1 /* 2 * Copyright (c) 1999, 2015, 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 #include "utilities/globalDefinitions.hpp" 26 #include "prims/jvm.h" 27 #include "semaphore_posix.hpp" 28 #include "runtime/frame.inline.hpp" 29 #include "runtime/interfaceSupport.hpp" 30 #include "runtime/os.hpp" 31 #include "utilities/vmError.hpp" 32 33 #include <signal.h> 34 #include <unistd.h> 35 #include <sys/resource.h> 36 #include <sys/utsname.h> 37 #include <pthread.h> 38 #include <semaphore.h> 39 #include <signal.h> 40 41 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 42 43 // Todo: provide a os::get_max_process_id() or similar. Number of processes 44 // may have been configured, can be read more accurately from proc fs etc. 45 #ifndef MAX_PID 46 #define MAX_PID INT_MAX 47 #endif 48 #define IS_VALID_PID(p) (p > 0 && p < MAX_PID) 49 50 // Check core dump limit and report possible place where core can be found 51 void os::check_dump_limit(char* buffer, size_t bufferSize) { 52 int n; 53 struct rlimit rlim; 54 bool success; 55 56 char core_path[PATH_MAX]; 57 n = get_core_path(core_path, PATH_MAX); 58 59 if (n <= 0) { 60 jio_snprintf(buffer, bufferSize, "core.%d (may not exist)", current_process_id()); 61 success = true; 62 #ifdef LINUX 63 } else if (core_path[0] == '"') { // redirect to user process 64 jio_snprintf(buffer, bufferSize, "Core dumps may be processed with %s", core_path); 65 success = true; 66 #endif 67 } else if (getrlimit(RLIMIT_CORE, &rlim) != 0) { 68 jio_snprintf(buffer, bufferSize, "%s (may not exist)", core_path); 69 success = true; 70 } else { 71 switch(rlim.rlim_cur) { 72 case RLIM_INFINITY: 73 jio_snprintf(buffer, bufferSize, "%s", core_path); 74 success = true; 75 break; 76 case 0: 77 jio_snprintf(buffer, bufferSize, "Core dumps have been disabled. To enable core dumping, try \"ulimit -c unlimited\" before starting Java again"); 78 success = false; 79 break; 80 default: 81 jio_snprintf(buffer, bufferSize, "%s (max size %lu kB). To ensure a full core dump, try \"ulimit -c unlimited\" before starting Java again", core_path, (unsigned long)(rlim.rlim_cur >> 10)); 82 success = true; 83 break; 84 } 85 } 86 87 VMError::record_coredump_status(buffer, success); 88 } 89 90 int os::get_native_stack(address* stack, int frames, int toSkip) { 91 #ifdef _NMT_NOINLINE_ 92 toSkip++; 93 #endif 94 95 int frame_idx = 0; 96 int num_of_frames; // number of frames captured 97 frame fr = os::current_frame(); 98 while (fr.pc() && frame_idx < frames) { 99 if (toSkip > 0) { 100 toSkip --; 101 } else { 102 stack[frame_idx ++] = fr.pc(); 103 } 104 if (fr.fp() == NULL || fr.cb() != NULL || 105 fr.sender_pc() == NULL || os::is_first_C_frame(&fr)) break; 106 107 if (fr.sender_pc() && !os::is_first_C_frame(&fr)) { 108 fr = os::get_sender_for_C_frame(&fr); 109 } else { 110 break; 111 } 112 } 113 num_of_frames = frame_idx; 114 for (; frame_idx < frames; frame_idx ++) { 115 stack[frame_idx] = NULL; 116 } 117 118 return num_of_frames; 119 } 120 121 122 bool os::unsetenv(const char* name) { 123 assert(name != NULL, "Null pointer"); 124 return (::unsetenv(name) == 0); 125 } 126 127 int os::get_last_error() { 128 return errno; 129 } 130 131 bool os::is_debugger_attached() { 132 // not implemented 133 return false; 134 } 135 136 void os::wait_for_keypress_at_exit(void) { 137 // don't do anything on posix platforms 138 return; 139 } 140 141 // Multiple threads can race in this code, and can remap over each other with MAP_FIXED, 142 // so on posix, unmap the section at the start and at the end of the chunk that we mapped 143 // rather than unmapping and remapping the whole chunk to get requested alignment. 144 char* os::reserve_memory_aligned(size_t size, size_t alignment) { 145 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0, 146 "Alignment must be a multiple of allocation granularity (page size)"); 147 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned"); 148 149 size_t extra_size = size + alignment; 150 assert(extra_size >= size, "overflow, size is too large to allow alignment"); 151 152 char* extra_base = os::reserve_memory(extra_size, NULL, alignment); 153 154 if (extra_base == NULL) { 155 return NULL; 156 } 157 158 // Do manual alignment 159 char* aligned_base = (char*) align_size_up((uintptr_t) extra_base, alignment); 160 161 // [ | | ] 162 // ^ extra_base 163 // ^ extra_base + begin_offset == aligned_base 164 // extra_base + begin_offset + size ^ 165 // extra_base + extra_size ^ 166 // |<>| == begin_offset 167 // end_offset == |<>| 168 size_t begin_offset = aligned_base - extra_base; 169 size_t end_offset = (extra_base + extra_size) - (aligned_base + size); 170 171 if (begin_offset > 0) { 172 os::release_memory(extra_base, begin_offset); 173 } 174 175 if (end_offset > 0) { 176 os::release_memory(extra_base + begin_offset + size, end_offset); 177 } 178 179 return aligned_base; 180 } 181 182 void os::Posix::print_load_average(outputStream* st) { 183 st->print("load average:"); 184 double loadavg[3]; 185 os::loadavg(loadavg, 3); 186 st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]); 187 st->cr(); 188 } 189 190 void os::Posix::print_rlimit_info(outputStream* st) { 191 st->print("rlimit:"); 192 struct rlimit rlim; 193 194 st->print(" STACK "); 195 getrlimit(RLIMIT_STACK, &rlim); 196 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 197 else st->print("%uk", rlim.rlim_cur >> 10); 198 199 st->print(", CORE "); 200 getrlimit(RLIMIT_CORE, &rlim); 201 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 202 else st->print("%uk", rlim.rlim_cur >> 10); 203 204 // Isn't there on solaris 205 #if !defined(TARGET_OS_FAMILY_solaris) && !defined(TARGET_OS_FAMILY_aix) 206 st->print(", NPROC "); 207 getrlimit(RLIMIT_NPROC, &rlim); 208 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 209 else st->print("%d", rlim.rlim_cur); 210 #endif 211 212 st->print(", NOFILE "); 213 getrlimit(RLIMIT_NOFILE, &rlim); 214 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 215 else st->print("%d", rlim.rlim_cur); 216 217 st->print(", AS "); 218 getrlimit(RLIMIT_AS, &rlim); 219 if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity"); 220 else st->print("%uk", rlim.rlim_cur >> 10); 221 st->cr(); 222 } 223 224 void os::Posix::print_uname_info(outputStream* st) { 225 // kernel 226 st->print("uname:"); 227 struct utsname name; 228 uname(&name); 229 st->print("%s ", name.sysname); 230 #ifdef ASSERT 231 st->print("%s ", name.nodename); 232 #endif 233 st->print("%s ", name.release); 234 st->print("%s ", name.version); 235 st->print("%s", name.machine); 236 st->cr(); 237 } 238 239 #ifndef PRODUCT 240 bool os::get_host_name(char* buf, size_t buflen) { 241 struct utsname name; 242 uname(&name); 243 jio_snprintf(buf, buflen, "%s", name.nodename); 244 return true; 245 } 246 #endif // PRODUCT 247 248 bool os::has_allocatable_memory_limit(julong* limit) { 249 struct rlimit rlim; 250 int getrlimit_res = getrlimit(RLIMIT_AS, &rlim); 251 // if there was an error when calling getrlimit, assume that there is no limitation 252 // on virtual memory. 253 bool result; 254 if ((getrlimit_res != 0) || (rlim.rlim_cur == RLIM_INFINITY)) { 255 result = false; 256 } else { 257 *limit = (julong)rlim.rlim_cur; 258 result = true; 259 } 260 #ifdef _LP64 261 return result; 262 #else 263 // arbitrary virtual space limit for 32 bit Unices found by testing. If 264 // getrlimit above returned a limit, bound it with this limit. Otherwise 265 // directly use it. 266 const julong max_virtual_limit = (julong)3800*M; 267 if (result) { 268 *limit = MIN2(*limit, max_virtual_limit); 269 } else { 270 *limit = max_virtual_limit; 271 } 272 273 // bound by actually allocatable memory. The algorithm uses two bounds, an 274 // upper and a lower limit. The upper limit is the current highest amount of 275 // memory that could not be allocated, the lower limit is the current highest 276 // amount of memory that could be allocated. 277 // The algorithm iteratively refines the result by halving the difference 278 // between these limits, updating either the upper limit (if that value could 279 // not be allocated) or the lower limit (if the that value could be allocated) 280 // until the difference between these limits is "small". 281 282 // the minimum amount of memory we care about allocating. 283 const julong min_allocation_size = M; 284 285 julong upper_limit = *limit; 286 287 // first check a few trivial cases 288 if (is_allocatable(upper_limit) || (upper_limit <= min_allocation_size)) { 289 *limit = upper_limit; 290 } else if (!is_allocatable(min_allocation_size)) { 291 // we found that not even min_allocation_size is allocatable. Return it 292 // anyway. There is no point to search for a better value any more. 293 *limit = min_allocation_size; 294 } else { 295 // perform the binary search. 296 julong lower_limit = min_allocation_size; 297 while ((upper_limit - lower_limit) > min_allocation_size) { 298 julong temp_limit = ((upper_limit - lower_limit) / 2) + lower_limit; 299 temp_limit = align_size_down_(temp_limit, min_allocation_size); 300 if (is_allocatable(temp_limit)) { 301 lower_limit = temp_limit; 302 } else { 303 upper_limit = temp_limit; 304 } 305 } 306 *limit = lower_limit; 307 } 308 return true; 309 #endif 310 } 311 312 const char* os::get_current_directory(char *buf, size_t buflen) { 313 return getcwd(buf, buflen); 314 } 315 316 FILE* os::open(int fd, const char* mode) { 317 return ::fdopen(fd, mode); 318 } 319 320 // Builds a platform dependent Agent_OnLoad_<lib_name> function name 321 // which is used to find statically linked in agents. 322 // Parameters: 323 // sym_name: Symbol in library we are looking for 324 // lib_name: Name of library to look in, NULL for shared libs. 325 // is_absolute_path == true if lib_name is absolute path to agent 326 // such as "/a/b/libL.so" 327 // == false if only the base name of the library is passed in 328 // such as "L" 329 char* os::build_agent_function_name(const char *sym_name, const char *lib_name, 330 bool is_absolute_path) { 331 char *agent_entry_name; 332 size_t len; 333 size_t name_len; 334 size_t prefix_len = strlen(JNI_LIB_PREFIX); 335 size_t suffix_len = strlen(JNI_LIB_SUFFIX); 336 const char *start; 337 338 if (lib_name != NULL) { 339 len = name_len = strlen(lib_name); 340 if (is_absolute_path) { 341 // Need to strip path, prefix and suffix 342 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) { 343 lib_name = ++start; 344 } 345 if (len <= (prefix_len + suffix_len)) { 346 return NULL; 347 } 348 lib_name += prefix_len; 349 name_len = strlen(lib_name) - suffix_len; 350 } 351 } 352 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2; 353 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread); 354 if (agent_entry_name == NULL) { 355 return NULL; 356 } 357 strcpy(agent_entry_name, sym_name); 358 if (lib_name != NULL) { 359 strcat(agent_entry_name, "_"); 360 strncat(agent_entry_name, lib_name, name_len); 361 } 362 return agent_entry_name; 363 } 364 365 int os::sleep(Thread* thread, jlong millis, bool interruptible) { 366 assert(thread == Thread::current(), "thread consistency check"); 367 368 ParkEvent * const slp = thread->_SleepEvent ; 369 slp->reset() ; 370 OrderAccess::fence() ; 371 372 if (interruptible) { 373 jlong prevtime = javaTimeNanos(); 374 375 for (;;) { 376 if (os::is_interrupted(thread, true)) { 377 return OS_INTRPT; 378 } 379 380 jlong newtime = javaTimeNanos(); 381 382 if (newtime - prevtime < 0) { 383 // time moving backwards, should only happen if no monotonic clock 384 // not a guarantee() because JVM should not abort on kernel/glibc bugs 385 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected in os::sleep(interruptible)"); 386 } else { 387 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 388 } 389 390 if (millis <= 0) { 391 return OS_OK; 392 } 393 394 prevtime = newtime; 395 396 { 397 assert(thread->is_Java_thread(), "sanity check"); 398 JavaThread *jt = (JavaThread *) thread; 399 ThreadBlockInVM tbivm(jt); 400 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */); 401 402 jt->set_suspend_equivalent(); 403 // cleared by handle_special_suspend_equivalent_condition() or 404 // java_suspend_self() via check_and_wait_while_suspended() 405 406 slp->park(millis); 407 408 // were we externally suspended while we were waiting? 409 jt->check_and_wait_while_suspended(); 410 } 411 } 412 } else { 413 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); 414 jlong prevtime = javaTimeNanos(); 415 416 for (;;) { 417 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on 418 // the 1st iteration ... 419 jlong newtime = javaTimeNanos(); 420 421 if (newtime - prevtime < 0) { 422 // time moving backwards, should only happen if no monotonic clock 423 // not a guarantee() because JVM should not abort on kernel/glibc bugs 424 assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected on os::sleep(!interruptible)"); 425 } else { 426 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC; 427 } 428 429 if (millis <= 0) break ; 430 431 prevtime = newtime; 432 slp->park(millis); 433 } 434 return OS_OK ; 435 } 436 } 437 438 //////////////////////////////////////////////////////////////////////////////// 439 // interrupt support 440 441 void os::interrupt(Thread* thread) { 442 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 443 "possibility of dangling Thread pointer"); 444 445 OSThread* osthread = thread->osthread(); 446 447 if (!osthread->interrupted()) { 448 osthread->set_interrupted(true); 449 // More than one thread can get here with the same value of osthread, 450 // resulting in multiple notifications. We do, however, want the store 451 // to interrupted() to be visible to other threads before we execute unpark(). 452 OrderAccess::fence(); 453 ParkEvent * const slp = thread->_SleepEvent ; 454 if (slp != NULL) slp->unpark() ; 455 } 456 457 // For JSR166. Unpark even if interrupt status already was set 458 if (thread->is_Java_thread()) 459 ((JavaThread*)thread)->parker()->unpark(); 460 461 ParkEvent * ev = thread->_ParkEvent ; 462 if (ev != NULL) ev->unpark() ; 463 464 } 465 466 bool os::is_interrupted(Thread* thread, bool clear_interrupted) { 467 assert(Thread::current() == thread || Threads_lock->owned_by_self(), 468 "possibility of dangling Thread pointer"); 469 470 OSThread* osthread = thread->osthread(); 471 472 bool interrupted = osthread->interrupted(); 473 474 // NOTE that since there is no "lock" around the interrupt and 475 // is_interrupted operations, there is the possibility that the 476 // interrupted flag (in osThread) will be "false" but that the 477 // low-level events will be in the signaled state. This is 478 // intentional. The effect of this is that Object.wait() and 479 // LockSupport.park() will appear to have a spurious wakeup, which 480 // is allowed and not harmful, and the possibility is so rare that 481 // it is not worth the added complexity to add yet another lock. 482 // For the sleep event an explicit reset is performed on entry 483 // to os::sleep, so there is no early return. It has also been 484 // recommended not to put the interrupted flag into the "event" 485 // structure because it hides the issue. 486 if (interrupted && clear_interrupted) { 487 osthread->set_interrupted(false); 488 // consider thread->_SleepEvent->reset() ... optional optimization 489 } 490 491 return interrupted; 492 } 493 494 // Returned string is a constant. For unknown signals "UNKNOWN" is returned. 495 const char* os::Posix::get_signal_name(int sig, char* out, size_t outlen) { 496 497 static const struct { 498 int sig; const char* name; 499 } 500 info[] = 501 { 502 { SIGABRT, "SIGABRT" }, 503 #ifdef SIGAIO 504 { SIGAIO, "SIGAIO" }, 505 #endif 506 { SIGALRM, "SIGALRM" }, 507 #ifdef SIGALRM1 508 { SIGALRM1, "SIGALRM1" }, 509 #endif 510 { SIGBUS, "SIGBUS" }, 511 #ifdef SIGCANCEL 512 { SIGCANCEL, "SIGCANCEL" }, 513 #endif 514 { SIGCHLD, "SIGCHLD" }, 515 #ifdef SIGCLD 516 { SIGCLD, "SIGCLD" }, 517 #endif 518 { SIGCONT, "SIGCONT" }, 519 #ifdef SIGCPUFAIL 520 { SIGCPUFAIL, "SIGCPUFAIL" }, 521 #endif 522 #ifdef SIGDANGER 523 { SIGDANGER, "SIGDANGER" }, 524 #endif 525 #ifdef SIGDIL 526 { SIGDIL, "SIGDIL" }, 527 #endif 528 #ifdef SIGEMT 529 { SIGEMT, "SIGEMT" }, 530 #endif 531 { SIGFPE, "SIGFPE" }, 532 #ifdef SIGFREEZE 533 { SIGFREEZE, "SIGFREEZE" }, 534 #endif 535 #ifdef SIGGFAULT 536 { SIGGFAULT, "SIGGFAULT" }, 537 #endif 538 #ifdef SIGGRANT 539 { SIGGRANT, "SIGGRANT" }, 540 #endif 541 { SIGHUP, "SIGHUP" }, 542 { SIGILL, "SIGILL" }, 543 { SIGINT, "SIGINT" }, 544 #ifdef SIGIO 545 { SIGIO, "SIGIO" }, 546 #endif 547 #ifdef SIGIOINT 548 { SIGIOINT, "SIGIOINT" }, 549 #endif 550 #ifdef SIGIOT 551 // SIGIOT is there for BSD compatibility, but on most Unices just a 552 // synonym for SIGABRT. The result should be "SIGABRT", not 553 // "SIGIOT". 554 #if (SIGIOT != SIGABRT ) 555 { SIGIOT, "SIGIOT" }, 556 #endif 557 #endif 558 #ifdef SIGKAP 559 { SIGKAP, "SIGKAP" }, 560 #endif 561 { SIGKILL, "SIGKILL" }, 562 #ifdef SIGLOST 563 { SIGLOST, "SIGLOST" }, 564 #endif 565 #ifdef SIGLWP 566 { SIGLWP, "SIGLWP" }, 567 #endif 568 #ifdef SIGLWPTIMER 569 { SIGLWPTIMER, "SIGLWPTIMER" }, 570 #endif 571 #ifdef SIGMIGRATE 572 { SIGMIGRATE, "SIGMIGRATE" }, 573 #endif 574 #ifdef SIGMSG 575 { SIGMSG, "SIGMSG" }, 576 #endif 577 { SIGPIPE, "SIGPIPE" }, 578 #ifdef SIGPOLL 579 { SIGPOLL, "SIGPOLL" }, 580 #endif 581 #ifdef SIGPRE 582 { SIGPRE, "SIGPRE" }, 583 #endif 584 { SIGPROF, "SIGPROF" }, 585 #ifdef SIGPTY 586 { SIGPTY, "SIGPTY" }, 587 #endif 588 #ifdef SIGPWR 589 { SIGPWR, "SIGPWR" }, 590 #endif 591 { SIGQUIT, "SIGQUIT" }, 592 #ifdef SIGRECONFIG 593 { SIGRECONFIG, "SIGRECONFIG" }, 594 #endif 595 #ifdef SIGRECOVERY 596 { SIGRECOVERY, "SIGRECOVERY" }, 597 #endif 598 #ifdef SIGRESERVE 599 { SIGRESERVE, "SIGRESERVE" }, 600 #endif 601 #ifdef SIGRETRACT 602 { SIGRETRACT, "SIGRETRACT" }, 603 #endif 604 #ifdef SIGSAK 605 { SIGSAK, "SIGSAK" }, 606 #endif 607 { SIGSEGV, "SIGSEGV" }, 608 #ifdef SIGSOUND 609 { SIGSOUND, "SIGSOUND" }, 610 #endif 611 { SIGSTOP, "SIGSTOP" }, 612 { SIGSYS, "SIGSYS" }, 613 #ifdef SIGSYSERROR 614 { SIGSYSERROR, "SIGSYSERROR" }, 615 #endif 616 #ifdef SIGTALRM 617 { SIGTALRM, "SIGTALRM" }, 618 #endif 619 { SIGTERM, "SIGTERM" }, 620 #ifdef SIGTHAW 621 { SIGTHAW, "SIGTHAW" }, 622 #endif 623 { SIGTRAP, "SIGTRAP" }, 624 #ifdef SIGTSTP 625 { SIGTSTP, "SIGTSTP" }, 626 #endif 627 { SIGTTIN, "SIGTTIN" }, 628 { SIGTTOU, "SIGTTOU" }, 629 #ifdef SIGURG 630 { SIGURG, "SIGURG" }, 631 #endif 632 { SIGUSR1, "SIGUSR1" }, 633 { SIGUSR2, "SIGUSR2" }, 634 #ifdef SIGVIRT 635 { SIGVIRT, "SIGVIRT" }, 636 #endif 637 { SIGVTALRM, "SIGVTALRM" }, 638 #ifdef SIGWAITING 639 { SIGWAITING, "SIGWAITING" }, 640 #endif 641 #ifdef SIGWINCH 642 { SIGWINCH, "SIGWINCH" }, 643 #endif 644 #ifdef SIGWINDOW 645 { SIGWINDOW, "SIGWINDOW" }, 646 #endif 647 { SIGXCPU, "SIGXCPU" }, 648 { SIGXFSZ, "SIGXFSZ" }, 649 #ifdef SIGXRES 650 { SIGXRES, "SIGXRES" }, 651 #endif 652 { -1, NULL } 653 }; 654 655 const char* ret = NULL; 656 657 #ifdef SIGRTMIN 658 if (sig >= SIGRTMIN && sig <= SIGRTMAX) { 659 if (sig == SIGRTMIN) { 660 ret = "SIGRTMIN"; 661 } else if (sig == SIGRTMAX) { 662 ret = "SIGRTMAX"; 663 } else { 664 jio_snprintf(out, outlen, "SIGRTMIN+%d", sig - SIGRTMIN); 665 return out; 666 } 667 } 668 #endif 669 670 if (sig > 0) { 671 for (int idx = 0; info[idx].sig != -1; idx ++) { 672 if (info[idx].sig == sig) { 673 ret = info[idx].name; 674 break; 675 } 676 } 677 } 678 679 if (!ret) { 680 if (!is_valid_signal(sig)) { 681 ret = "INVALID"; 682 } else { 683 ret = "UNKNOWN"; 684 } 685 } 686 687 if (out && outlen > 0) { 688 strncpy(out, ret, outlen); 689 out[outlen - 1] = '\0'; 690 } 691 return out; 692 } 693 694 // Returns true if signal number is valid. 695 bool os::Posix::is_valid_signal(int sig) { 696 // MacOS not really POSIX compliant: sigaddset does not return 697 // an error for invalid signal numbers. However, MacOS does not 698 // support real time signals and simply seems to have just 33 699 // signals with no holes in the signal range. 700 #ifdef __APPLE__ 701 return sig >= 1 && sig < NSIG; 702 #else 703 // Use sigaddset to check for signal validity. 704 sigset_t set; 705 if (sigaddset(&set, sig) == -1 && errno == EINVAL) { 706 return false; 707 } 708 return true; 709 #endif 710 } 711 712 #define NUM_IMPORTANT_SIGS 32 713 // Returns one-line short description of a signal set in a user provided buffer. 714 const char* os::Posix::describe_signal_set_short(const sigset_t* set, char* buffer, size_t buf_size) { 715 assert(buf_size == (NUM_IMPORTANT_SIGS + 1), "wrong buffer size"); 716 // Note: for shortness, just print out the first 32. That should 717 // cover most of the useful ones, apart from realtime signals. 718 for (int sig = 1; sig <= NUM_IMPORTANT_SIGS; sig++) { 719 const int rc = sigismember(set, sig); 720 if (rc == -1 && errno == EINVAL) { 721 buffer[sig-1] = '?'; 722 } else { 723 buffer[sig-1] = rc == 0 ? '0' : '1'; 724 } 725 } 726 buffer[NUM_IMPORTANT_SIGS] = 0; 727 return buffer; 728 } 729 730 // Prints one-line description of a signal set. 731 void os::Posix::print_signal_set_short(outputStream* st, const sigset_t* set) { 732 char buf[NUM_IMPORTANT_SIGS + 1]; 733 os::Posix::describe_signal_set_short(set, buf, sizeof(buf)); 734 st->print("%s", buf); 735 } 736 737 // Writes one-line description of a combination of sigaction.sa_flags into a user 738 // provided buffer. Returns that buffer. 739 const char* os::Posix::describe_sa_flags(int flags, char* buffer, size_t size) { 740 char* p = buffer; 741 size_t remaining = size; 742 bool first = true; 743 int idx = 0; 744 745 assert(buffer, "invalid argument"); 746 747 if (size == 0) { 748 return buffer; 749 } 750 751 strncpy(buffer, "none", size); 752 753 const struct { 754 int i; 755 const char* s; 756 } flaginfo [] = { 757 { SA_NOCLDSTOP, "SA_NOCLDSTOP" }, 758 { SA_ONSTACK, "SA_ONSTACK" }, 759 { SA_RESETHAND, "SA_RESETHAND" }, 760 { SA_RESTART, "SA_RESTART" }, 761 { SA_SIGINFO, "SA_SIGINFO" }, 762 { SA_NOCLDWAIT, "SA_NOCLDWAIT" }, 763 { SA_NODEFER, "SA_NODEFER" }, 764 #ifdef AIX 765 { SA_ONSTACK, "SA_ONSTACK" }, 766 { SA_OLDSTYLE, "SA_OLDSTYLE" }, 767 #endif 768 { 0, NULL } 769 }; 770 771 for (idx = 0; flaginfo[idx].s && remaining > 1; idx++) { 772 if (flags & flaginfo[idx].i) { 773 if (first) { 774 jio_snprintf(p, remaining, "%s", flaginfo[idx].s); 775 first = false; 776 } else { 777 jio_snprintf(p, remaining, "|%s", flaginfo[idx].s); 778 } 779 const size_t len = strlen(p); 780 p += len; 781 remaining -= len; 782 } 783 } 784 785 buffer[size - 1] = '\0'; 786 787 return buffer; 788 } 789 790 // Prints one-line description of a combination of sigaction.sa_flags. 791 void os::Posix::print_sa_flags(outputStream* st, int flags) { 792 char buffer[0x100]; 793 os::Posix::describe_sa_flags(flags, buffer, sizeof(buffer)); 794 st->print("%s", buffer); 795 } 796 797 // Helper function for os::Posix::print_siginfo_...(): 798 // return a textual description for signal code. 799 struct enum_sigcode_desc_t { 800 const char* s_name; 801 const char* s_desc; 802 }; 803 804 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) { 805 806 const struct { 807 int sig; int code; const char* s_code; const char* s_desc; 808 } t1 [] = { 809 { SIGILL, ILL_ILLOPC, "ILL_ILLOPC", "Illegal opcode." }, 810 { SIGILL, ILL_ILLOPN, "ILL_ILLOPN", "Illegal operand." }, 811 { SIGILL, ILL_ILLADR, "ILL_ILLADR", "Illegal addressing mode." }, 812 { SIGILL, ILL_ILLTRP, "ILL_ILLTRP", "Illegal trap." }, 813 { SIGILL, ILL_PRVOPC, "ILL_PRVOPC", "Privileged opcode." }, 814 { SIGILL, ILL_PRVREG, "ILL_PRVREG", "Privileged register." }, 815 { SIGILL, ILL_COPROC, "ILL_COPROC", "Coprocessor error." }, 816 { SIGILL, ILL_BADSTK, "ILL_BADSTK", "Internal stack error." }, 817 #if defined(IA64) && defined(LINUX) 818 { SIGILL, ILL_BADIADDR, "ILL_BADIADDR", "Unimplemented instruction address" }, 819 { SIGILL, ILL_BREAK, "ILL_BREAK", "Application Break instruction" }, 820 #endif 821 { SIGFPE, FPE_INTDIV, "FPE_INTDIV", "Integer divide by zero." }, 822 { SIGFPE, FPE_INTOVF, "FPE_INTOVF", "Integer overflow." }, 823 { SIGFPE, FPE_FLTDIV, "FPE_FLTDIV", "Floating-point divide by zero." }, 824 { SIGFPE, FPE_FLTOVF, "FPE_FLTOVF", "Floating-point overflow." }, 825 { SIGFPE, FPE_FLTUND, "FPE_FLTUND", "Floating-point underflow." }, 826 { SIGFPE, FPE_FLTRES, "FPE_FLTRES", "Floating-point inexact result." }, 827 { SIGFPE, FPE_FLTINV, "FPE_FLTINV", "Invalid floating-point operation." }, 828 { SIGFPE, FPE_FLTSUB, "FPE_FLTSUB", "Subscript out of range." }, 829 { SIGSEGV, SEGV_MAPERR, "SEGV_MAPERR", "Address not mapped to object." }, 830 { SIGSEGV, SEGV_ACCERR, "SEGV_ACCERR", "Invalid permissions for mapped object." }, 831 #ifdef AIX 832 // no explanation found what keyerr would be 833 { SIGSEGV, SEGV_KEYERR, "SEGV_KEYERR", "key error" }, 834 #endif 835 #if defined(IA64) && !defined(AIX) 836 { SIGSEGV, SEGV_PSTKOVF, "SEGV_PSTKOVF", "Paragraph stack overflow" }, 837 #endif 838 { SIGBUS, BUS_ADRALN, "BUS_ADRALN", "Invalid address alignment." }, 839 { SIGBUS, BUS_ADRERR, "BUS_ADRERR", "Nonexistent physical address." }, 840 { SIGBUS, BUS_OBJERR, "BUS_OBJERR", "Object-specific hardware error." }, 841 { SIGTRAP, TRAP_BRKPT, "TRAP_BRKPT", "Process breakpoint." }, 842 { SIGTRAP, TRAP_TRACE, "TRAP_TRACE", "Process trace trap." }, 843 { SIGCHLD, CLD_EXITED, "CLD_EXITED", "Child has exited." }, 844 { SIGCHLD, CLD_KILLED, "CLD_KILLED", "Child has terminated abnormally and did not create a core file." }, 845 { SIGCHLD, CLD_DUMPED, "CLD_DUMPED", "Child has terminated abnormally and created a core file." }, 846 { SIGCHLD, CLD_TRAPPED, "CLD_TRAPPED", "Traced child has trapped." }, 847 { SIGCHLD, CLD_STOPPED, "CLD_STOPPED", "Child has stopped." }, 848 { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." }, 849 #ifdef SIGPOLL 850 { SIGPOLL, POLL_OUT, "POLL_OUT", "Output buffers available." }, 851 { SIGPOLL, POLL_MSG, "POLL_MSG", "Input message available." }, 852 { SIGPOLL, POLL_ERR, "POLL_ERR", "I/O error." }, 853 { SIGPOLL, POLL_PRI, "POLL_PRI", "High priority input available." }, 854 { SIGPOLL, POLL_HUP, "POLL_HUP", "Device disconnected. [Option End]" }, 855 #endif 856 { -1, -1, NULL, NULL } 857 }; 858 859 // Codes valid in any signal context. 860 const struct { 861 int code; const char* s_code; const char* s_desc; 862 } t2 [] = { 863 { SI_USER, "SI_USER", "Signal sent by kill()." }, 864 { SI_QUEUE, "SI_QUEUE", "Signal sent by the sigqueue()." }, 865 { SI_TIMER, "SI_TIMER", "Signal generated by expiration of a timer set by timer_settime()." }, 866 { SI_ASYNCIO, "SI_ASYNCIO", "Signal generated by completion of an asynchronous I/O request." }, 867 { SI_MESGQ, "SI_MESGQ", "Signal generated by arrival of a message on an empty message queue." }, 868 // Linux specific 869 #ifdef SI_TKILL 870 { SI_TKILL, "SI_TKILL", "Signal sent by tkill (pthread_kill)" }, 871 #endif 872 #ifdef SI_DETHREAD 873 { SI_DETHREAD, "SI_DETHREAD", "Signal sent by execve() killing subsidiary threads" }, 874 #endif 875 #ifdef SI_KERNEL 876 { SI_KERNEL, "SI_KERNEL", "Signal sent by kernel." }, 877 #endif 878 #ifdef SI_SIGIO 879 { SI_SIGIO, "SI_SIGIO", "Signal sent by queued SIGIO" }, 880 #endif 881 882 #ifdef AIX 883 { SI_UNDEFINED, "SI_UNDEFINED","siginfo contains partial information" }, 884 { SI_EMPTY, "SI_EMPTY", "siginfo contains no useful information" }, 885 #endif 886 887 #ifdef __sun 888 { SI_NOINFO, "SI_NOINFO", "No signal information" }, 889 { SI_RCTL, "SI_RCTL", "kernel generated signal via rctl action" }, 890 { SI_LWP, "SI_LWP", "Signal sent via lwp_kill" }, 891 #endif 892 893 { -1, NULL, NULL } 894 }; 895 896 const char* s_code = NULL; 897 const char* s_desc = NULL; 898 899 for (int i = 0; t1[i].sig != -1; i ++) { 900 if (t1[i].sig == si->si_signo && t1[i].code == si->si_code) { 901 s_code = t1[i].s_code; 902 s_desc = t1[i].s_desc; 903 break; 904 } 905 } 906 907 if (s_code == NULL) { 908 for (int i = 0; t2[i].s_code != NULL; i ++) { 909 if (t2[i].code == si->si_code) { 910 s_code = t2[i].s_code; 911 s_desc = t2[i].s_desc; 912 } 913 } 914 } 915 916 if (s_code == NULL) { 917 out->s_name = "unknown"; 918 out->s_desc = "unknown"; 919 return false; 920 } 921 922 out->s_name = s_code; 923 out->s_desc = s_desc; 924 925 return true; 926 } 927 928 // A POSIX conform, platform-independend siginfo print routine. 929 // Short print out on one line. 930 void os::Posix::print_siginfo_brief(outputStream* os, const siginfo_t* si) { 931 char buf[20]; 932 os->print("siginfo: "); 933 934 if (!si) { 935 os->print("<null>"); 936 return; 937 } 938 939 // See print_siginfo_full() for details. 940 const int sig = si->si_signo; 941 942 os->print("si_signo: %d (%s)", sig, os::Posix::get_signal_name(sig, buf, sizeof(buf))); 943 944 enum_sigcode_desc_t ed; 945 if (get_signal_code_description(si, &ed)) { 946 os->print(", si_code: %d (%s)", si->si_code, ed.s_name); 947 } else { 948 os->print(", si_code: %d (unknown)", si->si_code); 949 } 950 951 if (si->si_errno) { 952 os->print(", si_errno: %d", si->si_errno); 953 } 954 955 const int me = (int) ::getpid(); 956 const int pid = (int) si->si_pid; 957 958 if (si->si_code == SI_USER || si->si_code == SI_QUEUE) { 959 if (IS_VALID_PID(pid) && pid != me) { 960 os->print(", sent from pid: %d (uid: %d)", pid, (int) si->si_uid); 961 } 962 } else if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || 963 sig == SIGTRAP || sig == SIGFPE) { 964 os->print(", si_addr: " PTR_FORMAT, si->si_addr); 965 #ifdef SIGPOLL 966 } else if (sig == SIGPOLL) { 967 os->print(", si_band: " PTR64_FORMAT, (uint64_t)si->si_band); 968 #endif 969 } else if (sig == SIGCHLD) { 970 os->print_cr(", si_pid: %d, si_uid: %d, si_status: %d", (int) si->si_pid, si->si_uid, si->si_status); 971 } 972 } 973 974 os::WatcherThreadCrashProtection::WatcherThreadCrashProtection() { 975 assert(Thread::current()->is_Watcher_thread(), "Must be WatcherThread"); 976 } 977 978 /* 979 * See the caveats for this class in os_posix.hpp 980 * Protects the callback call so that SIGSEGV / SIGBUS jumps back into this 981 * method and returns false. If none of the signals are raised, returns true. 982 * The callback is supposed to provide the method that should be protected. 983 */ 984 bool os::WatcherThreadCrashProtection::call(os::CrashProtectionCallback& cb) { 985 sigset_t saved_sig_mask; 986 987 assert(Thread::current()->is_Watcher_thread(), "Only for WatcherThread"); 988 assert(!WatcherThread::watcher_thread()->has_crash_protection(), 989 "crash_protection already set?"); 990 991 // we cannot rely on sigsetjmp/siglongjmp to save/restore the signal mask 992 // since on at least some systems (OS X) siglongjmp will restore the mask 993 // for the process, not the thread 994 pthread_sigmask(0, NULL, &saved_sig_mask); 995 if (sigsetjmp(_jmpbuf, 0) == 0) { 996 // make sure we can see in the signal handler that we have crash protection 997 // installed 998 WatcherThread::watcher_thread()->set_crash_protection(this); 999 cb.call(); 1000 // and clear the crash protection 1001 WatcherThread::watcher_thread()->set_crash_protection(NULL); 1002 return true; 1003 } 1004 // this happens when we siglongjmp() back 1005 pthread_sigmask(SIG_SETMASK, &saved_sig_mask, NULL); 1006 WatcherThread::watcher_thread()->set_crash_protection(NULL); 1007 return false; 1008 } 1009 1010 void os::WatcherThreadCrashProtection::restore() { 1011 assert(WatcherThread::watcher_thread()->has_crash_protection(), 1012 "must have crash protection"); 1013 1014 siglongjmp(_jmpbuf, 1); 1015 } 1016 1017 void os::WatcherThreadCrashProtection::check_crash_protection(int sig, 1018 Thread* thread) { 1019 1020 if (thread != NULL && 1021 thread->is_Watcher_thread() && 1022 WatcherThread::watcher_thread()->has_crash_protection()) { 1023 1024 if (sig == SIGSEGV || sig == SIGBUS) { 1025 WatcherThread::watcher_thread()->crash_protection()->restore(); 1026 } 1027 } 1028 } 1029 1030 #define check_with_errno(check_type, cond, msg) \ 1031 do { \ 1032 int err = errno; \ 1033 check_type(cond, err_msg("%s; error='%s' (errno=%d)", msg, strerror(err), err)); \ 1034 } while (false) 1035 1036 #define assert_with_errno(cond, msg) check_with_errno(assert, cond, msg) 1037 #define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg) 1038 1039 // POSIX unamed semaphores are not supported on OS X. 1040 #ifndef __APPLE__ 1041 1042 PosixSemaphore::PosixSemaphore(uint value) { 1043 int ret = sem_init(&_semaphore, 0, value); 1044 1045 guarantee_with_errno(ret == 0, "Failed to initialize semaphore"); 1046 } 1047 1048 PosixSemaphore::~PosixSemaphore() { 1049 sem_destroy(&_semaphore); 1050 } 1051 1052 void PosixSemaphore::signal(uint count) { 1053 for (uint i = 0; i < count; i++) { 1054 int ret = sem_post(&_semaphore); 1055 1056 assert_with_errno(ret == 0, "sem_post failed"); 1057 } 1058 } 1059 1060 void PosixSemaphore::wait() { 1061 int ret; 1062 1063 do { 1064 ret = sem_wait(&_semaphore); 1065 } while (ret != 0 && errno == EINTR); 1066 1067 assert_with_errno(ret == 0, "sem_wait failed"); 1068 } 1069 1070 bool PosixSemaphore::trywait() { 1071 int ret; 1072 1073 do { 1074 ret = sem_trywait(&_semaphore); 1075 } while (ret != 0 && errno == EINTR); 1076 1077 assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed"); 1078 1079 return ret == 0; 1080 } 1081 1082 bool PosixSemaphore::timedwait(struct timespec ts) { 1083 while (true) { 1084 int result = sem_timedwait(&_semaphore, &ts); 1085 if (result == 0) { 1086 return true; 1087 } else if (errno == EINTR) { 1088 continue; 1089 } else if (errno == ETIMEDOUT) { 1090 return false; 1091 } else { 1092 assert_with_errno(false, "timedwait failed"); 1093 return false; 1094 } 1095 } 1096 } 1097 1098 #endif // __APPLE__