1 /*
2 * Copyright (c) 1999, 2019, 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 "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/disassembler.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "logging/log.hpp"
36 #include "logging/logStream.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/filemap.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "os_bsd.inline.hpp"
41 #include "os_posix.inline.hpp"
42 #include "os_share_bsd.hpp"
43 #include "prims/jniFastGetField.hpp"
44 #include "prims/jvm_misc.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/atomic.hpp"
47 #include "runtime/extendedPC.hpp"
48 #include "runtime/globals.hpp"
49 #include "runtime/interfaceSupport.inline.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/objectMonitor.hpp"
54 #include "runtime/orderAccess.hpp"
55 #include "runtime/osThread.hpp"
56 #include "runtime/perfMemory.hpp"
57 #include "runtime/semaphore.hpp"
58 #include "runtime/sharedRuntime.hpp"
59 #include "runtime/statSampler.hpp"
60 #include "runtime/stubRoutines.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "runtime/threadCritical.hpp"
63 #include "runtime/timer.hpp"
64 #include "services/attachListener.hpp"
65 #include "services/memTracker.hpp"
66 #include "services/runtimeService.hpp"
67 #include "utilities/align.hpp"
68 #include "utilities/decoder.hpp"
69 #include "utilities/defaultStream.hpp"
70 #include "utilities/events.hpp"
71 #include "utilities/growableArray.hpp"
72 #include "utilities/vmError.hpp"
73
74 // put OS-includes here
75 # include <dlfcn.h>
76 # include <errno.h>
77 # include <fcntl.h>
78 # include <inttypes.h>
79 # include <poll.h>
80 # include <pthread.h>
81 # include <pwd.h>
82 # include <signal.h>
83 # include <stdint.h>
84 # include <stdio.h>
85 # include <string.h>
86 # include <sys/ioctl.h>
87 # include <sys/mman.h>
88 # include <sys/param.h>
89 # include <sys/resource.h>
90 # include <sys/socket.h>
91 # include <sys/stat.h>
92 # include <sys/syscall.h>
93 # include <sys/sysctl.h>
94 # include <sys/time.h>
95 # include <sys/times.h>
96 # include <sys/types.h>
97 # include <sys/wait.h>
98 # include <time.h>
99 # include <unistd.h>
100
101 #if defined(__FreeBSD__) || defined(__NetBSD__)
102 #include <elf.h>
103 #endif
104
105 #ifdef __APPLE__
106 #include <mach-o/dyld.h>
107 #endif
108
109 #ifndef MAP_ANONYMOUS
110 #define MAP_ANONYMOUS MAP_ANON
111 #endif
112
113 #define MAX_PATH (2 * K)
114
115 // for timer info max values which include all bits
116 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
117
118 ////////////////////////////////////////////////////////////////////////////////
119 // global variables
120 julong os::Bsd::_physical_memory = 0;
121
122 #ifdef __APPLE__
123 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
124 volatile uint64_t os::Bsd::_max_abstime = 0;
125 #else
126 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
127 #endif
128 pthread_t os::Bsd::_main_thread;
129 int os::Bsd::_page_size = -1;
130
131 static jlong initial_time_count=0;
132
133 static int clock_tics_per_sec = 100;
134
135 // For diagnostics to print a message once. see run_periodic_checks
136 static sigset_t check_signal_done;
137 static bool check_signals = true;
138
139 // Signal number used to suspend/resume a thread
140
141 // do not use any signal number less than SIGSEGV, see 4355769
142 static int SR_signum = SIGUSR2;
143 sigset_t SR_sigset;
144
145
146 ////////////////////////////////////////////////////////////////////////////////
147 // utility functions
148
149 static int SR_initialize();
150
151 julong os::available_memory() {
152 return Bsd::available_memory();
153 }
154
155 // available here means free
156 julong os::Bsd::available_memory() {
157 uint64_t available = physical_memory() >> 2;
158 #ifdef __APPLE__
159 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
160 vm_statistics64_data_t vmstat;
161 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
162 (host_info64_t)&vmstat, &count);
163 assert(kerr == KERN_SUCCESS,
164 "host_statistics64 failed - check mach_host_self() and count");
165 if (kerr == KERN_SUCCESS) {
166 available = vmstat.free_count * os::vm_page_size();
167 }
168 #endif
169 return available;
170 }
171
172 // for more info see :
173 // https://developer.apple.com/library/archive/documentation/System/Conceptual/ManPages_iPhoneOS/man3/sysctl.3.html
174 void os::Bsd::print_uptime_info(outputStream* st) {
175 struct timeval boottime;
176 size_t len = sizeof(boottime);
177 int mib[2];
178 mib[0] = CTL_KERN;
179 mib[1] = KERN_BOOTTIME;
180
181 if (sysctl(mib, 2, &boottime, &len, NULL, 0) >= 0) {
182 time_t bootsec = boottime.tv_sec, currsec = time(NULL);
183 double tdiff = difftime(currsec, bootsec);
184 st->print_cr("OS uptime (in days): %.2lf", tdiff/(60.0*60.0*24.0));
185 }
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 #ifndef OVERRIDE_LIBPATH
336 #define DEFAULT_LIBPATH "/lib:/usr/lib"
337 #else
338 #define DEFAULT_LIBPATH OVERRIDE_LIBPATH
339 #endif
340 #endif
341
342 // Base path of extensions installed on the system.
343 #define SYS_EXT_DIR "/usr/java/packages"
344 #define EXTENSIONS_DIR "/lib/ext"
345
346 #ifndef __APPLE__
347
348 // Buffer that fits several sprintfs.
349 // Note that the space for the colon and the trailing null are provided
350 // by the nulls included by the sizeof operator.
351 const size_t bufsize =
352 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
353 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
354 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
355
356 // sysclasspath, java_home, dll_dir
357 {
358 char *pslash;
359 os::jvm_path(buf, bufsize);
360
361 // Found the full path to libjvm.so.
362 // Now cut the path to <java_home>/jre if we can.
363 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
364 pslash = strrchr(buf, '/');
365 if (pslash != NULL) {
366 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
367 }
368 Arguments::set_dll_dir(buf);
369
370 if (pslash != NULL) {
371 pslash = strrchr(buf, '/');
372 if (pslash != NULL) {
373 *pslash = '\0'; // Get rid of /<arch>.
374 pslash = strrchr(buf, '/');
375 if (pslash != NULL) {
376 *pslash = '\0'; // Get rid of /lib.
377 }
378 }
379 }
380 Arguments::set_java_home(buf);
381 if (!set_boot_path('/', ':')) {
382 vm_exit_during_initialization("Failed setting boot class path.", NULL);
383 }
384 }
385
386 // Where to look for native libraries.
387 //
388 // Note: Due to a legacy implementation, most of the library path
389 // is set in the launcher. This was to accomodate linking restrictions
390 // on legacy Bsd implementations (which are no longer supported).
391 // Eventually, all the library path setting will be done here.
392 //
393 // However, to prevent the proliferation of improperly built native
394 // libraries, the new path component /usr/java/packages is added here.
395 // Eventually, all the library path setting will be done here.
396 {
397 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
398 // should always exist (until the legacy problem cited above is
399 // addressed).
400 const char *v = ::getenv("LD_LIBRARY_PATH");
401 const char *v_colon = ":";
402 if (v == NULL) { v = ""; v_colon = ""; }
403 // That's +1 for the colon and +1 for the trailing '\0'.
404 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
405 strlen(v) + 1 +
406 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
407 mtInternal);
408 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
409 Arguments::set_library_path(ld_library_path);
410 FREE_C_HEAP_ARRAY(char, ld_library_path);
411 }
412
413 // Extensions directories.
414 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
415 Arguments::set_ext_dirs(buf);
416
417 FREE_C_HEAP_ARRAY(char, buf);
418
419 #else // __APPLE__
420
421 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
422 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
423
424 const char *user_home_dir = get_home();
425 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
426 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
427 sizeof(SYS_EXTENSIONS_DIRS);
428
429 // Buffer that fits several sprintfs.
430 // Note that the space for the colon and the trailing null are provided
431 // by the nulls included by the sizeof operator.
432 const size_t bufsize =
433 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
434 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
435 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
436
437 // sysclasspath, java_home, dll_dir
438 {
439 char *pslash;
440 os::jvm_path(buf, bufsize);
441
442 // Found the full path to libjvm.so.
443 // Now cut the path to <java_home>/jre if we can.
444 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
445 pslash = strrchr(buf, '/');
446 if (pslash != NULL) {
447 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
448 }
449 #ifdef STATIC_BUILD
450 strcat(buf, "/lib");
451 #endif
452
453 Arguments::set_dll_dir(buf);
454
455 if (pslash != NULL) {
456 pslash = strrchr(buf, '/');
457 if (pslash != NULL) {
458 *pslash = '\0'; // Get rid of /lib.
459 }
460 }
461 Arguments::set_java_home(buf);
462 set_boot_path('/', ':');
463 }
464
465 // Where to look for native libraries.
466 //
467 // Note: Due to a legacy implementation, most of the library path
468 // is set in the launcher. This was to accomodate linking restrictions
469 // on legacy Bsd implementations (which are no longer supported).
470 // Eventually, all the library path setting will be done here.
471 //
472 // However, to prevent the proliferation of improperly built native
473 // libraries, the new path component /usr/java/packages is added here.
474 // Eventually, all the library path setting will be done here.
475 {
476 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
477 // should always exist (until the legacy problem cited above is
478 // addressed).
479 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
480 // can specify a directory inside an app wrapper
481 const char *l = ::getenv("JAVA_LIBRARY_PATH");
482 const char *l_colon = ":";
483 if (l == NULL) { l = ""; l_colon = ""; }
484
485 const char *v = ::getenv("DYLD_LIBRARY_PATH");
486 const char *v_colon = ":";
487 if (v == NULL) { v = ""; v_colon = ""; }
488
489 // Apple's Java6 has "." at the beginning of java.library.path.
490 // OpenJDK on Windows has "." at the end of java.library.path.
491 // OpenJDK on Linux and Solaris don't have "." in java.library.path
492 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
493 // "." is appended to the end of java.library.path. Yes, this
494 // could cause a change in behavior, but Apple's Java6 behavior
495 // can be achieved by putting "." at the beginning of the
496 // JAVA_LIBRARY_PATH environment variable.
497 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
498 strlen(v) + 1 + strlen(l) + 1 +
499 system_ext_size + 3,
500 mtInternal);
501 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
502 v, v_colon, l, l_colon, user_home_dir);
503 Arguments::set_library_path(ld_library_path);
504 FREE_C_HEAP_ARRAY(char, ld_library_path);
505 }
506
507 // Extensions directories.
508 //
509 // Note that the space for the colon and the trailing null are provided
510 // by the nulls included by the sizeof operator (so actually one byte more
511 // than necessary is allocated).
512 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
513 user_home_dir, Arguments::get_java_home());
514 Arguments::set_ext_dirs(buf);
515
516 FREE_C_HEAP_ARRAY(char, buf);
517
518 #undef SYS_EXTENSIONS_DIR
519 #undef SYS_EXTENSIONS_DIRS
520
521 #endif // __APPLE__
522
523 #undef SYS_EXT_DIR
524 #undef EXTENSIONS_DIR
525 }
526
527 ////////////////////////////////////////////////////////////////////////////////
528 // breakpoint support
529
530 void os::breakpoint() {
531 BREAKPOINT;
532 }
533
534 extern "C" void breakpoint() {
535 // use debugger to set breakpoint here
536 }
537
538 ////////////////////////////////////////////////////////////////////////////////
539 // signal support
540
541 debug_only(static bool signal_sets_initialized = false);
542 static sigset_t unblocked_sigs, vm_sigs;
543
544 void os::Bsd::signal_sets_init() {
545 // Should also have an assertion stating we are still single-threaded.
546 assert(!signal_sets_initialized, "Already initialized");
547 // Fill in signals that are necessarily unblocked for all threads in
548 // the VM. Currently, we unblock the following signals:
549 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
550 // by -Xrs (=ReduceSignalUsage));
551 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
552 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
553 // the dispositions or masks wrt these signals.
554 // Programs embedding the VM that want to use the above signals for their
555 // own purposes must, at this time, use the "-Xrs" option to prevent
556 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
557 // (See bug 4345157, and other related bugs).
558 // In reality, though, unblocking these signals is really a nop, since
559 // these signals are not blocked by default.
560 sigemptyset(&unblocked_sigs);
561 sigaddset(&unblocked_sigs, SIGILL);
562 sigaddset(&unblocked_sigs, SIGSEGV);
563 sigaddset(&unblocked_sigs, SIGBUS);
564 sigaddset(&unblocked_sigs, SIGFPE);
565 sigaddset(&unblocked_sigs, SR_signum);
566
567 if (!ReduceSignalUsage) {
568 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
569 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
570
571 }
572 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
573 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
574 }
575 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
576 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
577 }
578 }
579 // Fill in signals that are blocked by all but the VM thread.
580 sigemptyset(&vm_sigs);
581 if (!ReduceSignalUsage) {
582 sigaddset(&vm_sigs, BREAK_SIGNAL);
583 }
584 debug_only(signal_sets_initialized = true);
585
586 }
587
588 // These are signals that are unblocked while a thread is running Java.
589 // (For some reason, they get blocked by default.)
590 sigset_t* os::Bsd::unblocked_signals() {
591 assert(signal_sets_initialized, "Not initialized");
592 return &unblocked_sigs;
593 }
594
595 // These are the signals that are blocked while a (non-VM) thread is
596 // running Java. Only the VM thread handles these signals.
597 sigset_t* os::Bsd::vm_signals() {
598 assert(signal_sets_initialized, "Not initialized");
599 return &vm_sigs;
600 }
601
602 void os::Bsd::hotspot_sigmask(Thread* thread) {
603
604 //Save caller's signal mask before setting VM signal mask
605 sigset_t caller_sigmask;
606 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
607
608 OSThread* osthread = thread->osthread();
609 osthread->set_caller_sigmask(caller_sigmask);
610
611 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
612
613 if (!ReduceSignalUsage) {
614 if (thread->is_VM_thread()) {
615 // Only the VM thread handles BREAK_SIGNAL ...
616 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
617 } else {
618 // ... all other threads block BREAK_SIGNAL
619 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
620 }
621 }
622 }
623
624
625 //////////////////////////////////////////////////////////////////////////////
626 // create new thread
627
628 #ifdef __APPLE__
629 // library handle for calling objc_registerThreadWithCollector()
630 // without static linking to the libobjc library
631 #define OBJC_LIB "/usr/lib/libobjc.dylib"
632 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
633 typedef void (*objc_registerThreadWithCollector_t)();
634 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
635 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
636 #endif
637
638 #ifdef __APPLE__
639 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
640 // Additional thread_id used to correlate threads in SA
641 thread_identifier_info_data_t m_ident_info;
642 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
643
644 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
645 (thread_info_t) &m_ident_info, &count);
646
647 return m_ident_info.thread_id;
648 }
649 #endif
650
651 // Thread start routine for all newly created threads
652 static void *thread_native_entry(Thread *thread) {
653
654 thread->record_stack_base_and_size();
655
656 // Try to randomize the cache line index of hot stack frames.
657 // This helps when threads of the same stack traces evict each other's
658 // cache lines. The threads can be either from the same JVM instance, or
659 // from different JVM instances. The benefit is especially true for
660 // processors with hyperthreading technology.
661 static int counter = 0;
662 int pid = os::current_process_id();
663 alloca(((pid ^ counter++) & 7) * 128);
664
665 thread->initialize_thread_current();
666
667 OSThread* osthread = thread->osthread();
668 Monitor* sync = osthread->startThread_lock();
669
670 osthread->set_thread_id(os::Bsd::gettid());
671
672 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
673 os::current_thread_id(), (uintx) pthread_self());
674
675 #ifdef __APPLE__
676 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
677 guarantee(unique_thread_id != 0, "unique thread id was not found");
678 osthread->set_unique_thread_id(unique_thread_id);
679 #endif
680 // initialize signal mask for this thread
681 os::Bsd::hotspot_sigmask(thread);
682
683 // initialize floating point control register
684 os::Bsd::init_thread_fpu_state();
685
686 #ifdef __APPLE__
687 // register thread with objc gc
688 if (objc_registerThreadWithCollectorFunction != NULL) {
689 objc_registerThreadWithCollectorFunction();
690 }
691 #endif
692
693 // handshaking with parent thread
694 {
695 MutexLocker ml(sync, Mutex::_no_safepoint_check_flag);
696
697 // notify parent thread
698 osthread->set_state(INITIALIZED);
699 sync->notify_all();
700
701 // wait until os::start_thread()
702 while (osthread->get_state() == INITIALIZED) {
703 sync->wait_without_safepoint_check();
704 }
705 }
706
707 // call one more level start routine
708 thread->call_run();
709
710 // Note: at this point the thread object may already have deleted itself.
711 // Prevent dereferencing it from here on out.
712 thread = NULL;
713
714 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
715 os::current_thread_id(), (uintx) pthread_self());
716
717 return 0;
718 }
719
720 bool os::create_thread(Thread* thread, ThreadType thr_type,
721 size_t req_stack_size) {
722 assert(thread->osthread() == NULL, "caller responsible");
723
724 // Allocate the OSThread object
725 OSThread* osthread = new OSThread(NULL, NULL);
726 if (osthread == NULL) {
727 return false;
728 }
729
730 // set the correct thread state
731 osthread->set_thread_type(thr_type);
732
733 // Initial state is ALLOCATED but not INITIALIZED
734 osthread->set_state(ALLOCATED);
735
736 thread->set_osthread(osthread);
737
738 // init thread attributes
739 pthread_attr_t attr;
740 pthread_attr_init(&attr);
741 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
742
743 // calculate stack size if it's not specified by caller
744 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
745 int status = pthread_attr_setstacksize(&attr, stack_size);
746 assert_status(status == 0, status, "pthread_attr_setstacksize");
747
748 ThreadState state;
749
750 {
751 pthread_t tid;
752 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
753
754 char buf[64];
755 if (ret == 0) {
756 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
757 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
758 } else {
759 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
760 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
761 // Log some OS information which might explain why creating the thread failed.
762 log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
763 LogStream st(Log(os, thread)::info());
764 os::Posix::print_rlimit_info(&st);
765 os::print_memory_info(&st);
766 }
767
768 pthread_attr_destroy(&attr);
769
770 if (ret != 0) {
771 // Need to clean up stuff we've allocated so far
772 thread->set_osthread(NULL);
773 delete osthread;
774 return false;
775 }
776
777 // Store pthread info into the OSThread
778 osthread->set_pthread_id(tid);
779
780 // Wait until child thread is either initialized or aborted
781 {
782 Monitor* sync_with_child = osthread->startThread_lock();
783 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
784 while ((state = osthread->get_state()) == ALLOCATED) {
785 sync_with_child->wait_without_safepoint_check();
786 }
787 }
788
789 }
790
791 // Aborted due to thread limit being reached
792 if (state == ZOMBIE) {
793 thread->set_osthread(NULL);
794 delete osthread;
795 return false;
796 }
797
798 // The thread is returned suspended (in state INITIALIZED),
799 // and is started higher up in the call chain
800 assert(state == INITIALIZED, "race condition");
801 return true;
802 }
803
804 /////////////////////////////////////////////////////////////////////////////
805 // attach existing thread
806
807 // bootstrap the main thread
808 bool os::create_main_thread(JavaThread* thread) {
809 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
810 return create_attached_thread(thread);
811 }
812
813 bool os::create_attached_thread(JavaThread* thread) {
814 #ifdef ASSERT
815 thread->verify_not_published();
816 #endif
817
818 // Allocate the OSThread object
819 OSThread* osthread = new OSThread(NULL, NULL);
820
821 if (osthread == NULL) {
822 return false;
823 }
824
825 osthread->set_thread_id(os::Bsd::gettid());
826
827 // Store pthread info into the OSThread
828 #ifdef __APPLE__
829 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
830 guarantee(unique_thread_id != 0, "just checking");
831 osthread->set_unique_thread_id(unique_thread_id);
832 #endif
833 osthread->set_pthread_id(::pthread_self());
834
835 // initialize floating point control register
836 os::Bsd::init_thread_fpu_state();
837
838 // Initial thread state is RUNNABLE
839 osthread->set_state(RUNNABLE);
840
841 thread->set_osthread(osthread);
842
843 // initialize signal mask for this thread
844 // and save the caller's signal mask
845 os::Bsd::hotspot_sigmask(thread);
846
847 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
848 os::current_thread_id(), (uintx) pthread_self());
849
850 return true;
851 }
852
853 void os::pd_start_thread(Thread* thread) {
854 OSThread * osthread = thread->osthread();
855 assert(osthread->get_state() != INITIALIZED, "just checking");
856 Monitor* sync_with_child = osthread->startThread_lock();
857 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
858 sync_with_child->notify();
859 }
860
861 // Free Bsd resources related to the OSThread
862 void os::free_thread(OSThread* osthread) {
863 assert(osthread != NULL, "osthread not set");
864
865 // We are told to free resources of the argument thread,
866 // but we can only really operate on the current thread.
867 assert(Thread::current()->osthread() == osthread,
868 "os::free_thread but not current thread");
869
870 // Restore caller's signal mask
871 sigset_t sigmask = osthread->caller_sigmask();
872 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
873
874 delete osthread;
875 }
876
877 ////////////////////////////////////////////////////////////////////////////////
878 // time support
879
880 // Time since start-up in seconds to a fine granularity.
881 // Used by VMSelfDestructTimer and the MemProfiler.
882 double os::elapsedTime() {
883
884 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
885 }
886
887 jlong os::elapsed_counter() {
888 return javaTimeNanos() - initial_time_count;
889 }
890
891 jlong os::elapsed_frequency() {
892 return NANOSECS_PER_SEC; // nanosecond resolution
893 }
894
895 bool os::supports_vtime() { return true; }
896
897 double os::elapsedVTime() {
898 // better than nothing, but not much
899 return elapsedTime();
900 }
901
902 jlong os::javaTimeMillis() {
903 timeval time;
904 int status = gettimeofday(&time, NULL);
905 assert(status != -1, "bsd error");
906 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
907 }
908
909 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
910 timeval time;
911 int status = gettimeofday(&time, NULL);
912 assert(status != -1, "bsd error");
913 seconds = jlong(time.tv_sec);
914 nanos = jlong(time.tv_usec) * 1000;
915 }
916
917 #ifndef __APPLE__
918 #ifndef CLOCK_MONOTONIC
919 #define CLOCK_MONOTONIC (1)
920 #endif
921 #endif
922
923 #ifdef __APPLE__
924 void os::Bsd::clock_init() {
925 mach_timebase_info(&_timebase_info);
926 }
927 #else
928 void os::Bsd::clock_init() {
929 struct timespec res;
930 struct timespec tp;
931 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
932 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
933 // yes, monotonic clock is supported
934 _clock_gettime = ::clock_gettime;
935 }
936 }
937 #endif
938
939
940
941 #ifdef __APPLE__
942
943 jlong os::javaTimeNanos() {
944 const uint64_t tm = mach_absolute_time();
945 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
946 const uint64_t prev = Bsd::_max_abstime;
947 if (now <= prev) {
948 return prev; // same or retrograde time;
949 }
950 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev);
951 assert(obsv >= prev, "invariant"); // Monotonicity
952 // If the CAS succeeded then we're done and return "now".
953 // If the CAS failed and the observed value "obsv" is >= now then
954 // we should return "obsv". If the CAS failed and now > obsv > prv then
955 // some other thread raced this thread and installed a new value, in which case
956 // we could either (a) retry the entire operation, (b) retry trying to install now
957 // or (c) just return obsv. We use (c). No loop is required although in some cases
958 // we might discard a higher "now" value in deference to a slightly lower but freshly
959 // installed obsv value. That's entirely benign -- it admits no new orderings compared
960 // to (a) or (b) -- and greatly reduces coherence traffic.
961 // We might also condition (c) on the magnitude of the delta between obsv and now.
962 // Avoiding excessive CAS operations to hot RW locations is critical.
963 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
964 return (prev == obsv) ? now : obsv;
965 }
966
967 #else // __APPLE__
968
969 jlong os::javaTimeNanos() {
970 if (os::supports_monotonic_clock()) {
971 struct timespec tp;
972 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
973 assert(status == 0, "gettime error");
974 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
975 return result;
976 } else {
977 timeval time;
978 int status = gettimeofday(&time, NULL);
979 assert(status != -1, "bsd error");
980 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
981 return 1000 * usecs;
982 }
983 }
984
985 #endif // __APPLE__
986
987 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
988 if (os::supports_monotonic_clock()) {
989 info_ptr->max_value = ALL_64_BITS;
990
991 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
992 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
993 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
994 } else {
995 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
996 info_ptr->max_value = ALL_64_BITS;
997
998 // gettimeofday is a real time clock so it skips
999 info_ptr->may_skip_backward = true;
1000 info_ptr->may_skip_forward = true;
1001 }
1002
1003 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1004 }
1005
1006 // Return the real, user, and system times in seconds from an
1007 // arbitrary fixed point in the past.
1008 bool os::getTimesSecs(double* process_real_time,
1009 double* process_user_time,
1010 double* process_system_time) {
1011 struct tms ticks;
1012 clock_t real_ticks = times(&ticks);
1013
1014 if (real_ticks == (clock_t) (-1)) {
1015 return false;
1016 } else {
1017 double ticks_per_second = (double) clock_tics_per_sec;
1018 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1019 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1020 *process_real_time = ((double) real_ticks) / ticks_per_second;
1021
1022 return true;
1023 }
1024 }
1025
1026
1027 char * os::local_time_string(char *buf, size_t buflen) {
1028 struct tm t;
1029 time_t long_time;
1030 time(&long_time);
1031 localtime_r(&long_time, &t);
1032 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1033 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1034 t.tm_hour, t.tm_min, t.tm_sec);
1035 return buf;
1036 }
1037
1038 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1039 return localtime_r(clock, res);
1040 }
1041
1042 ////////////////////////////////////////////////////////////////////////////////
1043 // runtime exit support
1044
1045 // Note: os::shutdown() might be called very early during initialization, or
1046 // called from signal handler. Before adding something to os::shutdown(), make
1047 // sure it is async-safe and can handle partially initialized VM.
1048 void os::shutdown() {
1049
1050 // allow PerfMemory to attempt cleanup of any persistent resources
1051 perfMemory_exit();
1052
1053 // needs to remove object in file system
1054 AttachListener::abort();
1055
1056 // flush buffered output, finish log files
1057 ostream_abort();
1058
1059 // Check for abort hook
1060 abort_hook_t abort_hook = Arguments::abort_hook();
1061 if (abort_hook != NULL) {
1062 abort_hook();
1063 }
1064
1065 }
1066
1067 // Note: os::abort() might be called very early during initialization, or
1068 // called from signal handler. Before adding something to os::abort(), make
1069 // sure it is async-safe and can handle partially initialized VM.
1070 void os::abort(bool dump_core, void* siginfo, const void* context) {
1071 os::shutdown();
1072 if (dump_core) {
1073 #ifndef PRODUCT
1074 fdStream out(defaultStream::output_fd());
1075 out.print_raw("Current thread is ");
1076 char buf[16];
1077 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1078 out.print_raw_cr(buf);
1079 out.print_raw_cr("Dumping core ...");
1080 #endif
1081 ::abort(); // dump core
1082 }
1083
1084 ::exit(1);
1085 }
1086
1087 // Die immediately, no exit hook, no abort hook, no cleanup.
1088 // Dump a core file, if possible, for debugging.
1089 void os::die() {
1090 if (TestUnresponsiveErrorHandler && !CreateCoredumpOnCrash) {
1091 // For TimeoutInErrorHandlingTest.java, we just kill the VM
1092 // and don't take the time to generate a core file.
1093 os::signal_raise(SIGKILL);
1094 } else {
1095 // _exit() on BsdThreads only kills current thread
1096 ::abort();
1097 }
1098 }
1099
1100 // Information of current thread in variety of formats
1101 pid_t os::Bsd::gettid() {
1102 int retval = -1;
1103
1104 #ifdef __APPLE__ //XNU kernel
1105 // despite the fact mach port is actually not a thread id use it
1106 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1107 retval = ::pthread_mach_thread_np(::pthread_self());
1108 guarantee(retval != 0, "just checking");
1109 return retval;
1110
1111 #else
1112 #ifdef __FreeBSD__
1113 retval = syscall(SYS_thr_self);
1114 #else
1115 #ifdef __OpenBSD__
1116 retval = syscall(SYS_getthrid);
1117 #else
1118 #ifdef __NetBSD__
1119 retval = (pid_t) syscall(SYS__lwp_self);
1120 #endif
1121 #endif
1122 #endif
1123 #endif
1124
1125 if (retval == -1) {
1126 return getpid();
1127 }
1128 }
1129
1130 intx os::current_thread_id() {
1131 #ifdef __APPLE__
1132 return (intx)::pthread_mach_thread_np(::pthread_self());
1133 #else
1134 return (intx)::pthread_self();
1135 #endif
1136 }
1137
1138 int os::current_process_id() {
1139 return (int)(getpid());
1140 }
1141
1142 // DLL functions
1143
1144 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1145
1146 // This must be hard coded because it's the system's temporary
1147 // directory not the java application's temp directory, ala java.io.tmpdir.
1148 #ifdef __APPLE__
1149 // macosx has a secure per-user temporary directory
1150 char temp_path_storage[PATH_MAX];
1151 const char* os::get_temp_directory() {
1152 static char *temp_path = NULL;
1153 if (temp_path == NULL) {
1154 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1155 if (pathSize == 0 || pathSize > PATH_MAX) {
1156 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1157 }
1158 temp_path = temp_path_storage;
1159 }
1160 return temp_path;
1161 }
1162 #else // __APPLE__
1163 const char* os::get_temp_directory() { return "/tmp"; }
1164 #endif // __APPLE__
1165
1166 // check if addr is inside libjvm.so
1167 bool os::address_is_in_vm(address addr) {
1168 static address libjvm_base_addr;
1169 Dl_info dlinfo;
1170
1171 if (libjvm_base_addr == NULL) {
1172 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1173 libjvm_base_addr = (address)dlinfo.dli_fbase;
1174 }
1175 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1176 }
1177
1178 if (dladdr((void *)addr, &dlinfo) != 0) {
1179 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1180 }
1181
1182 return false;
1183 }
1184
1185
1186 #define MACH_MAXSYMLEN 256
1187
1188 bool os::dll_address_to_function_name(address addr, char *buf,
1189 int buflen, int *offset,
1190 bool demangle) {
1191 // buf is not optional, but offset is optional
1192 assert(buf != NULL, "sanity check");
1193
1194 Dl_info dlinfo;
1195 char localbuf[MACH_MAXSYMLEN];
1196
1197 if (dladdr((void*)addr, &dlinfo) != 0) {
1198 // see if we have a matching symbol
1199 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1200 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1201 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1202 }
1203 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1204 return true;
1205 }
1206 // no matching symbol so try for just file info
1207 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1208 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1209 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1210 return true;
1211 }
1212 }
1213
1214 // Handle non-dynamic manually:
1215 if (dlinfo.dli_fbase != NULL &&
1216 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1217 dlinfo.dli_fbase)) {
1218 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1219 jio_snprintf(buf, buflen, "%s", localbuf);
1220 }
1221 return true;
1222 }
1223 }
1224 buf[0] = '\0';
1225 if (offset != NULL) *offset = -1;
1226 return false;
1227 }
1228
1229 // ported from solaris version
1230 bool os::dll_address_to_library_name(address addr, char* buf,
1231 int buflen, int* offset) {
1232 // buf is not optional, but offset is optional
1233 assert(buf != NULL, "sanity check");
1234
1235 Dl_info dlinfo;
1236
1237 if (dladdr((void*)addr, &dlinfo) != 0) {
1238 if (dlinfo.dli_fname != NULL) {
1239 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1240 }
1241 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1242 *offset = addr - (address)dlinfo.dli_fbase;
1243 }
1244 return true;
1245 }
1246
1247 buf[0] = '\0';
1248 if (offset) *offset = -1;
1249 return false;
1250 }
1251
1252 // Loads .dll/.so and
1253 // in case of error it checks if .dll/.so was built for the
1254 // same architecture as Hotspot is running on
1255
1256 #ifdef __APPLE__
1257 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1258 #ifdef STATIC_BUILD
1259 return os::get_default_process_handle();
1260 #else
1261 log_info(os)("attempting shared library load of %s", filename);
1262
1263 void * result= ::dlopen(filename, RTLD_LAZY);
1264 if (result != NULL) {
1265 Events::log(NULL, "Loaded shared library %s", filename);
1266 // Successful loading
1267 log_info(os)("shared library load of %s was successful", filename);
1268 return result;
1269 }
1270
1271 const char* error_report = ::dlerror();
1272 if (error_report == NULL) {
1273 error_report = "dlerror returned no error description";
1274 }
1275 if (ebuf != NULL && ebuflen > 0) {
1276 // Read system error message into ebuf
1277 ::strncpy(ebuf, error_report, ebuflen-1);
1278 ebuf[ebuflen-1]='\0';
1279 }
1280 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1281 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1282
1283 return NULL;
1284 #endif // STATIC_BUILD
1285 }
1286 #else
1287 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1288 #ifdef STATIC_BUILD
1289 return os::get_default_process_handle();
1290 #else
1291 log_info(os)("attempting shared library load of %s", filename);
1292 void * result= ::dlopen(filename, RTLD_LAZY);
1293 if (result != NULL) {
1294 Events::log(NULL, "Loaded shared library %s", filename);
1295 // Successful loading
1296 log_info(os)("shared library load of %s was successful", filename);
1297 return result;
1298 }
1299
1300 Elf32_Ehdr elf_head;
1301
1302 const char* const error_report = ::dlerror();
1303 if (error_report == NULL) {
1304 error_report = "dlerror returned no error description";
1305 }
1306 if (ebuf != NULL && ebuflen > 0) {
1307 // Read system error message into ebuf
1308 ::strncpy(ebuf, error_report, ebuflen-1);
1309 ebuf[ebuflen-1]='\0';
1310 }
1311 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1312 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1313
1314 int diag_msg_max_length=ebuflen-strlen(ebuf);
1315 char* diag_msg_buf=ebuf+strlen(ebuf);
1316
1317 if (diag_msg_max_length==0) {
1318 // No more space in ebuf for additional diagnostics message
1319 return NULL;
1320 }
1321
1322
1323 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1324
1325 if (file_descriptor < 0) {
1326 // Can't open library, report dlerror() message
1327 return NULL;
1328 }
1329
1330 bool failed_to_read_elf_head=
1331 (sizeof(elf_head)!=
1332 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1333
1334 ::close(file_descriptor);
1335 if (failed_to_read_elf_head) {
1336 // file i/o error - report dlerror() msg
1337 return NULL;
1338 }
1339
1340 typedef struct {
1341 Elf32_Half code; // Actual value as defined in elf.h
1342 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1343 char elf_class; // 32 or 64 bit
1344 char endianess; // MSB or LSB
1345 char* name; // String representation
1346 } arch_t;
1347
1348 #ifndef EM_486
1349 #define EM_486 6 /* Intel 80486 */
1350 #endif
1351
1352 #ifndef EM_MIPS_RS3_LE
1353 #define EM_MIPS_RS3_LE 10 /* MIPS */
1354 #endif
1355
1356 #ifndef EM_PPC64
1357 #define EM_PPC64 21 /* PowerPC64 */
1358 #endif
1359
1360 #ifndef EM_S390
1361 #define EM_S390 22 /* IBM System/390 */
1362 #endif
1363
1364 #ifndef EM_IA_64
1365 #define EM_IA_64 50 /* HP/Intel IA-64 */
1366 #endif
1367
1368 #ifndef EM_X86_64
1369 #define EM_X86_64 62 /* AMD x86-64 */
1370 #endif
1371
1372 static const arch_t arch_array[]={
1373 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1374 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1375 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1376 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1377 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1378 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1379 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1380 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1381 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1382 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1383 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1384 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1385 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1386 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1387 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1388 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1389 };
1390
1391 #if (defined IA32)
1392 static Elf32_Half running_arch_code=EM_386;
1393 #elif (defined AMD64)
1394 static Elf32_Half running_arch_code=EM_X86_64;
1395 #elif (defined IA64)
1396 static Elf32_Half running_arch_code=EM_IA_64;
1397 #elif (defined __sparc) && (defined _LP64)
1398 static Elf32_Half running_arch_code=EM_SPARCV9;
1399 #elif (defined __sparc) && (!defined _LP64)
1400 static Elf32_Half running_arch_code=EM_SPARC;
1401 #elif (defined __powerpc64__)
1402 static Elf32_Half running_arch_code=EM_PPC64;
1403 #elif (defined __powerpc__)
1404 static Elf32_Half running_arch_code=EM_PPC;
1405 #elif (defined ARM)
1406 static Elf32_Half running_arch_code=EM_ARM;
1407 #elif (defined S390)
1408 static Elf32_Half running_arch_code=EM_S390;
1409 #elif (defined ALPHA)
1410 static Elf32_Half running_arch_code=EM_ALPHA;
1411 #elif (defined MIPSEL)
1412 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1413 #elif (defined PARISC)
1414 static Elf32_Half running_arch_code=EM_PARISC;
1415 #elif (defined MIPS)
1416 static Elf32_Half running_arch_code=EM_MIPS;
1417 #elif (defined M68K)
1418 static Elf32_Half running_arch_code=EM_68K;
1419 #else
1420 #error Method os::dll_load requires that one of following is defined:\
1421 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1422 #endif
1423
1424 // Identify compatability class for VM's architecture and library's architecture
1425 // Obtain string descriptions for architectures
1426
1427 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1428 int running_arch_index=-1;
1429
1430 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1431 if (running_arch_code == arch_array[i].code) {
1432 running_arch_index = i;
1433 }
1434 if (lib_arch.code == arch_array[i].code) {
1435 lib_arch.compat_class = arch_array[i].compat_class;
1436 lib_arch.name = arch_array[i].name;
1437 }
1438 }
1439
1440 assert(running_arch_index != -1,
1441 "Didn't find running architecture code (running_arch_code) in arch_array");
1442 if (running_arch_index == -1) {
1443 // Even though running architecture detection failed
1444 // we may still continue with reporting dlerror() message
1445 return NULL;
1446 }
1447
1448 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1449 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1450 return NULL;
1451 }
1452
1453 #ifndef S390
1454 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1455 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1456 return NULL;
1457 }
1458 #endif // !S390
1459
1460 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1461 if (lib_arch.name!=NULL) {
1462 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1463 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1464 lib_arch.name, arch_array[running_arch_index].name);
1465 } else {
1466 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1467 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1468 lib_arch.code,
1469 arch_array[running_arch_index].name);
1470 }
1471 }
1472
1473 return NULL;
1474 #endif // STATIC_BUILD
1475 }
1476 #endif // !__APPLE__
1477
1478 void* os::get_default_process_handle() {
1479 #ifdef __APPLE__
1480 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1481 // to avoid finding unexpected symbols on second (or later)
1482 // loads of a library.
1483 return (void*)::dlopen(NULL, RTLD_FIRST);
1484 #else
1485 return (void*)::dlopen(NULL, RTLD_LAZY);
1486 #endif
1487 }
1488
1489 // XXX: Do we need a lock around this as per Linux?
1490 void* os::dll_lookup(void* handle, const char* name) {
1491 return dlsym(handle, name);
1492 }
1493
1494 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1495 outputStream * out = (outputStream *) param;
1496 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1497 return 0;
1498 }
1499
1500 void os::print_dll_info(outputStream *st) {
1501 st->print_cr("Dynamic libraries:");
1502 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1503 st->print_cr("Error: Cannot print dynamic libraries.");
1504 }
1505 }
1506
1507 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1508 #ifdef RTLD_DI_LINKMAP
1509 Dl_info dli;
1510 void *handle;
1511 Link_map *map;
1512 Link_map *p;
1513
1514 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1515 dli.dli_fname == NULL) {
1516 return 1;
1517 }
1518 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1519 if (handle == NULL) {
1520 return 1;
1521 }
1522 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1523 if (map == NULL) {
1524 dlclose(handle);
1525 return 1;
1526 }
1527
1528 while (map->l_prev != NULL)
1529 map = map->l_prev;
1530
1531 while (map != NULL) {
1532 // Value for top_address is returned as 0 since we don't have any information about module size
1533 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1534 dlclose(handle);
1535 return 1;
1536 }
1537 map = map->l_next;
1538 }
1539
1540 dlclose(handle);
1541 #elif defined(__APPLE__)
1542 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1543 // Value for top_address is returned as 0 since we don't have any information about module size
1544 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1545 return 1;
1546 }
1547 }
1548 return 0;
1549 #else
1550 return 1;
1551 #endif
1552 }
1553
1554 void os::get_summary_os_info(char* buf, size_t buflen) {
1555 // These buffers are small because we want this to be brief
1556 // and not use a lot of stack while generating the hs_err file.
1557 char os[100];
1558 size_t size = sizeof(os);
1559 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1560 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1561 #ifdef __APPLE__
1562 strncpy(os, "Darwin", sizeof(os));
1563 #elif __OpenBSD__
1564 strncpy(os, "OpenBSD", sizeof(os));
1565 #else
1566 strncpy(os, "BSD", sizeof(os));
1567 #endif
1568 }
1569
1570 char release[100];
1571 size = sizeof(release);
1572 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1573 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1574 // if error, leave blank
1575 strncpy(release, "", sizeof(release));
1576 }
1577 snprintf(buf, buflen, "%s %s", os, release);
1578 }
1579
1580 void os::print_os_info_brief(outputStream* st) {
1581 os::Posix::print_uname_info(st);
1582 }
1583
1584 void os::print_os_info(outputStream* st) {
1585 st->print("OS:");
1586
1587 os::Posix::print_uname_info(st);
1588
1589 os::Bsd::print_uptime_info(st);
1590
1591 os::Posix::print_rlimit_info(st);
1592
1593 os::Posix::print_load_average(st);
1594 }
1595
1596 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1597 // Nothing to do for now.
1598 }
1599
1600 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1601 unsigned int mhz;
1602 size_t size = sizeof(mhz);
1603 int mib[] = { CTL_HW, HW_CPU_FREQ };
1604 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1605 mhz = 1; // looks like an error but can be divided by
1606 } else {
1607 mhz /= 1000000; // reported in millions
1608 }
1609
1610 char model[100];
1611 size = sizeof(model);
1612 int mib_model[] = { CTL_HW, HW_MODEL };
1613 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1614 strncpy(model, cpu_arch, sizeof(model));
1615 }
1616
1617 char machine[100];
1618 size = sizeof(machine);
1619 int mib_machine[] = { CTL_HW, HW_MACHINE };
1620 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1621 strncpy(machine, "", sizeof(machine));
1622 }
1623
1624 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1625 }
1626
1627 void os::print_memory_info(outputStream* st) {
1628 xsw_usage swap_usage;
1629 size_t size = sizeof(swap_usage);
1630
1631 st->print("Memory:");
1632 st->print(" %dk page", os::vm_page_size()>>10);
1633
1634 st->print(", physical " UINT64_FORMAT "k",
1635 os::physical_memory() >> 10);
1636 st->print("(" UINT64_FORMAT "k free)",
1637 os::available_memory() >> 10);
1638
1639 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1640 if (size >= offset_of(xsw_usage, xsu_used)) {
1641 st->print(", swap " UINT64_FORMAT "k",
1642 ((julong) swap_usage.xsu_total) >> 10);
1643 st->print("(" UINT64_FORMAT "k free)",
1644 ((julong) swap_usage.xsu_avail) >> 10);
1645 }
1646 }
1647
1648 st->cr();
1649 }
1650
1651 static void print_signal_handler(outputStream* st, int sig,
1652 char* buf, size_t buflen);
1653
1654 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1655 st->print_cr("Signal Handlers:");
1656 print_signal_handler(st, SIGSEGV, buf, buflen);
1657 print_signal_handler(st, SIGBUS , buf, buflen);
1658 print_signal_handler(st, SIGFPE , buf, buflen);
1659 print_signal_handler(st, SIGPIPE, buf, buflen);
1660 print_signal_handler(st, SIGXFSZ, buf, buflen);
1661 print_signal_handler(st, SIGILL , buf, buflen);
1662 print_signal_handler(st, SR_signum, buf, buflen);
1663 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1664 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1665 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1666 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1667 }
1668
1669 static char saved_jvm_path[MAXPATHLEN] = {0};
1670
1671 // Find the full path to the current module, libjvm
1672 void os::jvm_path(char *buf, jint buflen) {
1673 // Error checking.
1674 if (buflen < MAXPATHLEN) {
1675 assert(false, "must use a large-enough buffer");
1676 buf[0] = '\0';
1677 return;
1678 }
1679 // Lazy resolve the path to current module.
1680 if (saved_jvm_path[0] != 0) {
1681 strcpy(buf, saved_jvm_path);
1682 return;
1683 }
1684
1685 char dli_fname[MAXPATHLEN];
1686 bool ret = dll_address_to_library_name(
1687 CAST_FROM_FN_PTR(address, os::jvm_path),
1688 dli_fname, sizeof(dli_fname), NULL);
1689 assert(ret, "cannot locate libjvm");
1690 char *rp = NULL;
1691 if (ret && dli_fname[0] != '\0') {
1692 rp = os::Posix::realpath(dli_fname, buf, buflen);
1693 }
1694 if (rp == NULL) {
1695 return;
1696 }
1697
1698 if (Arguments::sun_java_launcher_is_altjvm()) {
1699 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1700 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1701 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1702 // appears at the right place in the string, then assume we are
1703 // installed in a JDK and we're done. Otherwise, check for a
1704 // JAVA_HOME environment variable and construct a path to the JVM
1705 // being overridden.
1706
1707 const char *p = buf + strlen(buf) - 1;
1708 for (int count = 0; p > buf && count < 5; ++count) {
1709 for (--p; p > buf && *p != '/'; --p)
1710 /* empty */ ;
1711 }
1712
1713 if (strncmp(p, "/jre/lib/", 9) != 0) {
1714 // Look for JAVA_HOME in the environment.
1715 char* java_home_var = ::getenv("JAVA_HOME");
1716 if (java_home_var != NULL && java_home_var[0] != 0) {
1717 char* jrelib_p;
1718 int len;
1719
1720 // Check the current module name "libjvm"
1721 p = strrchr(buf, '/');
1722 assert(strstr(p, "/libjvm") == p, "invalid library name");
1723
1724 rp = os::Posix::realpath(java_home_var, buf, buflen);
1725 if (rp == NULL) {
1726 return;
1727 }
1728
1729 // determine if this is a legacy image or modules image
1730 // modules image doesn't have "jre" subdirectory
1731 len = strlen(buf);
1732 assert(len < buflen, "Ran out of buffer space");
1733 jrelib_p = buf + len;
1734
1735 // Add the appropriate library subdir
1736 snprintf(jrelib_p, buflen-len, "/jre/lib");
1737 if (0 != access(buf, F_OK)) {
1738 snprintf(jrelib_p, buflen-len, "/lib");
1739 }
1740
1741 // Add the appropriate client or server subdir
1742 len = strlen(buf);
1743 jrelib_p = buf + len;
1744 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1745 if (0 != access(buf, F_OK)) {
1746 snprintf(jrelib_p, buflen-len, "%s", "");
1747 }
1748
1749 // If the path exists within JAVA_HOME, add the JVM library name
1750 // to complete the path to JVM being overridden. Otherwise fallback
1751 // to the path to the current library.
1752 if (0 == access(buf, F_OK)) {
1753 // Use current module name "libjvm"
1754 len = strlen(buf);
1755 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1756 } else {
1757 // Fall back to path of current library
1758 rp = os::Posix::realpath(dli_fname, buf, buflen);
1759 if (rp == NULL) {
1760 return;
1761 }
1762 }
1763 }
1764 }
1765 }
1766
1767 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1768 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1769 }
1770
1771 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1772 // no prefix required, not even "_"
1773 }
1774
1775 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1776 // no suffix required
1777 }
1778
1779 ////////////////////////////////////////////////////////////////////////////////
1780 // sun.misc.Signal support
1781
1782 static void UserHandler(int sig, void *siginfo, void *context) {
1783 // Ctrl-C is pressed during error reporting, likely because the error
1784 // handler fails to abort. Let VM die immediately.
1785 if (sig == SIGINT && VMError::is_error_reported()) {
1786 os::die();
1787 }
1788
1789 os::signal_notify(sig);
1790 }
1791
1792 void* os::user_handler() {
1793 return CAST_FROM_FN_PTR(void*, UserHandler);
1794 }
1795
1796 extern "C" {
1797 typedef void (*sa_handler_t)(int);
1798 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1799 }
1800
1801 void* os::signal(int signal_number, void* handler) {
1802 struct sigaction sigAct, oldSigAct;
1803
1804 sigfillset(&(sigAct.sa_mask));
1805 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1806 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1807
1808 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1809 // -1 means registration failed
1810 return (void *)-1;
1811 }
1812
1813 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1814 }
1815
1816 void os::signal_raise(int signal_number) {
1817 ::raise(signal_number);
1818 }
1819
1820 // The following code is moved from os.cpp for making this
1821 // code platform specific, which it is by its very nature.
1822
1823 // Will be modified when max signal is changed to be dynamic
1824 int os::sigexitnum_pd() {
1825 return NSIG;
1826 }
1827
1828 // a counter for each possible signal value
1829 static volatile jint pending_signals[NSIG+1] = { 0 };
1830 static Semaphore* sig_sem = NULL;
1831
1832 static void jdk_misc_signal_init() {
1833 // Initialize signal structures
1834 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1835
1836 // Initialize signal semaphore
1837 sig_sem = new Semaphore();
1838 }
1839
1840 void os::signal_notify(int sig) {
1841 if (sig_sem != NULL) {
1842 Atomic::inc(&pending_signals[sig]);
1843 sig_sem->signal();
1844 } else {
1845 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1846 // initialization isn't called.
1847 assert(ReduceSignalUsage, "signal semaphore should be created");
1848 }
1849 }
1850
1851 static int check_pending_signals() {
1852 for (;;) {
1853 for (int i = 0; i < NSIG + 1; i++) {
1854 jint n = pending_signals[i];
1855 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1856 return i;
1857 }
1858 }
1859 JavaThread *thread = JavaThread::current();
1860 ThreadBlockInVM tbivm(thread);
1861
1862 bool threadIsSuspended;
1863 do {
1864 thread->set_suspend_equivalent();
1865 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1866 sig_sem->wait();
1867
1868 // were we externally suspended while we were waiting?
1869 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1870 if (threadIsSuspended) {
1871 // The semaphore has been incremented, but while we were waiting
1872 // another thread suspended us. We don't want to continue running
1873 // while suspended because that would surprise the thread that
1874 // suspended us.
1875 sig_sem->signal();
1876
1877 thread->java_suspend_self();
1878 }
1879 } while (threadIsSuspended);
1880 }
1881 }
1882
1883 int os::signal_wait() {
1884 return check_pending_signals();
1885 }
1886
1887 ////////////////////////////////////////////////////////////////////////////////
1888 // Virtual Memory
1889
1890 int os::vm_page_size() {
1891 // Seems redundant as all get out
1892 assert(os::Bsd::page_size() != -1, "must call os::init");
1893 return os::Bsd::page_size();
1894 }
1895
1896 // Solaris allocates memory by pages.
1897 int os::vm_allocation_granularity() {
1898 assert(os::Bsd::page_size() != -1, "must call os::init");
1899 return os::Bsd::page_size();
1900 }
1901
1902 // Rationale behind this function:
1903 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1904 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1905 // samples for JITted code. Here we create private executable mapping over the code cache
1906 // and then we can use standard (well, almost, as mapping can change) way to provide
1907 // info for the reporting script by storing timestamp and location of symbol
1908 void bsd_wrap_code(char* base, size_t size) {
1909 static volatile jint cnt = 0;
1910
1911 if (!UseOprofile) {
1912 return;
1913 }
1914
1915 char buf[PATH_MAX + 1];
1916 int num = Atomic::add(1, &cnt);
1917
1918 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1919 os::get_temp_directory(), os::current_process_id(), num);
1920 unlink(buf);
1921
1922 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1923
1924 if (fd != -1) {
1925 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1926 if (rv != (off_t)-1) {
1927 if (::write(fd, "", 1) == 1) {
1928 mmap(base, size,
1929 PROT_READ|PROT_WRITE|PROT_EXEC,
1930 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1931 }
1932 }
1933 ::close(fd);
1934 unlink(buf);
1935 }
1936 }
1937
1938 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1939 int err) {
1940 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1941 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1942 os::errno_name(err), err);
1943 }
1944
1945 // NOTE: Bsd kernel does not really reserve the pages for us.
1946 // All it does is to check if there are enough free pages
1947 // left at the time of mmap(). This could be a potential
1948 // problem.
1949 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1950 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1951 #ifdef __OpenBSD__
1952 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1953 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
1954 if (::mprotect(addr, size, prot) == 0) {
1955 return true;
1956 }
1957 #else
1958 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1959 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1960 if (res != (uintptr_t) MAP_FAILED) {
1961 return true;
1962 }
1963 #endif
1964
1965 // Warn about any commit errors we see in non-product builds just
1966 // in case mmap() doesn't work as described on the man page.
1967 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1968
1969 return false;
1970 }
1971
1972 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1973 bool exec) {
1974 // alignment_hint is ignored on this OS
1975 return pd_commit_memory(addr, size, exec);
1976 }
1977
1978 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1979 const char* mesg) {
1980 assert(mesg != NULL, "mesg must be specified");
1981 if (!pd_commit_memory(addr, size, exec)) {
1982 // add extra info in product mode for vm_exit_out_of_memory():
1983 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1984 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1985 }
1986 }
1987
1988 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1989 size_t alignment_hint, bool exec,
1990 const char* mesg) {
1991 // alignment_hint is ignored on this OS
1992 pd_commit_memory_or_exit(addr, size, exec, mesg);
1993 }
1994
1995 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1996 }
1997
1998 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1999 ::madvise(addr, bytes, MADV_DONTNEED);
2000 }
2001
2002 void os::numa_make_global(char *addr, size_t bytes) {
2003 }
2004
2005 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2006 }
2007
2008 bool os::numa_topology_changed() { return false; }
2009
2010 size_t os::numa_get_groups_num() {
2011 return 1;
2012 }
2013
2014 int os::numa_get_group_id() {
2015 return 0;
2016 }
2017
2018 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2019 if (size > 0) {
2020 ids[0] = 0;
2021 return 1;
2022 }
2023 return 0;
2024 }
2025
2026 int os::numa_get_group_id_for_address(const void* address) {
2027 return 0;
2028 }
2029
2030 bool os::get_page_info(char *start, page_info* info) {
2031 return false;
2032 }
2033
2034 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2035 return end;
2036 }
2037
2038
2039 bool os::pd_uncommit_memory(char* addr, size_t size) {
2040 #ifdef __OpenBSD__
2041 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2042 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with PROT_NONE", p2i(addr), p2i(addr+size));
2043 return ::mprotect(addr, size, PROT_NONE) == 0;
2044 #else
2045 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2046 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2047 return res != (uintptr_t) MAP_FAILED;
2048 #endif
2049 }
2050
2051 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2052 return os::commit_memory(addr, size, !ExecMem);
2053 }
2054
2055 // If this is a growable mapping, remove the guard pages entirely by
2056 // munmap()ping them. If not, just call uncommit_memory().
2057 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2058 return os::uncommit_memory(addr, size);
2059 }
2060
2061 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2062 // at 'requested_addr'. If there are existing memory mappings at the same
2063 // location, however, they will be overwritten. If 'fixed' is false,
2064 // 'requested_addr' is only treated as a hint, the return value may or
2065 // may not start from the requested address. Unlike Bsd mmap(), this
2066 // function returns NULL to indicate failure.
2067 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2068 char * addr;
2069 int flags;
2070
2071 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2072 if (fixed) {
2073 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2074 flags |= MAP_FIXED;
2075 }
2076
2077 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2078 // touch an uncommitted page. Otherwise, the read/write might
2079 // succeed if we have enough swap space to back the physical page.
2080 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2081 flags, -1, 0);
2082
2083 return addr == MAP_FAILED ? NULL : addr;
2084 }
2085
2086 static int anon_munmap(char * addr, size_t size) {
2087 return ::munmap(addr, size) == 0;
2088 }
2089
2090 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2091 size_t alignment_hint) {
2092 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2093 }
2094
2095 bool os::pd_release_memory(char* addr, size_t size) {
2096 return anon_munmap(addr, size);
2097 }
2098
2099 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2100 // Bsd wants the mprotect address argument to be page aligned.
2101 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2102
2103 // According to SUSv3, mprotect() should only be used with mappings
2104 // established by mmap(), and mmap() always maps whole pages. Unaligned
2105 // 'addr' likely indicates problem in the VM (e.g. trying to change
2106 // protection of malloc'ed or statically allocated memory). Check the
2107 // caller if you hit this assert.
2108 assert(addr == bottom, "sanity check");
2109
2110 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2111 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(bottom), p2i(bottom+size), prot);
2112 return ::mprotect(bottom, size, prot) == 0;
2113 }
2114
2115 // Set protections specified
2116 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2117 bool is_committed) {
2118 unsigned int p = 0;
2119 switch (prot) {
2120 case MEM_PROT_NONE: p = PROT_NONE; break;
2121 case MEM_PROT_READ: p = PROT_READ; break;
2122 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2123 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2124 default:
2125 ShouldNotReachHere();
2126 }
2127 // is_committed is unused.
2128 return bsd_mprotect(addr, bytes, p);
2129 }
2130
2131 bool os::guard_memory(char* addr, size_t size) {
2132 return bsd_mprotect(addr, size, PROT_NONE);
2133 }
2134
2135 bool os::unguard_memory(char* addr, size_t size) {
2136 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2137 }
2138
2139 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2140 return false;
2141 }
2142
2143 // Large page support
2144
2145 static size_t _large_page_size = 0;
2146
2147 void os::large_page_init() {
2148 }
2149
2150
2151 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2152 fatal("os::reserve_memory_special should not be called on BSD.");
2153 return NULL;
2154 }
2155
2156 bool os::release_memory_special(char* base, size_t bytes) {
2157 fatal("os::release_memory_special should not be called on BSD.");
2158 return false;
2159 }
2160
2161 size_t os::large_page_size() {
2162 return _large_page_size;
2163 }
2164
2165 bool os::can_commit_large_page_memory() {
2166 // Does not matter, we do not support huge pages.
2167 return false;
2168 }
2169
2170 bool os::can_execute_large_page_memory() {
2171 // Does not matter, we do not support huge pages.
2172 return false;
2173 }
2174
2175 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2176 assert(file_desc >= 0, "file_desc is not valid");
2177 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2178 if (result != NULL) {
2179 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2180 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2181 }
2182 }
2183 return result;
2184 }
2185
2186 // Reserve memory at an arbitrary address, only if that area is
2187 // available (and not reserved for something else).
2188
2189 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2190 // Assert only that the size is a multiple of the page size, since
2191 // that's all that mmap requires, and since that's all we really know
2192 // about at this low abstraction level. If we need higher alignment,
2193 // we can either pass an alignment to this method or verify alignment
2194 // in one of the methods further up the call chain. See bug 5044738.
2195 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2196
2197 // Repeatedly allocate blocks until the block is allocated at the
2198 // right spot.
2199
2200 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2201 // if kernel honors the hint then we can return immediately.
2202 char * addr = anon_mmap(requested_addr, bytes, false);
2203 if (addr == requested_addr) {
2204 return requested_addr;
2205 }
2206
2207 if (addr != NULL) {
2208 // mmap() is successful but it fails to reserve at the requested address
2209 anon_munmap(addr, bytes);
2210 }
2211
2212 return NULL;
2213 }
2214
2215 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2216 void os::infinite_sleep() {
2217 while (true) { // sleep forever ...
2218 ::sleep(100); // ... 100 seconds at a time
2219 }
2220 }
2221
2222 // Used to convert frequent JVM_Yield() to nops
2223 bool os::dont_yield() {
2224 return DontYieldALot;
2225 }
2226
2227 void os::naked_yield() {
2228 sched_yield();
2229 }
2230
2231 ////////////////////////////////////////////////////////////////////////////////
2232 // thread priority support
2233
2234 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2235 // only supports dynamic priority, static priority must be zero. For real-time
2236 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2237 // However, for large multi-threaded applications, SCHED_RR is not only slower
2238 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2239 // of 5 runs - Sep 2005).
2240 //
2241 // The following code actually changes the niceness of kernel-thread/LWP. It
2242 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2243 // not the entire user process, and user level threads are 1:1 mapped to kernel
2244 // threads. It has always been the case, but could change in the future. For
2245 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2246 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2247 // (e.g., root privilege or CAP_SYS_NICE capability).
2248
2249 #if !defined(__APPLE__)
2250 int os::java_to_os_priority[CriticalPriority + 1] = {
2251 19, // 0 Entry should never be used
2252
2253 0, // 1 MinPriority
2254 3, // 2
2255 6, // 3
2256
2257 10, // 4
2258 15, // 5 NormPriority
2259 18, // 6
2260
2261 21, // 7
2262 25, // 8
2263 28, // 9 NearMaxPriority
2264
2265 31, // 10 MaxPriority
2266
2267 31 // 11 CriticalPriority
2268 };
2269 #else
2270 // Using Mach high-level priority assignments
2271 int os::java_to_os_priority[CriticalPriority + 1] = {
2272 0, // 0 Entry should never be used (MINPRI_USER)
2273
2274 27, // 1 MinPriority
2275 28, // 2
2276 29, // 3
2277
2278 30, // 4
2279 31, // 5 NormPriority (BASEPRI_DEFAULT)
2280 32, // 6
2281
2282 33, // 7
2283 34, // 8
2284 35, // 9 NearMaxPriority
2285
2286 36, // 10 MaxPriority
2287
2288 36 // 11 CriticalPriority
2289 };
2290 #endif
2291
2292 static int prio_init() {
2293 if (ThreadPriorityPolicy == 1) {
2294 if (geteuid() != 0) {
2295 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2296 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2297 "e.g., being the root user. If the necessary permission is not " \
2298 "possessed, changes to priority will be silently ignored.");
2299 }
2300 }
2301 }
2302 if (UseCriticalJavaThreadPriority) {
2303 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2304 }
2305 return 0;
2306 }
2307
2308 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2309 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2310
2311 #ifdef __OpenBSD__
2312 // OpenBSD pthread_setprio starves low priority threads
2313 return OS_OK;
2314 #elif defined(__FreeBSD__)
2315 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2316 return (ret == 0) ? OS_OK : OS_ERR;
2317 #elif defined(__APPLE__) || defined(__NetBSD__)
2318 struct sched_param sp;
2319 int policy;
2320
2321 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2322 return OS_ERR;
2323 }
2324
2325 sp.sched_priority = newpri;
2326 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2327 return OS_ERR;
2328 }
2329
2330 return OS_OK;
2331 #else
2332 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2333 return (ret == 0) ? OS_OK : OS_ERR;
2334 #endif
2335 }
2336
2337 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2338 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2339 *priority_ptr = java_to_os_priority[NormPriority];
2340 return OS_OK;
2341 }
2342
2343 errno = 0;
2344 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2345 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2346 #elif defined(__APPLE__) || defined(__NetBSD__)
2347 int policy;
2348 struct sched_param sp;
2349
2350 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2351 if (res != 0) {
2352 *priority_ptr = -1;
2353 return OS_ERR;
2354 } else {
2355 *priority_ptr = sp.sched_priority;
2356 return OS_OK;
2357 }
2358 #else
2359 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2360 #endif
2361 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2362 }
2363
2364 ////////////////////////////////////////////////////////////////////////////////
2365 // suspend/resume support
2366
2367 // The low-level signal-based suspend/resume support is a remnant from the
2368 // old VM-suspension that used to be for java-suspension, safepoints etc,
2369 // within hotspot. Currently used by JFR's OSThreadSampler
2370 //
2371 // The remaining code is greatly simplified from the more general suspension
2372 // code that used to be used.
2373 //
2374 // The protocol is quite simple:
2375 // - suspend:
2376 // - sends a signal to the target thread
2377 // - polls the suspend state of the osthread using a yield loop
2378 // - target thread signal handler (SR_handler) sets suspend state
2379 // and blocks in sigsuspend until continued
2380 // - resume:
2381 // - sets target osthread state to continue
2382 // - sends signal to end the sigsuspend loop in the SR_handler
2383 //
2384 // Note that the SR_lock plays no role in this suspend/resume protocol,
2385 // but is checked for NULL in SR_handler as a thread termination indicator.
2386 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2387 //
2388 // Note that resume_clear_context() and suspend_save_context() are needed
2389 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2390 // which in part is used by:
2391 // - Forte Analyzer: AsyncGetCallTrace()
2392 // - StackBanging: get_frame_at_stack_banging_point()
2393
2394 static void resume_clear_context(OSThread *osthread) {
2395 osthread->set_ucontext(NULL);
2396 osthread->set_siginfo(NULL);
2397 }
2398
2399 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2400 osthread->set_ucontext(context);
2401 osthread->set_siginfo(siginfo);
2402 }
2403
2404 // Handler function invoked when a thread's execution is suspended or
2405 // resumed. We have to be careful that only async-safe functions are
2406 // called here (Note: most pthread functions are not async safe and
2407 // should be avoided.)
2408 //
2409 // Note: sigwait() is a more natural fit than sigsuspend() from an
2410 // interface point of view, but sigwait() prevents the signal hander
2411 // from being run. libpthread would get very confused by not having
2412 // its signal handlers run and prevents sigwait()'s use with the
2413 // mutex granting granting signal.
2414 //
2415 // Currently only ever called on the VMThread or JavaThread
2416 //
2417 #ifdef __APPLE__
2418 static OSXSemaphore sr_semaphore;
2419 #else
2420 static PosixSemaphore sr_semaphore;
2421 #endif
2422
2423 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2424 // Save and restore errno to avoid confusing native code with EINTR
2425 // after sigsuspend.
2426 int old_errno = errno;
2427
2428 Thread* thread = Thread::current_or_null_safe();
2429 assert(thread != NULL, "Missing current thread in SR_handler");
2430
2431 // On some systems we have seen signal delivery get "stuck" until the signal
2432 // mask is changed as part of thread termination. Check that the current thread
2433 // has not already terminated (via SR_lock()) - else the following assertion
2434 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2435 // destructor has completed.
2436
2437 if (thread->SR_lock() == NULL) {
2438 return;
2439 }
2440
2441 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2442
2443 OSThread* osthread = thread->osthread();
2444
2445 os::SuspendResume::State current = osthread->sr.state();
2446 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2447 suspend_save_context(osthread, siginfo, context);
2448
2449 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2450 os::SuspendResume::State state = osthread->sr.suspended();
2451 if (state == os::SuspendResume::SR_SUSPENDED) {
2452 sigset_t suspend_set; // signals for sigsuspend()
2453
2454 // get current set of blocked signals and unblock resume signal
2455 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2456 sigdelset(&suspend_set, SR_signum);
2457
2458 sr_semaphore.signal();
2459 // wait here until we are resumed
2460 while (1) {
2461 sigsuspend(&suspend_set);
2462
2463 os::SuspendResume::State result = osthread->sr.running();
2464 if (result == os::SuspendResume::SR_RUNNING) {
2465 sr_semaphore.signal();
2466 break;
2467 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2468 ShouldNotReachHere();
2469 }
2470 }
2471
2472 } else if (state == os::SuspendResume::SR_RUNNING) {
2473 // request was cancelled, continue
2474 } else {
2475 ShouldNotReachHere();
2476 }
2477
2478 resume_clear_context(osthread);
2479 } else if (current == os::SuspendResume::SR_RUNNING) {
2480 // request was cancelled, continue
2481 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2482 // ignore
2483 } else {
2484 // ignore
2485 }
2486
2487 errno = old_errno;
2488 }
2489
2490
2491 static int SR_initialize() {
2492 struct sigaction act;
2493 char *s;
2494 // Get signal number to use for suspend/resume
2495 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2496 int sig = ::strtol(s, 0, 10);
2497 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2498 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2499 SR_signum = sig;
2500 } else {
2501 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2502 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2503 }
2504 }
2505
2506 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2507 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2508
2509 sigemptyset(&SR_sigset);
2510 sigaddset(&SR_sigset, SR_signum);
2511
2512 // Set up signal handler for suspend/resume
2513 act.sa_flags = SA_RESTART|SA_SIGINFO;
2514 act.sa_handler = (void (*)(int)) SR_handler;
2515
2516 // SR_signum is blocked by default.
2517 // 4528190 - We also need to block pthread restart signal (32 on all
2518 // supported Bsd platforms). Note that BsdThreads need to block
2519 // this signal for all threads to work properly. So we don't have
2520 // to use hard-coded signal number when setting up the mask.
2521 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2522
2523 if (sigaction(SR_signum, &act, 0) == -1) {
2524 return -1;
2525 }
2526
2527 // Save signal flag
2528 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2529 return 0;
2530 }
2531
2532 static int sr_notify(OSThread* osthread) {
2533 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2534 assert_status(status == 0, status, "pthread_kill");
2535 return status;
2536 }
2537
2538 // "Randomly" selected value for how long we want to spin
2539 // before bailing out on suspending a thread, also how often
2540 // we send a signal to a thread we want to resume
2541 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2542 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2543
2544 // returns true on success and false on error - really an error is fatal
2545 // but this seems the normal response to library errors
2546 static bool do_suspend(OSThread* osthread) {
2547 assert(osthread->sr.is_running(), "thread should be running");
2548 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2549
2550 // mark as suspended and send signal
2551 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2552 // failed to switch, state wasn't running?
2553 ShouldNotReachHere();
2554 return false;
2555 }
2556
2557 if (sr_notify(osthread) != 0) {
2558 ShouldNotReachHere();
2559 }
2560
2561 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2562 while (true) {
2563 if (sr_semaphore.timedwait(2)) {
2564 break;
2565 } else {
2566 // timeout
2567 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2568 if (cancelled == os::SuspendResume::SR_RUNNING) {
2569 return false;
2570 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2571 // make sure that we consume the signal on the semaphore as well
2572 sr_semaphore.wait();
2573 break;
2574 } else {
2575 ShouldNotReachHere();
2576 return false;
2577 }
2578 }
2579 }
2580
2581 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2582 return true;
2583 }
2584
2585 static void do_resume(OSThread* osthread) {
2586 assert(osthread->sr.is_suspended(), "thread should be suspended");
2587 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2588
2589 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2590 // failed to switch to WAKEUP_REQUEST
2591 ShouldNotReachHere();
2592 return;
2593 }
2594
2595 while (true) {
2596 if (sr_notify(osthread) == 0) {
2597 if (sr_semaphore.timedwait(2)) {
2598 if (osthread->sr.is_running()) {
2599 return;
2600 }
2601 }
2602 } else {
2603 ShouldNotReachHere();
2604 }
2605 }
2606
2607 guarantee(osthread->sr.is_running(), "Must be running!");
2608 }
2609
2610 ///////////////////////////////////////////////////////////////////////////////////
2611 // signal handling (except suspend/resume)
2612
2613 // This routine may be used by user applications as a "hook" to catch signals.
2614 // The user-defined signal handler must pass unrecognized signals to this
2615 // routine, and if it returns true (non-zero), then the signal handler must
2616 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2617 // routine will never retun false (zero), but instead will execute a VM panic
2618 // routine kill the process.
2619 //
2620 // If this routine returns false, it is OK to call it again. This allows
2621 // the user-defined signal handler to perform checks either before or after
2622 // the VM performs its own checks. Naturally, the user code would be making
2623 // a serious error if it tried to handle an exception (such as a null check
2624 // or breakpoint) that the VM was generating for its own correct operation.
2625 //
2626 // This routine may recognize any of the following kinds of signals:
2627 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2628 // It should be consulted by handlers for any of those signals.
2629 //
2630 // The caller of this routine must pass in the three arguments supplied
2631 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2632 // field of the structure passed to sigaction(). This routine assumes that
2633 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2634 //
2635 // Note that the VM will print warnings if it detects conflicting signal
2636 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2637 //
2638 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2639 void* ucontext,
2640 int abort_if_unrecognized);
2641
2642 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2643 assert(info != NULL && uc != NULL, "it must be old kernel");
2644 int orig_errno = errno; // Preserve errno value over signal handler.
2645 JVM_handle_bsd_signal(sig, info, uc, true);
2646 errno = orig_errno;
2647 }
2648
2649
2650 // This boolean allows users to forward their own non-matching signals
2651 // to JVM_handle_bsd_signal, harmlessly.
2652 bool os::Bsd::signal_handlers_are_installed = false;
2653
2654 // For signal-chaining
2655 bool os::Bsd::libjsig_is_loaded = false;
2656 typedef struct sigaction *(*get_signal_t)(int);
2657 get_signal_t os::Bsd::get_signal_action = NULL;
2658
2659 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2660 struct sigaction *actp = NULL;
2661
2662 if (libjsig_is_loaded) {
2663 // Retrieve the old signal handler from libjsig
2664 actp = (*get_signal_action)(sig);
2665 }
2666 if (actp == NULL) {
2667 // Retrieve the preinstalled signal handler from jvm
2668 actp = os::Posix::get_preinstalled_handler(sig);
2669 }
2670
2671 return actp;
2672 }
2673
2674 static bool call_chained_handler(struct sigaction *actp, int sig,
2675 siginfo_t *siginfo, void *context) {
2676 // Call the old signal handler
2677 if (actp->sa_handler == SIG_DFL) {
2678 // It's more reasonable to let jvm treat it as an unexpected exception
2679 // instead of taking the default action.
2680 return false;
2681 } else if (actp->sa_handler != SIG_IGN) {
2682 if ((actp->sa_flags & SA_NODEFER) == 0) {
2683 // automaticlly block the signal
2684 sigaddset(&(actp->sa_mask), sig);
2685 }
2686
2687 sa_handler_t hand;
2688 sa_sigaction_t sa;
2689 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2690 // retrieve the chained handler
2691 if (siginfo_flag_set) {
2692 sa = actp->sa_sigaction;
2693 } else {
2694 hand = actp->sa_handler;
2695 }
2696
2697 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2698 actp->sa_handler = SIG_DFL;
2699 }
2700
2701 // try to honor the signal mask
2702 sigset_t oset;
2703 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2704
2705 // call into the chained handler
2706 if (siginfo_flag_set) {
2707 (*sa)(sig, siginfo, context);
2708 } else {
2709 (*hand)(sig);
2710 }
2711
2712 // restore the signal mask
2713 pthread_sigmask(SIG_SETMASK, &oset, 0);
2714 }
2715 // Tell jvm's signal handler the signal is taken care of.
2716 return true;
2717 }
2718
2719 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2720 bool chained = false;
2721 // signal-chaining
2722 if (UseSignalChaining) {
2723 struct sigaction *actp = get_chained_signal_action(sig);
2724 if (actp != NULL) {
2725 chained = call_chained_handler(actp, sig, siginfo, context);
2726 }
2727 }
2728 return chained;
2729 }
2730
2731 // for diagnostic
2732 int sigflags[NSIG];
2733
2734 int os::Bsd::get_our_sigflags(int sig) {
2735 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2736 return sigflags[sig];
2737 }
2738
2739 void os::Bsd::set_our_sigflags(int sig, int flags) {
2740 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2741 if (sig > 0 && sig < NSIG) {
2742 sigflags[sig] = flags;
2743 }
2744 }
2745
2746 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2747 // Check for overwrite.
2748 struct sigaction oldAct;
2749 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2750
2751 void* oldhand = oldAct.sa_sigaction
2752 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2753 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2754 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2755 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2756 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2757 if (AllowUserSignalHandlers || !set_installed) {
2758 // Do not overwrite; user takes responsibility to forward to us.
2759 return;
2760 } else if (UseSignalChaining) {
2761 // save the old handler in jvm
2762 os::Posix::save_preinstalled_handler(sig, oldAct);
2763 // libjsig also interposes the sigaction() call below and saves the
2764 // old sigaction on it own.
2765 } else {
2766 fatal("Encountered unexpected pre-existing sigaction handler "
2767 "%#lx for signal %d.", (long)oldhand, sig);
2768 }
2769 }
2770
2771 struct sigaction sigAct;
2772 sigfillset(&(sigAct.sa_mask));
2773 sigAct.sa_handler = SIG_DFL;
2774 if (!set_installed) {
2775 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2776 } else {
2777 sigAct.sa_sigaction = signalHandler;
2778 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2779 }
2780 #ifdef __APPLE__
2781 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2782 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2783 // if the signal handler declares it will handle it on alternate stack.
2784 // Notice we only declare we will handle it on alt stack, but we are not
2785 // actually going to use real alt stack - this is just a workaround.
2786 // Please see ux_exception.c, method catch_mach_exception_raise for details
2787 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2788 if (sig == SIGSEGV) {
2789 sigAct.sa_flags |= SA_ONSTACK;
2790 }
2791 #endif
2792
2793 // Save flags, which are set by ours
2794 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2795 sigflags[sig] = sigAct.sa_flags;
2796
2797 int ret = sigaction(sig, &sigAct, &oldAct);
2798 assert(ret == 0, "check");
2799
2800 void* oldhand2 = oldAct.sa_sigaction
2801 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2802 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2803 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2804 }
2805
2806 // install signal handlers for signals that HotSpot needs to
2807 // handle in order to support Java-level exception handling.
2808
2809 void os::Bsd::install_signal_handlers() {
2810 if (!signal_handlers_are_installed) {
2811 signal_handlers_are_installed = true;
2812
2813 // signal-chaining
2814 typedef void (*signal_setting_t)();
2815 signal_setting_t begin_signal_setting = NULL;
2816 signal_setting_t end_signal_setting = NULL;
2817 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2818 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2819 if (begin_signal_setting != NULL) {
2820 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2821 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2822 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2823 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2824 libjsig_is_loaded = true;
2825 assert(UseSignalChaining, "should enable signal-chaining");
2826 }
2827 if (libjsig_is_loaded) {
2828 // Tell libjsig jvm is setting signal handlers
2829 (*begin_signal_setting)();
2830 }
2831
2832 set_signal_handler(SIGSEGV, true);
2833 set_signal_handler(SIGPIPE, true);
2834 set_signal_handler(SIGBUS, true);
2835 set_signal_handler(SIGILL, true);
2836 set_signal_handler(SIGFPE, true);
2837 set_signal_handler(SIGXFSZ, true);
2838
2839 #if defined(__APPLE__)
2840 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2841 // signals caught and handled by the JVM. To work around this, we reset the mach task
2842 // signal handler that's placed on our process by CrashReporter. This disables
2843 // CrashReporter-based reporting.
2844 //
2845 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2846 // on caught fatal signals.
2847 //
2848 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2849 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2850 // exception handling, while leaving the standard BSD signal handlers functional.
2851 kern_return_t kr;
2852 kr = task_set_exception_ports(mach_task_self(),
2853 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2854 MACH_PORT_NULL,
2855 EXCEPTION_STATE_IDENTITY,
2856 MACHINE_THREAD_STATE);
2857
2858 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2859 #endif
2860
2861 if (libjsig_is_loaded) {
2862 // Tell libjsig jvm finishes setting signal handlers
2863 (*end_signal_setting)();
2864 }
2865
2866 // We don't activate signal checker if libjsig is in place, we trust ourselves
2867 // and if UserSignalHandler is installed all bets are off
2868 if (CheckJNICalls) {
2869 if (libjsig_is_loaded) {
2870 log_debug(jni, resolve)("Info: libjsig is activated, all active signal checking is disabled");
2871 check_signals = false;
2872 }
2873 if (AllowUserSignalHandlers) {
2874 log_debug(jni, resolve)("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2875 check_signals = false;
2876 }
2877 }
2878 }
2879 }
2880
2881
2882 /////
2883 // glibc on Bsd platform uses non-documented flag
2884 // to indicate, that some special sort of signal
2885 // trampoline is used.
2886 // We will never set this flag, and we should
2887 // ignore this flag in our diagnostic
2888 #ifdef SIGNIFICANT_SIGNAL_MASK
2889 #undef SIGNIFICANT_SIGNAL_MASK
2890 #endif
2891 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2892
2893 static const char* get_signal_handler_name(address handler,
2894 char* buf, int buflen) {
2895 int offset;
2896 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2897 if (found) {
2898 // skip directory names
2899 const char *p1, *p2;
2900 p1 = buf;
2901 size_t len = strlen(os::file_separator());
2902 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2903 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2904 } else {
2905 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2906 }
2907 return buf;
2908 }
2909
2910 static void print_signal_handler(outputStream* st, int sig,
2911 char* buf, size_t buflen) {
2912 struct sigaction sa;
2913
2914 sigaction(sig, NULL, &sa);
2915
2916 // See comment for SIGNIFICANT_SIGNAL_MASK define
2917 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2918
2919 st->print("%s: ", os::exception_name(sig, buf, buflen));
2920
2921 address handler = (sa.sa_flags & SA_SIGINFO)
2922 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2923 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2924
2925 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2926 st->print("SIG_DFL");
2927 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2928 st->print("SIG_IGN");
2929 } else {
2930 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2931 }
2932
2933 st->print(", sa_mask[0]=");
2934 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2935
2936 address rh = VMError::get_resetted_sighandler(sig);
2937 // May be, handler was resetted by VMError?
2938 if (rh != NULL) {
2939 handler = rh;
2940 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2941 }
2942
2943 st->print(", sa_flags=");
2944 os::Posix::print_sa_flags(st, sa.sa_flags);
2945
2946 // Check: is it our handler?
2947 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2948 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2949 // It is our signal handler
2950 // check for flags, reset system-used one!
2951 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2952 st->print(
2953 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2954 os::Bsd::get_our_sigflags(sig));
2955 }
2956 }
2957 st->cr();
2958 }
2959
2960
2961 #define DO_SIGNAL_CHECK(sig) \
2962 do { \
2963 if (!sigismember(&check_signal_done, sig)) { \
2964 os::Bsd::check_signal_handler(sig); \
2965 } \
2966 } while (0)
2967
2968 // This method is a periodic task to check for misbehaving JNI applications
2969 // under CheckJNI, we can add any periodic checks here
2970
2971 void os::run_periodic_checks() {
2972
2973 if (check_signals == false) return;
2974
2975 // SEGV and BUS if overridden could potentially prevent
2976 // generation of hs*.log in the event of a crash, debugging
2977 // such a case can be very challenging, so we absolutely
2978 // check the following for a good measure:
2979 DO_SIGNAL_CHECK(SIGSEGV);
2980 DO_SIGNAL_CHECK(SIGILL);
2981 DO_SIGNAL_CHECK(SIGFPE);
2982 DO_SIGNAL_CHECK(SIGBUS);
2983 DO_SIGNAL_CHECK(SIGPIPE);
2984 DO_SIGNAL_CHECK(SIGXFSZ);
2985
2986
2987 // ReduceSignalUsage allows the user to override these handlers
2988 // see comments at the very top and jvm_md.h
2989 if (!ReduceSignalUsage) {
2990 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
2991 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
2992 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
2993 DO_SIGNAL_CHECK(BREAK_SIGNAL);
2994 }
2995
2996 DO_SIGNAL_CHECK(SR_signum);
2997 }
2998
2999 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3000
3001 static os_sigaction_t os_sigaction = NULL;
3002
3003 void os::Bsd::check_signal_handler(int sig) {
3004 char buf[O_BUFLEN];
3005 address jvmHandler = NULL;
3006
3007
3008 struct sigaction act;
3009 if (os_sigaction == NULL) {
3010 // only trust the default sigaction, in case it has been interposed
3011 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3012 if (os_sigaction == NULL) return;
3013 }
3014
3015 os_sigaction(sig, (struct sigaction*)NULL, &act);
3016
3017
3018 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3019
3020 address thisHandler = (act.sa_flags & SA_SIGINFO)
3021 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3022 : CAST_FROM_FN_PTR(address, act.sa_handler);
3023
3024
3025 switch (sig) {
3026 case SIGSEGV:
3027 case SIGBUS:
3028 case SIGFPE:
3029 case SIGPIPE:
3030 case SIGILL:
3031 case SIGXFSZ:
3032 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3033 break;
3034
3035 case SHUTDOWN1_SIGNAL:
3036 case SHUTDOWN2_SIGNAL:
3037 case SHUTDOWN3_SIGNAL:
3038 case BREAK_SIGNAL:
3039 jvmHandler = (address)user_handler();
3040 break;
3041
3042 default:
3043 if (sig == SR_signum) {
3044 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3045 } else {
3046 return;
3047 }
3048 break;
3049 }
3050
3051 if (thisHandler != jvmHandler) {
3052 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3053 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3054 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3055 // No need to check this sig any longer
3056 sigaddset(&check_signal_done, sig);
3057 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3058 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3059 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3060 exception_name(sig, buf, O_BUFLEN));
3061 }
3062 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3063 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3064 tty->print("expected:");
3065 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3066 tty->cr();
3067 tty->print(" found:");
3068 os::Posix::print_sa_flags(tty, act.sa_flags);
3069 tty->cr();
3070 // No need to check this sig any longer
3071 sigaddset(&check_signal_done, sig);
3072 }
3073
3074 // Dump all the signal
3075 if (sigismember(&check_signal_done, sig)) {
3076 print_signal_handlers(tty, buf, O_BUFLEN);
3077 }
3078 }
3079
3080 extern void report_error(char* file_name, int line_no, char* title,
3081 char* format, ...);
3082
3083 // this is called _before_ the most of global arguments have been parsed
3084 void os::init(void) {
3085 char dummy; // used to get a guess on initial stack address
3086
3087 clock_tics_per_sec = CLK_TCK;
3088
3089 init_random(1234567);
3090
3091 Bsd::set_page_size(getpagesize());
3092 if (Bsd::page_size() == -1) {
3093 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3094 }
3095 init_page_sizes((size_t) Bsd::page_size());
3096
3097 Bsd::initialize_system_info();
3098
3099 // _main_thread points to the thread that created/loaded the JVM.
3100 Bsd::_main_thread = pthread_self();
3101
3102 Bsd::clock_init();
3103 initial_time_count = javaTimeNanos();
3104
3105 os::Posix::init();
3106 }
3107
3108 // To install functions for atexit system call
3109 extern "C" {
3110 static void perfMemory_exit_helper() {
3111 perfMemory_exit();
3112 }
3113 }
3114
3115 // this is called _after_ the global arguments have been parsed
3116 jint os::init_2(void) {
3117
3118 // This could be set after os::Posix::init() but all platforms
3119 // have to set it the same so we have to mirror Solaris.
3120 DEBUG_ONLY(os::set_mutex_init_done();)
3121
3122 os::Posix::init_2();
3123
3124 // initialize suspend/resume support - must do this before signal_sets_init()
3125 if (SR_initialize() != 0) {
3126 perror("SR_initialize failed");
3127 return JNI_ERR;
3128 }
3129
3130 Bsd::signal_sets_init();
3131 Bsd::install_signal_handlers();
3132 // Initialize data for jdk.internal.misc.Signal
3133 if (!ReduceSignalUsage) {
3134 jdk_misc_signal_init();
3135 }
3136
3137 // Check and sets minimum stack sizes against command line options
3138 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3139 return JNI_ERR;
3140 }
3141
3142 if (MaxFDLimit) {
3143 // set the number of file descriptors to max. print out error
3144 // if getrlimit/setrlimit fails but continue regardless.
3145 struct rlimit nbr_files;
3146 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3147 if (status != 0) {
3148 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3149 } else {
3150 nbr_files.rlim_cur = nbr_files.rlim_max;
3151
3152 #ifdef __APPLE__
3153 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3154 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3155 // be used instead
3156 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3157 #endif
3158
3159 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3160 if (status != 0) {
3161 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3162 }
3163 }
3164 }
3165
3166 // at-exit methods are called in the reverse order of their registration.
3167 // atexit functions are called on return from main or as a result of a
3168 // call to exit(3C). There can be only 32 of these functions registered
3169 // and atexit() does not set errno.
3170
3171 if (PerfAllowAtExitRegistration) {
3172 // only register atexit functions if PerfAllowAtExitRegistration is set.
3173 // atexit functions can be delayed until process exit time, which
3174 // can be problematic for embedded VM situations. Embedded VMs should
3175 // call DestroyJavaVM() to assure that VM resources are released.
3176
3177 // note: perfMemory_exit_helper atexit function may be removed in
3178 // the future if the appropriate cleanup code can be added to the
3179 // VM_Exit VMOperation's doit method.
3180 if (atexit(perfMemory_exit_helper) != 0) {
3181 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3182 }
3183 }
3184
3185 // initialize thread priority policy
3186 prio_init();
3187
3188 #ifdef __APPLE__
3189 // dynamically link to objective c gc registration
3190 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3191 if (handleLibObjc != NULL) {
3192 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3193 }
3194 #endif
3195
3196 return JNI_OK;
3197 }
3198
3199 // Mark the polling page as unreadable
3200 void os::make_polling_page_unreadable(void) {
3201 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3202 fatal("Could not disable polling page");
3203 }
3204 }
3205
3206 // Mark the polling page as readable
3207 void os::make_polling_page_readable(void) {
3208 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3209 fatal("Could not enable polling page");
3210 }
3211 }
3212
3213 int os::active_processor_count() {
3214 // User has overridden the number of active processors
3215 if (ActiveProcessorCount > 0) {
3216 log_trace(os)("active_processor_count: "
3217 "active processor count set by user : %d",
3218 ActiveProcessorCount);
3219 return ActiveProcessorCount;
3220 }
3221
3222 return _processor_count;
3223 }
3224
3225 #ifdef __APPLE__
3226 uint os::processor_id() {
3227 static volatile int* volatile apic_to_cpu_mapping = NULL;
3228 static volatile int next_cpu_id = 0;
3229
3230 volatile int* mapping = OrderAccess::load_acquire(&apic_to_cpu_mapping);
3231 if (mapping == NULL) {
3232 // Calculate possible number space for APIC ids. This space is not necessarily
3233 // in the range [0, number_of_cpus).
3234 uint total_bits = 0;
3235 for (uint i = 0;; ++i) {
3236 uint eax = 0xb; // Query topology leaf
3237 uint ebx;
3238 uint ecx = i;
3239 uint edx;
3240
3241 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3242
3243 uint level_type = (ecx >> 8) & 0xFF;
3244 if (level_type == 0) {
3245 // Invalid level; end of topology
3246 break;
3247 }
3248 uint level_apic_id_shift = eax & ((1u << 5) - 1);
3249 total_bits += level_apic_id_shift;
3250 }
3251
3252 uint max_apic_ids = 1u << total_bits;
3253 mapping = NEW_C_HEAP_ARRAY(int, max_apic_ids, mtInternal);
3254
3255 for (uint i = 0; i < max_apic_ids; ++i) {
3256 mapping[i] = -1;
3257 }
3258
3259 if (!Atomic::replace_if_null(mapping, &apic_to_cpu_mapping)) {
3260 FREE_C_HEAP_ARRAY(int, mapping);
3261 mapping = OrderAccess::load_acquire(&apic_to_cpu_mapping);
3262 }
3263 }
3264
3265 uint eax = 0xb;
3266 uint ebx;
3267 uint ecx = 0;
3268 uint edx;
3269
3270 asm ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3271
3272 // Map from APIC id to a unique logical processor ID in the expected
3273 // [0, num_processors) range.
3274
3275 uint apic_id = edx;
3276 int cpu_id = Atomic::load(&mapping[apic_id]);
3277
3278 while (cpu_id < 0) {
3279 if (Atomic::cmpxchg(-2, &mapping[apic_id], -1)) {
3280 Atomic::store(Atomic::add(1, &next_cpu_id) - 1, &mapping[apic_id]);
3281 }
3282 cpu_id = Atomic::load(&mapping[apic_id]);
3283 }
3284
3285 return (uint)cpu_id;
3286 }
3287 #endif
3288
3289 void os::set_native_thread_name(const char *name) {
3290 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3291 // This is only supported in Snow Leopard and beyond
3292 if (name != NULL) {
3293 // Add a "Java: " prefix to the name
3294 char buf[MAXTHREADNAMESIZE];
3295 snprintf(buf, sizeof(buf), "Java: %s", name);
3296 pthread_setname_np(buf);
3297 }
3298 #endif
3299 }
3300
3301 bool os::bind_to_processor(uint processor_id) {
3302 // Not yet implemented.
3303 return false;
3304 }
3305
3306 void os::SuspendedThreadTask::internal_do_task() {
3307 if (do_suspend(_thread->osthread())) {
3308 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3309 do_task(context);
3310 do_resume(_thread->osthread());
3311 }
3312 }
3313
3314 ////////////////////////////////////////////////////////////////////////////////
3315 // debug support
3316
3317 bool os::find(address addr, outputStream* st) {
3318 Dl_info dlinfo;
3319 memset(&dlinfo, 0, sizeof(dlinfo));
3320 if (dladdr(addr, &dlinfo) != 0) {
3321 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3322 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3323 st->print("%s+%#x", dlinfo.dli_sname,
3324 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3325 } else if (dlinfo.dli_fbase != NULL) {
3326 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3327 } else {
3328 st->print("<absolute address>");
3329 }
3330 if (dlinfo.dli_fname != NULL) {
3331 st->print(" in %s", dlinfo.dli_fname);
3332 }
3333 if (dlinfo.dli_fbase != NULL) {
3334 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3335 }
3336 st->cr();
3337
3338 if (Verbose) {
3339 // decode some bytes around the PC
3340 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3341 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3342 address lowest = (address) dlinfo.dli_sname;
3343 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3344 if (begin < lowest) begin = lowest;
3345 Dl_info dlinfo2;
3346 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3347 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3348 end = (address) dlinfo2.dli_saddr;
3349 }
3350 Disassembler::decode(begin, end, st);
3351 }
3352 return true;
3353 }
3354 return false;
3355 }
3356
3357 ////////////////////////////////////////////////////////////////////////////////
3358 // misc
3359
3360 // This does not do anything on Bsd. This is basically a hook for being
3361 // able to use structured exception handling (thread-local exception filters)
3362 // on, e.g., Win32.
3363 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3364 const methodHandle& method, JavaCallArguments* args,
3365 Thread* thread) {
3366 f(value, method, args, thread);
3367 }
3368
3369 void os::print_statistics() {
3370 }
3371
3372 bool os::message_box(const char* title, const char* message) {
3373 int i;
3374 fdStream err(defaultStream::error_fd());
3375 for (i = 0; i < 78; i++) err.print_raw("=");
3376 err.cr();
3377 err.print_raw_cr(title);
3378 for (i = 0; i < 78; i++) err.print_raw("-");
3379 err.cr();
3380 err.print_raw_cr(message);
3381 for (i = 0; i < 78; i++) err.print_raw("=");
3382 err.cr();
3383
3384 char buf[16];
3385 // Prevent process from exiting upon "read error" without consuming all CPU
3386 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3387
3388 return buf[0] == 'y' || buf[0] == 'Y';
3389 }
3390
3391 static inline struct timespec get_mtime(const char* filename) {
3392 struct stat st;
3393 int ret = os::stat(filename, &st);
3394 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3395 #ifdef __APPLE__
3396 return st.st_mtimespec;
3397 #else
3398 return st.st_mtim;
3399 #endif
3400 }
3401
3402 int os::compare_file_modified_times(const char* file1, const char* file2) {
3403 struct timespec filetime1 = get_mtime(file1);
3404 struct timespec filetime2 = get_mtime(file2);
3405 int diff = filetime1.tv_sec - filetime2.tv_sec;
3406 if (diff == 0) {
3407 return filetime1.tv_nsec - filetime2.tv_nsec;
3408 }
3409 return diff;
3410 }
3411
3412 // Is a (classpath) directory empty?
3413 bool os::dir_is_empty(const char* path) {
3414 DIR *dir = NULL;
3415 struct dirent *ptr;
3416
3417 dir = opendir(path);
3418 if (dir == NULL) return true;
3419
3420 // Scan the directory
3421 bool result = true;
3422 while (result && (ptr = readdir(dir)) != NULL) {
3423 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3424 result = false;
3425 }
3426 }
3427 closedir(dir);
3428 return result;
3429 }
3430
3431 // This code originates from JDK's sysOpen and open64_w
3432 // from src/solaris/hpi/src/system_md.c
3433
3434 int os::open(const char *path, int oflag, int mode) {
3435 if (strlen(path) > MAX_PATH - 1) {
3436 errno = ENAMETOOLONG;
3437 return -1;
3438 }
3439 int fd;
3440
3441 fd = ::open(path, oflag, mode);
3442 if (fd == -1) return -1;
3443
3444 // If the open succeeded, the file might still be a directory
3445 {
3446 struct stat buf;
3447 int ret = ::fstat(fd, &buf);
3448 int st_mode = buf.st_mode;
3449
3450 if (ret != -1) {
3451 if ((st_mode & S_IFMT) == S_IFDIR) {
3452 errno = EISDIR;
3453 ::close(fd);
3454 return -1;
3455 }
3456 } else {
3457 ::close(fd);
3458 return -1;
3459 }
3460 }
3461
3462 // All file descriptors that are opened in the JVM and not
3463 // specifically destined for a subprocess should have the
3464 // close-on-exec flag set. If we don't set it, then careless 3rd
3465 // party native code might fork and exec without closing all
3466 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3467 // UNIXProcess.c), and this in turn might:
3468 //
3469 // - cause end-of-file to fail to be detected on some file
3470 // descriptors, resulting in mysterious hangs, or
3471 //
3472 // - might cause an fopen in the subprocess to fail on a system
3473 // suffering from bug 1085341.
3474 //
3475 // (Yes, the default setting of the close-on-exec flag is a Unix
3476 // design flaw)
3477 //
3478 // See:
3479 // 1085341: 32-bit stdio routines should support file descriptors >255
3480 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3481 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3482 //
3483 #ifdef FD_CLOEXEC
3484 {
3485 int flags = ::fcntl(fd, F_GETFD);
3486 if (flags != -1) {
3487 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3488 }
3489 }
3490 #endif
3491
3492 return fd;
3493 }
3494
3495
3496 // create binary file, rewriting existing file if required
3497 int os::create_binary_file(const char* path, bool rewrite_existing) {
3498 int oflags = O_WRONLY | O_CREAT;
3499 if (!rewrite_existing) {
3500 oflags |= O_EXCL;
3501 }
3502 return ::open(path, oflags, S_IREAD | S_IWRITE);
3503 }
3504
3505 // return current position of file pointer
3506 jlong os::current_file_offset(int fd) {
3507 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3508 }
3509
3510 // move file pointer to the specified offset
3511 jlong os::seek_to_file_offset(int fd, jlong offset) {
3512 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3513 }
3514
3515 // This code originates from JDK's sysAvailable
3516 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3517
3518 int os::available(int fd, jlong *bytes) {
3519 jlong cur, end;
3520 int mode;
3521 struct stat buf;
3522
3523 if (::fstat(fd, &buf) >= 0) {
3524 mode = buf.st_mode;
3525 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3526 int n;
3527 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3528 *bytes = n;
3529 return 1;
3530 }
3531 }
3532 }
3533 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3534 return 0;
3535 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3536 return 0;
3537 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3538 return 0;
3539 }
3540 *bytes = end - cur;
3541 return 1;
3542 }
3543
3544 // Map a block of memory.
3545 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3546 char *addr, size_t bytes, bool read_only,
3547 bool allow_exec) {
3548 int prot;
3549 int flags;
3550
3551 if (read_only) {
3552 prot = PROT_READ;
3553 flags = MAP_SHARED;
3554 } else {
3555 prot = PROT_READ | PROT_WRITE;
3556 flags = MAP_PRIVATE;
3557 }
3558
3559 if (allow_exec) {
3560 prot |= PROT_EXEC;
3561 }
3562
3563 if (addr != NULL) {
3564 flags |= MAP_FIXED;
3565 }
3566
3567 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3568 fd, file_offset);
3569 if (mapped_address == MAP_FAILED) {
3570 return NULL;
3571 }
3572 return mapped_address;
3573 }
3574
3575
3576 // Remap a block of memory.
3577 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3578 char *addr, size_t bytes, bool read_only,
3579 bool allow_exec) {
3580 // same as map_memory() on this OS
3581 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3582 allow_exec);
3583 }
3584
3585
3586 // Unmap a block of memory.
3587 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3588 return munmap(addr, bytes) == 0;
3589 }
3590
3591 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3592 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3593 // of a thread.
3594 //
3595 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3596 // the fast estimate available on the platform.
3597
3598 jlong os::current_thread_cpu_time() {
3599 #ifdef __APPLE__
3600 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3601 #else
3602 Unimplemented();
3603 return 0;
3604 #endif
3605 }
3606
3607 jlong os::thread_cpu_time(Thread* thread) {
3608 #ifdef __APPLE__
3609 return os::thread_cpu_time(thread, true /* user + sys */);
3610 #else
3611 Unimplemented();
3612 return 0;
3613 #endif
3614 }
3615
3616 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3617 #ifdef __APPLE__
3618 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3619 #else
3620 Unimplemented();
3621 return 0;
3622 #endif
3623 }
3624
3625 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3626 #ifdef __APPLE__
3627 struct thread_basic_info tinfo;
3628 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3629 kern_return_t kr;
3630 thread_t mach_thread;
3631
3632 mach_thread = thread->osthread()->thread_id();
3633 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3634 if (kr != KERN_SUCCESS) {
3635 return -1;
3636 }
3637
3638 if (user_sys_cpu_time) {
3639 jlong nanos;
3640 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3641 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3642 return nanos;
3643 } else {
3644 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3645 }
3646 #else
3647 Unimplemented();
3648 return 0;
3649 #endif
3650 }
3651
3652
3653 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3654 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3655 info_ptr->may_skip_backward = false; // elapsed time not wall time
3656 info_ptr->may_skip_forward = false; // elapsed time not wall time
3657 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3658 }
3659
3660 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3661 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3662 info_ptr->may_skip_backward = false; // elapsed time not wall time
3663 info_ptr->may_skip_forward = false; // elapsed time not wall time
3664 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3665 }
3666
3667 bool os::is_thread_cpu_time_supported() {
3668 #ifdef __APPLE__
3669 return true;
3670 #else
3671 return false;
3672 #endif
3673 }
3674
3675 // System loadavg support. Returns -1 if load average cannot be obtained.
3676 // Bsd doesn't yet have a (official) notion of processor sets,
3677 // so just return the system wide load average.
3678 int os::loadavg(double loadavg[], int nelem) {
3679 return ::getloadavg(loadavg, nelem);
3680 }
3681
3682 void os::pause() {
3683 char filename[MAX_PATH];
3684 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3685 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
3686 } else {
3687 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3688 }
3689
3690 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3691 if (fd != -1) {
3692 struct stat buf;
3693 ::close(fd);
3694 while (::stat(filename, &buf) == 0) {
3695 (void)::poll(NULL, 0, 100);
3696 }
3697 } else {
3698 jio_fprintf(stderr,
3699 "Could not open pause file '%s', continuing immediately.\n", filename);
3700 }
3701 }
3702
3703 // Darwin has no "environ" in a dynamic library.
3704 #ifdef __APPLE__
3705 #include <crt_externs.h>
3706 #define environ (*_NSGetEnviron())
3707 #else
3708 extern char** environ;
3709 #endif
3710
3711 // Run the specified command in a separate process. Return its exit value,
3712 // or -1 on failure (e.g. can't fork a new process).
3713 // Unlike system(), this function can be called from signal handler. It
3714 // doesn't block SIGINT et al.
3715 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3716 const char * argv[4] = {"sh", "-c", cmd, NULL};
3717
3718 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3719 // pthread_atfork handlers and reset pthread library. All we need is a
3720 // separate process to execve. Make a direct syscall to fork process.
3721 // On IA64 there's no fork syscall, we have to use fork() and hope for
3722 // the best...
3723 pid_t pid = fork();
3724
3725 if (pid < 0) {
3726 // fork failed
3727 return -1;
3728
3729 } else if (pid == 0) {
3730 // child process
3731
3732 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3733 // first to kill every thread on the thread list. Because this list is
3734 // not reset by fork() (see notes above), execve() will instead kill
3735 // every thread in the parent process. We know this is the only thread
3736 // in the new process, so make a system call directly.
3737 // IA64 should use normal execve() from glibc to match the glibc fork()
3738 // above.
3739 execve("/bin/sh", (char* const*)argv, environ);
3740
3741 // execve failed
3742 _exit(-1);
3743
3744 } else {
3745 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3746 // care about the actual exit code, for now.
3747
3748 int status;
3749
3750 // Wait for the child process to exit. This returns immediately if
3751 // the child has already exited. */
3752 while (waitpid(pid, &status, 0) < 0) {
3753 switch (errno) {
3754 case ECHILD: return 0;
3755 case EINTR: break;
3756 default: return -1;
3757 }
3758 }
3759
3760 if (WIFEXITED(status)) {
3761 // The child exited normally; get its exit code.
3762 return WEXITSTATUS(status);
3763 } else if (WIFSIGNALED(status)) {
3764 // The child exited because of a signal
3765 // The best value to return is 0x80 + signal number,
3766 // because that is what all Unix shells do, and because
3767 // it allows callers to distinguish between process exit and
3768 // process death by signal.
3769 return 0x80 + WTERMSIG(status);
3770 } else {
3771 // Unknown exit code; pass it through
3772 return status;
3773 }
3774 }
3775 }
3776
3777 // Get the default path to the core file
3778 // Returns the length of the string
3779 int os::get_core_path(char* buffer, size_t bufferSize) {
3780 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
3781
3782 // Truncate if theoretical string was longer than bufferSize
3783 n = MIN2(n, (int)bufferSize);
3784
3785 return n;
3786 }
3787
3788 bool os::supports_map_sync() {
3789 return false;
3790 }
3791
3792 #ifndef PRODUCT
3793 void TestReserveMemorySpecial_test() {
3794 // No tests available for this platform
3795 }
3796 #endif
3797
3798 bool os::start_debugging(char *buf, int buflen) {
3799 int len = (int)strlen(buf);
3800 char *p = &buf[len];
3801
3802 jio_snprintf(p, buflen-len,
3803 "\n\n"
3804 "Do you want to debug the problem?\n\n"
3805 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3806 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3807 "Otherwise, press RETURN to abort...",
3808 os::current_process_id(), os::current_process_id(),
3809 os::current_thread_id(), os::current_thread_id());
3810
3811 bool yes = os::message_box("Unexpected Error", buf);
3812
3813 if (yes) {
3814 // yes, user asked VM to launch debugger
3815 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3816 os::current_process_id(), os::current_process_id());
3817
3818 os::fork_and_exec(buf);
3819 yes = false;
3820 }
3821 return yes;
3822 }