1 /*
2 * Copyright (c) 1999, 2016, 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 "logging/log.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "memory/filemap.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_bsd.inline.hpp"
40 #include "os_share_bsd.hpp"
41 #include "prims/jniFastGetField.hpp"
42 #include "prims/jvm.h"
43 #include "prims/jvm_misc.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/atomic.hpp"
46 #include "runtime/extendedPC.hpp"
47 #include "runtime/globals.hpp"
48 #include "runtime/interfaceSupport.hpp"
49 #include "runtime/java.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/mutexLocker.hpp"
52 #include "runtime/objectMonitor.hpp"
53 #include "runtime/orderAccess.inline.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/perfMemory.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/statSampler.hpp"
58 #include "runtime/stubRoutines.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "runtime/threadCritical.hpp"
61 #include "runtime/timer.hpp"
62 #include "semaphore_bsd.hpp"
63 #include "services/attachListener.hpp"
64 #include "services/memTracker.hpp"
65 #include "services/runtimeService.hpp"
66 #include "utilities/decoder.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69 #include "utilities/growableArray.hpp"
70 #include "utilities/vmError.hpp"
71
72 // put OS-includes here
73 # include <sys/types.h>
74 # include <sys/mman.h>
75 # include <sys/stat.h>
76 # include <sys/select.h>
77 # include <pthread.h>
78 # include <signal.h>
79 # include <errno.h>
80 # include <dlfcn.h>
81 # include <stdio.h>
82 # include <unistd.h>
83 # include <sys/resource.h>
84 # include <pthread.h>
85 # include <sys/stat.h>
86 # include <sys/time.h>
87 # include <sys/times.h>
88 # include <sys/utsname.h>
89 # include <sys/socket.h>
90 # include <sys/wait.h>
91 # include <time.h>
92 # include <pwd.h>
93 # include <poll.h>
94 # include <semaphore.h>
95 # include <fcntl.h>
96 # include <string.h>
97 # include <sys/param.h>
98 # include <sys/sysctl.h>
99 # include <sys/ipc.h>
100 # include <sys/shm.h>
101 #ifndef __APPLE__
102 # include <link.h>
103 #endif
104 # include <stdint.h>
105 # include <inttypes.h>
106 # include <sys/ioctl.h>
107 # include <sys/syscall.h>
108
109 #if defined(__FreeBSD__) || defined(__NetBSD__)
110 #include <elf.h>
111 #endif
112
113 #ifdef __APPLE__
114 #include <mach/mach.h> // semaphore_* API
115 #include <mach-o/dyld.h>
116 #include <sys/proc_info.h>
117 #include <objc/objc-auto.h>
118 #endif
119
120 #ifndef MAP_ANONYMOUS
121 #define MAP_ANONYMOUS MAP_ANON
122 #endif
123
124 #define MAX_PATH (2 * K)
125
126 // for timer info max values which include all bits
127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
128
129 #define LARGEPAGES_BIT (1 << 6)
130
131 ////////////////////////////////////////////////////////////////////////////////
132 // global variables
133 julong os::Bsd::_physical_memory = 0;
134
135 #ifdef __APPLE__
136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
137 volatile uint64_t os::Bsd::_max_abstime = 0;
138 #else
139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
140 #endif
141 pthread_t os::Bsd::_main_thread;
142 int os::Bsd::_page_size = -1;
143
144 static jlong initial_time_count=0;
145
146 static int clock_tics_per_sec = 100;
147
148 // For diagnostics to print a message once. see run_periodic_checks
149 static sigset_t check_signal_done;
150 static bool check_signals = true;
151
152 static pid_t _initial_pid = 0;
153
154 // Signal number used to suspend/resume a thread
155
156 // do not use any signal number less than SIGSEGV, see 4355769
157 static int SR_signum = SIGUSR2;
158 sigset_t SR_sigset;
159
160
161 ////////////////////////////////////////////////////////////////////////////////
162 // utility functions
163
164 static int SR_initialize();
165 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
166
167 julong os::available_memory() {
168 return Bsd::available_memory();
169 }
170
171 // available here means free
172 julong os::Bsd::available_memory() {
173 uint64_t available = physical_memory() >> 2;
174 #ifdef __APPLE__
175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
176 vm_statistics64_data_t vmstat;
177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
178 (host_info64_t)&vmstat, &count);
179 assert(kerr == KERN_SUCCESS,
180 "host_statistics64 failed - check mach_host_self() and count");
181 if (kerr == KERN_SUCCESS) {
182 available = vmstat.free_count * os::vm_page_size();
183 }
184 #endif
185 return available;
186 }
187
188 julong os::physical_memory() {
189 return Bsd::physical_memory();
190 }
191
192 // Return true if user is running as root.
193
194 bool os::have_special_privileges() {
195 static bool init = false;
196 static bool privileges = false;
197 if (!init) {
198 privileges = (getuid() != geteuid()) || (getgid() != getegid());
199 init = true;
200 }
201 return privileges;
202 }
203
204
205
206 // Cpu architecture string
207 #if defined(ZERO)
208 static char cpu_arch[] = ZERO_LIBARCH;
209 #elif defined(IA64)
210 static char cpu_arch[] = "ia64";
211 #elif defined(IA32)
212 static char cpu_arch[] = "i386";
213 #elif defined(AMD64)
214 static char cpu_arch[] = "amd64";
215 #elif defined(ARM)
216 static char cpu_arch[] = "arm";
217 #elif defined(PPC32)
218 static char cpu_arch[] = "ppc";
219 #elif defined(SPARC)
220 #ifdef _LP64
221 static char cpu_arch[] = "sparcv9";
222 #else
223 static char cpu_arch[] = "sparc";
224 #endif
225 #else
226 #error Add appropriate cpu_arch setting
227 #endif
228
229 // Compiler variant
230 #ifdef COMPILER2
231 #define COMPILER_VARIANT "server"
232 #else
233 #define COMPILER_VARIANT "client"
234 #endif
235
236
237 void os::Bsd::initialize_system_info() {
238 int mib[2];
239 size_t len;
240 int cpu_val;
241 julong mem_val;
242
243 // get processors count via hw.ncpus sysctl
244 mib[0] = CTL_HW;
245 mib[1] = HW_NCPU;
246 len = sizeof(cpu_val);
247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
248 assert(len == sizeof(cpu_val), "unexpected data size");
249 set_processor_count(cpu_val);
250 } else {
251 set_processor_count(1); // fallback
252 }
253
254 // get physical memory via hw.memsize sysctl (hw.memsize is used
255 // since it returns a 64 bit value)
256 mib[0] = CTL_HW;
257
258 #if defined (HW_MEMSIZE) // Apple
259 mib[1] = HW_MEMSIZE;
260 #elif defined(HW_PHYSMEM) // Most of BSD
261 mib[1] = HW_PHYSMEM;
262 #elif defined(HW_REALMEM) // Old FreeBSD
263 mib[1] = HW_REALMEM;
264 #else
265 #error No ways to get physmem
266 #endif
267
268 len = sizeof(mem_val);
269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
270 assert(len == sizeof(mem_val), "unexpected data size");
271 _physical_memory = mem_val;
272 } else {
273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
274 }
275
276 #ifdef __OpenBSD__
277 {
278 // limit _physical_memory memory view on OpenBSD since
279 // datasize rlimit restricts us anyway.
280 struct rlimit limits;
281 getrlimit(RLIMIT_DATA, &limits);
282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
283 }
284 #endif
285 }
286
287 #ifdef __APPLE__
288 static const char *get_home() {
289 const char *home_dir = ::getenv("HOME");
290 if ((home_dir == NULL) || (*home_dir == '\0')) {
291 struct passwd *passwd_info = getpwuid(geteuid());
292 if (passwd_info != NULL) {
293 home_dir = passwd_info->pw_dir;
294 }
295 }
296
297 return home_dir;
298 }
299 #endif
300
301 void os::init_system_properties_values() {
302 // The next steps are taken in the product version:
303 //
304 // Obtain the JAVA_HOME value from the location of libjvm.so.
305 // This library should be located at:
306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
307 //
308 // If "/jre/lib/" appears at the right place in the path, then we
309 // assume libjvm.so is installed in a JDK and we use this path.
310 //
311 // Otherwise exit with message: "Could not create the Java virtual machine."
312 //
313 // The following extra steps are taken in the debugging version:
314 //
315 // If "/jre/lib/" does NOT appear at the right place in the path
316 // instead of exit check for $JAVA_HOME environment variable.
317 //
318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
319 // then we append a fake suffix "hotspot/libjvm.so" to this path so
320 // it looks like libjvm.so is installed there
321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
322 //
323 // Otherwise exit.
324 //
325 // Important note: if the location of libjvm.so changes this
326 // code needs to be changed accordingly.
327
328 // See ld(1):
329 // The linker uses the following search paths to locate required
330 // shared libraries:
331 // 1: ...
332 // ...
333 // 7: The default directories, normally /lib and /usr/lib.
334 #ifndef DEFAULT_LIBPATH
335 #define DEFAULT_LIBPATH "/lib:/usr/lib"
336 #endif
337
338 // Base path of extensions installed on the system.
339 #define SYS_EXT_DIR "/usr/java/packages"
340 #define EXTENSIONS_DIR "/lib/ext"
341
342 #ifndef __APPLE__
343
344 // Buffer that fits several sprintfs.
345 // Note that the space for the colon and the trailing null are provided
346 // by the nulls included by the sizeof operator.
347 const size_t bufsize =
348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
351
352 // sysclasspath, java_home, dll_dir
353 {
354 char *pslash;
355 os::jvm_path(buf, bufsize);
356
357 // Found the full path to libjvm.so.
358 // Now cut the path to <java_home>/jre if we can.
359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
360 pslash = strrchr(buf, '/');
361 if (pslash != NULL) {
362 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
363 }
364 Arguments::set_dll_dir(buf);
365
366 if (pslash != NULL) {
367 pslash = strrchr(buf, '/');
368 if (pslash != NULL) {
369 *pslash = '\0'; // Get rid of /<arch>.
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL) {
372 *pslash = '\0'; // Get rid of /lib.
373 }
374 }
375 }
376 Arguments::set_java_home(buf);
377 set_boot_path('/', ':');
378 }
379
380 // Where to look for native libraries.
381 //
382 // Note: Due to a legacy implementation, most of the library path
383 // is set in the launcher. This was to accomodate linking restrictions
384 // on legacy Bsd implementations (which are no longer supported).
385 // Eventually, all the library path setting will be done here.
386 //
387 // However, to prevent the proliferation of improperly built native
388 // libraries, the new path component /usr/java/packages is added here.
389 // Eventually, all the library path setting will be done here.
390 {
391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
392 // should always exist (until the legacy problem cited above is
393 // addressed).
394 const char *v = ::getenv("LD_LIBRARY_PATH");
395 const char *v_colon = ":";
396 if (v == NULL) { v = ""; v_colon = ""; }
397 // That's +1 for the colon and +1 for the trailing '\0'.
398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
399 strlen(v) + 1 +
400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
401 mtInternal);
402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
403 Arguments::set_library_path(ld_library_path);
404 FREE_C_HEAP_ARRAY(char, ld_library_path);
405 }
406
407 // Extensions directories.
408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
409 Arguments::set_ext_dirs(buf);
410
411 FREE_C_HEAP_ARRAY(char, buf);
412
413 #else // __APPLE__
414
415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
417
418 const char *user_home_dir = get_home();
419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
421 sizeof(SYS_EXTENSIONS_DIRS);
422
423 // Buffer that fits several sprintfs.
424 // Note that the space for the colon and the trailing null are provided
425 // by the nulls included by the sizeof operator.
426 const size_t bufsize =
427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
430
431 // sysclasspath, java_home, dll_dir
432 {
433 char *pslash;
434 os::jvm_path(buf, bufsize);
435
436 // Found the full path to libjvm.so.
437 // Now cut the path to <java_home>/jre if we can.
438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
439 pslash = strrchr(buf, '/');
440 if (pslash != NULL) {
441 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
442 }
443 #ifdef STATIC_BUILD
444 strcat(buf, "/lib");
445 #endif
446
447 Arguments::set_dll_dir(buf);
448
449 if (pslash != NULL) {
450 pslash = strrchr(buf, '/');
451 if (pslash != NULL) {
452 *pslash = '\0'; // Get rid of /lib.
453 }
454 }
455 Arguments::set_java_home(buf);
456 set_boot_path('/', ':');
457 }
458
459 // Where to look for native libraries.
460 //
461 // Note: Due to a legacy implementation, most of the library path
462 // is set in the launcher. This was to accomodate linking restrictions
463 // on legacy Bsd implementations (which are no longer supported).
464 // Eventually, all the library path setting will be done here.
465 //
466 // However, to prevent the proliferation of improperly built native
467 // libraries, the new path component /usr/java/packages is added here.
468 // Eventually, all the library path setting will be done here.
469 {
470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
471 // should always exist (until the legacy problem cited above is
472 // addressed).
473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
474 // can specify a directory inside an app wrapper
475 const char *l = ::getenv("JAVA_LIBRARY_PATH");
476 const char *l_colon = ":";
477 if (l == NULL) { l = ""; l_colon = ""; }
478
479 const char *v = ::getenv("DYLD_LIBRARY_PATH");
480 const char *v_colon = ":";
481 if (v == NULL) { v = ""; v_colon = ""; }
482
483 // Apple's Java6 has "." at the beginning of java.library.path.
484 // OpenJDK on Windows has "." at the end of java.library.path.
485 // OpenJDK on Linux and Solaris don't have "." in java.library.path
486 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
487 // "." is appended to the end of java.library.path. Yes, this
488 // could cause a change in behavior, but Apple's Java6 behavior
489 // can be achieved by putting "." at the beginning of the
490 // JAVA_LIBRARY_PATH environment variable.
491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
492 strlen(v) + 1 + strlen(l) + 1 +
493 system_ext_size + 3,
494 mtInternal);
495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
496 v, v_colon, l, l_colon, user_home_dir);
497 Arguments::set_library_path(ld_library_path);
498 FREE_C_HEAP_ARRAY(char, ld_library_path);
499 }
500
501 // Extensions directories.
502 //
503 // Note that the space for the colon and the trailing null are provided
504 // by the nulls included by the sizeof operator (so actually one byte more
505 // than necessary is allocated).
506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
507 user_home_dir, Arguments::get_java_home());
508 Arguments::set_ext_dirs(buf);
509
510 FREE_C_HEAP_ARRAY(char, buf);
511
512 #undef SYS_EXTENSIONS_DIR
513 #undef SYS_EXTENSIONS_DIRS
514
515 #endif // __APPLE__
516
517 #undef SYS_EXT_DIR
518 #undef EXTENSIONS_DIR
519 }
520
521 ////////////////////////////////////////////////////////////////////////////////
522 // breakpoint support
523
524 void os::breakpoint() {
525 BREAKPOINT;
526 }
527
528 extern "C" void breakpoint() {
529 // use debugger to set breakpoint here
530 }
531
532 ////////////////////////////////////////////////////////////////////////////////
533 // signal support
534
535 debug_only(static bool signal_sets_initialized = false);
536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
537
538 bool os::Bsd::is_sig_ignored(int sig) {
539 struct sigaction oact;
540 sigaction(sig, (struct sigaction*)NULL, &oact);
541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
542 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
544 return true;
545 } else {
546 return false;
547 }
548 }
549
550 void os::Bsd::signal_sets_init() {
551 // Should also have an assertion stating we are still single-threaded.
552 assert(!signal_sets_initialized, "Already initialized");
553 // Fill in signals that are necessarily unblocked for all threads in
554 // the VM. Currently, we unblock the following signals:
555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
556 // by -Xrs (=ReduceSignalUsage));
557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
559 // the dispositions or masks wrt these signals.
560 // Programs embedding the VM that want to use the above signals for their
561 // own purposes must, at this time, use the "-Xrs" option to prevent
562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
563 // (See bug 4345157, and other related bugs).
564 // In reality, though, unblocking these signals is really a nop, since
565 // these signals are not blocked by default.
566 sigemptyset(&unblocked_sigs);
567 sigemptyset(&allowdebug_blocked_sigs);
568 sigaddset(&unblocked_sigs, SIGILL);
569 sigaddset(&unblocked_sigs, SIGSEGV);
570 sigaddset(&unblocked_sigs, SIGBUS);
571 sigaddset(&unblocked_sigs, SIGFPE);
572 sigaddset(&unblocked_sigs, SR_signum);
573
574 if (!ReduceSignalUsage) {
575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
578 }
579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
582 }
583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
586 }
587 }
588 // Fill in signals that are blocked by all but the VM thread.
589 sigemptyset(&vm_sigs);
590 if (!ReduceSignalUsage) {
591 sigaddset(&vm_sigs, BREAK_SIGNAL);
592 }
593 debug_only(signal_sets_initialized = true);
594
595 }
596
597 // These are signals that are unblocked while a thread is running Java.
598 // (For some reason, they get blocked by default.)
599 sigset_t* os::Bsd::unblocked_signals() {
600 assert(signal_sets_initialized, "Not initialized");
601 return &unblocked_sigs;
602 }
603
604 // These are the signals that are blocked while a (non-VM) thread is
605 // running Java. Only the VM thread handles these signals.
606 sigset_t* os::Bsd::vm_signals() {
607 assert(signal_sets_initialized, "Not initialized");
608 return &vm_sigs;
609 }
610
611 // These are signals that are blocked during cond_wait to allow debugger in
612 sigset_t* os::Bsd::allowdebug_blocked_signals() {
613 assert(signal_sets_initialized, "Not initialized");
614 return &allowdebug_blocked_sigs;
615 }
616
617 void os::Bsd::hotspot_sigmask(Thread* thread) {
618
619 //Save caller's signal mask before setting VM signal mask
620 sigset_t caller_sigmask;
621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
622
623 OSThread* osthread = thread->osthread();
624 osthread->set_caller_sigmask(caller_sigmask);
625
626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
627
628 if (!ReduceSignalUsage) {
629 if (thread->is_VM_thread()) {
630 // Only the VM thread handles BREAK_SIGNAL ...
631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
632 } else {
633 // ... all other threads block BREAK_SIGNAL
634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
635 }
636 }
637 }
638
639
640 //////////////////////////////////////////////////////////////////////////////
641 // create new thread
642
643 #ifdef __APPLE__
644 // library handle for calling objc_registerThreadWithCollector()
645 // without static linking to the libobjc library
646 #define OBJC_LIB "/usr/lib/libobjc.dylib"
647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
648 typedef void (*objc_registerThreadWithCollector_t)();
649 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
650 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
651 #endif
652
653 #ifdef __APPLE__
654 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
655 // Additional thread_id used to correlate threads in SA
656 thread_identifier_info_data_t m_ident_info;
657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
658
659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
660 (thread_info_t) &m_ident_info, &count);
661
662 return m_ident_info.thread_id;
663 }
664 #endif
665
666 // Thread start routine for all newly created threads
667 static void *thread_native_entry(Thread *thread) {
668 // Try to randomize the cache line index of hot stack frames.
669 // This helps when threads of the same stack traces evict each other's
670 // cache lines. The threads can be either from the same JVM instance, or
671 // from different JVM instances. The benefit is especially true for
672 // processors with hyperthreading technology.
673 static int counter = 0;
674 int pid = os::current_process_id();
675 alloca(((pid ^ counter++) & 7) * 128);
676
677 thread->initialize_thread_current();
678
679 OSThread* osthread = thread->osthread();
680 Monitor* sync = osthread->startThread_lock();
681
682 osthread->set_thread_id(os::Bsd::gettid());
683
684 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
685 os::current_thread_id(), (uintx) pthread_self());
686
687 #ifdef __APPLE__
688 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
689 guarantee(unique_thread_id != 0, "unique thread id was not found");
690 osthread->set_unique_thread_id(unique_thread_id);
691 #endif
692 // initialize signal mask for this thread
693 os::Bsd::hotspot_sigmask(thread);
694
695 // initialize floating point control register
696 os::Bsd::init_thread_fpu_state();
697
698 #ifdef __APPLE__
699 // register thread with objc gc
700 if (objc_registerThreadWithCollectorFunction != NULL) {
701 objc_registerThreadWithCollectorFunction();
702 }
703 #endif
704
705 // handshaking with parent thread
706 {
707 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
708
709 // notify parent thread
710 osthread->set_state(INITIALIZED);
711 sync->notify_all();
712
713 // wait until os::start_thread()
714 while (osthread->get_state() == INITIALIZED) {
715 sync->wait(Mutex::_no_safepoint_check_flag);
716 }
717 }
718
719 // call one more level start routine
720 thread->run();
721
722 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
723 os::current_thread_id(), (uintx) pthread_self());
724
725 // If a thread has not deleted itself ("delete this") as part of its
726 // termination sequence, we have to ensure thread-local-storage is
727 // cleared before we actually terminate. No threads should ever be
728 // deleted asynchronously with respect to their termination.
729 if (Thread::current_or_null_safe() != NULL) {
730 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
731 thread->clear_thread_current();
732 }
733
734 return 0;
735 }
736
737 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
738 assert(thread->osthread() == NULL, "caller responsible");
739
740 // Allocate the OSThread object
741 OSThread* osthread = new OSThread(NULL, NULL);
742 if (osthread == NULL) {
743 return false;
744 }
745
746 // set the correct thread state
747 osthread->set_thread_type(thr_type);
748
749 // Initial state is ALLOCATED but not INITIALIZED
750 osthread->set_state(ALLOCATED);
751
752 thread->set_osthread(osthread);
753
754 // init thread attributes
755 pthread_attr_t attr;
756 pthread_attr_init(&attr);
757 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
758
759 // calculate stack size if it's not specified by caller
760 if (stack_size == 0) {
761 stack_size = os::Bsd::default_stack_size(thr_type);
762
763 switch (thr_type) {
764 case os::java_thread:
765 // Java threads use ThreadStackSize which default value can be
766 // changed with the flag -Xss
767 assert(JavaThread::stack_size_at_create() > 0, "this should be set");
768 stack_size = JavaThread::stack_size_at_create();
769 break;
770 case os::compiler_thread:
771 if (CompilerThreadStackSize > 0) {
772 stack_size = (size_t)(CompilerThreadStackSize * K);
773 break;
774 } // else fall through:
775 // use VMThreadStackSize if CompilerThreadStackSize is not defined
776 case os::vm_thread:
777 case os::pgc_thread:
778 case os::cgc_thread:
779 case os::watcher_thread:
780 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
781 break;
782 }
783 }
784
785 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
786 pthread_attr_setstacksize(&attr, stack_size);
787
788 ThreadState state;
789
790 {
791 pthread_t tid;
792 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
793
794 char buf[64];
795 if (ret == 0) {
796 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
797 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
798 } else {
799 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
800 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
801 }
802
803 pthread_attr_destroy(&attr);
804
805 if (ret != 0) {
806 // Need to clean up stuff we've allocated so far
807 thread->set_osthread(NULL);
808 delete osthread;
809 return false;
810 }
811
812 // Store pthread info into the OSThread
813 osthread->set_pthread_id(tid);
814
815 // Wait until child thread is either initialized or aborted
816 {
817 Monitor* sync_with_child = osthread->startThread_lock();
818 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
819 while ((state = osthread->get_state()) == ALLOCATED) {
820 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
821 }
822 }
823
824 }
825
826 // Aborted due to thread limit being reached
827 if (state == ZOMBIE) {
828 thread->set_osthread(NULL);
829 delete osthread;
830 return false;
831 }
832
833 // The thread is returned suspended (in state INITIALIZED),
834 // and is started higher up in the call chain
835 assert(state == INITIALIZED, "race condition");
836 return true;
837 }
838
839 /////////////////////////////////////////////////////////////////////////////
840 // attach existing thread
841
842 // bootstrap the main thread
843 bool os::create_main_thread(JavaThread* thread) {
844 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
845 return create_attached_thread(thread);
846 }
847
848 bool os::create_attached_thread(JavaThread* thread) {
849 #ifdef ASSERT
850 thread->verify_not_published();
851 #endif
852
853 // Allocate the OSThread object
854 OSThread* osthread = new OSThread(NULL, NULL);
855
856 if (osthread == NULL) {
857 return false;
858 }
859
860 osthread->set_thread_id(os::Bsd::gettid());
861
862 // Store pthread info into the OSThread
863 #ifdef __APPLE__
864 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
865 guarantee(unique_thread_id != 0, "just checking");
866 osthread->set_unique_thread_id(unique_thread_id);
867 #endif
868 osthread->set_pthread_id(::pthread_self());
869
870 // initialize floating point control register
871 os::Bsd::init_thread_fpu_state();
872
873 // Initial thread state is RUNNABLE
874 osthread->set_state(RUNNABLE);
875
876 thread->set_osthread(osthread);
877
878 // initialize signal mask for this thread
879 // and save the caller's signal mask
880 os::Bsd::hotspot_sigmask(thread);
881
882 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
883 os::current_thread_id(), (uintx) pthread_self());
884
885 return true;
886 }
887
888 void os::pd_start_thread(Thread* thread) {
889 OSThread * osthread = thread->osthread();
890 assert(osthread->get_state() != INITIALIZED, "just checking");
891 Monitor* sync_with_child = osthread->startThread_lock();
892 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
893 sync_with_child->notify();
894 }
895
896 // Free Bsd resources related to the OSThread
897 void os::free_thread(OSThread* osthread) {
898 assert(osthread != NULL, "osthread not set");
899
900 // We are told to free resources of the argument thread,
901 // but we can only really operate on the current thread.
902 assert(Thread::current()->osthread() == osthread,
903 "os::free_thread but not current thread");
904
905 // Restore caller's signal mask
906 sigset_t sigmask = osthread->caller_sigmask();
907 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
908
909 delete osthread;
910 }
911
912 ////////////////////////////////////////////////////////////////////////////////
913 // time support
914
915 // Time since start-up in seconds to a fine granularity.
916 // Used by VMSelfDestructTimer and the MemProfiler.
917 double os::elapsedTime() {
918
919 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
920 }
921
922 jlong os::elapsed_counter() {
923 return javaTimeNanos() - initial_time_count;
924 }
925
926 jlong os::elapsed_frequency() {
927 return NANOSECS_PER_SEC; // nanosecond resolution
928 }
929
930 bool os::supports_vtime() { return true; }
931 bool os::enable_vtime() { return false; }
932 bool os::vtime_enabled() { return false; }
933
934 double os::elapsedVTime() {
935 // better than nothing, but not much
936 return elapsedTime();
937 }
938
939 jlong os::javaTimeMillis() {
940 timeval time;
941 int status = gettimeofday(&time, NULL);
942 assert(status != -1, "bsd error");
943 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
944 }
945
946 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
947 timeval time;
948 int status = gettimeofday(&time, NULL);
949 assert(status != -1, "bsd error");
950 seconds = jlong(time.tv_sec);
951 nanos = jlong(time.tv_usec) * 1000;
952 }
953
954 #ifndef __APPLE__
955 #ifndef CLOCK_MONOTONIC
956 #define CLOCK_MONOTONIC (1)
957 #endif
958 #endif
959
960 #ifdef __APPLE__
961 void os::Bsd::clock_init() {
962 mach_timebase_info(&_timebase_info);
963 }
964 #else
965 void os::Bsd::clock_init() {
966 struct timespec res;
967 struct timespec tp;
968 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
969 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
970 // yes, monotonic clock is supported
971 _clock_gettime = ::clock_gettime;
972 }
973 }
974 #endif
975
976
977
978 #ifdef __APPLE__
979
980 jlong os::javaTimeNanos() {
981 const uint64_t tm = mach_absolute_time();
982 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
983 const uint64_t prev = Bsd::_max_abstime;
984 if (now <= prev) {
985 return prev; // same or retrograde time;
986 }
987 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
988 assert(obsv >= prev, "invariant"); // Monotonicity
989 // If the CAS succeeded then we're done and return "now".
990 // If the CAS failed and the observed value "obsv" is >= now then
991 // we should return "obsv". If the CAS failed and now > obsv > prv then
992 // some other thread raced this thread and installed a new value, in which case
993 // we could either (a) retry the entire operation, (b) retry trying to install now
994 // or (c) just return obsv. We use (c). No loop is required although in some cases
995 // we might discard a higher "now" value in deference to a slightly lower but freshly
996 // installed obsv value. That's entirely benign -- it admits no new orderings compared
997 // to (a) or (b) -- and greatly reduces coherence traffic.
998 // We might also condition (c) on the magnitude of the delta between obsv and now.
999 // Avoiding excessive CAS operations to hot RW locations is critical.
1000 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1001 return (prev == obsv) ? now : obsv;
1002 }
1003
1004 #else // __APPLE__
1005
1006 jlong os::javaTimeNanos() {
1007 if (os::supports_monotonic_clock()) {
1008 struct timespec tp;
1009 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1010 assert(status == 0, "gettime error");
1011 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1012 return result;
1013 } else {
1014 timeval time;
1015 int status = gettimeofday(&time, NULL);
1016 assert(status != -1, "bsd error");
1017 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1018 return 1000 * usecs;
1019 }
1020 }
1021
1022 #endif // __APPLE__
1023
1024 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1025 if (os::supports_monotonic_clock()) {
1026 info_ptr->max_value = ALL_64_BITS;
1027
1028 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1029 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1030 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1031 } else {
1032 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1033 info_ptr->max_value = ALL_64_BITS;
1034
1035 // gettimeofday is a real time clock so it skips
1036 info_ptr->may_skip_backward = true;
1037 info_ptr->may_skip_forward = true;
1038 }
1039
1040 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1041 }
1042
1043 // Return the real, user, and system times in seconds from an
1044 // arbitrary fixed point in the past.
1045 bool os::getTimesSecs(double* process_real_time,
1046 double* process_user_time,
1047 double* process_system_time) {
1048 struct tms ticks;
1049 clock_t real_ticks = times(&ticks);
1050
1051 if (real_ticks == (clock_t) (-1)) {
1052 return false;
1053 } else {
1054 double ticks_per_second = (double) clock_tics_per_sec;
1055 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1056 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1057 *process_real_time = ((double) real_ticks) / ticks_per_second;
1058
1059 return true;
1060 }
1061 }
1062
1063
1064 char * os::local_time_string(char *buf, size_t buflen) {
1065 struct tm t;
1066 time_t long_time;
1067 time(&long_time);
1068 localtime_r(&long_time, &t);
1069 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1070 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1071 t.tm_hour, t.tm_min, t.tm_sec);
1072 return buf;
1073 }
1074
1075 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1076 return localtime_r(clock, res);
1077 }
1078
1079 ////////////////////////////////////////////////////////////////////////////////
1080 // runtime exit support
1081
1082 // Note: os::shutdown() might be called very early during initialization, or
1083 // called from signal handler. Before adding something to os::shutdown(), make
1084 // sure it is async-safe and can handle partially initialized VM.
1085 void os::shutdown() {
1086
1087 // allow PerfMemory to attempt cleanup of any persistent resources
1088 perfMemory_exit();
1089
1090 // needs to remove object in file system
1091 AttachListener::abort();
1092
1093 // flush buffered output, finish log files
1094 ostream_abort();
1095
1096 // Check for abort hook
1097 abort_hook_t abort_hook = Arguments::abort_hook();
1098 if (abort_hook != NULL) {
1099 abort_hook();
1100 }
1101
1102 }
1103
1104 // Note: os::abort() might be called very early during initialization, or
1105 // called from signal handler. Before adding something to os::abort(), make
1106 // sure it is async-safe and can handle partially initialized VM.
1107 void os::abort(bool dump_core, void* siginfo, const void* context) {
1108 os::shutdown();
1109 if (dump_core) {
1110 #ifndef PRODUCT
1111 fdStream out(defaultStream::output_fd());
1112 out.print_raw("Current thread is ");
1113 char buf[16];
1114 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1115 out.print_raw_cr(buf);
1116 out.print_raw_cr("Dumping core ...");
1117 #endif
1118 ::abort(); // dump core
1119 }
1120
1121 ::exit(1);
1122 }
1123
1124 // Die immediately, no exit hook, no abort hook, no cleanup.
1125 void os::die() {
1126 // _exit() on BsdThreads only kills current thread
1127 ::abort();
1128 }
1129
1130 // This method is a copy of JDK's sysGetLastErrorString
1131 // from src/solaris/hpi/src/system_md.c
1132
1133 size_t os::lasterror(char *buf, size_t len) {
1134 if (errno == 0) return 0;
1135
1136 const char *s = os::strerror(errno);
1137 size_t n = ::strlen(s);
1138 if (n >= len) {
1139 n = len - 1;
1140 }
1141 ::strncpy(buf, s, n);
1142 buf[n] = '\0';
1143 return n;
1144 }
1145
1146 // Information of current thread in variety of formats
1147 pid_t os::Bsd::gettid() {
1148 int retval = -1;
1149
1150 #ifdef __APPLE__ //XNU kernel
1151 // despite the fact mach port is actually not a thread id use it
1152 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1153 retval = ::pthread_mach_thread_np(::pthread_self());
1154 guarantee(retval != 0, "just checking");
1155 return retval;
1156
1157 #else
1158 #ifdef __FreeBSD__
1159 retval = syscall(SYS_thr_self);
1160 #else
1161 #ifdef __OpenBSD__
1162 retval = syscall(SYS_getthrid);
1163 #else
1164 #ifdef __NetBSD__
1165 retval = (pid_t) syscall(SYS__lwp_self);
1166 #endif
1167 #endif
1168 #endif
1169 #endif
1170
1171 if (retval == -1) {
1172 return getpid();
1173 }
1174 }
1175
1176 intx os::current_thread_id() {
1177 #ifdef __APPLE__
1178 return (intx)::pthread_mach_thread_np(::pthread_self());
1179 #else
1180 return (intx)::pthread_self();
1181 #endif
1182 }
1183
1184 int os::current_process_id() {
1185
1186 // Under the old bsd thread library, bsd gives each thread
1187 // its own process id. Because of this each thread will return
1188 // a different pid if this method were to return the result
1189 // of getpid(2). Bsd provides no api that returns the pid
1190 // of the launcher thread for the vm. This implementation
1191 // returns a unique pid, the pid of the launcher thread
1192 // that starts the vm 'process'.
1193
1194 // Under the NPTL, getpid() returns the same pid as the
1195 // launcher thread rather than a unique pid per thread.
1196 // Use gettid() if you want the old pre NPTL behaviour.
1197
1198 // if you are looking for the result of a call to getpid() that
1199 // returns a unique pid for the calling thread, then look at the
1200 // OSThread::thread_id() method in osThread_bsd.hpp file
1201
1202 return (int)(_initial_pid ? _initial_pid : getpid());
1203 }
1204
1205 // DLL functions
1206
1207 #define JNI_LIB_PREFIX "lib"
1208 #ifdef __APPLE__
1209 #define JNI_LIB_SUFFIX ".dylib"
1210 #else
1211 #define JNI_LIB_SUFFIX ".so"
1212 #endif
1213
1214 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1215
1216 // This must be hard coded because it's the system's temporary
1217 // directory not the java application's temp directory, ala java.io.tmpdir.
1218 #ifdef __APPLE__
1219 // macosx has a secure per-user temporary directory
1220 char temp_path_storage[PATH_MAX];
1221 const char* os::get_temp_directory() {
1222 static char *temp_path = NULL;
1223 if (temp_path == NULL) {
1224 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1225 if (pathSize == 0 || pathSize > PATH_MAX) {
1226 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1227 }
1228 temp_path = temp_path_storage;
1229 }
1230 return temp_path;
1231 }
1232 #else // __APPLE__
1233 const char* os::get_temp_directory() { return "/tmp"; }
1234 #endif // __APPLE__
1235
1236 static bool file_exists(const char* filename) {
1237 struct stat statbuf;
1238 if (filename == NULL || strlen(filename) == 0) {
1239 return false;
1240 }
1241 return os::stat(filename, &statbuf) == 0;
1242 }
1243
1244 bool os::dll_build_name(char* buffer, size_t buflen,
1245 const char* pname, const char* fname) {
1246 bool retval = false;
1247 // Copied from libhpi
1248 const size_t pnamelen = pname ? strlen(pname) : 0;
1249
1250 // Return error on buffer overflow.
1251 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1252 return retval;
1253 }
1254
1255 if (pnamelen == 0) {
1256 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1257 retval = true;
1258 } else if (strchr(pname, *os::path_separator()) != NULL) {
1259 int n;
1260 char** pelements = split_path(pname, &n);
1261 if (pelements == NULL) {
1262 return false;
1263 }
1264 for (int i = 0; i < n; i++) {
1265 // Really shouldn't be NULL, but check can't hurt
1266 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1267 continue; // skip the empty path values
1268 }
1269 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1270 pelements[i], fname);
1271 if (file_exists(buffer)) {
1272 retval = true;
1273 break;
1274 }
1275 }
1276 // release the storage
1277 for (int i = 0; i < n; i++) {
1278 if (pelements[i] != NULL) {
1279 FREE_C_HEAP_ARRAY(char, pelements[i]);
1280 }
1281 }
1282 if (pelements != NULL) {
1283 FREE_C_HEAP_ARRAY(char*, pelements);
1284 }
1285 } else {
1286 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1287 retval = true;
1288 }
1289 return retval;
1290 }
1291
1292 // check if addr is inside libjvm.so
1293 bool os::address_is_in_vm(address addr) {
1294 static address libjvm_base_addr;
1295 Dl_info dlinfo;
1296
1297 if (libjvm_base_addr == NULL) {
1298 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1299 libjvm_base_addr = (address)dlinfo.dli_fbase;
1300 }
1301 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1302 }
1303
1304 if (dladdr((void *)addr, &dlinfo) != 0) {
1305 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1306 }
1307
1308 return false;
1309 }
1310
1311
1312 #define MACH_MAXSYMLEN 256
1313
1314 bool os::dll_address_to_function_name(address addr, char *buf,
1315 int buflen, int *offset,
1316 bool demangle) {
1317 // buf is not optional, but offset is optional
1318 assert(buf != NULL, "sanity check");
1319
1320 Dl_info dlinfo;
1321 char localbuf[MACH_MAXSYMLEN];
1322
1323 if (dladdr((void*)addr, &dlinfo) != 0) {
1324 // see if we have a matching symbol
1325 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1326 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1327 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1328 }
1329 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1330 return true;
1331 }
1332 // no matching symbol so try for just file info
1333 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1334 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1335 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1336 return true;
1337 }
1338 }
1339
1340 // Handle non-dynamic manually:
1341 if (dlinfo.dli_fbase != NULL &&
1342 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1343 dlinfo.dli_fbase)) {
1344 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1345 jio_snprintf(buf, buflen, "%s", localbuf);
1346 }
1347 return true;
1348 }
1349 }
1350 buf[0] = '\0';
1351 if (offset != NULL) *offset = -1;
1352 return false;
1353 }
1354
1355 // ported from solaris version
1356 bool os::dll_address_to_library_name(address addr, char* buf,
1357 int buflen, int* offset) {
1358 // buf is not optional, but offset is optional
1359 assert(buf != NULL, "sanity check");
1360
1361 Dl_info dlinfo;
1362
1363 if (dladdr((void*)addr, &dlinfo) != 0) {
1364 if (dlinfo.dli_fname != NULL) {
1365 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1366 }
1367 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1368 *offset = addr - (address)dlinfo.dli_fbase;
1369 }
1370 return true;
1371 }
1372
1373 buf[0] = '\0';
1374 if (offset) *offset = -1;
1375 return false;
1376 }
1377
1378 // Loads .dll/.so and
1379 // in case of error it checks if .dll/.so was built for the
1380 // same architecture as Hotspot is running on
1381
1382 #ifdef __APPLE__
1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1384 #ifdef STATIC_BUILD
1385 return os::get_default_process_handle();
1386 #else
1387 void * result= ::dlopen(filename, RTLD_LAZY);
1388 if (result != NULL) {
1389 // Successful loading
1390 return result;
1391 }
1392
1393 // Read system error message into ebuf
1394 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1395 ebuf[ebuflen-1]='\0';
1396
1397 return NULL;
1398 #endif // STATIC_BUILD
1399 }
1400 #else
1401 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1402 #ifdef STATIC_BUILD
1403 return os::get_default_process_handle();
1404 #else
1405 void * result= ::dlopen(filename, RTLD_LAZY);
1406 if (result != NULL) {
1407 // Successful loading
1408 return result;
1409 }
1410
1411 Elf32_Ehdr elf_head;
1412
1413 // Read system error message into ebuf
1414 // It may or may not be overwritten below
1415 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1416 ebuf[ebuflen-1]='\0';
1417 int diag_msg_max_length=ebuflen-strlen(ebuf);
1418 char* diag_msg_buf=ebuf+strlen(ebuf);
1419
1420 if (diag_msg_max_length==0) {
1421 // No more space in ebuf for additional diagnostics message
1422 return NULL;
1423 }
1424
1425
1426 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1427
1428 if (file_descriptor < 0) {
1429 // Can't open library, report dlerror() message
1430 return NULL;
1431 }
1432
1433 bool failed_to_read_elf_head=
1434 (sizeof(elf_head)!=
1435 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1436
1437 ::close(file_descriptor);
1438 if (failed_to_read_elf_head) {
1439 // file i/o error - report dlerror() msg
1440 return NULL;
1441 }
1442
1443 typedef struct {
1444 Elf32_Half code; // Actual value as defined in elf.h
1445 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1446 char elf_class; // 32 or 64 bit
1447 char endianess; // MSB or LSB
1448 char* name; // String representation
1449 } arch_t;
1450
1451 #ifndef EM_486
1452 #define EM_486 6 /* Intel 80486 */
1453 #endif
1454
1455 #ifndef EM_MIPS_RS3_LE
1456 #define EM_MIPS_RS3_LE 10 /* MIPS */
1457 #endif
1458
1459 #ifndef EM_PPC64
1460 #define EM_PPC64 21 /* PowerPC64 */
1461 #endif
1462
1463 #ifndef EM_S390
1464 #define EM_S390 22 /* IBM System/390 */
1465 #endif
1466
1467 #ifndef EM_IA_64
1468 #define EM_IA_64 50 /* HP/Intel IA-64 */
1469 #endif
1470
1471 #ifndef EM_X86_64
1472 #define EM_X86_64 62 /* AMD x86-64 */
1473 #endif
1474
1475 static const arch_t arch_array[]={
1476 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1477 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1478 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1479 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1480 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1481 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1482 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1483 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1484 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1485 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1486 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1487 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1488 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1489 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1490 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1491 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1492 };
1493
1494 #if (defined IA32)
1495 static Elf32_Half running_arch_code=EM_386;
1496 #elif (defined AMD64)
1497 static Elf32_Half running_arch_code=EM_X86_64;
1498 #elif (defined IA64)
1499 static Elf32_Half running_arch_code=EM_IA_64;
1500 #elif (defined __sparc) && (defined _LP64)
1501 static Elf32_Half running_arch_code=EM_SPARCV9;
1502 #elif (defined __sparc) && (!defined _LP64)
1503 static Elf32_Half running_arch_code=EM_SPARC;
1504 #elif (defined __powerpc64__)
1505 static Elf32_Half running_arch_code=EM_PPC64;
1506 #elif (defined __powerpc__)
1507 static Elf32_Half running_arch_code=EM_PPC;
1508 #elif (defined ARM)
1509 static Elf32_Half running_arch_code=EM_ARM;
1510 #elif (defined S390)
1511 static Elf32_Half running_arch_code=EM_S390;
1512 #elif (defined ALPHA)
1513 static Elf32_Half running_arch_code=EM_ALPHA;
1514 #elif (defined MIPSEL)
1515 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1516 #elif (defined PARISC)
1517 static Elf32_Half running_arch_code=EM_PARISC;
1518 #elif (defined MIPS)
1519 static Elf32_Half running_arch_code=EM_MIPS;
1520 #elif (defined M68K)
1521 static Elf32_Half running_arch_code=EM_68K;
1522 #else
1523 #error Method os::dll_load requires that one of following is defined:\
1524 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1525 #endif
1526
1527 // Identify compatability class for VM's architecture and library's architecture
1528 // Obtain string descriptions for architectures
1529
1530 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1531 int running_arch_index=-1;
1532
1533 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1534 if (running_arch_code == arch_array[i].code) {
1535 running_arch_index = i;
1536 }
1537 if (lib_arch.code == arch_array[i].code) {
1538 lib_arch.compat_class = arch_array[i].compat_class;
1539 lib_arch.name = arch_array[i].name;
1540 }
1541 }
1542
1543 assert(running_arch_index != -1,
1544 "Didn't find running architecture code (running_arch_code) in arch_array");
1545 if (running_arch_index == -1) {
1546 // Even though running architecture detection failed
1547 // we may still continue with reporting dlerror() message
1548 return NULL;
1549 }
1550
1551 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1552 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1553 return NULL;
1554 }
1555
1556 #ifndef S390
1557 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1558 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1559 return NULL;
1560 }
1561 #endif // !S390
1562
1563 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1564 if (lib_arch.name!=NULL) {
1565 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1566 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1567 lib_arch.name, arch_array[running_arch_index].name);
1568 } else {
1569 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1570 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1571 lib_arch.code,
1572 arch_array[running_arch_index].name);
1573 }
1574 }
1575
1576 return NULL;
1577 #endif // STATIC_BUILD
1578 }
1579 #endif // !__APPLE__
1580
1581 void* os::get_default_process_handle() {
1582 #ifdef __APPLE__
1583 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1584 // to avoid finding unexpected symbols on second (or later)
1585 // loads of a library.
1586 return (void*)::dlopen(NULL, RTLD_FIRST);
1587 #else
1588 return (void*)::dlopen(NULL, RTLD_LAZY);
1589 #endif
1590 }
1591
1592 // XXX: Do we need a lock around this as per Linux?
1593 void* os::dll_lookup(void* handle, const char* name) {
1594 return dlsym(handle, name);
1595 }
1596
1597 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1598 outputStream * out = (outputStream *) param;
1599 out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1600 return 0;
1601 }
1602
1603 void os::print_dll_info(outputStream *st) {
1604 st->print_cr("Dynamic libraries:");
1605 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1606 st->print_cr("Error: Cannot print dynamic libraries.");
1607 }
1608 }
1609
1610 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1611 #ifdef RTLD_DI_LINKMAP
1612 Dl_info dli;
1613 void *handle;
1614 Link_map *map;
1615 Link_map *p;
1616
1617 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1618 dli.dli_fname == NULL) {
1619 return 1;
1620 }
1621 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1622 if (handle == NULL) {
1623 return 1;
1624 }
1625 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1626 if (map == NULL) {
1627 dlclose(handle);
1628 return 1;
1629 }
1630
1631 while (map->l_prev != NULL)
1632 map = map->l_prev;
1633
1634 while (map != NULL) {
1635 // Value for top_address is returned as 0 since we don't have any information about module size
1636 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1637 dlclose(handle);
1638 return 1;
1639 }
1640 map = map->l_next;
1641 }
1642
1643 dlclose(handle);
1644 #elif defined(__APPLE__)
1645 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1646 // Value for top_address is returned as 0 since we don't have any information about module size
1647 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1648 return 1;
1649 }
1650 }
1651 return 0;
1652 #else
1653 return 1;
1654 #endif
1655 }
1656
1657 void os::get_summary_os_info(char* buf, size_t buflen) {
1658 // These buffers are small because we want this to be brief
1659 // and not use a lot of stack while generating the hs_err file.
1660 char os[100];
1661 size_t size = sizeof(os);
1662 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1663 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1664 #ifdef __APPLE__
1665 strncpy(os, "Darwin", sizeof(os));
1666 #elif __OpenBSD__
1667 strncpy(os, "OpenBSD", sizeof(os));
1668 #else
1669 strncpy(os, "BSD", sizeof(os));
1670 #endif
1671 }
1672
1673 char release[100];
1674 size = sizeof(release);
1675 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1676 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1677 // if error, leave blank
1678 strncpy(release, "", sizeof(release));
1679 }
1680 snprintf(buf, buflen, "%s %s", os, release);
1681 }
1682
1683 void os::print_os_info_brief(outputStream* st) {
1684 os::Posix::print_uname_info(st);
1685 }
1686
1687 void os::print_os_info(outputStream* st) {
1688 st->print("OS:");
1689
1690 os::Posix::print_uname_info(st);
1691
1692 os::Posix::print_rlimit_info(st);
1693
1694 os::Posix::print_load_average(st);
1695 }
1696
1697 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1698 // Nothing to do for now.
1699 }
1700
1701 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1702 unsigned int mhz;
1703 size_t size = sizeof(mhz);
1704 int mib[] = { CTL_HW, HW_CPU_FREQ };
1705 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1706 mhz = 1; // looks like an error but can be divided by
1707 } else {
1708 mhz /= 1000000; // reported in millions
1709 }
1710
1711 char model[100];
1712 size = sizeof(model);
1713 int mib_model[] = { CTL_HW, HW_MODEL };
1714 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1715 strncpy(model, cpu_arch, sizeof(model));
1716 }
1717
1718 char machine[100];
1719 size = sizeof(machine);
1720 int mib_machine[] = { CTL_HW, HW_MACHINE };
1721 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1722 strncpy(machine, "", sizeof(machine));
1723 }
1724
1725 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1726 }
1727
1728 void os::print_memory_info(outputStream* st) {
1729
1730 st->print("Memory:");
1731 st->print(" %dk page", os::vm_page_size()>>10);
1732
1733 st->print(", physical " UINT64_FORMAT "k",
1734 os::physical_memory() >> 10);
1735 st->print("(" UINT64_FORMAT "k free)",
1736 os::available_memory() >> 10);
1737 st->cr();
1738 }
1739
1740 static void print_signal_handler(outputStream* st, int sig,
1741 char* buf, size_t buflen);
1742
1743 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1744 st->print_cr("Signal Handlers:");
1745 print_signal_handler(st, SIGSEGV, buf, buflen);
1746 print_signal_handler(st, SIGBUS , buf, buflen);
1747 print_signal_handler(st, SIGFPE , buf, buflen);
1748 print_signal_handler(st, SIGPIPE, buf, buflen);
1749 print_signal_handler(st, SIGXFSZ, buf, buflen);
1750 print_signal_handler(st, SIGILL , buf, buflen);
1751 print_signal_handler(st, SR_signum, buf, buflen);
1752 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1753 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1754 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1755 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1756 }
1757
1758 static char saved_jvm_path[MAXPATHLEN] = {0};
1759
1760 // Find the full path to the current module, libjvm
1761 void os::jvm_path(char *buf, jint buflen) {
1762 // Error checking.
1763 if (buflen < MAXPATHLEN) {
1764 assert(false, "must use a large-enough buffer");
1765 buf[0] = '\0';
1766 return;
1767 }
1768 // Lazy resolve the path to current module.
1769 if (saved_jvm_path[0] != 0) {
1770 strcpy(buf, saved_jvm_path);
1771 return;
1772 }
1773
1774 char dli_fname[MAXPATHLEN];
1775 bool ret = dll_address_to_library_name(
1776 CAST_FROM_FN_PTR(address, os::jvm_path),
1777 dli_fname, sizeof(dli_fname), NULL);
1778 assert(ret, "cannot locate libjvm");
1779 char *rp = NULL;
1780 if (ret && dli_fname[0] != '\0') {
1781 rp = realpath(dli_fname, buf);
1782 }
1783 if (rp == NULL) {
1784 return;
1785 }
1786
1787 if (Arguments::sun_java_launcher_is_altjvm()) {
1788 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1789 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1790 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1791 // appears at the right place in the string, then assume we are
1792 // installed in a JDK and we're done. Otherwise, check for a
1793 // JAVA_HOME environment variable and construct a path to the JVM
1794 // being overridden.
1795
1796 const char *p = buf + strlen(buf) - 1;
1797 for (int count = 0; p > buf && count < 5; ++count) {
1798 for (--p; p > buf && *p != '/'; --p)
1799 /* empty */ ;
1800 }
1801
1802 if (strncmp(p, "/jre/lib/", 9) != 0) {
1803 // Look for JAVA_HOME in the environment.
1804 char* java_home_var = ::getenv("JAVA_HOME");
1805 if (java_home_var != NULL && java_home_var[0] != 0) {
1806 char* jrelib_p;
1807 int len;
1808
1809 // Check the current module name "libjvm"
1810 p = strrchr(buf, '/');
1811 assert(strstr(p, "/libjvm") == p, "invalid library name");
1812
1813 rp = realpath(java_home_var, buf);
1814 if (rp == NULL) {
1815 return;
1816 }
1817
1818 // determine if this is a legacy image or modules image
1819 // modules image doesn't have "jre" subdirectory
1820 len = strlen(buf);
1821 assert(len < buflen, "Ran out of buffer space");
1822 jrelib_p = buf + len;
1823
1824 // Add the appropriate library subdir
1825 snprintf(jrelib_p, buflen-len, "/jre/lib");
1826 if (0 != access(buf, F_OK)) {
1827 snprintf(jrelib_p, buflen-len, "/lib");
1828 }
1829
1830 // Add the appropriate client or server subdir
1831 len = strlen(buf);
1832 jrelib_p = buf + len;
1833 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1834 if (0 != access(buf, F_OK)) {
1835 snprintf(jrelib_p, buflen-len, "%s", "");
1836 }
1837
1838 // If the path exists within JAVA_HOME, add the JVM library name
1839 // to complete the path to JVM being overridden. Otherwise fallback
1840 // to the path to the current library.
1841 if (0 == access(buf, F_OK)) {
1842 // Use current module name "libjvm"
1843 len = strlen(buf);
1844 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1845 } else {
1846 // Fall back to path of current library
1847 rp = realpath(dli_fname, buf);
1848 if (rp == NULL) {
1849 return;
1850 }
1851 }
1852 }
1853 }
1854 }
1855
1856 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1857 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1858 }
1859
1860 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1861 // no prefix required, not even "_"
1862 }
1863
1864 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1865 // no suffix required
1866 }
1867
1868 ////////////////////////////////////////////////////////////////////////////////
1869 // sun.misc.Signal support
1870
1871 static volatile jint sigint_count = 0;
1872
1873 static void UserHandler(int sig, void *siginfo, void *context) {
1874 // 4511530 - sem_post is serialized and handled by the manager thread. When
1875 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1876 // don't want to flood the manager thread with sem_post requests.
1877 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1878 return;
1879 }
1880
1881 // Ctrl-C is pressed during error reporting, likely because the error
1882 // handler fails to abort. Let VM die immediately.
1883 if (sig == SIGINT && is_error_reported()) {
1884 os::die();
1885 }
1886
1887 os::signal_notify(sig);
1888 }
1889
1890 void* os::user_handler() {
1891 return CAST_FROM_FN_PTR(void*, UserHandler);
1892 }
1893
1894 extern "C" {
1895 typedef void (*sa_handler_t)(int);
1896 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1897 }
1898
1899 void* os::signal(int signal_number, void* handler) {
1900 struct sigaction sigAct, oldSigAct;
1901
1902 sigfillset(&(sigAct.sa_mask));
1903 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1904 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1905
1906 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1907 // -1 means registration failed
1908 return (void *)-1;
1909 }
1910
1911 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1912 }
1913
1914 void os::signal_raise(int signal_number) {
1915 ::raise(signal_number);
1916 }
1917
1918 // The following code is moved from os.cpp for making this
1919 // code platform specific, which it is by its very nature.
1920
1921 // Will be modified when max signal is changed to be dynamic
1922 int os::sigexitnum_pd() {
1923 return NSIG;
1924 }
1925
1926 // a counter for each possible signal value
1927 static volatile jint pending_signals[NSIG+1] = { 0 };
1928
1929 // Bsd(POSIX) specific hand shaking semaphore.
1930 #ifdef __APPLE__
1931 typedef semaphore_t os_semaphore_t;
1932
1933 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1934 #define SEM_WAIT(sem) semaphore_wait(sem)
1935 #define SEM_POST(sem) semaphore_signal(sem)
1936 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1937 #else
1938 typedef sem_t os_semaphore_t;
1939
1940 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1941 #define SEM_WAIT(sem) sem_wait(&sem)
1942 #define SEM_POST(sem) sem_post(&sem)
1943 #define SEM_DESTROY(sem) sem_destroy(&sem)
1944 #endif
1945
1946 #ifdef __APPLE__
1947 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
1948
1949 static const char* sem_init_strerror(kern_return_t value) {
1950 switch (value) {
1951 case KERN_INVALID_ARGUMENT: return "Invalid argument";
1952 case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
1953 default: return "Unknown";
1954 }
1955 }
1956
1957 OSXSemaphore::OSXSemaphore(uint value) {
1958 kern_return_t ret = SEM_INIT(_semaphore, value);
1959
1960 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
1961 }
1962
1963 OSXSemaphore::~OSXSemaphore() {
1964 SEM_DESTROY(_semaphore);
1965 }
1966
1967 void OSXSemaphore::signal(uint count) {
1968 for (uint i = 0; i < count; i++) {
1969 kern_return_t ret = SEM_POST(_semaphore);
1970
1971 assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
1972 }
1973 }
1974
1975 void OSXSemaphore::wait() {
1976 kern_return_t ret;
1977 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
1978 // Semaphore was interrupted. Retry.
1979 }
1980 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
1981 }
1982
1983 jlong OSXSemaphore::currenttime() {
1984 struct timeval tv;
1985 gettimeofday(&tv, NULL);
1986 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1987 }
1988
1989 bool OSXSemaphore::trywait() {
1990 return timedwait(0, 0);
1991 }
1992
1993 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
1994 kern_return_t kr = KERN_ABORTED;
1995 mach_timespec_t waitspec;
1996 waitspec.tv_sec = sec;
1997 waitspec.tv_nsec = nsec;
1998
1999 jlong starttime = currenttime();
2000
2001 kr = semaphore_timedwait(_semaphore, waitspec);
2002 while (kr == KERN_ABORTED) {
2003 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
2004
2005 jlong current = currenttime();
2006 jlong passedtime = current - starttime;
2007
2008 if (passedtime >= totalwait) {
2009 waitspec.tv_sec = 0;
2010 waitspec.tv_nsec = 0;
2011 } else {
2012 jlong waittime = totalwait - (current - starttime);
2013 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2014 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2015 }
2016
2017 kr = semaphore_timedwait(_semaphore, waitspec);
2018 }
2019
2020 return kr == KERN_SUCCESS;
2021 }
2022
2023 #else
2024 // Use POSIX implementation of semaphores.
2025
2026 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
2027 struct timespec ts;
2028 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2029
2030 return ts;
2031 }
2032
2033 #endif // __APPLE__
2034
2035 static os_semaphore_t sig_sem;
2036
2037 #ifdef __APPLE__
2038 static OSXSemaphore sr_semaphore;
2039 #else
2040 static PosixSemaphore sr_semaphore;
2041 #endif
2042
2043 void os::signal_init_pd() {
2044 // Initialize signal structures
2045 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2046
2047 // Initialize signal semaphore
2048 ::SEM_INIT(sig_sem, 0);
2049 }
2050
2051 void os::signal_notify(int sig) {
2052 Atomic::inc(&pending_signals[sig]);
2053 ::SEM_POST(sig_sem);
2054 }
2055
2056 static int check_pending_signals(bool wait) {
2057 Atomic::store(0, &sigint_count);
2058 for (;;) {
2059 for (int i = 0; i < NSIG + 1; i++) {
2060 jint n = pending_signals[i];
2061 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2062 return i;
2063 }
2064 }
2065 if (!wait) {
2066 return -1;
2067 }
2068 JavaThread *thread = JavaThread::current();
2069 ThreadBlockInVM tbivm(thread);
2070
2071 bool threadIsSuspended;
2072 do {
2073 thread->set_suspend_equivalent();
2074 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2075 ::SEM_WAIT(sig_sem);
2076
2077 // were we externally suspended while we were waiting?
2078 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2079 if (threadIsSuspended) {
2080 // The semaphore has been incremented, but while we were waiting
2081 // another thread suspended us. We don't want to continue running
2082 // while suspended because that would surprise the thread that
2083 // suspended us.
2084 ::SEM_POST(sig_sem);
2085
2086 thread->java_suspend_self();
2087 }
2088 } while (threadIsSuspended);
2089 }
2090 }
2091
2092 int os::signal_lookup() {
2093 return check_pending_signals(false);
2094 }
2095
2096 int os::signal_wait() {
2097 return check_pending_signals(true);
2098 }
2099
2100 ////////////////////////////////////////////////////////////////////////////////
2101 // Virtual Memory
2102
2103 int os::vm_page_size() {
2104 // Seems redundant as all get out
2105 assert(os::Bsd::page_size() != -1, "must call os::init");
2106 return os::Bsd::page_size();
2107 }
2108
2109 // Solaris allocates memory by pages.
2110 int os::vm_allocation_granularity() {
2111 assert(os::Bsd::page_size() != -1, "must call os::init");
2112 return os::Bsd::page_size();
2113 }
2114
2115 // Rationale behind this function:
2116 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2117 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2118 // samples for JITted code. Here we create private executable mapping over the code cache
2119 // and then we can use standard (well, almost, as mapping can change) way to provide
2120 // info for the reporting script by storing timestamp and location of symbol
2121 void bsd_wrap_code(char* base, size_t size) {
2122 static volatile jint cnt = 0;
2123
2124 if (!UseOprofile) {
2125 return;
2126 }
2127
2128 char buf[PATH_MAX + 1];
2129 int num = Atomic::add(1, &cnt);
2130
2131 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2132 os::get_temp_directory(), os::current_process_id(), num);
2133 unlink(buf);
2134
2135 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2136
2137 if (fd != -1) {
2138 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2139 if (rv != (off_t)-1) {
2140 if (::write(fd, "", 1) == 1) {
2141 mmap(base, size,
2142 PROT_READ|PROT_WRITE|PROT_EXEC,
2143 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2144 }
2145 }
2146 ::close(fd);
2147 unlink(buf);
2148 }
2149 }
2150
2151 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2152 int err) {
2153 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2154 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2155 os::errno_name(err), err);
2156 }
2157
2158 // NOTE: Bsd kernel does not really reserve the pages for us.
2159 // All it does is to check if there are enough free pages
2160 // left at the time of mmap(). This could be a potential
2161 // problem.
2162 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2163 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2164 #ifdef __OpenBSD__
2165 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2166 if (::mprotect(addr, size, prot) == 0) {
2167 return true;
2168 }
2169 #else
2170 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2171 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2172 if (res != (uintptr_t) MAP_FAILED) {
2173 return true;
2174 }
2175 #endif
2176
2177 // Warn about any commit errors we see in non-product builds just
2178 // in case mmap() doesn't work as described on the man page.
2179 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2180
2181 return false;
2182 }
2183
2184 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2185 bool exec) {
2186 // alignment_hint is ignored on this OS
2187 return pd_commit_memory(addr, size, exec);
2188 }
2189
2190 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2191 const char* mesg) {
2192 assert(mesg != NULL, "mesg must be specified");
2193 if (!pd_commit_memory(addr, size, exec)) {
2194 // add extra info in product mode for vm_exit_out_of_memory():
2195 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2196 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
2197 }
2198 }
2199
2200 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2201 size_t alignment_hint, bool exec,
2202 const char* mesg) {
2203 // alignment_hint is ignored on this OS
2204 pd_commit_memory_or_exit(addr, size, exec, mesg);
2205 }
2206
2207 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2208 }
2209
2210 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2211 ::madvise(addr, bytes, MADV_DONTNEED);
2212 }
2213
2214 void os::numa_make_global(char *addr, size_t bytes) {
2215 }
2216
2217 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2218 }
2219
2220 bool os::numa_topology_changed() { return false; }
2221
2222 size_t os::numa_get_groups_num() {
2223 return 1;
2224 }
2225
2226 int os::numa_get_group_id() {
2227 return 0;
2228 }
2229
2230 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2231 if (size > 0) {
2232 ids[0] = 0;
2233 return 1;
2234 }
2235 return 0;
2236 }
2237
2238 bool os::get_page_info(char *start, page_info* info) {
2239 return false;
2240 }
2241
2242 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2243 return end;
2244 }
2245
2246
2247 bool os::pd_uncommit_memory(char* addr, size_t size) {
2248 #ifdef __OpenBSD__
2249 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2250 return ::mprotect(addr, size, PROT_NONE) == 0;
2251 #else
2252 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2253 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2254 return res != (uintptr_t) MAP_FAILED;
2255 #endif
2256 }
2257
2258 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2259 return os::commit_memory(addr, size, !ExecMem);
2260 }
2261
2262 // If this is a growable mapping, remove the guard pages entirely by
2263 // munmap()ping them. If not, just call uncommit_memory().
2264 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2265 return os::uncommit_memory(addr, size);
2266 }
2267
2268 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2269 // at 'requested_addr'. If there are existing memory mappings at the same
2270 // location, however, they will be overwritten. If 'fixed' is false,
2271 // 'requested_addr' is only treated as a hint, the return value may or
2272 // may not start from the requested address. Unlike Bsd mmap(), this
2273 // function returns NULL to indicate failure.
2274 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2275 char * addr;
2276 int flags;
2277
2278 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2279 if (fixed) {
2280 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2281 flags |= MAP_FIXED;
2282 }
2283
2284 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2285 // touch an uncommitted page. Otherwise, the read/write might
2286 // succeed if we have enough swap space to back the physical page.
2287 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2288 flags, -1, 0);
2289
2290 return addr == MAP_FAILED ? NULL : addr;
2291 }
2292
2293 static int anon_munmap(char * addr, size_t size) {
2294 return ::munmap(addr, size) == 0;
2295 }
2296
2297 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2298 size_t alignment_hint) {
2299 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2300 }
2301
2302 bool os::pd_release_memory(char* addr, size_t size) {
2303 return anon_munmap(addr, size);
2304 }
2305
2306 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2307 // Bsd wants the mprotect address argument to be page aligned.
2308 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2309
2310 // According to SUSv3, mprotect() should only be used with mappings
2311 // established by mmap(), and mmap() always maps whole pages. Unaligned
2312 // 'addr' likely indicates problem in the VM (e.g. trying to change
2313 // protection of malloc'ed or statically allocated memory). Check the
2314 // caller if you hit this assert.
2315 assert(addr == bottom, "sanity check");
2316
2317 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2318 return ::mprotect(bottom, size, prot) == 0;
2319 }
2320
2321 // Set protections specified
2322 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2323 bool is_committed) {
2324 unsigned int p = 0;
2325 switch (prot) {
2326 case MEM_PROT_NONE: p = PROT_NONE; break;
2327 case MEM_PROT_READ: p = PROT_READ; break;
2328 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2329 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2330 default:
2331 ShouldNotReachHere();
2332 }
2333 // is_committed is unused.
2334 return bsd_mprotect(addr, bytes, p);
2335 }
2336
2337 bool os::guard_memory(char* addr, size_t size) {
2338 return bsd_mprotect(addr, size, PROT_NONE);
2339 }
2340
2341 bool os::unguard_memory(char* addr, size_t size) {
2342 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2343 }
2344
2345 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2346 return false;
2347 }
2348
2349 // Large page support
2350
2351 static size_t _large_page_size = 0;
2352
2353 void os::large_page_init() {
2354 }
2355
2356
2357 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2358 fatal("This code is not used or maintained.");
2359
2360 // "exec" is passed in but not used. Creating the shared image for
2361 // the code cache doesn't have an SHM_X executable permission to check.
2362 assert(UseLargePages && UseSHM, "only for SHM large pages");
2363
2364 key_t key = IPC_PRIVATE;
2365 char *addr;
2366
2367 bool warn_on_failure = UseLargePages &&
2368 (!FLAG_IS_DEFAULT(UseLargePages) ||
2369 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2370
2371 // Create a large shared memory region to attach to based on size.
2372 // Currently, size is the total size of the heap
2373 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2374 if (shmid == -1) {
2375 // Possible reasons for shmget failure:
2376 // 1. shmmax is too small for Java heap.
2377 // > check shmmax value: cat /proc/sys/kernel/shmmax
2378 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2379 // 2. not enough large page memory.
2380 // > check available large pages: cat /proc/meminfo
2381 // > increase amount of large pages:
2382 // echo new_value > /proc/sys/vm/nr_hugepages
2383 // Note 1: different Bsd may use different name for this property,
2384 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2385 // Note 2: it's possible there's enough physical memory available but
2386 // they are so fragmented after a long run that they can't
2387 // coalesce into large pages. Try to reserve large pages when
2388 // the system is still "fresh".
2389 if (warn_on_failure) {
2390 warning("Failed to reserve shared memory (errno = %d).", errno);
2391 }
2392 return NULL;
2393 }
2394
2395 // attach to the region
2396 addr = (char*)shmat(shmid, req_addr, 0);
2397 int err = errno;
2398
2399 // Remove shmid. If shmat() is successful, the actual shared memory segment
2400 // will be deleted when it's detached by shmdt() or when the process
2401 // terminates. If shmat() is not successful this will remove the shared
2402 // segment immediately.
2403 shmctl(shmid, IPC_RMID, NULL);
2404
2405 if ((intptr_t)addr == -1) {
2406 if (warn_on_failure) {
2407 warning("Failed to attach shared memory (errno = %d).", err);
2408 }
2409 return NULL;
2410 }
2411
2412 // The memory is committed
2413 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2414
2415 return addr;
2416 }
2417
2418 bool os::release_memory_special(char* base, size_t bytes) {
2419 if (MemTracker::tracking_level() > NMT_minimal) {
2420 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2421 // detaching the SHM segment will also delete it, see reserve_memory_special()
2422 int rslt = shmdt(base);
2423 if (rslt == 0) {
2424 tkr.record((address)base, bytes);
2425 return true;
2426 } else {
2427 return false;
2428 }
2429 } else {
2430 return shmdt(base) == 0;
2431 }
2432 }
2433
2434 size_t os::large_page_size() {
2435 return _large_page_size;
2436 }
2437
2438 // HugeTLBFS allows application to commit large page memory on demand;
2439 // with SysV SHM the entire memory region must be allocated as shared
2440 // memory.
2441 bool os::can_commit_large_page_memory() {
2442 return UseHugeTLBFS;
2443 }
2444
2445 bool os::can_execute_large_page_memory() {
2446 return UseHugeTLBFS;
2447 }
2448
2449 // Reserve memory at an arbitrary address, only if that area is
2450 // available (and not reserved for something else).
2451
2452 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2453 const int max_tries = 10;
2454 char* base[max_tries];
2455 size_t size[max_tries];
2456 const size_t gap = 0x000000;
2457
2458 // Assert only that the size is a multiple of the page size, since
2459 // that's all that mmap requires, and since that's all we really know
2460 // about at this low abstraction level. If we need higher alignment,
2461 // we can either pass an alignment to this method or verify alignment
2462 // in one of the methods further up the call chain. See bug 5044738.
2463 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2464
2465 // Repeatedly allocate blocks until the block is allocated at the
2466 // right spot.
2467
2468 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2469 // if kernel honors the hint then we can return immediately.
2470 char * addr = anon_mmap(requested_addr, bytes, false);
2471 if (addr == requested_addr) {
2472 return requested_addr;
2473 }
2474
2475 if (addr != NULL) {
2476 // mmap() is successful but it fails to reserve at the requested address
2477 anon_munmap(addr, bytes);
2478 }
2479
2480 int i;
2481 for (i = 0; i < max_tries; ++i) {
2482 base[i] = reserve_memory(bytes);
2483
2484 if (base[i] != NULL) {
2485 // Is this the block we wanted?
2486 if (base[i] == requested_addr) {
2487 size[i] = bytes;
2488 break;
2489 }
2490
2491 // Does this overlap the block we wanted? Give back the overlapped
2492 // parts and try again.
2493
2494 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2495 if (top_overlap >= 0 && top_overlap < bytes) {
2496 unmap_memory(base[i], top_overlap);
2497 base[i] += top_overlap;
2498 size[i] = bytes - top_overlap;
2499 } else {
2500 size_t bottom_overlap = base[i] + bytes - requested_addr;
2501 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2502 unmap_memory(requested_addr, bottom_overlap);
2503 size[i] = bytes - bottom_overlap;
2504 } else {
2505 size[i] = bytes;
2506 }
2507 }
2508 }
2509 }
2510
2511 // Give back the unused reserved pieces.
2512
2513 for (int j = 0; j < i; ++j) {
2514 if (base[j] != NULL) {
2515 unmap_memory(base[j], size[j]);
2516 }
2517 }
2518
2519 if (i < max_tries) {
2520 return requested_addr;
2521 } else {
2522 return NULL;
2523 }
2524 }
2525
2526 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2527 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2528 }
2529
2530 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2531 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2532 }
2533
2534 void os::naked_short_sleep(jlong ms) {
2535 struct timespec req;
2536
2537 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2538 req.tv_sec = 0;
2539 if (ms > 0) {
2540 req.tv_nsec = (ms % 1000) * 1000000;
2541 } else {
2542 req.tv_nsec = 1;
2543 }
2544
2545 nanosleep(&req, NULL);
2546
2547 return;
2548 }
2549
2550 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2551 void os::infinite_sleep() {
2552 while (true) { // sleep forever ...
2553 ::sleep(100); // ... 100 seconds at a time
2554 }
2555 }
2556
2557 // Used to convert frequent JVM_Yield() to nops
2558 bool os::dont_yield() {
2559 return DontYieldALot;
2560 }
2561
2562 void os::naked_yield() {
2563 sched_yield();
2564 }
2565
2566 ////////////////////////////////////////////////////////////////////////////////
2567 // thread priority support
2568
2569 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2570 // only supports dynamic priority, static priority must be zero. For real-time
2571 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2572 // However, for large multi-threaded applications, SCHED_RR is not only slower
2573 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2574 // of 5 runs - Sep 2005).
2575 //
2576 // The following code actually changes the niceness of kernel-thread/LWP. It
2577 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2578 // not the entire user process, and user level threads are 1:1 mapped to kernel
2579 // threads. It has always been the case, but could change in the future. For
2580 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2581 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2582
2583 #if !defined(__APPLE__)
2584 int os::java_to_os_priority[CriticalPriority + 1] = {
2585 19, // 0 Entry should never be used
2586
2587 0, // 1 MinPriority
2588 3, // 2
2589 6, // 3
2590
2591 10, // 4
2592 15, // 5 NormPriority
2593 18, // 6
2594
2595 21, // 7
2596 25, // 8
2597 28, // 9 NearMaxPriority
2598
2599 31, // 10 MaxPriority
2600
2601 31 // 11 CriticalPriority
2602 };
2603 #else
2604 // Using Mach high-level priority assignments
2605 int os::java_to_os_priority[CriticalPriority + 1] = {
2606 0, // 0 Entry should never be used (MINPRI_USER)
2607
2608 27, // 1 MinPriority
2609 28, // 2
2610 29, // 3
2611
2612 30, // 4
2613 31, // 5 NormPriority (BASEPRI_DEFAULT)
2614 32, // 6
2615
2616 33, // 7
2617 34, // 8
2618 35, // 9 NearMaxPriority
2619
2620 36, // 10 MaxPriority
2621
2622 36 // 11 CriticalPriority
2623 };
2624 #endif
2625
2626 static int prio_init() {
2627 if (ThreadPriorityPolicy == 1) {
2628 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2629 // if effective uid is not root. Perhaps, a more elegant way of doing
2630 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2631 if (geteuid() != 0) {
2632 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2633 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2634 }
2635 ThreadPriorityPolicy = 0;
2636 }
2637 }
2638 if (UseCriticalJavaThreadPriority) {
2639 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2640 }
2641 return 0;
2642 }
2643
2644 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2645 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2646
2647 #ifdef __OpenBSD__
2648 // OpenBSD pthread_setprio starves low priority threads
2649 return OS_OK;
2650 #elif defined(__FreeBSD__)
2651 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2652 #elif defined(__APPLE__) || defined(__NetBSD__)
2653 struct sched_param sp;
2654 int policy;
2655 pthread_t self = pthread_self();
2656
2657 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2658 return OS_ERR;
2659 }
2660
2661 sp.sched_priority = newpri;
2662 if (pthread_setschedparam(self, policy, &sp) != 0) {
2663 return OS_ERR;
2664 }
2665
2666 return OS_OK;
2667 #else
2668 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2669 return (ret == 0) ? OS_OK : OS_ERR;
2670 #endif
2671 }
2672
2673 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2674 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2675 *priority_ptr = java_to_os_priority[NormPriority];
2676 return OS_OK;
2677 }
2678
2679 errno = 0;
2680 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2681 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2682 #elif defined(__APPLE__) || defined(__NetBSD__)
2683 int policy;
2684 struct sched_param sp;
2685
2686 pthread_getschedparam(pthread_self(), &policy, &sp);
2687 *priority_ptr = sp.sched_priority;
2688 #else
2689 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2690 #endif
2691 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2692 }
2693
2694 // Hint to the underlying OS that a task switch would not be good.
2695 // Void return because it's a hint and can fail.
2696 void os::hint_no_preempt() {}
2697
2698 ////////////////////////////////////////////////////////////////////////////////
2699 // suspend/resume support
2700
2701 // the low-level signal-based suspend/resume support is a remnant from the
2702 // old VM-suspension that used to be for java-suspension, safepoints etc,
2703 // within hotspot. Now there is a single use-case for this:
2704 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2705 // that runs in the watcher thread.
2706 // The remaining code is greatly simplified from the more general suspension
2707 // code that used to be used.
2708 //
2709 // The protocol is quite simple:
2710 // - suspend:
2711 // - sends a signal to the target thread
2712 // - polls the suspend state of the osthread using a yield loop
2713 // - target thread signal handler (SR_handler) sets suspend state
2714 // and blocks in sigsuspend until continued
2715 // - resume:
2716 // - sets target osthread state to continue
2717 // - sends signal to end the sigsuspend loop in the SR_handler
2718 //
2719 // Note that the SR_lock plays no role in this suspend/resume protocol,
2720 // but is checked for NULL in SR_handler as a thread termination indicator.
2721
2722 static void resume_clear_context(OSThread *osthread) {
2723 osthread->set_ucontext(NULL);
2724 osthread->set_siginfo(NULL);
2725 }
2726
2727 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2728 osthread->set_ucontext(context);
2729 osthread->set_siginfo(siginfo);
2730 }
2731
2732 // Handler function invoked when a thread's execution is suspended or
2733 // resumed. We have to be careful that only async-safe functions are
2734 // called here (Note: most pthread functions are not async safe and
2735 // should be avoided.)
2736 //
2737 // Note: sigwait() is a more natural fit than sigsuspend() from an
2738 // interface point of view, but sigwait() prevents the signal hander
2739 // from being run. libpthread would get very confused by not having
2740 // its signal handlers run and prevents sigwait()'s use with the
2741 // mutex granting granting signal.
2742 //
2743 // Currently only ever called on the VMThread or JavaThread
2744 //
2745 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2746 // Save and restore errno to avoid confusing native code with EINTR
2747 // after sigsuspend.
2748 int old_errno = errno;
2749
2750 Thread* thread = Thread::current_or_null_safe();
2751 assert(thread != NULL, "Missing current thread in SR_handler");
2752
2753 // On some systems we have seen signal delivery get "stuck" until the signal
2754 // mask is changed as part of thread termination. Check that the current thread
2755 // has not already terminated (via SR_lock()) - else the following assertion
2756 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2757 // destructor has completed.
2758
2759 if (thread->SR_lock() == NULL) {
2760 return;
2761 }
2762
2763 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2764
2765 OSThread* osthread = thread->osthread();
2766
2767 os::SuspendResume::State current = osthread->sr.state();
2768 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2769 suspend_save_context(osthread, siginfo, context);
2770
2771 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2772 os::SuspendResume::State state = osthread->sr.suspended();
2773 if (state == os::SuspendResume::SR_SUSPENDED) {
2774 sigset_t suspend_set; // signals for sigsuspend()
2775
2776 // get current set of blocked signals and unblock resume signal
2777 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2778 sigdelset(&suspend_set, SR_signum);
2779
2780 sr_semaphore.signal();
2781 // wait here until we are resumed
2782 while (1) {
2783 sigsuspend(&suspend_set);
2784
2785 os::SuspendResume::State result = osthread->sr.running();
2786 if (result == os::SuspendResume::SR_RUNNING) {
2787 sr_semaphore.signal();
2788 break;
2789 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2790 ShouldNotReachHere();
2791 }
2792 }
2793
2794 } else if (state == os::SuspendResume::SR_RUNNING) {
2795 // request was cancelled, continue
2796 } else {
2797 ShouldNotReachHere();
2798 }
2799
2800 resume_clear_context(osthread);
2801 } else if (current == os::SuspendResume::SR_RUNNING) {
2802 // request was cancelled, continue
2803 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2804 // ignore
2805 } else {
2806 // ignore
2807 }
2808
2809 errno = old_errno;
2810 }
2811
2812
2813 static int SR_initialize() {
2814 struct sigaction act;
2815 char *s;
2816 // Get signal number to use for suspend/resume
2817 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2818 int sig = ::strtol(s, 0, 10);
2819 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2820 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2821 SR_signum = sig;
2822 } else {
2823 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2824 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2825 }
2826 }
2827
2828 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2829 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2830
2831 sigemptyset(&SR_sigset);
2832 sigaddset(&SR_sigset, SR_signum);
2833
2834 // Set up signal handler for suspend/resume
2835 act.sa_flags = SA_RESTART|SA_SIGINFO;
2836 act.sa_handler = (void (*)(int)) SR_handler;
2837
2838 // SR_signum is blocked by default.
2839 // 4528190 - We also need to block pthread restart signal (32 on all
2840 // supported Bsd platforms). Note that BsdThreads need to block
2841 // this signal for all threads to work properly. So we don't have
2842 // to use hard-coded signal number when setting up the mask.
2843 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2844
2845 if (sigaction(SR_signum, &act, 0) == -1) {
2846 return -1;
2847 }
2848
2849 // Save signal flag
2850 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2851 return 0;
2852 }
2853
2854 static int sr_notify(OSThread* osthread) {
2855 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2856 assert_status(status == 0, status, "pthread_kill");
2857 return status;
2858 }
2859
2860 // "Randomly" selected value for how long we want to spin
2861 // before bailing out on suspending a thread, also how often
2862 // we send a signal to a thread we want to resume
2863 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2864 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2865
2866 // returns true on success and false on error - really an error is fatal
2867 // but this seems the normal response to library errors
2868 static bool do_suspend(OSThread* osthread) {
2869 assert(osthread->sr.is_running(), "thread should be running");
2870 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2871
2872 // mark as suspended and send signal
2873 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2874 // failed to switch, state wasn't running?
2875 ShouldNotReachHere();
2876 return false;
2877 }
2878
2879 if (sr_notify(osthread) != 0) {
2880 ShouldNotReachHere();
2881 }
2882
2883 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2884 while (true) {
2885 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2886 break;
2887 } else {
2888 // timeout
2889 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2890 if (cancelled == os::SuspendResume::SR_RUNNING) {
2891 return false;
2892 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2893 // make sure that we consume the signal on the semaphore as well
2894 sr_semaphore.wait();
2895 break;
2896 } else {
2897 ShouldNotReachHere();
2898 return false;
2899 }
2900 }
2901 }
2902
2903 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2904 return true;
2905 }
2906
2907 static void do_resume(OSThread* osthread) {
2908 assert(osthread->sr.is_suspended(), "thread should be suspended");
2909 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2910
2911 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2912 // failed to switch to WAKEUP_REQUEST
2913 ShouldNotReachHere();
2914 return;
2915 }
2916
2917 while (true) {
2918 if (sr_notify(osthread) == 0) {
2919 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2920 if (osthread->sr.is_running()) {
2921 return;
2922 }
2923 }
2924 } else {
2925 ShouldNotReachHere();
2926 }
2927 }
2928
2929 guarantee(osthread->sr.is_running(), "Must be running!");
2930 }
2931
2932 ///////////////////////////////////////////////////////////////////////////////////
2933 // signal handling (except suspend/resume)
2934
2935 // This routine may be used by user applications as a "hook" to catch signals.
2936 // The user-defined signal handler must pass unrecognized signals to this
2937 // routine, and if it returns true (non-zero), then the signal handler must
2938 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2939 // routine will never retun false (zero), but instead will execute a VM panic
2940 // routine kill the process.
2941 //
2942 // If this routine returns false, it is OK to call it again. This allows
2943 // the user-defined signal handler to perform checks either before or after
2944 // the VM performs its own checks. Naturally, the user code would be making
2945 // a serious error if it tried to handle an exception (such as a null check
2946 // or breakpoint) that the VM was generating for its own correct operation.
2947 //
2948 // This routine may recognize any of the following kinds of signals:
2949 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2950 // It should be consulted by handlers for any of those signals.
2951 //
2952 // The caller of this routine must pass in the three arguments supplied
2953 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2954 // field of the structure passed to sigaction(). This routine assumes that
2955 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2956 //
2957 // Note that the VM will print warnings if it detects conflicting signal
2958 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2959 //
2960 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2961 void* ucontext,
2962 int abort_if_unrecognized);
2963
2964 void signalHandler(int sig, siginfo_t* info, void* uc) {
2965 assert(info != NULL && uc != NULL, "it must be old kernel");
2966 int orig_errno = errno; // Preserve errno value over signal handler.
2967 JVM_handle_bsd_signal(sig, info, uc, true);
2968 errno = orig_errno;
2969 }
2970
2971
2972 // This boolean allows users to forward their own non-matching signals
2973 // to JVM_handle_bsd_signal, harmlessly.
2974 bool os::Bsd::signal_handlers_are_installed = false;
2975
2976 // For signal-chaining
2977 struct sigaction sigact[NSIG];
2978 uint32_t sigs = 0;
2979 #if (32 < NSIG-1)
2980 #error "Not all signals can be encoded in sigs. Adapt its type!"
2981 #endif
2982 bool os::Bsd::libjsig_is_loaded = false;
2983 typedef struct sigaction *(*get_signal_t)(int);
2984 get_signal_t os::Bsd::get_signal_action = NULL;
2985
2986 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2987 struct sigaction *actp = NULL;
2988
2989 if (libjsig_is_loaded) {
2990 // Retrieve the old signal handler from libjsig
2991 actp = (*get_signal_action)(sig);
2992 }
2993 if (actp == NULL) {
2994 // Retrieve the preinstalled signal handler from jvm
2995 actp = get_preinstalled_handler(sig);
2996 }
2997
2998 return actp;
2999 }
3000
3001 static bool call_chained_handler(struct sigaction *actp, int sig,
3002 siginfo_t *siginfo, void *context) {
3003 // Call the old signal handler
3004 if (actp->sa_handler == SIG_DFL) {
3005 // It's more reasonable to let jvm treat it as an unexpected exception
3006 // instead of taking the default action.
3007 return false;
3008 } else if (actp->sa_handler != SIG_IGN) {
3009 if ((actp->sa_flags & SA_NODEFER) == 0) {
3010 // automaticlly block the signal
3011 sigaddset(&(actp->sa_mask), sig);
3012 }
3013
3014 sa_handler_t hand;
3015 sa_sigaction_t sa;
3016 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3017 // retrieve the chained handler
3018 if (siginfo_flag_set) {
3019 sa = actp->sa_sigaction;
3020 } else {
3021 hand = actp->sa_handler;
3022 }
3023
3024 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3025 actp->sa_handler = SIG_DFL;
3026 }
3027
3028 // try to honor the signal mask
3029 sigset_t oset;
3030 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3031
3032 // call into the chained handler
3033 if (siginfo_flag_set) {
3034 (*sa)(sig, siginfo, context);
3035 } else {
3036 (*hand)(sig);
3037 }
3038
3039 // restore the signal mask
3040 pthread_sigmask(SIG_SETMASK, &oset, 0);
3041 }
3042 // Tell jvm's signal handler the signal is taken care of.
3043 return true;
3044 }
3045
3046 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3047 bool chained = false;
3048 // signal-chaining
3049 if (UseSignalChaining) {
3050 struct sigaction *actp = get_chained_signal_action(sig);
3051 if (actp != NULL) {
3052 chained = call_chained_handler(actp, sig, siginfo, context);
3053 }
3054 }
3055 return chained;
3056 }
3057
3058 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3059 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
3060 return &sigact[sig];
3061 }
3062 return NULL;
3063 }
3064
3065 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3066 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3067 sigact[sig] = oldAct;
3068 sigs |= (uint32_t)1 << (sig-1);
3069 }
3070
3071 // for diagnostic
3072 int sigflags[NSIG];
3073
3074 int os::Bsd::get_our_sigflags(int sig) {
3075 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3076 return sigflags[sig];
3077 }
3078
3079 void os::Bsd::set_our_sigflags(int sig, int flags) {
3080 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3081 if (sig > 0 && sig < NSIG) {
3082 sigflags[sig] = flags;
3083 }
3084 }
3085
3086 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3087 // Check for overwrite.
3088 struct sigaction oldAct;
3089 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3090
3091 void* oldhand = oldAct.sa_sigaction
3092 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3093 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3094 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3095 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3096 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3097 if (AllowUserSignalHandlers || !set_installed) {
3098 // Do not overwrite; user takes responsibility to forward to us.
3099 return;
3100 } else if (UseSignalChaining) {
3101 // save the old handler in jvm
3102 save_preinstalled_handler(sig, oldAct);
3103 // libjsig also interposes the sigaction() call below and saves the
3104 // old sigaction on it own.
3105 } else {
3106 fatal("Encountered unexpected pre-existing sigaction handler "
3107 "%#lx for signal %d.", (long)oldhand, sig);
3108 }
3109 }
3110
3111 struct sigaction sigAct;
3112 sigfillset(&(sigAct.sa_mask));
3113 sigAct.sa_handler = SIG_DFL;
3114 if (!set_installed) {
3115 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3116 } else {
3117 sigAct.sa_sigaction = signalHandler;
3118 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3119 }
3120 #ifdef __APPLE__
3121 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3122 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3123 // if the signal handler declares it will handle it on alternate stack.
3124 // Notice we only declare we will handle it on alt stack, but we are not
3125 // actually going to use real alt stack - this is just a workaround.
3126 // Please see ux_exception.c, method catch_mach_exception_raise for details
3127 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3128 if (sig == SIGSEGV) {
3129 sigAct.sa_flags |= SA_ONSTACK;
3130 }
3131 #endif
3132
3133 // Save flags, which are set by ours
3134 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
3135 sigflags[sig] = sigAct.sa_flags;
3136
3137 int ret = sigaction(sig, &sigAct, &oldAct);
3138 assert(ret == 0, "check");
3139
3140 void* oldhand2 = oldAct.sa_sigaction
3141 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3142 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3143 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3144 }
3145
3146 // install signal handlers for signals that HotSpot needs to
3147 // handle in order to support Java-level exception handling.
3148
3149 void os::Bsd::install_signal_handlers() {
3150 if (!signal_handlers_are_installed) {
3151 signal_handlers_are_installed = true;
3152
3153 // signal-chaining
3154 typedef void (*signal_setting_t)();
3155 signal_setting_t begin_signal_setting = NULL;
3156 signal_setting_t end_signal_setting = NULL;
3157 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3158 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3159 if (begin_signal_setting != NULL) {
3160 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3161 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3162 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3163 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3164 libjsig_is_loaded = true;
3165 assert(UseSignalChaining, "should enable signal-chaining");
3166 }
3167 if (libjsig_is_loaded) {
3168 // Tell libjsig jvm is setting signal handlers
3169 (*begin_signal_setting)();
3170 }
3171
3172 set_signal_handler(SIGSEGV, true);
3173 set_signal_handler(SIGPIPE, true);
3174 set_signal_handler(SIGBUS, true);
3175 set_signal_handler(SIGILL, true);
3176 set_signal_handler(SIGFPE, true);
3177 set_signal_handler(SIGXFSZ, true);
3178
3179 #if defined(__APPLE__)
3180 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3181 // signals caught and handled by the JVM. To work around this, we reset the mach task
3182 // signal handler that's placed on our process by CrashReporter. This disables
3183 // CrashReporter-based reporting.
3184 //
3185 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3186 // on caught fatal signals.
3187 //
3188 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3189 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3190 // exception handling, while leaving the standard BSD signal handlers functional.
3191 kern_return_t kr;
3192 kr = task_set_exception_ports(mach_task_self(),
3193 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3194 MACH_PORT_NULL,
3195 EXCEPTION_STATE_IDENTITY,
3196 MACHINE_THREAD_STATE);
3197
3198 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3199 #endif
3200
3201 if (libjsig_is_loaded) {
3202 // Tell libjsig jvm finishes setting signal handlers
3203 (*end_signal_setting)();
3204 }
3205
3206 // We don't activate signal checker if libjsig is in place, we trust ourselves
3207 // and if UserSignalHandler is installed all bets are off
3208 if (CheckJNICalls) {
3209 if (libjsig_is_loaded) {
3210 if (PrintJNIResolving) {
3211 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3212 }
3213 check_signals = false;
3214 }
3215 if (AllowUserSignalHandlers) {
3216 if (PrintJNIResolving) {
3217 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3218 }
3219 check_signals = false;
3220 }
3221 }
3222 }
3223 }
3224
3225
3226 /////
3227 // glibc on Bsd platform uses non-documented flag
3228 // to indicate, that some special sort of signal
3229 // trampoline is used.
3230 // We will never set this flag, and we should
3231 // ignore this flag in our diagnostic
3232 #ifdef SIGNIFICANT_SIGNAL_MASK
3233 #undef SIGNIFICANT_SIGNAL_MASK
3234 #endif
3235 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3236
3237 static const char* get_signal_handler_name(address handler,
3238 char* buf, int buflen) {
3239 int offset;
3240 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3241 if (found) {
3242 // skip directory names
3243 const char *p1, *p2;
3244 p1 = buf;
3245 size_t len = strlen(os::file_separator());
3246 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3247 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3248 } else {
3249 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3250 }
3251 return buf;
3252 }
3253
3254 static void print_signal_handler(outputStream* st, int sig,
3255 char* buf, size_t buflen) {
3256 struct sigaction sa;
3257
3258 sigaction(sig, NULL, &sa);
3259
3260 // See comment for SIGNIFICANT_SIGNAL_MASK define
3261 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3262
3263 st->print("%s: ", os::exception_name(sig, buf, buflen));
3264
3265 address handler = (sa.sa_flags & SA_SIGINFO)
3266 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3267 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3268
3269 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3270 st->print("SIG_DFL");
3271 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3272 st->print("SIG_IGN");
3273 } else {
3274 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3275 }
3276
3277 st->print(", sa_mask[0]=");
3278 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3279
3280 address rh = VMError::get_resetted_sighandler(sig);
3281 // May be, handler was resetted by VMError?
3282 if (rh != NULL) {
3283 handler = rh;
3284 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3285 }
3286
3287 st->print(", sa_flags=");
3288 os::Posix::print_sa_flags(st, sa.sa_flags);
3289
3290 // Check: is it our handler?
3291 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3292 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3293 // It is our signal handler
3294 // check for flags, reset system-used one!
3295 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3296 st->print(
3297 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3298 os::Bsd::get_our_sigflags(sig));
3299 }
3300 }
3301 st->cr();
3302 }
3303
3304
3305 #define DO_SIGNAL_CHECK(sig) \
3306 do { \
3307 if (!sigismember(&check_signal_done, sig)) { \
3308 os::Bsd::check_signal_handler(sig); \
3309 } \
3310 } while (0)
3311
3312 // This method is a periodic task to check for misbehaving JNI applications
3313 // under CheckJNI, we can add any periodic checks here
3314
3315 void os::run_periodic_checks() {
3316
3317 if (check_signals == false) return;
3318
3319 // SEGV and BUS if overridden could potentially prevent
3320 // generation of hs*.log in the event of a crash, debugging
3321 // such a case can be very challenging, so we absolutely
3322 // check the following for a good measure:
3323 DO_SIGNAL_CHECK(SIGSEGV);
3324 DO_SIGNAL_CHECK(SIGILL);
3325 DO_SIGNAL_CHECK(SIGFPE);
3326 DO_SIGNAL_CHECK(SIGBUS);
3327 DO_SIGNAL_CHECK(SIGPIPE);
3328 DO_SIGNAL_CHECK(SIGXFSZ);
3329
3330
3331 // ReduceSignalUsage allows the user to override these handlers
3332 // see comments at the very top and jvm_solaris.h
3333 if (!ReduceSignalUsage) {
3334 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3335 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3336 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3337 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3338 }
3339
3340 DO_SIGNAL_CHECK(SR_signum);
3341 }
3342
3343 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3344
3345 static os_sigaction_t os_sigaction = NULL;
3346
3347 void os::Bsd::check_signal_handler(int sig) {
3348 char buf[O_BUFLEN];
3349 address jvmHandler = NULL;
3350
3351
3352 struct sigaction act;
3353 if (os_sigaction == NULL) {
3354 // only trust the default sigaction, in case it has been interposed
3355 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3356 if (os_sigaction == NULL) return;
3357 }
3358
3359 os_sigaction(sig, (struct sigaction*)NULL, &act);
3360
3361
3362 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3363
3364 address thisHandler = (act.sa_flags & SA_SIGINFO)
3365 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3366 : CAST_FROM_FN_PTR(address, act.sa_handler);
3367
3368
3369 switch (sig) {
3370 case SIGSEGV:
3371 case SIGBUS:
3372 case SIGFPE:
3373 case SIGPIPE:
3374 case SIGILL:
3375 case SIGXFSZ:
3376 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3377 break;
3378
3379 case SHUTDOWN1_SIGNAL:
3380 case SHUTDOWN2_SIGNAL:
3381 case SHUTDOWN3_SIGNAL:
3382 case BREAK_SIGNAL:
3383 jvmHandler = (address)user_handler();
3384 break;
3385
3386 default:
3387 if (sig == SR_signum) {
3388 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3389 } else {
3390 return;
3391 }
3392 break;
3393 }
3394
3395 if (thisHandler != jvmHandler) {
3396 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3397 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3398 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3399 // No need to check this sig any longer
3400 sigaddset(&check_signal_done, sig);
3401 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3402 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3403 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3404 exception_name(sig, buf, O_BUFLEN));
3405 }
3406 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3407 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3408 tty->print("expected:");
3409 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3410 tty->cr();
3411 tty->print(" found:");
3412 os::Posix::print_sa_flags(tty, act.sa_flags);
3413 tty->cr();
3414 // No need to check this sig any longer
3415 sigaddset(&check_signal_done, sig);
3416 }
3417
3418 // Dump all the signal
3419 if (sigismember(&check_signal_done, sig)) {
3420 print_signal_handlers(tty, buf, O_BUFLEN);
3421 }
3422 }
3423
3424 extern void report_error(char* file_name, int line_no, char* title,
3425 char* format, ...);
3426
3427 // this is called _before_ the most of global arguments have been parsed
3428 void os::init(void) {
3429 char dummy; // used to get a guess on initial stack address
3430 // first_hrtime = gethrtime();
3431
3432 // With BsdThreads the JavaMain thread pid (primordial thread)
3433 // is different than the pid of the java launcher thread.
3434 // So, on Bsd, the launcher thread pid is passed to the VM
3435 // via the sun.java.launcher.pid property.
3436 // Use this property instead of getpid() if it was correctly passed.
3437 // See bug 6351349.
3438 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3439
3440 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3441
3442 clock_tics_per_sec = CLK_TCK;
3443
3444 init_random(1234567);
3445
3446 ThreadCritical::initialize();
3447
3448 Bsd::set_page_size(getpagesize());
3449 if (Bsd::page_size() == -1) {
3450 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3451 }
3452 init_page_sizes((size_t) Bsd::page_size());
3453
3454 Bsd::initialize_system_info();
3455
3456 // main_thread points to the aboriginal thread
3457 Bsd::_main_thread = pthread_self();
3458
3459 Bsd::clock_init();
3460 initial_time_count = javaTimeNanos();
3461
3462 #ifdef __APPLE__
3463 // XXXDARWIN
3464 // Work around the unaligned VM callbacks in hotspot's
3465 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3466 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3467 // alignment when doing symbol lookup. To work around this, we force early
3468 // binding of all symbols now, thus binding when alignment is known-good.
3469 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3470 #endif
3471 }
3472
3473 // To install functions for atexit system call
3474 extern "C" {
3475 static void perfMemory_exit_helper() {
3476 perfMemory_exit();
3477 }
3478 }
3479
3480 // this is called _after_ the global arguments have been parsed
3481 jint os::init_2(void) {
3482 // Allocate a single page and mark it as readable for safepoint polling
3483 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3484 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3485
3486 os::set_polling_page(polling_page);
3487 log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3488
3489 if (!UseMembar) {
3490 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3491 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3492 os::set_memory_serialize_page(mem_serialize_page);
3493 log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3494 }
3495
3496 // initialize suspend/resume support - must do this before signal_sets_init()
3497 if (SR_initialize() != 0) {
3498 perror("SR_initialize failed");
3499 return JNI_ERR;
3500 }
3501
3502 Bsd::signal_sets_init();
3503 Bsd::install_signal_handlers();
3504
3505 // Check minimum allowable stack size for thread creation and to initialize
3506 // the java system classes, including StackOverflowError - depends on page
3507 // size. Add two 4K pages for compiler2 recursion in main thread.
3508 // Add in 4*BytesPerWord 4K pages to account for VM stack during
3509 // class initialization depending on 32 or 64 bit VM.
3510 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3511 JavaThread::stack_guard_zone_size() +
3512 JavaThread::stack_shadow_zone_size() +
3513 (4*BytesPerWord COMPILER2_PRESENT(+2)) * 4 * K);
3514
3515 os::Bsd::min_stack_allowed = align_size_up(os::Bsd::min_stack_allowed, os::vm_page_size());
3516
3517 size_t threadStackSizeInBytes = ThreadStackSize * K;
3518 if (threadStackSizeInBytes != 0 &&
3519 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3520 tty->print_cr("\nThe stack size specified is too small, "
3521 "Specify at least %dk",
3522 os::Bsd::min_stack_allowed/ K);
3523 return JNI_ERR;
3524 }
3525
3526 // Make the stack size a multiple of the page size so that
3527 // the yellow/red zones can be guarded.
3528 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3529 vm_page_size()));
3530
3531 if (MaxFDLimit) {
3532 // set the number of file descriptors to max. print out error
3533 // if getrlimit/setrlimit fails but continue regardless.
3534 struct rlimit nbr_files;
3535 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3536 if (status != 0) {
3537 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3538 } else {
3539 nbr_files.rlim_cur = nbr_files.rlim_max;
3540
3541 #ifdef __APPLE__
3542 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3543 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3544 // be used instead
3545 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3546 #endif
3547
3548 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3549 if (status != 0) {
3550 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3551 }
3552 }
3553 }
3554
3555 // at-exit methods are called in the reverse order of their registration.
3556 // atexit functions are called on return from main or as a result of a
3557 // call to exit(3C). There can be only 32 of these functions registered
3558 // and atexit() does not set errno.
3559
3560 if (PerfAllowAtExitRegistration) {
3561 // only register atexit functions if PerfAllowAtExitRegistration is set.
3562 // atexit functions can be delayed until process exit time, which
3563 // can be problematic for embedded VM situations. Embedded VMs should
3564 // call DestroyJavaVM() to assure that VM resources are released.
3565
3566 // note: perfMemory_exit_helper atexit function may be removed in
3567 // the future if the appropriate cleanup code can be added to the
3568 // VM_Exit VMOperation's doit method.
3569 if (atexit(perfMemory_exit_helper) != 0) {
3570 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3571 }
3572 }
3573
3574 // initialize thread priority policy
3575 prio_init();
3576
3577 #ifdef __APPLE__
3578 // dynamically link to objective c gc registration
3579 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3580 if (handleLibObjc != NULL) {
3581 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3582 }
3583 #endif
3584
3585 return JNI_OK;
3586 }
3587
3588 // Mark the polling page as unreadable
3589 void os::make_polling_page_unreadable(void) {
3590 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3591 fatal("Could not disable polling page");
3592 }
3593 }
3594
3595 // Mark the polling page as readable
3596 void os::make_polling_page_readable(void) {
3597 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3598 fatal("Could not enable polling page");
3599 }
3600 }
3601
3602 int os::active_processor_count() {
3603 return _processor_count;
3604 }
3605
3606 void os::set_native_thread_name(const char *name) {
3607 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3608 // This is only supported in Snow Leopard and beyond
3609 if (name != NULL) {
3610 // Add a "Java: " prefix to the name
3611 char buf[MAXTHREADNAMESIZE];
3612 snprintf(buf, sizeof(buf), "Java: %s", name);
3613 pthread_setname_np(buf);
3614 }
3615 #endif
3616 }
3617
3618 bool os::distribute_processes(uint length, uint* distribution) {
3619 // Not yet implemented.
3620 return false;
3621 }
3622
3623 bool os::bind_to_processor(uint processor_id) {
3624 // Not yet implemented.
3625 return false;
3626 }
3627
3628 void os::SuspendedThreadTask::internal_do_task() {
3629 if (do_suspend(_thread->osthread())) {
3630 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3631 do_task(context);
3632 do_resume(_thread->osthread());
3633 }
3634 }
3635
3636 ///
3637 class PcFetcher : public os::SuspendedThreadTask {
3638 public:
3639 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3640 ExtendedPC result();
3641 protected:
3642 void do_task(const os::SuspendedThreadTaskContext& context);
3643 private:
3644 ExtendedPC _epc;
3645 };
3646
3647 ExtendedPC PcFetcher::result() {
3648 guarantee(is_done(), "task is not done yet.");
3649 return _epc;
3650 }
3651
3652 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3653 Thread* thread = context.thread();
3654 OSThread* osthread = thread->osthread();
3655 if (osthread->ucontext() != NULL) {
3656 _epc = os::Bsd::ucontext_get_pc((const ucontext_t *) context.ucontext());
3657 } else {
3658 // NULL context is unexpected, double-check this is the VMThread
3659 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3660 }
3661 }
3662
3663 // Suspends the target using the signal mechanism and then grabs the PC before
3664 // resuming the target. Used by the flat-profiler only
3665 ExtendedPC os::get_thread_pc(Thread* thread) {
3666 // Make sure that it is called by the watcher for the VMThread
3667 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3668 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3669
3670 PcFetcher fetcher(thread);
3671 fetcher.run();
3672 return fetcher.result();
3673 }
3674
3675 ////////////////////////////////////////////////////////////////////////////////
3676 // debug support
3677
3678 bool os::find(address addr, outputStream* st) {
3679 Dl_info dlinfo;
3680 memset(&dlinfo, 0, sizeof(dlinfo));
3681 if (dladdr(addr, &dlinfo) != 0) {
3682 st->print(PTR_FORMAT ": ", addr);
3683 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3684 st->print("%s+%#x", dlinfo.dli_sname,
3685 addr - (intptr_t)dlinfo.dli_saddr);
3686 } else if (dlinfo.dli_fbase != NULL) {
3687 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3688 } else {
3689 st->print("<absolute address>");
3690 }
3691 if (dlinfo.dli_fname != NULL) {
3692 st->print(" in %s", dlinfo.dli_fname);
3693 }
3694 if (dlinfo.dli_fbase != NULL) {
3695 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3696 }
3697 st->cr();
3698
3699 if (Verbose) {
3700 // decode some bytes around the PC
3701 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3702 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3703 address lowest = (address) dlinfo.dli_sname;
3704 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3705 if (begin < lowest) begin = lowest;
3706 Dl_info dlinfo2;
3707 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3708 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3709 end = (address) dlinfo2.dli_saddr;
3710 }
3711 Disassembler::decode(begin, end, st);
3712 }
3713 return true;
3714 }
3715 return false;
3716 }
3717
3718 ////////////////////////////////////////////////////////////////////////////////
3719 // misc
3720
3721 // This does not do anything on Bsd. This is basically a hook for being
3722 // able to use structured exception handling (thread-local exception filters)
3723 // on, e.g., Win32.
3724 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3725 const methodHandle& method, JavaCallArguments* args,
3726 Thread* thread) {
3727 f(value, method, args, thread);
3728 }
3729
3730 void os::print_statistics() {
3731 }
3732
3733 bool os::message_box(const char* title, const char* message) {
3734 int i;
3735 fdStream err(defaultStream::error_fd());
3736 for (i = 0; i < 78; i++) err.print_raw("=");
3737 err.cr();
3738 err.print_raw_cr(title);
3739 for (i = 0; i < 78; i++) err.print_raw("-");
3740 err.cr();
3741 err.print_raw_cr(message);
3742 for (i = 0; i < 78; i++) err.print_raw("=");
3743 err.cr();
3744
3745 char buf[16];
3746 // Prevent process from exiting upon "read error" without consuming all CPU
3747 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3748
3749 return buf[0] == 'y' || buf[0] == 'Y';
3750 }
3751
3752 int os::stat(const char *path, struct stat *sbuf) {
3753 char pathbuf[MAX_PATH];
3754 if (strlen(path) > MAX_PATH - 1) {
3755 errno = ENAMETOOLONG;
3756 return -1;
3757 }
3758 os::native_path(strcpy(pathbuf, path));
3759 return ::stat(pathbuf, sbuf);
3760 }
3761
3762 static inline struct timespec get_mtime(const char* filename) {
3763 struct stat st;
3764 int ret = os::stat(filename, &st);
3765 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
3766 #ifdef __APPLE__
3767 return st.st_mtimespec;
3768 #else
3769 return st.st_mtim;
3770 #endif
3771 }
3772
3773 int os::compare_file_modified_times(const char* file1, const char* file2) {
3774 struct timespec filetime1 = get_mtime(file1);
3775 struct timespec filetime2 = get_mtime(file2);
3776 int diff = filetime1.tv_sec - filetime2.tv_sec;
3777 if (diff == 0) {
3778 return filetime1.tv_nsec - filetime2.tv_nsec;
3779 }
3780 return diff;
3781 }
3782
3783 // Is a (classpath) directory empty?
3784 bool os::dir_is_empty(const char* path) {
3785 DIR *dir = NULL;
3786 struct dirent *ptr;
3787
3788 dir = opendir(path);
3789 if (dir == NULL) return true;
3790
3791 // Scan the directory
3792 bool result = true;
3793 char buf[sizeof(struct dirent) + MAX_PATH];
3794 while (result && (ptr = ::readdir(dir)) != NULL) {
3795 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3796 result = false;
3797 }
3798 }
3799 closedir(dir);
3800 return result;
3801 }
3802
3803 // This code originates from JDK's sysOpen and open64_w
3804 // from src/solaris/hpi/src/system_md.c
3805
3806 int os::open(const char *path, int oflag, int mode) {
3807 if (strlen(path) > MAX_PATH - 1) {
3808 errno = ENAMETOOLONG;
3809 return -1;
3810 }
3811 int fd;
3812
3813 fd = ::open(path, oflag, mode);
3814 if (fd == -1) return -1;
3815
3816 // If the open succeeded, the file might still be a directory
3817 {
3818 struct stat buf;
3819 int ret = ::fstat(fd, &buf);
3820 int st_mode = buf.st_mode;
3821
3822 if (ret != -1) {
3823 if ((st_mode & S_IFMT) == S_IFDIR) {
3824 errno = EISDIR;
3825 ::close(fd);
3826 return -1;
3827 }
3828 } else {
3829 ::close(fd);
3830 return -1;
3831 }
3832 }
3833
3834 // All file descriptors that are opened in the JVM and not
3835 // specifically destined for a subprocess should have the
3836 // close-on-exec flag set. If we don't set it, then careless 3rd
3837 // party native code might fork and exec without closing all
3838 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3839 // UNIXProcess.c), and this in turn might:
3840 //
3841 // - cause end-of-file to fail to be detected on some file
3842 // descriptors, resulting in mysterious hangs, or
3843 //
3844 // - might cause an fopen in the subprocess to fail on a system
3845 // suffering from bug 1085341.
3846 //
3847 // (Yes, the default setting of the close-on-exec flag is a Unix
3848 // design flaw)
3849 //
3850 // See:
3851 // 1085341: 32-bit stdio routines should support file descriptors >255
3852 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3853 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3854 //
3855 #ifdef FD_CLOEXEC
3856 {
3857 int flags = ::fcntl(fd, F_GETFD);
3858 if (flags != -1) {
3859 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3860 }
3861 }
3862 #endif
3863
3864 return fd;
3865 }
3866
3867
3868 // create binary file, rewriting existing file if required
3869 int os::create_binary_file(const char* path, bool rewrite_existing) {
3870 int oflags = O_WRONLY | O_CREAT;
3871 if (!rewrite_existing) {
3872 oflags |= O_EXCL;
3873 }
3874 return ::open(path, oflags, S_IREAD | S_IWRITE);
3875 }
3876
3877 // return current position of file pointer
3878 jlong os::current_file_offset(int fd) {
3879 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3880 }
3881
3882 // move file pointer to the specified offset
3883 jlong os::seek_to_file_offset(int fd, jlong offset) {
3884 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3885 }
3886
3887 // This code originates from JDK's sysAvailable
3888 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3889
3890 int os::available(int fd, jlong *bytes) {
3891 jlong cur, end;
3892 int mode;
3893 struct stat buf;
3894
3895 if (::fstat(fd, &buf) >= 0) {
3896 mode = buf.st_mode;
3897 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3898 int n;
3899 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3900 *bytes = n;
3901 return 1;
3902 }
3903 }
3904 }
3905 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3906 return 0;
3907 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3908 return 0;
3909 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3910 return 0;
3911 }
3912 *bytes = end - cur;
3913 return 1;
3914 }
3915
3916 // Map a block of memory.
3917 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3918 char *addr, size_t bytes, bool read_only,
3919 bool allow_exec) {
3920 int prot;
3921 int flags;
3922
3923 if (read_only) {
3924 prot = PROT_READ;
3925 flags = MAP_SHARED;
3926 } else {
3927 prot = PROT_READ | PROT_WRITE;
3928 flags = MAP_PRIVATE;
3929 }
3930
3931 if (allow_exec) {
3932 prot |= PROT_EXEC;
3933 }
3934
3935 if (addr != NULL) {
3936 flags |= MAP_FIXED;
3937 }
3938
3939 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3940 fd, file_offset);
3941 if (mapped_address == MAP_FAILED) {
3942 return NULL;
3943 }
3944 return mapped_address;
3945 }
3946
3947
3948 // Remap a block of memory.
3949 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3950 char *addr, size_t bytes, bool read_only,
3951 bool allow_exec) {
3952 // same as map_memory() on this OS
3953 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3954 allow_exec);
3955 }
3956
3957
3958 // Unmap a block of memory.
3959 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3960 return munmap(addr, bytes) == 0;
3961 }
3962
3963 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3964 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3965 // of a thread.
3966 //
3967 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3968 // the fast estimate available on the platform.
3969
3970 jlong os::current_thread_cpu_time() {
3971 #ifdef __APPLE__
3972 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3973 #else
3974 Unimplemented();
3975 return 0;
3976 #endif
3977 }
3978
3979 jlong os::thread_cpu_time(Thread* thread) {
3980 #ifdef __APPLE__
3981 return os::thread_cpu_time(thread, true /* user + sys */);
3982 #else
3983 Unimplemented();
3984 return 0;
3985 #endif
3986 }
3987
3988 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3989 #ifdef __APPLE__
3990 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3991 #else
3992 Unimplemented();
3993 return 0;
3994 #endif
3995 }
3996
3997 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3998 #ifdef __APPLE__
3999 struct thread_basic_info tinfo;
4000 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4001 kern_return_t kr;
4002 thread_t mach_thread;
4003
4004 mach_thread = thread->osthread()->thread_id();
4005 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4006 if (kr != KERN_SUCCESS) {
4007 return -1;
4008 }
4009
4010 if (user_sys_cpu_time) {
4011 jlong nanos;
4012 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4013 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4014 return nanos;
4015 } else {
4016 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4017 }
4018 #else
4019 Unimplemented();
4020 return 0;
4021 #endif
4022 }
4023
4024
4025 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4026 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4027 info_ptr->may_skip_backward = false; // elapsed time not wall time
4028 info_ptr->may_skip_forward = false; // elapsed time not wall time
4029 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4030 }
4031
4032 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4033 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4034 info_ptr->may_skip_backward = false; // elapsed time not wall time
4035 info_ptr->may_skip_forward = false; // elapsed time not wall time
4036 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4037 }
4038
4039 bool os::is_thread_cpu_time_supported() {
4040 #ifdef __APPLE__
4041 return true;
4042 #else
4043 return false;
4044 #endif
4045 }
4046
4047 // System loadavg support. Returns -1 if load average cannot be obtained.
4048 // Bsd doesn't yet have a (official) notion of processor sets,
4049 // so just return the system wide load average.
4050 int os::loadavg(double loadavg[], int nelem) {
4051 return ::getloadavg(loadavg, nelem);
4052 }
4053
4054 void os::pause() {
4055 char filename[MAX_PATH];
4056 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4057 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4058 } else {
4059 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4060 }
4061
4062 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4063 if (fd != -1) {
4064 struct stat buf;
4065 ::close(fd);
4066 while (::stat(filename, &buf) == 0) {
4067 (void)::poll(NULL, 0, 100);
4068 }
4069 } else {
4070 jio_fprintf(stderr,
4071 "Could not open pause file '%s', continuing immediately.\n", filename);
4072 }
4073 }
4074
4075
4076 // Refer to the comments in os_solaris.cpp park-unpark. The next two
4077 // comment paragraphs are worth repeating here:
4078 //
4079 // Assumption:
4080 // Only one parker can exist on an event, which is why we allocate
4081 // them per-thread. Multiple unparkers can coexist.
4082 //
4083 // _Event serves as a restricted-range semaphore.
4084 // -1 : thread is blocked, i.e. there is a waiter
4085 // 0 : neutral: thread is running or ready,
4086 // could have been signaled after a wait started
4087 // 1 : signaled - thread is running or ready
4088 //
4089
4090 // utility to compute the abstime argument to timedwait:
4091 // millis is the relative timeout time
4092 // abstime will be the absolute timeout time
4093 // TODO: replace compute_abstime() with unpackTime()
4094
4095 static struct timespec* compute_abstime(struct timespec* abstime,
4096 jlong millis) {
4097 if (millis < 0) millis = 0;
4098 struct timeval now;
4099 int status = gettimeofday(&now, NULL);
4100 assert(status == 0, "gettimeofday");
4101 jlong seconds = millis / 1000;
4102 millis %= 1000;
4103 if (seconds > 50000000) { // see man cond_timedwait(3T)
4104 seconds = 50000000;
4105 }
4106 abstime->tv_sec = now.tv_sec + seconds;
4107 long usec = now.tv_usec + millis * 1000;
4108 if (usec >= 1000000) {
4109 abstime->tv_sec += 1;
4110 usec -= 1000000;
4111 }
4112 abstime->tv_nsec = usec * 1000;
4113 return abstime;
4114 }
4115
4116 void os::PlatformEvent::park() { // AKA "down()"
4117 // Transitions for _Event:
4118 // -1 => -1 : illegal
4119 // 1 => 0 : pass - return immediately
4120 // 0 => -1 : block; then set _Event to 0 before returning
4121
4122 // Invariant: Only the thread associated with the Event/PlatformEvent
4123 // may call park().
4124 // TODO: assert that _Assoc != NULL or _Assoc == Self
4125 assert(_nParked == 0, "invariant");
4126
4127 int v;
4128 for (;;) {
4129 v = _Event;
4130 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4131 }
4132 guarantee(v >= 0, "invariant");
4133 if (v == 0) {
4134 // Do this the hard way by blocking ...
4135 int status = pthread_mutex_lock(_mutex);
4136 assert_status(status == 0, status, "mutex_lock");
4137 guarantee(_nParked == 0, "invariant");
4138 ++_nParked;
4139 while (_Event < 0) {
4140 status = pthread_cond_wait(_cond, _mutex);
4141 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4142 // Treat this the same as if the wait was interrupted
4143 if (status == ETIMEDOUT) { status = EINTR; }
4144 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4145 }
4146 --_nParked;
4147
4148 _Event = 0;
4149 status = pthread_mutex_unlock(_mutex);
4150 assert_status(status == 0, status, "mutex_unlock");
4151 // Paranoia to ensure our locked and lock-free paths interact
4152 // correctly with each other.
4153 OrderAccess::fence();
4154 }
4155 guarantee(_Event >= 0, "invariant");
4156 }
4157
4158 int os::PlatformEvent::park(jlong millis) {
4159 // Transitions for _Event:
4160 // -1 => -1 : illegal
4161 // 1 => 0 : pass - return immediately
4162 // 0 => -1 : block; then set _Event to 0 before returning
4163
4164 guarantee(_nParked == 0, "invariant");
4165
4166 int v;
4167 for (;;) {
4168 v = _Event;
4169 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4170 }
4171 guarantee(v >= 0, "invariant");
4172 if (v != 0) return OS_OK;
4173
4174 // We do this the hard way, by blocking the thread.
4175 // Consider enforcing a minimum timeout value.
4176 struct timespec abst;
4177 compute_abstime(&abst, millis);
4178
4179 int ret = OS_TIMEOUT;
4180 int status = pthread_mutex_lock(_mutex);
4181 assert_status(status == 0, status, "mutex_lock");
4182 guarantee(_nParked == 0, "invariant");
4183 ++_nParked;
4184
4185 // Object.wait(timo) will return because of
4186 // (a) notification
4187 // (b) timeout
4188 // (c) thread.interrupt
4189 //
4190 // Thread.interrupt and object.notify{All} both call Event::set.
4191 // That is, we treat thread.interrupt as a special case of notification.
4192 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4193 // We assume all ETIME returns are valid.
4194 //
4195 // TODO: properly differentiate simultaneous notify+interrupt.
4196 // In that case, we should propagate the notify to another waiter.
4197
4198 while (_Event < 0) {
4199 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4200 assert_status(status == 0 || status == EINTR ||
4201 status == ETIMEDOUT,
4202 status, "cond_timedwait");
4203 if (!FilterSpuriousWakeups) break; // previous semantics
4204 if (status == ETIMEDOUT) break;
4205 // We consume and ignore EINTR and spurious wakeups.
4206 }
4207 --_nParked;
4208 if (_Event >= 0) {
4209 ret = OS_OK;
4210 }
4211 _Event = 0;
4212 status = pthread_mutex_unlock(_mutex);
4213 assert_status(status == 0, status, "mutex_unlock");
4214 assert(_nParked == 0, "invariant");
4215 // Paranoia to ensure our locked and lock-free paths interact
4216 // correctly with each other.
4217 OrderAccess::fence();
4218 return ret;
4219 }
4220
4221 void os::PlatformEvent::unpark() {
4222 // Transitions for _Event:
4223 // 0 => 1 : just return
4224 // 1 => 1 : just return
4225 // -1 => either 0 or 1; must signal target thread
4226 // That is, we can safely transition _Event from -1 to either
4227 // 0 or 1.
4228 // See also: "Semaphores in Plan 9" by Mullender & Cox
4229 //
4230 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4231 // that it will take two back-to-back park() calls for the owning
4232 // thread to block. This has the benefit of forcing a spurious return
4233 // from the first park() call after an unpark() call which will help
4234 // shake out uses of park() and unpark() without condition variables.
4235
4236 if (Atomic::xchg(1, &_Event) >= 0) return;
4237
4238 // Wait for the thread associated with the event to vacate
4239 int status = pthread_mutex_lock(_mutex);
4240 assert_status(status == 0, status, "mutex_lock");
4241 int AnyWaiters = _nParked;
4242 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4243 status = pthread_mutex_unlock(_mutex);
4244 assert_status(status == 0, status, "mutex_unlock");
4245 if (AnyWaiters != 0) {
4246 // Note that we signal() *after* dropping the lock for "immortal" Events.
4247 // This is safe and avoids a common class of futile wakeups. In rare
4248 // circumstances this can cause a thread to return prematurely from
4249 // cond_{timed}wait() but the spurious wakeup is benign and the victim
4250 // will simply re-test the condition and re-park itself.
4251 // This provides particular benefit if the underlying platform does not
4252 // provide wait morphing.
4253 status = pthread_cond_signal(_cond);
4254 assert_status(status == 0, status, "cond_signal");
4255 }
4256 }
4257
4258
4259 // JSR166
4260 // -------------------------------------------------------
4261
4262 // The solaris and bsd implementations of park/unpark are fairly
4263 // conservative for now, but can be improved. They currently use a
4264 // mutex/condvar pair, plus a a count.
4265 // Park decrements count if > 0, else does a condvar wait. Unpark
4266 // sets count to 1 and signals condvar. Only one thread ever waits
4267 // on the condvar. Contention seen when trying to park implies that someone
4268 // is unparking you, so don't wait. And spurious returns are fine, so there
4269 // is no need to track notifications.
4270
4271 #define MAX_SECS 100000000
4272
4273 // This code is common to bsd and solaris and will be moved to a
4274 // common place in dolphin.
4275 //
4276 // The passed in time value is either a relative time in nanoseconds
4277 // or an absolute time in milliseconds. Either way it has to be unpacked
4278 // into suitable seconds and nanoseconds components and stored in the
4279 // given timespec structure.
4280 // Given time is a 64-bit value and the time_t used in the timespec is only
4281 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4282 // overflow if times way in the future are given. Further on Solaris versions
4283 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4284 // number of seconds, in abstime, is less than current_time + 100,000,000.
4285 // As it will be 28 years before "now + 100000000" will overflow we can
4286 // ignore overflow and just impose a hard-limit on seconds using the value
4287 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4288 // years from "now".
4289
4290 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4291 assert(time > 0, "convertTime");
4292
4293 struct timeval now;
4294 int status = gettimeofday(&now, NULL);
4295 assert(status == 0, "gettimeofday");
4296
4297 time_t max_secs = now.tv_sec + MAX_SECS;
4298
4299 if (isAbsolute) {
4300 jlong secs = time / 1000;
4301 if (secs > max_secs) {
4302 absTime->tv_sec = max_secs;
4303 } else {
4304 absTime->tv_sec = secs;
4305 }
4306 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4307 } else {
4308 jlong secs = time / NANOSECS_PER_SEC;
4309 if (secs >= MAX_SECS) {
4310 absTime->tv_sec = max_secs;
4311 absTime->tv_nsec = 0;
4312 } else {
4313 absTime->tv_sec = now.tv_sec + secs;
4314 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4315 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4316 absTime->tv_nsec -= NANOSECS_PER_SEC;
4317 ++absTime->tv_sec; // note: this must be <= max_secs
4318 }
4319 }
4320 }
4321 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4322 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4323 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4324 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4325 }
4326
4327 void Parker::park(bool isAbsolute, jlong time) {
4328 // Ideally we'd do something useful while spinning, such
4329 // as calling unpackTime().
4330
4331 // Optional fast-path check:
4332 // Return immediately if a permit is available.
4333 // We depend on Atomic::xchg() having full barrier semantics
4334 // since we are doing a lock-free update to _counter.
4335 if (Atomic::xchg(0, &_counter) > 0) return;
4336
4337 Thread* thread = Thread::current();
4338 assert(thread->is_Java_thread(), "Must be JavaThread");
4339 JavaThread *jt = (JavaThread *)thread;
4340
4341 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4342 // Check interrupt before trying to wait
4343 if (Thread::is_interrupted(thread, false)) {
4344 return;
4345 }
4346
4347 // Next, demultiplex/decode time arguments
4348 struct timespec absTime;
4349 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4350 return;
4351 }
4352 if (time > 0) {
4353 unpackTime(&absTime, isAbsolute, time);
4354 }
4355
4356
4357 // Enter safepoint region
4358 // Beware of deadlocks such as 6317397.
4359 // The per-thread Parker:: mutex is a classic leaf-lock.
4360 // In particular a thread must never block on the Threads_lock while
4361 // holding the Parker:: mutex. If safepoints are pending both the
4362 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4363 ThreadBlockInVM tbivm(jt);
4364
4365 // Don't wait if cannot get lock since interference arises from
4366 // unblocking. Also. check interrupt before trying wait
4367 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4368 return;
4369 }
4370
4371 int status;
4372 if (_counter > 0) { // no wait needed
4373 _counter = 0;
4374 status = pthread_mutex_unlock(_mutex);
4375 assert_status(status == 0, status, "invariant");
4376 // Paranoia to ensure our locked and lock-free paths interact
4377 // correctly with each other and Java-level accesses.
4378 OrderAccess::fence();
4379 return;
4380 }
4381
4382 #ifdef ASSERT
4383 // Don't catch signals while blocked; let the running threads have the signals.
4384 // (This allows a debugger to break into the running thread.)
4385 sigset_t oldsigs;
4386 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4387 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4388 #endif
4389
4390 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4391 jt->set_suspend_equivalent();
4392 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4393
4394 if (time == 0) {
4395 status = pthread_cond_wait(_cond, _mutex);
4396 } else {
4397 status = pthread_cond_timedwait(_cond, _mutex, &absTime);
4398 }
4399 assert_status(status == 0 || status == EINTR ||
4400 status == ETIMEDOUT,
4401 status, "cond_timedwait");
4402
4403 #ifdef ASSERT
4404 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4405 #endif
4406
4407 _counter = 0;
4408 status = pthread_mutex_unlock(_mutex);
4409 assert_status(status == 0, status, "invariant");
4410 // Paranoia to ensure our locked and lock-free paths interact
4411 // correctly with each other and Java-level accesses.
4412 OrderAccess::fence();
4413
4414 // If externally suspended while waiting, re-suspend
4415 if (jt->handle_special_suspend_equivalent_condition()) {
4416 jt->java_suspend_self();
4417 }
4418 }
4419
4420 void Parker::unpark() {
4421 int status = pthread_mutex_lock(_mutex);
4422 assert_status(status == 0, status, "invariant");
4423 const int s = _counter;
4424 _counter = 1;
4425 status = pthread_mutex_unlock(_mutex);
4426 assert_status(status == 0, status, "invariant");
4427 if (s < 1) {
4428 status = pthread_cond_signal(_cond);
4429 assert_status(status == 0, status, "invariant");
4430 }
4431 }
4432
4433
4434 // Darwin has no "environ" in a dynamic library.
4435 #ifdef __APPLE__
4436 #include <crt_externs.h>
4437 #define environ (*_NSGetEnviron())
4438 #else
4439 extern char** environ;
4440 #endif
4441
4442 // Run the specified command in a separate process. Return its exit value,
4443 // or -1 on failure (e.g. can't fork a new process).
4444 // Unlike system(), this function can be called from signal handler. It
4445 // doesn't block SIGINT et al.
4446 int os::fork_and_exec(char* cmd) {
4447 const char * argv[4] = {"sh", "-c", cmd, NULL};
4448
4449 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4450 // pthread_atfork handlers and reset pthread library. All we need is a
4451 // separate process to execve. Make a direct syscall to fork process.
4452 // On IA64 there's no fork syscall, we have to use fork() and hope for
4453 // the best...
4454 pid_t pid = fork();
4455
4456 if (pid < 0) {
4457 // fork failed
4458 return -1;
4459
4460 } else if (pid == 0) {
4461 // child process
4462
4463 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4464 // first to kill every thread on the thread list. Because this list is
4465 // not reset by fork() (see notes above), execve() will instead kill
4466 // every thread in the parent process. We know this is the only thread
4467 // in the new process, so make a system call directly.
4468 // IA64 should use normal execve() from glibc to match the glibc fork()
4469 // above.
4470 execve("/bin/sh", (char* const*)argv, environ);
4471
4472 // execve failed
4473 _exit(-1);
4474
4475 } else {
4476 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4477 // care about the actual exit code, for now.
4478
4479 int status;
4480
4481 // Wait for the child process to exit. This returns immediately if
4482 // the child has already exited. */
4483 while (waitpid(pid, &status, 0) < 0) {
4484 switch (errno) {
4485 case ECHILD: return 0;
4486 case EINTR: break;
4487 default: return -1;
4488 }
4489 }
4490
4491 if (WIFEXITED(status)) {
4492 // The child exited normally; get its exit code.
4493 return WEXITSTATUS(status);
4494 } else if (WIFSIGNALED(status)) {
4495 // The child exited because of a signal
4496 // The best value to return is 0x80 + signal number,
4497 // because that is what all Unix shells do, and because
4498 // it allows callers to distinguish between process exit and
4499 // process death by signal.
4500 return 0x80 + WTERMSIG(status);
4501 } else {
4502 // Unknown exit code; pass it through
4503 return status;
4504 }
4505 }
4506 }
4507
4508 // is_headless_jre()
4509 //
4510 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4511 // in order to report if we are running in a headless jre
4512 //
4513 // Since JDK8 xawt/libmawt.so was moved into the same directory
4514 // as libawt.so, and renamed libawt_xawt.so
4515 //
4516 bool os::is_headless_jre() {
4517 #ifdef __APPLE__
4518 // We no longer build headless-only on Mac OS X
4519 return false;
4520 #else
4521 struct stat statbuf;
4522 char buf[MAXPATHLEN];
4523 char libmawtpath[MAXPATHLEN];
4524 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4525 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4526 char *p;
4527
4528 // Get path to libjvm.so
4529 os::jvm_path(buf, sizeof(buf));
4530
4531 // Get rid of libjvm.so
4532 p = strrchr(buf, '/');
4533 if (p == NULL) {
4534 return false;
4535 } else {
4536 *p = '\0';
4537 }
4538
4539 // Get rid of client or server
4540 p = strrchr(buf, '/');
4541 if (p == NULL) {
4542 return false;
4543 } else {
4544 *p = '\0';
4545 }
4546
4547 // check xawt/libmawt.so
4548 strcpy(libmawtpath, buf);
4549 strcat(libmawtpath, xawtstr);
4550 if (::stat(libmawtpath, &statbuf) == 0) return false;
4551
4552 // check libawt_xawt.so
4553 strcpy(libmawtpath, buf);
4554 strcat(libmawtpath, new_xawtstr);
4555 if (::stat(libmawtpath, &statbuf) == 0) return false;
4556
4557 return true;
4558 #endif
4559 }
4560
4561 // Get the default path to the core file
4562 // Returns the length of the string
4563 int os::get_core_path(char* buffer, size_t bufferSize) {
4564 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4565
4566 // Truncate if theoretical string was longer than bufferSize
4567 n = MIN2(n, (int)bufferSize);
4568
4569 return n;
4570 }
4571
4572 #ifndef PRODUCT
4573 void TestReserveMemorySpecial_test() {
4574 // No tests available for this platform
4575 }
4576 #endif
4577
4578 bool os::start_debugging(char *buf, int buflen) {
4579 int len = (int)strlen(buf);
4580 char *p = &buf[len];
4581
4582 jio_snprintf(p, buflen-len,
4583 "\n\n"
4584 "Do you want to debug the problem?\n\n"
4585 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
4586 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
4587 "Otherwise, press RETURN to abort...",
4588 os::current_process_id(), os::current_process_id(),
4589 os::current_thread_id(), os::current_thread_id());
4590
4591 bool yes = os::message_box("Unexpected Error", buf);
4592
4593 if (yes) {
4594 // yes, user asked VM to launch debugger
4595 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
4596 os::current_process_id(), os::current_process_id());
4597
4598 os::fork_and_exec(buf);
4599 yes = false;
4600 }
4601 return yes;
4602 }