1 /*
2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/orderAccess.inline.hpp"
52 #include "runtime/osThread.hpp"
53 #include "runtime/perfMemory.hpp"
54 #include "runtime/sharedRuntime.hpp"
55 #include "runtime/statSampler.hpp"
56 #include "runtime/stubRoutines.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "runtime/threadCritical.hpp"
59 #include "runtime/timer.hpp"
60 #include "services/attachListener.hpp"
61 #include "services/memTracker.hpp"
62 #include "services/runtimeService.hpp"
63 #include "utilities/decoder.hpp"
64 #include "utilities/defaultStream.hpp"
65 #include "utilities/events.hpp"
66 #include "utilities/growableArray.hpp"
67 #include "utilities/vmError.hpp"
68
69 // put OS-includes here
70 # include <sys/types.h>
71 # include <sys/mman.h>
72 # include <sys/stat.h>
73 # include <sys/select.h>
74 # include <pthread.h>
75 # include <signal.h>
76 # include <errno.h>
77 # include <dlfcn.h>
78 # include <stdio.h>
79 # include <unistd.h>
80 # include <sys/resource.h>
81 # include <pthread.h>
82 # include <sys/stat.h>
83 # include <sys/time.h>
84 # include <sys/times.h>
85 # include <sys/utsname.h>
86 # include <sys/socket.h>
87 # include <sys/wait.h>
88 # include <time.h>
89 # include <pwd.h>
90 # include <poll.h>
91 # include <semaphore.h>
92 # include <fcntl.h>
93 # include <string.h>
94 # include <sys/param.h>
95 # include <sys/sysctl.h>
96 # include <sys/ipc.h>
97 # include <sys/shm.h>
98 #ifndef __APPLE__
99 # include <link.h>
100 #endif
101 # include <stdint.h>
102 # include <inttypes.h>
103 # include <sys/ioctl.h>
104 # include <sys/syscall.h>
105
106 #if defined(__FreeBSD__) || defined(__NetBSD__)
107 # include <elf.h>
108 #endif
109
110 #ifdef __APPLE__
111 # include <mach/mach.h> // semaphore_* API
112 # include <mach-o/dyld.h>
113 # include <sys/proc_info.h>
114 # include <objc/objc-auto.h>
115 #endif
116
117 #ifndef MAP_ANONYMOUS
118 #define MAP_ANONYMOUS MAP_ANON
119 #endif
120
121 #define MAX_PATH (2 * K)
122
123 // for timer info max values which include all bits
124 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
125
126 #define LARGEPAGES_BIT (1 << 6)
127
128 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
129
130 ////////////////////////////////////////////////////////////////////////////////
131 // global variables
132 julong os::Bsd::_physical_memory = 0;
133
134 #ifdef __APPLE__
135 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
136 volatile uint64_t os::Bsd::_max_abstime = 0;
137 #else
138 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
139 #endif
140 pthread_t os::Bsd::_main_thread;
141 int os::Bsd::_page_size = -1;
142
143 static jlong initial_time_count=0;
144
145 static int clock_tics_per_sec = 100;
146
147 // For diagnostics to print a message once. see run_periodic_checks
148 static sigset_t check_signal_done;
149 static bool check_signals = true;
150
151 static pid_t _initial_pid = 0;
152
153 /* Signal number used to suspend/resume a thread */
154
155 /* do not use any signal number less than SIGSEGV, see 4355769 */
156 static int SR_signum = SIGUSR2;
157 sigset_t SR_sigset;
158
159
160 ////////////////////////////////////////////////////////////////////////////////
161 // utility functions
162
163 static int SR_initialize();
164 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
165
166 julong os::available_memory() {
167 return Bsd::available_memory();
168 }
169
170 // available here means free
171 julong os::Bsd::available_memory() {
172 uint64_t available = physical_memory() >> 2;
173 #ifdef __APPLE__
174 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
175 vm_statistics64_data_t vmstat;
176 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
177 (host_info64_t)&vmstat, &count);
178 assert(kerr == KERN_SUCCESS,
179 "host_statistics64 failed - check mach_host_self() and count");
180 if (kerr == KERN_SUCCESS) {
181 available = vmstat.free_count * os::vm_page_size();
182 }
183 #endif
184 return available;
185 }
186
187 julong os::physical_memory() {
188 return Bsd::physical_memory();
189 }
190
191 ////////////////////////////////////////////////////////////////////////////////
192 // environment support
193
194 bool os::getenv(const char* name, char* buf, int len) {
195 const char* val = ::getenv(name);
196 if (val != NULL && strlen(val) < (size_t)len) {
197 strcpy(buf, val);
198 return true;
199 }
200 if (len > 0) buf[0] = 0; // return a null string
201 return false;
202 }
203
204
205 // Return true if user is running as root.
206
207 bool os::have_special_privileges() {
208 static bool init = false;
209 static bool privileges = false;
210 if (!init) {
211 privileges = (getuid() != geteuid()) || (getgid() != getegid());
212 init = true;
213 }
214 return privileges;
215 }
216
217
218
219 // Cpu architecture string
220 #if defined(ZERO)
221 static char cpu_arch[] = ZERO_LIBARCH;
222 #elif defined(IA64)
223 static char cpu_arch[] = "ia64";
224 #elif defined(IA32)
225 static char cpu_arch[] = "i386";
226 #elif defined(AMD64)
227 static char cpu_arch[] = "amd64";
228 #elif defined(ARM)
229 static char cpu_arch[] = "arm";
230 #elif defined(PPC32)
231 static char cpu_arch[] = "ppc";
232 #elif defined(SPARC)
233 # ifdef _LP64
234 static char cpu_arch[] = "sparcv9";
235 # else
236 static char cpu_arch[] = "sparc";
237 # endif
238 #else
239 #error Add appropriate cpu_arch setting
240 #endif
241
242 // Compiler variant
243 #ifdef COMPILER2
244 #define COMPILER_VARIANT "server"
245 #else
246 #define COMPILER_VARIANT "client"
247 #endif
248
249
250 void os::Bsd::initialize_system_info() {
251 int mib[2];
252 size_t len;
253 int cpu_val;
254 julong mem_val;
255
256 /* get processors count via hw.ncpus sysctl */
257 mib[0] = CTL_HW;
258 mib[1] = HW_NCPU;
259 len = sizeof(cpu_val);
260 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
261 assert(len == sizeof(cpu_val), "unexpected data size");
262 set_processor_count(cpu_val);
263 }
264 else {
265 set_processor_count(1); // fallback
266 }
267
268 /* get physical memory via hw.memsize sysctl (hw.memsize is used
269 * since it returns a 64 bit value)
270 */
271 mib[0] = CTL_HW;
272
273 #if defined (HW_MEMSIZE) // Apple
274 mib[1] = HW_MEMSIZE;
275 #elif defined(HW_PHYSMEM) // Most of BSD
276 mib[1] = HW_PHYSMEM;
277 #elif defined(HW_REALMEM) // Old FreeBSD
278 mib[1] = HW_REALMEM;
279 #else
280 #error No ways to get physmem
281 #endif
282
283 len = sizeof(mem_val);
284 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
285 assert(len == sizeof(mem_val), "unexpected data size");
286 _physical_memory = mem_val;
287 } else {
288 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
289 }
290
291 #ifdef __OpenBSD__
292 {
293 // limit _physical_memory memory view on OpenBSD since
294 // datasize rlimit restricts us anyway.
295 struct rlimit limits;
296 getrlimit(RLIMIT_DATA, &limits);
297 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
298 }
299 #endif
300 }
301
302 #ifdef __APPLE__
303 static const char *get_home() {
304 const char *home_dir = ::getenv("HOME");
305 if ((home_dir == NULL) || (*home_dir == '\0')) {
306 struct passwd *passwd_info = getpwuid(geteuid());
307 if (passwd_info != NULL) {
308 home_dir = passwd_info->pw_dir;
309 }
310 }
311
312 return home_dir;
313 }
314 #endif
315
316 void os::init_system_properties_values() {
317 // The next steps are taken in the product version:
318 //
319 // Obtain the JAVA_HOME value from the location of libjvm.so.
320 // This library should be located at:
321 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
322 //
323 // If "/jre/lib/" appears at the right place in the path, then we
324 // assume libjvm.so is installed in a JDK and we use this path.
325 //
326 // Otherwise exit with message: "Could not create the Java virtual machine."
327 //
328 // The following extra steps are taken in the debugging version:
329 //
330 // If "/jre/lib/" does NOT appear at the right place in the path
331 // instead of exit check for $JAVA_HOME environment variable.
332 //
333 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
334 // then we append a fake suffix "hotspot/libjvm.so" to this path so
335 // it looks like libjvm.so is installed there
336 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
337 //
338 // Otherwise exit.
339 //
340 // Important note: if the location of libjvm.so changes this
341 // code needs to be changed accordingly.
342
343 // See ld(1):
344 // The linker uses the following search paths to locate required
345 // shared libraries:
346 // 1: ...
347 // ...
348 // 7: The default directories, normally /lib and /usr/lib.
349 #ifndef DEFAULT_LIBPATH
350 #define DEFAULT_LIBPATH "/lib:/usr/lib"
351 #endif
352
353 // Base path of extensions installed on the system.
354 #define SYS_EXT_DIR "/usr/java/packages"
355 #define EXTENSIONS_DIR "/lib/ext"
356 #define ENDORSED_DIR "/lib/endorsed"
357
358 #ifndef __APPLE__
359
360 // Buffer that fits several sprintfs.
361 // Note that the space for the colon and the trailing null are provided
362 // by the nulls included by the sizeof operator.
363 const size_t bufsize =
364 MAX3((size_t)MAXPATHLEN, // For dll_dir & friends.
365 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir
366 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
367 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
368
369 // sysclasspath, java_home, dll_dir
370 {
371 char *pslash;
372 os::jvm_path(buf, bufsize);
373
374 // Found the full path to libjvm.so.
375 // Now cut the path to <java_home>/jre if we can.
376 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
377 pslash = strrchr(buf, '/');
378 if (pslash != NULL) {
379 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
380 }
381 Arguments::set_dll_dir(buf);
382
383 if (pslash != NULL) {
384 pslash = strrchr(buf, '/');
385 if (pslash != NULL) {
386 *pslash = '\0'; // Get rid of /<arch>.
387 pslash = strrchr(buf, '/');
388 if (pslash != NULL) {
389 *pslash = '\0'; // Get rid of /lib.
390 }
391 }
392 }
393 Arguments::set_java_home(buf);
394 set_boot_path('/', ':');
395 }
396
397 // Where to look for native libraries.
398 //
399 // Note: Due to a legacy implementation, most of the library path
400 // is set in the launcher. This was to accomodate linking restrictions
401 // on legacy Bsd implementations (which are no longer supported).
402 // Eventually, all the library path setting will be done here.
403 //
404 // However, to prevent the proliferation of improperly built native
405 // libraries, the new path component /usr/java/packages is added here.
406 // Eventually, all the library path setting will be done here.
407 {
408 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
409 // should always exist (until the legacy problem cited above is
410 // addressed).
411 const char *v = ::getenv("LD_LIBRARY_PATH");
412 const char *v_colon = ":";
413 if (v == NULL) { v = ""; v_colon = ""; }
414 // That's +1 for the colon and +1 for the trailing '\0'.
415 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
416 strlen(v) + 1 +
417 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
418 mtInternal);
419 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
420 Arguments::set_library_path(ld_library_path);
421 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
422 }
423
424 // Extensions directories.
425 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
426 Arguments::set_ext_dirs(buf);
427
428 // Endorsed standards default directory.
429 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
430 Arguments::set_endorsed_dirs(buf);
431
432 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
433
434 #else // __APPLE__
435
436 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
437 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
438
439 const char *user_home_dir = get_home();
440 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
441 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
442 sizeof(SYS_EXTENSIONS_DIRS);
443
444 // Buffer that fits several sprintfs.
445 // Note that the space for the colon and the trailing null are provided
446 // by the nulls included by the sizeof operator.
447 const size_t bufsize =
448 MAX3((size_t)MAXPATHLEN, // for dll_dir & friends.
449 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir
450 (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir
451 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
452
453 // sysclasspath, java_home, dll_dir
454 {
455 char *pslash;
456 os::jvm_path(buf, bufsize);
457
458 // Found the full path to libjvm.so.
459 // Now cut the path to <java_home>/jre if we can.
460 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
461 pslash = strrchr(buf, '/');
462 if (pslash != NULL) {
463 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
464 }
465 Arguments::set_dll_dir(buf);
466
467 if (pslash != NULL) {
468 pslash = strrchr(buf, '/');
469 if (pslash != NULL) {
470 *pslash = '\0'; // Get rid of /lib.
471 }
472 }
473 Arguments::set_java_home(buf);
474 set_boot_path('/', ':');
475 }
476
477 // Where to look for native libraries.
478 //
479 // Note: Due to a legacy implementation, most of the library path
480 // is set in the launcher. This was to accomodate linking restrictions
481 // on legacy Bsd implementations (which are no longer supported).
482 // Eventually, all the library path setting will be done here.
483 //
484 // However, to prevent the proliferation of improperly built native
485 // libraries, the new path component /usr/java/packages is added here.
486 // Eventually, all the library path setting will be done here.
487 {
488 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
489 // should always exist (until the legacy problem cited above is
490 // addressed).
491 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
492 // can specify a directory inside an app wrapper
493 const char *l = ::getenv("JAVA_LIBRARY_PATH");
494 const char *l_colon = ":";
495 if (l == NULL) { l = ""; l_colon = ""; }
496
497 const char *v = ::getenv("DYLD_LIBRARY_PATH");
498 const char *v_colon = ":";
499 if (v == NULL) { v = ""; v_colon = ""; }
500
501 // Apple's Java6 has "." at the beginning of java.library.path.
502 // OpenJDK on Windows has "." at the end of java.library.path.
503 // OpenJDK on Linux and Solaris don't have "." in java.library.path
504 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
505 // "." is appended to the end of java.library.path. Yes, this
506 // could cause a change in behavior, but Apple's Java6 behavior
507 // can be achieved by putting "." at the beginning of the
508 // JAVA_LIBRARY_PATH environment variable.
509 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
510 strlen(v) + 1 + strlen(l) + 1 +
511 system_ext_size + 3,
512 mtInternal);
513 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
514 v, v_colon, l, l_colon, user_home_dir);
515 Arguments::set_library_path(ld_library_path);
516 FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal);
517 }
518
519 // Extensions directories.
520 //
521 // Note that the space for the colon and the trailing null are provided
522 // by the nulls included by the sizeof operator (so actually one byte more
523 // than necessary is allocated).
524 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
525 user_home_dir, Arguments::get_java_home());
526 Arguments::set_ext_dirs(buf);
527
528 // Endorsed standards default directory.
529 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
530 Arguments::set_endorsed_dirs(buf);
531
532 FREE_C_HEAP_ARRAY(char, buf, mtInternal);
533
534 #undef SYS_EXTENSIONS_DIR
535 #undef SYS_EXTENSIONS_DIRS
536
537 #endif // __APPLE__
538
539 #undef SYS_EXT_DIR
540 #undef EXTENSIONS_DIR
541 #undef ENDORSED_DIR
542 }
543
544 ////////////////////////////////////////////////////////////////////////////////
545 // breakpoint support
546
547 void os::breakpoint() {
548 BREAKPOINT;
549 }
550
551 extern "C" void breakpoint() {
552 // use debugger to set breakpoint here
553 }
554
555 ////////////////////////////////////////////////////////////////////////////////
556 // signal support
557
558 debug_only(static bool signal_sets_initialized = false);
559 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
560
561 bool os::Bsd::is_sig_ignored(int sig) {
562 struct sigaction oact;
563 sigaction(sig, (struct sigaction*)NULL, &oact);
564 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
565 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
566 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
567 return true;
568 else
569 return false;
570 }
571
572 void os::Bsd::signal_sets_init() {
573 // Should also have an assertion stating we are still single-threaded.
574 assert(!signal_sets_initialized, "Already initialized");
575 // Fill in signals that are necessarily unblocked for all threads in
576 // the VM. Currently, we unblock the following signals:
577 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
578 // by -Xrs (=ReduceSignalUsage));
579 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
580 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
581 // the dispositions or masks wrt these signals.
582 // Programs embedding the VM that want to use the above signals for their
583 // own purposes must, at this time, use the "-Xrs" option to prevent
584 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
585 // (See bug 4345157, and other related bugs).
586 // In reality, though, unblocking these signals is really a nop, since
587 // these signals are not blocked by default.
588 sigemptyset(&unblocked_sigs);
589 sigemptyset(&allowdebug_blocked_sigs);
590 sigaddset(&unblocked_sigs, SIGILL);
591 sigaddset(&unblocked_sigs, SIGSEGV);
592 sigaddset(&unblocked_sigs, SIGBUS);
593 sigaddset(&unblocked_sigs, SIGFPE);
594 sigaddset(&unblocked_sigs, SR_signum);
595
596 if (!ReduceSignalUsage) {
597 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
598 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
599 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
600 }
601 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
602 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
603 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
604 }
605 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
606 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
607 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
608 }
609 }
610 // Fill in signals that are blocked by all but the VM thread.
611 sigemptyset(&vm_sigs);
612 if (!ReduceSignalUsage)
613 sigaddset(&vm_sigs, BREAK_SIGNAL);
614 debug_only(signal_sets_initialized = true);
615
616 }
617
618 // These are signals that are unblocked while a thread is running Java.
619 // (For some reason, they get blocked by default.)
620 sigset_t* os::Bsd::unblocked_signals() {
621 assert(signal_sets_initialized, "Not initialized");
622 return &unblocked_sigs;
623 }
624
625 // These are the signals that are blocked while a (non-VM) thread is
626 // running Java. Only the VM thread handles these signals.
627 sigset_t* os::Bsd::vm_signals() {
628 assert(signal_sets_initialized, "Not initialized");
629 return &vm_sigs;
630 }
631
632 // These are signals that are blocked during cond_wait to allow debugger in
633 sigset_t* os::Bsd::allowdebug_blocked_signals() {
634 assert(signal_sets_initialized, "Not initialized");
635 return &allowdebug_blocked_sigs;
636 }
637
638 void os::Bsd::hotspot_sigmask(Thread* thread) {
639
640 //Save caller's signal mask before setting VM signal mask
641 sigset_t caller_sigmask;
642 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
643
644 OSThread* osthread = thread->osthread();
645 osthread->set_caller_sigmask(caller_sigmask);
646
647 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
648
649 if (!ReduceSignalUsage) {
650 if (thread->is_VM_thread()) {
651 // Only the VM thread handles BREAK_SIGNAL ...
652 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
653 } else {
654 // ... all other threads block BREAK_SIGNAL
655 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
656 }
657 }
658 }
659
660
661 //////////////////////////////////////////////////////////////////////////////
662 // create new thread
663
664 // check if it's safe to start a new thread
665 static bool _thread_safety_check(Thread* thread) {
666 return true;
667 }
668
669 #ifdef __APPLE__
670 // library handle for calling objc_registerThreadWithCollector()
671 // without static linking to the libobjc library
672 #define OBJC_LIB "/usr/lib/libobjc.dylib"
673 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
674 typedef void (*objc_registerThreadWithCollector_t)();
675 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
676 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
677 #endif
678
679 #ifdef __APPLE__
680 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
681 // Additional thread_id used to correlate threads in SA
682 thread_identifier_info_data_t m_ident_info;
683 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
684
685 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
686 (thread_info_t) &m_ident_info, &count);
687
688 return m_ident_info.thread_id;
689 }
690 #endif
691
692 // Thread start routine for all newly created threads
693 static void *java_start(Thread *thread) {
694 // Try to randomize the cache line index of hot stack frames.
695 // This helps when threads of the same stack traces evict each other's
696 // cache lines. The threads can be either from the same JVM instance, or
697 // from different JVM instances. The benefit is especially true for
698 // processors with hyperthreading technology.
699 static int counter = 0;
700 int pid = os::current_process_id();
701 alloca(((pid ^ counter++) & 7) * 128);
702
703 ThreadLocalStorage::set_thread(thread);
704
705 OSThread* osthread = thread->osthread();
706 Monitor* sync = osthread->startThread_lock();
707
708 // non floating stack BsdThreads needs extra check, see above
709 if (!_thread_safety_check(thread)) {
710 // notify parent thread
711 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
712 osthread->set_state(ZOMBIE);
713 sync->notify_all();
714 return NULL;
715 }
716
717 osthread->set_thread_id(os::Bsd::gettid());
718
719 #ifdef __APPLE__
720 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
721 guarantee(unique_thread_id != 0, "unique thread id was not found");
722 osthread->set_unique_thread_id(unique_thread_id);
723 #endif
724 // initialize signal mask for this thread
725 os::Bsd::hotspot_sigmask(thread);
726
727 // initialize floating point control register
728 os::Bsd::init_thread_fpu_state();
729
730 #ifdef __APPLE__
731 // register thread with objc gc
732 if (objc_registerThreadWithCollectorFunction != NULL) {
733 objc_registerThreadWithCollectorFunction();
734 }
735 #endif
736
737 // handshaking with parent thread
738 {
739 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
740
741 // notify parent thread
742 osthread->set_state(INITIALIZED);
743 sync->notify_all();
744
745 // wait until os::start_thread()
746 while (osthread->get_state() == INITIALIZED) {
747 sync->wait(Mutex::_no_safepoint_check_flag);
748 }
749 }
750
751 // call one more level start routine
752 thread->run();
753
754 return 0;
755 }
756
757 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
758 assert(thread->osthread() == NULL, "caller responsible");
759
760 // Allocate the OSThread object
761 OSThread* osthread = new OSThread(NULL, NULL);
762 if (osthread == NULL) {
763 return false;
764 }
765
766 // set the correct thread state
767 osthread->set_thread_type(thr_type);
768
769 // Initial state is ALLOCATED but not INITIALIZED
770 osthread->set_state(ALLOCATED);
771
772 thread->set_osthread(osthread);
773
774 // init thread attributes
775 pthread_attr_t attr;
776 pthread_attr_init(&attr);
777 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
778
779 // stack size
780 if (os::Bsd::supports_variable_stack_size()) {
781 // calculate stack size if it's not specified by caller
782 if (stack_size == 0) {
783 stack_size = os::Bsd::default_stack_size(thr_type);
784
785 switch (thr_type) {
786 case os::java_thread:
787 // Java threads use ThreadStackSize which default value can be
788 // changed with the flag -Xss
789 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
790 stack_size = JavaThread::stack_size_at_create();
791 break;
792 case os::compiler_thread:
793 if (CompilerThreadStackSize > 0) {
794 stack_size = (size_t)(CompilerThreadStackSize * K);
795 break;
796 } // else fall through:
797 // use VMThreadStackSize if CompilerThreadStackSize is not defined
798 case os::vm_thread:
799 case os::pgc_thread:
800 case os::cgc_thread:
801 case os::watcher_thread:
802 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
803 break;
804 }
805 }
806
807 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
808 pthread_attr_setstacksize(&attr, stack_size);
809 } else {
810 // let pthread_create() pick the default value.
811 }
812
813 ThreadState state;
814
815 {
816 pthread_t tid;
817 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
818
819 pthread_attr_destroy(&attr);
820
821 if (ret != 0) {
822 if (PrintMiscellaneous && (Verbose || WizardMode)) {
823 perror("pthread_create()");
824 }
825 // Need to clean up stuff we've allocated so far
826 thread->set_osthread(NULL);
827 delete osthread;
828 return false;
829 }
830
831 // Store pthread info into the OSThread
832 osthread->set_pthread_id(tid);
833
834 // Wait until child thread is either initialized or aborted
835 {
836 Monitor* sync_with_child = osthread->startThread_lock();
837 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
838 while ((state = osthread->get_state()) == ALLOCATED) {
839 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
840 }
841 }
842
843 }
844
845 // Aborted due to thread limit being reached
846 if (state == ZOMBIE) {
847 thread->set_osthread(NULL);
848 delete osthread;
849 return false;
850 }
851
852 // The thread is returned suspended (in state INITIALIZED),
853 // and is started higher up in the call chain
854 assert(state == INITIALIZED, "race condition");
855 return true;
856 }
857
858 /////////////////////////////////////////////////////////////////////////////
859 // attach existing thread
860
861 // bootstrap the main thread
862 bool os::create_main_thread(JavaThread* thread) {
863 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
864 return create_attached_thread(thread);
865 }
866
867 bool os::create_attached_thread(JavaThread* thread) {
868 #ifdef ASSERT
869 thread->verify_not_published();
870 #endif
871
872 // Allocate the OSThread object
873 OSThread* osthread = new OSThread(NULL, NULL);
874
875 if (osthread == NULL) {
876 return false;
877 }
878
879 osthread->set_thread_id(os::Bsd::gettid());
880
881 // Store pthread info into the OSThread
882 #ifdef __APPLE__
883 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
884 guarantee(unique_thread_id != 0, "just checking");
885 osthread->set_unique_thread_id(unique_thread_id);
886 #endif
887 osthread->set_pthread_id(::pthread_self());
888
889 // initialize floating point control register
890 os::Bsd::init_thread_fpu_state();
891
892 // Initial thread state is RUNNABLE
893 osthread->set_state(RUNNABLE);
894
895 thread->set_osthread(osthread);
896
897 // initialize signal mask for this thread
898 // and save the caller's signal mask
899 os::Bsd::hotspot_sigmask(thread);
900
901 return true;
902 }
903
904 void os::pd_start_thread(Thread* thread) {
905 OSThread * osthread = thread->osthread();
906 assert(osthread->get_state() != INITIALIZED, "just checking");
907 Monitor* sync_with_child = osthread->startThread_lock();
908 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
909 sync_with_child->notify();
910 }
911
912 // Free Bsd resources related to the OSThread
913 void os::free_thread(OSThread* osthread) {
914 assert(osthread != NULL, "osthread not set");
915
916 if (Thread::current()->osthread() == osthread) {
917 // Restore caller's signal mask
918 sigset_t sigmask = osthread->caller_sigmask();
919 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
920 }
921
922 delete osthread;
923 }
924
925 //////////////////////////////////////////////////////////////////////////////
926 // thread local storage
927
928 // Restore the thread pointer if the destructor is called. This is in case
929 // someone from JNI code sets up a destructor with pthread_key_create to run
930 // detachCurrentThread on thread death. Unless we restore the thread pointer we
931 // will hang or crash. When detachCurrentThread is called the key will be set
932 // to null and we will not be called again. If detachCurrentThread is never
933 // called we could loop forever depending on the pthread implementation.
934 static void restore_thread_pointer(void* p) {
935 Thread* thread = (Thread*) p;
936 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
937 }
938
939 int os::allocate_thread_local_storage() {
940 pthread_key_t key;
941 int rslt = pthread_key_create(&key, restore_thread_pointer);
942 assert(rslt == 0, "cannot allocate thread local storage");
943 return (int)key;
944 }
945
946 // Note: This is currently not used by VM, as we don't destroy TLS key
947 // on VM exit.
948 void os::free_thread_local_storage(int index) {
949 int rslt = pthread_key_delete((pthread_key_t)index);
950 assert(rslt == 0, "invalid index");
951 }
952
953 void os::thread_local_storage_at_put(int index, void* value) {
954 int rslt = pthread_setspecific((pthread_key_t)index, value);
955 assert(rslt == 0, "pthread_setspecific failed");
956 }
957
958 extern "C" Thread* get_thread() {
959 return ThreadLocalStorage::thread();
960 }
961
962
963 ////////////////////////////////////////////////////////////////////////////////
964 // time support
965
966 // Time since start-up in seconds to a fine granularity.
967 // Used by VMSelfDestructTimer and the MemProfiler.
968 double os::elapsedTime() {
969
970 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
971 }
972
973 jlong os::elapsed_counter() {
974 return javaTimeNanos() - initial_time_count;
975 }
976
977 jlong os::elapsed_frequency() {
978 return NANOSECS_PER_SEC; // nanosecond resolution
979 }
980
981 bool os::supports_vtime() { return true; }
982 bool os::enable_vtime() { return false; }
983 bool os::vtime_enabled() { return false; }
984
985 double os::elapsedVTime() {
986 // better than nothing, but not much
987 return elapsedTime();
988 }
989
990 jlong os::javaTimeMillis() {
991 timeval time;
992 int status = gettimeofday(&time, NULL);
993 assert(status != -1, "bsd error");
994 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
995 }
996
997 #ifndef __APPLE__
998 #ifndef CLOCK_MONOTONIC
999 #define CLOCK_MONOTONIC (1)
1000 #endif
1001 #endif
1002
1003 #ifdef __APPLE__
1004 void os::Bsd::clock_init() {
1005 mach_timebase_info(&_timebase_info);
1006 }
1007 #else
1008 void os::Bsd::clock_init() {
1009 struct timespec res;
1010 struct timespec tp;
1011 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
1012 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
1013 // yes, monotonic clock is supported
1014 _clock_gettime = ::clock_gettime;
1015 }
1016 }
1017 #endif
1018
1019
1020 #ifdef __APPLE__
1021
1022 jlong os::javaTimeNanos() {
1023 const uint64_t tm = mach_absolute_time();
1024 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
1025 const uint64_t prev = Bsd::_max_abstime;
1026 if (now <= prev) {
1027 return prev; // same or retrograde time;
1028 }
1029 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
1030 assert(obsv >= prev, "invariant"); // Monotonicity
1031 // If the CAS succeeded then we're done and return "now".
1032 // If the CAS failed and the observed value "obsv" is >= now then
1033 // we should return "obsv". If the CAS failed and now > obsv > prv then
1034 // some other thread raced this thread and installed a new value, in which case
1035 // we could either (a) retry the entire operation, (b) retry trying to install now
1036 // or (c) just return obsv. We use (c). No loop is required although in some cases
1037 // we might discard a higher "now" value in deference to a slightly lower but freshly
1038 // installed obsv value. That's entirely benign -- it admits no new orderings compared
1039 // to (a) or (b) -- and greatly reduces coherence traffic.
1040 // We might also condition (c) on the magnitude of the delta between obsv and now.
1041 // Avoiding excessive CAS operations to hot RW locations is critical.
1042 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1043 return (prev == obsv) ? now : obsv;
1044 }
1045
1046 #else // __APPLE__
1047
1048 jlong os::javaTimeNanos() {
1049 if (Bsd::supports_monotonic_clock()) {
1050 struct timespec tp;
1051 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1052 assert(status == 0, "gettime error");
1053 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1054 return result;
1055 } else {
1056 timeval time;
1057 int status = gettimeofday(&time, NULL);
1058 assert(status != -1, "bsd error");
1059 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1060 return 1000 * usecs;
1061 }
1062 }
1063
1064 #endif // __APPLE__
1065
1066 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1067 if (Bsd::supports_monotonic_clock()) {
1068 info_ptr->max_value = ALL_64_BITS;
1069
1070 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1071 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1072 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1073 } else {
1074 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1075 info_ptr->max_value = ALL_64_BITS;
1076
1077 // gettimeofday is a real time clock so it skips
1078 info_ptr->may_skip_backward = true;
1079 info_ptr->may_skip_forward = true;
1080 }
1081
1082 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1083 }
1084
1085 // Return the real, user, and system times in seconds from an
1086 // arbitrary fixed point in the past.
1087 bool os::getTimesSecs(double* process_real_time,
1088 double* process_user_time,
1089 double* process_system_time) {
1090 struct tms ticks;
1091 clock_t real_ticks = times(&ticks);
1092
1093 if (real_ticks == (clock_t) (-1)) {
1094 return false;
1095 } else {
1096 double ticks_per_second = (double) clock_tics_per_sec;
1097 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1098 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1099 *process_real_time = ((double) real_ticks) / ticks_per_second;
1100
1101 return true;
1102 }
1103 }
1104
1105
1106 char * os::local_time_string(char *buf, size_t buflen) {
1107 struct tm t;
1108 time_t long_time;
1109 time(&long_time);
1110 localtime_r(&long_time, &t);
1111 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1112 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1113 t.tm_hour, t.tm_min, t.tm_sec);
1114 return buf;
1115 }
1116
1117 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1118 return localtime_r(clock, res);
1119 }
1120
1121 ////////////////////////////////////////////////////////////////////////////////
1122 // runtime exit support
1123
1124 // Note: os::shutdown() might be called very early during initialization, or
1125 // called from signal handler. Before adding something to os::shutdown(), make
1126 // sure it is async-safe and can handle partially initialized VM.
1127 void os::shutdown() {
1128
1129 // allow PerfMemory to attempt cleanup of any persistent resources
1130 perfMemory_exit();
1131
1132 // needs to remove object in file system
1133 AttachListener::abort();
1134
1135 // flush buffered output, finish log files
1136 ostream_abort();
1137
1138 // Check for abort hook
1139 abort_hook_t abort_hook = Arguments::abort_hook();
1140 if (abort_hook != NULL) {
1141 abort_hook();
1142 }
1143
1144 }
1145
1146 // Note: os::abort() might be called very early during initialization, or
1147 // called from signal handler. Before adding something to os::abort(), make
1148 // sure it is async-safe and can handle partially initialized VM.
1149 void os::abort(bool dump_core) {
1150 os::shutdown();
1151 if (dump_core) {
1152 #ifndef PRODUCT
1153 fdStream out(defaultStream::output_fd());
1154 out.print_raw("Current thread is ");
1155 char buf[16];
1156 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1157 out.print_raw_cr(buf);
1158 out.print_raw_cr("Dumping core ...");
1159 #endif
1160 ::abort(); // dump core
1161 }
1162
1163 ::exit(1);
1164 }
1165
1166 // Die immediately, no exit hook, no abort hook, no cleanup.
1167 void os::die() {
1168 // _exit() on BsdThreads only kills current thread
1169 ::abort();
1170 }
1171
1172 // This method is a copy of JDK's sysGetLastErrorString
1173 // from src/solaris/hpi/src/system_md.c
1174
1175 size_t os::lasterror(char *buf, size_t len) {
1176
1177 if (errno == 0) return 0;
1178
1179 const char *s = ::strerror(errno);
1180 size_t n = ::strlen(s);
1181 if (n >= len) {
1182 n = len - 1;
1183 }
1184 ::strncpy(buf, s, n);
1185 buf[n] = '\0';
1186 return n;
1187 }
1188
1189 // Information of current thread in variety of formats
1190 pid_t os::Bsd::gettid() {
1191 int retval = -1;
1192
1193 #ifdef __APPLE__ //XNU kernel
1194 // despite the fact mach port is actually not a thread id use it
1195 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1196 retval = ::pthread_mach_thread_np(::pthread_self());
1197 guarantee(retval != 0, "just checking");
1198 return retval;
1199
1200 #else
1201 #ifdef __FreeBSD__
1202 retval = syscall(SYS_thr_self);
1203 #else
1204 #ifdef __OpenBSD__
1205 retval = syscall(SYS_getthrid);
1206 #else
1207 #ifdef __NetBSD__
1208 retval = (pid_t) syscall(SYS__lwp_self);
1209 #endif
1210 #endif
1211 #endif
1212 #endif
1213
1214 if (retval == -1) {
1215 return getpid();
1216 }
1217 }
1218
1219 intx os::current_thread_id() {
1220 #ifdef __APPLE__
1221 return (intx)::pthread_mach_thread_np(::pthread_self());
1222 #else
1223 return (intx)::pthread_self();
1224 #endif
1225 }
1226
1227 int os::current_process_id() {
1228
1229 // Under the old bsd thread library, bsd gives each thread
1230 // its own process id. Because of this each thread will return
1231 // a different pid if this method were to return the result
1232 // of getpid(2). Bsd provides no api that returns the pid
1233 // of the launcher thread for the vm. This implementation
1234 // returns a unique pid, the pid of the launcher thread
1235 // that starts the vm 'process'.
1236
1237 // Under the NPTL, getpid() returns the same pid as the
1238 // launcher thread rather than a unique pid per thread.
1239 // Use gettid() if you want the old pre NPTL behaviour.
1240
1241 // if you are looking for the result of a call to getpid() that
1242 // returns a unique pid for the calling thread, then look at the
1243 // OSThread::thread_id() method in osThread_bsd.hpp file
1244
1245 return (int)(_initial_pid ? _initial_pid : getpid());
1246 }
1247
1248 // DLL functions
1249
1250 #define JNI_LIB_PREFIX "lib"
1251 #ifdef __APPLE__
1252 #define JNI_LIB_SUFFIX ".dylib"
1253 #else
1254 #define JNI_LIB_SUFFIX ".so"
1255 #endif
1256
1257 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1258
1259 // This must be hard coded because it's the system's temporary
1260 // directory not the java application's temp directory, ala java.io.tmpdir.
1261 #ifdef __APPLE__
1262 // macosx has a secure per-user temporary directory
1263 char temp_path_storage[PATH_MAX];
1264 const char* os::get_temp_directory() {
1265 static char *temp_path = NULL;
1266 if (temp_path == NULL) {
1267 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1268 if (pathSize == 0 || pathSize > PATH_MAX) {
1269 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1270 }
1271 temp_path = temp_path_storage;
1272 }
1273 return temp_path;
1274 }
1275 #else /* __APPLE__ */
1276 const char* os::get_temp_directory() { return "/tmp"; }
1277 #endif /* __APPLE__ */
1278
1279 static bool file_exists(const char* filename) {
1280 struct stat statbuf;
1281 if (filename == NULL || strlen(filename) == 0) {
1282 return false;
1283 }
1284 return os::stat(filename, &statbuf) == 0;
1285 }
1286
1287 bool os::dll_build_name(char* buffer, size_t buflen,
1288 const char* pname, const char* fname) {
1289 bool retval = false;
1290 // Copied from libhpi
1291 const size_t pnamelen = pname ? strlen(pname) : 0;
1292
1293 // Return error on buffer overflow.
1294 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1295 return retval;
1296 }
1297
1298 if (pnamelen == 0) {
1299 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1300 retval = true;
1301 } else if (strchr(pname, *os::path_separator()) != NULL) {
1302 int n;
1303 char** pelements = split_path(pname, &n);
1304 if (pelements == NULL) {
1305 return false;
1306 }
1307 for (int i = 0 ; i < n ; i++) {
1308 // Really shouldn't be NULL, but check can't hurt
1309 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1310 continue; // skip the empty path values
1311 }
1312 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1313 pelements[i], fname);
1314 if (file_exists(buffer)) {
1315 retval = true;
1316 break;
1317 }
1318 }
1319 // release the storage
1320 for (int i = 0 ; i < n ; i++) {
1321 if (pelements[i] != NULL) {
1322 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1323 }
1324 }
1325 if (pelements != NULL) {
1326 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1327 }
1328 } else {
1329 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1330 retval = true;
1331 }
1332 return retval;
1333 }
1334
1335 // check if addr is inside libjvm.so
1336 bool os::address_is_in_vm(address addr) {
1337 static address libjvm_base_addr;
1338 Dl_info dlinfo;
1339
1340 if (libjvm_base_addr == NULL) {
1341 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1342 libjvm_base_addr = (address)dlinfo.dli_fbase;
1343 }
1344 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1345 }
1346
1347 if (dladdr((void *)addr, &dlinfo) != 0) {
1348 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1349 }
1350
1351 return false;
1352 }
1353
1354
1355 #define MACH_MAXSYMLEN 256
1356
1357 bool os::dll_address_to_function_name(address addr, char *buf,
1358 int buflen, int *offset) {
1359 // buf is not optional, but offset is optional
1360 assert(buf != NULL, "sanity check");
1361
1362 Dl_info dlinfo;
1363 char localbuf[MACH_MAXSYMLEN];
1364
1365 if (dladdr((void*)addr, &dlinfo) != 0) {
1366 // see if we have a matching symbol
1367 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1368 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1369 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1370 }
1371 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1372 return true;
1373 }
1374 // no matching symbol so try for just file info
1375 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1376 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1377 buf, buflen, offset, dlinfo.dli_fname)) {
1378 return true;
1379 }
1380 }
1381
1382 // Handle non-dynamic manually:
1383 if (dlinfo.dli_fbase != NULL &&
1384 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1385 dlinfo.dli_fbase)) {
1386 if (!Decoder::demangle(localbuf, buf, buflen)) {
1387 jio_snprintf(buf, buflen, "%s", localbuf);
1388 }
1389 return true;
1390 }
1391 }
1392 buf[0] = '\0';
1393 if (offset != NULL) *offset = -1;
1394 return false;
1395 }
1396
1397 // ported from solaris version
1398 bool os::dll_address_to_library_name(address addr, char* buf,
1399 int buflen, int* offset) {
1400 // buf is not optional, but offset is optional
1401 assert(buf != NULL, "sanity check");
1402
1403 Dl_info dlinfo;
1404
1405 if (dladdr((void*)addr, &dlinfo) != 0) {
1406 if (dlinfo.dli_fname != NULL) {
1407 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1408 }
1409 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1410 *offset = addr - (address)dlinfo.dli_fbase;
1411 }
1412 return true;
1413 }
1414
1415 buf[0] = '\0';
1416 if (offset) *offset = -1;
1417 return false;
1418 }
1419
1420 // Loads .dll/.so and
1421 // in case of error it checks if .dll/.so was built for the
1422 // same architecture as Hotspot is running on
1423
1424 #ifdef __APPLE__
1425 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1426 void * result= ::dlopen(filename, RTLD_LAZY);
1427 if (result != NULL) {
1428 // Successful loading
1429 return result;
1430 }
1431
1432 // Read system error message into ebuf
1433 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1434 ebuf[ebuflen-1]='\0';
1435
1436 return NULL;
1437 }
1438 #else
1439 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1440 {
1441 void * result= ::dlopen(filename, RTLD_LAZY);
1442 if (result != NULL) {
1443 // Successful loading
1444 return result;
1445 }
1446
1447 Elf32_Ehdr elf_head;
1448
1449 // Read system error message into ebuf
1450 // It may or may not be overwritten below
1451 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1452 ebuf[ebuflen-1]='\0';
1453 int diag_msg_max_length=ebuflen-strlen(ebuf);
1454 char* diag_msg_buf=ebuf+strlen(ebuf);
1455
1456 if (diag_msg_max_length==0) {
1457 // No more space in ebuf for additional diagnostics message
1458 return NULL;
1459 }
1460
1461
1462 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1463
1464 if (file_descriptor < 0) {
1465 // Can't open library, report dlerror() message
1466 return NULL;
1467 }
1468
1469 bool failed_to_read_elf_head=
1470 (sizeof(elf_head)!=
1471 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1472
1473 ::close(file_descriptor);
1474 if (failed_to_read_elf_head) {
1475 // file i/o error - report dlerror() msg
1476 return NULL;
1477 }
1478
1479 typedef struct {
1480 Elf32_Half code; // Actual value as defined in elf.h
1481 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1482 char elf_class; // 32 or 64 bit
1483 char endianess; // MSB or LSB
1484 char* name; // String representation
1485 } arch_t;
1486
1487 #ifndef EM_486
1488 #define EM_486 6 /* Intel 80486 */
1489 #endif
1490
1491 #ifndef EM_MIPS_RS3_LE
1492 #define EM_MIPS_RS3_LE 10 /* MIPS */
1493 #endif
1494
1495 #ifndef EM_PPC64
1496 #define EM_PPC64 21 /* PowerPC64 */
1497 #endif
1498
1499 #ifndef EM_S390
1500 #define EM_S390 22 /* IBM System/390 */
1501 #endif
1502
1503 #ifndef EM_IA_64
1504 #define EM_IA_64 50 /* HP/Intel IA-64 */
1505 #endif
1506
1507 #ifndef EM_X86_64
1508 #define EM_X86_64 62 /* AMD x86-64 */
1509 #endif
1510
1511 static const arch_t arch_array[]={
1512 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1513 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1514 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1515 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1516 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1517 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1518 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1519 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1520 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1521 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1522 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1523 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1524 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1525 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1526 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1527 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1528 };
1529
1530 #if (defined IA32)
1531 static Elf32_Half running_arch_code=EM_386;
1532 #elif (defined AMD64)
1533 static Elf32_Half running_arch_code=EM_X86_64;
1534 #elif (defined IA64)
1535 static Elf32_Half running_arch_code=EM_IA_64;
1536 #elif (defined __sparc) && (defined _LP64)
1537 static Elf32_Half running_arch_code=EM_SPARCV9;
1538 #elif (defined __sparc) && (!defined _LP64)
1539 static Elf32_Half running_arch_code=EM_SPARC;
1540 #elif (defined __powerpc64__)
1541 static Elf32_Half running_arch_code=EM_PPC64;
1542 #elif (defined __powerpc__)
1543 static Elf32_Half running_arch_code=EM_PPC;
1544 #elif (defined ARM)
1545 static Elf32_Half running_arch_code=EM_ARM;
1546 #elif (defined S390)
1547 static Elf32_Half running_arch_code=EM_S390;
1548 #elif (defined ALPHA)
1549 static Elf32_Half running_arch_code=EM_ALPHA;
1550 #elif (defined MIPSEL)
1551 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1552 #elif (defined PARISC)
1553 static Elf32_Half running_arch_code=EM_PARISC;
1554 #elif (defined MIPS)
1555 static Elf32_Half running_arch_code=EM_MIPS;
1556 #elif (defined M68K)
1557 static Elf32_Half running_arch_code=EM_68K;
1558 #else
1559 #error Method os::dll_load requires that one of following is defined:\
1560 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1561 #endif
1562
1563 // Identify compatability class for VM's architecture and library's architecture
1564 // Obtain string descriptions for architectures
1565
1566 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1567 int running_arch_index=-1;
1568
1569 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1570 if (running_arch_code == arch_array[i].code) {
1571 running_arch_index = i;
1572 }
1573 if (lib_arch.code == arch_array[i].code) {
1574 lib_arch.compat_class = arch_array[i].compat_class;
1575 lib_arch.name = arch_array[i].name;
1576 }
1577 }
1578
1579 assert(running_arch_index != -1,
1580 "Didn't find running architecture code (running_arch_code) in arch_array");
1581 if (running_arch_index == -1) {
1582 // Even though running architecture detection failed
1583 // we may still continue with reporting dlerror() message
1584 return NULL;
1585 }
1586
1587 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1588 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1589 return NULL;
1590 }
1591
1592 #ifndef S390
1593 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1594 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1595 return NULL;
1596 }
1597 #endif // !S390
1598
1599 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1600 if ( lib_arch.name!=NULL ) {
1601 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1602 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1603 lib_arch.name, arch_array[running_arch_index].name);
1604 } else {
1605 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1606 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1607 lib_arch.code,
1608 arch_array[running_arch_index].name);
1609 }
1610 }
1611
1612 return NULL;
1613 }
1614 #endif /* !__APPLE__ */
1615
1616 void* os::get_default_process_handle() {
1617 #ifdef __APPLE__
1618 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1619 // to avoid finding unexpected symbols on second (or later)
1620 // loads of a library.
1621 return (void*)::dlopen(NULL, RTLD_FIRST);
1622 #else
1623 return (void*)::dlopen(NULL, RTLD_LAZY);
1624 #endif
1625 }
1626
1627 // XXX: Do we need a lock around this as per Linux?
1628 void* os::dll_lookup(void* handle, const char* name) {
1629 return dlsym(handle, name);
1630 }
1631
1632
1633 static bool _print_ascii_file(const char* filename, outputStream* st) {
1634 int fd = ::open(filename, O_RDONLY);
1635 if (fd == -1) {
1636 return false;
1637 }
1638
1639 char buf[32];
1640 int bytes;
1641 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1642 st->print_raw(buf, bytes);
1643 }
1644
1645 ::close(fd);
1646
1647 return true;
1648 }
1649
1650 void os::print_dll_info(outputStream *st) {
1651 st->print_cr("Dynamic libraries:");
1652 #ifdef RTLD_DI_LINKMAP
1653 Dl_info dli;
1654 void *handle;
1655 Link_map *map;
1656 Link_map *p;
1657
1658 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1659 dli.dli_fname == NULL) {
1660 st->print_cr("Error: Cannot print dynamic libraries.");
1661 return;
1662 }
1663 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1664 if (handle == NULL) {
1665 st->print_cr("Error: Cannot print dynamic libraries.");
1666 return;
1667 }
1668 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1669 if (map == NULL) {
1670 st->print_cr("Error: Cannot print dynamic libraries.");
1671 return;
1672 }
1673
1674 while (map->l_prev != NULL)
1675 map = map->l_prev;
1676
1677 while (map != NULL) {
1678 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1679 map = map->l_next;
1680 }
1681
1682 dlclose(handle);
1683 #elif defined(__APPLE__)
1684 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1685 st->print_cr(PTR_FORMAT " \t%s", _dyld_get_image_header(i),
1686 _dyld_get_image_name(i));
1687 }
1688 #else
1689 st->print_cr("Error: Cannot print dynamic libraries.");
1690 #endif
1691 }
1692
1693 void os::print_os_info_brief(outputStream* st) {
1694 st->print("Bsd");
1695
1696 os::Posix::print_uname_info(st);
1697 }
1698
1699 void os::print_os_info(outputStream* st) {
1700 st->print("OS:");
1701 st->print("Bsd");
1702
1703 os::Posix::print_uname_info(st);
1704
1705 os::Posix::print_rlimit_info(st);
1706
1707 os::Posix::print_load_average(st);
1708 }
1709
1710 void os::pd_print_cpu_info(outputStream* st) {
1711 // Nothing to do for now.
1712 }
1713
1714 void os::print_memory_info(outputStream* st) {
1715
1716 st->print("Memory:");
1717 st->print(" %dk page", os::vm_page_size()>>10);
1718
1719 st->print(", physical " UINT64_FORMAT "k",
1720 os::physical_memory() >> 10);
1721 st->print("(" UINT64_FORMAT "k free)",
1722 os::available_memory() >> 10);
1723 st->cr();
1724
1725 // meminfo
1726 st->print("\n/proc/meminfo:\n");
1727 _print_ascii_file("/proc/meminfo", st);
1728 st->cr();
1729 }
1730
1731 void os::print_siginfo(outputStream* st, void* siginfo) {
1732 const siginfo_t* si = (const siginfo_t*)siginfo;
1733
1734 os::Posix::print_siginfo_brief(st, si);
1735
1736 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1737 UseSharedSpaces) {
1738 FileMapInfo* mapinfo = FileMapInfo::current_info();
1739 if (mapinfo->is_in_shared_space(si->si_addr)) {
1740 st->print("\n\nError accessing class data sharing archive." \
1741 " Mapped file inaccessible during execution, " \
1742 " possible disk/network problem.");
1743 }
1744 }
1745 st->cr();
1746 }
1747
1748
1749 static void print_signal_handler(outputStream* st, int sig,
1750 char* buf, size_t buflen);
1751
1752 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1753 st->print_cr("Signal Handlers:");
1754 print_signal_handler(st, SIGSEGV, buf, buflen);
1755 print_signal_handler(st, SIGBUS , buf, buflen);
1756 print_signal_handler(st, SIGFPE , buf, buflen);
1757 print_signal_handler(st, SIGPIPE, buf, buflen);
1758 print_signal_handler(st, SIGXFSZ, buf, buflen);
1759 print_signal_handler(st, SIGILL , buf, buflen);
1760 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1761 print_signal_handler(st, SR_signum, buf, buflen);
1762 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1763 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1764 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1765 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1766 }
1767
1768 static char saved_jvm_path[MAXPATHLEN] = {0};
1769
1770 // Find the full path to the current module, libjvm
1771 void os::jvm_path(char *buf, jint buflen) {
1772 // Error checking.
1773 if (buflen < MAXPATHLEN) {
1774 assert(false, "must use a large-enough buffer");
1775 buf[0] = '\0';
1776 return;
1777 }
1778 // Lazy resolve the path to current module.
1779 if (saved_jvm_path[0] != 0) {
1780 strcpy(buf, saved_jvm_path);
1781 return;
1782 }
1783
1784 char dli_fname[MAXPATHLEN];
1785 bool ret = dll_address_to_library_name(
1786 CAST_FROM_FN_PTR(address, os::jvm_path),
1787 dli_fname, sizeof(dli_fname), NULL);
1788 assert(ret, "cannot locate libjvm");
1789 char *rp = NULL;
1790 if (ret && dli_fname[0] != '\0') {
1791 rp = realpath(dli_fname, buf);
1792 }
1793 if (rp == NULL)
1794 return;
1795
1796 if (Arguments::created_by_gamma_launcher()) {
1797 // Support for the gamma launcher. Typical value for buf is
1798 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1799 // the right place in the string, then assume we are installed in a JDK and
1800 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1801 // construct a path to the JVM being overridden.
1802
1803 const char *p = buf + strlen(buf) - 1;
1804 for (int count = 0; p > buf && count < 5; ++count) {
1805 for (--p; p > buf && *p != '/'; --p)
1806 /* empty */ ;
1807 }
1808
1809 if (strncmp(p, "/jre/lib/", 9) != 0) {
1810 // Look for JAVA_HOME in the environment.
1811 char* java_home_var = ::getenv("JAVA_HOME");
1812 if (java_home_var != NULL && java_home_var[0] != 0) {
1813 char* jrelib_p;
1814 int len;
1815
1816 // Check the current module name "libjvm"
1817 p = strrchr(buf, '/');
1818 assert(strstr(p, "/libjvm") == p, "invalid library name");
1819
1820 rp = realpath(java_home_var, buf);
1821 if (rp == NULL)
1822 return;
1823
1824 // determine if this is a legacy image or modules image
1825 // modules image doesn't have "jre" subdirectory
1826 len = strlen(buf);
1827 assert(len < buflen, "Ran out of buffer space");
1828 jrelib_p = buf + len;
1829
1830 // Add the appropriate library subdir
1831 snprintf(jrelib_p, buflen-len, "/jre/lib");
1832 if (0 != access(buf, F_OK)) {
1833 snprintf(jrelib_p, buflen-len, "/lib");
1834 }
1835
1836 // Add the appropriate client or server subdir
1837 len = strlen(buf);
1838 jrelib_p = buf + len;
1839 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1840 if (0 != access(buf, F_OK)) {
1841 snprintf(jrelib_p, buflen-len, "");
1842 }
1843
1844 // If the path exists within JAVA_HOME, add the JVM library name
1845 // to complete the path to JVM being overridden. Otherwise fallback
1846 // to the path to the current library.
1847 if (0 == access(buf, F_OK)) {
1848 // Use current module name "libjvm"
1849 len = strlen(buf);
1850 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1851 } else {
1852 // Fall back to path of current library
1853 rp = realpath(dli_fname, buf);
1854 if (rp == NULL)
1855 return;
1856 }
1857 }
1858 }
1859 }
1860
1861 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1862 }
1863
1864 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1865 // no prefix required, not even "_"
1866 }
1867
1868 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1869 // no suffix required
1870 }
1871
1872 ////////////////////////////////////////////////////////////////////////////////
1873 // sun.misc.Signal support
1874
1875 static volatile jint sigint_count = 0;
1876
1877 static void
1878 UserHandler(int sig, void *siginfo, void *context) {
1879 // 4511530 - sem_post is serialized and handled by the manager thread. When
1880 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1881 // don't want to flood the manager thread with sem_post requests.
1882 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1883 return;
1884
1885 // Ctrl-C is pressed during error reporting, likely because the error
1886 // handler fails to abort. Let VM die immediately.
1887 if (sig == SIGINT && is_error_reported()) {
1888 os::die();
1889 }
1890
1891 os::signal_notify(sig);
1892 }
1893
1894 void* os::user_handler() {
1895 return CAST_FROM_FN_PTR(void*, UserHandler);
1896 }
1897
1898 extern "C" {
1899 typedef void (*sa_handler_t)(int);
1900 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1901 }
1902
1903 void* os::signal(int signal_number, void* handler) {
1904 struct sigaction sigAct, oldSigAct;
1905
1906 sigfillset(&(sigAct.sa_mask));
1907 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1908 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1909
1910 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1911 // -1 means registration failed
1912 return (void *)-1;
1913 }
1914
1915 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1916 }
1917
1918 void os::signal_raise(int signal_number) {
1919 ::raise(signal_number);
1920 }
1921
1922 /*
1923 * The following code is moved from os.cpp for making this
1924 * code platform specific, which it is by its very nature.
1925 */
1926
1927 // Will be modified when max signal is changed to be dynamic
1928 int os::sigexitnum_pd() {
1929 return NSIG;
1930 }
1931
1932 // a counter for each possible signal value
1933 static volatile jint pending_signals[NSIG+1] = { 0 };
1934
1935 // Bsd(POSIX) specific hand shaking semaphore.
1936 #ifdef __APPLE__
1937 typedef semaphore_t os_semaphore_t;
1938 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1939 #define SEM_WAIT(sem) semaphore_wait(sem)
1940 #define SEM_POST(sem) semaphore_signal(sem)
1941 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1942 #else
1943 typedef sem_t os_semaphore_t;
1944 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1945 #define SEM_WAIT(sem) sem_wait(&sem)
1946 #define SEM_POST(sem) sem_post(&sem)
1947 #define SEM_DESTROY(sem) sem_destroy(&sem)
1948 #endif
1949
1950 class Semaphore : public StackObj {
1951 public:
1952 Semaphore();
1953 ~Semaphore();
1954 void signal();
1955 void wait();
1956 bool trywait();
1957 bool timedwait(unsigned int sec, int nsec);
1958 private:
1959 jlong currenttime() const;
1960 os_semaphore_t _semaphore;
1961 };
1962
1963 Semaphore::Semaphore() : _semaphore(0) {
1964 SEM_INIT(_semaphore, 0);
1965 }
1966
1967 Semaphore::~Semaphore() {
1968 SEM_DESTROY(_semaphore);
1969 }
1970
1971 void Semaphore::signal() {
1972 SEM_POST(_semaphore);
1973 }
1974
1975 void Semaphore::wait() {
1976 SEM_WAIT(_semaphore);
1977 }
1978
1979 jlong Semaphore::currenttime() const {
1980 struct timeval tv;
1981 gettimeofday(&tv, NULL);
1982 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1983 }
1984
1985 #ifdef __APPLE__
1986 bool Semaphore::trywait() {
1987 return timedwait(0, 0);
1988 }
1989
1990 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1991 kern_return_t kr = KERN_ABORTED;
1992 mach_timespec_t waitspec;
1993 waitspec.tv_sec = sec;
1994 waitspec.tv_nsec = nsec;
1995
1996 jlong starttime = currenttime();
1997
1998 kr = semaphore_timedwait(_semaphore, waitspec);
1999 while (kr == KERN_ABORTED) {
2000 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
2001
2002 jlong current = currenttime();
2003 jlong passedtime = current - starttime;
2004
2005 if (passedtime >= totalwait) {
2006 waitspec.tv_sec = 0;
2007 waitspec.tv_nsec = 0;
2008 } else {
2009 jlong waittime = totalwait - (current - starttime);
2010 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2011 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2012 }
2013
2014 kr = semaphore_timedwait(_semaphore, waitspec);
2015 }
2016
2017 return kr == KERN_SUCCESS;
2018 }
2019
2020 #else
2021
2022 bool Semaphore::trywait() {
2023 return sem_trywait(&_semaphore) == 0;
2024 }
2025
2026 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2027 struct timespec ts;
2028 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2029
2030 while (1) {
2031 int result = sem_timedwait(&_semaphore, &ts);
2032 if (result == 0) {
2033 return true;
2034 } else if (errno == EINTR) {
2035 continue;
2036 } else if (errno == ETIMEDOUT) {
2037 return false;
2038 } else {
2039 return false;
2040 }
2041 }
2042 }
2043
2044 #endif // __APPLE__
2045
2046 static os_semaphore_t sig_sem;
2047 static Semaphore sr_semaphore;
2048
2049 void os::signal_init_pd() {
2050 // Initialize signal structures
2051 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2052
2053 // Initialize signal semaphore
2054 ::SEM_INIT(sig_sem, 0);
2055 }
2056
2057 void os::signal_notify(int sig) {
2058 Atomic::inc(&pending_signals[sig]);
2059 ::SEM_POST(sig_sem);
2060 }
2061
2062 static int check_pending_signals(bool wait) {
2063 Atomic::store(0, &sigint_count);
2064 for (;;) {
2065 for (int i = 0; i < NSIG + 1; i++) {
2066 jint n = pending_signals[i];
2067 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2068 return i;
2069 }
2070 }
2071 if (!wait) {
2072 return -1;
2073 }
2074 JavaThread *thread = JavaThread::current();
2075 ThreadBlockInVM tbivm(thread);
2076
2077 bool threadIsSuspended;
2078 do {
2079 thread->set_suspend_equivalent();
2080 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2081 ::SEM_WAIT(sig_sem);
2082
2083 // were we externally suspended while we were waiting?
2084 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2085 if (threadIsSuspended) {
2086 //
2087 // The semaphore has been incremented, but while we were waiting
2088 // another thread suspended us. We don't want to continue running
2089 // while suspended because that would surprise the thread that
2090 // suspended us.
2091 //
2092 ::SEM_POST(sig_sem);
2093
2094 thread->java_suspend_self();
2095 }
2096 } while (threadIsSuspended);
2097 }
2098 }
2099
2100 int os::signal_lookup() {
2101 return check_pending_signals(false);
2102 }
2103
2104 int os::signal_wait() {
2105 return check_pending_signals(true);
2106 }
2107
2108 ////////////////////////////////////////////////////////////////////////////////
2109 // Virtual Memory
2110
2111 int os::vm_page_size() {
2112 // Seems redundant as all get out
2113 assert(os::Bsd::page_size() != -1, "must call os::init");
2114 return os::Bsd::page_size();
2115 }
2116
2117 // Solaris allocates memory by pages.
2118 int os::vm_allocation_granularity() {
2119 assert(os::Bsd::page_size() != -1, "must call os::init");
2120 return os::Bsd::page_size();
2121 }
2122
2123 // Rationale behind this function:
2124 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2125 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2126 // samples for JITted code. Here we create private executable mapping over the code cache
2127 // and then we can use standard (well, almost, as mapping can change) way to provide
2128 // info for the reporting script by storing timestamp and location of symbol
2129 void bsd_wrap_code(char* base, size_t size) {
2130 static volatile jint cnt = 0;
2131
2132 if (!UseOprofile) {
2133 return;
2134 }
2135
2136 char buf[PATH_MAX + 1];
2137 int num = Atomic::add(1, &cnt);
2138
2139 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2140 os::get_temp_directory(), os::current_process_id(), num);
2141 unlink(buf);
2142
2143 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2144
2145 if (fd != -1) {
2146 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2147 if (rv != (off_t)-1) {
2148 if (::write(fd, "", 1) == 1) {
2149 mmap(base, size,
2150 PROT_READ|PROT_WRITE|PROT_EXEC,
2151 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2152 }
2153 }
2154 ::close(fd);
2155 unlink(buf);
2156 }
2157 }
2158
2159 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2160 int err) {
2161 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2162 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2163 strerror(err), err);
2164 }
2165
2166 // NOTE: Bsd kernel does not really reserve the pages for us.
2167 // All it does is to check if there are enough free pages
2168 // left at the time of mmap(). This could be a potential
2169 // problem.
2170 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2171 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2172 #ifdef __OpenBSD__
2173 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2174 if (::mprotect(addr, size, prot) == 0) {
2175 return true;
2176 }
2177 #else
2178 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2179 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2180 if (res != (uintptr_t) MAP_FAILED) {
2181 return true;
2182 }
2183 #endif
2184
2185 // Warn about any commit errors we see in non-product builds just
2186 // in case mmap() doesn't work as described on the man page.
2187 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2188
2189 return false;
2190 }
2191
2192 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2193 bool exec) {
2194 // alignment_hint is ignored on this OS
2195 return pd_commit_memory(addr, size, exec);
2196 }
2197
2198 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2199 const char* mesg) {
2200 assert(mesg != NULL, "mesg must be specified");
2201 if (!pd_commit_memory(addr, size, exec)) {
2202 // add extra info in product mode for vm_exit_out_of_memory():
2203 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2204 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2205 }
2206 }
2207
2208 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2209 size_t alignment_hint, bool exec,
2210 const char* mesg) {
2211 // alignment_hint is ignored on this OS
2212 pd_commit_memory_or_exit(addr, size, exec, mesg);
2213 }
2214
2215 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2216 }
2217
2218 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2219 ::madvise(addr, bytes, MADV_DONTNEED);
2220 }
2221
2222 void os::numa_make_global(char *addr, size_t bytes) {
2223 }
2224
2225 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2226 }
2227
2228 bool os::numa_topology_changed() { return false; }
2229
2230 size_t os::numa_get_groups_num() {
2231 return 1;
2232 }
2233
2234 int os::numa_get_group_id() {
2235 return 0;
2236 }
2237
2238 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2239 if (size > 0) {
2240 ids[0] = 0;
2241 return 1;
2242 }
2243 return 0;
2244 }
2245
2246 bool os::get_page_info(char *start, page_info* info) {
2247 return false;
2248 }
2249
2250 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2251 return end;
2252 }
2253
2254
2255 bool os::pd_uncommit_memory(char* addr, size_t size) {
2256 #ifdef __OpenBSD__
2257 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2258 return ::mprotect(addr, size, PROT_NONE) == 0;
2259 #else
2260 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2261 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2262 return res != (uintptr_t) MAP_FAILED;
2263 #endif
2264 }
2265
2266 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2267 return os::commit_memory(addr, size, !ExecMem);
2268 }
2269
2270 // If this is a growable mapping, remove the guard pages entirely by
2271 // munmap()ping them. If not, just call uncommit_memory().
2272 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2273 return os::uncommit_memory(addr, size);
2274 }
2275
2276 static address _highest_vm_reserved_address = NULL;
2277
2278 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2279 // at 'requested_addr'. If there are existing memory mappings at the same
2280 // location, however, they will be overwritten. If 'fixed' is false,
2281 // 'requested_addr' is only treated as a hint, the return value may or
2282 // may not start from the requested address. Unlike Bsd mmap(), this
2283 // function returns NULL to indicate failure.
2284 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2285 char * addr;
2286 int flags;
2287
2288 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2289 if (fixed) {
2290 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2291 flags |= MAP_FIXED;
2292 }
2293
2294 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2295 // touch an uncommitted page. Otherwise, the read/write might
2296 // succeed if we have enough swap space to back the physical page.
2297 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2298 flags, -1, 0);
2299
2300 if (addr != MAP_FAILED) {
2301 // anon_mmap() should only get called during VM initialization,
2302 // don't need lock (actually we can skip locking even it can be called
2303 // from multiple threads, because _highest_vm_reserved_address is just a
2304 // hint about the upper limit of non-stack memory regions.)
2305 if ((address)addr + bytes > _highest_vm_reserved_address) {
2306 _highest_vm_reserved_address = (address)addr + bytes;
2307 }
2308 }
2309
2310 return addr == MAP_FAILED ? NULL : addr;
2311 }
2312
2313 // Don't update _highest_vm_reserved_address, because there might be memory
2314 // regions above addr + size. If so, releasing a memory region only creates
2315 // a hole in the address space, it doesn't help prevent heap-stack collision.
2316 //
2317 static int anon_munmap(char * addr, size_t size) {
2318 return ::munmap(addr, size) == 0;
2319 }
2320
2321 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2322 size_t alignment_hint) {
2323 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2324 }
2325
2326 bool os::pd_release_memory(char* addr, size_t size) {
2327 return anon_munmap(addr, size);
2328 }
2329
2330 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2331 // Bsd wants the mprotect address argument to be page aligned.
2332 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2333
2334 // According to SUSv3, mprotect() should only be used with mappings
2335 // established by mmap(), and mmap() always maps whole pages. Unaligned
2336 // 'addr' likely indicates problem in the VM (e.g. trying to change
2337 // protection of malloc'ed or statically allocated memory). Check the
2338 // caller if you hit this assert.
2339 assert(addr == bottom, "sanity check");
2340
2341 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2342 return ::mprotect(bottom, size, prot) == 0;
2343 }
2344
2345 // Set protections specified
2346 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2347 bool is_committed) {
2348 unsigned int p = 0;
2349 switch (prot) {
2350 case MEM_PROT_NONE: p = PROT_NONE; break;
2351 case MEM_PROT_READ: p = PROT_READ; break;
2352 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2353 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2354 default:
2355 ShouldNotReachHere();
2356 }
2357 // is_committed is unused.
2358 return bsd_mprotect(addr, bytes, p);
2359 }
2360
2361 bool os::guard_memory(char* addr, size_t size) {
2362 return bsd_mprotect(addr, size, PROT_NONE);
2363 }
2364
2365 bool os::unguard_memory(char* addr, size_t size) {
2366 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2367 }
2368
2369 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2370 return false;
2371 }
2372
2373 // Large page support
2374
2375 static size_t _large_page_size = 0;
2376
2377 void os::large_page_init() {
2378 }
2379
2380
2381 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2382 fatal("This code is not used or maintained.");
2383
2384 // "exec" is passed in but not used. Creating the shared image for
2385 // the code cache doesn't have an SHM_X executable permission to check.
2386 assert(UseLargePages && UseSHM, "only for SHM large pages");
2387
2388 key_t key = IPC_PRIVATE;
2389 char *addr;
2390
2391 bool warn_on_failure = UseLargePages &&
2392 (!FLAG_IS_DEFAULT(UseLargePages) ||
2393 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2394 );
2395
2396 // Create a large shared memory region to attach to based on size.
2397 // Currently, size is the total size of the heap
2398 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2399 if (shmid == -1) {
2400 // Possible reasons for shmget failure:
2401 // 1. shmmax is too small for Java heap.
2402 // > check shmmax value: cat /proc/sys/kernel/shmmax
2403 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2404 // 2. not enough large page memory.
2405 // > check available large pages: cat /proc/meminfo
2406 // > increase amount of large pages:
2407 // echo new_value > /proc/sys/vm/nr_hugepages
2408 // Note 1: different Bsd may use different name for this property,
2409 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2410 // Note 2: it's possible there's enough physical memory available but
2411 // they are so fragmented after a long run that they can't
2412 // coalesce into large pages. Try to reserve large pages when
2413 // the system is still "fresh".
2414 if (warn_on_failure) {
2415 warning("Failed to reserve shared memory (errno = %d).", errno);
2416 }
2417 return NULL;
2418 }
2419
2420 // attach to the region
2421 addr = (char*)shmat(shmid, req_addr, 0);
2422 int err = errno;
2423
2424 // Remove shmid. If shmat() is successful, the actual shared memory segment
2425 // will be deleted when it's detached by shmdt() or when the process
2426 // terminates. If shmat() is not successful this will remove the shared
2427 // segment immediately.
2428 shmctl(shmid, IPC_RMID, NULL);
2429
2430 if ((intptr_t)addr == -1) {
2431 if (warn_on_failure) {
2432 warning("Failed to attach shared memory (errno = %d).", err);
2433 }
2434 return NULL;
2435 }
2436
2437 // The memory is committed
2438 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2439
2440 return addr;
2441 }
2442
2443 bool os::release_memory_special(char* base, size_t bytes) {
2444 if (MemTracker::tracking_level() > NMT_minimal) {
2445 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2446 // detaching the SHM segment will also delete it, see reserve_memory_special()
2447 int rslt = shmdt(base);
2448 if (rslt == 0) {
2449 tkr.record((address)base, bytes);
2450 return true;
2451 } else {
2452 return false;
2453 }
2454 } else {
2455 return shmdt(base) == 0;
2456 }
2457 }
2458
2459 size_t os::large_page_size() {
2460 return _large_page_size;
2461 }
2462
2463 // HugeTLBFS allows application to commit large page memory on demand;
2464 // with SysV SHM the entire memory region must be allocated as shared
2465 // memory.
2466 bool os::can_commit_large_page_memory() {
2467 return UseHugeTLBFS;
2468 }
2469
2470 bool os::can_execute_large_page_memory() {
2471 return UseHugeTLBFS;
2472 }
2473
2474 // Reserve memory at an arbitrary address, only if that area is
2475 // available (and not reserved for something else).
2476
2477 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2478 const int max_tries = 10;
2479 char* base[max_tries];
2480 size_t size[max_tries];
2481 const size_t gap = 0x000000;
2482
2483 // Assert only that the size is a multiple of the page size, since
2484 // that's all that mmap requires, and since that's all we really know
2485 // about at this low abstraction level. If we need higher alignment,
2486 // we can either pass an alignment to this method or verify alignment
2487 // in one of the methods further up the call chain. See bug 5044738.
2488 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2489
2490 // Repeatedly allocate blocks until the block is allocated at the
2491 // right spot. Give up after max_tries. Note that reserve_memory() will
2492 // automatically update _highest_vm_reserved_address if the call is
2493 // successful. The variable tracks the highest memory address every reserved
2494 // by JVM. It is used to detect heap-stack collision if running with
2495 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2496 // space than needed, it could confuse the collision detecting code. To
2497 // solve the problem, save current _highest_vm_reserved_address and
2498 // calculate the correct value before return.
2499 address old_highest = _highest_vm_reserved_address;
2500
2501 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2502 // if kernel honors the hint then we can return immediately.
2503 char * addr = anon_mmap(requested_addr, bytes, false);
2504 if (addr == requested_addr) {
2505 return requested_addr;
2506 }
2507
2508 if (addr != NULL) {
2509 // mmap() is successful but it fails to reserve at the requested address
2510 anon_munmap(addr, bytes);
2511 }
2512
2513 int i;
2514 for (i = 0; i < max_tries; ++i) {
2515 base[i] = reserve_memory(bytes);
2516
2517 if (base[i] != NULL) {
2518 // Is this the block we wanted?
2519 if (base[i] == requested_addr) {
2520 size[i] = bytes;
2521 break;
2522 }
2523
2524 // Does this overlap the block we wanted? Give back the overlapped
2525 // parts and try again.
2526
2527 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2528 if (top_overlap >= 0 && top_overlap < bytes) {
2529 unmap_memory(base[i], top_overlap);
2530 base[i] += top_overlap;
2531 size[i] = bytes - top_overlap;
2532 } else {
2533 size_t bottom_overlap = base[i] + bytes - requested_addr;
2534 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2535 unmap_memory(requested_addr, bottom_overlap);
2536 size[i] = bytes - bottom_overlap;
2537 } else {
2538 size[i] = bytes;
2539 }
2540 }
2541 }
2542 }
2543
2544 // Give back the unused reserved pieces.
2545
2546 for (int j = 0; j < i; ++j) {
2547 if (base[j] != NULL) {
2548 unmap_memory(base[j], size[j]);
2549 }
2550 }
2551
2552 if (i < max_tries) {
2553 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2554 return requested_addr;
2555 } else {
2556 _highest_vm_reserved_address = old_highest;
2557 return NULL;
2558 }
2559 }
2560
2561 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2562 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2563 }
2564
2565 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2566 // Solaris uses poll(), bsd uses park().
2567 // Poll() is likely a better choice, assuming that Thread.interrupt()
2568 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2569 // SIGSEGV, see 4355769.
2570
2571 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2572 assert(thread == Thread::current(), "thread consistency check");
2573
2574 ParkEvent * const slp = thread->_SleepEvent ;
2575 slp->reset() ;
2576 OrderAccess::fence() ;
2577
2578 if (interruptible) {
2579 jlong prevtime = javaTimeNanos();
2580
2581 for (;;) {
2582 if (os::is_interrupted(thread, true)) {
2583 return OS_INTRPT;
2584 }
2585
2586 jlong newtime = javaTimeNanos();
2587
2588 if (newtime - prevtime < 0) {
2589 // time moving backwards, should only happen if no monotonic clock
2590 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2591 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2592 } else {
2593 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2594 }
2595
2596 if(millis <= 0) {
2597 return OS_OK;
2598 }
2599
2600 prevtime = newtime;
2601
2602 {
2603 assert(thread->is_Java_thread(), "sanity check");
2604 JavaThread *jt = (JavaThread *) thread;
2605 ThreadBlockInVM tbivm(jt);
2606 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2607
2608 jt->set_suspend_equivalent();
2609 // cleared by handle_special_suspend_equivalent_condition() or
2610 // java_suspend_self() via check_and_wait_while_suspended()
2611
2612 slp->park(millis);
2613
2614 // were we externally suspended while we were waiting?
2615 jt->check_and_wait_while_suspended();
2616 }
2617 }
2618 } else {
2619 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2620 jlong prevtime = javaTimeNanos();
2621
2622 for (;;) {
2623 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2624 // the 1st iteration ...
2625 jlong newtime = javaTimeNanos();
2626
2627 if (newtime - prevtime < 0) {
2628 // time moving backwards, should only happen if no monotonic clock
2629 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2630 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2631 } else {
2632 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2633 }
2634
2635 if(millis <= 0) break ;
2636
2637 prevtime = newtime;
2638 slp->park(millis);
2639 }
2640 return OS_OK ;
2641 }
2642 }
2643
2644 void os::naked_short_sleep(jlong ms) {
2645 struct timespec req;
2646
2647 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2648 req.tv_sec = 0;
2649 if (ms > 0) {
2650 req.tv_nsec = (ms % 1000) * 1000000;
2651 }
2652 else {
2653 req.tv_nsec = 1;
2654 }
2655
2656 nanosleep(&req, NULL);
2657
2658 return;
2659 }
2660
2661 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2662 void os::infinite_sleep() {
2663 while (true) { // sleep forever ...
2664 ::sleep(100); // ... 100 seconds at a time
2665 }
2666 }
2667
2668 // Used to convert frequent JVM_Yield() to nops
2669 bool os::dont_yield() {
2670 return DontYieldALot;
2671 }
2672
2673 void os::yield() {
2674 sched_yield();
2675 }
2676
2677 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2678
2679 void os::yield_all(int attempts) {
2680 // Yields to all threads, including threads with lower priorities
2681 // Threads on Bsd are all with same priority. The Solaris style
2682 // os::yield_all() with nanosleep(1ms) is not necessary.
2683 sched_yield();
2684 }
2685
2686 // Called from the tight loops to possibly influence time-sharing heuristics
2687 void os::loop_breaker(int attempts) {
2688 os::yield_all(attempts);
2689 }
2690
2691 ////////////////////////////////////////////////////////////////////////////////
2692 // thread priority support
2693
2694 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2695 // only supports dynamic priority, static priority must be zero. For real-time
2696 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2697 // However, for large multi-threaded applications, SCHED_RR is not only slower
2698 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2699 // of 5 runs - Sep 2005).
2700 //
2701 // The following code actually changes the niceness of kernel-thread/LWP. It
2702 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2703 // not the entire user process, and user level threads are 1:1 mapped to kernel
2704 // threads. It has always been the case, but could change in the future. For
2705 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2706 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2707
2708 #if !defined(__APPLE__)
2709 int os::java_to_os_priority[CriticalPriority + 1] = {
2710 19, // 0 Entry should never be used
2711
2712 0, // 1 MinPriority
2713 3, // 2
2714 6, // 3
2715
2716 10, // 4
2717 15, // 5 NormPriority
2718 18, // 6
2719
2720 21, // 7
2721 25, // 8
2722 28, // 9 NearMaxPriority
2723
2724 31, // 10 MaxPriority
2725
2726 31 // 11 CriticalPriority
2727 };
2728 #else
2729 /* Using Mach high-level priority assignments */
2730 int os::java_to_os_priority[CriticalPriority + 1] = {
2731 0, // 0 Entry should never be used (MINPRI_USER)
2732
2733 27, // 1 MinPriority
2734 28, // 2
2735 29, // 3
2736
2737 30, // 4
2738 31, // 5 NormPriority (BASEPRI_DEFAULT)
2739 32, // 6
2740
2741 33, // 7
2742 34, // 8
2743 35, // 9 NearMaxPriority
2744
2745 36, // 10 MaxPriority
2746
2747 36 // 11 CriticalPriority
2748 };
2749 #endif
2750
2751 static int prio_init() {
2752 if (ThreadPriorityPolicy == 1) {
2753 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2754 // if effective uid is not root. Perhaps, a more elegant way of doing
2755 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2756 if (geteuid() != 0) {
2757 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2758 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2759 }
2760 ThreadPriorityPolicy = 0;
2761 }
2762 }
2763 if (UseCriticalJavaThreadPriority) {
2764 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2765 }
2766 return 0;
2767 }
2768
2769 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2770 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2771
2772 #ifdef __OpenBSD__
2773 // OpenBSD pthread_setprio starves low priority threads
2774 return OS_OK;
2775 #elif defined(__FreeBSD__)
2776 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2777 #elif defined(__APPLE__) || defined(__NetBSD__)
2778 struct sched_param sp;
2779 int policy;
2780 pthread_t self = pthread_self();
2781
2782 if (pthread_getschedparam(self, &policy, &sp) != 0)
2783 return OS_ERR;
2784
2785 sp.sched_priority = newpri;
2786 if (pthread_setschedparam(self, policy, &sp) != 0)
2787 return OS_ERR;
2788
2789 return OS_OK;
2790 #else
2791 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2792 return (ret == 0) ? OS_OK : OS_ERR;
2793 #endif
2794 }
2795
2796 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2797 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2798 *priority_ptr = java_to_os_priority[NormPriority];
2799 return OS_OK;
2800 }
2801
2802 errno = 0;
2803 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2804 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2805 #elif defined(__APPLE__) || defined(__NetBSD__)
2806 int policy;
2807 struct sched_param sp;
2808
2809 pthread_getschedparam(pthread_self(), &policy, &sp);
2810 *priority_ptr = sp.sched_priority;
2811 #else
2812 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2813 #endif
2814 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2815 }
2816
2817 // Hint to the underlying OS that a task switch would not be good.
2818 // Void return because it's a hint and can fail.
2819 void os::hint_no_preempt() {}
2820
2821 ////////////////////////////////////////////////////////////////////////////////
2822 // suspend/resume support
2823
2824 // the low-level signal-based suspend/resume support is a remnant from the
2825 // old VM-suspension that used to be for java-suspension, safepoints etc,
2826 // within hotspot. Now there is a single use-case for this:
2827 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2828 // that runs in the watcher thread.
2829 // The remaining code is greatly simplified from the more general suspension
2830 // code that used to be used.
2831 //
2832 // The protocol is quite simple:
2833 // - suspend:
2834 // - sends a signal to the target thread
2835 // - polls the suspend state of the osthread using a yield loop
2836 // - target thread signal handler (SR_handler) sets suspend state
2837 // and blocks in sigsuspend until continued
2838 // - resume:
2839 // - sets target osthread state to continue
2840 // - sends signal to end the sigsuspend loop in the SR_handler
2841 //
2842 // Note that the SR_lock plays no role in this suspend/resume protocol.
2843 //
2844
2845 static void resume_clear_context(OSThread *osthread) {
2846 osthread->set_ucontext(NULL);
2847 osthread->set_siginfo(NULL);
2848 }
2849
2850 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2851 osthread->set_ucontext(context);
2852 osthread->set_siginfo(siginfo);
2853 }
2854
2855 //
2856 // Handler function invoked when a thread's execution is suspended or
2857 // resumed. We have to be careful that only async-safe functions are
2858 // called here (Note: most pthread functions are not async safe and
2859 // should be avoided.)
2860 //
2861 // Note: sigwait() is a more natural fit than sigsuspend() from an
2862 // interface point of view, but sigwait() prevents the signal hander
2863 // from being run. libpthread would get very confused by not having
2864 // its signal handlers run and prevents sigwait()'s use with the
2865 // mutex granting granting signal.
2866 //
2867 // Currently only ever called on the VMThread or JavaThread
2868 //
2869 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2870 // Save and restore errno to avoid confusing native code with EINTR
2871 // after sigsuspend.
2872 int old_errno = errno;
2873
2874 Thread* thread = Thread::current();
2875 OSThread* osthread = thread->osthread();
2876 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2877
2878 os::SuspendResume::State current = osthread->sr.state();
2879 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2880 suspend_save_context(osthread, siginfo, context);
2881
2882 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2883 os::SuspendResume::State state = osthread->sr.suspended();
2884 if (state == os::SuspendResume::SR_SUSPENDED) {
2885 sigset_t suspend_set; // signals for sigsuspend()
2886
2887 // get current set of blocked signals and unblock resume signal
2888 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2889 sigdelset(&suspend_set, SR_signum);
2890
2891 sr_semaphore.signal();
2892 // wait here until we are resumed
2893 while (1) {
2894 sigsuspend(&suspend_set);
2895
2896 os::SuspendResume::State result = osthread->sr.running();
2897 if (result == os::SuspendResume::SR_RUNNING) {
2898 sr_semaphore.signal();
2899 break;
2900 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2901 ShouldNotReachHere();
2902 }
2903 }
2904
2905 } else if (state == os::SuspendResume::SR_RUNNING) {
2906 // request was cancelled, continue
2907 } else {
2908 ShouldNotReachHere();
2909 }
2910
2911 resume_clear_context(osthread);
2912 } else if (current == os::SuspendResume::SR_RUNNING) {
2913 // request was cancelled, continue
2914 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2915 // ignore
2916 } else {
2917 // ignore
2918 }
2919
2920 errno = old_errno;
2921 }
2922
2923
2924 static int SR_initialize() {
2925 struct sigaction act;
2926 char *s;
2927 /* Get signal number to use for suspend/resume */
2928 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2929 int sig = ::strtol(s, 0, 10);
2930 if (sig > 0 || sig < NSIG) {
2931 SR_signum = sig;
2932 }
2933 }
2934
2935 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2936 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2937
2938 sigemptyset(&SR_sigset);
2939 sigaddset(&SR_sigset, SR_signum);
2940
2941 /* Set up signal handler for suspend/resume */
2942 act.sa_flags = SA_RESTART|SA_SIGINFO;
2943 act.sa_handler = (void (*)(int)) SR_handler;
2944
2945 // SR_signum is blocked by default.
2946 // 4528190 - We also need to block pthread restart signal (32 on all
2947 // supported Bsd platforms). Note that BsdThreads need to block
2948 // this signal for all threads to work properly. So we don't have
2949 // to use hard-coded signal number when setting up the mask.
2950 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2951
2952 if (sigaction(SR_signum, &act, 0) == -1) {
2953 return -1;
2954 }
2955
2956 // Save signal flag
2957 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2958 return 0;
2959 }
2960
2961 static int sr_notify(OSThread* osthread) {
2962 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2963 assert_status(status == 0, status, "pthread_kill");
2964 return status;
2965 }
2966
2967 // "Randomly" selected value for how long we want to spin
2968 // before bailing out on suspending a thread, also how often
2969 // we send a signal to a thread we want to resume
2970 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2971 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2972
2973 // returns true on success and false on error - really an error is fatal
2974 // but this seems the normal response to library errors
2975 static bool do_suspend(OSThread* osthread) {
2976 assert(osthread->sr.is_running(), "thread should be running");
2977 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2978
2979 // mark as suspended and send signal
2980 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2981 // failed to switch, state wasn't running?
2982 ShouldNotReachHere();
2983 return false;
2984 }
2985
2986 if (sr_notify(osthread) != 0) {
2987 ShouldNotReachHere();
2988 }
2989
2990 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2991 while (true) {
2992 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2993 break;
2994 } else {
2995 // timeout
2996 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2997 if (cancelled == os::SuspendResume::SR_RUNNING) {
2998 return false;
2999 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
3000 // make sure that we consume the signal on the semaphore as well
3001 sr_semaphore.wait();
3002 break;
3003 } else {
3004 ShouldNotReachHere();
3005 return false;
3006 }
3007 }
3008 }
3009
3010 guarantee(osthread->sr.is_suspended(), "Must be suspended");
3011 return true;
3012 }
3013
3014 static void do_resume(OSThread* osthread) {
3015 assert(osthread->sr.is_suspended(), "thread should be suspended");
3016 assert(!sr_semaphore.trywait(), "invalid semaphore state");
3017
3018 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
3019 // failed to switch to WAKEUP_REQUEST
3020 ShouldNotReachHere();
3021 return;
3022 }
3023
3024 while (true) {
3025 if (sr_notify(osthread) == 0) {
3026 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
3027 if (osthread->sr.is_running()) {
3028 return;
3029 }
3030 }
3031 } else {
3032 ShouldNotReachHere();
3033 }
3034 }
3035
3036 guarantee(osthread->sr.is_running(), "Must be running!");
3037 }
3038
3039 ////////////////////////////////////////////////////////////////////////////////
3040 // interrupt support
3041
3042 void os::interrupt(Thread* thread) {
3043 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3044 "possibility of dangling Thread pointer");
3045
3046 OSThread* osthread = thread->osthread();
3047
3048 if (!osthread->interrupted()) {
3049 osthread->set_interrupted(true);
3050 // More than one thread can get here with the same value of osthread,
3051 // resulting in multiple notifications. We do, however, want the store
3052 // to interrupted() to be visible to other threads before we execute unpark().
3053 OrderAccess::fence();
3054 ParkEvent * const slp = thread->_SleepEvent ;
3055 if (slp != NULL) slp->unpark() ;
3056 }
3057
3058 // For JSR166. Unpark even if interrupt status already was set
3059 if (thread->is_Java_thread())
3060 ((JavaThread*)thread)->parker()->unpark();
3061
3062 ParkEvent * ev = thread->_ParkEvent ;
3063 if (ev != NULL) ev->unpark() ;
3064
3065 }
3066
3067 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3068 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3069 "possibility of dangling Thread pointer");
3070
3071 OSThread* osthread = thread->osthread();
3072
3073 bool interrupted = osthread->interrupted();
3074
3075 if (interrupted && clear_interrupted) {
3076 osthread->set_interrupted(false);
3077 // consider thread->_SleepEvent->reset() ... optional optimization
3078 }
3079
3080 return interrupted;
3081 }
3082
3083 ///////////////////////////////////////////////////////////////////////////////////
3084 // signal handling (except suspend/resume)
3085
3086 // This routine may be used by user applications as a "hook" to catch signals.
3087 // The user-defined signal handler must pass unrecognized signals to this
3088 // routine, and if it returns true (non-zero), then the signal handler must
3089 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3090 // routine will never retun false (zero), but instead will execute a VM panic
3091 // routine kill the process.
3092 //
3093 // If this routine returns false, it is OK to call it again. This allows
3094 // the user-defined signal handler to perform checks either before or after
3095 // the VM performs its own checks. Naturally, the user code would be making
3096 // a serious error if it tried to handle an exception (such as a null check
3097 // or breakpoint) that the VM was generating for its own correct operation.
3098 //
3099 // This routine may recognize any of the following kinds of signals:
3100 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3101 // It should be consulted by handlers for any of those signals.
3102 //
3103 // The caller of this routine must pass in the three arguments supplied
3104 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3105 // field of the structure passed to sigaction(). This routine assumes that
3106 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3107 //
3108 // Note that the VM will print warnings if it detects conflicting signal
3109 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3110 //
3111 extern "C" JNIEXPORT int
3112 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3113 void* ucontext, int abort_if_unrecognized);
3114
3115 void signalHandler(int sig, siginfo_t* info, void* uc) {
3116 assert(info != NULL && uc != NULL, "it must be old kernel");
3117 int orig_errno = errno; // Preserve errno value over signal handler.
3118 JVM_handle_bsd_signal(sig, info, uc, true);
3119 errno = orig_errno;
3120 }
3121
3122
3123 // This boolean allows users to forward their own non-matching signals
3124 // to JVM_handle_bsd_signal, harmlessly.
3125 bool os::Bsd::signal_handlers_are_installed = false;
3126
3127 // For signal-chaining
3128 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3129 unsigned int os::Bsd::sigs = 0;
3130 bool os::Bsd::libjsig_is_loaded = false;
3131 typedef struct sigaction *(*get_signal_t)(int);
3132 get_signal_t os::Bsd::get_signal_action = NULL;
3133
3134 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3135 struct sigaction *actp = NULL;
3136
3137 if (libjsig_is_loaded) {
3138 // Retrieve the old signal handler from libjsig
3139 actp = (*get_signal_action)(sig);
3140 }
3141 if (actp == NULL) {
3142 // Retrieve the preinstalled signal handler from jvm
3143 actp = get_preinstalled_handler(sig);
3144 }
3145
3146 return actp;
3147 }
3148
3149 static bool call_chained_handler(struct sigaction *actp, int sig,
3150 siginfo_t *siginfo, void *context) {
3151 // Call the old signal handler
3152 if (actp->sa_handler == SIG_DFL) {
3153 // It's more reasonable to let jvm treat it as an unexpected exception
3154 // instead of taking the default action.
3155 return false;
3156 } else if (actp->sa_handler != SIG_IGN) {
3157 if ((actp->sa_flags & SA_NODEFER) == 0) {
3158 // automaticlly block the signal
3159 sigaddset(&(actp->sa_mask), sig);
3160 }
3161
3162 sa_handler_t hand;
3163 sa_sigaction_t sa;
3164 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3165 // retrieve the chained handler
3166 if (siginfo_flag_set) {
3167 sa = actp->sa_sigaction;
3168 } else {
3169 hand = actp->sa_handler;
3170 }
3171
3172 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3173 actp->sa_handler = SIG_DFL;
3174 }
3175
3176 // try to honor the signal mask
3177 sigset_t oset;
3178 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3179
3180 // call into the chained handler
3181 if (siginfo_flag_set) {
3182 (*sa)(sig, siginfo, context);
3183 } else {
3184 (*hand)(sig);
3185 }
3186
3187 // restore the signal mask
3188 pthread_sigmask(SIG_SETMASK, &oset, 0);
3189 }
3190 // Tell jvm's signal handler the signal is taken care of.
3191 return true;
3192 }
3193
3194 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3195 bool chained = false;
3196 // signal-chaining
3197 if (UseSignalChaining) {
3198 struct sigaction *actp = get_chained_signal_action(sig);
3199 if (actp != NULL) {
3200 chained = call_chained_handler(actp, sig, siginfo, context);
3201 }
3202 }
3203 return chained;
3204 }
3205
3206 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3207 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3208 return &sigact[sig];
3209 }
3210 return NULL;
3211 }
3212
3213 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3214 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3215 sigact[sig] = oldAct;
3216 sigs |= (unsigned int)1 << sig;
3217 }
3218
3219 // for diagnostic
3220 int os::Bsd::sigflags[MAXSIGNUM];
3221
3222 int os::Bsd::get_our_sigflags(int sig) {
3223 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3224 return sigflags[sig];
3225 }
3226
3227 void os::Bsd::set_our_sigflags(int sig, int flags) {
3228 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3229 sigflags[sig] = flags;
3230 }
3231
3232 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3233 // Check for overwrite.
3234 struct sigaction oldAct;
3235 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3236
3237 void* oldhand = oldAct.sa_sigaction
3238 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3239 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3240 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3241 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3242 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3243 if (AllowUserSignalHandlers || !set_installed) {
3244 // Do not overwrite; user takes responsibility to forward to us.
3245 return;
3246 } else if (UseSignalChaining) {
3247 // save the old handler in jvm
3248 save_preinstalled_handler(sig, oldAct);
3249 // libjsig also interposes the sigaction() call below and saves the
3250 // old sigaction on it own.
3251 } else {
3252 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3253 "%#lx for signal %d.", (long)oldhand, sig));
3254 }
3255 }
3256
3257 struct sigaction sigAct;
3258 sigfillset(&(sigAct.sa_mask));
3259 sigAct.sa_handler = SIG_DFL;
3260 if (!set_installed) {
3261 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3262 } else {
3263 sigAct.sa_sigaction = signalHandler;
3264 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3265 }
3266 #ifdef __APPLE__
3267 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3268 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3269 // if the signal handler declares it will handle it on alternate stack.
3270 // Notice we only declare we will handle it on alt stack, but we are not
3271 // actually going to use real alt stack - this is just a workaround.
3272 // Please see ux_exception.c, method catch_mach_exception_raise for details
3273 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3274 if (sig == SIGSEGV) {
3275 sigAct.sa_flags |= SA_ONSTACK;
3276 }
3277 #endif
3278
3279 // Save flags, which are set by ours
3280 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3281 sigflags[sig] = sigAct.sa_flags;
3282
3283 int ret = sigaction(sig, &sigAct, &oldAct);
3284 assert(ret == 0, "check");
3285
3286 void* oldhand2 = oldAct.sa_sigaction
3287 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3288 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3289 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3290 }
3291
3292 // install signal handlers for signals that HotSpot needs to
3293 // handle in order to support Java-level exception handling.
3294
3295 void os::Bsd::install_signal_handlers() {
3296 if (!signal_handlers_are_installed) {
3297 signal_handlers_are_installed = true;
3298
3299 // signal-chaining
3300 typedef void (*signal_setting_t)();
3301 signal_setting_t begin_signal_setting = NULL;
3302 signal_setting_t end_signal_setting = NULL;
3303 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3304 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3305 if (begin_signal_setting != NULL) {
3306 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3307 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3308 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3309 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3310 libjsig_is_loaded = true;
3311 assert(UseSignalChaining, "should enable signal-chaining");
3312 }
3313 if (libjsig_is_loaded) {
3314 // Tell libjsig jvm is setting signal handlers
3315 (*begin_signal_setting)();
3316 }
3317
3318 set_signal_handler(SIGSEGV, true);
3319 set_signal_handler(SIGPIPE, true);
3320 set_signal_handler(SIGBUS, true);
3321 set_signal_handler(SIGILL, true);
3322 set_signal_handler(SIGFPE, true);
3323 set_signal_handler(SIGXFSZ, true);
3324
3325 #if defined(__APPLE__)
3326 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3327 // signals caught and handled by the JVM. To work around this, we reset the mach task
3328 // signal handler that's placed on our process by CrashReporter. This disables
3329 // CrashReporter-based reporting.
3330 //
3331 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3332 // on caught fatal signals.
3333 //
3334 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3335 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3336 // exception handling, while leaving the standard BSD signal handlers functional.
3337 kern_return_t kr;
3338 kr = task_set_exception_ports(mach_task_self(),
3339 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3340 MACH_PORT_NULL,
3341 EXCEPTION_STATE_IDENTITY,
3342 MACHINE_THREAD_STATE);
3343
3344 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3345 #endif
3346
3347 if (libjsig_is_loaded) {
3348 // Tell libjsig jvm finishes setting signal handlers
3349 (*end_signal_setting)();
3350 }
3351
3352 // We don't activate signal checker if libjsig is in place, we trust ourselves
3353 // and if UserSignalHandler is installed all bets are off
3354 if (CheckJNICalls) {
3355 if (libjsig_is_loaded) {
3356 if (PrintJNIResolving) {
3357 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3358 }
3359 check_signals = false;
3360 }
3361 if (AllowUserSignalHandlers) {
3362 if (PrintJNIResolving) {
3363 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3364 }
3365 check_signals = false;
3366 }
3367 }
3368 }
3369 }
3370
3371
3372 /////
3373 // glibc on Bsd platform uses non-documented flag
3374 // to indicate, that some special sort of signal
3375 // trampoline is used.
3376 // We will never set this flag, and we should
3377 // ignore this flag in our diagnostic
3378 #ifdef SIGNIFICANT_SIGNAL_MASK
3379 #undef SIGNIFICANT_SIGNAL_MASK
3380 #endif
3381 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3382
3383 static const char* get_signal_handler_name(address handler,
3384 char* buf, int buflen) {
3385 int offset;
3386 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3387 if (found) {
3388 // skip directory names
3389 const char *p1, *p2;
3390 p1 = buf;
3391 size_t len = strlen(os::file_separator());
3392 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3393 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3394 } else {
3395 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3396 }
3397 return buf;
3398 }
3399
3400 static void print_signal_handler(outputStream* st, int sig,
3401 char* buf, size_t buflen) {
3402 struct sigaction sa;
3403
3404 sigaction(sig, NULL, &sa);
3405
3406 // See comment for SIGNIFICANT_SIGNAL_MASK define
3407 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3408
3409 st->print("%s: ", os::exception_name(sig, buf, buflen));
3410
3411 address handler = (sa.sa_flags & SA_SIGINFO)
3412 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3413 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3414
3415 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3416 st->print("SIG_DFL");
3417 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3418 st->print("SIG_IGN");
3419 } else {
3420 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3421 }
3422
3423 st->print(", sa_mask[0]=");
3424 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3425
3426 address rh = VMError::get_resetted_sighandler(sig);
3427 // May be, handler was resetted by VMError?
3428 if(rh != NULL) {
3429 handler = rh;
3430 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3431 }
3432
3433 st->print(", sa_flags=");
3434 os::Posix::print_sa_flags(st, sa.sa_flags);
3435
3436 // Check: is it our handler?
3437 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3438 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3439 // It is our signal handler
3440 // check for flags, reset system-used one!
3441 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3442 st->print(
3443 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3444 os::Bsd::get_our_sigflags(sig));
3445 }
3446 }
3447 st->cr();
3448 }
3449
3450
3451 #define DO_SIGNAL_CHECK(sig) \
3452 if (!sigismember(&check_signal_done, sig)) \
3453 os::Bsd::check_signal_handler(sig)
3454
3455 // This method is a periodic task to check for misbehaving JNI applications
3456 // under CheckJNI, we can add any periodic checks here
3457
3458 void os::run_periodic_checks() {
3459
3460 if (check_signals == false) return;
3461
3462 // SEGV and BUS if overridden could potentially prevent
3463 // generation of hs*.log in the event of a crash, debugging
3464 // such a case can be very challenging, so we absolutely
3465 // check the following for a good measure:
3466 DO_SIGNAL_CHECK(SIGSEGV);
3467 DO_SIGNAL_CHECK(SIGILL);
3468 DO_SIGNAL_CHECK(SIGFPE);
3469 DO_SIGNAL_CHECK(SIGBUS);
3470 DO_SIGNAL_CHECK(SIGPIPE);
3471 DO_SIGNAL_CHECK(SIGXFSZ);
3472
3473
3474 // ReduceSignalUsage allows the user to override these handlers
3475 // see comments at the very top and jvm_solaris.h
3476 if (!ReduceSignalUsage) {
3477 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3478 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3479 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3480 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3481 }
3482
3483 DO_SIGNAL_CHECK(SR_signum);
3484 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3485 }
3486
3487 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3488
3489 static os_sigaction_t os_sigaction = NULL;
3490
3491 void os::Bsd::check_signal_handler(int sig) {
3492 char buf[O_BUFLEN];
3493 address jvmHandler = NULL;
3494
3495
3496 struct sigaction act;
3497 if (os_sigaction == NULL) {
3498 // only trust the default sigaction, in case it has been interposed
3499 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3500 if (os_sigaction == NULL) return;
3501 }
3502
3503 os_sigaction(sig, (struct sigaction*)NULL, &act);
3504
3505
3506 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3507
3508 address thisHandler = (act.sa_flags & SA_SIGINFO)
3509 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3510 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3511
3512
3513 switch(sig) {
3514 case SIGSEGV:
3515 case SIGBUS:
3516 case SIGFPE:
3517 case SIGPIPE:
3518 case SIGILL:
3519 case SIGXFSZ:
3520 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3521 break;
3522
3523 case SHUTDOWN1_SIGNAL:
3524 case SHUTDOWN2_SIGNAL:
3525 case SHUTDOWN3_SIGNAL:
3526 case BREAK_SIGNAL:
3527 jvmHandler = (address)user_handler();
3528 break;
3529
3530 case INTERRUPT_SIGNAL:
3531 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3532 break;
3533
3534 default:
3535 if (sig == SR_signum) {
3536 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3537 } else {
3538 return;
3539 }
3540 break;
3541 }
3542
3543 if (thisHandler != jvmHandler) {
3544 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3545 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3546 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3547 // No need to check this sig any longer
3548 sigaddset(&check_signal_done, sig);
3549 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3550 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3551 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3552 exception_name(sig, buf, O_BUFLEN));
3553 }
3554 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3555 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3556 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3557 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3558 // No need to check this sig any longer
3559 sigaddset(&check_signal_done, sig);
3560 }
3561
3562 // Dump all the signal
3563 if (sigismember(&check_signal_done, sig)) {
3564 print_signal_handlers(tty, buf, O_BUFLEN);
3565 }
3566 }
3567
3568 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3569
3570 extern bool signal_name(int signo, char* buf, size_t len);
3571
3572 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3573 if (0 < exception_code && exception_code <= SIGRTMAX) {
3574 // signal
3575 if (!signal_name(exception_code, buf, size)) {
3576 jio_snprintf(buf, size, "SIG%d", exception_code);
3577 }
3578 return buf;
3579 } else {
3580 return NULL;
3581 }
3582 }
3583
3584 // this is called _before_ the most of global arguments have been parsed
3585 void os::init(void) {
3586 char dummy; /* used to get a guess on initial stack address */
3587 // first_hrtime = gethrtime();
3588
3589 // With BsdThreads the JavaMain thread pid (primordial thread)
3590 // is different than the pid of the java launcher thread.
3591 // So, on Bsd, the launcher thread pid is passed to the VM
3592 // via the sun.java.launcher.pid property.
3593 // Use this property instead of getpid() if it was correctly passed.
3594 // See bug 6351349.
3595 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3596
3597 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3598
3599 clock_tics_per_sec = CLK_TCK;
3600
3601 init_random(1234567);
3602
3603 ThreadCritical::initialize();
3604
3605 Bsd::set_page_size(getpagesize());
3606 if (Bsd::page_size() == -1) {
3607 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3608 strerror(errno)));
3609 }
3610 init_page_sizes((size_t) Bsd::page_size());
3611
3612 Bsd::initialize_system_info();
3613
3614 // _main_thread points to the thread that created/loaded the JVM.
3615 Bsd::_main_thread = pthread_self();
3616
3617 Bsd::clock_init();
3618 initial_time_count = javaTimeNanos();
3619
3620 #ifdef __APPLE__
3621 // XXXDARWIN
3622 // Work around the unaligned VM callbacks in hotspot's
3623 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3624 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3625 // alignment when doing symbol lookup. To work around this, we force early
3626 // binding of all symbols now, thus binding when alignment is known-good.
3627 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3628 #endif
3629 }
3630
3631 // To install functions for atexit system call
3632 extern "C" {
3633 static void perfMemory_exit_helper() {
3634 perfMemory_exit();
3635 }
3636 }
3637
3638 // this is called _after_ the global arguments have been parsed
3639 jint os::init_2(void)
3640 {
3641 // Allocate a single page and mark it as readable for safepoint polling
3642 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3643 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3644
3645 os::set_polling_page( polling_page );
3646
3647 #ifndef PRODUCT
3648 if(Verbose && PrintMiscellaneous)
3649 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3650 #endif
3651
3652 if (!UseMembar) {
3653 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3654 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3655 os::set_memory_serialize_page( mem_serialize_page );
3656
3657 #ifndef PRODUCT
3658 if(Verbose && PrintMiscellaneous)
3659 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3660 #endif
3661 }
3662
3663 // initialize suspend/resume support - must do this before signal_sets_init()
3664 if (SR_initialize() != 0) {
3665 perror("SR_initialize failed");
3666 return JNI_ERR;
3667 }
3668
3669 Bsd::signal_sets_init();
3670 Bsd::install_signal_handlers();
3671
3672 // Check minimum allowable stack size for thread creation and to initialize
3673 // the java system classes, including StackOverflowError - depends on page
3674 // size. Add a page for compiler2 recursion in main thread.
3675 // Add in 2*BytesPerWord times page size to account for VM stack during
3676 // class initialization depending on 32 or 64 bit VM.
3677 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3678 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3679 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3680
3681 size_t threadStackSizeInBytes = ThreadStackSize * K;
3682 if (threadStackSizeInBytes != 0 &&
3683 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3684 tty->print_cr("\nThe stack size specified is too small, "
3685 "Specify at least %dk",
3686 os::Bsd::min_stack_allowed/ K);
3687 return JNI_ERR;
3688 }
3689
3690 // Make the stack size a multiple of the page size so that
3691 // the yellow/red zones can be guarded.
3692 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3693 vm_page_size()));
3694
3695 if (MaxFDLimit) {
3696 // set the number of file descriptors to max. print out error
3697 // if getrlimit/setrlimit fails but continue regardless.
3698 struct rlimit nbr_files;
3699 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3700 if (status != 0) {
3701 if (PrintMiscellaneous && (Verbose || WizardMode))
3702 perror("os::init_2 getrlimit failed");
3703 } else {
3704 nbr_files.rlim_cur = nbr_files.rlim_max;
3705
3706 #ifdef __APPLE__
3707 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3708 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3709 // be used instead
3710 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3711 #endif
3712
3713 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3714 if (status != 0) {
3715 if (PrintMiscellaneous && (Verbose || WizardMode))
3716 perror("os::init_2 setrlimit failed");
3717 }
3718 }
3719 }
3720
3721 // at-exit methods are called in the reverse order of their registration.
3722 // atexit functions are called on return from main or as a result of a
3723 // call to exit(3C). There can be only 32 of these functions registered
3724 // and atexit() does not set errno.
3725
3726 if (PerfAllowAtExitRegistration) {
3727 // only register atexit functions if PerfAllowAtExitRegistration is set.
3728 // atexit functions can be delayed until process exit time, which
3729 // can be problematic for embedded VM situations. Embedded VMs should
3730 // call DestroyJavaVM() to assure that VM resources are released.
3731
3732 // note: perfMemory_exit_helper atexit function may be removed in
3733 // the future if the appropriate cleanup code can be added to the
3734 // VM_Exit VMOperation's doit method.
3735 if (atexit(perfMemory_exit_helper) != 0) {
3736 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3737 }
3738 }
3739
3740 // initialize thread priority policy
3741 prio_init();
3742
3743 #ifdef __APPLE__
3744 // dynamically link to objective c gc registration
3745 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3746 if (handleLibObjc != NULL) {
3747 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3748 }
3749 #endif
3750
3751 return JNI_OK;
3752 }
3753
3754 // Mark the polling page as unreadable
3755 void os::make_polling_page_unreadable(void) {
3756 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3757 fatal("Could not disable polling page");
3758 };
3759
3760 // Mark the polling page as readable
3761 void os::make_polling_page_readable(void) {
3762 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3763 fatal("Could not enable polling page");
3764 }
3765 };
3766
3767 int os::active_processor_count() {
3768 // User has overridden the number of active processors
3769 if (ActiveProcessorCount > 0) {
3770 if (PrintActiveCpus) {
3771 tty->print_cr("active_processor_count: "
3772 "active processor count set by user : %d",
3773 ActiveProcessorCount);
3774 }
3775 return ActiveProcessorCount;
3776 }
3777
3778 return _processor_count;
3779 }
3780
3781 void os::set_native_thread_name(const char *name) {
3782 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3783 // This is only supported in Snow Leopard and beyond
3784 if (name != NULL) {
3785 // Add a "Java: " prefix to the name
3786 char buf[MAXTHREADNAMESIZE];
3787 snprintf(buf, sizeof(buf), "Java: %s", name);
3788 pthread_setname_np(buf);
3789 }
3790 #endif
3791 }
3792
3793 bool os::distribute_processes(uint length, uint* distribution) {
3794 // Not yet implemented.
3795 return false;
3796 }
3797
3798 bool os::bind_to_processor(uint processor_id) {
3799 // Not yet implemented.
3800 return false;
3801 }
3802
3803 void os::SuspendedThreadTask::internal_do_task() {
3804 if (do_suspend(_thread->osthread())) {
3805 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3806 do_task(context);
3807 do_resume(_thread->osthread());
3808 }
3809 }
3810
3811 ///
3812 class PcFetcher : public os::SuspendedThreadTask {
3813 public:
3814 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3815 ExtendedPC result();
3816 protected:
3817 void do_task(const os::SuspendedThreadTaskContext& context);
3818 private:
3819 ExtendedPC _epc;
3820 };
3821
3822 ExtendedPC PcFetcher::result() {
3823 guarantee(is_done(), "task is not done yet.");
3824 return _epc;
3825 }
3826
3827 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3828 Thread* thread = context.thread();
3829 OSThread* osthread = thread->osthread();
3830 if (osthread->ucontext() != NULL) {
3831 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3832 } else {
3833 // NULL context is unexpected, double-check this is the VMThread
3834 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3835 }
3836 }
3837
3838 // Suspends the target using the signal mechanism and then grabs the PC before
3839 // resuming the target. Used by the flat-profiler only
3840 ExtendedPC os::get_thread_pc(Thread* thread) {
3841 // Make sure that it is called by the watcher for the VMThread
3842 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3843 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3844
3845 PcFetcher fetcher(thread);
3846 fetcher.run();
3847 return fetcher.result();
3848 }
3849
3850 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3851 {
3852 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3853 }
3854
3855 ////////////////////////////////////////////////////////////////////////////////
3856 // debug support
3857
3858 bool os::find(address addr, outputStream* st) {
3859 Dl_info dlinfo;
3860 memset(&dlinfo, 0, sizeof(dlinfo));
3861 if (dladdr(addr, &dlinfo) != 0) {
3862 st->print(PTR_FORMAT ": ", addr);
3863 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3864 st->print("%s+%#x", dlinfo.dli_sname,
3865 addr - (intptr_t)dlinfo.dli_saddr);
3866 } else if (dlinfo.dli_fbase != NULL) {
3867 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3868 } else {
3869 st->print("<absolute address>");
3870 }
3871 if (dlinfo.dli_fname != NULL) {
3872 st->print(" in %s", dlinfo.dli_fname);
3873 }
3874 if (dlinfo.dli_fbase != NULL) {
3875 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3876 }
3877 st->cr();
3878
3879 if (Verbose) {
3880 // decode some bytes around the PC
3881 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3882 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3883 address lowest = (address) dlinfo.dli_sname;
3884 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3885 if (begin < lowest) begin = lowest;
3886 Dl_info dlinfo2;
3887 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3888 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3889 end = (address) dlinfo2.dli_saddr;
3890 Disassembler::decode(begin, end, st);
3891 }
3892 return true;
3893 }
3894 return false;
3895 }
3896
3897 ////////////////////////////////////////////////////////////////////////////////
3898 // misc
3899
3900 // This does not do anything on Bsd. This is basically a hook for being
3901 // able to use structured exception handling (thread-local exception filters)
3902 // on, e.g., Win32.
3903 void
3904 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3905 JavaCallArguments* args, Thread* thread) {
3906 f(value, method, args, thread);
3907 }
3908
3909 void os::print_statistics() {
3910 }
3911
3912 int os::message_box(const char* title, const char* message) {
3913 int i;
3914 fdStream err(defaultStream::error_fd());
3915 for (i = 0; i < 78; i++) err.print_raw("=");
3916 err.cr();
3917 err.print_raw_cr(title);
3918 for (i = 0; i < 78; i++) err.print_raw("-");
3919 err.cr();
3920 err.print_raw_cr(message);
3921 for (i = 0; i < 78; i++) err.print_raw("=");
3922 err.cr();
3923
3924 char buf[16];
3925 // Prevent process from exiting upon "read error" without consuming all CPU
3926 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3927
3928 return buf[0] == 'y' || buf[0] == 'Y';
3929 }
3930
3931 int os::stat(const char *path, struct stat *sbuf) {
3932 char pathbuf[MAX_PATH];
3933 if (strlen(path) > MAX_PATH - 1) {
3934 errno = ENAMETOOLONG;
3935 return -1;
3936 }
3937 os::native_path(strcpy(pathbuf, path));
3938 return ::stat(pathbuf, sbuf);
3939 }
3940
3941 bool os::check_heap(bool force) {
3942 return true;
3943 }
3944
3945 ATTRIBUTE_PRINTF(3, 0)
3946 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3947 return ::vsnprintf(buf, count, format, args);
3948 }
3949
3950 // Is a (classpath) directory empty?
3951 bool os::dir_is_empty(const char* path) {
3952 DIR *dir = NULL;
3953 struct dirent *ptr;
3954
3955 dir = opendir(path);
3956 if (dir == NULL) return true;
3957
3958 /* Scan the directory */
3959 bool result = true;
3960 char buf[sizeof(struct dirent) + MAX_PATH];
3961 while (result && (ptr = ::readdir(dir)) != NULL) {
3962 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3963 result = false;
3964 }
3965 }
3966 closedir(dir);
3967 return result;
3968 }
3969
3970 // This code originates from JDK's sysOpen and open64_w
3971 // from src/solaris/hpi/src/system_md.c
3972
3973 #ifndef O_DELETE
3974 #define O_DELETE 0x10000
3975 #endif
3976
3977 // Open a file. Unlink the file immediately after open returns
3978 // if the specified oflag has the O_DELETE flag set.
3979 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3980
3981 int os::open(const char *path, int oflag, int mode) {
3982
3983 if (strlen(path) > MAX_PATH - 1) {
3984 errno = ENAMETOOLONG;
3985 return -1;
3986 }
3987 int fd;
3988 int o_delete = (oflag & O_DELETE);
3989 oflag = oflag & ~O_DELETE;
3990
3991 fd = ::open(path, oflag, mode);
3992 if (fd == -1) return -1;
3993
3994 //If the open succeeded, the file might still be a directory
3995 {
3996 struct stat buf;
3997 int ret = ::fstat(fd, &buf);
3998 int st_mode = buf.st_mode;
3999
4000 if (ret != -1) {
4001 if ((st_mode & S_IFMT) == S_IFDIR) {
4002 errno = EISDIR;
4003 ::close(fd);
4004 return -1;
4005 }
4006 } else {
4007 ::close(fd);
4008 return -1;
4009 }
4010 }
4011
4012 /*
4013 * All file descriptors that are opened in the JVM and not
4014 * specifically destined for a subprocess should have the
4015 * close-on-exec flag set. If we don't set it, then careless 3rd
4016 * party native code might fork and exec without closing all
4017 * appropriate file descriptors (e.g. as we do in closeDescriptors in
4018 * UNIXProcess.c), and this in turn might:
4019 *
4020 * - cause end-of-file to fail to be detected on some file
4021 * descriptors, resulting in mysterious hangs, or
4022 *
4023 * - might cause an fopen in the subprocess to fail on a system
4024 * suffering from bug 1085341.
4025 *
4026 * (Yes, the default setting of the close-on-exec flag is a Unix
4027 * design flaw)
4028 *
4029 * See:
4030 * 1085341: 32-bit stdio routines should support file descriptors >255
4031 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
4032 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
4033 */
4034 #ifdef FD_CLOEXEC
4035 {
4036 int flags = ::fcntl(fd, F_GETFD);
4037 if (flags != -1)
4038 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
4039 }
4040 #endif
4041
4042 if (o_delete != 0) {
4043 ::unlink(path);
4044 }
4045 return fd;
4046 }
4047
4048
4049 // create binary file, rewriting existing file if required
4050 int os::create_binary_file(const char* path, bool rewrite_existing) {
4051 int oflags = O_WRONLY | O_CREAT;
4052 if (!rewrite_existing) {
4053 oflags |= O_EXCL;
4054 }
4055 return ::open(path, oflags, S_IREAD | S_IWRITE);
4056 }
4057
4058 // return current position of file pointer
4059 jlong os::current_file_offset(int fd) {
4060 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
4061 }
4062
4063 // move file pointer to the specified offset
4064 jlong os::seek_to_file_offset(int fd, jlong offset) {
4065 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
4066 }
4067
4068 // This code originates from JDK's sysAvailable
4069 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
4070
4071 int os::available(int fd, jlong *bytes) {
4072 jlong cur, end;
4073 int mode;
4074 struct stat buf;
4075
4076 if (::fstat(fd, &buf) >= 0) {
4077 mode = buf.st_mode;
4078 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4079 /*
4080 * XXX: is the following call interruptible? If so, this might
4081 * need to go through the INTERRUPT_IO() wrapper as for other
4082 * blocking, interruptible calls in this file.
4083 */
4084 int n;
4085 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4086 *bytes = n;
4087 return 1;
4088 }
4089 }
4090 }
4091 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4092 return 0;
4093 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4094 return 0;
4095 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4096 return 0;
4097 }
4098 *bytes = end - cur;
4099 return 1;
4100 }
4101
4102 int os::socket_available(int fd, jint *pbytes) {
4103 if (fd < 0)
4104 return OS_OK;
4105
4106 int ret;
4107
4108 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4109
4110 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4111 // is expected to return 0 on failure and 1 on success to the jdk.
4112
4113 return (ret == OS_ERR) ? 0 : 1;
4114 }
4115
4116 // Map a block of memory.
4117 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4118 char *addr, size_t bytes, bool read_only,
4119 bool allow_exec) {
4120 int prot;
4121 int flags;
4122
4123 if (read_only) {
4124 prot = PROT_READ;
4125 flags = MAP_SHARED;
4126 } else {
4127 prot = PROT_READ | PROT_WRITE;
4128 flags = MAP_PRIVATE;
4129 }
4130
4131 if (allow_exec) {
4132 prot |= PROT_EXEC;
4133 }
4134
4135 if (addr != NULL) {
4136 flags |= MAP_FIXED;
4137 }
4138
4139 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4140 fd, file_offset);
4141 if (mapped_address == MAP_FAILED) {
4142 return NULL;
4143 }
4144 return mapped_address;
4145 }
4146
4147
4148 // Remap a block of memory.
4149 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4150 char *addr, size_t bytes, bool read_only,
4151 bool allow_exec) {
4152 // same as map_memory() on this OS
4153 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4154 allow_exec);
4155 }
4156
4157
4158 // Unmap a block of memory.
4159 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4160 return munmap(addr, bytes) == 0;
4161 }
4162
4163 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4164 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4165 // of a thread.
4166 //
4167 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4168 // the fast estimate available on the platform.
4169
4170 jlong os::current_thread_cpu_time() {
4171 #ifdef __APPLE__
4172 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4173 #else
4174 Unimplemented();
4175 return 0;
4176 #endif
4177 }
4178
4179 jlong os::thread_cpu_time(Thread* thread) {
4180 #ifdef __APPLE__
4181 return os::thread_cpu_time(thread, true /* user + sys */);
4182 #else
4183 Unimplemented();
4184 return 0;
4185 #endif
4186 }
4187
4188 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4189 #ifdef __APPLE__
4190 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4191 #else
4192 Unimplemented();
4193 return 0;
4194 #endif
4195 }
4196
4197 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4198 #ifdef __APPLE__
4199 struct thread_basic_info tinfo;
4200 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4201 kern_return_t kr;
4202 thread_t mach_thread;
4203
4204 mach_thread = thread->osthread()->thread_id();
4205 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4206 if (kr != KERN_SUCCESS)
4207 return -1;
4208
4209 if (user_sys_cpu_time) {
4210 jlong nanos;
4211 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4212 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4213 return nanos;
4214 } else {
4215 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4216 }
4217 #else
4218 Unimplemented();
4219 return 0;
4220 #endif
4221 }
4222
4223
4224 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4225 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4226 info_ptr->may_skip_backward = false; // elapsed time not wall time
4227 info_ptr->may_skip_forward = false; // elapsed time not wall time
4228 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4229 }
4230
4231 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4232 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4233 info_ptr->may_skip_backward = false; // elapsed time not wall time
4234 info_ptr->may_skip_forward = false; // elapsed time not wall time
4235 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4236 }
4237
4238 bool os::is_thread_cpu_time_supported() {
4239 #ifdef __APPLE__
4240 return true;
4241 #else
4242 return false;
4243 #endif
4244 }
4245
4246 // System loadavg support. Returns -1 if load average cannot be obtained.
4247 // Bsd doesn't yet have a (official) notion of processor sets,
4248 // so just return the system wide load average.
4249 int os::loadavg(double loadavg[], int nelem) {
4250 return ::getloadavg(loadavg, nelem);
4251 }
4252
4253 void os::pause() {
4254 char filename[MAX_PATH];
4255 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4256 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4257 } else {
4258 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4259 }
4260
4261 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4262 if (fd != -1) {
4263 struct stat buf;
4264 ::close(fd);
4265 while (::stat(filename, &buf) == 0) {
4266 (void)::poll(NULL, 0, 100);
4267 }
4268 } else {
4269 jio_fprintf(stderr,
4270 "Could not open pause file '%s', continuing immediately.\n", filename);
4271 }
4272 }
4273
4274
4275 // Refer to the comments in os_solaris.cpp park-unpark.
4276 //
4277 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4278 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4279 // For specifics regarding the bug see GLIBC BUGID 261237 :
4280 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4281 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4282 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4283 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4284 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4285 // and monitorenter when we're using 1-0 locking. All those operations may result in
4286 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4287 // of libpthread avoids the problem, but isn't practical.
4288 //
4289 // Possible remedies:
4290 //
4291 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4292 // This is palliative and probabilistic, however. If the thread is preempted
4293 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4294 // than the minimum period may have passed, and the abstime may be stale (in the
4295 // past) resultin in a hang. Using this technique reduces the odds of a hang
4296 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4297 //
4298 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4299 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4300 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4301 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4302 // thread.
4303 //
4304 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4305 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4306 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4307 // This also works well. In fact it avoids kernel-level scalability impediments
4308 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4309 // timers in a graceful fashion.
4310 //
4311 // 4. When the abstime value is in the past it appears that control returns
4312 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4313 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4314 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4315 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4316 // It may be possible to avoid reinitialization by checking the return
4317 // value from pthread_cond_timedwait(). In addition to reinitializing the
4318 // condvar we must establish the invariant that cond_signal() is only called
4319 // within critical sections protected by the adjunct mutex. This prevents
4320 // cond_signal() from "seeing" a condvar that's in the midst of being
4321 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4322 // desirable signal-after-unlock optimization that avoids futile context switching.
4323 //
4324 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4325 // structure when a condvar is used or initialized. cond_destroy() would
4326 // release the helper structure. Our reinitialize-after-timedwait fix
4327 // put excessive stress on malloc/free and locks protecting the c-heap.
4328 //
4329 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4330 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4331 // and only enabling the work-around for vulnerable environments.
4332
4333 // utility to compute the abstime argument to timedwait:
4334 // millis is the relative timeout time
4335 // abstime will be the absolute timeout time
4336 // TODO: replace compute_abstime() with unpackTime()
4337
4338 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4339 if (millis < 0) millis = 0;
4340 struct timeval now;
4341 int status = gettimeofday(&now, NULL);
4342 assert(status == 0, "gettimeofday");
4343 jlong seconds = millis / 1000;
4344 millis %= 1000;
4345 if (seconds > 50000000) { // see man cond_timedwait(3T)
4346 seconds = 50000000;
4347 }
4348 abstime->tv_sec = now.tv_sec + seconds;
4349 long usec = now.tv_usec + millis * 1000;
4350 if (usec >= 1000000) {
4351 abstime->tv_sec += 1;
4352 usec -= 1000000;
4353 }
4354 abstime->tv_nsec = usec * 1000;
4355 return abstime;
4356 }
4357
4358
4359 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4360 // Conceptually TryPark() should be equivalent to park(0).
4361
4362 int os::PlatformEvent::TryPark() {
4363 for (;;) {
4364 const int v = _Event ;
4365 guarantee ((v == 0) || (v == 1), "invariant") ;
4366 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4367 }
4368 }
4369
4370 void os::PlatformEvent::park() { // AKA "down()"
4371 // Invariant: Only the thread associated with the Event/PlatformEvent
4372 // may call park().
4373 // TODO: assert that _Assoc != NULL or _Assoc == Self
4374 int v ;
4375 for (;;) {
4376 v = _Event ;
4377 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4378 }
4379 guarantee (v >= 0, "invariant") ;
4380 if (v == 0) {
4381 // Do this the hard way by blocking ...
4382 int status = pthread_mutex_lock(_mutex);
4383 assert_status(status == 0, status, "mutex_lock");
4384 guarantee (_nParked == 0, "invariant") ;
4385 ++ _nParked ;
4386 while (_Event < 0) {
4387 status = pthread_cond_wait(_cond, _mutex);
4388 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4389 // Treat this the same as if the wait was interrupted
4390 if (status == ETIMEDOUT) { status = EINTR; }
4391 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4392 }
4393 -- _nParked ;
4394
4395 _Event = 0 ;
4396 status = pthread_mutex_unlock(_mutex);
4397 assert_status(status == 0, status, "mutex_unlock");
4398 // Paranoia to ensure our locked and lock-free paths interact
4399 // correctly with each other.
4400 OrderAccess::fence();
4401 }
4402 guarantee (_Event >= 0, "invariant") ;
4403 }
4404
4405 int os::PlatformEvent::park(jlong millis) {
4406 guarantee (_nParked == 0, "invariant") ;
4407
4408 int v ;
4409 for (;;) {
4410 v = _Event ;
4411 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4412 }
4413 guarantee (v >= 0, "invariant") ;
4414 if (v != 0) return OS_OK ;
4415
4416 // We do this the hard way, by blocking the thread.
4417 // Consider enforcing a minimum timeout value.
4418 struct timespec abst;
4419 compute_abstime(&abst, millis);
4420
4421 int ret = OS_TIMEOUT;
4422 int status = pthread_mutex_lock(_mutex);
4423 assert_status(status == 0, status, "mutex_lock");
4424 guarantee (_nParked == 0, "invariant") ;
4425 ++_nParked ;
4426
4427 // Object.wait(timo) will return because of
4428 // (a) notification
4429 // (b) timeout
4430 // (c) thread.interrupt
4431 //
4432 // Thread.interrupt and object.notify{All} both call Event::set.
4433 // That is, we treat thread.interrupt as a special case of notification.
4434 // The underlying Solaris implementation, cond_timedwait, admits
4435 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4436 // JVM from making those visible to Java code. As such, we must
4437 // filter out spurious wakeups. We assume all ETIME returns are valid.
4438 //
4439 // TODO: properly differentiate simultaneous notify+interrupt.
4440 // In that case, we should propagate the notify to another waiter.
4441
4442 while (_Event < 0) {
4443 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4444 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4445 pthread_cond_destroy (_cond);
4446 pthread_cond_init (_cond, NULL) ;
4447 }
4448 assert_status(status == 0 || status == EINTR ||
4449 status == ETIMEDOUT,
4450 status, "cond_timedwait");
4451 if (!FilterSpuriousWakeups) break ; // previous semantics
4452 if (status == ETIMEDOUT) break ;
4453 // We consume and ignore EINTR and spurious wakeups.
4454 }
4455 --_nParked ;
4456 if (_Event >= 0) {
4457 ret = OS_OK;
4458 }
4459 _Event = 0 ;
4460 status = pthread_mutex_unlock(_mutex);
4461 assert_status(status == 0, status, "mutex_unlock");
4462 assert (_nParked == 0, "invariant") ;
4463 // Paranoia to ensure our locked and lock-free paths interact
4464 // correctly with each other.
4465 OrderAccess::fence();
4466 return ret;
4467 }
4468
4469 void os::PlatformEvent::unpark() {
4470 // Transitions for _Event:
4471 // 0 :=> 1
4472 // 1 :=> 1
4473 // -1 :=> either 0 or 1; must signal target thread
4474 // That is, we can safely transition _Event from -1 to either
4475 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4476 // unpark() calls.
4477 // See also: "Semaphores in Plan 9" by Mullender & Cox
4478 //
4479 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4480 // that it will take two back-to-back park() calls for the owning
4481 // thread to block. This has the benefit of forcing a spurious return
4482 // from the first park() call after an unpark() call which will help
4483 // shake out uses of park() and unpark() without condition variables.
4484
4485 if (Atomic::xchg(1, &_Event) >= 0) return;
4486
4487 // Wait for the thread associated with the event to vacate
4488 int status = pthread_mutex_lock(_mutex);
4489 assert_status(status == 0, status, "mutex_lock");
4490 int AnyWaiters = _nParked;
4491 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4492 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4493 AnyWaiters = 0;
4494 pthread_cond_signal(_cond);
4495 }
4496 status = pthread_mutex_unlock(_mutex);
4497 assert_status(status == 0, status, "mutex_unlock");
4498 if (AnyWaiters != 0) {
4499 status = pthread_cond_signal(_cond);
4500 assert_status(status == 0, status, "cond_signal");
4501 }
4502
4503 // Note that we signal() _after dropping the lock for "immortal" Events.
4504 // This is safe and avoids a common class of futile wakeups. In rare
4505 // circumstances this can cause a thread to return prematurely from
4506 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4507 // simply re-test the condition and re-park itself.
4508 }
4509
4510
4511 // JSR166
4512 // -------------------------------------------------------
4513
4514 /*
4515 * The solaris and bsd implementations of park/unpark are fairly
4516 * conservative for now, but can be improved. They currently use a
4517 * mutex/condvar pair, plus a a count.
4518 * Park decrements count if > 0, else does a condvar wait. Unpark
4519 * sets count to 1 and signals condvar. Only one thread ever waits
4520 * on the condvar. Contention seen when trying to park implies that someone
4521 * is unparking you, so don't wait. And spurious returns are fine, so there
4522 * is no need to track notifications.
4523 */
4524
4525 #define MAX_SECS 100000000
4526 /*
4527 * This code is common to bsd and solaris and will be moved to a
4528 * common place in dolphin.
4529 *
4530 * The passed in time value is either a relative time in nanoseconds
4531 * or an absolute time in milliseconds. Either way it has to be unpacked
4532 * into suitable seconds and nanoseconds components and stored in the
4533 * given timespec structure.
4534 * Given time is a 64-bit value and the time_t used in the timespec is only
4535 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4536 * overflow if times way in the future are given. Further on Solaris versions
4537 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4538 * number of seconds, in abstime, is less than current_time + 100,000,000.
4539 * As it will be 28 years before "now + 100000000" will overflow we can
4540 * ignore overflow and just impose a hard-limit on seconds using the value
4541 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4542 * years from "now".
4543 */
4544
4545 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4546 assert (time > 0, "convertTime");
4547
4548 struct timeval now;
4549 int status = gettimeofday(&now, NULL);
4550 assert(status == 0, "gettimeofday");
4551
4552 time_t max_secs = now.tv_sec + MAX_SECS;
4553
4554 if (isAbsolute) {
4555 jlong secs = time / 1000;
4556 if (secs > max_secs) {
4557 absTime->tv_sec = max_secs;
4558 }
4559 else {
4560 absTime->tv_sec = secs;
4561 }
4562 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4563 }
4564 else {
4565 jlong secs = time / NANOSECS_PER_SEC;
4566 if (secs >= MAX_SECS) {
4567 absTime->tv_sec = max_secs;
4568 absTime->tv_nsec = 0;
4569 }
4570 else {
4571 absTime->tv_sec = now.tv_sec + secs;
4572 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4573 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4574 absTime->tv_nsec -= NANOSECS_PER_SEC;
4575 ++absTime->tv_sec; // note: this must be <= max_secs
4576 }
4577 }
4578 }
4579 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4580 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4581 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4582 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4583 }
4584
4585 void Parker::park(bool isAbsolute, jlong time) {
4586 // Ideally we'd do something useful while spinning, such
4587 // as calling unpackTime().
4588
4589 // Optional fast-path check:
4590 // Return immediately if a permit is available.
4591 // We depend on Atomic::xchg() having full barrier semantics
4592 // since we are doing a lock-free update to _counter.
4593 if (Atomic::xchg(0, &_counter) > 0) return;
4594
4595 Thread* thread = Thread::current();
4596 assert(thread->is_Java_thread(), "Must be JavaThread");
4597 JavaThread *jt = (JavaThread *)thread;
4598
4599 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4600 // Check interrupt before trying to wait
4601 if (Thread::is_interrupted(thread, false)) {
4602 return;
4603 }
4604
4605 // Next, demultiplex/decode time arguments
4606 struct timespec absTime;
4607 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4608 return;
4609 }
4610 if (time > 0) {
4611 unpackTime(&absTime, isAbsolute, time);
4612 }
4613
4614
4615 // Enter safepoint region
4616 // Beware of deadlocks such as 6317397.
4617 // The per-thread Parker:: mutex is a classic leaf-lock.
4618 // In particular a thread must never block on the Threads_lock while
4619 // holding the Parker:: mutex. If safepoints are pending both the
4620 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4621 ThreadBlockInVM tbivm(jt);
4622
4623 // Don't wait if cannot get lock since interference arises from
4624 // unblocking. Also. check interrupt before trying wait
4625 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4626 return;
4627 }
4628
4629 int status ;
4630 if (_counter > 0) { // no wait needed
4631 _counter = 0;
4632 status = pthread_mutex_unlock(_mutex);
4633 assert (status == 0, "invariant") ;
4634 // Paranoia to ensure our locked and lock-free paths interact
4635 // correctly with each other and Java-level accesses.
4636 OrderAccess::fence();
4637 return;
4638 }
4639
4640 #ifdef ASSERT
4641 // Don't catch signals while blocked; let the running threads have the signals.
4642 // (This allows a debugger to break into the running thread.)
4643 sigset_t oldsigs;
4644 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4645 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4646 #endif
4647
4648 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4649 jt->set_suspend_equivalent();
4650 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4651
4652 if (time == 0) {
4653 status = pthread_cond_wait (_cond, _mutex) ;
4654 } else {
4655 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4656 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4657 pthread_cond_destroy (_cond) ;
4658 pthread_cond_init (_cond, NULL);
4659 }
4660 }
4661 assert_status(status == 0 || status == EINTR ||
4662 status == ETIMEDOUT,
4663 status, "cond_timedwait");
4664
4665 #ifdef ASSERT
4666 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4667 #endif
4668
4669 _counter = 0 ;
4670 status = pthread_mutex_unlock(_mutex) ;
4671 assert_status(status == 0, status, "invariant") ;
4672 // Paranoia to ensure our locked and lock-free paths interact
4673 // correctly with each other and Java-level accesses.
4674 OrderAccess::fence();
4675
4676 // If externally suspended while waiting, re-suspend
4677 if (jt->handle_special_suspend_equivalent_condition()) {
4678 jt->java_suspend_self();
4679 }
4680 }
4681
4682 void Parker::unpark() {
4683 int s, status ;
4684 status = pthread_mutex_lock(_mutex);
4685 assert (status == 0, "invariant") ;
4686 s = _counter;
4687 _counter = 1;
4688 if (s < 1) {
4689 if (WorkAroundNPTLTimedWaitHang) {
4690 status = pthread_cond_signal (_cond) ;
4691 assert (status == 0, "invariant") ;
4692 status = pthread_mutex_unlock(_mutex);
4693 assert (status == 0, "invariant") ;
4694 } else {
4695 status = pthread_mutex_unlock(_mutex);
4696 assert (status == 0, "invariant") ;
4697 status = pthread_cond_signal (_cond) ;
4698 assert (status == 0, "invariant") ;
4699 }
4700 } else {
4701 pthread_mutex_unlock(_mutex);
4702 assert (status == 0, "invariant") ;
4703 }
4704 }
4705
4706
4707 /* Darwin has no "environ" in a dynamic library. */
4708 #ifdef __APPLE__
4709 #include <crt_externs.h>
4710 #define environ (*_NSGetEnviron())
4711 #else
4712 extern char** environ;
4713 #endif
4714
4715 // Run the specified command in a separate process. Return its exit value,
4716 // or -1 on failure (e.g. can't fork a new process).
4717 // Unlike system(), this function can be called from signal handler. It
4718 // doesn't block SIGINT et al.
4719 int os::fork_and_exec(char* cmd) {
4720 const char * argv[4] = {"sh", "-c", cmd, NULL};
4721
4722 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4723 // pthread_atfork handlers and reset pthread library. All we need is a
4724 // separate process to execve. Make a direct syscall to fork process.
4725 // On IA64 there's no fork syscall, we have to use fork() and hope for
4726 // the best...
4727 pid_t pid = fork();
4728
4729 if (pid < 0) {
4730 // fork failed
4731 return -1;
4732
4733 } else if (pid == 0) {
4734 // child process
4735
4736 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4737 // first to kill every thread on the thread list. Because this list is
4738 // not reset by fork() (see notes above), execve() will instead kill
4739 // every thread in the parent process. We know this is the only thread
4740 // in the new process, so make a system call directly.
4741 // IA64 should use normal execve() from glibc to match the glibc fork()
4742 // above.
4743 execve("/bin/sh", (char* const*)argv, environ);
4744
4745 // execve failed
4746 _exit(-1);
4747
4748 } else {
4749 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4750 // care about the actual exit code, for now.
4751
4752 int status;
4753
4754 // Wait for the child process to exit. This returns immediately if
4755 // the child has already exited. */
4756 while (waitpid(pid, &status, 0) < 0) {
4757 switch (errno) {
4758 case ECHILD: return 0;
4759 case EINTR: break;
4760 default: return -1;
4761 }
4762 }
4763
4764 if (WIFEXITED(status)) {
4765 // The child exited normally; get its exit code.
4766 return WEXITSTATUS(status);
4767 } else if (WIFSIGNALED(status)) {
4768 // The child exited because of a signal
4769 // The best value to return is 0x80 + signal number,
4770 // because that is what all Unix shells do, and because
4771 // it allows callers to distinguish between process exit and
4772 // process death by signal.
4773 return 0x80 + WTERMSIG(status);
4774 } else {
4775 // Unknown exit code; pass it through
4776 return status;
4777 }
4778 }
4779 }
4780
4781 // is_headless_jre()
4782 //
4783 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4784 // in order to report if we are running in a headless jre
4785 //
4786 // Since JDK8 xawt/libmawt.so was moved into the same directory
4787 // as libawt.so, and renamed libawt_xawt.so
4788 //
4789 bool os::is_headless_jre() {
4790 #ifdef __APPLE__
4791 // We no longer build headless-only on Mac OS X
4792 return false;
4793 #else
4794 struct stat statbuf;
4795 char buf[MAXPATHLEN];
4796 char libmawtpath[MAXPATHLEN];
4797 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4798 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4799 char *p;
4800
4801 // Get path to libjvm.so
4802 os::jvm_path(buf, sizeof(buf));
4803
4804 // Get rid of libjvm.so
4805 p = strrchr(buf, '/');
4806 if (p == NULL) return false;
4807 else *p = '\0';
4808
4809 // Get rid of client or server
4810 p = strrchr(buf, '/');
4811 if (p == NULL) return false;
4812 else *p = '\0';
4813
4814 // check xawt/libmawt.so
4815 strcpy(libmawtpath, buf);
4816 strcat(libmawtpath, xawtstr);
4817 if (::stat(libmawtpath, &statbuf) == 0) return false;
4818
4819 // check libawt_xawt.so
4820 strcpy(libmawtpath, buf);
4821 strcat(libmawtpath, new_xawtstr);
4822 if (::stat(libmawtpath, &statbuf) == 0) return false;
4823
4824 return true;
4825 #endif
4826 }
4827
4828 // Get the default path to the core file
4829 // Returns the length of the string
4830 int os::get_core_path(char* buffer, size_t bufferSize) {
4831 int n = jio_snprintf(buffer, bufferSize, "/cores");
4832
4833 // Truncate if theoretical string was longer than bufferSize
4834 n = MIN2(n, (int)bufferSize);
4835
4836 return n;
4837 }
4838
4839 #ifndef PRODUCT
4840 void TestReserveMemorySpecial_test() {
4841 // No tests available for this platform
4842 }
4843 #endif