rev 12346 : 8169373: Work around linux NPTL stack guard error.
Summary: Also skip libc guard page for compiler thread, merge similar code on linux platforms, and streamline libc guard page handling on linuxs390, linuxppc, aixppc.
Reviewed-by: dholmes, dcubed

   1 /*
   2  * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #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/macros.hpp"
  32 #include "utilities/vmError.hpp"
  33 
  34 #include <signal.h>
  35 #include <unistd.h>
  36 #include <sys/resource.h>
  37 #include <sys/utsname.h>
  38 #include <pthread.h>
  39 #include <semaphore.h>
  40 #include <signal.h>
  41 
  42 // Todo: provide a os::get_max_process_id() or similar. Number of processes
  43 // may have been configured, can be read more accurately from proc fs etc.
  44 #ifndef MAX_PID
  45 #define MAX_PID INT_MAX
  46 #endif
  47 #define IS_VALID_PID(p) (p > 0 && p < MAX_PID)
  48 
  49 // Check core dump limit and report possible place where core can be found
  50 void os::check_dump_limit(char* buffer, size_t bufferSize) {
  51   if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && !CreateCoredumpOnCrash) {
  52     jio_snprintf(buffer, bufferSize, "CreateCoredumpOnCrash is disabled from command line");
  53     VMError::record_coredump_status(buffer, false);
  54     return;
  55   }
  56 
  57   int n;
  58   struct rlimit rlim;
  59   bool success;
  60 
  61   char core_path[PATH_MAX];
  62   n = get_core_path(core_path, PATH_MAX);
  63 
  64   if (n <= 0) {
  65     jio_snprintf(buffer, bufferSize, "core.%d (may not exist)", current_process_id());
  66     success = true;
  67 #ifdef LINUX
  68   } else if (core_path[0] == '"') { // redirect to user process
  69     jio_snprintf(buffer, bufferSize, "Core dumps may be processed with %s", core_path);
  70     success = true;
  71 #endif
  72   } else if (getrlimit(RLIMIT_CORE, &rlim) != 0) {
  73     jio_snprintf(buffer, bufferSize, "%s (may not exist)", core_path);
  74     success = true;
  75   } else {
  76     switch(rlim.rlim_cur) {
  77       case RLIM_INFINITY:
  78         jio_snprintf(buffer, bufferSize, "%s", core_path);
  79         success = true;
  80         break;
  81       case 0:
  82         jio_snprintf(buffer, bufferSize, "Core dumps have been disabled. To enable core dumping, try \"ulimit -c unlimited\" before starting Java again");
  83         success = false;
  84         break;
  85       default:
  86         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));
  87         success = true;
  88         break;
  89     }
  90   }
  91 
  92   VMError::record_coredump_status(buffer, success);
  93 }
  94 
  95 int os::get_native_stack(address* stack, int frames, int toSkip) {
  96   int frame_idx = 0;
  97   int num_of_frames;  // number of frames captured
  98   frame fr = os::current_frame();
  99   while (fr.pc() && frame_idx < frames) {
 100     if (toSkip > 0) {
 101       toSkip --;
 102     } else {
 103       stack[frame_idx ++] = fr.pc();
 104     }
 105     if (fr.fp() == NULL || fr.cb() != NULL ||
 106         fr.sender_pc() == NULL || os::is_first_C_frame(&fr)) break;
 107 
 108     if (fr.sender_pc() && !os::is_first_C_frame(&fr)) {
 109       fr = os::get_sender_for_C_frame(&fr);
 110     } else {
 111       break;
 112     }
 113   }
 114   num_of_frames = frame_idx;
 115   for (; frame_idx < frames; frame_idx ++) {
 116     stack[frame_idx] = NULL;
 117   }
 118 
 119   return num_of_frames;
 120 }
 121 
 122 
 123 bool os::unsetenv(const char* name) {
 124   assert(name != NULL, "Null pointer");
 125   return (::unsetenv(name) == 0);
 126 }
 127 
 128 int os::get_last_error() {
 129   return errno;
 130 }
 131 
 132 bool os::is_debugger_attached() {
 133   // not implemented
 134   return false;
 135 }
 136 
 137 void os::wait_for_keypress_at_exit(void) {
 138   // don't do anything on posix platforms
 139   return;
 140 }
 141 
 142 // Multiple threads can race in this code, and can remap over each other with MAP_FIXED,
 143 // so on posix, unmap the section at the start and at the end of the chunk that we mapped
 144 // rather than unmapping and remapping the whole chunk to get requested alignment.
 145 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
 146   assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
 147       "Alignment must be a multiple of allocation granularity (page size)");
 148   assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
 149 
 150   size_t extra_size = size + alignment;
 151   assert(extra_size >= size, "overflow, size is too large to allow alignment");
 152 
 153   char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
 154 
 155   if (extra_base == NULL) {
 156     return NULL;
 157   }
 158 
 159   // Do manual alignment
 160   char* aligned_base = (char*) align_size_up((uintptr_t) extra_base, alignment);
 161 
 162   // [  |                                       |  ]
 163   // ^ extra_base
 164   //    ^ extra_base + begin_offset == aligned_base
 165   //     extra_base + begin_offset + size       ^
 166   //                       extra_base + extra_size ^
 167   // |<>| == begin_offset
 168   //                              end_offset == |<>|
 169   size_t begin_offset = aligned_base - extra_base;
 170   size_t end_offset = (extra_base + extra_size) - (aligned_base + size);
 171 
 172   if (begin_offset > 0) {
 173       os::release_memory(extra_base, begin_offset);
 174   }
 175 
 176   if (end_offset > 0) {
 177       os::release_memory(extra_base + begin_offset + size, end_offset);
 178   }
 179 
 180   return aligned_base;
 181 }
 182 
 183 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
 184     return vsnprintf(buf, len, fmt, args);
 185 }
 186 
 187 int os::get_fileno(FILE* fp) {
 188   return NOT_AIX(::)fileno(fp);
 189 }
 190 
 191 struct tm* os::gmtime_pd(const time_t* clock, struct tm*  res) {
 192   return gmtime_r(clock, res);
 193 }
 194 
 195 void os::Posix::print_load_average(outputStream* st) {
 196   st->print("load average:");
 197   double loadavg[3];
 198   os::loadavg(loadavg, 3);
 199   st->print("%0.02f %0.02f %0.02f", loadavg[0], loadavg[1], loadavg[2]);
 200   st->cr();
 201 }
 202 
 203 void os::Posix::print_rlimit_info(outputStream* st) {
 204   st->print("rlimit:");
 205   struct rlimit rlim;
 206 
 207   st->print(" STACK ");
 208   getrlimit(RLIMIT_STACK, &rlim);
 209   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 210   else st->print("%luk", rlim.rlim_cur >> 10);
 211 
 212   st->print(", CORE ");
 213   getrlimit(RLIMIT_CORE, &rlim);
 214   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 215   else st->print("%luk", rlim.rlim_cur >> 10);
 216 
 217   // Isn't there on solaris
 218 #if !defined(SOLARIS) && !defined(AIX)
 219   st->print(", NPROC ");
 220   getrlimit(RLIMIT_NPROC, &rlim);
 221   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 222   else st->print("%lu", rlim.rlim_cur);
 223 #endif
 224 
 225   st->print(", NOFILE ");
 226   getrlimit(RLIMIT_NOFILE, &rlim);
 227   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 228   else st->print("%lu", rlim.rlim_cur);
 229 
 230   st->print(", AS ");
 231   getrlimit(RLIMIT_AS, &rlim);
 232   if (rlim.rlim_cur == RLIM_INFINITY) st->print("infinity");
 233   else st->print("%luk", rlim.rlim_cur >> 10);
 234   st->cr();
 235 }
 236 
 237 void os::Posix::print_uname_info(outputStream* st) {
 238   // kernel
 239   st->print("uname:");
 240   struct utsname name;
 241   uname(&name);
 242   st->print("%s ", name.sysname);
 243 #ifdef ASSERT
 244   st->print("%s ", name.nodename);
 245 #endif
 246   st->print("%s ", name.release);
 247   st->print("%s ", name.version);
 248   st->print("%s", name.machine);
 249   st->cr();
 250 }
 251 
 252 bool os::get_host_name(char* buf, size_t buflen) {
 253   struct utsname name;
 254   uname(&name);
 255   jio_snprintf(buf, buflen, "%s", name.nodename);
 256   return true;
 257 }
 258 
 259 bool os::has_allocatable_memory_limit(julong* limit) {
 260   struct rlimit rlim;
 261   int getrlimit_res = getrlimit(RLIMIT_AS, &rlim);
 262   // if there was an error when calling getrlimit, assume that there is no limitation
 263   // on virtual memory.
 264   bool result;
 265   if ((getrlimit_res != 0) || (rlim.rlim_cur == RLIM_INFINITY)) {
 266     result = false;
 267   } else {
 268     *limit = (julong)rlim.rlim_cur;
 269     result = true;
 270   }
 271 #ifdef _LP64
 272   return result;
 273 #else
 274   // arbitrary virtual space limit for 32 bit Unices found by testing. If
 275   // getrlimit above returned a limit, bound it with this limit. Otherwise
 276   // directly use it.
 277   const julong max_virtual_limit = (julong)3800*M;
 278   if (result) {
 279     *limit = MIN2(*limit, max_virtual_limit);
 280   } else {
 281     *limit = max_virtual_limit;
 282   }
 283 
 284   // bound by actually allocatable memory. The algorithm uses two bounds, an
 285   // upper and a lower limit. The upper limit is the current highest amount of
 286   // memory that could not be allocated, the lower limit is the current highest
 287   // amount of memory that could be allocated.
 288   // The algorithm iteratively refines the result by halving the difference
 289   // between these limits, updating either the upper limit (if that value could
 290   // not be allocated) or the lower limit (if the that value could be allocated)
 291   // until the difference between these limits is "small".
 292 
 293   // the minimum amount of memory we care about allocating.
 294   const julong min_allocation_size = M;
 295 
 296   julong upper_limit = *limit;
 297 
 298   // first check a few trivial cases
 299   if (is_allocatable(upper_limit) || (upper_limit <= min_allocation_size)) {
 300     *limit = upper_limit;
 301   } else if (!is_allocatable(min_allocation_size)) {
 302     // we found that not even min_allocation_size is allocatable. Return it
 303     // anyway. There is no point to search for a better value any more.
 304     *limit = min_allocation_size;
 305   } else {
 306     // perform the binary search.
 307     julong lower_limit = min_allocation_size;
 308     while ((upper_limit - lower_limit) > min_allocation_size) {
 309       julong temp_limit = ((upper_limit - lower_limit) / 2) + lower_limit;
 310       temp_limit = align_size_down_(temp_limit, min_allocation_size);
 311       if (is_allocatable(temp_limit)) {
 312         lower_limit = temp_limit;
 313       } else {
 314         upper_limit = temp_limit;
 315       }
 316     }
 317     *limit = lower_limit;
 318   }
 319   return true;
 320 #endif
 321 }
 322 
 323 const char* os::get_current_directory(char *buf, size_t buflen) {
 324   return getcwd(buf, buflen);
 325 }
 326 
 327 FILE* os::open(int fd, const char* mode) {
 328   return ::fdopen(fd, mode);
 329 }
 330 
 331 void os::flockfile(FILE* fp) {
 332   ::flockfile(fp);
 333 }
 334 
 335 void os::funlockfile(FILE* fp) {
 336   ::funlockfile(fp);
 337 }
 338 
 339 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
 340 // which is used to find statically linked in agents.
 341 // Parameters:
 342 //            sym_name: Symbol in library we are looking for
 343 //            lib_name: Name of library to look in, NULL for shared libs.
 344 //            is_absolute_path == true if lib_name is absolute path to agent
 345 //                                     such as "/a/b/libL.so"
 346 //            == false if only the base name of the library is passed in
 347 //               such as "L"
 348 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
 349                                     bool is_absolute_path) {
 350   char *agent_entry_name;
 351   size_t len;
 352   size_t name_len;
 353   size_t prefix_len = strlen(JNI_LIB_PREFIX);
 354   size_t suffix_len = strlen(JNI_LIB_SUFFIX);
 355   const char *start;
 356 
 357   if (lib_name != NULL) {
 358     name_len = strlen(lib_name);
 359     if (is_absolute_path) {
 360       // Need to strip path, prefix and suffix
 361       if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
 362         lib_name = ++start;
 363       }
 364       if (strlen(lib_name) <= (prefix_len + suffix_len)) {
 365         return NULL;
 366       }
 367       lib_name += prefix_len;
 368       name_len = strlen(lib_name) - suffix_len;
 369     }
 370   }
 371   len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
 372   agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
 373   if (agent_entry_name == NULL) {
 374     return NULL;
 375   }
 376   strcpy(agent_entry_name, sym_name);
 377   if (lib_name != NULL) {
 378     strcat(agent_entry_name, "_");
 379     strncat(agent_entry_name, lib_name, name_len);
 380   }
 381   return agent_entry_name;
 382 }
 383 
 384 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
 385   assert(thread == Thread::current(),  "thread consistency check");
 386 
 387   ParkEvent * const slp = thread->_SleepEvent ;
 388   slp->reset() ;
 389   OrderAccess::fence() ;
 390 
 391   if (interruptible) {
 392     jlong prevtime = javaTimeNanos();
 393 
 394     for (;;) {
 395       if (os::is_interrupted(thread, true)) {
 396         return OS_INTRPT;
 397       }
 398 
 399       jlong newtime = javaTimeNanos();
 400 
 401       if (newtime - prevtime < 0) {
 402         // time moving backwards, should only happen if no monotonic clock
 403         // not a guarantee() because JVM should not abort on kernel/glibc bugs
 404         assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected in os::sleep(interruptible)");
 405       } else {
 406         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
 407       }
 408 
 409       if (millis <= 0) {
 410         return OS_OK;
 411       }
 412 
 413       prevtime = newtime;
 414 
 415       {
 416         assert(thread->is_Java_thread(), "sanity check");
 417         JavaThread *jt = (JavaThread *) thread;
 418         ThreadBlockInVM tbivm(jt);
 419         OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
 420 
 421         jt->set_suspend_equivalent();
 422         // cleared by handle_special_suspend_equivalent_condition() or
 423         // java_suspend_self() via check_and_wait_while_suspended()
 424 
 425         slp->park(millis);
 426 
 427         // were we externally suspended while we were waiting?
 428         jt->check_and_wait_while_suspended();
 429       }
 430     }
 431   } else {
 432     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
 433     jlong prevtime = javaTimeNanos();
 434 
 435     for (;;) {
 436       // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
 437       // the 1st iteration ...
 438       jlong newtime = javaTimeNanos();
 439 
 440       if (newtime - prevtime < 0) {
 441         // time moving backwards, should only happen if no monotonic clock
 442         // not a guarantee() because JVM should not abort on kernel/glibc bugs
 443         assert(!os::supports_monotonic_clock(), "unexpected time moving backwards detected on os::sleep(!interruptible)");
 444       } else {
 445         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
 446       }
 447 
 448       if (millis <= 0) break ;
 449 
 450       prevtime = newtime;
 451       slp->park(millis);
 452     }
 453     return OS_OK ;
 454   }
 455 }
 456 
 457 ////////////////////////////////////////////////////////////////////////////////
 458 // interrupt support
 459 
 460 void os::interrupt(Thread* thread) {
 461   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
 462     "possibility of dangling Thread pointer");
 463 
 464   OSThread* osthread = thread->osthread();
 465 
 466   if (!osthread->interrupted()) {
 467     osthread->set_interrupted(true);
 468     // More than one thread can get here with the same value of osthread,
 469     // resulting in multiple notifications.  We do, however, want the store
 470     // to interrupted() to be visible to other threads before we execute unpark().
 471     OrderAccess::fence();
 472     ParkEvent * const slp = thread->_SleepEvent ;
 473     if (slp != NULL) slp->unpark() ;
 474   }
 475 
 476   // For JSR166. Unpark even if interrupt status already was set
 477   if (thread->is_Java_thread())
 478     ((JavaThread*)thread)->parker()->unpark();
 479 
 480   ParkEvent * ev = thread->_ParkEvent ;
 481   if (ev != NULL) ev->unpark() ;
 482 
 483 }
 484 
 485 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
 486   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
 487     "possibility of dangling Thread pointer");
 488 
 489   OSThread* osthread = thread->osthread();
 490 
 491   bool interrupted = osthread->interrupted();
 492 
 493   // NOTE that since there is no "lock" around the interrupt and
 494   // is_interrupted operations, there is the possibility that the
 495   // interrupted flag (in osThread) will be "false" but that the
 496   // low-level events will be in the signaled state. This is
 497   // intentional. The effect of this is that Object.wait() and
 498   // LockSupport.park() will appear to have a spurious wakeup, which
 499   // is allowed and not harmful, and the possibility is so rare that
 500   // it is not worth the added complexity to add yet another lock.
 501   // For the sleep event an explicit reset is performed on entry
 502   // to os::sleep, so there is no early return. It has also been
 503   // recommended not to put the interrupted flag into the "event"
 504   // structure because it hides the issue.
 505   if (interrupted && clear_interrupted) {
 506     osthread->set_interrupted(false);
 507     // consider thread->_SleepEvent->reset() ... optional optimization
 508   }
 509 
 510   return interrupted;
 511 }
 512 
 513 
 514 
 515 static const struct {
 516   int sig; const char* name;
 517 }
 518  g_signal_info[] =
 519   {
 520   {  SIGABRT,     "SIGABRT" },
 521 #ifdef SIGAIO
 522   {  SIGAIO,      "SIGAIO" },
 523 #endif
 524   {  SIGALRM,     "SIGALRM" },
 525 #ifdef SIGALRM1
 526   {  SIGALRM1,    "SIGALRM1" },
 527 #endif
 528   {  SIGBUS,      "SIGBUS" },
 529 #ifdef SIGCANCEL
 530   {  SIGCANCEL,   "SIGCANCEL" },
 531 #endif
 532   {  SIGCHLD,     "SIGCHLD" },
 533 #ifdef SIGCLD
 534   {  SIGCLD,      "SIGCLD" },
 535 #endif
 536   {  SIGCONT,     "SIGCONT" },
 537 #ifdef SIGCPUFAIL
 538   {  SIGCPUFAIL,  "SIGCPUFAIL" },
 539 #endif
 540 #ifdef SIGDANGER
 541   {  SIGDANGER,   "SIGDANGER" },
 542 #endif
 543 #ifdef SIGDIL
 544   {  SIGDIL,      "SIGDIL" },
 545 #endif
 546 #ifdef SIGEMT
 547   {  SIGEMT,      "SIGEMT" },
 548 #endif
 549   {  SIGFPE,      "SIGFPE" },
 550 #ifdef SIGFREEZE
 551   {  SIGFREEZE,   "SIGFREEZE" },
 552 #endif
 553 #ifdef SIGGFAULT
 554   {  SIGGFAULT,   "SIGGFAULT" },
 555 #endif
 556 #ifdef SIGGRANT
 557   {  SIGGRANT,    "SIGGRANT" },
 558 #endif
 559   {  SIGHUP,      "SIGHUP" },
 560   {  SIGILL,      "SIGILL" },
 561   {  SIGINT,      "SIGINT" },
 562 #ifdef SIGIO
 563   {  SIGIO,       "SIGIO" },
 564 #endif
 565 #ifdef SIGIOINT
 566   {  SIGIOINT,    "SIGIOINT" },
 567 #endif
 568 #ifdef SIGIOT
 569 // SIGIOT is there for BSD compatibility, but on most Unices just a
 570 // synonym for SIGABRT. The result should be "SIGABRT", not
 571 // "SIGIOT".
 572 #if (SIGIOT != SIGABRT )
 573   {  SIGIOT,      "SIGIOT" },
 574 #endif
 575 #endif
 576 #ifdef SIGKAP
 577   {  SIGKAP,      "SIGKAP" },
 578 #endif
 579   {  SIGKILL,     "SIGKILL" },
 580 #ifdef SIGLOST
 581   {  SIGLOST,     "SIGLOST" },
 582 #endif
 583 #ifdef SIGLWP
 584   {  SIGLWP,      "SIGLWP" },
 585 #endif
 586 #ifdef SIGLWPTIMER
 587   {  SIGLWPTIMER, "SIGLWPTIMER" },
 588 #endif
 589 #ifdef SIGMIGRATE
 590   {  SIGMIGRATE,  "SIGMIGRATE" },
 591 #endif
 592 #ifdef SIGMSG
 593   {  SIGMSG,      "SIGMSG" },
 594 #endif
 595   {  SIGPIPE,     "SIGPIPE" },
 596 #ifdef SIGPOLL
 597   {  SIGPOLL,     "SIGPOLL" },
 598 #endif
 599 #ifdef SIGPRE
 600   {  SIGPRE,      "SIGPRE" },
 601 #endif
 602   {  SIGPROF,     "SIGPROF" },
 603 #ifdef SIGPTY
 604   {  SIGPTY,      "SIGPTY" },
 605 #endif
 606 #ifdef SIGPWR
 607   {  SIGPWR,      "SIGPWR" },
 608 #endif
 609   {  SIGQUIT,     "SIGQUIT" },
 610 #ifdef SIGRECONFIG
 611   {  SIGRECONFIG, "SIGRECONFIG" },
 612 #endif
 613 #ifdef SIGRECOVERY
 614   {  SIGRECOVERY, "SIGRECOVERY" },
 615 #endif
 616 #ifdef SIGRESERVE
 617   {  SIGRESERVE,  "SIGRESERVE" },
 618 #endif
 619 #ifdef SIGRETRACT
 620   {  SIGRETRACT,  "SIGRETRACT" },
 621 #endif
 622 #ifdef SIGSAK
 623   {  SIGSAK,      "SIGSAK" },
 624 #endif
 625   {  SIGSEGV,     "SIGSEGV" },
 626 #ifdef SIGSOUND
 627   {  SIGSOUND,    "SIGSOUND" },
 628 #endif
 629 #ifdef SIGSTKFLT
 630   {  SIGSTKFLT,    "SIGSTKFLT" },
 631 #endif
 632   {  SIGSTOP,     "SIGSTOP" },
 633   {  SIGSYS,      "SIGSYS" },
 634 #ifdef SIGSYSERROR
 635   {  SIGSYSERROR, "SIGSYSERROR" },
 636 #endif
 637 #ifdef SIGTALRM
 638   {  SIGTALRM,    "SIGTALRM" },
 639 #endif
 640   {  SIGTERM,     "SIGTERM" },
 641 #ifdef SIGTHAW
 642   {  SIGTHAW,     "SIGTHAW" },
 643 #endif
 644   {  SIGTRAP,     "SIGTRAP" },
 645 #ifdef SIGTSTP
 646   {  SIGTSTP,     "SIGTSTP" },
 647 #endif
 648   {  SIGTTIN,     "SIGTTIN" },
 649   {  SIGTTOU,     "SIGTTOU" },
 650 #ifdef SIGURG
 651   {  SIGURG,      "SIGURG" },
 652 #endif
 653   {  SIGUSR1,     "SIGUSR1" },
 654   {  SIGUSR2,     "SIGUSR2" },
 655 #ifdef SIGVIRT
 656   {  SIGVIRT,     "SIGVIRT" },
 657 #endif
 658   {  SIGVTALRM,   "SIGVTALRM" },
 659 #ifdef SIGWAITING
 660   {  SIGWAITING,  "SIGWAITING" },
 661 #endif
 662 #ifdef SIGWINCH
 663   {  SIGWINCH,    "SIGWINCH" },
 664 #endif
 665 #ifdef SIGWINDOW
 666   {  SIGWINDOW,   "SIGWINDOW" },
 667 #endif
 668   {  SIGXCPU,     "SIGXCPU" },
 669   {  SIGXFSZ,     "SIGXFSZ" },
 670 #ifdef SIGXRES
 671   {  SIGXRES,     "SIGXRES" },
 672 #endif
 673   { -1, NULL }
 674 };
 675 
 676 // Returned string is a constant. For unknown signals "UNKNOWN" is returned.
 677 const char* os::Posix::get_signal_name(int sig, char* out, size_t outlen) {
 678 
 679   const char* ret = NULL;
 680 
 681 #ifdef SIGRTMIN
 682   if (sig >= SIGRTMIN && sig <= SIGRTMAX) {
 683     if (sig == SIGRTMIN) {
 684       ret = "SIGRTMIN";
 685     } else if (sig == SIGRTMAX) {
 686       ret = "SIGRTMAX";
 687     } else {
 688       jio_snprintf(out, outlen, "SIGRTMIN+%d", sig - SIGRTMIN);
 689       return out;
 690     }
 691   }
 692 #endif
 693 
 694   if (sig > 0) {
 695     for (int idx = 0; g_signal_info[idx].sig != -1; idx ++) {
 696       if (g_signal_info[idx].sig == sig) {
 697         ret = g_signal_info[idx].name;
 698         break;
 699       }
 700     }
 701   }
 702 
 703   if (!ret) {
 704     if (!is_valid_signal(sig)) {
 705       ret = "INVALID";
 706     } else {
 707       ret = "UNKNOWN";
 708     }
 709   }
 710 
 711   if (out && outlen > 0) {
 712     strncpy(out, ret, outlen);
 713     out[outlen - 1] = '\0';
 714   }
 715   return out;
 716 }
 717 
 718 int os::Posix::get_signal_number(const char* signal_name) {
 719   char tmp[30];
 720   const char* s = signal_name;
 721   if (s[0] != 'S' || s[1] != 'I' || s[2] != 'G') {
 722     jio_snprintf(tmp, sizeof(tmp), "SIG%s", signal_name);
 723     s = tmp;
 724   }
 725   for (int idx = 0; g_signal_info[idx].sig != -1; idx ++) {
 726     if (strcmp(g_signal_info[idx].name, s) == 0) {
 727       return g_signal_info[idx].sig;
 728     }
 729   }
 730   return -1;
 731 }
 732 
 733 int os::get_signal_number(const char* signal_name) {
 734   return os::Posix::get_signal_number(signal_name);
 735 }
 736 
 737 // Returns true if signal number is valid.
 738 bool os::Posix::is_valid_signal(int sig) {
 739   // MacOS not really POSIX compliant: sigaddset does not return
 740   // an error for invalid signal numbers. However, MacOS does not
 741   // support real time signals and simply seems to have just 33
 742   // signals with no holes in the signal range.
 743 #ifdef __APPLE__
 744   return sig >= 1 && sig < NSIG;
 745 #else
 746   // Use sigaddset to check for signal validity.
 747   sigset_t set;
 748   if (sigaddset(&set, sig) == -1 && errno == EINVAL) {
 749     return false;
 750   }
 751   return true;
 752 #endif
 753 }
 754 
 755 // Returns:
 756 // NULL for an invalid signal number
 757 // "SIG<num>" for a valid but unknown signal number
 758 // signal name otherwise.
 759 const char* os::exception_name(int sig, char* buf, size_t size) {
 760   if (!os::Posix::is_valid_signal(sig)) {
 761     return NULL;
 762   }
 763   const char* const name = os::Posix::get_signal_name(sig, buf, size);
 764   if (strcmp(name, "UNKNOWN") == 0) {
 765     jio_snprintf(buf, size, "SIG%d", sig);
 766   }
 767   return buf;
 768 }
 769 
 770 #define NUM_IMPORTANT_SIGS 32
 771 // Returns one-line short description of a signal set in a user provided buffer.
 772 const char* os::Posix::describe_signal_set_short(const sigset_t* set, char* buffer, size_t buf_size) {
 773   assert(buf_size == (NUM_IMPORTANT_SIGS + 1), "wrong buffer size");
 774   // Note: for shortness, just print out the first 32. That should
 775   // cover most of the useful ones, apart from realtime signals.
 776   for (int sig = 1; sig <= NUM_IMPORTANT_SIGS; sig++) {
 777     const int rc = sigismember(set, sig);
 778     if (rc == -1 && errno == EINVAL) {
 779       buffer[sig-1] = '?';
 780     } else {
 781       buffer[sig-1] = rc == 0 ? '0' : '1';
 782     }
 783   }
 784   buffer[NUM_IMPORTANT_SIGS] = 0;
 785   return buffer;
 786 }
 787 
 788 // Prints one-line description of a signal set.
 789 void os::Posix::print_signal_set_short(outputStream* st, const sigset_t* set) {
 790   char buf[NUM_IMPORTANT_SIGS + 1];
 791   os::Posix::describe_signal_set_short(set, buf, sizeof(buf));
 792   st->print("%s", buf);
 793 }
 794 
 795 // Writes one-line description of a combination of sigaction.sa_flags into a user
 796 // provided buffer. Returns that buffer.
 797 const char* os::Posix::describe_sa_flags(int flags, char* buffer, size_t size) {
 798   char* p = buffer;
 799   size_t remaining = size;
 800   bool first = true;
 801   int idx = 0;
 802 
 803   assert(buffer, "invalid argument");
 804 
 805   if (size == 0) {
 806     return buffer;
 807   }
 808 
 809   strncpy(buffer, "none", size);
 810 
 811   const struct {
 812     // NB: i is an unsigned int here because SA_RESETHAND is on some
 813     // systems 0x80000000, which is implicitly unsigned.  Assignining
 814     // it to an int field would be an overflow in unsigned-to-signed
 815     // conversion.
 816     unsigned int i;
 817     const char* s;
 818   } flaginfo [] = {
 819     { SA_NOCLDSTOP, "SA_NOCLDSTOP" },
 820     { SA_ONSTACK,   "SA_ONSTACK"   },
 821     { SA_RESETHAND, "SA_RESETHAND" },
 822     { SA_RESTART,   "SA_RESTART"   },
 823     { SA_SIGINFO,   "SA_SIGINFO"   },
 824     { SA_NOCLDWAIT, "SA_NOCLDWAIT" },
 825     { SA_NODEFER,   "SA_NODEFER"   },
 826 #ifdef AIX
 827     { SA_ONSTACK,   "SA_ONSTACK"   },
 828     { SA_OLDSTYLE,  "SA_OLDSTYLE"  },
 829 #endif
 830     { 0, NULL }
 831   };
 832 
 833   for (idx = 0; flaginfo[idx].s && remaining > 1; idx++) {
 834     if (flags & flaginfo[idx].i) {
 835       if (first) {
 836         jio_snprintf(p, remaining, "%s", flaginfo[idx].s);
 837         first = false;
 838       } else {
 839         jio_snprintf(p, remaining, "|%s", flaginfo[idx].s);
 840       }
 841       const size_t len = strlen(p);
 842       p += len;
 843       remaining -= len;
 844     }
 845   }
 846 
 847   buffer[size - 1] = '\0';
 848 
 849   return buffer;
 850 }
 851 
 852 // Prints one-line description of a combination of sigaction.sa_flags.
 853 void os::Posix::print_sa_flags(outputStream* st, int flags) {
 854   char buffer[0x100];
 855   os::Posix::describe_sa_flags(flags, buffer, sizeof(buffer));
 856   st->print("%s", buffer);
 857 }
 858 
 859 // Helper function for os::Posix::print_siginfo_...():
 860 // return a textual description for signal code.
 861 struct enum_sigcode_desc_t {
 862   const char* s_name;
 863   const char* s_desc;
 864 };
 865 
 866 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) {
 867 
 868   const struct {
 869     int sig; int code; const char* s_code; const char* s_desc;
 870   } t1 [] = {
 871     { SIGILL,  ILL_ILLOPC,   "ILL_ILLOPC",   "Illegal opcode." },
 872     { SIGILL,  ILL_ILLOPN,   "ILL_ILLOPN",   "Illegal operand." },
 873     { SIGILL,  ILL_ILLADR,   "ILL_ILLADR",   "Illegal addressing mode." },
 874     { SIGILL,  ILL_ILLTRP,   "ILL_ILLTRP",   "Illegal trap." },
 875     { SIGILL,  ILL_PRVOPC,   "ILL_PRVOPC",   "Privileged opcode." },
 876     { SIGILL,  ILL_PRVREG,   "ILL_PRVREG",   "Privileged register." },
 877     { SIGILL,  ILL_COPROC,   "ILL_COPROC",   "Coprocessor error." },
 878     { SIGILL,  ILL_BADSTK,   "ILL_BADSTK",   "Internal stack error." },
 879 #if defined(IA64) && defined(LINUX)
 880     { SIGILL,  ILL_BADIADDR, "ILL_BADIADDR", "Unimplemented instruction address" },
 881     { SIGILL,  ILL_BREAK,    "ILL_BREAK",    "Application Break instruction" },
 882 #endif
 883     { SIGFPE,  FPE_INTDIV,   "FPE_INTDIV",   "Integer divide by zero." },
 884     { SIGFPE,  FPE_INTOVF,   "FPE_INTOVF",   "Integer overflow." },
 885     { SIGFPE,  FPE_FLTDIV,   "FPE_FLTDIV",   "Floating-point divide by zero." },
 886     { SIGFPE,  FPE_FLTOVF,   "FPE_FLTOVF",   "Floating-point overflow." },
 887     { SIGFPE,  FPE_FLTUND,   "FPE_FLTUND",   "Floating-point underflow." },
 888     { SIGFPE,  FPE_FLTRES,   "FPE_FLTRES",   "Floating-point inexact result." },
 889     { SIGFPE,  FPE_FLTINV,   "FPE_FLTINV",   "Invalid floating-point operation." },
 890     { SIGFPE,  FPE_FLTSUB,   "FPE_FLTSUB",   "Subscript out of range." },
 891     { SIGSEGV, SEGV_MAPERR,  "SEGV_MAPERR",  "Address not mapped to object." },
 892     { SIGSEGV, SEGV_ACCERR,  "SEGV_ACCERR",  "Invalid permissions for mapped object." },
 893 #ifdef AIX
 894     // no explanation found what keyerr would be
 895     { SIGSEGV, SEGV_KEYERR,  "SEGV_KEYERR",  "key error" },
 896 #endif
 897 #if defined(IA64) && !defined(AIX)
 898     { SIGSEGV, SEGV_PSTKOVF, "SEGV_PSTKOVF", "Paragraph stack overflow" },
 899 #endif
 900 #if defined(__sparc) && defined(SOLARIS)
 901 // define Solaris Sparc M7 ADI SEGV signals
 902 #if !defined(SEGV_ACCADI)
 903 #define SEGV_ACCADI 3
 904 #endif
 905     { SIGSEGV, SEGV_ACCADI,  "SEGV_ACCADI",  "ADI not enabled for mapped object." },
 906 #if !defined(SEGV_ACCDERR)
 907 #define SEGV_ACCDERR 4
 908 #endif
 909     { SIGSEGV, SEGV_ACCDERR, "SEGV_ACCDERR", "ADI disrupting exception." },
 910 #if !defined(SEGV_ACCPERR)
 911 #define SEGV_ACCPERR 5
 912 #endif
 913     { SIGSEGV, SEGV_ACCPERR, "SEGV_ACCPERR", "ADI precise exception." },
 914 #endif // defined(__sparc) && defined(SOLARIS)
 915     { SIGBUS,  BUS_ADRALN,   "BUS_ADRALN",   "Invalid address alignment." },
 916     { SIGBUS,  BUS_ADRERR,   "BUS_ADRERR",   "Nonexistent physical address." },
 917     { SIGBUS,  BUS_OBJERR,   "BUS_OBJERR",   "Object-specific hardware error." },
 918     { SIGTRAP, TRAP_BRKPT,   "TRAP_BRKPT",   "Process breakpoint." },
 919     { SIGTRAP, TRAP_TRACE,   "TRAP_TRACE",   "Process trace trap." },
 920     { SIGCHLD, CLD_EXITED,   "CLD_EXITED",   "Child has exited." },
 921     { SIGCHLD, CLD_KILLED,   "CLD_KILLED",   "Child has terminated abnormally and did not create a core file." },
 922     { SIGCHLD, CLD_DUMPED,   "CLD_DUMPED",   "Child has terminated abnormally and created a core file." },
 923     { SIGCHLD, CLD_TRAPPED,  "CLD_TRAPPED",  "Traced child has trapped." },
 924     { SIGCHLD, CLD_STOPPED,  "CLD_STOPPED",  "Child has stopped." },
 925     { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." },
 926 #ifdef SIGPOLL
 927     { SIGPOLL, POLL_OUT,     "POLL_OUT",     "Output buffers available." },
 928     { SIGPOLL, POLL_MSG,     "POLL_MSG",     "Input message available." },
 929     { SIGPOLL, POLL_ERR,     "POLL_ERR",     "I/O error." },
 930     { SIGPOLL, POLL_PRI,     "POLL_PRI",     "High priority input available." },
 931     { SIGPOLL, POLL_HUP,     "POLL_HUP",     "Device disconnected. [Option End]" },
 932 #endif
 933     { -1, -1, NULL, NULL }
 934   };
 935 
 936   // Codes valid in any signal context.
 937   const struct {
 938     int code; const char* s_code; const char* s_desc;
 939   } t2 [] = {
 940     { SI_USER,      "SI_USER",     "Signal sent by kill()." },
 941     { SI_QUEUE,     "SI_QUEUE",    "Signal sent by the sigqueue()." },
 942     { SI_TIMER,     "SI_TIMER",    "Signal generated by expiration of a timer set by timer_settime()." },
 943     { SI_ASYNCIO,   "SI_ASYNCIO",  "Signal generated by completion of an asynchronous I/O request." },
 944     { SI_MESGQ,     "SI_MESGQ",    "Signal generated by arrival of a message on an empty message queue." },
 945     // Linux specific
 946 #ifdef SI_TKILL
 947     { SI_TKILL,     "SI_TKILL",    "Signal sent by tkill (pthread_kill)" },
 948 #endif
 949 #ifdef SI_DETHREAD
 950     { SI_DETHREAD,  "SI_DETHREAD", "Signal sent by execve() killing subsidiary threads" },
 951 #endif
 952 #ifdef SI_KERNEL
 953     { SI_KERNEL,    "SI_KERNEL",   "Signal sent by kernel." },
 954 #endif
 955 #ifdef SI_SIGIO
 956     { SI_SIGIO,     "SI_SIGIO",    "Signal sent by queued SIGIO" },
 957 #endif
 958 
 959 #ifdef AIX
 960     { SI_UNDEFINED, "SI_UNDEFINED","siginfo contains partial information" },
 961     { SI_EMPTY,     "SI_EMPTY",    "siginfo contains no useful information" },
 962 #endif
 963 
 964 #ifdef __sun
 965     { SI_NOINFO,    "SI_NOINFO",   "No signal information" },
 966     { SI_RCTL,      "SI_RCTL",     "kernel generated signal via rctl action" },
 967     { SI_LWP,       "SI_LWP",      "Signal sent via lwp_kill" },
 968 #endif
 969 
 970     { -1, NULL, NULL }
 971   };
 972 
 973   const char* s_code = NULL;
 974   const char* s_desc = NULL;
 975 
 976   for (int i = 0; t1[i].sig != -1; i ++) {
 977     if (t1[i].sig == si->si_signo && t1[i].code == si->si_code) {
 978       s_code = t1[i].s_code;
 979       s_desc = t1[i].s_desc;
 980       break;
 981     }
 982   }
 983 
 984   if (s_code == NULL) {
 985     for (int i = 0; t2[i].s_code != NULL; i ++) {
 986       if (t2[i].code == si->si_code) {
 987         s_code = t2[i].s_code;
 988         s_desc = t2[i].s_desc;
 989       }
 990     }
 991   }
 992 
 993   if (s_code == NULL) {
 994     out->s_name = "unknown";
 995     out->s_desc = "unknown";
 996     return false;
 997   }
 998 
 999   out->s_name = s_code;
1000   out->s_desc = s_desc;
1001 
1002   return true;
1003 }
1004 
1005 void os::print_siginfo(outputStream* os, const void* si0) {
1006 
1007   const siginfo_t* const si = (const siginfo_t*) si0;
1008 
1009   char buf[20];
1010   os->print("siginfo:");
1011 
1012   if (!si) {
1013     os->print(" <null>");
1014     return;
1015   }
1016 
1017   const int sig = si->si_signo;
1018 
1019   os->print(" si_signo: %d (%s)", sig, os::Posix::get_signal_name(sig, buf, sizeof(buf)));
1020 
1021   enum_sigcode_desc_t ed;
1022   get_signal_code_description(si, &ed);
1023   os->print(", si_code: %d (%s)", si->si_code, ed.s_name);
1024 
1025   if (si->si_errno) {
1026     os->print(", si_errno: %d", si->si_errno);
1027   }
1028 
1029   // Output additional information depending on the signal code.
1030 
1031   // Note: Many implementations lump si_addr, si_pid, si_uid etc. together as unions,
1032   // so it depends on the context which member to use. For synchronous error signals,
1033   // we print si_addr, unless the signal was sent by another process or thread, in
1034   // which case we print out pid or tid of the sender.
1035   if (si->si_code == SI_USER || si->si_code == SI_QUEUE) {
1036     const pid_t pid = si->si_pid;
1037     os->print(", si_pid: %ld", (long) pid);
1038     if (IS_VALID_PID(pid)) {
1039       const pid_t me = getpid();
1040       if (me == pid) {
1041         os->print(" (current process)");
1042       }
1043     } else {
1044       os->print(" (invalid)");
1045     }
1046     os->print(", si_uid: %ld", (long) si->si_uid);
1047     if (sig == SIGCHLD) {
1048       os->print(", si_status: %d", si->si_status);
1049     }
1050   } else if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL ||
1051              sig == SIGTRAP || sig == SIGFPE) {
1052     os->print(", si_addr: " PTR_FORMAT, p2i(si->si_addr));
1053 #ifdef SIGPOLL
1054   } else if (sig == SIGPOLL) {
1055     os->print(", si_band: %ld", si->si_band);
1056 #endif
1057   }
1058 
1059 }
1060 
1061 int os::Posix::unblock_thread_signal_mask(const sigset_t *set) {
1062   return pthread_sigmask(SIG_UNBLOCK, set, NULL);
1063 }
1064 
1065 address os::Posix::ucontext_get_pc(const ucontext_t* ctx) {
1066 #if defined(AIX)
1067    return Aix::ucontext_get_pc(ctx);
1068 #elif defined(BSD)
1069    return Bsd::ucontext_get_pc(ctx);
1070 #elif defined(LINUX)
1071    return Linux::ucontext_get_pc(ctx);
1072 #elif defined(SOLARIS)
1073    return Solaris::ucontext_get_pc(ctx);
1074 #else
1075    VMError::report_and_die("unimplemented ucontext_get_pc");
1076 #endif
1077 }
1078 
1079 void os::Posix::ucontext_set_pc(ucontext_t* ctx, address pc) {
1080 #if defined(AIX)
1081    Aix::ucontext_set_pc(ctx, pc);
1082 #elif defined(BSD)
1083    Bsd::ucontext_set_pc(ctx, pc);
1084 #elif defined(LINUX)
1085    Linux::ucontext_set_pc(ctx, pc);
1086 #elif defined(SOLARIS)
1087    Solaris::ucontext_set_pc(ctx, pc);
1088 #else
1089    VMError::report_and_die("unimplemented ucontext_get_pc");
1090 #endif
1091 }
1092 
1093 char* os::Posix::describe_pthread_attr(char* buf, size_t buflen, const pthread_attr_t* attr) {
1094   size_t stack_size = 0;
1095   size_t guard_size = 0;
1096   int detachstate = 0;
1097   pthread_attr_getstacksize(attr, &stack_size);
1098   pthread_attr_getguardsize(attr, &guard_size);


1099   pthread_attr_getdetachstate(attr, &detachstate);
1100   jio_snprintf(buf, buflen, "stacksize: " SIZE_FORMAT "k, guardsize: " SIZE_FORMAT "k, %s",
1101     stack_size / 1024, guard_size / 1024,
1102     (detachstate == PTHREAD_CREATE_DETACHED ? "detached" : "joinable"));
1103   return buf;
1104 }
1105 
1106 // Check minimum allowable stack sizes for thread creation and to initialize
1107 // the java system classes, including StackOverflowError - depends on page
1108 // size.  Add two 4K pages for compiler2 recursion in main thread.
1109 // Add in 4*BytesPerWord 4K pages to account for VM stack during
1110 // class initialization depending on 32 or 64 bit VM.
1111 jint os::Posix::set_minimum_stack_sizes() {
1112   _java_thread_min_stack_allowed = MAX2(_java_thread_min_stack_allowed,
1113                                         JavaThread::stack_guard_zone_size() +
1114                                         JavaThread::stack_shadow_zone_size() +
1115                                         (4 * BytesPerWord COMPILER2_PRESENT(+ 2)) * 4 * K);
1116 
1117   _java_thread_min_stack_allowed = align_size_up(_java_thread_min_stack_allowed, vm_page_size());
1118 
1119   size_t stack_size_in_bytes = ThreadStackSize * K;
1120   if (stack_size_in_bytes != 0 &&
1121       stack_size_in_bytes < _java_thread_min_stack_allowed) {
1122     // The '-Xss' and '-XX:ThreadStackSize=N' options both set
1123     // ThreadStackSize so we go with "Java thread stack size" instead
1124     // of "ThreadStackSize" to be more friendly.
1125     tty->print_cr("\nThe Java thread stack size specified is too small. "
1126                   "Specify at least " SIZE_FORMAT "k",
1127                   _java_thread_min_stack_allowed / K);
1128     return JNI_ERR;
1129   }
1130 
1131 #ifdef SOLARIS
1132   // For 64kbps there will be a 64kb page size, which makes
1133   // the usable default stack size quite a bit less.  Increase the
1134   // stack for 64kb (or any > than 8kb) pages, this increases
1135   // virtual memory fragmentation (since we're not creating the
1136   // stack on a power of 2 boundary.  The real fix for this
1137   // should be to fix the guard page mechanism.
1138 
1139   if (vm_page_size() > 8*K) {
1140     stack_size_in_bytes = (stack_size_in_bytes != 0)
1141        ? stack_size_in_bytes +
1142          JavaThread::stack_red_zone_size() +
1143          JavaThread::stack_yellow_zone_size()
1144        : 0;
1145     ThreadStackSize = stack_size_in_bytes/K;
1146   }
1147 #endif // SOLARIS
1148 
1149   // Make the stack size a multiple of the page size so that
1150   // the yellow/red zones can be guarded.
1151   JavaThread::set_stack_size_at_create(round_to(stack_size_in_bytes,
1152                                                 vm_page_size()));
1153 
1154   _compiler_thread_min_stack_allowed = align_size_up(_compiler_thread_min_stack_allowed, vm_page_size());
1155 
1156   stack_size_in_bytes = CompilerThreadStackSize * K;
1157   if (stack_size_in_bytes != 0 &&
1158       stack_size_in_bytes < _compiler_thread_min_stack_allowed) {
1159     tty->print_cr("\nThe CompilerThreadStackSize specified is too small. "
1160                   "Specify at least " SIZE_FORMAT "k",
1161                   _compiler_thread_min_stack_allowed / K);
1162     return JNI_ERR;
1163   }
1164 
1165   _vm_internal_thread_min_stack_allowed = align_size_up(_vm_internal_thread_min_stack_allowed, vm_page_size());
1166 
1167   stack_size_in_bytes = VMThreadStackSize * K;
1168   if (stack_size_in_bytes != 0 &&
1169       stack_size_in_bytes < _vm_internal_thread_min_stack_allowed) {
1170     tty->print_cr("\nThe VMThreadStackSize specified is too small. "
1171                   "Specify at least " SIZE_FORMAT "k",
1172                   _vm_internal_thread_min_stack_allowed / K);
1173     return JNI_ERR;
1174   }
1175   return JNI_OK;
1176 }
1177 
1178 // Called when creating the thread.  The minimum stack sizes have already been calculated
1179 size_t os::Posix::get_initial_stack_size(ThreadType thr_type, size_t req_stack_size) {
1180   size_t stack_size;
1181   if (req_stack_size == 0) {
1182     stack_size = default_stack_size(thr_type);
1183   } else {
1184     stack_size = req_stack_size;
1185   }
1186 
1187   switch (thr_type) {
1188   case os::java_thread:
1189     // Java threads use ThreadStackSize which default value can be
1190     // changed with the flag -Xss
1191     if (req_stack_size == 0 && JavaThread::stack_size_at_create() > 0) {
1192       // no requested size and we have a more specific default value
1193       stack_size = JavaThread::stack_size_at_create();
1194     }
1195     stack_size = MAX2(stack_size,
1196                       _java_thread_min_stack_allowed);
1197     break;
1198   case os::compiler_thread:
1199     if (req_stack_size == 0 && CompilerThreadStackSize > 0) {
1200       // no requested size and we have a more specific default value
1201       stack_size = (size_t)(CompilerThreadStackSize * K);
1202     }
1203     stack_size = MAX2(stack_size,
1204                       _compiler_thread_min_stack_allowed);
1205     break;
1206   case os::vm_thread:
1207   case os::pgc_thread:
1208   case os::cgc_thread:
1209   case os::watcher_thread:
1210   default:  // presume the unknown thr_type is a VM internal
1211     if (req_stack_size == 0 && VMThreadStackSize > 0) {
1212       // no requested size and we have a more specific default value
1213       stack_size = (size_t)(VMThreadStackSize * K);
1214     }
1215 
1216     stack_size = MAX2(stack_size,
1217                       _vm_internal_thread_min_stack_allowed);
1218     break;
1219   }
1220 
1221   return stack_size;
1222 }
1223 
1224 os::WatcherThreadCrashProtection::WatcherThreadCrashProtection() {
1225   assert(Thread::current()->is_Watcher_thread(), "Must be WatcherThread");
1226 }
1227 
1228 /*
1229  * See the caveats for this class in os_posix.hpp
1230  * Protects the callback call so that SIGSEGV / SIGBUS jumps back into this
1231  * method and returns false. If none of the signals are raised, returns true.
1232  * The callback is supposed to provide the method that should be protected.
1233  */
1234 bool os::WatcherThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
1235   sigset_t saved_sig_mask;
1236 
1237   assert(Thread::current()->is_Watcher_thread(), "Only for WatcherThread");
1238   assert(!WatcherThread::watcher_thread()->has_crash_protection(),
1239       "crash_protection already set?");
1240 
1241   // we cannot rely on sigsetjmp/siglongjmp to save/restore the signal mask
1242   // since on at least some systems (OS X) siglongjmp will restore the mask
1243   // for the process, not the thread
1244   pthread_sigmask(0, NULL, &saved_sig_mask);
1245   if (sigsetjmp(_jmpbuf, 0) == 0) {
1246     // make sure we can see in the signal handler that we have crash protection
1247     // installed
1248     WatcherThread::watcher_thread()->set_crash_protection(this);
1249     cb.call();
1250     // and clear the crash protection
1251     WatcherThread::watcher_thread()->set_crash_protection(NULL);
1252     return true;
1253   }
1254   // this happens when we siglongjmp() back
1255   pthread_sigmask(SIG_SETMASK, &saved_sig_mask, NULL);
1256   WatcherThread::watcher_thread()->set_crash_protection(NULL);
1257   return false;
1258 }
1259 
1260 void os::WatcherThreadCrashProtection::restore() {
1261   assert(WatcherThread::watcher_thread()->has_crash_protection(),
1262       "must have crash protection");
1263 
1264   siglongjmp(_jmpbuf, 1);
1265 }
1266 
1267 void os::WatcherThreadCrashProtection::check_crash_protection(int sig,
1268     Thread* thread) {
1269 
1270   if (thread != NULL &&
1271       thread->is_Watcher_thread() &&
1272       WatcherThread::watcher_thread()->has_crash_protection()) {
1273 
1274     if (sig == SIGSEGV || sig == SIGBUS) {
1275       WatcherThread::watcher_thread()->crash_protection()->restore();
1276     }
1277   }
1278 }
1279 
1280 #define check_with_errno(check_type, cond, msg)                             \
1281   do {                                                                      \
1282     int err = errno;                                                        \
1283     check_type(cond, "%s; error='%s' (errno=%s)", msg, os::strerror(err),   \
1284                os::errno_name(err));                                        \
1285 } while (false)
1286 
1287 #define assert_with_errno(cond, msg)    check_with_errno(assert, cond, msg)
1288 #define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg)
1289 
1290 // POSIX unamed semaphores are not supported on OS X.
1291 #ifndef __APPLE__
1292 
1293 PosixSemaphore::PosixSemaphore(uint value) {
1294   int ret = sem_init(&_semaphore, 0, value);
1295 
1296   guarantee_with_errno(ret == 0, "Failed to initialize semaphore");
1297 }
1298 
1299 PosixSemaphore::~PosixSemaphore() {
1300   sem_destroy(&_semaphore);
1301 }
1302 
1303 void PosixSemaphore::signal(uint count) {
1304   for (uint i = 0; i < count; i++) {
1305     int ret = sem_post(&_semaphore);
1306 
1307     assert_with_errno(ret == 0, "sem_post failed");
1308   }
1309 }
1310 
1311 void PosixSemaphore::wait() {
1312   int ret;
1313 
1314   do {
1315     ret = sem_wait(&_semaphore);
1316   } while (ret != 0 && errno == EINTR);
1317 
1318   assert_with_errno(ret == 0, "sem_wait failed");
1319 }
1320 
1321 bool PosixSemaphore::trywait() {
1322   int ret;
1323 
1324   do {
1325     ret = sem_trywait(&_semaphore);
1326   } while (ret != 0 && errno == EINTR);
1327 
1328   assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed");
1329 
1330   return ret == 0;
1331 }
1332 
1333 bool PosixSemaphore::timedwait(struct timespec ts) {
1334   while (true) {
1335     int result = sem_timedwait(&_semaphore, &ts);
1336     if (result == 0) {
1337       return true;
1338     } else if (errno == EINTR) {
1339       continue;
1340     } else if (errno == ETIMEDOUT) {
1341       return false;
1342     } else {
1343       assert_with_errno(false, "timedwait failed");
1344       return false;
1345     }
1346   }
1347 }
1348 
1349 #endif // __APPLE__
--- EOF ---