1 /*
2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "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 "memory/allocation.inline.hpp"
37 #include "memory/filemap.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_bsd.inline.hpp"
40 #include "os_share_bsd.hpp"
41 #include "prims/jniFastGetField.hpp"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/atomic.hpp"
45 #include "runtime/extendedPC.hpp"
46 #include "runtime/globals.hpp"
47 #include "runtime/interfaceSupport.inline.hpp"
48 #include "runtime/java.hpp"
49 #include "runtime/javaCalls.hpp"
50 #include "runtime/mutexLocker.hpp"
51 #include "runtime/objectMonitor.hpp"
52 #include "runtime/orderAccess.hpp"
53 #include "runtime/osThread.hpp"
54 #include "runtime/perfMemory.hpp"
55 #include "runtime/semaphore.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/statSampler.hpp"
58 #include "runtime/stubRoutines.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "runtime/threadCritical.hpp"
61 #include "runtime/timer.hpp"
62 #include "services/attachListener.hpp"
63 #include "services/memTracker.hpp"
64 #include "services/runtimeService.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/decoder.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69 #include "utilities/growableArray.hpp"
70 #include "utilities/vmError.hpp"
71
72 // put OS-includes here
73 # include <sys/types.h>
74 # include <sys/mman.h>
75 # include <sys/stat.h>
76 # include <sys/select.h>
77 # include <pthread.h>
78 # include <signal.h>
79 # include <errno.h>
80 # include <dlfcn.h>
81 # include <stdio.h>
82 # include <unistd.h>
83 # include <sys/resource.h>
84 # include <pthread.h>
85 # include <sys/stat.h>
86 # include <sys/time.h>
87 # include <sys/times.h>
88 # include <sys/utsname.h>
89 # include <sys/socket.h>
90 # include <sys/wait.h>
91 # include <time.h>
92 # include <pwd.h>
93 # include <poll.h>
94 # include <fcntl.h>
95 # include <string.h>
96 # include <sys/param.h>
97 # include <sys/sysctl.h>
98 # include <sys/ipc.h>
99 # include <sys/shm.h>
100 #ifndef __APPLE__
101 # include <link.h>
102 #endif
103 # include <stdint.h>
104 # include <inttypes.h>
105 # include <sys/ioctl.h>
106 # include <sys/syscall.h>
107
108 #if defined(__FreeBSD__) || defined(__NetBSD__)
109 #include <elf.h>
110 #endif
111
112 #ifdef __APPLE__
113 #include <mach/mach.h> // semaphore_* API
114 #include <mach-o/dyld.h>
115 #include <sys/proc_info.h>
116 #include <objc/objc-auto.h>
117 #endif
118
119 #ifndef MAP_ANONYMOUS
120 #define MAP_ANONYMOUS MAP_ANON
121 #endif
122
123 #define MAX_PATH (2 * K)
124
125 // for timer info max values which include all bits
126 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
127
128 #define LARGEPAGES_BIT (1 << 6)
129
130 ////////////////////////////////////////////////////////////////////////////////
131 // global variables
132 julong os::Bsd::_physical_memory = 0;
133
134 #ifdef __APPLE__
135 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
136 volatile uint64_t os::Bsd::_max_abstime = 0;
137 #else
138 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
139 #endif
140 pthread_t os::Bsd::_main_thread;
141 int os::Bsd::_page_size = -1;
142
143 static jlong initial_time_count=0;
144
145 static int clock_tics_per_sec = 100;
146
147 // For diagnostics to print a message once. see run_periodic_checks
148 static sigset_t check_signal_done;
149 static bool check_signals = true;
150
151 static pid_t _initial_pid = 0;
152
153 // Signal number used to suspend/resume a thread
154
155 // do not use any signal number less than SIGSEGV, see 4355769
156 static int SR_signum = SIGUSR2;
157 sigset_t SR_sigset;
158
159
160 ////////////////////////////////////////////////////////////////////////////////
161 // utility functions
162
163 static int SR_initialize();
164
165 julong os::available_memory() {
166 return Bsd::available_memory();
167 }
168
169 // available here means free
170 julong os::Bsd::available_memory() {
171 uint64_t available = physical_memory() >> 2;
172 #ifdef __APPLE__
173 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
174 vm_statistics64_data_t vmstat;
175 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
176 (host_info64_t)&vmstat, &count);
177 assert(kerr == KERN_SUCCESS,
178 "host_statistics64 failed - check mach_host_self() and count");
179 if (kerr == KERN_SUCCESS) {
180 available = vmstat.free_count * os::vm_page_size();
181 }
182 #endif
183 return available;
184 }
185
186 julong os::physical_memory() {
187 return Bsd::physical_memory();
188 }
189
190 // Return true if user is running as root.
191
192 bool os::have_special_privileges() {
193 static bool init = false;
194 static bool privileges = false;
195 if (!init) {
196 privileges = (getuid() != geteuid()) || (getgid() != getegid());
197 init = true;
198 }
199 return privileges;
200 }
201
202
203
204 // Cpu architecture string
205 #if defined(ZERO)
206 static char cpu_arch[] = ZERO_LIBARCH;
207 #elif defined(IA64)
208 static char cpu_arch[] = "ia64";
209 #elif defined(IA32)
210 static char cpu_arch[] = "i386";
211 #elif defined(AMD64)
212 static char cpu_arch[] = "amd64";
213 #elif defined(ARM)
214 static char cpu_arch[] = "arm";
215 #elif defined(PPC32)
216 static char cpu_arch[] = "ppc";
217 #elif defined(SPARC)
218 #ifdef _LP64
219 static char cpu_arch[] = "sparcv9";
220 #else
221 static char cpu_arch[] = "sparc";
222 #endif
223 #else
224 #error Add appropriate cpu_arch setting
225 #endif
226
227 // Compiler variant
228 #ifdef COMPILER2
229 #define COMPILER_VARIANT "server"
230 #else
231 #define COMPILER_VARIANT "client"
232 #endif
233
234
235 void os::Bsd::initialize_system_info() {
236 int mib[2];
237 size_t len;
238 int cpu_val;
239 julong mem_val;
240
241 // get processors count via hw.ncpus sysctl
242 mib[0] = CTL_HW;
243 mib[1] = HW_NCPU;
244 len = sizeof(cpu_val);
245 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
246 assert(len == sizeof(cpu_val), "unexpected data size");
247 set_processor_count(cpu_val);
248 } else {
249 set_processor_count(1); // fallback
250 }
251
252 // get physical memory via hw.memsize sysctl (hw.memsize is used
253 // since it returns a 64 bit value)
254 mib[0] = CTL_HW;
255
256 #if defined (HW_MEMSIZE) // Apple
257 mib[1] = HW_MEMSIZE;
258 #elif defined(HW_PHYSMEM) // Most of BSD
259 mib[1] = HW_PHYSMEM;
260 #elif defined(HW_REALMEM) // Old FreeBSD
261 mib[1] = HW_REALMEM;
262 #else
263 #error No ways to get physmem
264 #endif
265
266 len = sizeof(mem_val);
267 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
268 assert(len == sizeof(mem_val), "unexpected data size");
269 _physical_memory = mem_val;
270 } else {
271 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
272 }
273
274 #ifdef __OpenBSD__
275 {
276 // limit _physical_memory memory view on OpenBSD since
277 // datasize rlimit restricts us anyway.
278 struct rlimit limits;
279 getrlimit(RLIMIT_DATA, &limits);
280 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
281 }
282 #endif
283 }
284
285 #ifdef __APPLE__
286 static const char *get_home() {
287 const char *home_dir = ::getenv("HOME");
288 if ((home_dir == NULL) || (*home_dir == '\0')) {
289 struct passwd *passwd_info = getpwuid(geteuid());
290 if (passwd_info != NULL) {
291 home_dir = passwd_info->pw_dir;
292 }
293 }
294
295 return home_dir;
296 }
297 #endif
298
299 void os::init_system_properties_values() {
300 // The next steps are taken in the product version:
301 //
302 // Obtain the JAVA_HOME value from the location of libjvm.so.
303 // This library should be located at:
304 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
305 //
306 // If "/jre/lib/" appears at the right place in the path, then we
307 // assume libjvm.so is installed in a JDK and we use this path.
308 //
309 // Otherwise exit with message: "Could not create the Java virtual machine."
310 //
311 // The following extra steps are taken in the debugging version:
312 //
313 // If "/jre/lib/" does NOT appear at the right place in the path
314 // instead of exit check for $JAVA_HOME environment variable.
315 //
316 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
317 // then we append a fake suffix "hotspot/libjvm.so" to this path so
318 // it looks like libjvm.so is installed there
319 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
320 //
321 // Otherwise exit.
322 //
323 // Important note: if the location of libjvm.so changes this
324 // code needs to be changed accordingly.
325
326 // See ld(1):
327 // The linker uses the following search paths to locate required
328 // shared libraries:
329 // 1: ...
330 // ...
331 // 7: The default directories, normally /lib and /usr/lib.
332 #ifndef DEFAULT_LIBPATH
333 #define DEFAULT_LIBPATH "/lib:/usr/lib"
334 #endif
335
336 // Base path of extensions installed on the system.
337 #define SYS_EXT_DIR "/usr/java/packages"
338 #define EXTENSIONS_DIR "/lib/ext"
339
340 #ifndef __APPLE__
341
342 // Buffer that fits several sprintfs.
343 // Note that the space for the colon and the trailing null are provided
344 // by the nulls included by the sizeof operator.
345 const size_t bufsize =
346 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
347 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
348 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
349
350 // sysclasspath, java_home, dll_dir
351 {
352 char *pslash;
353 os::jvm_path(buf, bufsize);
354
355 // Found the full path to libjvm.so.
356 // Now cut the path to <java_home>/jre if we can.
357 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
358 pslash = strrchr(buf, '/');
359 if (pslash != NULL) {
360 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
361 }
362 Arguments::set_dll_dir(buf);
363
364 if (pslash != NULL) {
365 pslash = strrchr(buf, '/');
366 if (pslash != NULL) {
367 *pslash = '\0'; // Get rid of /<arch>.
368 pslash = strrchr(buf, '/');
369 if (pslash != NULL) {
370 *pslash = '\0'; // Get rid of /lib.
371 }
372 }
373 }
374 Arguments::set_java_home(buf);
375 set_boot_path('/', ':');
376 }
377
378 // Where to look for native libraries.
379 //
380 // Note: Due to a legacy implementation, most of the library path
381 // is set in the launcher. This was to accomodate linking restrictions
382 // on legacy Bsd implementations (which are no longer supported).
383 // Eventually, all the library path setting will be done here.
384 //
385 // However, to prevent the proliferation of improperly built native
386 // libraries, the new path component /usr/java/packages is added here.
387 // Eventually, all the library path setting will be done here.
388 {
389 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
390 // should always exist (until the legacy problem cited above is
391 // addressed).
392 const char *v = ::getenv("LD_LIBRARY_PATH");
393 const char *v_colon = ":";
394 if (v == NULL) { v = ""; v_colon = ""; }
395 // That's +1 for the colon and +1 for the trailing '\0'.
396 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
397 strlen(v) + 1 +
398 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
399 mtInternal);
400 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
401 Arguments::set_library_path(ld_library_path);
402 FREE_C_HEAP_ARRAY(char, ld_library_path);
403 }
404
405 // Extensions directories.
406 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
407 Arguments::set_ext_dirs(buf);
408
409 FREE_C_HEAP_ARRAY(char, buf);
410
411 #else // __APPLE__
412
413 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
414 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
415
416 const char *user_home_dir = get_home();
417 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
418 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
419 sizeof(SYS_EXTENSIONS_DIRS);
420
421 // Buffer that fits several sprintfs.
422 // Note that the space for the colon and the trailing null are provided
423 // by the nulls included by the sizeof operator.
424 const size_t bufsize =
425 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
426 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
427 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
428
429 // sysclasspath, java_home, dll_dir
430 {
431 char *pslash;
432 os::jvm_path(buf, bufsize);
433
434 // Found the full path to libjvm.so.
435 // Now cut the path to <java_home>/jre if we can.
436 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
437 pslash = strrchr(buf, '/');
438 if (pslash != NULL) {
439 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
440 }
441 #ifdef STATIC_BUILD
442 strcat(buf, "/lib");
443 #endif
444
445 Arguments::set_dll_dir(buf);
446
447 if (pslash != NULL) {
448 pslash = strrchr(buf, '/');
449 if (pslash != NULL) {
450 *pslash = '\0'; // Get rid of /lib.
451 }
452 }
453 Arguments::set_java_home(buf);
454 set_boot_path('/', ':');
455 }
456
457 // Where to look for native libraries.
458 //
459 // Note: Due to a legacy implementation, most of the library path
460 // is set in the launcher. This was to accomodate linking restrictions
461 // on legacy Bsd implementations (which are no longer supported).
462 // Eventually, all the library path setting will be done here.
463 //
464 // However, to prevent the proliferation of improperly built native
465 // libraries, the new path component /usr/java/packages is added here.
466 // Eventually, all the library path setting will be done here.
467 {
468 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
469 // should always exist (until the legacy problem cited above is
470 // addressed).
471 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
472 // can specify a directory inside an app wrapper
473 const char *l = ::getenv("JAVA_LIBRARY_PATH");
474 const char *l_colon = ":";
475 if (l == NULL) { l = ""; l_colon = ""; }
476
477 const char *v = ::getenv("DYLD_LIBRARY_PATH");
478 const char *v_colon = ":";
479 if (v == NULL) { v = ""; v_colon = ""; }
480
481 // Apple's Java6 has "." at the beginning of java.library.path.
482 // OpenJDK on Windows has "." at the end of java.library.path.
483 // OpenJDK on Linux and Solaris don't have "." in java.library.path
484 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
485 // "." is appended to the end of java.library.path. Yes, this
486 // could cause a change in behavior, but Apple's Java6 behavior
487 // can be achieved by putting "." at the beginning of the
488 // JAVA_LIBRARY_PATH environment variable.
489 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
490 strlen(v) + 1 + strlen(l) + 1 +
491 system_ext_size + 3,
492 mtInternal);
493 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
494 v, v_colon, l, l_colon, user_home_dir);
495 Arguments::set_library_path(ld_library_path);
496 FREE_C_HEAP_ARRAY(char, ld_library_path);
497 }
498
499 // Extensions directories.
500 //
501 // Note that the space for the colon and the trailing null are provided
502 // by the nulls included by the sizeof operator (so actually one byte more
503 // than necessary is allocated).
504 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
505 user_home_dir, Arguments::get_java_home());
506 Arguments::set_ext_dirs(buf);
507
508 FREE_C_HEAP_ARRAY(char, buf);
509
510 #undef SYS_EXTENSIONS_DIR
511 #undef SYS_EXTENSIONS_DIRS
512
513 #endif // __APPLE__
514
515 #undef SYS_EXT_DIR
516 #undef EXTENSIONS_DIR
517 }
518
519 ////////////////////////////////////////////////////////////////////////////////
520 // breakpoint support
521
522 void os::breakpoint() {
523 BREAKPOINT;
524 }
525
526 extern "C" void breakpoint() {
527 // use debugger to set breakpoint here
528 }
529
530 ////////////////////////////////////////////////////////////////////////////////
531 // signal support
532
533 debug_only(static bool signal_sets_initialized = false);
534 static sigset_t unblocked_sigs, vm_sigs;
535
536 void os::Bsd::signal_sets_init() {
537 // Should also have an assertion stating we are still single-threaded.
538 assert(!signal_sets_initialized, "Already initialized");
539 // Fill in signals that are necessarily unblocked for all threads in
540 // the VM. Currently, we unblock the following signals:
541 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
542 // by -Xrs (=ReduceSignalUsage));
543 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
544 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
545 // the dispositions or masks wrt these signals.
546 // Programs embedding the VM that want to use the above signals for their
547 // own purposes must, at this time, use the "-Xrs" option to prevent
548 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
549 // (See bug 4345157, and other related bugs).
550 // In reality, though, unblocking these signals is really a nop, since
551 // these signals are not blocked by default.
552 sigemptyset(&unblocked_sigs);
553 sigaddset(&unblocked_sigs, SIGILL);
554 sigaddset(&unblocked_sigs, SIGSEGV);
555 sigaddset(&unblocked_sigs, SIGBUS);
556 sigaddset(&unblocked_sigs, SIGFPE);
557 sigaddset(&unblocked_sigs, SR_signum);
558
559 if (!ReduceSignalUsage) {
560 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
561 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
562
563 }
564 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
565 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
566 }
567 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
568 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
569 }
570 }
571 // Fill in signals that are blocked by all but the VM thread.
572 sigemptyset(&vm_sigs);
573 if (!ReduceSignalUsage) {
574 sigaddset(&vm_sigs, BREAK_SIGNAL);
575 }
576 debug_only(signal_sets_initialized = true);
577
578 }
579
580 // These are signals that are unblocked while a thread is running Java.
581 // (For some reason, they get blocked by default.)
582 sigset_t* os::Bsd::unblocked_signals() {
583 assert(signal_sets_initialized, "Not initialized");
584 return &unblocked_sigs;
585 }
586
587 // These are the signals that are blocked while a (non-VM) thread is
588 // running Java. Only the VM thread handles these signals.
589 sigset_t* os::Bsd::vm_signals() {
590 assert(signal_sets_initialized, "Not initialized");
591 return &vm_sigs;
592 }
593
594 void os::Bsd::hotspot_sigmask(Thread* thread) {
595
596 //Save caller's signal mask before setting VM signal mask
597 sigset_t caller_sigmask;
598 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
599
600 OSThread* osthread = thread->osthread();
601 osthread->set_caller_sigmask(caller_sigmask);
602
603 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
604
605 if (!ReduceSignalUsage) {
606 if (thread->is_VM_thread()) {
607 // Only the VM thread handles BREAK_SIGNAL ...
608 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
609 } else {
610 // ... all other threads block BREAK_SIGNAL
611 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
612 }
613 }
614 }
615
616
617 //////////////////////////////////////////////////////////////////////////////
618 // create new thread
619
620 #ifdef __APPLE__
621 // library handle for calling objc_registerThreadWithCollector()
622 // without static linking to the libobjc library
623 #define OBJC_LIB "/usr/lib/libobjc.dylib"
624 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
625 typedef void (*objc_registerThreadWithCollector_t)();
626 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
627 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
628 #endif
629
630 #ifdef __APPLE__
631 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
632 // Additional thread_id used to correlate threads in SA
633 thread_identifier_info_data_t m_ident_info;
634 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
635
636 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
637 (thread_info_t) &m_ident_info, &count);
638
639 return m_ident_info.thread_id;
640 }
641 #endif
642
643 // Thread start routine for all newly created threads
644 static void *thread_native_entry(Thread *thread) {
645 // Try to randomize the cache line index of hot stack frames.
646 // This helps when threads of the same stack traces evict each other's
647 // cache lines. The threads can be either from the same JVM instance, or
648 // from different JVM instances. The benefit is especially true for
649 // processors with hyperthreading technology.
650 static int counter = 0;
651 int pid = os::current_process_id();
652 alloca(((pid ^ counter++) & 7) * 128);
653
654 thread->initialize_thread_current();
655
656 OSThread* osthread = thread->osthread();
657 Monitor* sync = osthread->startThread_lock();
658
659 osthread->set_thread_id(os::Bsd::gettid());
660
661 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
662 os::current_thread_id(), (uintx) pthread_self());
663
664 #ifdef __APPLE__
665 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
666 guarantee(unique_thread_id != 0, "unique thread id was not found");
667 osthread->set_unique_thread_id(unique_thread_id);
668 #endif
669 // initialize signal mask for this thread
670 os::Bsd::hotspot_sigmask(thread);
671
672 // initialize floating point control register
673 os::Bsd::init_thread_fpu_state();
674
675 #ifdef __APPLE__
676 // register thread with objc gc
677 if (objc_registerThreadWithCollectorFunction != NULL) {
678 objc_registerThreadWithCollectorFunction();
679 }
680 #endif
681
682 // handshaking with parent thread
683 {
684 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
685
686 // notify parent thread
687 osthread->set_state(INITIALIZED);
688 sync->notify_all();
689
690 // wait until os::start_thread()
691 while (osthread->get_state() == INITIALIZED) {
692 sync->wait(Mutex::_no_safepoint_check_flag);
693 }
694 }
695
696 // call one more level start routine
697 thread->run();
698
699 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
700 os::current_thread_id(), (uintx) pthread_self());
701
702 // If a thread has not deleted itself ("delete this") as part of its
703 // termination sequence, we have to ensure thread-local-storage is
704 // cleared before we actually terminate. No threads should ever be
705 // deleted asynchronously with respect to their termination.
706 if (Thread::current_or_null_safe() != NULL) {
707 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
708 thread->clear_thread_current();
709 }
710
711 return 0;
712 }
713
714 bool os::create_thread(Thread* thread, ThreadType thr_type,
715 size_t req_stack_size) {
716 assert(thread->osthread() == NULL, "caller responsible");
717
718 // Allocate the OSThread object
719 OSThread* osthread = new OSThread(NULL, NULL);
720 if (osthread == NULL) {
721 return false;
722 }
723
724 // set the correct thread state
725 osthread->set_thread_type(thr_type);
726
727 // Initial state is ALLOCATED but not INITIALIZED
728 osthread->set_state(ALLOCATED);
729
730 thread->set_osthread(osthread);
731
732 // init thread attributes
733 pthread_attr_t attr;
734 pthread_attr_init(&attr);
735 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
736
737 // calculate stack size if it's not specified by caller
738 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
739 int status = pthread_attr_setstacksize(&attr, stack_size);
740 assert_status(status == 0, status, "pthread_attr_setstacksize");
741
742 ThreadState state;
743
744 {
745 pthread_t tid;
746 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
747
748 char buf[64];
749 if (ret == 0) {
750 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
751 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
752 } else {
753 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
754 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
755 }
756
757 pthread_attr_destroy(&attr);
758
759 if (ret != 0) {
760 // Need to clean up stuff we've allocated so far
761 thread->set_osthread(NULL);
762 delete osthread;
763 return false;
764 }
765
766 // Store pthread info into the OSThread
767 osthread->set_pthread_id(tid);
768
769 // Wait until child thread is either initialized or aborted
770 {
771 Monitor* sync_with_child = osthread->startThread_lock();
772 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
773 while ((state = osthread->get_state()) == ALLOCATED) {
774 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
775 }
776 }
777
778 }
779
780 // Aborted due to thread limit being reached
781 if (state == ZOMBIE) {
782 thread->set_osthread(NULL);
783 delete osthread;
784 return false;
785 }
786
787 // The thread is returned suspended (in state INITIALIZED),
788 // and is started higher up in the call chain
789 assert(state == INITIALIZED, "race condition");
790 return true;
791 }
792
793 /////////////////////////////////////////////////////////////////////////////
794 // attach existing thread
795
796 // bootstrap the main thread
797 bool os::create_main_thread(JavaThread* thread) {
798 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
799 return create_attached_thread(thread);
800 }
801
802 bool os::create_attached_thread(JavaThread* thread) {
803 #ifdef ASSERT
804 thread->verify_not_published();
805 #endif
806
807 // Allocate the OSThread object
808 OSThread* osthread = new OSThread(NULL, NULL);
809
810 if (osthread == NULL) {
811 return false;
812 }
813
814 osthread->set_thread_id(os::Bsd::gettid());
815
816 // Store pthread info into the OSThread
817 #ifdef __APPLE__
818 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
819 guarantee(unique_thread_id != 0, "just checking");
820 osthread->set_unique_thread_id(unique_thread_id);
821 #endif
822 osthread->set_pthread_id(::pthread_self());
823
824 // initialize floating point control register
825 os::Bsd::init_thread_fpu_state();
826
827 // Initial thread state is RUNNABLE
828 osthread->set_state(RUNNABLE);
829
830 thread->set_osthread(osthread);
831
832 // initialize signal mask for this thread
833 // and save the caller's signal mask
834 os::Bsd::hotspot_sigmask(thread);
835
836 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
837 os::current_thread_id(), (uintx) pthread_self());
838
839 return true;
840 }
841
842 void os::pd_start_thread(Thread* thread) {
843 OSThread * osthread = thread->osthread();
844 assert(osthread->get_state() != INITIALIZED, "just checking");
845 Monitor* sync_with_child = osthread->startThread_lock();
846 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
847 sync_with_child->notify();
848 }
849
850 // Free Bsd resources related to the OSThread
851 void os::free_thread(OSThread* osthread) {
852 assert(osthread != NULL, "osthread not set");
853
854 // We are told to free resources of the argument thread,
855 // but we can only really operate on the current thread.
856 assert(Thread::current()->osthread() == osthread,
857 "os::free_thread but not current thread");
858
859 // Restore caller's signal mask
860 sigset_t sigmask = osthread->caller_sigmask();
861 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
862
863 delete osthread;
864 }
865
866 ////////////////////////////////////////////////////////////////////////////////
867 // time support
868
869 // Time since start-up in seconds to a fine granularity.
870 // Used by VMSelfDestructTimer and the MemProfiler.
871 double os::elapsedTime() {
872
873 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
874 }
875
876 jlong os::elapsed_counter() {
877 return javaTimeNanos() - initial_time_count;
878 }
879
880 jlong os::elapsed_frequency() {
881 return NANOSECS_PER_SEC; // nanosecond resolution
882 }
883
884 bool os::supports_vtime() { return true; }
885 bool os::enable_vtime() { return false; }
886 bool os::vtime_enabled() { return false; }
887
888 double os::elapsedVTime() {
889 // better than nothing, but not much
890 return elapsedTime();
891 }
892
893 jlong os::javaTimeMillis() {
894 timeval time;
895 int status = gettimeofday(&time, NULL);
896 assert(status != -1, "bsd error");
897 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
898 }
899
900 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
901 timeval time;
902 int status = gettimeofday(&time, NULL);
903 assert(status != -1, "bsd error");
904 seconds = jlong(time.tv_sec);
905 nanos = jlong(time.tv_usec) * 1000;
906 }
907
908 #ifndef __APPLE__
909 #ifndef CLOCK_MONOTONIC
910 #define CLOCK_MONOTONIC (1)
911 #endif
912 #endif
913
914 #ifdef __APPLE__
915 void os::Bsd::clock_init() {
916 mach_timebase_info(&_timebase_info);
917 }
918 #else
919 void os::Bsd::clock_init() {
920 struct timespec res;
921 struct timespec tp;
922 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
923 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
924 // yes, monotonic clock is supported
925 _clock_gettime = ::clock_gettime;
926 }
927 }
928 #endif
929
930
931
932 #ifdef __APPLE__
933
934 jlong os::javaTimeNanos() {
935 const uint64_t tm = mach_absolute_time();
936 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
937 const uint64_t prev = Bsd::_max_abstime;
938 if (now <= prev) {
939 return prev; // same or retrograde time;
940 }
941 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev);
942 assert(obsv >= prev, "invariant"); // Monotonicity
943 // If the CAS succeeded then we're done and return "now".
944 // If the CAS failed and the observed value "obsv" is >= now then
945 // we should return "obsv". If the CAS failed and now > obsv > prv then
946 // some other thread raced this thread and installed a new value, in which case
947 // we could either (a) retry the entire operation, (b) retry trying to install now
948 // or (c) just return obsv. We use (c). No loop is required although in some cases
949 // we might discard a higher "now" value in deference to a slightly lower but freshly
950 // installed obsv value. That's entirely benign -- it admits no new orderings compared
951 // to (a) or (b) -- and greatly reduces coherence traffic.
952 // We might also condition (c) on the magnitude of the delta between obsv and now.
953 // Avoiding excessive CAS operations to hot RW locations is critical.
954 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
955 return (prev == obsv) ? now : obsv;
956 }
957
958 #else // __APPLE__
959
960 jlong os::javaTimeNanos() {
961 if (os::supports_monotonic_clock()) {
962 struct timespec tp;
963 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
964 assert(status == 0, "gettime error");
965 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
966 return result;
967 } else {
968 timeval time;
969 int status = gettimeofday(&time, NULL);
970 assert(status != -1, "bsd error");
971 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
972 return 1000 * usecs;
973 }
974 }
975
976 #endif // __APPLE__
977
978 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
979 if (os::supports_monotonic_clock()) {
980 info_ptr->max_value = ALL_64_BITS;
981
982 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
983 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
984 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
985 } else {
986 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
987 info_ptr->max_value = ALL_64_BITS;
988
989 // gettimeofday is a real time clock so it skips
990 info_ptr->may_skip_backward = true;
991 info_ptr->may_skip_forward = true;
992 }
993
994 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
995 }
996
997 // Return the real, user, and system times in seconds from an
998 // arbitrary fixed point in the past.
999 bool os::getTimesSecs(double* process_real_time,
1000 double* process_user_time,
1001 double* process_system_time) {
1002 struct tms ticks;
1003 clock_t real_ticks = times(&ticks);
1004
1005 if (real_ticks == (clock_t) (-1)) {
1006 return false;
1007 } else {
1008 double ticks_per_second = (double) clock_tics_per_sec;
1009 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1010 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1011 *process_real_time = ((double) real_ticks) / ticks_per_second;
1012
1013 return true;
1014 }
1015 }
1016
1017
1018 char * os::local_time_string(char *buf, size_t buflen) {
1019 struct tm t;
1020 time_t long_time;
1021 time(&long_time);
1022 localtime_r(&long_time, &t);
1023 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1024 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1025 t.tm_hour, t.tm_min, t.tm_sec);
1026 return buf;
1027 }
1028
1029 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1030 return localtime_r(clock, res);
1031 }
1032
1033 ////////////////////////////////////////////////////////////////////////////////
1034 // runtime exit support
1035
1036 // Note: os::shutdown() might be called very early during initialization, or
1037 // called from signal handler. Before adding something to os::shutdown(), make
1038 // sure it is async-safe and can handle partially initialized VM.
1039 void os::shutdown() {
1040
1041 // allow PerfMemory to attempt cleanup of any persistent resources
1042 perfMemory_exit();
1043
1044 // needs to remove object in file system
1045 AttachListener::abort();
1046
1047 // flush buffered output, finish log files
1048 ostream_abort();
1049
1050 // Check for abort hook
1051 abort_hook_t abort_hook = Arguments::abort_hook();
1052 if (abort_hook != NULL) {
1053 abort_hook();
1054 }
1055
1056 }
1057
1058 // Note: os::abort() might be called very early during initialization, or
1059 // called from signal handler. Before adding something to os::abort(), make
1060 // sure it is async-safe and can handle partially initialized VM.
1061 void os::abort(bool dump_core, void* siginfo, const void* context) {
1062 os::shutdown();
1063 if (dump_core) {
1064 #ifndef PRODUCT
1065 fdStream out(defaultStream::output_fd());
1066 out.print_raw("Current thread is ");
1067 char buf[16];
1068 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1069 out.print_raw_cr(buf);
1070 out.print_raw_cr("Dumping core ...");
1071 #endif
1072 ::abort(); // dump core
1073 }
1074
1075 ::exit(1);
1076 }
1077
1078 // Die immediately, no exit hook, no abort hook, no cleanup.
1079 void os::die() {
1080 // _exit() on BsdThreads only kills current thread
1081 ::abort();
1082 }
1083
1084 // Information of current thread in variety of formats
1085 pid_t os::Bsd::gettid() {
1086 int retval = -1;
1087
1088 #ifdef __APPLE__ //XNU kernel
1089 // despite the fact mach port is actually not a thread id use it
1090 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1091 retval = ::pthread_mach_thread_np(::pthread_self());
1092 guarantee(retval != 0, "just checking");
1093 return retval;
1094
1095 #else
1096 #ifdef __FreeBSD__
1097 retval = syscall(SYS_thr_self);
1098 #else
1099 #ifdef __OpenBSD__
1100 retval = syscall(SYS_getthrid);
1101 #else
1102 #ifdef __NetBSD__
1103 retval = (pid_t) syscall(SYS__lwp_self);
1104 #endif
1105 #endif
1106 #endif
1107 #endif
1108
1109 if (retval == -1) {
1110 return getpid();
1111 }
1112 }
1113
1114 intx os::current_thread_id() {
1115 #ifdef __APPLE__
1116 return (intx)::pthread_mach_thread_np(::pthread_self());
1117 #else
1118 return (intx)::pthread_self();
1119 #endif
1120 }
1121
1122 int os::current_process_id() {
1123
1124 // Under the old bsd thread library, bsd gives each thread
1125 // its own process id. Because of this each thread will return
1126 // a different pid if this method were to return the result
1127 // of getpid(2). Bsd provides no api that returns the pid
1128 // of the launcher thread for the vm. This implementation
1129 // returns a unique pid, the pid of the launcher thread
1130 // that starts the vm 'process'.
1131
1132 // Under the NPTL, getpid() returns the same pid as the
1133 // launcher thread rather than a unique pid per thread.
1134 // Use gettid() if you want the old pre NPTL behaviour.
1135
1136 // if you are looking for the result of a call to getpid() that
1137 // returns a unique pid for the calling thread, then look at the
1138 // OSThread::thread_id() method in osThread_bsd.hpp file
1139
1140 return (int)(_initial_pid ? _initial_pid : getpid());
1141 }
1142
1143 // DLL functions
1144
1145 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1146
1147 // This must be hard coded because it's the system's temporary
1148 // directory not the java application's temp directory, ala java.io.tmpdir.
1149 #ifdef __APPLE__
1150 // macosx has a secure per-user temporary directory
1151 char temp_path_storage[PATH_MAX];
1152 const char* os::get_temp_directory() {
1153 static char *temp_path = NULL;
1154 if (temp_path == NULL) {
1155 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1156 if (pathSize == 0 || pathSize > PATH_MAX) {
1157 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1158 }
1159 temp_path = temp_path_storage;
1160 }
1161 return temp_path;
1162 }
1163 #else // __APPLE__
1164 const char* os::get_temp_directory() { return "/tmp"; }
1165 #endif // __APPLE__
1166
1167 // check if addr is inside libjvm.so
1168 bool os::address_is_in_vm(address addr) {
1169 static address libjvm_base_addr;
1170 Dl_info dlinfo;
1171
1172 if (libjvm_base_addr == NULL) {
1173 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1174 libjvm_base_addr = (address)dlinfo.dli_fbase;
1175 }
1176 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1177 }
1178
1179 if (dladdr((void *)addr, &dlinfo) != 0) {
1180 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1181 }
1182
1183 return false;
1184 }
1185
1186
1187 #define MACH_MAXSYMLEN 256
1188
1189 bool os::dll_address_to_function_name(address addr, char *buf,
1190 int buflen, int *offset,
1191 bool demangle) {
1192 // buf is not optional, but offset is optional
1193 assert(buf != NULL, "sanity check");
1194
1195 Dl_info dlinfo;
1196 char localbuf[MACH_MAXSYMLEN];
1197
1198 if (dladdr((void*)addr, &dlinfo) != 0) {
1199 // see if we have a matching symbol
1200 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1201 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1202 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1203 }
1204 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1205 return true;
1206 }
1207 // no matching symbol so try for just file info
1208 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1209 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1210 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1211 return true;
1212 }
1213 }
1214
1215 // Handle non-dynamic manually:
1216 if (dlinfo.dli_fbase != NULL &&
1217 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1218 dlinfo.dli_fbase)) {
1219 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1220 jio_snprintf(buf, buflen, "%s", localbuf);
1221 }
1222 return true;
1223 }
1224 }
1225 buf[0] = '\0';
1226 if (offset != NULL) *offset = -1;
1227 return false;
1228 }
1229
1230 // ported from solaris version
1231 bool os::dll_address_to_library_name(address addr, char* buf,
1232 int buflen, int* offset) {
1233 // buf is not optional, but offset is optional
1234 assert(buf != NULL, "sanity check");
1235
1236 Dl_info dlinfo;
1237
1238 if (dladdr((void*)addr, &dlinfo) != 0) {
1239 if (dlinfo.dli_fname != NULL) {
1240 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1241 }
1242 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1243 *offset = addr - (address)dlinfo.dli_fbase;
1244 }
1245 return true;
1246 }
1247
1248 buf[0] = '\0';
1249 if (offset) *offset = -1;
1250 return false;
1251 }
1252
1253 // Loads .dll/.so and
1254 // in case of error it checks if .dll/.so was built for the
1255 // same architecture as Hotspot is running on
1256
1257 #ifdef __APPLE__
1258 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1259 #ifdef STATIC_BUILD
1260 return os::get_default_process_handle();
1261 #else
1262 void * result= ::dlopen(filename, RTLD_LAZY);
1263 if (result != NULL) {
1264 // Successful loading
1265 return result;
1266 }
1267
1268 // Read system error message into ebuf
1269 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1270 ebuf[ebuflen-1]='\0';
1271
1272 return NULL;
1273 #endif // STATIC_BUILD
1274 }
1275 #else
1276 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1277 #ifdef STATIC_BUILD
1278 return os::get_default_process_handle();
1279 #else
1280 void * result= ::dlopen(filename, RTLD_LAZY);
1281 if (result != NULL) {
1282 // Successful loading
1283 return result;
1284 }
1285
1286 Elf32_Ehdr elf_head;
1287
1288 // Read system error message into ebuf
1289 // It may or may not be overwritten below
1290 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1291 ebuf[ebuflen-1]='\0';
1292 int diag_msg_max_length=ebuflen-strlen(ebuf);
1293 char* diag_msg_buf=ebuf+strlen(ebuf);
1294
1295 if (diag_msg_max_length==0) {
1296 // No more space in ebuf for additional diagnostics message
1297 return NULL;
1298 }
1299
1300
1301 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1302
1303 if (file_descriptor < 0) {
1304 // Can't open library, report dlerror() message
1305 return NULL;
1306 }
1307
1308 bool failed_to_read_elf_head=
1309 (sizeof(elf_head)!=
1310 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1311
1312 ::close(file_descriptor);
1313 if (failed_to_read_elf_head) {
1314 // file i/o error - report dlerror() msg
1315 return NULL;
1316 }
1317
1318 typedef struct {
1319 Elf32_Half code; // Actual value as defined in elf.h
1320 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1321 char elf_class; // 32 or 64 bit
1322 char endianess; // MSB or LSB
1323 char* name; // String representation
1324 } arch_t;
1325
1326 #ifndef EM_486
1327 #define EM_486 6 /* Intel 80486 */
1328 #endif
1329
1330 #ifndef EM_MIPS_RS3_LE
1331 #define EM_MIPS_RS3_LE 10 /* MIPS */
1332 #endif
1333
1334 #ifndef EM_PPC64
1335 #define EM_PPC64 21 /* PowerPC64 */
1336 #endif
1337
1338 #ifndef EM_S390
1339 #define EM_S390 22 /* IBM System/390 */
1340 #endif
1341
1342 #ifndef EM_IA_64
1343 #define EM_IA_64 50 /* HP/Intel IA-64 */
1344 #endif
1345
1346 #ifndef EM_X86_64
1347 #define EM_X86_64 62 /* AMD x86-64 */
1348 #endif
1349
1350 static const arch_t arch_array[]={
1351 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1352 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1353 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1354 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1355 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1356 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1357 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1358 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1359 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1360 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1361 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1362 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1363 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1364 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1365 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1366 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1367 };
1368
1369 #if (defined IA32)
1370 static Elf32_Half running_arch_code=EM_386;
1371 #elif (defined AMD64)
1372 static Elf32_Half running_arch_code=EM_X86_64;
1373 #elif (defined IA64)
1374 static Elf32_Half running_arch_code=EM_IA_64;
1375 #elif (defined __sparc) && (defined _LP64)
1376 static Elf32_Half running_arch_code=EM_SPARCV9;
1377 #elif (defined __sparc) && (!defined _LP64)
1378 static Elf32_Half running_arch_code=EM_SPARC;
1379 #elif (defined __powerpc64__)
1380 static Elf32_Half running_arch_code=EM_PPC64;
1381 #elif (defined __powerpc__)
1382 static Elf32_Half running_arch_code=EM_PPC;
1383 #elif (defined ARM)
1384 static Elf32_Half running_arch_code=EM_ARM;
1385 #elif (defined S390)
1386 static Elf32_Half running_arch_code=EM_S390;
1387 #elif (defined ALPHA)
1388 static Elf32_Half running_arch_code=EM_ALPHA;
1389 #elif (defined MIPSEL)
1390 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1391 #elif (defined PARISC)
1392 static Elf32_Half running_arch_code=EM_PARISC;
1393 #elif (defined MIPS)
1394 static Elf32_Half running_arch_code=EM_MIPS;
1395 #elif (defined M68K)
1396 static Elf32_Half running_arch_code=EM_68K;
1397 #else
1398 #error Method os::dll_load requires that one of following is defined:\
1399 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1400 #endif
1401
1402 // Identify compatability class for VM's architecture and library's architecture
1403 // Obtain string descriptions for architectures
1404
1405 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1406 int running_arch_index=-1;
1407
1408 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1409 if (running_arch_code == arch_array[i].code) {
1410 running_arch_index = i;
1411 }
1412 if (lib_arch.code == arch_array[i].code) {
1413 lib_arch.compat_class = arch_array[i].compat_class;
1414 lib_arch.name = arch_array[i].name;
1415 }
1416 }
1417
1418 assert(running_arch_index != -1,
1419 "Didn't find running architecture code (running_arch_code) in arch_array");
1420 if (running_arch_index == -1) {
1421 // Even though running architecture detection failed
1422 // we may still continue with reporting dlerror() message
1423 return NULL;
1424 }
1425
1426 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1427 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1428 return NULL;
1429 }
1430
1431 #ifndef S390
1432 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1433 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1434 return NULL;
1435 }
1436 #endif // !S390
1437
1438 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1439 if (lib_arch.name!=NULL) {
1440 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1441 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1442 lib_arch.name, arch_array[running_arch_index].name);
1443 } else {
1444 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1445 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1446 lib_arch.code,
1447 arch_array[running_arch_index].name);
1448 }
1449 }
1450
1451 return NULL;
1452 #endif // STATIC_BUILD
1453 }
1454 #endif // !__APPLE__
1455
1456 void* os::get_default_process_handle() {
1457 #ifdef __APPLE__
1458 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1459 // to avoid finding unexpected symbols on second (or later)
1460 // loads of a library.
1461 return (void*)::dlopen(NULL, RTLD_FIRST);
1462 #else
1463 return (void*)::dlopen(NULL, RTLD_LAZY);
1464 #endif
1465 }
1466
1467 // XXX: Do we need a lock around this as per Linux?
1468 void* os::dll_lookup(void* handle, const char* name) {
1469 return dlsym(handle, name);
1470 }
1471
1472 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1473 outputStream * out = (outputStream *) param;
1474 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1475 return 0;
1476 }
1477
1478 void os::print_dll_info(outputStream *st) {
1479 st->print_cr("Dynamic libraries:");
1480 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1481 st->print_cr("Error: Cannot print dynamic libraries.");
1482 }
1483 }
1484
1485 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1486 #ifdef RTLD_DI_LINKMAP
1487 Dl_info dli;
1488 void *handle;
1489 Link_map *map;
1490 Link_map *p;
1491
1492 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1493 dli.dli_fname == NULL) {
1494 return 1;
1495 }
1496 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1497 if (handle == NULL) {
1498 return 1;
1499 }
1500 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1501 if (map == NULL) {
1502 dlclose(handle);
1503 return 1;
1504 }
1505
1506 while (map->l_prev != NULL)
1507 map = map->l_prev;
1508
1509 while (map != NULL) {
1510 // Value for top_address is returned as 0 since we don't have any information about module size
1511 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1512 dlclose(handle);
1513 return 1;
1514 }
1515 map = map->l_next;
1516 }
1517
1518 dlclose(handle);
1519 #elif defined(__APPLE__)
1520 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1521 // Value for top_address is returned as 0 since we don't have any information about module size
1522 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1523 return 1;
1524 }
1525 }
1526 return 0;
1527 #else
1528 return 1;
1529 #endif
1530 }
1531
1532 void os::get_summary_os_info(char* buf, size_t buflen) {
1533 // These buffers are small because we want this to be brief
1534 // and not use a lot of stack while generating the hs_err file.
1535 char os[100];
1536 size_t size = sizeof(os);
1537 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1538 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1539 #ifdef __APPLE__
1540 strncpy(os, "Darwin", sizeof(os));
1541 #elif __OpenBSD__
1542 strncpy(os, "OpenBSD", sizeof(os));
1543 #else
1544 strncpy(os, "BSD", sizeof(os));
1545 #endif
1546 }
1547
1548 char release[100];
1549 size = sizeof(release);
1550 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1551 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1552 // if error, leave blank
1553 strncpy(release, "", sizeof(release));
1554 }
1555 snprintf(buf, buflen, "%s %s", os, release);
1556 }
1557
1558 void os::print_os_info_brief(outputStream* st) {
1559 os::Posix::print_uname_info(st);
1560 }
1561
1562 void os::print_os_info(outputStream* st) {
1563 st->print("OS:");
1564
1565 os::Posix::print_uname_info(st);
1566
1567 os::Posix::print_rlimit_info(st);
1568
1569 os::Posix::print_load_average(st);
1570 }
1571
1572 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1573 // Nothing to do for now.
1574 }
1575
1576 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1577 unsigned int mhz;
1578 size_t size = sizeof(mhz);
1579 int mib[] = { CTL_HW, HW_CPU_FREQ };
1580 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1581 mhz = 1; // looks like an error but can be divided by
1582 } else {
1583 mhz /= 1000000; // reported in millions
1584 }
1585
1586 char model[100];
1587 size = sizeof(model);
1588 int mib_model[] = { CTL_HW, HW_MODEL };
1589 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1590 strncpy(model, cpu_arch, sizeof(model));
1591 }
1592
1593 char machine[100];
1594 size = sizeof(machine);
1595 int mib_machine[] = { CTL_HW, HW_MACHINE };
1596 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1597 strncpy(machine, "", sizeof(machine));
1598 }
1599
1600 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1601 }
1602
1603 void os::print_memory_info(outputStream* st) {
1604
1605 st->print("Memory:");
1606 st->print(" %dk page", os::vm_page_size()>>10);
1607
1608 st->print(", physical " UINT64_FORMAT "k",
1609 os::physical_memory() >> 10);
1610 st->print("(" UINT64_FORMAT "k free)",
1611 os::available_memory() >> 10);
1612 st->cr();
1613 }
1614
1615 static void print_signal_handler(outputStream* st, int sig,
1616 char* buf, size_t buflen);
1617
1618 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1619 st->print_cr("Signal Handlers:");
1620 print_signal_handler(st, SIGSEGV, buf, buflen);
1621 print_signal_handler(st, SIGBUS , buf, buflen);
1622 print_signal_handler(st, SIGFPE , buf, buflen);
1623 print_signal_handler(st, SIGPIPE, buf, buflen);
1624 print_signal_handler(st, SIGXFSZ, buf, buflen);
1625 print_signal_handler(st, SIGILL , buf, buflen);
1626 print_signal_handler(st, SR_signum, buf, buflen);
1627 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1628 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1629 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1630 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1631 }
1632
1633 static char saved_jvm_path[MAXPATHLEN] = {0};
1634
1635 // Find the full path to the current module, libjvm
1636 void os::jvm_path(char *buf, jint buflen) {
1637 // Error checking.
1638 if (buflen < MAXPATHLEN) {
1639 assert(false, "must use a large-enough buffer");
1640 buf[0] = '\0';
1641 return;
1642 }
1643 // Lazy resolve the path to current module.
1644 if (saved_jvm_path[0] != 0) {
1645 strcpy(buf, saved_jvm_path);
1646 return;
1647 }
1648
1649 char dli_fname[MAXPATHLEN];
1650 bool ret = dll_address_to_library_name(
1651 CAST_FROM_FN_PTR(address, os::jvm_path),
1652 dli_fname, sizeof(dli_fname), NULL);
1653 assert(ret, "cannot locate libjvm");
1654 char *rp = NULL;
1655 if (ret && dli_fname[0] != '\0') {
1656 rp = os::Posix::realpath(dli_fname, buf, buflen);
1657 }
1658 if (rp == NULL) {
1659 return;
1660 }
1661
1662 if (Arguments::sun_java_launcher_is_altjvm()) {
1663 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1664 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1665 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1666 // appears at the right place in the string, then assume we are
1667 // installed in a JDK and we're done. Otherwise, check for a
1668 // JAVA_HOME environment variable and construct a path to the JVM
1669 // being overridden.
1670
1671 const char *p = buf + strlen(buf) - 1;
1672 for (int count = 0; p > buf && count < 5; ++count) {
1673 for (--p; p > buf && *p != '/'; --p)
1674 /* empty */ ;
1675 }
1676
1677 if (strncmp(p, "/jre/lib/", 9) != 0) {
1678 // Look for JAVA_HOME in the environment.
1679 char* java_home_var = ::getenv("JAVA_HOME");
1680 if (java_home_var != NULL && java_home_var[0] != 0) {
1681 char* jrelib_p;
1682 int len;
1683
1684 // Check the current module name "libjvm"
1685 p = strrchr(buf, '/');
1686 assert(strstr(p, "/libjvm") == p, "invalid library name");
1687
1688 rp = os::Posix::realpath(java_home_var, buf, buflen);
1689 if (rp == NULL) {
1690 return;
1691 }
1692
1693 // determine if this is a legacy image or modules image
1694 // modules image doesn't have "jre" subdirectory
1695 len = strlen(buf);
1696 assert(len < buflen, "Ran out of buffer space");
1697 jrelib_p = buf + len;
1698
1699 // Add the appropriate library subdir
1700 snprintf(jrelib_p, buflen-len, "/jre/lib");
1701 if (0 != access(buf, F_OK)) {
1702 snprintf(jrelib_p, buflen-len, "/lib");
1703 }
1704
1705 // Add the appropriate client or server subdir
1706 len = strlen(buf);
1707 jrelib_p = buf + len;
1708 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1709 if (0 != access(buf, F_OK)) {
1710 snprintf(jrelib_p, buflen-len, "%s", "");
1711 }
1712
1713 // If the path exists within JAVA_HOME, add the JVM library name
1714 // to complete the path to JVM being overridden. Otherwise fallback
1715 // to the path to the current library.
1716 if (0 == access(buf, F_OK)) {
1717 // Use current module name "libjvm"
1718 len = strlen(buf);
1719 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1720 } else {
1721 // Fall back to path of current library
1722 rp = os::Posix::realpath(dli_fname, buf, buflen);
1723 if (rp == NULL) {
1724 return;
1725 }
1726 }
1727 }
1728 }
1729 }
1730
1731 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1732 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1733 }
1734
1735 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1736 // no prefix required, not even "_"
1737 }
1738
1739 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1740 // no suffix required
1741 }
1742
1743 ////////////////////////////////////////////////////////////////////////////////
1744 // sun.misc.Signal support
1745
1746 static volatile jint sigint_count = 0;
1747
1748 static void UserHandler(int sig, void *siginfo, void *context) {
1749 // 4511530 - sem_post is serialized and handled by the manager thread. When
1750 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1751 // don't want to flood the manager thread with sem_post requests.
1752 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1753 return;
1754 }
1755
1756 // Ctrl-C is pressed during error reporting, likely because the error
1757 // handler fails to abort. Let VM die immediately.
1758 if (sig == SIGINT && VMError::is_error_reported()) {
1759 os::die();
1760 }
1761
1762 os::signal_notify(sig);
1763 }
1764
1765 void* os::user_handler() {
1766 return CAST_FROM_FN_PTR(void*, UserHandler);
1767 }
1768
1769 extern "C" {
1770 typedef void (*sa_handler_t)(int);
1771 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1772 }
1773
1774 void* os::signal(int signal_number, void* handler) {
1775 struct sigaction sigAct, oldSigAct;
1776
1777 sigfillset(&(sigAct.sa_mask));
1778 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1779 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1780
1781 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1782 // -1 means registration failed
1783 return (void *)-1;
1784 }
1785
1786 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1787 }
1788
1789 void os::signal_raise(int signal_number) {
1790 ::raise(signal_number);
1791 }
1792
1793 // The following code is moved from os.cpp for making this
1794 // code platform specific, which it is by its very nature.
1795
1796 // Will be modified when max signal is changed to be dynamic
1797 int os::sigexitnum_pd() {
1798 return NSIG;
1799 }
1800
1801 // a counter for each possible signal value
1802 static volatile jint pending_signals[NSIG+1] = { 0 };
1803 static Semaphore* sig_sem = NULL;
1804
1805 static void jdk_misc_signal_init() {
1806 // Initialize signal structures
1807 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1808
1809 // Initialize signal semaphore
1810 sig_sem = new Semaphore();
1811 }
1812
1813 void os::signal_notify(int sig) {
1814 if (sig_sem != NULL) {
1815 Atomic::inc(&pending_signals[sig]);
1816 sig_sem->signal();
1817 } else {
1818 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1819 // initialization isn't called.
1820 assert(ReduceSignalUsage, "signal semaphore should be created");
1821 }
1822 }
1823
1824 static int check_pending_signals() {
1825 Atomic::store(0, &sigint_count);
1826 for (;;) {
1827 for (int i = 0; i < NSIG + 1; i++) {
1828 jint n = pending_signals[i];
1829 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1830 return i;
1831 }
1832 }
1833 JavaThread *thread = JavaThread::current();
1834 ThreadBlockInVM tbivm(thread);
1835
1836 bool threadIsSuspended;
1837 do {
1838 thread->set_suspend_equivalent();
1839 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1840 sig_sem->wait();
1841
1842 // were we externally suspended while we were waiting?
1843 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1844 if (threadIsSuspended) {
1845 // The semaphore has been incremented, but while we were waiting
1846 // another thread suspended us. We don't want to continue running
1847 // while suspended because that would surprise the thread that
1848 // suspended us.
1849 sig_sem->signal();
1850
1851 thread->java_suspend_self();
1852 }
1853 } while (threadIsSuspended);
1854 }
1855 }
1856
1857 int os::signal_wait() {
1858 return check_pending_signals();
1859 }
1860
1861 ////////////////////////////////////////////////////////////////////////////////
1862 // Virtual Memory
1863
1864 int os::vm_page_size() {
1865 // Seems redundant as all get out
1866 assert(os::Bsd::page_size() != -1, "must call os::init");
1867 return os::Bsd::page_size();
1868 }
1869
1870 // Solaris allocates memory by pages.
1871 int os::vm_allocation_granularity() {
1872 assert(os::Bsd::page_size() != -1, "must call os::init");
1873 return os::Bsd::page_size();
1874 }
1875
1876 // Rationale behind this function:
1877 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1878 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1879 // samples for JITted code. Here we create private executable mapping over the code cache
1880 // and then we can use standard (well, almost, as mapping can change) way to provide
1881 // info for the reporting script by storing timestamp and location of symbol
1882 void bsd_wrap_code(char* base, size_t size) {
1883 static volatile jint cnt = 0;
1884
1885 if (!UseOprofile) {
1886 return;
1887 }
1888
1889 char buf[PATH_MAX + 1];
1890 int num = Atomic::add(1, &cnt);
1891
1892 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1893 os::get_temp_directory(), os::current_process_id(), num);
1894 unlink(buf);
1895
1896 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1897
1898 if (fd != -1) {
1899 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1900 if (rv != (off_t)-1) {
1901 if (::write(fd, "", 1) == 1) {
1902 mmap(base, size,
1903 PROT_READ|PROT_WRITE|PROT_EXEC,
1904 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1905 }
1906 }
1907 ::close(fd);
1908 unlink(buf);
1909 }
1910 }
1911
1912 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1913 int err) {
1914 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1915 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1916 os::errno_name(err), err);
1917 }
1918
1919 // NOTE: Bsd kernel does not really reserve the pages for us.
1920 // All it does is to check if there are enough free pages
1921 // left at the time of mmap(). This could be a potential
1922 // problem.
1923 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1924 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1925 #ifdef __OpenBSD__
1926 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1927 if (::mprotect(addr, size, prot) == 0) {
1928 return true;
1929 }
1930 #else
1931 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1932 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1933 if (res != (uintptr_t) MAP_FAILED) {
1934 return true;
1935 }
1936 #endif
1937
1938 // Warn about any commit errors we see in non-product builds just
1939 // in case mmap() doesn't work as described on the man page.
1940 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1941
1942 return false;
1943 }
1944
1945 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1946 bool exec) {
1947 // alignment_hint is ignored on this OS
1948 return pd_commit_memory(addr, size, exec);
1949 }
1950
1951 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1952 const char* mesg) {
1953 assert(mesg != NULL, "mesg must be specified");
1954 if (!pd_commit_memory(addr, size, exec)) {
1955 // add extra info in product mode for vm_exit_out_of_memory():
1956 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1957 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1958 }
1959 }
1960
1961 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1962 size_t alignment_hint, bool exec,
1963 const char* mesg) {
1964 // alignment_hint is ignored on this OS
1965 pd_commit_memory_or_exit(addr, size, exec, mesg);
1966 }
1967
1968 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1969 }
1970
1971 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1972 ::madvise(addr, bytes, MADV_DONTNEED);
1973 }
1974
1975 void os::numa_make_global(char *addr, size_t bytes) {
1976 }
1977
1978 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1979 }
1980
1981 bool os::numa_topology_changed() { return false; }
1982
1983 size_t os::numa_get_groups_num() {
1984 return 1;
1985 }
1986
1987 int os::numa_get_group_id() {
1988 return 0;
1989 }
1990
1991 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
1992 if (size > 0) {
1993 ids[0] = 0;
1994 return 1;
1995 }
1996 return 0;
1997 }
1998
1999 bool os::get_page_info(char *start, page_info* info) {
2000 return false;
2001 }
2002
2003 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2004 return end;
2005 }
2006
2007
2008 bool os::pd_uncommit_memory(char* addr, size_t size) {
2009 #ifdef __OpenBSD__
2010 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2011 return ::mprotect(addr, size, PROT_NONE) == 0;
2012 #else
2013 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2014 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2015 return res != (uintptr_t) MAP_FAILED;
2016 #endif
2017 }
2018
2019 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2020 return os::commit_memory(addr, size, !ExecMem);
2021 }
2022
2023 // If this is a growable mapping, remove the guard pages entirely by
2024 // munmap()ping them. If not, just call uncommit_memory().
2025 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2026 return os::uncommit_memory(addr, size);
2027 }
2028
2029 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2030 // at 'requested_addr'. If there are existing memory mappings at the same
2031 // location, however, they will be overwritten. If 'fixed' is false,
2032 // 'requested_addr' is only treated as a hint, the return value may or
2033 // may not start from the requested address. Unlike Bsd mmap(), this
2034 // function returns NULL to indicate failure.
2035 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2036 char * addr;
2037 int flags;
2038
2039 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2040 if (fixed) {
2041 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2042 flags |= MAP_FIXED;
2043 }
2044
2045 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2046 // touch an uncommitted page. Otherwise, the read/write might
2047 // succeed if we have enough swap space to back the physical page.
2048 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2049 flags, -1, 0);
2050
2051 return addr == MAP_FAILED ? NULL : addr;
2052 }
2053
2054 static int anon_munmap(char * addr, size_t size) {
2055 return ::munmap(addr, size) == 0;
2056 }
2057
2058 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2059 size_t alignment_hint) {
2060 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2061 }
2062
2063 bool os::pd_release_memory(char* addr, size_t size) {
2064 return anon_munmap(addr, size);
2065 }
2066
2067 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2068 // Bsd wants the mprotect address argument to be page aligned.
2069 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2070
2071 // According to SUSv3, mprotect() should only be used with mappings
2072 // established by mmap(), and mmap() always maps whole pages. Unaligned
2073 // 'addr' likely indicates problem in the VM (e.g. trying to change
2074 // protection of malloc'ed or statically allocated memory). Check the
2075 // caller if you hit this assert.
2076 assert(addr == bottom, "sanity check");
2077
2078 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2079 return ::mprotect(bottom, size, prot) == 0;
2080 }
2081
2082 // Set protections specified
2083 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2084 bool is_committed) {
2085 unsigned int p = 0;
2086 switch (prot) {
2087 case MEM_PROT_NONE: p = PROT_NONE; break;
2088 case MEM_PROT_READ: p = PROT_READ; break;
2089 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2090 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2091 default:
2092 ShouldNotReachHere();
2093 }
2094 // is_committed is unused.
2095 return bsd_mprotect(addr, bytes, p);
2096 }
2097
2098 bool os::guard_memory(char* addr, size_t size) {
2099 return bsd_mprotect(addr, size, PROT_NONE);
2100 }
2101
2102 bool os::unguard_memory(char* addr, size_t size) {
2103 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2104 }
2105
2106 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2107 return false;
2108 }
2109
2110 // Large page support
2111
2112 static size_t _large_page_size = 0;
2113
2114 void os::large_page_init() {
2115 }
2116
2117
2118 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2119 fatal("This code is not used or maintained.");
2120
2121 // "exec" is passed in but not used. Creating the shared image for
2122 // the code cache doesn't have an SHM_X executable permission to check.
2123 assert(UseLargePages && UseSHM, "only for SHM large pages");
2124
2125 key_t key = IPC_PRIVATE;
2126 char *addr;
2127
2128 bool warn_on_failure = UseLargePages &&
2129 (!FLAG_IS_DEFAULT(UseLargePages) ||
2130 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2131
2132 // Create a large shared memory region to attach to based on size.
2133 // Currently, size is the total size of the heap
2134 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2135 if (shmid == -1) {
2136 // Possible reasons for shmget failure:
2137 // 1. shmmax is too small for Java heap.
2138 // > check shmmax value: cat /proc/sys/kernel/shmmax
2139 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2140 // 2. not enough large page memory.
2141 // > check available large pages: cat /proc/meminfo
2142 // > increase amount of large pages:
2143 // echo new_value > /proc/sys/vm/nr_hugepages
2144 // Note 1: different Bsd may use different name for this property,
2145 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2146 // Note 2: it's possible there's enough physical memory available but
2147 // they are so fragmented after a long run that they can't
2148 // coalesce into large pages. Try to reserve large pages when
2149 // the system is still "fresh".
2150 if (warn_on_failure) {
2151 warning("Failed to reserve shared memory (errno = %d).", errno);
2152 }
2153 return NULL;
2154 }
2155
2156 // attach to the region
2157 addr = (char*)shmat(shmid, req_addr, 0);
2158 int err = errno;
2159
2160 // Remove shmid. If shmat() is successful, the actual shared memory segment
2161 // will be deleted when it's detached by shmdt() or when the process
2162 // terminates. If shmat() is not successful this will remove the shared
2163 // segment immediately.
2164 shmctl(shmid, IPC_RMID, NULL);
2165
2166 if ((intptr_t)addr == -1) {
2167 if (warn_on_failure) {
2168 warning("Failed to attach shared memory (errno = %d).", err);
2169 }
2170 return NULL;
2171 }
2172
2173 // The memory is committed
2174 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2175
2176 return addr;
2177 }
2178
2179 bool os::release_memory_special(char* base, size_t bytes) {
2180 if (MemTracker::tracking_level() > NMT_minimal) {
2181 Tracker tkr(Tracker::release);
2182 // detaching the SHM segment will also delete it, see reserve_memory_special()
2183 int rslt = shmdt(base);
2184 if (rslt == 0) {
2185 tkr.record((address)base, bytes);
2186 return true;
2187 } else {
2188 return false;
2189 }
2190 } else {
2191 return shmdt(base) == 0;
2192 }
2193 }
2194
2195 size_t os::large_page_size() {
2196 return _large_page_size;
2197 }
2198
2199 // HugeTLBFS allows application to commit large page memory on demand;
2200 // with SysV SHM the entire memory region must be allocated as shared
2201 // memory.
2202 bool os::can_commit_large_page_memory() {
2203 return UseHugeTLBFS;
2204 }
2205
2206 bool os::can_execute_large_page_memory() {
2207 return UseHugeTLBFS;
2208 }
2209
2210 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2211 assert(file_desc >= 0, "file_desc is not valid");
2212 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2213 if (result != NULL) {
2214 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2215 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2216 }
2217 }
2218 return result;
2219 }
2220
2221 // Reserve memory at an arbitrary address, only if that area is
2222 // available (and not reserved for something else).
2223
2224 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2225 const int max_tries = 10;
2226 char* base[max_tries];
2227 size_t size[max_tries];
2228 const size_t gap = 0x000000;
2229
2230 // Assert only that the size is a multiple of the page size, since
2231 // that's all that mmap requires, and since that's all we really know
2232 // about at this low abstraction level. If we need higher alignment,
2233 // we can either pass an alignment to this method or verify alignment
2234 // in one of the methods further up the call chain. See bug 5044738.
2235 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2236
2237 // Repeatedly allocate blocks until the block is allocated at the
2238 // right spot.
2239
2240 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2241 // if kernel honors the hint then we can return immediately.
2242 char * addr = anon_mmap(requested_addr, bytes, false);
2243 if (addr == requested_addr) {
2244 return requested_addr;
2245 }
2246
2247 if (addr != NULL) {
2248 // mmap() is successful but it fails to reserve at the requested address
2249 anon_munmap(addr, bytes);
2250 }
2251
2252 int i;
2253 for (i = 0; i < max_tries; ++i) {
2254 base[i] = reserve_memory(bytes);
2255
2256 if (base[i] != NULL) {
2257 // Is this the block we wanted?
2258 if (base[i] == requested_addr) {
2259 size[i] = bytes;
2260 break;
2261 }
2262
2263 // Does this overlap the block we wanted? Give back the overlapped
2264 // parts and try again.
2265
2266 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2267 if (top_overlap >= 0 && top_overlap < bytes) {
2268 unmap_memory(base[i], top_overlap);
2269 base[i] += top_overlap;
2270 size[i] = bytes - top_overlap;
2271 } else {
2272 size_t bottom_overlap = base[i] + bytes - requested_addr;
2273 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2274 unmap_memory(requested_addr, bottom_overlap);
2275 size[i] = bytes - bottom_overlap;
2276 } else {
2277 size[i] = bytes;
2278 }
2279 }
2280 }
2281 }
2282
2283 // Give back the unused reserved pieces.
2284
2285 for (int j = 0; j < i; ++j) {
2286 if (base[j] != NULL) {
2287 unmap_memory(base[j], size[j]);
2288 }
2289 }
2290
2291 if (i < max_tries) {
2292 return requested_addr;
2293 } else {
2294 return NULL;
2295 }
2296 }
2297
2298 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2299 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2300 }
2301
2302 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2303 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2304 }
2305
2306 void os::naked_short_sleep(jlong ms) {
2307 struct timespec req;
2308
2309 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2310 req.tv_sec = 0;
2311 if (ms > 0) {
2312 req.tv_nsec = (ms % 1000) * 1000000;
2313 } else {
2314 req.tv_nsec = 1;
2315 }
2316
2317 nanosleep(&req, NULL);
2318
2319 return;
2320 }
2321
2322 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2323 void os::infinite_sleep() {
2324 while (true) { // sleep forever ...
2325 ::sleep(100); // ... 100 seconds at a time
2326 }
2327 }
2328
2329 // Used to convert frequent JVM_Yield() to nops
2330 bool os::dont_yield() {
2331 return DontYieldALot;
2332 }
2333
2334 void os::naked_yield() {
2335 sched_yield();
2336 }
2337
2338 ////////////////////////////////////////////////////////////////////////////////
2339 // thread priority support
2340
2341 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2342 // only supports dynamic priority, static priority must be zero. For real-time
2343 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2344 // However, for large multi-threaded applications, SCHED_RR is not only slower
2345 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2346 // of 5 runs - Sep 2005).
2347 //
2348 // The following code actually changes the niceness of kernel-thread/LWP. It
2349 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2350 // not the entire user process, and user level threads are 1:1 mapped to kernel
2351 // threads. It has always been the case, but could change in the future. For
2352 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2353 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2354
2355 #if !defined(__APPLE__)
2356 int os::java_to_os_priority[CriticalPriority + 1] = {
2357 19, // 0 Entry should never be used
2358
2359 0, // 1 MinPriority
2360 3, // 2
2361 6, // 3
2362
2363 10, // 4
2364 15, // 5 NormPriority
2365 18, // 6
2366
2367 21, // 7
2368 25, // 8
2369 28, // 9 NearMaxPriority
2370
2371 31, // 10 MaxPriority
2372
2373 31 // 11 CriticalPriority
2374 };
2375 #else
2376 // Using Mach high-level priority assignments
2377 int os::java_to_os_priority[CriticalPriority + 1] = {
2378 0, // 0 Entry should never be used (MINPRI_USER)
2379
2380 27, // 1 MinPriority
2381 28, // 2
2382 29, // 3
2383
2384 30, // 4
2385 31, // 5 NormPriority (BASEPRI_DEFAULT)
2386 32, // 6
2387
2388 33, // 7
2389 34, // 8
2390 35, // 9 NearMaxPriority
2391
2392 36, // 10 MaxPriority
2393
2394 36 // 11 CriticalPriority
2395 };
2396 #endif
2397
2398 static int prio_init() {
2399 if (ThreadPriorityPolicy == 1) {
2400 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2401 // if effective uid is not root. Perhaps, a more elegant way of doing
2402 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2403 if (geteuid() != 0) {
2404 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2405 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2406 }
2407 ThreadPriorityPolicy = 0;
2408 }
2409 }
2410 if (UseCriticalJavaThreadPriority) {
2411 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2412 }
2413 return 0;
2414 }
2415
2416 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2417 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2418
2419 #ifdef __OpenBSD__
2420 // OpenBSD pthread_setprio starves low priority threads
2421 return OS_OK;
2422 #elif defined(__FreeBSD__)
2423 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2424 #elif defined(__APPLE__) || defined(__NetBSD__)
2425 struct sched_param sp;
2426 int policy;
2427 pthread_t self = pthread_self();
2428
2429 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2430 return OS_ERR;
2431 }
2432
2433 sp.sched_priority = newpri;
2434 if (pthread_setschedparam(self, policy, &sp) != 0) {
2435 return OS_ERR;
2436 }
2437
2438 return OS_OK;
2439 #else
2440 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2441 return (ret == 0) ? OS_OK : OS_ERR;
2442 #endif
2443 }
2444
2445 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2446 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2447 *priority_ptr = java_to_os_priority[NormPriority];
2448 return OS_OK;
2449 }
2450
2451 errno = 0;
2452 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2453 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2454 #elif defined(__APPLE__) || defined(__NetBSD__)
2455 int policy;
2456 struct sched_param sp;
2457
2458 pthread_getschedparam(pthread_self(), &policy, &sp);
2459 *priority_ptr = sp.sched_priority;
2460 #else
2461 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2462 #endif
2463 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2464 }
2465
2466 // Hint to the underlying OS that a task switch would not be good.
2467 // Void return because it's a hint and can fail.
2468 void os::hint_no_preempt() {}
2469
2470 ////////////////////////////////////////////////////////////////////////////////
2471 // suspend/resume support
2472
2473 // The low-level signal-based suspend/resume support is a remnant from the
2474 // old VM-suspension that used to be for java-suspension, safepoints etc,
2475 // within hotspot. Currently used by JFR's OSThreadSampler
2476 //
2477 // The remaining code is greatly simplified from the more general suspension
2478 // code that used to be used.
2479 //
2480 // The protocol is quite simple:
2481 // - suspend:
2482 // - sends a signal to the target thread
2483 // - polls the suspend state of the osthread using a yield loop
2484 // - target thread signal handler (SR_handler) sets suspend state
2485 // and blocks in sigsuspend until continued
2486 // - resume:
2487 // - sets target osthread state to continue
2488 // - sends signal to end the sigsuspend loop in the SR_handler
2489 //
2490 // Note that the SR_lock plays no role in this suspend/resume protocol,
2491 // but is checked for NULL in SR_handler as a thread termination indicator.
2492 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2493 //
2494 // Note that resume_clear_context() and suspend_save_context() are needed
2495 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2496 // which in part is used by:
2497 // - Forte Analyzer: AsyncGetCallTrace()
2498 // - StackBanging: get_frame_at_stack_banging_point()
2499
2500 static void resume_clear_context(OSThread *osthread) {
2501 osthread->set_ucontext(NULL);
2502 osthread->set_siginfo(NULL);
2503 }
2504
2505 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2506 osthread->set_ucontext(context);
2507 osthread->set_siginfo(siginfo);
2508 }
2509
2510 // Handler function invoked when a thread's execution is suspended or
2511 // resumed. We have to be careful that only async-safe functions are
2512 // called here (Note: most pthread functions are not async safe and
2513 // should be avoided.)
2514 //
2515 // Note: sigwait() is a more natural fit than sigsuspend() from an
2516 // interface point of view, but sigwait() prevents the signal hander
2517 // from being run. libpthread would get very confused by not having
2518 // its signal handlers run and prevents sigwait()'s use with the
2519 // mutex granting granting signal.
2520 //
2521 // Currently only ever called on the VMThread or JavaThread
2522 //
2523 #ifdef __APPLE__
2524 static OSXSemaphore sr_semaphore;
2525 #else
2526 static PosixSemaphore sr_semaphore;
2527 #endif
2528
2529 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2530 // Save and restore errno to avoid confusing native code with EINTR
2531 // after sigsuspend.
2532 int old_errno = errno;
2533
2534 Thread* thread = Thread::current_or_null_safe();
2535 assert(thread != NULL, "Missing current thread in SR_handler");
2536
2537 // On some systems we have seen signal delivery get "stuck" until the signal
2538 // mask is changed as part of thread termination. Check that the current thread
2539 // has not already terminated (via SR_lock()) - else the following assertion
2540 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2541 // destructor has completed.
2542
2543 if (thread->SR_lock() == NULL) {
2544 return;
2545 }
2546
2547 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2548
2549 OSThread* osthread = thread->osthread();
2550
2551 os::SuspendResume::State current = osthread->sr.state();
2552 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2553 suspend_save_context(osthread, siginfo, context);
2554
2555 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2556 os::SuspendResume::State state = osthread->sr.suspended();
2557 if (state == os::SuspendResume::SR_SUSPENDED) {
2558 sigset_t suspend_set; // signals for sigsuspend()
2559
2560 // get current set of blocked signals and unblock resume signal
2561 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2562 sigdelset(&suspend_set, SR_signum);
2563
2564 sr_semaphore.signal();
2565 // wait here until we are resumed
2566 while (1) {
2567 sigsuspend(&suspend_set);
2568
2569 os::SuspendResume::State result = osthread->sr.running();
2570 if (result == os::SuspendResume::SR_RUNNING) {
2571 sr_semaphore.signal();
2572 break;
2573 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2574 ShouldNotReachHere();
2575 }
2576 }
2577
2578 } else if (state == os::SuspendResume::SR_RUNNING) {
2579 // request was cancelled, continue
2580 } else {
2581 ShouldNotReachHere();
2582 }
2583
2584 resume_clear_context(osthread);
2585 } else if (current == os::SuspendResume::SR_RUNNING) {
2586 // request was cancelled, continue
2587 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2588 // ignore
2589 } else {
2590 // ignore
2591 }
2592
2593 errno = old_errno;
2594 }
2595
2596
2597 static int SR_initialize() {
2598 struct sigaction act;
2599 char *s;
2600 // Get signal number to use for suspend/resume
2601 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2602 int sig = ::strtol(s, 0, 10);
2603 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2604 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2605 SR_signum = sig;
2606 } else {
2607 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2608 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2609 }
2610 }
2611
2612 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2613 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2614
2615 sigemptyset(&SR_sigset);
2616 sigaddset(&SR_sigset, SR_signum);
2617
2618 // Set up signal handler for suspend/resume
2619 act.sa_flags = SA_RESTART|SA_SIGINFO;
2620 act.sa_handler = (void (*)(int)) SR_handler;
2621
2622 // SR_signum is blocked by default.
2623 // 4528190 - We also need to block pthread restart signal (32 on all
2624 // supported Bsd platforms). Note that BsdThreads need to block
2625 // this signal for all threads to work properly. So we don't have
2626 // to use hard-coded signal number when setting up the mask.
2627 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2628
2629 if (sigaction(SR_signum, &act, 0) == -1) {
2630 return -1;
2631 }
2632
2633 // Save signal flag
2634 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2635 return 0;
2636 }
2637
2638 static int sr_notify(OSThread* osthread) {
2639 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2640 assert_status(status == 0, status, "pthread_kill");
2641 return status;
2642 }
2643
2644 // "Randomly" selected value for how long we want to spin
2645 // before bailing out on suspending a thread, also how often
2646 // we send a signal to a thread we want to resume
2647 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2648 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2649
2650 // returns true on success and false on error - really an error is fatal
2651 // but this seems the normal response to library errors
2652 static bool do_suspend(OSThread* osthread) {
2653 assert(osthread->sr.is_running(), "thread should be running");
2654 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2655
2656 // mark as suspended and send signal
2657 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2658 // failed to switch, state wasn't running?
2659 ShouldNotReachHere();
2660 return false;
2661 }
2662
2663 if (sr_notify(osthread) != 0) {
2664 ShouldNotReachHere();
2665 }
2666
2667 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2668 while (true) {
2669 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2670 break;
2671 } else {
2672 // timeout
2673 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2674 if (cancelled == os::SuspendResume::SR_RUNNING) {
2675 return false;
2676 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2677 // make sure that we consume the signal on the semaphore as well
2678 sr_semaphore.wait();
2679 break;
2680 } else {
2681 ShouldNotReachHere();
2682 return false;
2683 }
2684 }
2685 }
2686
2687 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2688 return true;
2689 }
2690
2691 static void do_resume(OSThread* osthread) {
2692 assert(osthread->sr.is_suspended(), "thread should be suspended");
2693 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2694
2695 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2696 // failed to switch to WAKEUP_REQUEST
2697 ShouldNotReachHere();
2698 return;
2699 }
2700
2701 while (true) {
2702 if (sr_notify(osthread) == 0) {
2703 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2704 if (osthread->sr.is_running()) {
2705 return;
2706 }
2707 }
2708 } else {
2709 ShouldNotReachHere();
2710 }
2711 }
2712
2713 guarantee(osthread->sr.is_running(), "Must be running!");
2714 }
2715
2716 ///////////////////////////////////////////////////////////////////////////////////
2717 // signal handling (except suspend/resume)
2718
2719 // This routine may be used by user applications as a "hook" to catch signals.
2720 // The user-defined signal handler must pass unrecognized signals to this
2721 // routine, and if it returns true (non-zero), then the signal handler must
2722 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2723 // routine will never retun false (zero), but instead will execute a VM panic
2724 // routine kill the process.
2725 //
2726 // If this routine returns false, it is OK to call it again. This allows
2727 // the user-defined signal handler to perform checks either before or after
2728 // the VM performs its own checks. Naturally, the user code would be making
2729 // a serious error if it tried to handle an exception (such as a null check
2730 // or breakpoint) that the VM was generating for its own correct operation.
2731 //
2732 // This routine may recognize any of the following kinds of signals:
2733 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2734 // It should be consulted by handlers for any of those signals.
2735 //
2736 // The caller of this routine must pass in the three arguments supplied
2737 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2738 // field of the structure passed to sigaction(). This routine assumes that
2739 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2740 //
2741 // Note that the VM will print warnings if it detects conflicting signal
2742 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2743 //
2744 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2745 void* ucontext,
2746 int abort_if_unrecognized);
2747
2748 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2749 assert(info != NULL && uc != NULL, "it must be old kernel");
2750 int orig_errno = errno; // Preserve errno value over signal handler.
2751 JVM_handle_bsd_signal(sig, info, uc, true);
2752 errno = orig_errno;
2753 }
2754
2755
2756 // This boolean allows users to forward their own non-matching signals
2757 // to JVM_handle_bsd_signal, harmlessly.
2758 bool os::Bsd::signal_handlers_are_installed = false;
2759
2760 // For signal-chaining
2761 struct sigaction sigact[NSIG];
2762 uint32_t sigs = 0;
2763 #if (32 < NSIG-1)
2764 #error "Not all signals can be encoded in sigs. Adapt its type!"
2765 #endif
2766 bool os::Bsd::libjsig_is_loaded = false;
2767 typedef struct sigaction *(*get_signal_t)(int);
2768 get_signal_t os::Bsd::get_signal_action = NULL;
2769
2770 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2771 struct sigaction *actp = NULL;
2772
2773 if (libjsig_is_loaded) {
2774 // Retrieve the old signal handler from libjsig
2775 actp = (*get_signal_action)(sig);
2776 }
2777 if (actp == NULL) {
2778 // Retrieve the preinstalled signal handler from jvm
2779 actp = get_preinstalled_handler(sig);
2780 }
2781
2782 return actp;
2783 }
2784
2785 static bool call_chained_handler(struct sigaction *actp, int sig,
2786 siginfo_t *siginfo, void *context) {
2787 // Call the old signal handler
2788 if (actp->sa_handler == SIG_DFL) {
2789 // It's more reasonable to let jvm treat it as an unexpected exception
2790 // instead of taking the default action.
2791 return false;
2792 } else if (actp->sa_handler != SIG_IGN) {
2793 if ((actp->sa_flags & SA_NODEFER) == 0) {
2794 // automaticlly block the signal
2795 sigaddset(&(actp->sa_mask), sig);
2796 }
2797
2798 sa_handler_t hand;
2799 sa_sigaction_t sa;
2800 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2801 // retrieve the chained handler
2802 if (siginfo_flag_set) {
2803 sa = actp->sa_sigaction;
2804 } else {
2805 hand = actp->sa_handler;
2806 }
2807
2808 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2809 actp->sa_handler = SIG_DFL;
2810 }
2811
2812 // try to honor the signal mask
2813 sigset_t oset;
2814 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2815
2816 // call into the chained handler
2817 if (siginfo_flag_set) {
2818 (*sa)(sig, siginfo, context);
2819 } else {
2820 (*hand)(sig);
2821 }
2822
2823 // restore the signal mask
2824 pthread_sigmask(SIG_SETMASK, &oset, 0);
2825 }
2826 // Tell jvm's signal handler the signal is taken care of.
2827 return true;
2828 }
2829
2830 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2831 bool chained = false;
2832 // signal-chaining
2833 if (UseSignalChaining) {
2834 struct sigaction *actp = get_chained_signal_action(sig);
2835 if (actp != NULL) {
2836 chained = call_chained_handler(actp, sig, siginfo, context);
2837 }
2838 }
2839 return chained;
2840 }
2841
2842 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
2843 if ((((uint32_t)1 << (sig-1)) & sigs) != 0) {
2844 return &sigact[sig];
2845 }
2846 return NULL;
2847 }
2848
2849 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
2850 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2851 sigact[sig] = oldAct;
2852 sigs |= (uint32_t)1 << (sig-1);
2853 }
2854
2855 // for diagnostic
2856 int sigflags[NSIG];
2857
2858 int os::Bsd::get_our_sigflags(int sig) {
2859 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2860 return sigflags[sig];
2861 }
2862
2863 void os::Bsd::set_our_sigflags(int sig, int flags) {
2864 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2865 if (sig > 0 && sig < NSIG) {
2866 sigflags[sig] = flags;
2867 }
2868 }
2869
2870 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2871 // Check for overwrite.
2872 struct sigaction oldAct;
2873 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2874
2875 void* oldhand = oldAct.sa_sigaction
2876 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2877 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2878 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2879 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2880 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2881 if (AllowUserSignalHandlers || !set_installed) {
2882 // Do not overwrite; user takes responsibility to forward to us.
2883 return;
2884 } else if (UseSignalChaining) {
2885 // save the old handler in jvm
2886 save_preinstalled_handler(sig, oldAct);
2887 // libjsig also interposes the sigaction() call below and saves the
2888 // old sigaction on it own.
2889 } else {
2890 fatal("Encountered unexpected pre-existing sigaction handler "
2891 "%#lx for signal %d.", (long)oldhand, sig);
2892 }
2893 }
2894
2895 struct sigaction sigAct;
2896 sigfillset(&(sigAct.sa_mask));
2897 sigAct.sa_handler = SIG_DFL;
2898 if (!set_installed) {
2899 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2900 } else {
2901 sigAct.sa_sigaction = signalHandler;
2902 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2903 }
2904 #ifdef __APPLE__
2905 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2906 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2907 // if the signal handler declares it will handle it on alternate stack.
2908 // Notice we only declare we will handle it on alt stack, but we are not
2909 // actually going to use real alt stack - this is just a workaround.
2910 // Please see ux_exception.c, method catch_mach_exception_raise for details
2911 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2912 if (sig == SIGSEGV) {
2913 sigAct.sa_flags |= SA_ONSTACK;
2914 }
2915 #endif
2916
2917 // Save flags, which are set by ours
2918 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2919 sigflags[sig] = sigAct.sa_flags;
2920
2921 int ret = sigaction(sig, &sigAct, &oldAct);
2922 assert(ret == 0, "check");
2923
2924 void* oldhand2 = oldAct.sa_sigaction
2925 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2926 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2927 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2928 }
2929
2930 // install signal handlers for signals that HotSpot needs to
2931 // handle in order to support Java-level exception handling.
2932
2933 void os::Bsd::install_signal_handlers() {
2934 if (!signal_handlers_are_installed) {
2935 signal_handlers_are_installed = true;
2936
2937 // signal-chaining
2938 typedef void (*signal_setting_t)();
2939 signal_setting_t begin_signal_setting = NULL;
2940 signal_setting_t end_signal_setting = NULL;
2941 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2942 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2943 if (begin_signal_setting != NULL) {
2944 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2945 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2946 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2947 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2948 libjsig_is_loaded = true;
2949 assert(UseSignalChaining, "should enable signal-chaining");
2950 }
2951 if (libjsig_is_loaded) {
2952 // Tell libjsig jvm is setting signal handlers
2953 (*begin_signal_setting)();
2954 }
2955
2956 set_signal_handler(SIGSEGV, true);
2957 set_signal_handler(SIGPIPE, true);
2958 set_signal_handler(SIGBUS, true);
2959 set_signal_handler(SIGILL, true);
2960 set_signal_handler(SIGFPE, true);
2961 set_signal_handler(SIGXFSZ, true);
2962
2963 #if defined(__APPLE__)
2964 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2965 // signals caught and handled by the JVM. To work around this, we reset the mach task
2966 // signal handler that's placed on our process by CrashReporter. This disables
2967 // CrashReporter-based reporting.
2968 //
2969 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2970 // on caught fatal signals.
2971 //
2972 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2973 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2974 // exception handling, while leaving the standard BSD signal handlers functional.
2975 kern_return_t kr;
2976 kr = task_set_exception_ports(mach_task_self(),
2977 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2978 MACH_PORT_NULL,
2979 EXCEPTION_STATE_IDENTITY,
2980 MACHINE_THREAD_STATE);
2981
2982 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2983 #endif
2984
2985 if (libjsig_is_loaded) {
2986 // Tell libjsig jvm finishes setting signal handlers
2987 (*end_signal_setting)();
2988 }
2989
2990 // We don't activate signal checker if libjsig is in place, we trust ourselves
2991 // and if UserSignalHandler is installed all bets are off
2992 if (CheckJNICalls) {
2993 if (libjsig_is_loaded) {
2994 if (PrintJNIResolving) {
2995 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
2996 }
2997 check_signals = false;
2998 }
2999 if (AllowUserSignalHandlers) {
3000 if (PrintJNIResolving) {
3001 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3002 }
3003 check_signals = false;
3004 }
3005 }
3006 }
3007 }
3008
3009
3010 /////
3011 // glibc on Bsd platform uses non-documented flag
3012 // to indicate, that some special sort of signal
3013 // trampoline is used.
3014 // We will never set this flag, and we should
3015 // ignore this flag in our diagnostic
3016 #ifdef SIGNIFICANT_SIGNAL_MASK
3017 #undef SIGNIFICANT_SIGNAL_MASK
3018 #endif
3019 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3020
3021 static const char* get_signal_handler_name(address handler,
3022 char* buf, int buflen) {
3023 int offset;
3024 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3025 if (found) {
3026 // skip directory names
3027 const char *p1, *p2;
3028 p1 = buf;
3029 size_t len = strlen(os::file_separator());
3030 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3031 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3032 } else {
3033 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3034 }
3035 return buf;
3036 }
3037
3038 static void print_signal_handler(outputStream* st, int sig,
3039 char* buf, size_t buflen) {
3040 struct sigaction sa;
3041
3042 sigaction(sig, NULL, &sa);
3043
3044 // See comment for SIGNIFICANT_SIGNAL_MASK define
3045 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3046
3047 st->print("%s: ", os::exception_name(sig, buf, buflen));
3048
3049 address handler = (sa.sa_flags & SA_SIGINFO)
3050 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3051 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3052
3053 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3054 st->print("SIG_DFL");
3055 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3056 st->print("SIG_IGN");
3057 } else {
3058 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3059 }
3060
3061 st->print(", sa_mask[0]=");
3062 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3063
3064 address rh = VMError::get_resetted_sighandler(sig);
3065 // May be, handler was resetted by VMError?
3066 if (rh != NULL) {
3067 handler = rh;
3068 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3069 }
3070
3071 st->print(", sa_flags=");
3072 os::Posix::print_sa_flags(st, sa.sa_flags);
3073
3074 // Check: is it our handler?
3075 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3076 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3077 // It is our signal handler
3078 // check for flags, reset system-used one!
3079 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3080 st->print(
3081 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3082 os::Bsd::get_our_sigflags(sig));
3083 }
3084 }
3085 st->cr();
3086 }
3087
3088
3089 #define DO_SIGNAL_CHECK(sig) \
3090 do { \
3091 if (!sigismember(&check_signal_done, sig)) { \
3092 os::Bsd::check_signal_handler(sig); \
3093 } \
3094 } while (0)
3095
3096 // This method is a periodic task to check for misbehaving JNI applications
3097 // under CheckJNI, we can add any periodic checks here
3098
3099 void os::run_periodic_checks() {
3100
3101 if (check_signals == false) return;
3102
3103 // SEGV and BUS if overridden could potentially prevent
3104 // generation of hs*.log in the event of a crash, debugging
3105 // such a case can be very challenging, so we absolutely
3106 // check the following for a good measure:
3107 DO_SIGNAL_CHECK(SIGSEGV);
3108 DO_SIGNAL_CHECK(SIGILL);
3109 DO_SIGNAL_CHECK(SIGFPE);
3110 DO_SIGNAL_CHECK(SIGBUS);
3111 DO_SIGNAL_CHECK(SIGPIPE);
3112 DO_SIGNAL_CHECK(SIGXFSZ);
3113
3114
3115 // ReduceSignalUsage allows the user to override these handlers
3116 // see comments at the very top and jvm_md.h
3117 if (!ReduceSignalUsage) {
3118 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3119 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3120 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3121 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3122 }
3123
3124 DO_SIGNAL_CHECK(SR_signum);
3125 }
3126
3127 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3128
3129 static os_sigaction_t os_sigaction = NULL;
3130
3131 void os::Bsd::check_signal_handler(int sig) {
3132 char buf[O_BUFLEN];
3133 address jvmHandler = NULL;
3134
3135
3136 struct sigaction act;
3137 if (os_sigaction == NULL) {
3138 // only trust the default sigaction, in case it has been interposed
3139 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3140 if (os_sigaction == NULL) return;
3141 }
3142
3143 os_sigaction(sig, (struct sigaction*)NULL, &act);
3144
3145
3146 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3147
3148 address thisHandler = (act.sa_flags & SA_SIGINFO)
3149 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3150 : CAST_FROM_FN_PTR(address, act.sa_handler);
3151
3152
3153 switch (sig) {
3154 case SIGSEGV:
3155 case SIGBUS:
3156 case SIGFPE:
3157 case SIGPIPE:
3158 case SIGILL:
3159 case SIGXFSZ:
3160 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3161 break;
3162
3163 case SHUTDOWN1_SIGNAL:
3164 case SHUTDOWN2_SIGNAL:
3165 case SHUTDOWN3_SIGNAL:
3166 case BREAK_SIGNAL:
3167 jvmHandler = (address)user_handler();
3168 break;
3169
3170 default:
3171 if (sig == SR_signum) {
3172 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3173 } else {
3174 return;
3175 }
3176 break;
3177 }
3178
3179 if (thisHandler != jvmHandler) {
3180 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3181 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3182 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3183 // No need to check this sig any longer
3184 sigaddset(&check_signal_done, sig);
3185 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3186 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3187 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3188 exception_name(sig, buf, O_BUFLEN));
3189 }
3190 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3191 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3192 tty->print("expected:");
3193 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3194 tty->cr();
3195 tty->print(" found:");
3196 os::Posix::print_sa_flags(tty, act.sa_flags);
3197 tty->cr();
3198 // No need to check this sig any longer
3199 sigaddset(&check_signal_done, sig);
3200 }
3201
3202 // Dump all the signal
3203 if (sigismember(&check_signal_done, sig)) {
3204 print_signal_handlers(tty, buf, O_BUFLEN);
3205 }
3206 }
3207
3208 extern void report_error(char* file_name, int line_no, char* title,
3209 char* format, ...);
3210
3211 // this is called _before_ the most of global arguments have been parsed
3212 void os::init(void) {
3213 char dummy; // used to get a guess on initial stack address
3214
3215 // With BsdThreads the JavaMain thread pid (primordial thread)
3216 // is different than the pid of the java launcher thread.
3217 // So, on Bsd, the launcher thread pid is passed to the VM
3218 // via the sun.java.launcher.pid property.
3219 // Use this property instead of getpid() if it was correctly passed.
3220 // See bug 6351349.
3221 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3222
3223 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3224
3225 clock_tics_per_sec = CLK_TCK;
3226
3227 init_random(1234567);
3228
3229 Bsd::set_page_size(getpagesize());
3230 if (Bsd::page_size() == -1) {
3231 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3232 }
3233 init_page_sizes((size_t) Bsd::page_size());
3234
3235 Bsd::initialize_system_info();
3236
3237 // _main_thread points to the thread that created/loaded the JVM.
3238 Bsd::_main_thread = pthread_self();
3239
3240 Bsd::clock_init();
3241 initial_time_count = javaTimeNanos();
3242
3243 #ifdef __APPLE__
3244 // XXXDARWIN
3245 // Work around the unaligned VM callbacks in hotspot's
3246 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3247 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3248 // alignment when doing symbol lookup. To work around this, we force early
3249 // binding of all symbols now, thus binding when alignment is known-good.
3250 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3251 #endif
3252
3253 os::Posix::init();
3254 }
3255
3256 // To install functions for atexit system call
3257 extern "C" {
3258 static void perfMemory_exit_helper() {
3259 perfMemory_exit();
3260 }
3261 }
3262
3263 // this is called _after_ the global arguments have been parsed
3264 jint os::init_2(void) {
3265
3266 os::Posix::init_2();
3267
3268 // initialize suspend/resume support - must do this before signal_sets_init()
3269 if (SR_initialize() != 0) {
3270 perror("SR_initialize failed");
3271 return JNI_ERR;
3272 }
3273
3274 Bsd::signal_sets_init();
3275 Bsd::install_signal_handlers();
3276 // Initialize data for jdk.internal.misc.Signal
3277 if (!ReduceSignalUsage) {
3278 jdk_misc_signal_init();
3279 }
3280
3281 // Check and sets minimum stack sizes against command line options
3282 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3283 return JNI_ERR;
3284 }
3285
3286 if (MaxFDLimit) {
3287 // set the number of file descriptors to max. print out error
3288 // if getrlimit/setrlimit fails but continue regardless.
3289 struct rlimit nbr_files;
3290 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3291 if (status != 0) {
3292 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3293 } else {
3294 nbr_files.rlim_cur = nbr_files.rlim_max;
3295
3296 #ifdef __APPLE__
3297 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3298 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3299 // be used instead
3300 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3301 #endif
3302
3303 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3304 if (status != 0) {
3305 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3306 }
3307 }
3308 }
3309
3310 // at-exit methods are called in the reverse order of their registration.
3311 // atexit functions are called on return from main or as a result of a
3312 // call to exit(3C). There can be only 32 of these functions registered
3313 // and atexit() does not set errno.
3314
3315 if (PerfAllowAtExitRegistration) {
3316 // only register atexit functions if PerfAllowAtExitRegistration is set.
3317 // atexit functions can be delayed until process exit time, which
3318 // can be problematic for embedded VM situations. Embedded VMs should
3319 // call DestroyJavaVM() to assure that VM resources are released.
3320
3321 // note: perfMemory_exit_helper atexit function may be removed in
3322 // the future if the appropriate cleanup code can be added to the
3323 // VM_Exit VMOperation's doit method.
3324 if (atexit(perfMemory_exit_helper) != 0) {
3325 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3326 }
3327 }
3328
3329 // initialize thread priority policy
3330 prio_init();
3331
3332 #ifdef __APPLE__
3333 // dynamically link to objective c gc registration
3334 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3335 if (handleLibObjc != NULL) {
3336 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3337 }
3338 #endif
3339
3340 return JNI_OK;
3341 }
3342
3343 // Mark the polling page as unreadable
3344 void os::make_polling_page_unreadable(void) {
3345 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3346 fatal("Could not disable polling page");
3347 }
3348 }
3349
3350 // Mark the polling page as readable
3351 void os::make_polling_page_readable(void) {
3352 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3353 fatal("Could not enable polling page");
3354 }
3355 }
3356
3357 int os::active_processor_count() {
3358 // User has overridden the number of active processors
3359 if (ActiveProcessorCount > 0) {
3360 log_trace(os)("active_processor_count: "
3361 "active processor count set by user : %d",
3362 ActiveProcessorCount);
3363 return ActiveProcessorCount;
3364 }
3365
3366 return _processor_count;
3367 }
3368
3369 void os::set_native_thread_name(const char *name) {
3370 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3371 // This is only supported in Snow Leopard and beyond
3372 if (name != NULL) {
3373 // Add a "Java: " prefix to the name
3374 char buf[MAXTHREADNAMESIZE];
3375 snprintf(buf, sizeof(buf), "Java: %s", name);
3376 pthread_setname_np(buf);
3377 }
3378 #endif
3379 }
3380
3381 bool os::distribute_processes(uint length, uint* distribution) {
3382 // Not yet implemented.
3383 return false;
3384 }
3385
3386 bool os::bind_to_processor(uint processor_id) {
3387 // Not yet implemented.
3388 return false;
3389 }
3390
3391 void os::SuspendedThreadTask::internal_do_task() {
3392 if (do_suspend(_thread->osthread())) {
3393 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3394 do_task(context);
3395 do_resume(_thread->osthread());
3396 }
3397 }
3398
3399 ////////////////////////////////////////////////////////////////////////////////
3400 // debug support
3401
3402 bool os::find(address addr, outputStream* st) {
3403 Dl_info dlinfo;
3404 memset(&dlinfo, 0, sizeof(dlinfo));
3405 if (dladdr(addr, &dlinfo) != 0) {
3406 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3407 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3408 st->print("%s+%#x", dlinfo.dli_sname,
3409 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3410 } else if (dlinfo.dli_fbase != NULL) {
3411 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3412 } else {
3413 st->print("<absolute address>");
3414 }
3415 if (dlinfo.dli_fname != NULL) {
3416 st->print(" in %s", dlinfo.dli_fname);
3417 }
3418 if (dlinfo.dli_fbase != NULL) {
3419 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3420 }
3421 st->cr();
3422
3423 if (Verbose) {
3424 // decode some bytes around the PC
3425 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3426 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3427 address lowest = (address) dlinfo.dli_sname;
3428 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3429 if (begin < lowest) begin = lowest;
3430 Dl_info dlinfo2;
3431 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3432 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3433 end = (address) dlinfo2.dli_saddr;
3434 }
3435 Disassembler::decode(begin, end, st);
3436 }
3437 return true;
3438 }
3439 return false;
3440 }
3441
3442 ////////////////////////////////////////////////////////////////////////////////
3443 // misc
3444
3445 // This does not do anything on Bsd. This is basically a hook for being
3446 // able to use structured exception handling (thread-local exception filters)
3447 // on, e.g., Win32.
3448 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3449 const methodHandle& method, JavaCallArguments* args,
3450 Thread* thread) {
3451 f(value, method, args, thread);
3452 }
3453
3454 void os::print_statistics() {
3455 }
3456
3457 bool os::message_box(const char* title, const char* message) {
3458 int i;
3459 fdStream err(defaultStream::error_fd());
3460 for (i = 0; i < 78; i++) err.print_raw("=");
3461 err.cr();
3462 err.print_raw_cr(title);
3463 for (i = 0; i < 78; i++) err.print_raw("-");
3464 err.cr();
3465 err.print_raw_cr(message);
3466 for (i = 0; i < 78; i++) err.print_raw("=");
3467 err.cr();
3468
3469 char buf[16];
3470 // Prevent process from exiting upon "read error" without consuming all CPU
3471 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3472
3473 return buf[0] == 'y' || buf[0] == 'Y';
3474 }
3475
3476 static inline struct timespec get_mtime(const char* filename) {
3477 struct stat st;
3478 int ret = os::stat(filename, &st);
3479 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
3480 #ifdef __APPLE__
3481 return st.st_mtimespec;
3482 #else
3483 return st.st_mtim;
3484 #endif
3485 }
3486
3487 int os::compare_file_modified_times(const char* file1, const char* file2) {
3488 struct timespec filetime1 = get_mtime(file1);
3489 struct timespec filetime2 = get_mtime(file2);
3490 int diff = filetime1.tv_sec - filetime2.tv_sec;
3491 if (diff == 0) {
3492 return filetime1.tv_nsec - filetime2.tv_nsec;
3493 }
3494 return diff;
3495 }
3496
3497 // Is a (classpath) directory empty?
3498 bool os::dir_is_empty(const char* path) {
3499 DIR *dir = NULL;
3500 struct dirent *ptr;
3501
3502 dir = opendir(path);
3503 if (dir == NULL) return true;
3504
3505 // Scan the directory
3506 bool result = true;
3507 char buf[sizeof(struct dirent) + MAX_PATH];
3508 while (result && (ptr = ::readdir(dir)) != NULL) {
3509 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3510 result = false;
3511 }
3512 }
3513 closedir(dir);
3514 return result;
3515 }
3516
3517 // This code originates from JDK's sysOpen and open64_w
3518 // from src/solaris/hpi/src/system_md.c
3519
3520 int os::open(const char *path, int oflag, int mode) {
3521 if (strlen(path) > MAX_PATH - 1) {
3522 errno = ENAMETOOLONG;
3523 return -1;
3524 }
3525 int fd;
3526
3527 fd = ::open(path, oflag, mode);
3528 if (fd == -1) return -1;
3529
3530 // If the open succeeded, the file might still be a directory
3531 {
3532 struct stat buf;
3533 int ret = ::fstat(fd, &buf);
3534 int st_mode = buf.st_mode;
3535
3536 if (ret != -1) {
3537 if ((st_mode & S_IFMT) == S_IFDIR) {
3538 errno = EISDIR;
3539 ::close(fd);
3540 return -1;
3541 }
3542 } else {
3543 ::close(fd);
3544 return -1;
3545 }
3546 }
3547
3548 // All file descriptors that are opened in the JVM and not
3549 // specifically destined for a subprocess should have the
3550 // close-on-exec flag set. If we don't set it, then careless 3rd
3551 // party native code might fork and exec without closing all
3552 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3553 // UNIXProcess.c), and this in turn might:
3554 //
3555 // - cause end-of-file to fail to be detected on some file
3556 // descriptors, resulting in mysterious hangs, or
3557 //
3558 // - might cause an fopen in the subprocess to fail on a system
3559 // suffering from bug 1085341.
3560 //
3561 // (Yes, the default setting of the close-on-exec flag is a Unix
3562 // design flaw)
3563 //
3564 // See:
3565 // 1085341: 32-bit stdio routines should support file descriptors >255
3566 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3567 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3568 //
3569 #ifdef FD_CLOEXEC
3570 {
3571 int flags = ::fcntl(fd, F_GETFD);
3572 if (flags != -1) {
3573 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3574 }
3575 }
3576 #endif
3577
3578 return fd;
3579 }
3580
3581
3582 // create binary file, rewriting existing file if required
3583 int os::create_binary_file(const char* path, bool rewrite_existing) {
3584 int oflags = O_WRONLY | O_CREAT;
3585 if (!rewrite_existing) {
3586 oflags |= O_EXCL;
3587 }
3588 return ::open(path, oflags, S_IREAD | S_IWRITE);
3589 }
3590
3591 // return current position of file pointer
3592 jlong os::current_file_offset(int fd) {
3593 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3594 }
3595
3596 // move file pointer to the specified offset
3597 jlong os::seek_to_file_offset(int fd, jlong offset) {
3598 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3599 }
3600
3601 // This code originates from JDK's sysAvailable
3602 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3603
3604 int os::available(int fd, jlong *bytes) {
3605 jlong cur, end;
3606 int mode;
3607 struct stat buf;
3608
3609 if (::fstat(fd, &buf) >= 0) {
3610 mode = buf.st_mode;
3611 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3612 int n;
3613 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3614 *bytes = n;
3615 return 1;
3616 }
3617 }
3618 }
3619 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3620 return 0;
3621 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3622 return 0;
3623 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3624 return 0;
3625 }
3626 *bytes = end - cur;
3627 return 1;
3628 }
3629
3630 // Map a block of memory.
3631 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3632 char *addr, size_t bytes, bool read_only,
3633 bool allow_exec) {
3634 int prot;
3635 int flags;
3636
3637 if (read_only) {
3638 prot = PROT_READ;
3639 flags = MAP_SHARED;
3640 } else {
3641 prot = PROT_READ | PROT_WRITE;
3642 flags = MAP_PRIVATE;
3643 }
3644
3645 if (allow_exec) {
3646 prot |= PROT_EXEC;
3647 }
3648
3649 if (addr != NULL) {
3650 flags |= MAP_FIXED;
3651 }
3652
3653 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3654 fd, file_offset);
3655 if (mapped_address == MAP_FAILED) {
3656 return NULL;
3657 }
3658 return mapped_address;
3659 }
3660
3661
3662 // Remap a block of memory.
3663 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3664 char *addr, size_t bytes, bool read_only,
3665 bool allow_exec) {
3666 // same as map_memory() on this OS
3667 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3668 allow_exec);
3669 }
3670
3671
3672 // Unmap a block of memory.
3673 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3674 return munmap(addr, bytes) == 0;
3675 }
3676
3677 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3678 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3679 // of a thread.
3680 //
3681 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3682 // the fast estimate available on the platform.
3683
3684 jlong os::current_thread_cpu_time() {
3685 #ifdef __APPLE__
3686 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3687 #else
3688 Unimplemented();
3689 return 0;
3690 #endif
3691 }
3692
3693 jlong os::thread_cpu_time(Thread* thread) {
3694 #ifdef __APPLE__
3695 return os::thread_cpu_time(thread, true /* user + sys */);
3696 #else
3697 Unimplemented();
3698 return 0;
3699 #endif
3700 }
3701
3702 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3703 #ifdef __APPLE__
3704 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3705 #else
3706 Unimplemented();
3707 return 0;
3708 #endif
3709 }
3710
3711 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3712 #ifdef __APPLE__
3713 struct thread_basic_info tinfo;
3714 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3715 kern_return_t kr;
3716 thread_t mach_thread;
3717
3718 mach_thread = thread->osthread()->thread_id();
3719 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3720 if (kr != KERN_SUCCESS) {
3721 return -1;
3722 }
3723
3724 if (user_sys_cpu_time) {
3725 jlong nanos;
3726 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3727 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3728 return nanos;
3729 } else {
3730 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3731 }
3732 #else
3733 Unimplemented();
3734 return 0;
3735 #endif
3736 }
3737
3738
3739 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3740 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3741 info_ptr->may_skip_backward = false; // elapsed time not wall time
3742 info_ptr->may_skip_forward = false; // elapsed time not wall time
3743 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3744 }
3745
3746 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3747 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3748 info_ptr->may_skip_backward = false; // elapsed time not wall time
3749 info_ptr->may_skip_forward = false; // elapsed time not wall time
3750 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3751 }
3752
3753 bool os::is_thread_cpu_time_supported() {
3754 #ifdef __APPLE__
3755 return true;
3756 #else
3757 return false;
3758 #endif
3759 }
3760
3761 // System loadavg support. Returns -1 if load average cannot be obtained.
3762 // Bsd doesn't yet have a (official) notion of processor sets,
3763 // so just return the system wide load average.
3764 int os::loadavg(double loadavg[], int nelem) {
3765 return ::getloadavg(loadavg, nelem);
3766 }
3767
3768 void os::pause() {
3769 char filename[MAX_PATH];
3770 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3771 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3772 } else {
3773 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3774 }
3775
3776 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3777 if (fd != -1) {
3778 struct stat buf;
3779 ::close(fd);
3780 while (::stat(filename, &buf) == 0) {
3781 (void)::poll(NULL, 0, 100);
3782 }
3783 } else {
3784 jio_fprintf(stderr,
3785 "Could not open pause file '%s', continuing immediately.\n", filename);
3786 }
3787 }
3788
3789 // Darwin has no "environ" in a dynamic library.
3790 #ifdef __APPLE__
3791 #include <crt_externs.h>
3792 #define environ (*_NSGetEnviron())
3793 #else
3794 extern char** environ;
3795 #endif
3796
3797 // Run the specified command in a separate process. Return its exit value,
3798 // or -1 on failure (e.g. can't fork a new process).
3799 // Unlike system(), this function can be called from signal handler. It
3800 // doesn't block SIGINT et al.
3801 int os::fork_and_exec(char* cmd) {
3802 const char * argv[4] = {"sh", "-c", cmd, NULL};
3803
3804 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3805 // pthread_atfork handlers and reset pthread library. All we need is a
3806 // separate process to execve. Make a direct syscall to fork process.
3807 // On IA64 there's no fork syscall, we have to use fork() and hope for
3808 // the best...
3809 pid_t pid = fork();
3810
3811 if (pid < 0) {
3812 // fork failed
3813 return -1;
3814
3815 } else if (pid == 0) {
3816 // child process
3817
3818 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3819 // first to kill every thread on the thread list. Because this list is
3820 // not reset by fork() (see notes above), execve() will instead kill
3821 // every thread in the parent process. We know this is the only thread
3822 // in the new process, so make a system call directly.
3823 // IA64 should use normal execve() from glibc to match the glibc fork()
3824 // above.
3825 execve("/bin/sh", (char* const*)argv, environ);
3826
3827 // execve failed
3828 _exit(-1);
3829
3830 } else {
3831 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3832 // care about the actual exit code, for now.
3833
3834 int status;
3835
3836 // Wait for the child process to exit. This returns immediately if
3837 // the child has already exited. */
3838 while (waitpid(pid, &status, 0) < 0) {
3839 switch (errno) {
3840 case ECHILD: return 0;
3841 case EINTR: break;
3842 default: return -1;
3843 }
3844 }
3845
3846 if (WIFEXITED(status)) {
3847 // The child exited normally; get its exit code.
3848 return WEXITSTATUS(status);
3849 } else if (WIFSIGNALED(status)) {
3850 // The child exited because of a signal
3851 // The best value to return is 0x80 + signal number,
3852 // because that is what all Unix shells do, and because
3853 // it allows callers to distinguish between process exit and
3854 // process death by signal.
3855 return 0x80 + WTERMSIG(status);
3856 } else {
3857 // Unknown exit code; pass it through
3858 return status;
3859 }
3860 }
3861 }
3862
3863 // Get the default path to the core file
3864 // Returns the length of the string
3865 int os::get_core_path(char* buffer, size_t bufferSize) {
3866 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
3867
3868 // Truncate if theoretical string was longer than bufferSize
3869 n = MIN2(n, (int)bufferSize);
3870
3871 return n;
3872 }
3873
3874 #ifndef PRODUCT
3875 void TestReserveMemorySpecial_test() {
3876 // No tests available for this platform
3877 }
3878 #endif
3879
3880 bool os::start_debugging(char *buf, int buflen) {
3881 int len = (int)strlen(buf);
3882 char *p = &buf[len];
3883
3884 jio_snprintf(p, buflen-len,
3885 "\n\n"
3886 "Do you want to debug the problem?\n\n"
3887 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3888 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3889 "Otherwise, press RETURN to abort...",
3890 os::current_process_id(), os::current_process_id(),
3891 os::current_thread_id(), os::current_thread_id());
3892
3893 bool yes = os::message_box("Unexpected Error", buf);
3894
3895 if (yes) {
3896 // yes, user asked VM to launch debugger
3897 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3898 os::current_process_id(), os::current_process_id());
3899
3900 os::fork_and_exec(buf);
3901 yes = false;
3902 }
3903 return yes;
3904 }