3885 // able to use structured exception handling (thread-local exception filters)
3886 // on, e.g., Win32.
3887 void
3888 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3889 JavaCallArguments* args, Thread* thread) {
3890 f(value, method, args, thread);
3891 }
3892
3893 void os::print_statistics() {
3894 }
3895
3896 int os::message_box(const char* title, const char* message) {
3897 int i;
3898 fdStream err(defaultStream::error_fd());
3899 for (i = 0; i < 78; i++) err.print_raw("=");
3900 err.cr();
3901 err.print_raw_cr(title);
3902 for (i = 0; i < 78; i++) err.print_raw("-");
3903 err.cr();
3904 err.print_raw_cr(message);
3905 for (i = 0; i < 78; i++) err.print_raw("=");
3906 err.cr();
3907
3908 char buf[16];
3909 // Prevent process from exiting upon "read error" without consuming all CPU
3910 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3911
3912 return buf[0] == 'y' || buf[0] == 'Y';
3913 }
3914
3915 int os::stat(const char *path, struct stat *sbuf) {
3916 char pathbuf[MAX_PATH];
3917 if (strlen(path) > MAX_PATH - 1) {
3918 errno = ENAMETOOLONG;
3919 return -1;
3920 }
3921 os::native_path(strcpy(pathbuf, path));
3922 return ::stat(pathbuf, sbuf);
3923 }
3924
3925 bool os::check_heap(bool force) {
3926 return true;
3927 }
3928
3929 ATTRIBUTE_PRINTF(3, 0)
3930 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3931 return ::vsnprintf(buf, count, format, args);
3932 }
3933
3934 // Is a (classpath) directory empty?
3935 bool os::dir_is_empty(const char* path) {
3936 DIR *dir = NULL;
3937 struct dirent *ptr;
3938
3939 dir = opendir(path);
3940 if (dir == NULL) return true;
3941
3942 /* Scan the directory */
3943 bool result = true;
3944 char buf[sizeof(struct dirent) + MAX_PATH];
3945 while (result && (ptr = ::readdir(dir)) != NULL) {
3946 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3947 result = false;
3948 }
3949 }
3950 closedir(dir);
3951 return result;
3952 }
3953
3954 // This code originates from JDK's sysOpen and open64_w
3955 // from src/solaris/hpi/src/system_md.c
3956
3957 #ifndef O_DELETE
3958 #define O_DELETE 0x10000
3959 #endif
3960
3961 // Open a file. Unlink the file immediately after open returns
3962 // if the specified oflag has the O_DELETE flag set.
3963 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3964
3965 int os::open(const char *path, int oflag, int mode) {
3966
3967 if (strlen(path) > MAX_PATH - 1) {
3968 errno = ENAMETOOLONG;
3969 return -1;
3970 }
3971 int fd;
3972 int o_delete = (oflag & O_DELETE);
3973 oflag = oflag & ~O_DELETE;
3974
3975 fd = ::open(path, oflag, mode);
3976 if (fd == -1) return -1;
3977
3978 //If the open succeeded, the file might still be a directory
3979 {
3980 struct stat buf;
3981 int ret = ::fstat(fd, &buf);
3982 int st_mode = buf.st_mode;
3983
3984 if (ret != -1) {
3985 if ((st_mode & S_IFMT) == S_IFDIR) {
3986 errno = EISDIR;
3987 ::close(fd);
3988 return -1;
3989 }
3990 } else {
3991 ::close(fd);
3992 return -1;
3993 }
3994 }
3995
3996 /*
3997 * All file descriptors that are opened in the JVM and not
3998 * specifically destined for a subprocess should have the
3999 * close-on-exec flag set. If we don't set it, then careless 3rd
4000 * party native code might fork and exec without closing all
4001 * appropriate file descriptors (e.g. as we do in closeDescriptors in
4002 * UNIXProcess.c), and this in turn might:
4003 *
4004 * - cause end-of-file to fail to be detected on some file
4005 * descriptors, resulting in mysterious hangs, or
4006 *
4007 * - might cause an fopen in the subprocess to fail on a system
4008 * suffering from bug 1085341.
4009 *
4010 * (Yes, the default setting of the close-on-exec flag is a Unix
4011 * design flaw)
4012 *
4013 * See:
4014 * 1085341: 32-bit stdio routines should support file descriptors >255
4015 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4016 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4017 */
4018 #ifdef FD_CLOEXEC
4019 {
4020 int flags = ::fcntl(fd, F_GETFD);
4021 if (flags != -1)
4022 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4023 }
4024 #endif
4025
4026 if (o_delete != 0) {
4027 ::unlink(path);
4028 }
4029 return fd;
4030 }
4031
4032
4033 // create binary file, rewriting existing file if required
4034 int os::create_binary_file(const char* path, bool rewrite_existing) {
4035 int oflags = O_WRONLY | O_CREAT;
4036 if (!rewrite_existing) {
4037 oflags |= O_EXCL;
4038 }
4039 return ::open(path, oflags, S_IREAD | S_IWRITE);
4040 }
4041
4042 // return current position of file pointer
4043 jlong os::current_file_offset(int fd) {
4044 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4045 }
4046
4047 // move file pointer to the specified offset
4048 jlong os::seek_to_file_offset(int fd, jlong offset) {
4049 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4050 }
4051
4052 // This code originates from JDK's sysAvailable
4053 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4054
4055 int os::available(int fd, jlong *bytes) {
4056 jlong cur, end;
4057 int mode;
4058 struct stat buf;
4059
4060 if (::fstat(fd, &buf) >= 0) {
4061 mode = buf.st_mode;
4062 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4063 /*
4064 * XXX: is the following call interruptible? If so, this might
4065 * need to go through the INTERRUPT_IO() wrapper as for other
4066 * blocking, interruptible calls in this file.
4067 */
4068 int n;
4069 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4070 *bytes = n;
4071 return 1;
4072 }
4073 }
4074 }
4075 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4076 return 0;
4077 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4078 return 0;
4079 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4080 return 0;
4081 }
4082 *bytes = end - cur;
4083 return 1;
4084 }
4085
4086 int os::socket_available(int fd, jint *pbytes) {
4087 if (fd < 0)
4088 return OS_OK;
4089
4090 int ret;
4091
4092 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4093
4094 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4095 // is expected to return 0 on failure and 1 on success to the jdk.
4096
4097 return (ret == OS_ERR) ? 0 : 1;
4098 }
4099
4100 // Map a block of memory.
4101 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4102 char *addr, size_t bytes, bool read_only,
4103 bool allow_exec) {
4104 int prot;
4105 int flags;
4106
4107 if (read_only) {
4108 prot = PROT_READ;
4109 flags = MAP_SHARED;
4110 } else {
4111 prot = PROT_READ | PROT_WRITE;
4112 flags = MAP_PRIVATE;
4113 }
4114
4115 if (allow_exec) {
4116 prot |= PROT_EXEC;
4117 }
4118
4119 if (addr != NULL) {
4120 flags |= MAP_FIXED;
4121 }
4122
4123 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4124 fd, file_offset);
4125 if (mapped_address == MAP_FAILED) {
4126 return NULL;
4127 }
4128 return mapped_address;
4129 }
4130
4131
4132 // Remap a block of memory.
4133 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4134 char *addr, size_t bytes, bool read_only,
4135 bool allow_exec) {
4136 // same as map_memory() on this OS
4137 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4138 allow_exec);
4139 }
4140
4141
4142 // Unmap a block of memory.
4143 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4144 return munmap(addr, bytes) == 0;
4145 }
4146
4147 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4148 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4149 // of a thread.
4150 //
4151 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4152 // the fast estimate available on the platform.
4153
4154 jlong os::current_thread_cpu_time() {
4155 #ifdef __APPLE__
4156 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4157 #else
4158 Unimplemented();
4159 return 0;
4160 #endif
4161 }
4162
4163 jlong os::thread_cpu_time(Thread* thread) {
4164 #ifdef __APPLE__
4165 return os::thread_cpu_time(thread, true /* user + sys */);
4166 #else
4167 Unimplemented();
4168 return 0;
4169 #endif
4170 }
4171
4172 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4173 #ifdef __APPLE__
4174 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4175 #else
4176 Unimplemented();
4177 return 0;
4178 #endif
4179 }
4180
4181 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4182 #ifdef __APPLE__
4183 struct thread_basic_info tinfo;
4184 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4185 kern_return_t kr;
4186 thread_t mach_thread;
4187
4188 mach_thread = thread->osthread()->thread_id();
4189 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4190 if (kr != KERN_SUCCESS)
4191 return -1;
4192
4193 if (user_sys_cpu_time) {
4194 jlong nanos;
4195 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4196 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4197 return nanos;
4198 } else {
4199 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4200 }
4201 #else
4202 Unimplemented();
4203 return 0;
4204 #endif
4205 }
4206
4207
4208 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4209 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4210 info_ptr->may_skip_backward = false; // elapsed time not wall time
4211 info_ptr->may_skip_forward = false; // elapsed time not wall time
4212 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4213 }
4214
4215 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4216 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4217 info_ptr->may_skip_backward = false; // elapsed time not wall time
4218 info_ptr->may_skip_forward = false; // elapsed time not wall time
4219 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4220 }
4221
4222 bool os::is_thread_cpu_time_supported() {
4223 #ifdef __APPLE__
4224 return true;
4225 #else
4226 return false;
4227 #endif
4228 }
4229
4230 // System loadavg support. Returns -1 if load average cannot be obtained.
4231 // Bsd doesn't yet have a (official) notion of processor sets,
4232 // so just return the system wide load average.
4233 int os::loadavg(double loadavg[], int nelem) {
4234 return ::getloadavg(loadavg, nelem);
4235 }
4236
4237 void os::pause() {
4238 char filename[MAX_PATH];
4239 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4240 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4241 } else {
4242 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4243 }
4244
4245 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4246 if (fd != -1) {
4247 struct stat buf;
4248 ::close(fd);
4249 while (::stat(filename, &buf) == 0) {
4250 (void)::poll(NULL, 0, 100);
4251 }
4252 } else {
4253 jio_fprintf(stderr,
4254 "Could not open pause file '%s', continuing immediately.\n", filename);
4255 }
4256 }
4257
4258
4259 // Refer to the comments in os_solaris.cpp park-unpark.
4260 //
4261 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4262 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4263 // For specifics regarding the bug see GLIBC BUGID 261237 :
4264 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4265 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4266 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4267 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4268 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4269 // and monitorenter when we're using 1-0 locking. All those operations may result in
4270 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4271 // of libpthread avoids the problem, but isn't practical.
4272 //
4273 // Possible remedies:
4274 //
4275 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4276 // This is palliative and probabilistic, however. If the thread is preempted
4277 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4278 // than the minimum period may have passed, and the abstime may be stale (in the
4279 // past) resultin in a hang. Using this technique reduces the odds of a hang
4280 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4281 //
4282 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4283 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4284 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4285 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4286 // thread.
4287 //
4288 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4289 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4290 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4291 // This also works well. In fact it avoids kernel-level scalability impediments
4292 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4293 // timers in a graceful fashion.
4294 //
4295 // 4. When the abstime value is in the past it appears that control returns
4296 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4297 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4298 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4299 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4300 // It may be possible to avoid reinitialization by checking the return
4301 // value from pthread_cond_timedwait(). In addition to reinitializing the
4302 // condvar we must establish the invariant that cond_signal() is only called
4303 // within critical sections protected by the adjunct mutex. This prevents
4304 // cond_signal() from "seeing" a condvar that's in the midst of being
4305 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4306 // desirable signal-after-unlock optimization that avoids futile context switching.
4307 //
4308 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4309 // structure when a condvar is used or initialized. cond_destroy() would
4310 // release the helper structure. Our reinitialize-after-timedwait fix
4311 // put excessive stress on malloc/free and locks protecting the c-heap.
4312 //
4313 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4314 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4315 // and only enabling the work-around for vulnerable environments.
4316
4317 // utility to compute the abstime argument to timedwait:
4318 // millis is the relative timeout time
4319 // abstime will be the absolute timeout time
4320 // TODO: replace compute_abstime() with unpackTime()
4321
4322 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4323 if (millis < 0) millis = 0;
4324 struct timeval now;
4325 int status = gettimeofday(&now, NULL);
4326 assert(status == 0, "gettimeofday");
4327 jlong seconds = millis / 1000;
4328 millis %= 1000;
4329 if (seconds > 50000000) { // see man cond_timedwait(3T)
4330 seconds = 50000000;
4331 }
4332 abstime->tv_sec = now.tv_sec + seconds;
4333 long usec = now.tv_usec + millis * 1000;
4334 if (usec >= 1000000) {
4335 abstime->tv_sec += 1;
4336 usec -= 1000000;
4337 }
4338 abstime->tv_nsec = usec * 1000;
4339 return abstime;
4340 }
4341
4342
4343 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4344 // Conceptually TryPark() should be equivalent to park(0).
4345
4346 int os::PlatformEvent::TryPark() {
4347 for (;;) {
4348 const int v = _Event ;
4349 guarantee ((v == 0) || (v == 1), "invariant") ;
4350 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4351 }
4352 }
4353
4354 void os::PlatformEvent::park() { // AKA "down()"
4355 // Invariant: Only the thread associated with the Event/PlatformEvent
4356 // may call park().
4357 // TODO: assert that _Assoc != NULL or _Assoc == Self
4358 int v ;
4359 for (;;) {
4360 v = _Event ;
4361 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4362 }
4363 guarantee (v >= 0, "invariant") ;
4364 if (v == 0) {
4365 // Do this the hard way by blocking ...
4366 int status = pthread_mutex_lock(_mutex);
4367 assert_status(status == 0, status, "mutex_lock");
4368 guarantee (_nParked == 0, "invariant") ;
4369 ++ _nParked ;
4370 while (_Event < 0) {
4371 status = pthread_cond_wait(_cond, _mutex);
4372 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4373 // Treat this the same as if the wait was interrupted
4374 if (status == ETIMEDOUT) { status = EINTR; }
4375 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4376 }
4377 -- _nParked ;
4378
4379 _Event = 0 ;
4380 status = pthread_mutex_unlock(_mutex);
4381 assert_status(status == 0, status, "mutex_unlock");
4382 // Paranoia to ensure our locked and lock-free paths interact
4383 // correctly with each other.
4384 OrderAccess::fence();
4385 }
4386 guarantee (_Event >= 0, "invariant") ;
4387 }
4388
4389 int os::PlatformEvent::park(jlong millis) {
4390 guarantee (_nParked == 0, "invariant") ;
4391
4392 int v ;
4393 for (;;) {
4394 v = _Event ;
4395 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4396 }
4397 guarantee (v >= 0, "invariant") ;
4398 if (v != 0) return OS_OK ;
4399
4400 // We do this the hard way, by blocking the thread.
4401 // Consider enforcing a minimum timeout value.
4402 struct timespec abst;
4403 compute_abstime(&abst, millis);
4404
4405 int ret = OS_TIMEOUT;
4406 int status = pthread_mutex_lock(_mutex);
4407 assert_status(status == 0, status, "mutex_lock");
4408 guarantee (_nParked == 0, "invariant") ;
4409 ++_nParked ;
4410
4411 // Object.wait(timo) will return because of
4412 // (a) notification
4413 // (b) timeout
4414 // (c) thread.interrupt
4415 //
4416 // Thread.interrupt and object.notify{All} both call Event::set.
4417 // That is, we treat thread.interrupt as a special case of notification.
4418 // The underlying Solaris implementation, cond_timedwait, admits
4419 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4420 // JVM from making those visible to Java code. As such, we must
4421 // filter out spurious wakeups. We assume all ETIME returns are valid.
4422 //
4423 // TODO: properly differentiate simultaneous notify+interrupt.
4424 // In that case, we should propagate the notify to another waiter.
4425
4426 while (_Event < 0) {
4427 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4428 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4429 pthread_cond_destroy (_cond);
4430 pthread_cond_init (_cond, NULL) ;
4431 }
4432 assert_status(status == 0 || status == EINTR ||
4433 status == ETIMEDOUT,
4434 status, "cond_timedwait");
4435 if (!FilterSpuriousWakeups) break ; // previous semantics
4436 if (status == ETIMEDOUT) break ;
4437 // We consume and ignore EINTR and spurious wakeups.
4438 }
4439 --_nParked ;
4440 if (_Event >= 0) {
4441 ret = OS_OK;
4442 }
4443 _Event = 0 ;
4444 status = pthread_mutex_unlock(_mutex);
4445 assert_status(status == 0, status, "mutex_unlock");
4446 assert (_nParked == 0, "invariant") ;
4447 // Paranoia to ensure our locked and lock-free paths interact
4448 // correctly with each other.
4449 OrderAccess::fence();
4450 return ret;
4451 }
4452
4453 void os::PlatformEvent::unpark() {
4454 // Transitions for _Event:
4455 // 0 :=> 1
4456 // 1 :=> 1
4457 // -1 :=> either 0 or 1; must signal target thread
4458 // That is, we can safely transition _Event from -1 to either
4459 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4460 // unpark() calls.
4461 // See also: "Semaphores in Plan 9" by Mullender & Cox
4462 //
4463 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4464 // that it will take two back-to-back park() calls for the owning
4465 // thread to block. This has the benefit of forcing a spurious return
4466 // from the first park() call after an unpark() call which will help
4467 // shake out uses of park() and unpark() without condition variables.
4468
4469 if (Atomic::xchg(1, &_Event) >= 0) return;
4470
4471 // Wait for the thread associated with the event to vacate
4472 int status = pthread_mutex_lock(_mutex);
4473 assert_status(status == 0, status, "mutex_lock");
4474 int AnyWaiters = _nParked;
4475 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4476 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4477 AnyWaiters = 0;
4478 pthread_cond_signal(_cond);
4479 }
4480 status = pthread_mutex_unlock(_mutex);
4481 assert_status(status == 0, status, "mutex_unlock");
4482 if (AnyWaiters != 0) {
4483 status = pthread_cond_signal(_cond);
4484 assert_status(status == 0, status, "cond_signal");
4485 }
4486
4487 // Note that we signal() _after dropping the lock for "immortal" Events.
4488 // This is safe and avoids a common class of futile wakeups. In rare
4489 // circumstances this can cause a thread to return prematurely from
4490 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4491 // simply re-test the condition and re-park itself.
4492 }
4493
4494
4495 // JSR166
4496 // -------------------------------------------------------
4497
4498 /*
4499 * The solaris and bsd implementations of park/unpark are fairly
4500 * conservative for now, but can be improved. They currently use a
4501 * mutex/condvar pair, plus a a count.
4502 * Park decrements count if > 0, else does a condvar wait. Unpark
4503 * sets count to 1 and signals condvar. Only one thread ever waits
4504 * on the condvar. Contention seen when trying to park implies that someone
4505 * is unparking you, so don't wait. And spurious returns are fine, so there
4506 * is no need to track notifications.
4507 */
4508
4509 #define MAX_SECS 100000000
4510 /*
4511 * This code is common to bsd and solaris and will be moved to a
4512 * common place in dolphin.
4513 *
4514 * The passed in time value is either a relative time in nanoseconds
4515 * or an absolute time in milliseconds. Either way it has to be unpacked
4516 * into suitable seconds and nanoseconds components and stored in the
4517 * given timespec structure.
4518 * Given time is a 64-bit value and the time_t used in the timespec is only
4519 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4520 * overflow if times way in the future are given. Further on Solaris versions
4521 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4522 * number of seconds, in abstime, is less than current_time + 100,000,000.
4523 * As it will be 28 years before "now + 100000000" will overflow we can
4524 * ignore overflow and just impose a hard-limit on seconds using the value
4525 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4526 * years from "now".
4527 */
4528
4529 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4530 assert (time > 0, "convertTime");
4531
4532 struct timeval now;
4533 int status = gettimeofday(&now, NULL);
4534 assert(status == 0, "gettimeofday");
4535
4536 time_t max_secs = now.tv_sec + MAX_SECS;
4537
4538 if (isAbsolute) {
4539 jlong secs = time / 1000;
4540 if (secs > max_secs) {
4541 absTime->tv_sec = max_secs;
4542 }
4543 else {
4544 absTime->tv_sec = secs;
4545 }
4546 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4547 }
4548 else {
4549 jlong secs = time / NANOSECS_PER_SEC;
4550 if (secs >= MAX_SECS) {
4551 absTime->tv_sec = max_secs;
4552 absTime->tv_nsec = 0;
4553 }
4554 else {
4555 absTime->tv_sec = now.tv_sec + secs;
4556 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4557 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4558 absTime->tv_nsec -= NANOSECS_PER_SEC;
4559 ++absTime->tv_sec; // note: this must be <= max_secs
4560 }
4561 }
4562 }
4563 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4564 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4565 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4566 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4567 }
4568
4569 void Parker::park(bool isAbsolute, jlong time) {
4570 // Ideally we'd do something useful while spinning, such
4571 // as calling unpackTime().
4572
4573 // Optional fast-path check:
4574 // Return immediately if a permit is available.
4575 // We depend on Atomic::xchg() having full barrier semantics
4576 // since we are doing a lock-free update to _counter.
4577 if (Atomic::xchg(0, &_counter) > 0) return;
4578
4579 Thread* thread = Thread::current();
4580 assert(thread->is_Java_thread(), "Must be JavaThread");
4581 JavaThread *jt = (JavaThread *)thread;
4582
4583 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4584 // Check interrupt before trying to wait
4585 if (Thread::is_interrupted(thread, false)) {
4586 return;
4587 }
4588
4589 // Next, demultiplex/decode time arguments
4590 struct timespec absTime;
4591 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4592 return;
4593 }
4594 if (time > 0) {
4595 unpackTime(&absTime, isAbsolute, time);
4596 }
4597
4598
4599 // Enter safepoint region
4600 // Beware of deadlocks such as 6317397.
4601 // The per-thread Parker:: mutex is a classic leaf-lock.
4602 // In particular a thread must never block on the Threads_lock while
4603 // holding the Parker:: mutex. If safepoints are pending both the
4604 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4605 ThreadBlockInVM tbivm(jt);
4606
4607 // Don't wait if cannot get lock since interference arises from
4608 // unblocking. Also. check interrupt before trying wait
4609 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4610 return;
4611 }
4612
4613 int status ;
4614 if (_counter > 0) { // no wait needed
4615 _counter = 0;
4616 status = pthread_mutex_unlock(_mutex);
4617 assert (status == 0, "invariant") ;
4618 // Paranoia to ensure our locked and lock-free paths interact
4619 // correctly with each other and Java-level accesses.
4620 OrderAccess::fence();
4621 return;
4622 }
4623
4624 #ifdef ASSERT
4625 // Don't catch signals while blocked; let the running threads have the signals.
4626 // (This allows a debugger to break into the running thread.)
4627 sigset_t oldsigs;
4628 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4629 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4630 #endif
4631
4632 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4633 jt->set_suspend_equivalent();
4634 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4635
4636 if (time == 0) {
4637 status = pthread_cond_wait (_cond, _mutex) ;
4638 } else {
4639 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4640 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4641 pthread_cond_destroy (_cond) ;
4642 pthread_cond_init (_cond, NULL);
4643 }
4644 }
4645 assert_status(status == 0 || status == EINTR ||
4646 status == ETIMEDOUT,
4647 status, "cond_timedwait");
4648
4649 #ifdef ASSERT
4650 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4651 #endif
4652
4653 _counter = 0 ;
4654 status = pthread_mutex_unlock(_mutex) ;
4655 assert_status(status == 0, status, "invariant") ;
4656 // Paranoia to ensure our locked and lock-free paths interact
4657 // correctly with each other and Java-level accesses.
4658 OrderAccess::fence();
4659
4660 // If externally suspended while waiting, re-suspend
4661 if (jt->handle_special_suspend_equivalent_condition()) {
4662 jt->java_suspend_self();
4663 }
4664 }
4665
4666 void Parker::unpark() {
4667 int s, status ;
4668 status = pthread_mutex_lock(_mutex);
4669 assert (status == 0, "invariant") ;
4670 s = _counter;
4671 _counter = 1;
4672 if (s < 1) {
4673 if (WorkAroundNPTLTimedWaitHang) {
4674 status = pthread_cond_signal (_cond) ;
4675 assert (status == 0, "invariant") ;
4676 status = pthread_mutex_unlock(_mutex);
4677 assert (status == 0, "invariant") ;
4678 } else {
4679 status = pthread_mutex_unlock(_mutex);
4680 assert (status == 0, "invariant") ;
4681 status = pthread_cond_signal (_cond) ;
4682 assert (status == 0, "invariant") ;
4683 }
4684 } else {
4685 pthread_mutex_unlock(_mutex);
4686 assert (status == 0, "invariant") ;
4687 }
4688 }
4689
4690
4691 /* Darwin has no "environ" in a dynamic library. */
4692 #ifdef __APPLE__
4693 #include <crt_externs.h>
4694 #define environ (*_NSGetEnviron())
4695 #else
4696 extern char** environ;
4697 #endif
4698
4699 // Run the specified command in a separate process. Return its exit value,
4700 // or -1 on failure (e.g. can't fork a new process).
4701 // Unlike system(), this function can be called from signal handler. It
4702 // doesn't block SIGINT et al.
4703 int os::fork_and_exec(char* cmd) {
4704 const char * argv[4] = {"sh", "-c", cmd, NULL};
4705
4706 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4707 // pthread_atfork handlers and reset pthread library. All we need is a
4708 // separate process to execve. Make a direct syscall to fork process.
4709 // On IA64 there's no fork syscall, we have to use fork() and hope for
4710 // the best...
4711 pid_t pid = fork();
4712
4713 if (pid < 0) {
4714 // fork failed
4715 return -1;
4716
4717 } else if (pid == 0) {
4718 // child process
4719
4720 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4721 // first to kill every thread on the thread list. Because this list is
4722 // not reset by fork() (see notes above), execve() will instead kill
4723 // every thread in the parent process. We know this is the only thread
4724 // in the new process, so make a system call directly.
4725 // IA64 should use normal execve() from glibc to match the glibc fork()
4726 // above.
4727 execve("/bin/sh", (char* const*)argv, environ);
4728
4729 // execve failed
4730 _exit(-1);
4731
4732 } else {
4733 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4734 // care about the actual exit code, for now.
4735
4736 int status;
4737
4738 // Wait for the child process to exit. This returns immediately if
4739 // the child has already exited. */
4740 while (waitpid(pid, &status, 0) < 0) {
4741 switch (errno) {
4742 case ECHILD: return 0;
4743 case EINTR: break;
4744 default: return -1;
4745 }
4746 }
4747
4748 if (WIFEXITED(status)) {
4749 // The child exited normally; get its exit code.
4750 return WEXITSTATUS(status);
4751 } else if (WIFSIGNALED(status)) {
4752 // The child exited because of a signal
4753 // The best value to return is 0x80 + signal number,
4754 // because that is what all Unix shells do, and because
4755 // it allows callers to distinguish between process exit and
4756 // process death by signal.
4757 return 0x80 + WTERMSIG(status);
4758 } else {
4759 // Unknown exit code; pass it through
4760 return status;
4761 }
4762 }
4763 }
4764
4765 // is_headless_jre()
4766 //
4767 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4768 // in order to report if we are running in a headless jre
4769 //
4770 // Since JDK8 xawt/libmawt.so was moved into the same directory
4771 // as libawt.so, and renamed libawt_xawt.so
4772 //
4773 bool os::is_headless_jre() {
4774 #ifdef __APPLE__
4775 // We no longer build headless-only on Mac OS X
4776 return false;
4777 #else
4778 struct stat statbuf;
4779 char buf[MAXPATHLEN];
4780 char libmawtpath[MAXPATHLEN];
4781 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4782 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4783 char *p;
4784
4785 // Get path to libjvm.so
4786 os::jvm_path(buf, sizeof(buf));
4787
4788 // Get rid of libjvm.so
4789 p = strrchr(buf, '/');
4790 if (p == NULL) return false;
4791 else *p = '\0';
4792
4793 // Get rid of client or server
4794 p = strrchr(buf, '/');
4795 if (p == NULL) return false;
4796 else *p = '\0';
4797
4798 // check xawt/libmawt.so
4799 strcpy(libmawtpath, buf);
4800 strcat(libmawtpath, xawtstr);
4801 if (::stat(libmawtpath, &statbuf) == 0) return false;
4802
4803 // check libawt_xawt.so
4804 strcpy(libmawtpath, buf);
4805 strcat(libmawtpath, new_xawtstr);
4806 if (::stat(libmawtpath, &statbuf) == 0) return false;
4807
4808 return true;
4809 #endif
4810 }
4811
4812 // Get the default path to the core file
4813 // Returns the length of the string
4814 int os::get_core_path(char* buffer, size_t bufferSize) {
4815 int n = jio_snprintf(buffer, bufferSize, "/cores");
4816
4817 // Truncate if theoretical string was longer than bufferSize
4818 n = MIN2(n, (int)bufferSize);
4819
4820 return n;
4821 }
4822
4823 #ifndef PRODUCT
4824 void TestReserveMemorySpecial_test() {
4825 // No tests available for this platform
4826 }
4827 #endif