src/os/bsd/vm/os_bsd.cpp

Fri, 05 Apr 2013 10:38:08 -0700

author
dcubed
date
Fri, 05 Apr 2013 10:38:08 -0700
changeset 4891
8be1318fbe77
parent 4854
754c24457b20
parent 4889
cc32ccaaf47f
child 4989
f32b6c267d2e
child 5027
e12c9b3740db
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1999, 2013, 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  */
    25 // no precompiled headers
    26 #include "classfile/classLoader.hpp"
    27 #include "classfile/systemDictionary.hpp"
    28 #include "classfile/vmSymbols.hpp"
    29 #include "code/icBuffer.hpp"
    30 #include "code/vtableStubs.hpp"
    31 #include "compiler/compileBroker.hpp"
    32 #include "compiler/disassembler.hpp"
    33 #include "interpreter/interpreter.hpp"
    34 #include "jvm_bsd.h"
    35 #include "memory/allocation.inline.hpp"
    36 #include "memory/filemap.hpp"
    37 #include "mutex_bsd.inline.hpp"
    38 #include "oops/oop.inline.hpp"
    39 #include "os_share_bsd.hpp"
    40 #include "prims/jniFastGetField.hpp"
    41 #include "prims/jvm.h"
    42 #include "prims/jvm_misc.hpp"
    43 #include "runtime/arguments.hpp"
    44 #include "runtime/extendedPC.hpp"
    45 #include "runtime/globals.hpp"
    46 #include "runtime/interfaceSupport.hpp"
    47 #include "runtime/java.hpp"
    48 #include "runtime/javaCalls.hpp"
    49 #include "runtime/mutexLocker.hpp"
    50 #include "runtime/objectMonitor.hpp"
    51 #include "runtime/osThread.hpp"
    52 #include "runtime/perfMemory.hpp"
    53 #include "runtime/sharedRuntime.hpp"
    54 #include "runtime/statSampler.hpp"
    55 #include "runtime/stubRoutines.hpp"
    56 #include "runtime/thread.inline.hpp"
    57 #include "runtime/threadCritical.hpp"
    58 #include "runtime/timer.hpp"
    59 #include "services/attachListener.hpp"
    60 #include "services/memTracker.hpp"
    61 #include "services/runtimeService.hpp"
    62 #include "utilities/decoder.hpp"
    63 #include "utilities/defaultStream.hpp"
    64 #include "utilities/events.hpp"
    65 #include "utilities/growableArray.hpp"
    66 #include "utilities/vmError.hpp"
    68 // put OS-includes here
    69 # include <sys/types.h>
    70 # include <sys/mman.h>
    71 # include <sys/stat.h>
    72 # include <sys/select.h>
    73 # include <pthread.h>
    74 # include <signal.h>
    75 # include <errno.h>
    76 # include <dlfcn.h>
    77 # include <stdio.h>
    78 # include <unistd.h>
    79 # include <sys/resource.h>
    80 # include <pthread.h>
    81 # include <sys/stat.h>
    82 # include <sys/time.h>
    83 # include <sys/times.h>
    84 # include <sys/utsname.h>
    85 # include <sys/socket.h>
    86 # include <sys/wait.h>
    87 # include <time.h>
    88 # include <pwd.h>
    89 # include <poll.h>
    90 # include <semaphore.h>
    91 # include <fcntl.h>
    92 # include <string.h>
    93 # include <sys/param.h>
    94 # include <sys/sysctl.h>
    95 # include <sys/ipc.h>
    96 # include <sys/shm.h>
    97 #ifndef __APPLE__
    98 # include <link.h>
    99 #endif
   100 # include <stdint.h>
   101 # include <inttypes.h>
   102 # include <sys/ioctl.h>
   104 #if defined(__FreeBSD__) || defined(__NetBSD__)
   105 # include <elf.h>
   106 #endif
   108 #ifdef __APPLE__
   109 # include <mach/mach.h> // semaphore_* API
   110 # include <mach-o/dyld.h>
   111 # include <sys/proc_info.h>
   112 # include <objc/objc-auto.h>
   113 #endif
   115 #ifndef MAP_ANONYMOUS
   116 #define MAP_ANONYMOUS MAP_ANON
   117 #endif
   119 #define MAX_PATH    (2 * K)
   121 // for timer info max values which include all bits
   122 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
   124 #define LARGEPAGES_BIT (1 << 6)
   125 ////////////////////////////////////////////////////////////////////////////////
   126 // global variables
   127 julong os::Bsd::_physical_memory = 0;
   130 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
   131 pthread_t os::Bsd::_main_thread;
   132 int os::Bsd::_page_size = -1;
   134 static jlong initial_time_count=0;
   136 static int clock_tics_per_sec = 100;
   138 // For diagnostics to print a message once. see run_periodic_checks
   139 static sigset_t check_signal_done;
   140 static bool check_signals = true;
   142 static pid_t _initial_pid = 0;
   144 /* Signal number used to suspend/resume a thread */
   146 /* do not use any signal number less than SIGSEGV, see 4355769 */
   147 static int SR_signum = SIGUSR2;
   148 sigset_t SR_sigset;
   151 ////////////////////////////////////////////////////////////////////////////////
   152 // utility functions
   154 static int SR_initialize();
   156 julong os::available_memory() {
   157   return Bsd::available_memory();
   158 }
   160 julong os::Bsd::available_memory() {
   161   // XXXBSD: this is just a stopgap implementation
   162   return physical_memory() >> 2;
   163 }
   165 julong os::physical_memory() {
   166   return Bsd::physical_memory();
   167 }
   169 ////////////////////////////////////////////////////////////////////////////////
   170 // environment support
   172 bool os::getenv(const char* name, char* buf, int len) {
   173   const char* val = ::getenv(name);
   174   if (val != NULL && strlen(val) < (size_t)len) {
   175     strcpy(buf, val);
   176     return true;
   177   }
   178   if (len > 0) buf[0] = 0;  // return a null string
   179   return false;
   180 }
   183 // Return true if user is running as root.
   185 bool os::have_special_privileges() {
   186   static bool init = false;
   187   static bool privileges = false;
   188   if (!init) {
   189     privileges = (getuid() != geteuid()) || (getgid() != getegid());
   190     init = true;
   191   }
   192   return privileges;
   193 }
   197 // Cpu architecture string
   198 #if   defined(ZERO)
   199 static char cpu_arch[] = ZERO_LIBARCH;
   200 #elif defined(IA64)
   201 static char cpu_arch[] = "ia64";
   202 #elif defined(IA32)
   203 static char cpu_arch[] = "i386";
   204 #elif defined(AMD64)
   205 static char cpu_arch[] = "amd64";
   206 #elif defined(ARM)
   207 static char cpu_arch[] = "arm";
   208 #elif defined(PPC)
   209 static char cpu_arch[] = "ppc";
   210 #elif defined(SPARC)
   211 #  ifdef _LP64
   212 static char cpu_arch[] = "sparcv9";
   213 #  else
   214 static char cpu_arch[] = "sparc";
   215 #  endif
   216 #else
   217 #error Add appropriate cpu_arch setting
   218 #endif
   220 // Compiler variant
   221 #ifdef COMPILER2
   222 #define COMPILER_VARIANT "server"
   223 #else
   224 #define COMPILER_VARIANT "client"
   225 #endif
   228 void os::Bsd::initialize_system_info() {
   229   int mib[2];
   230   size_t len;
   231   int cpu_val;
   232   julong mem_val;
   234   /* get processors count via hw.ncpus sysctl */
   235   mib[0] = CTL_HW;
   236   mib[1] = HW_NCPU;
   237   len = sizeof(cpu_val);
   238   if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
   239        assert(len == sizeof(cpu_val), "unexpected data size");
   240        set_processor_count(cpu_val);
   241   }
   242   else {
   243        set_processor_count(1);   // fallback
   244   }
   246   /* get physical memory via hw.memsize sysctl (hw.memsize is used
   247    * since it returns a 64 bit value)
   248    */
   249   mib[0] = CTL_HW;
   250   mib[1] = HW_MEMSIZE;
   251   len = sizeof(mem_val);
   252   if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
   253        assert(len == sizeof(mem_val), "unexpected data size");
   254        _physical_memory = mem_val;
   255   } else {
   256        _physical_memory = 256*1024*1024;       // fallback (XXXBSD?)
   257   }
   259 #ifdef __OpenBSD__
   260   {
   261        // limit _physical_memory memory view on OpenBSD since
   262        // datasize rlimit restricts us anyway.
   263        struct rlimit limits;
   264        getrlimit(RLIMIT_DATA, &limits);
   265        _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
   266   }
   267 #endif
   268 }
   270 #ifdef __APPLE__
   271 static const char *get_home() {
   272   const char *home_dir = ::getenv("HOME");
   273   if ((home_dir == NULL) || (*home_dir == '\0')) {
   274     struct passwd *passwd_info = getpwuid(geteuid());
   275     if (passwd_info != NULL) {
   276       home_dir = passwd_info->pw_dir;
   277     }
   278   }
   280   return home_dir;
   281 }
   282 #endif
   284 void os::init_system_properties_values() {
   285 //  char arch[12];
   286 //  sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
   288   // The next steps are taken in the product version:
   289   //
   290   // Obtain the JAVA_HOME value from the location of libjvm.so.
   291   // This library should be located at:
   292   // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
   293   //
   294   // If "/jre/lib/" appears at the right place in the path, then we
   295   // assume libjvm.so is installed in a JDK and we use this path.
   296   //
   297   // Otherwise exit with message: "Could not create the Java virtual machine."
   298   //
   299   // The following extra steps are taken in the debugging version:
   300   //
   301   // If "/jre/lib/" does NOT appear at the right place in the path
   302   // instead of exit check for $JAVA_HOME environment variable.
   303   //
   304   // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
   305   // then we append a fake suffix "hotspot/libjvm.so" to this path so
   306   // it looks like libjvm.so is installed there
   307   // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
   308   //
   309   // Otherwise exit.
   310   //
   311   // Important note: if the location of libjvm.so changes this
   312   // code needs to be changed accordingly.
   314   // The next few definitions allow the code to be verbatim:
   315 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
   316 #define getenv(n) ::getenv(n)
   318 /*
   319  * See ld(1):
   320  *      The linker uses the following search paths to locate required
   321  *      shared libraries:
   322  *        1: ...
   323  *        ...
   324  *        7: The default directories, normally /lib and /usr/lib.
   325  */
   326 #ifndef DEFAULT_LIBPATH
   327 #define DEFAULT_LIBPATH "/lib:/usr/lib"
   328 #endif
   330 #define EXTENSIONS_DIR  "/lib/ext"
   331 #define ENDORSED_DIR    "/lib/endorsed"
   332 #define REG_DIR         "/usr/java/packages"
   334 #ifdef __APPLE__
   335 #define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
   336 #define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
   337         const char *user_home_dir = get_home();
   338         // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
   339         int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
   340             sizeof(SYS_EXTENSIONS_DIRS);
   341 #endif
   343   {
   344     /* sysclasspath, java_home, dll_dir */
   345     {
   346         char *home_path;
   347         char *dll_path;
   348         char *pslash;
   349         char buf[MAXPATHLEN];
   350         os::jvm_path(buf, sizeof(buf));
   352         // Found the full path to libjvm.so.
   353         // Now cut the path to <java_home>/jre if we can.
   354         *(strrchr(buf, '/')) = '\0';  /* get rid of /libjvm.so */
   355         pslash = strrchr(buf, '/');
   356         if (pslash != NULL)
   357             *pslash = '\0';           /* get rid of /{client|server|hotspot} */
   358         dll_path = malloc(strlen(buf) + 1);
   359         if (dll_path == NULL)
   360             return;
   361         strcpy(dll_path, buf);
   362         Arguments::set_dll_dir(dll_path);
   364         if (pslash != NULL) {
   365             pslash = strrchr(buf, '/');
   366             if (pslash != NULL) {
   367                 *pslash = '\0';       /* get rid of /<arch> (/lib on macosx) */
   368 #ifndef __APPLE__
   369                 pslash = strrchr(buf, '/');
   370                 if (pslash != NULL)
   371                     *pslash = '\0';   /* get rid of /lib */
   372 #endif
   373             }
   374         }
   376         home_path = malloc(strlen(buf) + 1);
   377         if (home_path == NULL)
   378             return;
   379         strcpy(home_path, buf);
   380         Arguments::set_java_home(home_path);
   382         if (!set_boot_path('/', ':'))
   383             return;
   384     }
   386     /*
   387      * Where to look for native libraries
   388      *
   389      * Note: Due to a legacy implementation, most of the library path
   390      * is set in the launcher.  This was to accomodate linking restrictions
   391      * on legacy Bsd implementations (which are no longer supported).
   392      * Eventually, all the library path setting will be done here.
   393      *
   394      * However, to prevent the proliferation of improperly built native
   395      * libraries, the new path component /usr/java/packages is added here.
   396      * Eventually, all the library path setting will be done here.
   397      */
   398     {
   399         char *ld_library_path;
   401         /*
   402          * Construct the invariant part of ld_library_path. Note that the
   403          * space for the colon and the trailing null are provided by the
   404          * nulls included by the sizeof operator (so actually we allocate
   405          * a byte more than necessary).
   406          */
   407 #ifdef __APPLE__
   408         ld_library_path = (char *) malloc(system_ext_size);
   409         sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
   410 #else
   411         ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
   412             strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
   413         sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
   414 #endif
   416         /*
   417          * Get the user setting of LD_LIBRARY_PATH, and prepended it.  It
   418          * should always exist (until the legacy problem cited above is
   419          * addressed).
   420          */
   421 #ifdef __APPLE__
   422         // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
   423         char *l = getenv("JAVA_LIBRARY_PATH");
   424         if (l != NULL) {
   425             char *t = ld_library_path;
   426             /* That's +1 for the colon and +1 for the trailing '\0' */
   427             ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
   428             sprintf(ld_library_path, "%s:%s", l, t);
   429             free(t);
   430         }
   432         char *v = getenv("DYLD_LIBRARY_PATH");
   433 #else
   434         char *v = getenv("LD_LIBRARY_PATH");
   435 #endif
   436         if (v != NULL) {
   437             char *t = ld_library_path;
   438             /* That's +1 for the colon and +1 for the trailing '\0' */
   439             ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
   440             sprintf(ld_library_path, "%s:%s", v, t);
   441             free(t);
   442         }
   444 #ifdef __APPLE__
   445         // Apple's Java6 has "." at the beginning of java.library.path.
   446         // OpenJDK on Windows has "." at the end of java.library.path.
   447         // OpenJDK on Linux and Solaris don't have "." in java.library.path
   448         // at all. To ease the transition from Apple's Java6 to OpenJDK7,
   449         // "." is appended to the end of java.library.path. Yes, this
   450         // could cause a change in behavior, but Apple's Java6 behavior
   451         // can be achieved by putting "." at the beginning of the
   452         // JAVA_LIBRARY_PATH environment variable.
   453         {
   454             char *t = ld_library_path;
   455             // that's +3 for appending ":." and the trailing '\0'
   456             ld_library_path = (char *) malloc(strlen(t) + 3);
   457             sprintf(ld_library_path, "%s:%s", t, ".");
   458             free(t);
   459         }
   460 #endif
   462         Arguments::set_library_path(ld_library_path);
   463     }
   465     /*
   466      * Extensions directories.
   467      *
   468      * Note that the space for the colon and the trailing null are provided
   469      * by the nulls included by the sizeof operator (so actually one byte more
   470      * than necessary is allocated).
   471      */
   472     {
   473 #ifdef __APPLE__
   474         char *buf = malloc(strlen(Arguments::get_java_home()) +
   475             sizeof(EXTENSIONS_DIR) + system_ext_size);
   476         sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
   477             SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
   478 #else
   479         char *buf = malloc(strlen(Arguments::get_java_home()) +
   480             sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
   481         sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
   482             Arguments::get_java_home());
   483 #endif
   485         Arguments::set_ext_dirs(buf);
   486     }
   488     /* Endorsed standards default directory. */
   489     {
   490         char * buf;
   491         buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
   492         sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
   493         Arguments::set_endorsed_dirs(buf);
   494     }
   495   }
   497 #ifdef __APPLE__
   498 #undef SYS_EXTENSIONS_DIR
   499 #endif
   500 #undef malloc
   501 #undef getenv
   502 #undef EXTENSIONS_DIR
   503 #undef ENDORSED_DIR
   505   // Done
   506   return;
   507 }
   509 ////////////////////////////////////////////////////////////////////////////////
   510 // breakpoint support
   512 void os::breakpoint() {
   513   BREAKPOINT;
   514 }
   516 extern "C" void breakpoint() {
   517   // use debugger to set breakpoint here
   518 }
   520 ////////////////////////////////////////////////////////////////////////////////
   521 // signal support
   523 debug_only(static bool signal_sets_initialized = false);
   524 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
   526 bool os::Bsd::is_sig_ignored(int sig) {
   527       struct sigaction oact;
   528       sigaction(sig, (struct sigaction*)NULL, &oact);
   529       void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
   530                                      : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
   531       if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
   532            return true;
   533       else
   534            return false;
   535 }
   537 void os::Bsd::signal_sets_init() {
   538   // Should also have an assertion stating we are still single-threaded.
   539   assert(!signal_sets_initialized, "Already initialized");
   540   // Fill in signals that are necessarily unblocked for all threads in
   541   // the VM. Currently, we unblock the following signals:
   542   // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
   543   //                         by -Xrs (=ReduceSignalUsage));
   544   // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
   545   // other threads. The "ReduceSignalUsage" boolean tells us not to alter
   546   // the dispositions or masks wrt these signals.
   547   // Programs embedding the VM that want to use the above signals for their
   548   // own purposes must, at this time, use the "-Xrs" option to prevent
   549   // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
   550   // (See bug 4345157, and other related bugs).
   551   // In reality, though, unblocking these signals is really a nop, since
   552   // these signals are not blocked by default.
   553   sigemptyset(&unblocked_sigs);
   554   sigemptyset(&allowdebug_blocked_sigs);
   555   sigaddset(&unblocked_sigs, SIGILL);
   556   sigaddset(&unblocked_sigs, SIGSEGV);
   557   sigaddset(&unblocked_sigs, SIGBUS);
   558   sigaddset(&unblocked_sigs, SIGFPE);
   559   sigaddset(&unblocked_sigs, SR_signum);
   561   if (!ReduceSignalUsage) {
   562    if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
   563       sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
   564       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
   565    }
   566    if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
   567       sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
   568       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
   569    }
   570    if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
   571       sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
   572       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
   573    }
   574   }
   575   // Fill in signals that are blocked by all but the VM thread.
   576   sigemptyset(&vm_sigs);
   577   if (!ReduceSignalUsage)
   578     sigaddset(&vm_sigs, BREAK_SIGNAL);
   579   debug_only(signal_sets_initialized = true);
   581 }
   583 // These are signals that are unblocked while a thread is running Java.
   584 // (For some reason, they get blocked by default.)
   585 sigset_t* os::Bsd::unblocked_signals() {
   586   assert(signal_sets_initialized, "Not initialized");
   587   return &unblocked_sigs;
   588 }
   590 // These are the signals that are blocked while a (non-VM) thread is
   591 // running Java. Only the VM thread handles these signals.
   592 sigset_t* os::Bsd::vm_signals() {
   593   assert(signal_sets_initialized, "Not initialized");
   594   return &vm_sigs;
   595 }
   597 // These are signals that are blocked during cond_wait to allow debugger in
   598 sigset_t* os::Bsd::allowdebug_blocked_signals() {
   599   assert(signal_sets_initialized, "Not initialized");
   600   return &allowdebug_blocked_sigs;
   601 }
   603 void os::Bsd::hotspot_sigmask(Thread* thread) {
   605   //Save caller's signal mask before setting VM signal mask
   606   sigset_t caller_sigmask;
   607   pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
   609   OSThread* osthread = thread->osthread();
   610   osthread->set_caller_sigmask(caller_sigmask);
   612   pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
   614   if (!ReduceSignalUsage) {
   615     if (thread->is_VM_thread()) {
   616       // Only the VM thread handles BREAK_SIGNAL ...
   617       pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
   618     } else {
   619       // ... all other threads block BREAK_SIGNAL
   620       pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
   621     }
   622   }
   623 }
   626 //////////////////////////////////////////////////////////////////////////////
   627 // create new thread
   629 static address highest_vm_reserved_address();
   631 // check if it's safe to start a new thread
   632 static bool _thread_safety_check(Thread* thread) {
   633   return true;
   634 }
   636 #ifdef __APPLE__
   637 // library handle for calling objc_registerThreadWithCollector()
   638 // without static linking to the libobjc library
   639 #define OBJC_LIB "/usr/lib/libobjc.dylib"
   640 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
   641 typedef void (*objc_registerThreadWithCollector_t)();
   642 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
   643 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
   644 #endif
   646 #ifdef __APPLE__
   647 static uint64_t locate_unique_thread_id() {
   648   // Additional thread_id used to correlate threads in SA
   649   thread_identifier_info_data_t     m_ident_info;
   650   mach_msg_type_number_t            count = THREAD_IDENTIFIER_INFO_COUNT;
   652   thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
   653               (thread_info_t) &m_ident_info, &count);
   654   return m_ident_info.thread_id;
   655 }
   656 #endif
   658 // Thread start routine for all newly created threads
   659 static void *java_start(Thread *thread) {
   660   // Try to randomize the cache line index of hot stack frames.
   661   // This helps when threads of the same stack traces evict each other's
   662   // cache lines. The threads can be either from the same JVM instance, or
   663   // from different JVM instances. The benefit is especially true for
   664   // processors with hyperthreading technology.
   665   static int counter = 0;
   666   int pid = os::current_process_id();
   667   alloca(((pid ^ counter++) & 7) * 128);
   669   ThreadLocalStorage::set_thread(thread);
   671   OSThread* osthread = thread->osthread();
   672   Monitor* sync = osthread->startThread_lock();
   674   // non floating stack BsdThreads needs extra check, see above
   675   if (!_thread_safety_check(thread)) {
   676     // notify parent thread
   677     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   678     osthread->set_state(ZOMBIE);
   679     sync->notify_all();
   680     return NULL;
   681   }
   683 #ifdef __APPLE__
   684   // thread_id is mach thread on macos
   685   osthread->set_thread_id(::mach_thread_self());
   686   osthread->set_unique_thread_id(locate_unique_thread_id());
   687 #else
   688   // thread_id is pthread_id on BSD
   689   osthread->set_thread_id(::pthread_self());
   690 #endif
   691   // initialize signal mask for this thread
   692   os::Bsd::hotspot_sigmask(thread);
   694   // initialize floating point control register
   695   os::Bsd::init_thread_fpu_state();
   697 #ifdef __APPLE__
   698   // register thread with objc gc
   699   if (objc_registerThreadWithCollectorFunction != NULL) {
   700     objc_registerThreadWithCollectorFunction();
   701   }
   702 #endif
   704   // handshaking with parent thread
   705   {
   706     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   708     // notify parent thread
   709     osthread->set_state(INITIALIZED);
   710     sync->notify_all();
   712     // wait until os::start_thread()
   713     while (osthread->get_state() == INITIALIZED) {
   714       sync->wait(Mutex::_no_safepoint_check_flag);
   715     }
   716   }
   718   // call one more level start routine
   719   thread->run();
   721   return 0;
   722 }
   724 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
   725   assert(thread->osthread() == NULL, "caller responsible");
   727   // Allocate the OSThread object
   728   OSThread* osthread = new OSThread(NULL, NULL);
   729   if (osthread == NULL) {
   730     return false;
   731   }
   733   // set the correct thread state
   734   osthread->set_thread_type(thr_type);
   736   // Initial state is ALLOCATED but not INITIALIZED
   737   osthread->set_state(ALLOCATED);
   739   thread->set_osthread(osthread);
   741   // init thread attributes
   742   pthread_attr_t attr;
   743   pthread_attr_init(&attr);
   744   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
   746   // stack size
   747   if (os::Bsd::supports_variable_stack_size()) {
   748     // calculate stack size if it's not specified by caller
   749     if (stack_size == 0) {
   750       stack_size = os::Bsd::default_stack_size(thr_type);
   752       switch (thr_type) {
   753       case os::java_thread:
   754         // Java threads use ThreadStackSize which default value can be
   755         // changed with the flag -Xss
   756         assert (JavaThread::stack_size_at_create() > 0, "this should be set");
   757         stack_size = JavaThread::stack_size_at_create();
   758         break;
   759       case os::compiler_thread:
   760         if (CompilerThreadStackSize > 0) {
   761           stack_size = (size_t)(CompilerThreadStackSize * K);
   762           break;
   763         } // else fall through:
   764           // use VMThreadStackSize if CompilerThreadStackSize is not defined
   765       case os::vm_thread:
   766       case os::pgc_thread:
   767       case os::cgc_thread:
   768       case os::watcher_thread:
   769         if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
   770         break;
   771       }
   772     }
   774     stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
   775     pthread_attr_setstacksize(&attr, stack_size);
   776   } else {
   777     // let pthread_create() pick the default value.
   778   }
   780   ThreadState state;
   782   {
   783     pthread_t tid;
   784     int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
   786     pthread_attr_destroy(&attr);
   788     if (ret != 0) {
   789       if (PrintMiscellaneous && (Verbose || WizardMode)) {
   790         perror("pthread_create()");
   791       }
   792       // Need to clean up stuff we've allocated so far
   793       thread->set_osthread(NULL);
   794       delete osthread;
   795       return false;
   796     }
   798     // Store pthread info into the OSThread
   799     osthread->set_pthread_id(tid);
   801     // Wait until child thread is either initialized or aborted
   802     {
   803       Monitor* sync_with_child = osthread->startThread_lock();
   804       MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   805       while ((state = osthread->get_state()) == ALLOCATED) {
   806         sync_with_child->wait(Mutex::_no_safepoint_check_flag);
   807       }
   808     }
   810   }
   812   // Aborted due to thread limit being reached
   813   if (state == ZOMBIE) {
   814       thread->set_osthread(NULL);
   815       delete osthread;
   816       return false;
   817   }
   819   // The thread is returned suspended (in state INITIALIZED),
   820   // and is started higher up in the call chain
   821   assert(state == INITIALIZED, "race condition");
   822   return true;
   823 }
   825 /////////////////////////////////////////////////////////////////////////////
   826 // attach existing thread
   828 // bootstrap the main thread
   829 bool os::create_main_thread(JavaThread* thread) {
   830   assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
   831   return create_attached_thread(thread);
   832 }
   834 bool os::create_attached_thread(JavaThread* thread) {
   835 #ifdef ASSERT
   836     thread->verify_not_published();
   837 #endif
   839   // Allocate the OSThread object
   840   OSThread* osthread = new OSThread(NULL, NULL);
   842   if (osthread == NULL) {
   843     return false;
   844   }
   846   // Store pthread info into the OSThread
   847 #ifdef __APPLE__
   848   osthread->set_thread_id(::mach_thread_self());
   849   osthread->set_unique_thread_id(locate_unique_thread_id());
   850 #else
   851   osthread->set_thread_id(::pthread_self());
   852 #endif
   853   osthread->set_pthread_id(::pthread_self());
   855   // initialize floating point control register
   856   os::Bsd::init_thread_fpu_state();
   858   // Initial thread state is RUNNABLE
   859   osthread->set_state(RUNNABLE);
   861   thread->set_osthread(osthread);
   863   // initialize signal mask for this thread
   864   // and save the caller's signal mask
   865   os::Bsd::hotspot_sigmask(thread);
   867   return true;
   868 }
   870 void os::pd_start_thread(Thread* thread) {
   871   OSThread * osthread = thread->osthread();
   872   assert(osthread->get_state() != INITIALIZED, "just checking");
   873   Monitor* sync_with_child = osthread->startThread_lock();
   874   MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   875   sync_with_child->notify();
   876 }
   878 // Free Bsd resources related to the OSThread
   879 void os::free_thread(OSThread* osthread) {
   880   assert(osthread != NULL, "osthread not set");
   882   if (Thread::current()->osthread() == osthread) {
   883     // Restore caller's signal mask
   884     sigset_t sigmask = osthread->caller_sigmask();
   885     pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
   886    }
   888   delete osthread;
   889 }
   891 //////////////////////////////////////////////////////////////////////////////
   892 // thread local storage
   894 int os::allocate_thread_local_storage() {
   895   pthread_key_t key;
   896   int rslt = pthread_key_create(&key, NULL);
   897   assert(rslt == 0, "cannot allocate thread local storage");
   898   return (int)key;
   899 }
   901 // Note: This is currently not used by VM, as we don't destroy TLS key
   902 // on VM exit.
   903 void os::free_thread_local_storage(int index) {
   904   int rslt = pthread_key_delete((pthread_key_t)index);
   905   assert(rslt == 0, "invalid index");
   906 }
   908 void os::thread_local_storage_at_put(int index, void* value) {
   909   int rslt = pthread_setspecific((pthread_key_t)index, value);
   910   assert(rslt == 0, "pthread_setspecific failed");
   911 }
   913 extern "C" Thread* get_thread() {
   914   return ThreadLocalStorage::thread();
   915 }
   918 ////////////////////////////////////////////////////////////////////////////////
   919 // time support
   921 // Time since start-up in seconds to a fine granularity.
   922 // Used by VMSelfDestructTimer and the MemProfiler.
   923 double os::elapsedTime() {
   925   return (double)(os::elapsed_counter()) * 0.000001;
   926 }
   928 jlong os::elapsed_counter() {
   929   timeval time;
   930   int status = gettimeofday(&time, NULL);
   931   return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
   932 }
   934 jlong os::elapsed_frequency() {
   935   return (1000 * 1000);
   936 }
   938 // XXX: For now, code this as if BSD does not support vtime.
   939 bool os::supports_vtime() { return false; }
   940 bool os::enable_vtime()   { return false; }
   941 bool os::vtime_enabled()  { return false; }
   942 double os::elapsedVTime() {
   943   // better than nothing, but not much
   944   return elapsedTime();
   945 }
   947 jlong os::javaTimeMillis() {
   948   timeval time;
   949   int status = gettimeofday(&time, NULL);
   950   assert(status != -1, "bsd error");
   951   return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
   952 }
   954 #ifndef CLOCK_MONOTONIC
   955 #define CLOCK_MONOTONIC (1)
   956 #endif
   958 #ifdef __APPLE__
   959 void os::Bsd::clock_init() {
   960         // XXXDARWIN: Investigate replacement monotonic clock
   961 }
   962 #else
   963 void os::Bsd::clock_init() {
   964   struct timespec res;
   965   struct timespec tp;
   966   if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
   967       ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
   968     // yes, monotonic clock is supported
   969     _clock_gettime = ::clock_gettime;
   970   }
   971 }
   972 #endif
   975 jlong os::javaTimeNanos() {
   976   if (Bsd::supports_monotonic_clock()) {
   977     struct timespec tp;
   978     int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
   979     assert(status == 0, "gettime error");
   980     jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
   981     return result;
   982   } else {
   983     timeval time;
   984     int status = gettimeofday(&time, NULL);
   985     assert(status != -1, "bsd error");
   986     jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
   987     return 1000 * usecs;
   988   }
   989 }
   991 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
   992   if (Bsd::supports_monotonic_clock()) {
   993     info_ptr->max_value = ALL_64_BITS;
   995     // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
   996     info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
   997     info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
   998   } else {
   999     // gettimeofday - based on time in seconds since the Epoch thus does not wrap
  1000     info_ptr->max_value = ALL_64_BITS;
  1002     // gettimeofday is a real time clock so it skips
  1003     info_ptr->may_skip_backward = true;
  1004     info_ptr->may_skip_forward = true;
  1007   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
  1010 // Return the real, user, and system times in seconds from an
  1011 // arbitrary fixed point in the past.
  1012 bool os::getTimesSecs(double* process_real_time,
  1013                       double* process_user_time,
  1014                       double* process_system_time) {
  1015   struct tms ticks;
  1016   clock_t real_ticks = times(&ticks);
  1018   if (real_ticks == (clock_t) (-1)) {
  1019     return false;
  1020   } else {
  1021     double ticks_per_second = (double) clock_tics_per_sec;
  1022     *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
  1023     *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
  1024     *process_real_time = ((double) real_ticks) / ticks_per_second;
  1026     return true;
  1031 char * os::local_time_string(char *buf, size_t buflen) {
  1032   struct tm t;
  1033   time_t long_time;
  1034   time(&long_time);
  1035   localtime_r(&long_time, &t);
  1036   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
  1037                t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
  1038                t.tm_hour, t.tm_min, t.tm_sec);
  1039   return buf;
  1042 struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
  1043   return localtime_r(clock, res);
  1046 ////////////////////////////////////////////////////////////////////////////////
  1047 // runtime exit support
  1049 // Note: os::shutdown() might be called very early during initialization, or
  1050 // called from signal handler. Before adding something to os::shutdown(), make
  1051 // sure it is async-safe and can handle partially initialized VM.
  1052 void os::shutdown() {
  1054   // allow PerfMemory to attempt cleanup of any persistent resources
  1055   perfMemory_exit();
  1057   // needs to remove object in file system
  1058   AttachListener::abort();
  1060   // flush buffered output, finish log files
  1061   ostream_abort();
  1063   // Check for abort hook
  1064   abort_hook_t abort_hook = Arguments::abort_hook();
  1065   if (abort_hook != NULL) {
  1066     abort_hook();
  1071 // Note: os::abort() might be called very early during initialization, or
  1072 // called from signal handler. Before adding something to os::abort(), make
  1073 // sure it is async-safe and can handle partially initialized VM.
  1074 void os::abort(bool dump_core) {
  1075   os::shutdown();
  1076   if (dump_core) {
  1077 #ifndef PRODUCT
  1078     fdStream out(defaultStream::output_fd());
  1079     out.print_raw("Current thread is ");
  1080     char buf[16];
  1081     jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
  1082     out.print_raw_cr(buf);
  1083     out.print_raw_cr("Dumping core ...");
  1084 #endif
  1085     ::abort(); // dump core
  1088   ::exit(1);
  1091 // Die immediately, no exit hook, no abort hook, no cleanup.
  1092 void os::die() {
  1093   // _exit() on BsdThreads only kills current thread
  1094   ::abort();
  1097 // unused on bsd for now.
  1098 void os::set_error_file(const char *logfile) {}
  1101 // This method is a copy of JDK's sysGetLastErrorString
  1102 // from src/solaris/hpi/src/system_md.c
  1104 size_t os::lasterror(char *buf, size_t len) {
  1106   if (errno == 0)  return 0;
  1108   const char *s = ::strerror(errno);
  1109   size_t n = ::strlen(s);
  1110   if (n >= len) {
  1111     n = len - 1;
  1113   ::strncpy(buf, s, n);
  1114   buf[n] = '\0';
  1115   return n;
  1118 intx os::current_thread_id() {
  1119 #ifdef __APPLE__
  1120   return (intx)::mach_thread_self();
  1121 #else
  1122   return (intx)::pthread_self();
  1123 #endif
  1125 int os::current_process_id() {
  1127   // Under the old bsd thread library, bsd gives each thread
  1128   // its own process id. Because of this each thread will return
  1129   // a different pid if this method were to return the result
  1130   // of getpid(2). Bsd provides no api that returns the pid
  1131   // of the launcher thread for the vm. This implementation
  1132   // returns a unique pid, the pid of the launcher thread
  1133   // that starts the vm 'process'.
  1135   // Under the NPTL, getpid() returns the same pid as the
  1136   // launcher thread rather than a unique pid per thread.
  1137   // Use gettid() if you want the old pre NPTL behaviour.
  1139   // if you are looking for the result of a call to getpid() that
  1140   // returns a unique pid for the calling thread, then look at the
  1141   // OSThread::thread_id() method in osThread_bsd.hpp file
  1143   return (int)(_initial_pid ? _initial_pid : getpid());
  1146 // DLL functions
  1148 #define JNI_LIB_PREFIX "lib"
  1149 #ifdef __APPLE__
  1150 #define JNI_LIB_SUFFIX ".dylib"
  1151 #else
  1152 #define JNI_LIB_SUFFIX ".so"
  1153 #endif
  1155 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
  1157 // This must be hard coded because it's the system's temporary
  1158 // directory not the java application's temp directory, ala java.io.tmpdir.
  1159 #ifdef __APPLE__
  1160 // macosx has a secure per-user temporary directory
  1161 char temp_path_storage[PATH_MAX];
  1162 const char* os::get_temp_directory() {
  1163   static char *temp_path = NULL;
  1164   if (temp_path == NULL) {
  1165     int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
  1166     if (pathSize == 0 || pathSize > PATH_MAX) {
  1167       strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
  1169     temp_path = temp_path_storage;
  1171   return temp_path;
  1173 #else /* __APPLE__ */
  1174 const char* os::get_temp_directory() { return "/tmp"; }
  1175 #endif /* __APPLE__ */
  1177 static bool file_exists(const char* filename) {
  1178   struct stat statbuf;
  1179   if (filename == NULL || strlen(filename) == 0) {
  1180     return false;
  1182   return os::stat(filename, &statbuf) == 0;
  1185 bool os::dll_build_name(char* buffer, size_t buflen,
  1186                         const char* pname, const char* fname) {
  1187   bool retval = false;
  1188   // Copied from libhpi
  1189   const size_t pnamelen = pname ? strlen(pname) : 0;
  1191   // Return error on buffer overflow.
  1192   if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
  1193     return retval;
  1196   if (pnamelen == 0) {
  1197     snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
  1198     retval = true;
  1199   } else if (strchr(pname, *os::path_separator()) != NULL) {
  1200     int n;
  1201     char** pelements = split_path(pname, &n);
  1202     if (pelements == NULL) {
  1203       return false;
  1205     for (int i = 0 ; i < n ; i++) {
  1206       // Really shouldn't be NULL, but check can't hurt
  1207       if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
  1208         continue; // skip the empty path values
  1210       snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
  1211           pelements[i], fname);
  1212       if (file_exists(buffer)) {
  1213         retval = true;
  1214         break;
  1217     // release the storage
  1218     for (int i = 0 ; i < n ; i++) {
  1219       if (pelements[i] != NULL) {
  1220         FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
  1223     if (pelements != NULL) {
  1224       FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
  1226   } else {
  1227     snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
  1228     retval = true;
  1230   return retval;
  1233 const char* os::get_current_directory(char *buf, int buflen) {
  1234   return getcwd(buf, buflen);
  1237 // check if addr is inside libjvm.so
  1238 bool os::address_is_in_vm(address addr) {
  1239   static address libjvm_base_addr;
  1240   Dl_info dlinfo;
  1242   if (libjvm_base_addr == NULL) {
  1243     dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
  1244     libjvm_base_addr = (address)dlinfo.dli_fbase;
  1245     assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
  1248   if (dladdr((void *)addr, &dlinfo)) {
  1249     if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
  1252   return false;
  1256 #define MACH_MAXSYMLEN 256
  1258 bool os::dll_address_to_function_name(address addr, char *buf,
  1259                                       int buflen, int *offset) {
  1260   Dl_info dlinfo;
  1261   char localbuf[MACH_MAXSYMLEN];
  1263   // dladdr will find names of dynamic functions only, but does
  1264   // it set dli_fbase with mach_header address when it "fails" ?
  1265   if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
  1266     if (buf != NULL) {
  1267       if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
  1268         jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
  1271     if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
  1272     return true;
  1273   } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
  1274     if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
  1275        buf, buflen, offset, dlinfo.dli_fname)) {
  1276        return true;
  1280   // Handle non-dymanic manually:
  1281   if (dlinfo.dli_fbase != NULL &&
  1282       Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
  1283     if(!Decoder::demangle(localbuf, buf, buflen)) {
  1284       jio_snprintf(buf, buflen, "%s", localbuf);
  1286     return true;
  1288   if (buf != NULL) buf[0] = '\0';
  1289   if (offset != NULL) *offset = -1;
  1290   return false;
  1293 // ported from solaris version
  1294 bool os::dll_address_to_library_name(address addr, char* buf,
  1295                                      int buflen, int* offset) {
  1296   Dl_info dlinfo;
  1298   if (dladdr((void*)addr, &dlinfo)){
  1299      if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
  1300      if (offset) *offset = addr - (address)dlinfo.dli_fbase;
  1301      return true;
  1302   } else {
  1303      if (buf) buf[0] = '\0';
  1304      if (offset) *offset = -1;
  1305      return false;
  1309 // Loads .dll/.so and
  1310 // in case of error it checks if .dll/.so was built for the
  1311 // same architecture as Hotspot is running on
  1313 #ifdef __APPLE__
  1314 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
  1315   void * result= ::dlopen(filename, RTLD_LAZY);
  1316   if (result != NULL) {
  1317     // Successful loading
  1318     return result;
  1321   // Read system error message into ebuf
  1322   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1323   ebuf[ebuflen-1]='\0';
  1325   return NULL;
  1327 #else
  1328 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
  1330   void * result= ::dlopen(filename, RTLD_LAZY);
  1331   if (result != NULL) {
  1332     // Successful loading
  1333     return result;
  1336   Elf32_Ehdr elf_head;
  1338   // Read system error message into ebuf
  1339   // It may or may not be overwritten below
  1340   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1341   ebuf[ebuflen-1]='\0';
  1342   int diag_msg_max_length=ebuflen-strlen(ebuf);
  1343   char* diag_msg_buf=ebuf+strlen(ebuf);
  1345   if (diag_msg_max_length==0) {
  1346     // No more space in ebuf for additional diagnostics message
  1347     return NULL;
  1351   int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
  1353   if (file_descriptor < 0) {
  1354     // Can't open library, report dlerror() message
  1355     return NULL;
  1358   bool failed_to_read_elf_head=
  1359     (sizeof(elf_head)!=
  1360         (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
  1362   ::close(file_descriptor);
  1363   if (failed_to_read_elf_head) {
  1364     // file i/o error - report dlerror() msg
  1365     return NULL;
  1368   typedef struct {
  1369     Elf32_Half  code;         // Actual value as defined in elf.h
  1370     Elf32_Half  compat_class; // Compatibility of archs at VM's sense
  1371     char        elf_class;    // 32 or 64 bit
  1372     char        endianess;    // MSB or LSB
  1373     char*       name;         // String representation
  1374   } arch_t;
  1376   #ifndef EM_486
  1377   #define EM_486          6               /* Intel 80486 */
  1378   #endif
  1380   #ifndef EM_MIPS_RS3_LE
  1381   #define EM_MIPS_RS3_LE  10              /* MIPS */
  1382   #endif
  1384   #ifndef EM_PPC64
  1385   #define EM_PPC64        21              /* PowerPC64 */
  1386   #endif
  1388   #ifndef EM_S390
  1389   #define EM_S390         22              /* IBM System/390 */
  1390   #endif
  1392   #ifndef EM_IA_64
  1393   #define EM_IA_64        50              /* HP/Intel IA-64 */
  1394   #endif
  1396   #ifndef EM_X86_64
  1397   #define EM_X86_64       62              /* AMD x86-64 */
  1398   #endif
  1400   static const arch_t arch_array[]={
  1401     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1402     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1403     {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
  1404     {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
  1405     {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1406     {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1407     {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
  1408     {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
  1409     {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
  1410     {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
  1411     {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
  1412     {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
  1413     {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
  1414     {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
  1415     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
  1416     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
  1417   };
  1419   #if  (defined IA32)
  1420     static  Elf32_Half running_arch_code=EM_386;
  1421   #elif   (defined AMD64)
  1422     static  Elf32_Half running_arch_code=EM_X86_64;
  1423   #elif  (defined IA64)
  1424     static  Elf32_Half running_arch_code=EM_IA_64;
  1425   #elif  (defined __sparc) && (defined _LP64)
  1426     static  Elf32_Half running_arch_code=EM_SPARCV9;
  1427   #elif  (defined __sparc) && (!defined _LP64)
  1428     static  Elf32_Half running_arch_code=EM_SPARC;
  1429   #elif  (defined __powerpc64__)
  1430     static  Elf32_Half running_arch_code=EM_PPC64;
  1431   #elif  (defined __powerpc__)
  1432     static  Elf32_Half running_arch_code=EM_PPC;
  1433   #elif  (defined ARM)
  1434     static  Elf32_Half running_arch_code=EM_ARM;
  1435   #elif  (defined S390)
  1436     static  Elf32_Half running_arch_code=EM_S390;
  1437   #elif  (defined ALPHA)
  1438     static  Elf32_Half running_arch_code=EM_ALPHA;
  1439   #elif  (defined MIPSEL)
  1440     static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
  1441   #elif  (defined PARISC)
  1442     static  Elf32_Half running_arch_code=EM_PARISC;
  1443   #elif  (defined MIPS)
  1444     static  Elf32_Half running_arch_code=EM_MIPS;
  1445   #elif  (defined M68K)
  1446     static  Elf32_Half running_arch_code=EM_68K;
  1447   #else
  1448     #error Method os::dll_load requires that one of following is defined:\
  1449          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
  1450   #endif
  1452   // Identify compatability class for VM's architecture and library's architecture
  1453   // Obtain string descriptions for architectures
  1455   arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
  1456   int running_arch_index=-1;
  1458   for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
  1459     if (running_arch_code == arch_array[i].code) {
  1460       running_arch_index    = i;
  1462     if (lib_arch.code == arch_array[i].code) {
  1463       lib_arch.compat_class = arch_array[i].compat_class;
  1464       lib_arch.name         = arch_array[i].name;
  1468   assert(running_arch_index != -1,
  1469     "Didn't find running architecture code (running_arch_code) in arch_array");
  1470   if (running_arch_index == -1) {
  1471     // Even though running architecture detection failed
  1472     // we may still continue with reporting dlerror() message
  1473     return NULL;
  1476   if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
  1477     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
  1478     return NULL;
  1481 #ifndef S390
  1482   if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
  1483     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
  1484     return NULL;
  1486 #endif // !S390
  1488   if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
  1489     if ( lib_arch.name!=NULL ) {
  1490       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1491         " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
  1492         lib_arch.name, arch_array[running_arch_index].name);
  1493     } else {
  1494       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1495       " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
  1496         lib_arch.code,
  1497         arch_array[running_arch_index].name);
  1501   return NULL;
  1503 #endif /* !__APPLE__ */
  1505 // XXX: Do we need a lock around this as per Linux?
  1506 void* os::dll_lookup(void* handle, const char* name) {
  1507   return dlsym(handle, name);
  1511 static bool _print_ascii_file(const char* filename, outputStream* st) {
  1512   int fd = ::open(filename, O_RDONLY);
  1513   if (fd == -1) {
  1514      return false;
  1517   char buf[32];
  1518   int bytes;
  1519   while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
  1520     st->print_raw(buf, bytes);
  1523   ::close(fd);
  1525   return true;
  1528 void os::print_dll_info(outputStream *st) {
  1529    st->print_cr("Dynamic libraries:");
  1530 #ifdef RTLD_DI_LINKMAP
  1531     Dl_info dli;
  1532     void *handle;
  1533     Link_map *map;
  1534     Link_map *p;
  1536     if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
  1537         st->print_cr("Error: Cannot print dynamic libraries.");
  1538         return;
  1540     handle = dlopen(dli.dli_fname, RTLD_LAZY);
  1541     if (handle == NULL) {
  1542         st->print_cr("Error: Cannot print dynamic libraries.");
  1543         return;
  1545     dlinfo(handle, RTLD_DI_LINKMAP, &map);
  1546     if (map == NULL) {
  1547         st->print_cr("Error: Cannot print dynamic libraries.");
  1548         return;
  1551     while (map->l_prev != NULL)
  1552         map = map->l_prev;
  1554     while (map != NULL) {
  1555         st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
  1556         map = map->l_next;
  1559     dlclose(handle);
  1560 #elif defined(__APPLE__)
  1561     uint32_t count;
  1562     uint32_t i;
  1564     count = _dyld_image_count();
  1565     for (i = 1; i < count; i++) {
  1566         const char *name = _dyld_get_image_name(i);
  1567         intptr_t slide = _dyld_get_image_vmaddr_slide(i);
  1568         st->print_cr(PTR_FORMAT " \t%s", slide, name);
  1570 #else
  1571    st->print_cr("Error: Cannot print dynamic libraries.");
  1572 #endif
  1575 void os::print_os_info_brief(outputStream* st) {
  1576   st->print("Bsd");
  1578   os::Posix::print_uname_info(st);
  1581 void os::print_os_info(outputStream* st) {
  1582   st->print("OS:");
  1583   st->print("Bsd");
  1585   os::Posix::print_uname_info(st);
  1587   os::Posix::print_rlimit_info(st);
  1589   os::Posix::print_load_average(st);
  1592 void os::pd_print_cpu_info(outputStream* st) {
  1593   // Nothing to do for now.
  1596 void os::print_memory_info(outputStream* st) {
  1598   st->print("Memory:");
  1599   st->print(" %dk page", os::vm_page_size()>>10);
  1601   st->print(", physical " UINT64_FORMAT "k",
  1602             os::physical_memory() >> 10);
  1603   st->print("(" UINT64_FORMAT "k free)",
  1604             os::available_memory() >> 10);
  1605   st->cr();
  1607   // meminfo
  1608   st->print("\n/proc/meminfo:\n");
  1609   _print_ascii_file("/proc/meminfo", st);
  1610   st->cr();
  1613 // Taken from /usr/include/bits/siginfo.h  Supposed to be architecture specific
  1614 // but they're the same for all the bsd arch that we support
  1615 // and they're the same for solaris but there's no common place to put this.
  1616 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
  1617                           "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
  1618                           "ILL_COPROC", "ILL_BADSTK" };
  1620 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
  1621                           "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
  1622                           "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
  1624 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
  1626 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
  1628 void os::print_siginfo(outputStream* st, void* siginfo) {
  1629   st->print("siginfo:");
  1631   const int buflen = 100;
  1632   char buf[buflen];
  1633   siginfo_t *si = (siginfo_t*)siginfo;
  1634   st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
  1635   if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
  1636     st->print("si_errno=%s", buf);
  1637   } else {
  1638     st->print("si_errno=%d", si->si_errno);
  1640   const int c = si->si_code;
  1641   assert(c > 0, "unexpected si_code");
  1642   switch (si->si_signo) {
  1643   case SIGILL:
  1644     st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
  1645     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1646     break;
  1647   case SIGFPE:
  1648     st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
  1649     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1650     break;
  1651   case SIGSEGV:
  1652     st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
  1653     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1654     break;
  1655   case SIGBUS:
  1656     st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
  1657     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1658     break;
  1659   default:
  1660     st->print(", si_code=%d", si->si_code);
  1661     // no si_addr
  1664   if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
  1665       UseSharedSpaces) {
  1666     FileMapInfo* mapinfo = FileMapInfo::current_info();
  1667     if (mapinfo->is_in_shared_space(si->si_addr)) {
  1668       st->print("\n\nError accessing class data sharing archive."   \
  1669                 " Mapped file inaccessible during execution, "      \
  1670                 " possible disk/network problem.");
  1673   st->cr();
  1677 static void print_signal_handler(outputStream* st, int sig,
  1678                                  char* buf, size_t buflen);
  1680 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
  1681   st->print_cr("Signal Handlers:");
  1682   print_signal_handler(st, SIGSEGV, buf, buflen);
  1683   print_signal_handler(st, SIGBUS , buf, buflen);
  1684   print_signal_handler(st, SIGFPE , buf, buflen);
  1685   print_signal_handler(st, SIGPIPE, buf, buflen);
  1686   print_signal_handler(st, SIGXFSZ, buf, buflen);
  1687   print_signal_handler(st, SIGILL , buf, buflen);
  1688   print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
  1689   print_signal_handler(st, SR_signum, buf, buflen);
  1690   print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
  1691   print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
  1692   print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
  1693   print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
  1696 static char saved_jvm_path[MAXPATHLEN] = {0};
  1698 // Find the full path to the current module, libjvm
  1699 void os::jvm_path(char *buf, jint buflen) {
  1700   // Error checking.
  1701   if (buflen < MAXPATHLEN) {
  1702     assert(false, "must use a large-enough buffer");
  1703     buf[0] = '\0';
  1704     return;
  1706   // Lazy resolve the path to current module.
  1707   if (saved_jvm_path[0] != 0) {
  1708     strcpy(buf, saved_jvm_path);
  1709     return;
  1712   char dli_fname[MAXPATHLEN];
  1713   bool ret = dll_address_to_library_name(
  1714                 CAST_FROM_FN_PTR(address, os::jvm_path),
  1715                 dli_fname, sizeof(dli_fname), NULL);
  1716   assert(ret != 0, "cannot locate libjvm");
  1717   char *rp = realpath(dli_fname, buf);
  1718   if (rp == NULL)
  1719     return;
  1721   if (Arguments::created_by_gamma_launcher()) {
  1722     // Support for the gamma launcher.  Typical value for buf is
  1723     // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm".  If "/jre/lib/" appears at
  1724     // the right place in the string, then assume we are installed in a JDK and
  1725     // we're done.  Otherwise, check for a JAVA_HOME environment variable and
  1726     // construct a path to the JVM being overridden.
  1728     const char *p = buf + strlen(buf) - 1;
  1729     for (int count = 0; p > buf && count < 5; ++count) {
  1730       for (--p; p > buf && *p != '/'; --p)
  1731         /* empty */ ;
  1734     if (strncmp(p, "/jre/lib/", 9) != 0) {
  1735       // Look for JAVA_HOME in the environment.
  1736       char* java_home_var = ::getenv("JAVA_HOME");
  1737       if (java_home_var != NULL && java_home_var[0] != 0) {
  1738         char* jrelib_p;
  1739         int len;
  1741         // Check the current module name "libjvm"
  1742         p = strrchr(buf, '/');
  1743         assert(strstr(p, "/libjvm") == p, "invalid library name");
  1745         rp = realpath(java_home_var, buf);
  1746         if (rp == NULL)
  1747           return;
  1749         // determine if this is a legacy image or modules image
  1750         // modules image doesn't have "jre" subdirectory
  1751         len = strlen(buf);
  1752         jrelib_p = buf + len;
  1754         // Add the appropriate library subdir
  1755         snprintf(jrelib_p, buflen-len, "/jre/lib");
  1756         if (0 != access(buf, F_OK)) {
  1757           snprintf(jrelib_p, buflen-len, "/lib");
  1760         // Add the appropriate client or server subdir
  1761         len = strlen(buf);
  1762         jrelib_p = buf + len;
  1763         snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
  1764         if (0 != access(buf, F_OK)) {
  1765           snprintf(jrelib_p, buflen-len, "");
  1768         // If the path exists within JAVA_HOME, add the JVM library name
  1769         // to complete the path to JVM being overridden.  Otherwise fallback
  1770         // to the path to the current library.
  1771         if (0 == access(buf, F_OK)) {
  1772           // Use current module name "libjvm"
  1773           len = strlen(buf);
  1774           snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
  1775         } else {
  1776           // Fall back to path of current library
  1777           rp = realpath(dli_fname, buf);
  1778           if (rp == NULL)
  1779             return;
  1785   strcpy(saved_jvm_path, buf);
  1788 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
  1789   // no prefix required, not even "_"
  1792 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
  1793   // no suffix required
  1796 ////////////////////////////////////////////////////////////////////////////////
  1797 // sun.misc.Signal support
  1799 static volatile jint sigint_count = 0;
  1801 static void
  1802 UserHandler(int sig, void *siginfo, void *context) {
  1803   // 4511530 - sem_post is serialized and handled by the manager thread. When
  1804   // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
  1805   // don't want to flood the manager thread with sem_post requests.
  1806   if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
  1807       return;
  1809   // Ctrl-C is pressed during error reporting, likely because the error
  1810   // handler fails to abort. Let VM die immediately.
  1811   if (sig == SIGINT && is_error_reported()) {
  1812      os::die();
  1815   os::signal_notify(sig);
  1818 void* os::user_handler() {
  1819   return CAST_FROM_FN_PTR(void*, UserHandler);
  1822 extern "C" {
  1823   typedef void (*sa_handler_t)(int);
  1824   typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
  1827 void* os::signal(int signal_number, void* handler) {
  1828   struct sigaction sigAct, oldSigAct;
  1830   sigfillset(&(sigAct.sa_mask));
  1831   sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
  1832   sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
  1834   if (sigaction(signal_number, &sigAct, &oldSigAct)) {
  1835     // -1 means registration failed
  1836     return (void *)-1;
  1839   return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
  1842 void os::signal_raise(int signal_number) {
  1843   ::raise(signal_number);
  1846 /*
  1847  * The following code is moved from os.cpp for making this
  1848  * code platform specific, which it is by its very nature.
  1849  */
  1851 // Will be modified when max signal is changed to be dynamic
  1852 int os::sigexitnum_pd() {
  1853   return NSIG;
  1856 // a counter for each possible signal value
  1857 static volatile jint pending_signals[NSIG+1] = { 0 };
  1859 // Bsd(POSIX) specific hand shaking semaphore.
  1860 #ifdef __APPLE__
  1861 static semaphore_t sig_sem;
  1862 #define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
  1863 #define SEM_WAIT(sem)           semaphore_wait(sem);
  1864 #define SEM_POST(sem)           semaphore_signal(sem);
  1865 #else
  1866 static sem_t sig_sem;
  1867 #define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
  1868 #define SEM_WAIT(sem)           sem_wait(&sem);
  1869 #define SEM_POST(sem)           sem_post(&sem);
  1870 #endif
  1872 void os::signal_init_pd() {
  1873   // Initialize signal structures
  1874   ::memset((void*)pending_signals, 0, sizeof(pending_signals));
  1876   // Initialize signal semaphore
  1877   ::SEM_INIT(sig_sem, 0);
  1880 void os::signal_notify(int sig) {
  1881   Atomic::inc(&pending_signals[sig]);
  1882   ::SEM_POST(sig_sem);
  1885 static int check_pending_signals(bool wait) {
  1886   Atomic::store(0, &sigint_count);
  1887   for (;;) {
  1888     for (int i = 0; i < NSIG + 1; i++) {
  1889       jint n = pending_signals[i];
  1890       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
  1891         return i;
  1894     if (!wait) {
  1895       return -1;
  1897     JavaThread *thread = JavaThread::current();
  1898     ThreadBlockInVM tbivm(thread);
  1900     bool threadIsSuspended;
  1901     do {
  1902       thread->set_suspend_equivalent();
  1903       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  1904       ::SEM_WAIT(sig_sem);
  1906       // were we externally suspended while we were waiting?
  1907       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
  1908       if (threadIsSuspended) {
  1909         //
  1910         // The semaphore has been incremented, but while we were waiting
  1911         // another thread suspended us. We don't want to continue running
  1912         // while suspended because that would surprise the thread that
  1913         // suspended us.
  1914         //
  1915         ::SEM_POST(sig_sem);
  1917         thread->java_suspend_self();
  1919     } while (threadIsSuspended);
  1923 int os::signal_lookup() {
  1924   return check_pending_signals(false);
  1927 int os::signal_wait() {
  1928   return check_pending_signals(true);
  1931 ////////////////////////////////////////////////////////////////////////////////
  1932 // Virtual Memory
  1934 int os::vm_page_size() {
  1935   // Seems redundant as all get out
  1936   assert(os::Bsd::page_size() != -1, "must call os::init");
  1937   return os::Bsd::page_size();
  1940 // Solaris allocates memory by pages.
  1941 int os::vm_allocation_granularity() {
  1942   assert(os::Bsd::page_size() != -1, "must call os::init");
  1943   return os::Bsd::page_size();
  1946 // Rationale behind this function:
  1947 //  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
  1948 //  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
  1949 //  samples for JITted code. Here we create private executable mapping over the code cache
  1950 //  and then we can use standard (well, almost, as mapping can change) way to provide
  1951 //  info for the reporting script by storing timestamp and location of symbol
  1952 void bsd_wrap_code(char* base, size_t size) {
  1953   static volatile jint cnt = 0;
  1955   if (!UseOprofile) {
  1956     return;
  1959   char buf[PATH_MAX + 1];
  1960   int num = Atomic::add(1, &cnt);
  1962   snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
  1963            os::get_temp_directory(), os::current_process_id(), num);
  1964   unlink(buf);
  1966   int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
  1968   if (fd != -1) {
  1969     off_t rv = ::lseek(fd, size-2, SEEK_SET);
  1970     if (rv != (off_t)-1) {
  1971       if (::write(fd, "", 1) == 1) {
  1972         mmap(base, size,
  1973              PROT_READ|PROT_WRITE|PROT_EXEC,
  1974              MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
  1977     ::close(fd);
  1978     unlink(buf);
  1982 // NOTE: Bsd kernel does not really reserve the pages for us.
  1983 //       All it does is to check if there are enough free pages
  1984 //       left at the time of mmap(). This could be a potential
  1985 //       problem.
  1986 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
  1987   int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
  1988 #ifdef __OpenBSD__
  1989   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  1990   return ::mprotect(addr, size, prot) == 0;
  1991 #else
  1992   uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
  1993                                    MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
  1994   return res != (uintptr_t) MAP_FAILED;
  1995 #endif
  1999 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
  2000                        bool exec) {
  2001   return commit_memory(addr, size, exec);
  2004 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2007 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2008   ::madvise(addr, bytes, MADV_DONTNEED);
  2011 void os::numa_make_global(char *addr, size_t bytes) {
  2014 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
  2017 bool os::numa_topology_changed()   { return false; }
  2019 size_t os::numa_get_groups_num() {
  2020   return 1;
  2023 int os::numa_get_group_id() {
  2024   return 0;
  2027 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
  2028   if (size > 0) {
  2029     ids[0] = 0;
  2030     return 1;
  2032   return 0;
  2035 bool os::get_page_info(char *start, page_info* info) {
  2036   return false;
  2039 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
  2040   return end;
  2044 bool os::pd_uncommit_memory(char* addr, size_t size) {
  2045 #ifdef __OpenBSD__
  2046   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  2047   return ::mprotect(addr, size, PROT_NONE) == 0;
  2048 #else
  2049   uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
  2050                 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
  2051   return res  != (uintptr_t) MAP_FAILED;
  2052 #endif
  2055 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
  2056   return os::commit_memory(addr, size);
  2059 // If this is a growable mapping, remove the guard pages entirely by
  2060 // munmap()ping them.  If not, just call uncommit_memory().
  2061 bool os::remove_stack_guard_pages(char* addr, size_t size) {
  2062   return os::uncommit_memory(addr, size);
  2065 static address _highest_vm_reserved_address = NULL;
  2067 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
  2068 // at 'requested_addr'. If there are existing memory mappings at the same
  2069 // location, however, they will be overwritten. If 'fixed' is false,
  2070 // 'requested_addr' is only treated as a hint, the return value may or
  2071 // may not start from the requested address. Unlike Bsd mmap(), this
  2072 // function returns NULL to indicate failure.
  2073 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
  2074   char * addr;
  2075   int flags;
  2077   flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
  2078   if (fixed) {
  2079     assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
  2080     flags |= MAP_FIXED;
  2083   // Map uncommitted pages PROT_READ and PROT_WRITE, change access
  2084   // to PROT_EXEC if executable when we commit the page.
  2085   addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
  2086                        flags, -1, 0);
  2088   if (addr != MAP_FAILED) {
  2089     // anon_mmap() should only get called during VM initialization,
  2090     // don't need lock (actually we can skip locking even it can be called
  2091     // from multiple threads, because _highest_vm_reserved_address is just a
  2092     // hint about the upper limit of non-stack memory regions.)
  2093     if ((address)addr + bytes > _highest_vm_reserved_address) {
  2094       _highest_vm_reserved_address = (address)addr + bytes;
  2098   return addr == MAP_FAILED ? NULL : addr;
  2101 // Don't update _highest_vm_reserved_address, because there might be memory
  2102 // regions above addr + size. If so, releasing a memory region only creates
  2103 // a hole in the address space, it doesn't help prevent heap-stack collision.
  2104 //
  2105 static int anon_munmap(char * addr, size_t size) {
  2106   return ::munmap(addr, size) == 0;
  2109 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
  2110                          size_t alignment_hint) {
  2111   return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
  2114 bool os::pd_release_memory(char* addr, size_t size) {
  2115   return anon_munmap(addr, size);
  2118 static address highest_vm_reserved_address() {
  2119   return _highest_vm_reserved_address;
  2122 static bool bsd_mprotect(char* addr, size_t size, int prot) {
  2123   // Bsd wants the mprotect address argument to be page aligned.
  2124   char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
  2126   // According to SUSv3, mprotect() should only be used with mappings
  2127   // established by mmap(), and mmap() always maps whole pages. Unaligned
  2128   // 'addr' likely indicates problem in the VM (e.g. trying to change
  2129   // protection of malloc'ed or statically allocated memory). Check the
  2130   // caller if you hit this assert.
  2131   assert(addr == bottom, "sanity check");
  2133   size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
  2134   return ::mprotect(bottom, size, prot) == 0;
  2137 // Set protections specified
  2138 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
  2139                         bool is_committed) {
  2140   unsigned int p = 0;
  2141   switch (prot) {
  2142   case MEM_PROT_NONE: p = PROT_NONE; break;
  2143   case MEM_PROT_READ: p = PROT_READ; break;
  2144   case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
  2145   case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
  2146   default:
  2147     ShouldNotReachHere();
  2149   // is_committed is unused.
  2150   return bsd_mprotect(addr, bytes, p);
  2153 bool os::guard_memory(char* addr, size_t size) {
  2154   return bsd_mprotect(addr, size, PROT_NONE);
  2157 bool os::unguard_memory(char* addr, size_t size) {
  2158   return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
  2161 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
  2162   return false;
  2165 /*
  2166 * Set the coredump_filter bits to include largepages in core dump (bit 6)
  2168 * From the coredump_filter documentation:
  2170 * - (bit 0) anonymous private memory
  2171 * - (bit 1) anonymous shared memory
  2172 * - (bit 2) file-backed private memory
  2173 * - (bit 3) file-backed shared memory
  2174 * - (bit 4) ELF header pages in file-backed private memory areas (it is
  2175 *           effective only if the bit 2 is cleared)
  2176 * - (bit 5) hugetlb private memory
  2177 * - (bit 6) hugetlb shared memory
  2178 */
  2179 static void set_coredump_filter(void) {
  2180   FILE *f;
  2181   long cdm;
  2183   if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
  2184     return;
  2187   if (fscanf(f, "%lx", &cdm) != 1) {
  2188     fclose(f);
  2189     return;
  2192   rewind(f);
  2194   if ((cdm & LARGEPAGES_BIT) == 0) {
  2195     cdm |= LARGEPAGES_BIT;
  2196     fprintf(f, "%#lx", cdm);
  2199   fclose(f);
  2202 // Large page support
  2204 static size_t _large_page_size = 0;
  2206 void os::large_page_init() {
  2210 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
  2211   // "exec" is passed in but not used.  Creating the shared image for
  2212   // the code cache doesn't have an SHM_X executable permission to check.
  2213   assert(UseLargePages && UseSHM, "only for SHM large pages");
  2215   key_t key = IPC_PRIVATE;
  2216   char *addr;
  2218   bool warn_on_failure = UseLargePages &&
  2219                         (!FLAG_IS_DEFAULT(UseLargePages) ||
  2220                          !FLAG_IS_DEFAULT(LargePageSizeInBytes)
  2221                         );
  2222   char msg[128];
  2224   // Create a large shared memory region to attach to based on size.
  2225   // Currently, size is the total size of the heap
  2226   int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
  2227   if (shmid == -1) {
  2228      // Possible reasons for shmget failure:
  2229      // 1. shmmax is too small for Java heap.
  2230      //    > check shmmax value: cat /proc/sys/kernel/shmmax
  2231      //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
  2232      // 2. not enough large page memory.
  2233      //    > check available large pages: cat /proc/meminfo
  2234      //    > increase amount of large pages:
  2235      //          echo new_value > /proc/sys/vm/nr_hugepages
  2236      //      Note 1: different Bsd may use different name for this property,
  2237      //            e.g. on Redhat AS-3 it is "hugetlb_pool".
  2238      //      Note 2: it's possible there's enough physical memory available but
  2239      //            they are so fragmented after a long run that they can't
  2240      //            coalesce into large pages. Try to reserve large pages when
  2241      //            the system is still "fresh".
  2242      if (warn_on_failure) {
  2243        jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
  2244        warning(msg);
  2246      return NULL;
  2249   // attach to the region
  2250   addr = (char*)shmat(shmid, req_addr, 0);
  2251   int err = errno;
  2253   // Remove shmid. If shmat() is successful, the actual shared memory segment
  2254   // will be deleted when it's detached by shmdt() or when the process
  2255   // terminates. If shmat() is not successful this will remove the shared
  2256   // segment immediately.
  2257   shmctl(shmid, IPC_RMID, NULL);
  2259   if ((intptr_t)addr == -1) {
  2260      if (warn_on_failure) {
  2261        jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
  2262        warning(msg);
  2264      return NULL;
  2267   // The memory is committed
  2268   address pc = CALLER_PC;
  2269   MemTracker::record_virtual_memory_reserve((address)addr, bytes, pc);
  2270   MemTracker::record_virtual_memory_commit((address)addr, bytes, pc);
  2272   return addr;
  2275 bool os::release_memory_special(char* base, size_t bytes) {
  2276   // detaching the SHM segment will also delete it, see reserve_memory_special()
  2277   int rslt = shmdt(base);
  2278   if (rslt == 0) {
  2279     MemTracker::record_virtual_memory_uncommit((address)base, bytes);
  2280     MemTracker::record_virtual_memory_release((address)base, bytes);
  2281     return true;
  2282   } else {
  2283     return false;
  2288 size_t os::large_page_size() {
  2289   return _large_page_size;
  2292 // HugeTLBFS allows application to commit large page memory on demand;
  2293 // with SysV SHM the entire memory region must be allocated as shared
  2294 // memory.
  2295 bool os::can_commit_large_page_memory() {
  2296   return UseHugeTLBFS;
  2299 bool os::can_execute_large_page_memory() {
  2300   return UseHugeTLBFS;
  2303 // Reserve memory at an arbitrary address, only if that area is
  2304 // available (and not reserved for something else).
  2306 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
  2307   const int max_tries = 10;
  2308   char* base[max_tries];
  2309   size_t size[max_tries];
  2310   const size_t gap = 0x000000;
  2312   // Assert only that the size is a multiple of the page size, since
  2313   // that's all that mmap requires, and since that's all we really know
  2314   // about at this low abstraction level.  If we need higher alignment,
  2315   // we can either pass an alignment to this method or verify alignment
  2316   // in one of the methods further up the call chain.  See bug 5044738.
  2317   assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
  2319   // Repeatedly allocate blocks until the block is allocated at the
  2320   // right spot. Give up after max_tries. Note that reserve_memory() will
  2321   // automatically update _highest_vm_reserved_address if the call is
  2322   // successful. The variable tracks the highest memory address every reserved
  2323   // by JVM. It is used to detect heap-stack collision if running with
  2324   // fixed-stack BsdThreads. Because here we may attempt to reserve more
  2325   // space than needed, it could confuse the collision detecting code. To
  2326   // solve the problem, save current _highest_vm_reserved_address and
  2327   // calculate the correct value before return.
  2328   address old_highest = _highest_vm_reserved_address;
  2330   // Bsd mmap allows caller to pass an address as hint; give it a try first,
  2331   // if kernel honors the hint then we can return immediately.
  2332   char * addr = anon_mmap(requested_addr, bytes, false);
  2333   if (addr == requested_addr) {
  2334      return requested_addr;
  2337   if (addr != NULL) {
  2338      // mmap() is successful but it fails to reserve at the requested address
  2339      anon_munmap(addr, bytes);
  2342   int i;
  2343   for (i = 0; i < max_tries; ++i) {
  2344     base[i] = reserve_memory(bytes);
  2346     if (base[i] != NULL) {
  2347       // Is this the block we wanted?
  2348       if (base[i] == requested_addr) {
  2349         size[i] = bytes;
  2350         break;
  2353       // Does this overlap the block we wanted? Give back the overlapped
  2354       // parts and try again.
  2356       size_t top_overlap = requested_addr + (bytes + gap) - base[i];
  2357       if (top_overlap >= 0 && top_overlap < bytes) {
  2358         unmap_memory(base[i], top_overlap);
  2359         base[i] += top_overlap;
  2360         size[i] = bytes - top_overlap;
  2361       } else {
  2362         size_t bottom_overlap = base[i] + bytes - requested_addr;
  2363         if (bottom_overlap >= 0 && bottom_overlap < bytes) {
  2364           unmap_memory(requested_addr, bottom_overlap);
  2365           size[i] = bytes - bottom_overlap;
  2366         } else {
  2367           size[i] = bytes;
  2373   // Give back the unused reserved pieces.
  2375   for (int j = 0; j < i; ++j) {
  2376     if (base[j] != NULL) {
  2377       unmap_memory(base[j], size[j]);
  2381   if (i < max_tries) {
  2382     _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
  2383     return requested_addr;
  2384   } else {
  2385     _highest_vm_reserved_address = old_highest;
  2386     return NULL;
  2390 size_t os::read(int fd, void *buf, unsigned int nBytes) {
  2391   RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
  2394 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
  2395 // Solaris uses poll(), bsd uses park().
  2396 // Poll() is likely a better choice, assuming that Thread.interrupt()
  2397 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
  2398 // SIGSEGV, see 4355769.
  2400 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
  2401   assert(thread == Thread::current(),  "thread consistency check");
  2403   ParkEvent * const slp = thread->_SleepEvent ;
  2404   slp->reset() ;
  2405   OrderAccess::fence() ;
  2407   if (interruptible) {
  2408     jlong prevtime = javaTimeNanos();
  2410     for (;;) {
  2411       if (os::is_interrupted(thread, true)) {
  2412         return OS_INTRPT;
  2415       jlong newtime = javaTimeNanos();
  2417       if (newtime - prevtime < 0) {
  2418         // time moving backwards, should only happen if no monotonic clock
  2419         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2420         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2421       } else {
  2422         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2425       if(millis <= 0) {
  2426         return OS_OK;
  2429       prevtime = newtime;
  2432         assert(thread->is_Java_thread(), "sanity check");
  2433         JavaThread *jt = (JavaThread *) thread;
  2434         ThreadBlockInVM tbivm(jt);
  2435         OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
  2437         jt->set_suspend_equivalent();
  2438         // cleared by handle_special_suspend_equivalent_condition() or
  2439         // java_suspend_self() via check_and_wait_while_suspended()
  2441         slp->park(millis);
  2443         // were we externally suspended while we were waiting?
  2444         jt->check_and_wait_while_suspended();
  2447   } else {
  2448     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  2449     jlong prevtime = javaTimeNanos();
  2451     for (;;) {
  2452       // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
  2453       // the 1st iteration ...
  2454       jlong newtime = javaTimeNanos();
  2456       if (newtime - prevtime < 0) {
  2457         // time moving backwards, should only happen if no monotonic clock
  2458         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2459         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2460       } else {
  2461         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2464       if(millis <= 0) break ;
  2466       prevtime = newtime;
  2467       slp->park(millis);
  2469     return OS_OK ;
  2473 int os::naked_sleep() {
  2474   // %% make the sleep time an integer flag. for now use 1 millisec.
  2475   return os::sleep(Thread::current(), 1, false);
  2478 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
  2479 void os::infinite_sleep() {
  2480   while (true) {    // sleep forever ...
  2481     ::sleep(100);   // ... 100 seconds at a time
  2485 // Used to convert frequent JVM_Yield() to nops
  2486 bool os::dont_yield() {
  2487   return DontYieldALot;
  2490 void os::yield() {
  2491   sched_yield();
  2494 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
  2496 void os::yield_all(int attempts) {
  2497   // Yields to all threads, including threads with lower priorities
  2498   // Threads on Bsd are all with same priority. The Solaris style
  2499   // os::yield_all() with nanosleep(1ms) is not necessary.
  2500   sched_yield();
  2503 // Called from the tight loops to possibly influence time-sharing heuristics
  2504 void os::loop_breaker(int attempts) {
  2505   os::yield_all(attempts);
  2508 ////////////////////////////////////////////////////////////////////////////////
  2509 // thread priority support
  2511 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
  2512 // only supports dynamic priority, static priority must be zero. For real-time
  2513 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
  2514 // However, for large multi-threaded applications, SCHED_RR is not only slower
  2515 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
  2516 // of 5 runs - Sep 2005).
  2517 //
  2518 // The following code actually changes the niceness of kernel-thread/LWP. It
  2519 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
  2520 // not the entire user process, and user level threads are 1:1 mapped to kernel
  2521 // threads. It has always been the case, but could change in the future. For
  2522 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
  2523 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
  2525 #if !defined(__APPLE__)
  2526 int os::java_to_os_priority[CriticalPriority + 1] = {
  2527   19,              // 0 Entry should never be used
  2529    0,              // 1 MinPriority
  2530    3,              // 2
  2531    6,              // 3
  2533   10,              // 4
  2534   15,              // 5 NormPriority
  2535   18,              // 6
  2537   21,              // 7
  2538   25,              // 8
  2539   28,              // 9 NearMaxPriority
  2541   31,              // 10 MaxPriority
  2543   31               // 11 CriticalPriority
  2544 };
  2545 #else
  2546 /* Using Mach high-level priority assignments */
  2547 int os::java_to_os_priority[CriticalPriority + 1] = {
  2548    0,              // 0 Entry should never be used (MINPRI_USER)
  2550   27,              // 1 MinPriority
  2551   28,              // 2
  2552   29,              // 3
  2554   30,              // 4
  2555   31,              // 5 NormPriority (BASEPRI_DEFAULT)
  2556   32,              // 6
  2558   33,              // 7
  2559   34,              // 8
  2560   35,              // 9 NearMaxPriority
  2562   36,              // 10 MaxPriority
  2564   36               // 11 CriticalPriority
  2565 };
  2566 #endif
  2568 static int prio_init() {
  2569   if (ThreadPriorityPolicy == 1) {
  2570     // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
  2571     // if effective uid is not root. Perhaps, a more elegant way of doing
  2572     // this is to test CAP_SYS_NICE capability, but that will require libcap.so
  2573     if (geteuid() != 0) {
  2574       if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
  2575         warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
  2577       ThreadPriorityPolicy = 0;
  2580   if (UseCriticalJavaThreadPriority) {
  2581     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
  2583   return 0;
  2586 OSReturn os::set_native_priority(Thread* thread, int newpri) {
  2587   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
  2589 #ifdef __OpenBSD__
  2590   // OpenBSD pthread_setprio starves low priority threads
  2591   return OS_OK;
  2592 #elif defined(__FreeBSD__)
  2593   int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
  2594 #elif defined(__APPLE__) || defined(__NetBSD__)
  2595   struct sched_param sp;
  2596   int policy;
  2597   pthread_t self = pthread_self();
  2599   if (pthread_getschedparam(self, &policy, &sp) != 0)
  2600     return OS_ERR;
  2602   sp.sched_priority = newpri;
  2603   if (pthread_setschedparam(self, policy, &sp) != 0)
  2604     return OS_ERR;
  2606   return OS_OK;
  2607 #else
  2608   int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
  2609   return (ret == 0) ? OS_OK : OS_ERR;
  2610 #endif
  2613 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
  2614   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
  2615     *priority_ptr = java_to_os_priority[NormPriority];
  2616     return OS_OK;
  2619   errno = 0;
  2620 #if defined(__OpenBSD__) || defined(__FreeBSD__)
  2621   *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
  2622 #elif defined(__APPLE__) || defined(__NetBSD__)
  2623   int policy;
  2624   struct sched_param sp;
  2626   pthread_getschedparam(pthread_self(), &policy, &sp);
  2627   *priority_ptr = sp.sched_priority;
  2628 #else
  2629   *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
  2630 #endif
  2631   return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
  2634 // Hint to the underlying OS that a task switch would not be good.
  2635 // Void return because it's a hint and can fail.
  2636 void os::hint_no_preempt() {}
  2638 ////////////////////////////////////////////////////////////////////////////////
  2639 // suspend/resume support
  2641 //  the low-level signal-based suspend/resume support is a remnant from the
  2642 //  old VM-suspension that used to be for java-suspension, safepoints etc,
  2643 //  within hotspot. Now there is a single use-case for this:
  2644 //    - calling get_thread_pc() on the VMThread by the flat-profiler task
  2645 //      that runs in the watcher thread.
  2646 //  The remaining code is greatly simplified from the more general suspension
  2647 //  code that used to be used.
  2648 //
  2649 //  The protocol is quite simple:
  2650 //  - suspend:
  2651 //      - sends a signal to the target thread
  2652 //      - polls the suspend state of the osthread using a yield loop
  2653 //      - target thread signal handler (SR_handler) sets suspend state
  2654 //        and blocks in sigsuspend until continued
  2655 //  - resume:
  2656 //      - sets target osthread state to continue
  2657 //      - sends signal to end the sigsuspend loop in the SR_handler
  2658 //
  2659 //  Note that the SR_lock plays no role in this suspend/resume protocol.
  2660 //
  2662 static void resume_clear_context(OSThread *osthread) {
  2663   osthread->set_ucontext(NULL);
  2664   osthread->set_siginfo(NULL);
  2666   // notify the suspend action is completed, we have now resumed
  2667   osthread->sr.clear_suspended();
  2670 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
  2671   osthread->set_ucontext(context);
  2672   osthread->set_siginfo(siginfo);
  2675 //
  2676 // Handler function invoked when a thread's execution is suspended or
  2677 // resumed. We have to be careful that only async-safe functions are
  2678 // called here (Note: most pthread functions are not async safe and
  2679 // should be avoided.)
  2680 //
  2681 // Note: sigwait() is a more natural fit than sigsuspend() from an
  2682 // interface point of view, but sigwait() prevents the signal hander
  2683 // from being run. libpthread would get very confused by not having
  2684 // its signal handlers run and prevents sigwait()'s use with the
  2685 // mutex granting granting signal.
  2686 //
  2687 // Currently only ever called on the VMThread
  2688 //
  2689 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
  2690   // Save and restore errno to avoid confusing native code with EINTR
  2691   // after sigsuspend.
  2692   int old_errno = errno;
  2694   Thread* thread = Thread::current();
  2695   OSThread* osthread = thread->osthread();
  2696   assert(thread->is_VM_thread(), "Must be VMThread");
  2697   // read current suspend action
  2698   int action = osthread->sr.suspend_action();
  2699   if (action == os::Bsd::SuspendResume::SR_SUSPEND) {
  2700     suspend_save_context(osthread, siginfo, context);
  2702     // Notify the suspend action is about to be completed. do_suspend()
  2703     // waits until SR_SUSPENDED is set and then returns. We will wait
  2704     // here for a resume signal and that completes the suspend-other
  2705     // action. do_suspend/do_resume is always called as a pair from
  2706     // the same thread - so there are no races
  2708     // notify the caller
  2709     osthread->sr.set_suspended();
  2711     sigset_t suspend_set;  // signals for sigsuspend()
  2713     // get current set of blocked signals and unblock resume signal
  2714     pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
  2715     sigdelset(&suspend_set, SR_signum);
  2717     // wait here until we are resumed
  2718     do {
  2719       sigsuspend(&suspend_set);
  2720       // ignore all returns until we get a resume signal
  2721     } while (osthread->sr.suspend_action() != os::Bsd::SuspendResume::SR_CONTINUE);
  2723     resume_clear_context(osthread);
  2725   } else {
  2726     assert(action == os::Bsd::SuspendResume::SR_CONTINUE, "unexpected sr action");
  2727     // nothing special to do - just leave the handler
  2730   errno = old_errno;
  2734 static int SR_initialize() {
  2735   struct sigaction act;
  2736   char *s;
  2737   /* Get signal number to use for suspend/resume */
  2738   if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
  2739     int sig = ::strtol(s, 0, 10);
  2740     if (sig > 0 || sig < NSIG) {
  2741         SR_signum = sig;
  2745   assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
  2746         "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
  2748   sigemptyset(&SR_sigset);
  2749   sigaddset(&SR_sigset, SR_signum);
  2751   /* Set up signal handler for suspend/resume */
  2752   act.sa_flags = SA_RESTART|SA_SIGINFO;
  2753   act.sa_handler = (void (*)(int)) SR_handler;
  2755   // SR_signum is blocked by default.
  2756   // 4528190 - We also need to block pthread restart signal (32 on all
  2757   // supported Bsd platforms). Note that BsdThreads need to block
  2758   // this signal for all threads to work properly. So we don't have
  2759   // to use hard-coded signal number when setting up the mask.
  2760   pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
  2762   if (sigaction(SR_signum, &act, 0) == -1) {
  2763     return -1;
  2766   // Save signal flag
  2767   os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
  2768   return 0;
  2772 // returns true on success and false on error - really an error is fatal
  2773 // but this seems the normal response to library errors
  2774 static bool do_suspend(OSThread* osthread) {
  2775   // mark as suspended and send signal
  2776   osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_SUSPEND);
  2777   int status = pthread_kill(osthread->pthread_id(), SR_signum);
  2778   assert_status(status == 0, status, "pthread_kill");
  2780   // check status and wait until notified of suspension
  2781   if (status == 0) {
  2782     for (int i = 0; !osthread->sr.is_suspended(); i++) {
  2783       os::yield_all(i);
  2785     osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
  2786     return true;
  2788   else {
  2789     osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
  2790     return false;
  2794 static void do_resume(OSThread* osthread) {
  2795   assert(osthread->sr.is_suspended(), "thread should be suspended");
  2796   osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_CONTINUE);
  2798   int status = pthread_kill(osthread->pthread_id(), SR_signum);
  2799   assert_status(status == 0, status, "pthread_kill");
  2800   // check status and wait unit notified of resumption
  2801   if (status == 0) {
  2802     for (int i = 0; osthread->sr.is_suspended(); i++) {
  2803       os::yield_all(i);
  2806   osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
  2809 ////////////////////////////////////////////////////////////////////////////////
  2810 // interrupt support
  2812 void os::interrupt(Thread* thread) {
  2813   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  2814     "possibility of dangling Thread pointer");
  2816   OSThread* osthread = thread->osthread();
  2818   if (!osthread->interrupted()) {
  2819     osthread->set_interrupted(true);
  2820     // More than one thread can get here with the same value of osthread,
  2821     // resulting in multiple notifications.  We do, however, want the store
  2822     // to interrupted() to be visible to other threads before we execute unpark().
  2823     OrderAccess::fence();
  2824     ParkEvent * const slp = thread->_SleepEvent ;
  2825     if (slp != NULL) slp->unpark() ;
  2828   // For JSR166. Unpark even if interrupt status already was set
  2829   if (thread->is_Java_thread())
  2830     ((JavaThread*)thread)->parker()->unpark();
  2832   ParkEvent * ev = thread->_ParkEvent ;
  2833   if (ev != NULL) ev->unpark() ;
  2837 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
  2838   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  2839     "possibility of dangling Thread pointer");
  2841   OSThread* osthread = thread->osthread();
  2843   bool interrupted = osthread->interrupted();
  2845   if (interrupted && clear_interrupted) {
  2846     osthread->set_interrupted(false);
  2847     // consider thread->_SleepEvent->reset() ... optional optimization
  2850   return interrupted;
  2853 ///////////////////////////////////////////////////////////////////////////////////
  2854 // signal handling (except suspend/resume)
  2856 // This routine may be used by user applications as a "hook" to catch signals.
  2857 // The user-defined signal handler must pass unrecognized signals to this
  2858 // routine, and if it returns true (non-zero), then the signal handler must
  2859 // return immediately.  If the flag "abort_if_unrecognized" is true, then this
  2860 // routine will never retun false (zero), but instead will execute a VM panic
  2861 // routine kill the process.
  2862 //
  2863 // If this routine returns false, it is OK to call it again.  This allows
  2864 // the user-defined signal handler to perform checks either before or after
  2865 // the VM performs its own checks.  Naturally, the user code would be making
  2866 // a serious error if it tried to handle an exception (such as a null check
  2867 // or breakpoint) that the VM was generating for its own correct operation.
  2868 //
  2869 // This routine may recognize any of the following kinds of signals:
  2870 //    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
  2871 // It should be consulted by handlers for any of those signals.
  2872 //
  2873 // The caller of this routine must pass in the three arguments supplied
  2874 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
  2875 // field of the structure passed to sigaction().  This routine assumes that
  2876 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
  2877 //
  2878 // Note that the VM will print warnings if it detects conflicting signal
  2879 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
  2880 //
  2881 extern "C" JNIEXPORT int
  2882 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
  2883                         void* ucontext, int abort_if_unrecognized);
  2885 void signalHandler(int sig, siginfo_t* info, void* uc) {
  2886   assert(info != NULL && uc != NULL, "it must be old kernel");
  2887   int orig_errno = errno;  // Preserve errno value over signal handler.
  2888   JVM_handle_bsd_signal(sig, info, uc, true);
  2889   errno = orig_errno;
  2893 // This boolean allows users to forward their own non-matching signals
  2894 // to JVM_handle_bsd_signal, harmlessly.
  2895 bool os::Bsd::signal_handlers_are_installed = false;
  2897 // For signal-chaining
  2898 struct sigaction os::Bsd::sigact[MAXSIGNUM];
  2899 unsigned int os::Bsd::sigs = 0;
  2900 bool os::Bsd::libjsig_is_loaded = false;
  2901 typedef struct sigaction *(*get_signal_t)(int);
  2902 get_signal_t os::Bsd::get_signal_action = NULL;
  2904 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
  2905   struct sigaction *actp = NULL;
  2907   if (libjsig_is_loaded) {
  2908     // Retrieve the old signal handler from libjsig
  2909     actp = (*get_signal_action)(sig);
  2911   if (actp == NULL) {
  2912     // Retrieve the preinstalled signal handler from jvm
  2913     actp = get_preinstalled_handler(sig);
  2916   return actp;
  2919 static bool call_chained_handler(struct sigaction *actp, int sig,
  2920                                  siginfo_t *siginfo, void *context) {
  2921   // Call the old signal handler
  2922   if (actp->sa_handler == SIG_DFL) {
  2923     // It's more reasonable to let jvm treat it as an unexpected exception
  2924     // instead of taking the default action.
  2925     return false;
  2926   } else if (actp->sa_handler != SIG_IGN) {
  2927     if ((actp->sa_flags & SA_NODEFER) == 0) {
  2928       // automaticlly block the signal
  2929       sigaddset(&(actp->sa_mask), sig);
  2932     sa_handler_t hand;
  2933     sa_sigaction_t sa;
  2934     bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
  2935     // retrieve the chained handler
  2936     if (siginfo_flag_set) {
  2937       sa = actp->sa_sigaction;
  2938     } else {
  2939       hand = actp->sa_handler;
  2942     if ((actp->sa_flags & SA_RESETHAND) != 0) {
  2943       actp->sa_handler = SIG_DFL;
  2946     // try to honor the signal mask
  2947     sigset_t oset;
  2948     pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
  2950     // call into the chained handler
  2951     if (siginfo_flag_set) {
  2952       (*sa)(sig, siginfo, context);
  2953     } else {
  2954       (*hand)(sig);
  2957     // restore the signal mask
  2958     pthread_sigmask(SIG_SETMASK, &oset, 0);
  2960   // Tell jvm's signal handler the signal is taken care of.
  2961   return true;
  2964 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
  2965   bool chained = false;
  2966   // signal-chaining
  2967   if (UseSignalChaining) {
  2968     struct sigaction *actp = get_chained_signal_action(sig);
  2969     if (actp != NULL) {
  2970       chained = call_chained_handler(actp, sig, siginfo, context);
  2973   return chained;
  2976 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
  2977   if ((( (unsigned int)1 << sig ) & sigs) != 0) {
  2978     return &sigact[sig];
  2980   return NULL;
  2983 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
  2984   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  2985   sigact[sig] = oldAct;
  2986   sigs |= (unsigned int)1 << sig;
  2989 // for diagnostic
  2990 int os::Bsd::sigflags[MAXSIGNUM];
  2992 int os::Bsd::get_our_sigflags(int sig) {
  2993   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  2994   return sigflags[sig];
  2997 void os::Bsd::set_our_sigflags(int sig, int flags) {
  2998   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  2999   sigflags[sig] = flags;
  3002 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
  3003   // Check for overwrite.
  3004   struct sigaction oldAct;
  3005   sigaction(sig, (struct sigaction*)NULL, &oldAct);
  3007   void* oldhand = oldAct.sa_sigaction
  3008                 ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
  3009                 : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
  3010   if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
  3011       oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
  3012       oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
  3013     if (AllowUserSignalHandlers || !set_installed) {
  3014       // Do not overwrite; user takes responsibility to forward to us.
  3015       return;
  3016     } else if (UseSignalChaining) {
  3017       // save the old handler in jvm
  3018       save_preinstalled_handler(sig, oldAct);
  3019       // libjsig also interposes the sigaction() call below and saves the
  3020       // old sigaction on it own.
  3021     } else {
  3022       fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
  3023                     "%#lx for signal %d.", (long)oldhand, sig));
  3027   struct sigaction sigAct;
  3028   sigfillset(&(sigAct.sa_mask));
  3029   sigAct.sa_handler = SIG_DFL;
  3030   if (!set_installed) {
  3031     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3032   } else {
  3033     sigAct.sa_sigaction = signalHandler;
  3034     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3036   // Save flags, which are set by ours
  3037   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3038   sigflags[sig] = sigAct.sa_flags;
  3040   int ret = sigaction(sig, &sigAct, &oldAct);
  3041   assert(ret == 0, "check");
  3043   void* oldhand2  = oldAct.sa_sigaction
  3044                   ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
  3045                   : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
  3046   assert(oldhand2 == oldhand, "no concurrent signal handler installation");
  3049 // install signal handlers for signals that HotSpot needs to
  3050 // handle in order to support Java-level exception handling.
  3052 void os::Bsd::install_signal_handlers() {
  3053   if (!signal_handlers_are_installed) {
  3054     signal_handlers_are_installed = true;
  3056     // signal-chaining
  3057     typedef void (*signal_setting_t)();
  3058     signal_setting_t begin_signal_setting = NULL;
  3059     signal_setting_t end_signal_setting = NULL;
  3060     begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3061                              dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
  3062     if (begin_signal_setting != NULL) {
  3063       end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3064                              dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
  3065       get_signal_action = CAST_TO_FN_PTR(get_signal_t,
  3066                             dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
  3067       libjsig_is_loaded = true;
  3068       assert(UseSignalChaining, "should enable signal-chaining");
  3070     if (libjsig_is_loaded) {
  3071       // Tell libjsig jvm is setting signal handlers
  3072       (*begin_signal_setting)();
  3075     set_signal_handler(SIGSEGV, true);
  3076     set_signal_handler(SIGPIPE, true);
  3077     set_signal_handler(SIGBUS, true);
  3078     set_signal_handler(SIGILL, true);
  3079     set_signal_handler(SIGFPE, true);
  3080     set_signal_handler(SIGXFSZ, true);
  3082 #if defined(__APPLE__)
  3083     // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
  3084     // signals caught and handled by the JVM. To work around this, we reset the mach task
  3085     // signal handler that's placed on our process by CrashReporter. This disables
  3086     // CrashReporter-based reporting.
  3087     //
  3088     // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
  3089     // on caught fatal signals.
  3090     //
  3091     // Additionally, gdb installs both standard BSD signal handlers, and mach exception
  3092     // handlers. By replacing the existing task exception handler, we disable gdb's mach
  3093     // exception handling, while leaving the standard BSD signal handlers functional.
  3094     kern_return_t kr;
  3095     kr = task_set_exception_ports(mach_task_self(),
  3096         EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
  3097         MACH_PORT_NULL,
  3098         EXCEPTION_STATE_IDENTITY,
  3099         MACHINE_THREAD_STATE);
  3101     assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
  3102 #endif
  3104     if (libjsig_is_loaded) {
  3105       // Tell libjsig jvm finishes setting signal handlers
  3106       (*end_signal_setting)();
  3109     // We don't activate signal checker if libjsig is in place, we trust ourselves
  3110     // and if UserSignalHandler is installed all bets are off
  3111     if (CheckJNICalls) {
  3112       if (libjsig_is_loaded) {
  3113         tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
  3114         check_signals = false;
  3116       if (AllowUserSignalHandlers) {
  3117         tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
  3118         check_signals = false;
  3125 /////
  3126 // glibc on Bsd platform uses non-documented flag
  3127 // to indicate, that some special sort of signal
  3128 // trampoline is used.
  3129 // We will never set this flag, and we should
  3130 // ignore this flag in our diagnostic
  3131 #ifdef SIGNIFICANT_SIGNAL_MASK
  3132 #undef SIGNIFICANT_SIGNAL_MASK
  3133 #endif
  3134 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
  3136 static const char* get_signal_handler_name(address handler,
  3137                                            char* buf, int buflen) {
  3138   int offset;
  3139   bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
  3140   if (found) {
  3141     // skip directory names
  3142     const char *p1, *p2;
  3143     p1 = buf;
  3144     size_t len = strlen(os::file_separator());
  3145     while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
  3146     jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
  3147   } else {
  3148     jio_snprintf(buf, buflen, PTR_FORMAT, handler);
  3150   return buf;
  3153 static void print_signal_handler(outputStream* st, int sig,
  3154                                  char* buf, size_t buflen) {
  3155   struct sigaction sa;
  3157   sigaction(sig, NULL, &sa);
  3159   // See comment for SIGNIFICANT_SIGNAL_MASK define
  3160   sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3162   st->print("%s: ", os::exception_name(sig, buf, buflen));
  3164   address handler = (sa.sa_flags & SA_SIGINFO)
  3165     ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
  3166     : CAST_FROM_FN_PTR(address, sa.sa_handler);
  3168   if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
  3169     st->print("SIG_DFL");
  3170   } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
  3171     st->print("SIG_IGN");
  3172   } else {
  3173     st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
  3176   st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
  3178   address rh = VMError::get_resetted_sighandler(sig);
  3179   // May be, handler was resetted by VMError?
  3180   if(rh != NULL) {
  3181     handler = rh;
  3182     sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
  3185   st->print(", sa_flags="   PTR32_FORMAT, sa.sa_flags);
  3187   // Check: is it our handler?
  3188   if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
  3189      handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
  3190     // It is our signal handler
  3191     // check for flags, reset system-used one!
  3192     if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3193       st->print(
  3194                 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
  3195                 os::Bsd::get_our_sigflags(sig));
  3198   st->cr();
  3202 #define DO_SIGNAL_CHECK(sig) \
  3203   if (!sigismember(&check_signal_done, sig)) \
  3204     os::Bsd::check_signal_handler(sig)
  3206 // This method is a periodic task to check for misbehaving JNI applications
  3207 // under CheckJNI, we can add any periodic checks here
  3209 void os::run_periodic_checks() {
  3211   if (check_signals == false) return;
  3213   // SEGV and BUS if overridden could potentially prevent
  3214   // generation of hs*.log in the event of a crash, debugging
  3215   // such a case can be very challenging, so we absolutely
  3216   // check the following for a good measure:
  3217   DO_SIGNAL_CHECK(SIGSEGV);
  3218   DO_SIGNAL_CHECK(SIGILL);
  3219   DO_SIGNAL_CHECK(SIGFPE);
  3220   DO_SIGNAL_CHECK(SIGBUS);
  3221   DO_SIGNAL_CHECK(SIGPIPE);
  3222   DO_SIGNAL_CHECK(SIGXFSZ);
  3225   // ReduceSignalUsage allows the user to override these handlers
  3226   // see comments at the very top and jvm_solaris.h
  3227   if (!ReduceSignalUsage) {
  3228     DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
  3229     DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
  3230     DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
  3231     DO_SIGNAL_CHECK(BREAK_SIGNAL);
  3234   DO_SIGNAL_CHECK(SR_signum);
  3235   DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
  3238 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
  3240 static os_sigaction_t os_sigaction = NULL;
  3242 void os::Bsd::check_signal_handler(int sig) {
  3243   char buf[O_BUFLEN];
  3244   address jvmHandler = NULL;
  3247   struct sigaction act;
  3248   if (os_sigaction == NULL) {
  3249     // only trust the default sigaction, in case it has been interposed
  3250     os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
  3251     if (os_sigaction == NULL) return;
  3254   os_sigaction(sig, (struct sigaction*)NULL, &act);
  3257   act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3259   address thisHandler = (act.sa_flags & SA_SIGINFO)
  3260     ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
  3261     : CAST_FROM_FN_PTR(address, act.sa_handler) ;
  3264   switch(sig) {
  3265   case SIGSEGV:
  3266   case SIGBUS:
  3267   case SIGFPE:
  3268   case SIGPIPE:
  3269   case SIGILL:
  3270   case SIGXFSZ:
  3271     jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
  3272     break;
  3274   case SHUTDOWN1_SIGNAL:
  3275   case SHUTDOWN2_SIGNAL:
  3276   case SHUTDOWN3_SIGNAL:
  3277   case BREAK_SIGNAL:
  3278     jvmHandler = (address)user_handler();
  3279     break;
  3281   case INTERRUPT_SIGNAL:
  3282     jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
  3283     break;
  3285   default:
  3286     if (sig == SR_signum) {
  3287       jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
  3288     } else {
  3289       return;
  3291     break;
  3294   if (thisHandler != jvmHandler) {
  3295     tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
  3296     tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
  3297     tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
  3298     // No need to check this sig any longer
  3299     sigaddset(&check_signal_done, sig);
  3300   } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3301     tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
  3302     tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
  3303     tty->print_cr("  found:" PTR32_FORMAT, act.sa_flags);
  3304     // No need to check this sig any longer
  3305     sigaddset(&check_signal_done, sig);
  3308   // Dump all the signal
  3309   if (sigismember(&check_signal_done, sig)) {
  3310     print_signal_handlers(tty, buf, O_BUFLEN);
  3314 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
  3316 extern bool signal_name(int signo, char* buf, size_t len);
  3318 const char* os::exception_name(int exception_code, char* buf, size_t size) {
  3319   if (0 < exception_code && exception_code <= SIGRTMAX) {
  3320     // signal
  3321     if (!signal_name(exception_code, buf, size)) {
  3322       jio_snprintf(buf, size, "SIG%d", exception_code);
  3324     return buf;
  3325   } else {
  3326     return NULL;
  3330 // this is called _before_ the most of global arguments have been parsed
  3331 void os::init(void) {
  3332   char dummy;   /* used to get a guess on initial stack address */
  3333 //  first_hrtime = gethrtime();
  3335   // With BsdThreads the JavaMain thread pid (primordial thread)
  3336   // is different than the pid of the java launcher thread.
  3337   // So, on Bsd, the launcher thread pid is passed to the VM
  3338   // via the sun.java.launcher.pid property.
  3339   // Use this property instead of getpid() if it was correctly passed.
  3340   // See bug 6351349.
  3341   pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
  3343   _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
  3345   clock_tics_per_sec = CLK_TCK;
  3347   init_random(1234567);
  3349   ThreadCritical::initialize();
  3351   Bsd::set_page_size(getpagesize());
  3352   if (Bsd::page_size() == -1) {
  3353     fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
  3354                   strerror(errno)));
  3356   init_page_sizes((size_t) Bsd::page_size());
  3358   Bsd::initialize_system_info();
  3360   // main_thread points to the aboriginal thread
  3361   Bsd::_main_thread = pthread_self();
  3363   Bsd::clock_init();
  3364   initial_time_count = os::elapsed_counter();
  3366 #ifdef __APPLE__
  3367   // XXXDARWIN
  3368   // Work around the unaligned VM callbacks in hotspot's
  3369   // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
  3370   // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
  3371   // alignment when doing symbol lookup. To work around this, we force early
  3372   // binding of all symbols now, thus binding when alignment is known-good.
  3373   _dyld_bind_fully_image_containing_address((const void *) &os::init);
  3374 #endif
  3377 // To install functions for atexit system call
  3378 extern "C" {
  3379   static void perfMemory_exit_helper() {
  3380     perfMemory_exit();
  3384 // this is called _after_ the global arguments have been parsed
  3385 jint os::init_2(void)
  3387   // Allocate a single page and mark it as readable for safepoint polling
  3388   address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3389   guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
  3391   os::set_polling_page( polling_page );
  3393 #ifndef PRODUCT
  3394   if(Verbose && PrintMiscellaneous)
  3395     tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
  3396 #endif
  3398   if (!UseMembar) {
  3399     address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3400     guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
  3401     os::set_memory_serialize_page( mem_serialize_page );
  3403 #ifndef PRODUCT
  3404     if(Verbose && PrintMiscellaneous)
  3405       tty->print("[Memory Serialize  Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
  3406 #endif
  3409   os::large_page_init();
  3411   // initialize suspend/resume support - must do this before signal_sets_init()
  3412   if (SR_initialize() != 0) {
  3413     perror("SR_initialize failed");
  3414     return JNI_ERR;
  3417   Bsd::signal_sets_init();
  3418   Bsd::install_signal_handlers();
  3420   // Check minimum allowable stack size for thread creation and to initialize
  3421   // the java system classes, including StackOverflowError - depends on page
  3422   // size.  Add a page for compiler2 recursion in main thread.
  3423   // Add in 2*BytesPerWord times page size to account for VM stack during
  3424   // class initialization depending on 32 or 64 bit VM.
  3425   os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
  3426             (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
  3427                     2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
  3429   size_t threadStackSizeInBytes = ThreadStackSize * K;
  3430   if (threadStackSizeInBytes != 0 &&
  3431       threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
  3432         tty->print_cr("\nThe stack size specified is too small, "
  3433                       "Specify at least %dk",
  3434                       os::Bsd::min_stack_allowed/ K);
  3435         return JNI_ERR;
  3438   // Make the stack size a multiple of the page size so that
  3439   // the yellow/red zones can be guarded.
  3440   JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
  3441         vm_page_size()));
  3443   if (MaxFDLimit) {
  3444     // set the number of file descriptors to max. print out error
  3445     // if getrlimit/setrlimit fails but continue regardless.
  3446     struct rlimit nbr_files;
  3447     int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
  3448     if (status != 0) {
  3449       if (PrintMiscellaneous && (Verbose || WizardMode))
  3450         perror("os::init_2 getrlimit failed");
  3451     } else {
  3452       nbr_files.rlim_cur = nbr_files.rlim_max;
  3454 #ifdef __APPLE__
  3455       // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
  3456       // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
  3457       // be used instead
  3458       nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
  3459 #endif
  3461       status = setrlimit(RLIMIT_NOFILE, &nbr_files);
  3462       if (status != 0) {
  3463         if (PrintMiscellaneous && (Verbose || WizardMode))
  3464           perror("os::init_2 setrlimit failed");
  3469   // at-exit methods are called in the reverse order of their registration.
  3470   // atexit functions are called on return from main or as a result of a
  3471   // call to exit(3C). There can be only 32 of these functions registered
  3472   // and atexit() does not set errno.
  3474   if (PerfAllowAtExitRegistration) {
  3475     // only register atexit functions if PerfAllowAtExitRegistration is set.
  3476     // atexit functions can be delayed until process exit time, which
  3477     // can be problematic for embedded VM situations. Embedded VMs should
  3478     // call DestroyJavaVM() to assure that VM resources are released.
  3480     // note: perfMemory_exit_helper atexit function may be removed in
  3481     // the future if the appropriate cleanup code can be added to the
  3482     // VM_Exit VMOperation's doit method.
  3483     if (atexit(perfMemory_exit_helper) != 0) {
  3484       warning("os::init2 atexit(perfMemory_exit_helper) failed");
  3488   // initialize thread priority policy
  3489   prio_init();
  3491 #ifdef __APPLE__
  3492   // dynamically link to objective c gc registration
  3493   void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
  3494   if (handleLibObjc != NULL) {
  3495     objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
  3497 #endif
  3499   return JNI_OK;
  3502 // this is called at the end of vm_initialization
  3503 void os::init_3(void) { }
  3505 // Mark the polling page as unreadable
  3506 void os::make_polling_page_unreadable(void) {
  3507   if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
  3508     fatal("Could not disable polling page");
  3509 };
  3511 // Mark the polling page as readable
  3512 void os::make_polling_page_readable(void) {
  3513   if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
  3514     fatal("Could not enable polling page");
  3516 };
  3518 int os::active_processor_count() {
  3519   return _processor_count;
  3522 void os::set_native_thread_name(const char *name) {
  3523 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
  3524   // This is only supported in Snow Leopard and beyond
  3525   if (name != NULL) {
  3526     // Add a "Java: " prefix to the name
  3527     char buf[MAXTHREADNAMESIZE];
  3528     snprintf(buf, sizeof(buf), "Java: %s", name);
  3529     pthread_setname_np(buf);
  3531 #endif
  3534 bool os::distribute_processes(uint length, uint* distribution) {
  3535   // Not yet implemented.
  3536   return false;
  3539 bool os::bind_to_processor(uint processor_id) {
  3540   // Not yet implemented.
  3541   return false;
  3544 ///
  3546 // Suspends the target using the signal mechanism and then grabs the PC before
  3547 // resuming the target. Used by the flat-profiler only
  3548 ExtendedPC os::get_thread_pc(Thread* thread) {
  3549   // Make sure that it is called by the watcher for the VMThread
  3550   assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
  3551   assert(thread->is_VM_thread(), "Can only be called for VMThread");
  3553   ExtendedPC epc;
  3555   OSThread* osthread = thread->osthread();
  3556   if (do_suspend(osthread)) {
  3557     if (osthread->ucontext() != NULL) {
  3558       epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
  3559     } else {
  3560       // NULL context is unexpected, double-check this is the VMThread
  3561       guarantee(thread->is_VM_thread(), "can only be called for VMThread");
  3563     do_resume(osthread);
  3565   // failure means pthread_kill failed for some reason - arguably this is
  3566   // a fatal problem, but such problems are ignored elsewhere
  3568   return epc;
  3571 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
  3573   return pthread_cond_timedwait(_cond, _mutex, _abstime);
  3576 ////////////////////////////////////////////////////////////////////////////////
  3577 // debug support
  3579 bool os::find(address addr, outputStream* st) {
  3580   Dl_info dlinfo;
  3581   memset(&dlinfo, 0, sizeof(dlinfo));
  3582   if (dladdr(addr, &dlinfo)) {
  3583     st->print(PTR_FORMAT ": ", addr);
  3584     if (dlinfo.dli_sname != NULL) {
  3585       st->print("%s+%#x", dlinfo.dli_sname,
  3586                  addr - (intptr_t)dlinfo.dli_saddr);
  3587     } else if (dlinfo.dli_fname) {
  3588       st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
  3589     } else {
  3590       st->print("<absolute address>");
  3592     if (dlinfo.dli_fname) {
  3593       st->print(" in %s", dlinfo.dli_fname);
  3595     if (dlinfo.dli_fbase) {
  3596       st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
  3598     st->cr();
  3600     if (Verbose) {
  3601       // decode some bytes around the PC
  3602       address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
  3603       address end   = clamp_address_in_page(addr+40, addr, os::vm_page_size());
  3604       address       lowest = (address) dlinfo.dli_sname;
  3605       if (!lowest)  lowest = (address) dlinfo.dli_fbase;
  3606       if (begin < lowest)  begin = lowest;
  3607       Dl_info dlinfo2;
  3608       if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
  3609           && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
  3610         end = (address) dlinfo2.dli_saddr;
  3611       Disassembler::decode(begin, end, st);
  3613     return true;
  3615   return false;
  3618 ////////////////////////////////////////////////////////////////////////////////
  3619 // misc
  3621 // This does not do anything on Bsd. This is basically a hook for being
  3622 // able to use structured exception handling (thread-local exception filters)
  3623 // on, e.g., Win32.
  3624 void
  3625 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
  3626                          JavaCallArguments* args, Thread* thread) {
  3627   f(value, method, args, thread);
  3630 void os::print_statistics() {
  3633 int os::message_box(const char* title, const char* message) {
  3634   int i;
  3635   fdStream err(defaultStream::error_fd());
  3636   for (i = 0; i < 78; i++) err.print_raw("=");
  3637   err.cr();
  3638   err.print_raw_cr(title);
  3639   for (i = 0; i < 78; i++) err.print_raw("-");
  3640   err.cr();
  3641   err.print_raw_cr(message);
  3642   for (i = 0; i < 78; i++) err.print_raw("=");
  3643   err.cr();
  3645   char buf[16];
  3646   // Prevent process from exiting upon "read error" without consuming all CPU
  3647   while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
  3649   return buf[0] == 'y' || buf[0] == 'Y';
  3652 int os::stat(const char *path, struct stat *sbuf) {
  3653   char pathbuf[MAX_PATH];
  3654   if (strlen(path) > MAX_PATH - 1) {
  3655     errno = ENAMETOOLONG;
  3656     return -1;
  3658   os::native_path(strcpy(pathbuf, path));
  3659   return ::stat(pathbuf, sbuf);
  3662 bool os::check_heap(bool force) {
  3663   return true;
  3666 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
  3667   return ::vsnprintf(buf, count, format, args);
  3670 // Is a (classpath) directory empty?
  3671 bool os::dir_is_empty(const char* path) {
  3672   DIR *dir = NULL;
  3673   struct dirent *ptr;
  3675   dir = opendir(path);
  3676   if (dir == NULL) return true;
  3678   /* Scan the directory */
  3679   bool result = true;
  3680   char buf[sizeof(struct dirent) + MAX_PATH];
  3681   while (result && (ptr = ::readdir(dir)) != NULL) {
  3682     if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
  3683       result = false;
  3686   closedir(dir);
  3687   return result;
  3690 // This code originates from JDK's sysOpen and open64_w
  3691 // from src/solaris/hpi/src/system_md.c
  3693 #ifndef O_DELETE
  3694 #define O_DELETE 0x10000
  3695 #endif
  3697 // Open a file. Unlink the file immediately after open returns
  3698 // if the specified oflag has the O_DELETE flag set.
  3699 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
  3701 int os::open(const char *path, int oflag, int mode) {
  3703   if (strlen(path) > MAX_PATH - 1) {
  3704     errno = ENAMETOOLONG;
  3705     return -1;
  3707   int fd;
  3708   int o_delete = (oflag & O_DELETE);
  3709   oflag = oflag & ~O_DELETE;
  3711   fd = ::open(path, oflag, mode);
  3712   if (fd == -1) return -1;
  3714   //If the open succeeded, the file might still be a directory
  3716     struct stat buf;
  3717     int ret = ::fstat(fd, &buf);
  3718     int st_mode = buf.st_mode;
  3720     if (ret != -1) {
  3721       if ((st_mode & S_IFMT) == S_IFDIR) {
  3722         errno = EISDIR;
  3723         ::close(fd);
  3724         return -1;
  3726     } else {
  3727       ::close(fd);
  3728       return -1;
  3732     /*
  3733      * All file descriptors that are opened in the JVM and not
  3734      * specifically destined for a subprocess should have the
  3735      * close-on-exec flag set.  If we don't set it, then careless 3rd
  3736      * party native code might fork and exec without closing all
  3737      * appropriate file descriptors (e.g. as we do in closeDescriptors in
  3738      * UNIXProcess.c), and this in turn might:
  3740      * - cause end-of-file to fail to be detected on some file
  3741      *   descriptors, resulting in mysterious hangs, or
  3743      * - might cause an fopen in the subprocess to fail on a system
  3744      *   suffering from bug 1085341.
  3746      * (Yes, the default setting of the close-on-exec flag is a Unix
  3747      * design flaw)
  3749      * See:
  3750      * 1085341: 32-bit stdio routines should support file descriptors >255
  3751      * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
  3752      * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
  3753      */
  3754 #ifdef FD_CLOEXEC
  3756         int flags = ::fcntl(fd, F_GETFD);
  3757         if (flags != -1)
  3758             ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
  3760 #endif
  3762   if (o_delete != 0) {
  3763     ::unlink(path);
  3765   return fd;
  3769 // create binary file, rewriting existing file if required
  3770 int os::create_binary_file(const char* path, bool rewrite_existing) {
  3771   int oflags = O_WRONLY | O_CREAT;
  3772   if (!rewrite_existing) {
  3773     oflags |= O_EXCL;
  3775   return ::open(path, oflags, S_IREAD | S_IWRITE);
  3778 // return current position of file pointer
  3779 jlong os::current_file_offset(int fd) {
  3780   return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
  3783 // move file pointer to the specified offset
  3784 jlong os::seek_to_file_offset(int fd, jlong offset) {
  3785   return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
  3788 // This code originates from JDK's sysAvailable
  3789 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
  3791 int os::available(int fd, jlong *bytes) {
  3792   jlong cur, end;
  3793   int mode;
  3794   struct stat buf;
  3796   if (::fstat(fd, &buf) >= 0) {
  3797     mode = buf.st_mode;
  3798     if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
  3799       /*
  3800       * XXX: is the following call interruptible? If so, this might
  3801       * need to go through the INTERRUPT_IO() wrapper as for other
  3802       * blocking, interruptible calls in this file.
  3803       */
  3804       int n;
  3805       if (::ioctl(fd, FIONREAD, &n) >= 0) {
  3806         *bytes = n;
  3807         return 1;
  3811   if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
  3812     return 0;
  3813   } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
  3814     return 0;
  3815   } else if (::lseek(fd, cur, SEEK_SET) == -1) {
  3816     return 0;
  3818   *bytes = end - cur;
  3819   return 1;
  3822 int os::socket_available(int fd, jint *pbytes) {
  3823    if (fd < 0)
  3824      return OS_OK;
  3826    int ret;
  3828    RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
  3830    //%% note ioctl can return 0 when successful, JVM_SocketAvailable
  3831    // is expected to return 0 on failure and 1 on success to the jdk.
  3833    return (ret == OS_ERR) ? 0 : 1;
  3836 // Map a block of memory.
  3837 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
  3838                      char *addr, size_t bytes, bool read_only,
  3839                      bool allow_exec) {
  3840   int prot;
  3841   int flags;
  3843   if (read_only) {
  3844     prot = PROT_READ;
  3845     flags = MAP_SHARED;
  3846   } else {
  3847     prot = PROT_READ | PROT_WRITE;
  3848     flags = MAP_PRIVATE;
  3851   if (allow_exec) {
  3852     prot |= PROT_EXEC;
  3855   if (addr != NULL) {
  3856     flags |= MAP_FIXED;
  3859   char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
  3860                                      fd, file_offset);
  3861   if (mapped_address == MAP_FAILED) {
  3862     return NULL;
  3864   return mapped_address;
  3868 // Remap a block of memory.
  3869 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
  3870                        char *addr, size_t bytes, bool read_only,
  3871                        bool allow_exec) {
  3872   // same as map_memory() on this OS
  3873   return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
  3874                         allow_exec);
  3878 // Unmap a block of memory.
  3879 bool os::pd_unmap_memory(char* addr, size_t bytes) {
  3880   return munmap(addr, bytes) == 0;
  3883 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
  3884 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
  3885 // of a thread.
  3886 //
  3887 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
  3888 // the fast estimate available on the platform.
  3890 jlong os::current_thread_cpu_time() {
  3891 #ifdef __APPLE__
  3892   return os::thread_cpu_time(Thread::current(), true /* user + sys */);
  3893 #else
  3894   Unimplemented();
  3895   return 0;
  3896 #endif
  3899 jlong os::thread_cpu_time(Thread* thread) {
  3900 #ifdef __APPLE__
  3901   return os::thread_cpu_time(thread, true /* user + sys */);
  3902 #else
  3903   Unimplemented();
  3904   return 0;
  3905 #endif
  3908 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
  3909 #ifdef __APPLE__
  3910   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
  3911 #else
  3912   Unimplemented();
  3913   return 0;
  3914 #endif
  3917 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
  3918 #ifdef __APPLE__
  3919   struct thread_basic_info tinfo;
  3920   mach_msg_type_number_t tcount = THREAD_INFO_MAX;
  3921   kern_return_t kr;
  3922   thread_t mach_thread;
  3924   mach_thread = thread->osthread()->thread_id();
  3925   kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
  3926   if (kr != KERN_SUCCESS)
  3927     return -1;
  3929   if (user_sys_cpu_time) {
  3930     jlong nanos;
  3931     nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
  3932     nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
  3933     return nanos;
  3934   } else {
  3935     return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
  3937 #else
  3938   Unimplemented();
  3939   return 0;
  3940 #endif
  3944 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  3945   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  3946   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  3947   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  3948   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  3951 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  3952   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  3953   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  3954   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  3955   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  3958 bool os::is_thread_cpu_time_supported() {
  3959 #ifdef __APPLE__
  3960   return true;
  3961 #else
  3962   return false;
  3963 #endif
  3966 // System loadavg support.  Returns -1 if load average cannot be obtained.
  3967 // Bsd doesn't yet have a (official) notion of processor sets,
  3968 // so just return the system wide load average.
  3969 int os::loadavg(double loadavg[], int nelem) {
  3970   return ::getloadavg(loadavg, nelem);
  3973 void os::pause() {
  3974   char filename[MAX_PATH];
  3975   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
  3976     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
  3977   } else {
  3978     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
  3981   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
  3982   if (fd != -1) {
  3983     struct stat buf;
  3984     ::close(fd);
  3985     while (::stat(filename, &buf) == 0) {
  3986       (void)::poll(NULL, 0, 100);
  3988   } else {
  3989     jio_fprintf(stderr,
  3990       "Could not open pause file '%s', continuing immediately.\n", filename);
  3995 // Refer to the comments in os_solaris.cpp park-unpark.
  3996 //
  3997 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
  3998 // hang indefinitely.  For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
  3999 // For specifics regarding the bug see GLIBC BUGID 261237 :
  4000 //    http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
  4001 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
  4002 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
  4003 // is used.  (The simple C test-case provided in the GLIBC bug report manifests the
  4004 // hang).  The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
  4005 // and monitorenter when we're using 1-0 locking.  All those operations may result in
  4006 // calls to pthread_cond_timedwait().  Using LD_ASSUME_KERNEL to use an older version
  4007 // of libpthread avoids the problem, but isn't practical.
  4008 //
  4009 // Possible remedies:
  4010 //
  4011 // 1.   Establish a minimum relative wait time.  50 to 100 msecs seems to work.
  4012 //      This is palliative and probabilistic, however.  If the thread is preempted
  4013 //      between the call to compute_abstime() and pthread_cond_timedwait(), more
  4014 //      than the minimum period may have passed, and the abstime may be stale (in the
  4015 //      past) resultin in a hang.   Using this technique reduces the odds of a hang
  4016 //      but the JVM is still vulnerable, particularly on heavily loaded systems.
  4017 //
  4018 // 2.   Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
  4019 //      of the usual flag-condvar-mutex idiom.  The write side of the pipe is set
  4020 //      NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
  4021 //      reduces to poll()+read().  This works well, but consumes 2 FDs per extant
  4022 //      thread.
  4023 //
  4024 // 3.   Embargo pthread_cond_timedwait() and implement a native "chron" thread
  4025 //      that manages timeouts.  We'd emulate pthread_cond_timedwait() by enqueuing
  4026 //      a timeout request to the chron thread and then blocking via pthread_cond_wait().
  4027 //      This also works well.  In fact it avoids kernel-level scalability impediments
  4028 //      on certain platforms that don't handle lots of active pthread_cond_timedwait()
  4029 //      timers in a graceful fashion.
  4030 //
  4031 // 4.   When the abstime value is in the past it appears that control returns
  4032 //      correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
  4033 //      Subsequent timedwait/wait calls may hang indefinitely.  Given that, we
  4034 //      can avoid the problem by reinitializing the condvar -- by cond_destroy()
  4035 //      followed by cond_init() -- after all calls to pthread_cond_timedwait().
  4036 //      It may be possible to avoid reinitialization by checking the return
  4037 //      value from pthread_cond_timedwait().  In addition to reinitializing the
  4038 //      condvar we must establish the invariant that cond_signal() is only called
  4039 //      within critical sections protected by the adjunct mutex.  This prevents
  4040 //      cond_signal() from "seeing" a condvar that's in the midst of being
  4041 //      reinitialized or that is corrupt.  Sadly, this invariant obviates the
  4042 //      desirable signal-after-unlock optimization that avoids futile context switching.
  4043 //
  4044 //      I'm also concerned that some versions of NTPL might allocate an auxilliary
  4045 //      structure when a condvar is used or initialized.  cond_destroy()  would
  4046 //      release the helper structure.  Our reinitialize-after-timedwait fix
  4047 //      put excessive stress on malloc/free and locks protecting the c-heap.
  4048 //
  4049 // We currently use (4).  See the WorkAroundNTPLTimedWaitHang flag.
  4050 // It may be possible to refine (4) by checking the kernel and NTPL verisons
  4051 // and only enabling the work-around for vulnerable environments.
  4053 // utility to compute the abstime argument to timedwait:
  4054 // millis is the relative timeout time
  4055 // abstime will be the absolute timeout time
  4056 // TODO: replace compute_abstime() with unpackTime()
  4058 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
  4059   if (millis < 0)  millis = 0;
  4060   struct timeval now;
  4061   int status = gettimeofday(&now, NULL);
  4062   assert(status == 0, "gettimeofday");
  4063   jlong seconds = millis / 1000;
  4064   millis %= 1000;
  4065   if (seconds > 50000000) { // see man cond_timedwait(3T)
  4066     seconds = 50000000;
  4068   abstime->tv_sec = now.tv_sec  + seconds;
  4069   long       usec = now.tv_usec + millis * 1000;
  4070   if (usec >= 1000000) {
  4071     abstime->tv_sec += 1;
  4072     usec -= 1000000;
  4074   abstime->tv_nsec = usec * 1000;
  4075   return abstime;
  4079 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
  4080 // Conceptually TryPark() should be equivalent to park(0).
  4082 int os::PlatformEvent::TryPark() {
  4083   for (;;) {
  4084     const int v = _Event ;
  4085     guarantee ((v == 0) || (v == 1), "invariant") ;
  4086     if (Atomic::cmpxchg (0, &_Event, v) == v) return v  ;
  4090 void os::PlatformEvent::park() {       // AKA "down()"
  4091   // Invariant: Only the thread associated with the Event/PlatformEvent
  4092   // may call park().
  4093   // TODO: assert that _Assoc != NULL or _Assoc == Self
  4094   int v ;
  4095   for (;;) {
  4096       v = _Event ;
  4097       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4099   guarantee (v >= 0, "invariant") ;
  4100   if (v == 0) {
  4101      // Do this the hard way by blocking ...
  4102      int status = pthread_mutex_lock(_mutex);
  4103      assert_status(status == 0, status, "mutex_lock");
  4104      guarantee (_nParked == 0, "invariant") ;
  4105      ++ _nParked ;
  4106      while (_Event < 0) {
  4107         status = pthread_cond_wait(_cond, _mutex);
  4108         // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
  4109         // Treat this the same as if the wait was interrupted
  4110         if (status == ETIMEDOUT) { status = EINTR; }
  4111         assert_status(status == 0 || status == EINTR, status, "cond_wait");
  4113      -- _nParked ;
  4115     _Event = 0 ;
  4116      status = pthread_mutex_unlock(_mutex);
  4117      assert_status(status == 0, status, "mutex_unlock");
  4118     // Paranoia to ensure our locked and lock-free paths interact
  4119     // correctly with each other.
  4120     OrderAccess::fence();
  4122   guarantee (_Event >= 0, "invariant") ;
  4125 int os::PlatformEvent::park(jlong millis) {
  4126   guarantee (_nParked == 0, "invariant") ;
  4128   int v ;
  4129   for (;;) {
  4130       v = _Event ;
  4131       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4133   guarantee (v >= 0, "invariant") ;
  4134   if (v != 0) return OS_OK ;
  4136   // We do this the hard way, by blocking the thread.
  4137   // Consider enforcing a minimum timeout value.
  4138   struct timespec abst;
  4139   compute_abstime(&abst, millis);
  4141   int ret = OS_TIMEOUT;
  4142   int status = pthread_mutex_lock(_mutex);
  4143   assert_status(status == 0, status, "mutex_lock");
  4144   guarantee (_nParked == 0, "invariant") ;
  4145   ++_nParked ;
  4147   // Object.wait(timo) will return because of
  4148   // (a) notification
  4149   // (b) timeout
  4150   // (c) thread.interrupt
  4151   //
  4152   // Thread.interrupt and object.notify{All} both call Event::set.
  4153   // That is, we treat thread.interrupt as a special case of notification.
  4154   // The underlying Solaris implementation, cond_timedwait, admits
  4155   // spurious/premature wakeups, but the JLS/JVM spec prevents the
  4156   // JVM from making those visible to Java code.  As such, we must
  4157   // filter out spurious wakeups.  We assume all ETIME returns are valid.
  4158   //
  4159   // TODO: properly differentiate simultaneous notify+interrupt.
  4160   // In that case, we should propagate the notify to another waiter.
  4162   while (_Event < 0) {
  4163     status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
  4164     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4165       pthread_cond_destroy (_cond);
  4166       pthread_cond_init (_cond, NULL) ;
  4168     assert_status(status == 0 || status == EINTR ||
  4169                   status == ETIMEDOUT,
  4170                   status, "cond_timedwait");
  4171     if (!FilterSpuriousWakeups) break ;                 // previous semantics
  4172     if (status == ETIMEDOUT) break ;
  4173     // We consume and ignore EINTR and spurious wakeups.
  4175   --_nParked ;
  4176   if (_Event >= 0) {
  4177      ret = OS_OK;
  4179   _Event = 0 ;
  4180   status = pthread_mutex_unlock(_mutex);
  4181   assert_status(status == 0, status, "mutex_unlock");
  4182   assert (_nParked == 0, "invariant") ;
  4183   // Paranoia to ensure our locked and lock-free paths interact
  4184   // correctly with each other.
  4185   OrderAccess::fence();
  4186   return ret;
  4189 void os::PlatformEvent::unpark() {
  4190   // Transitions for _Event:
  4191   //    0 :=> 1
  4192   //    1 :=> 1
  4193   //   -1 :=> either 0 or 1; must signal target thread
  4194   //          That is, we can safely transition _Event from -1 to either
  4195   //          0 or 1. Forcing 1 is slightly more efficient for back-to-back
  4196   //          unpark() calls.
  4197   // See also: "Semaphores in Plan 9" by Mullender & Cox
  4198   //
  4199   // Note: Forcing a transition from "-1" to "1" on an unpark() means
  4200   // that it will take two back-to-back park() calls for the owning
  4201   // thread to block. This has the benefit of forcing a spurious return
  4202   // from the first park() call after an unpark() call which will help
  4203   // shake out uses of park() and unpark() without condition variables.
  4205   if (Atomic::xchg(1, &_Event) >= 0) return;
  4207   // Wait for the thread associated with the event to vacate
  4208   int status = pthread_mutex_lock(_mutex);
  4209   assert_status(status == 0, status, "mutex_lock");
  4210   int AnyWaiters = _nParked;
  4211   assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
  4212   if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
  4213     AnyWaiters = 0;
  4214     pthread_cond_signal(_cond);
  4216   status = pthread_mutex_unlock(_mutex);
  4217   assert_status(status == 0, status, "mutex_unlock");
  4218   if (AnyWaiters != 0) {
  4219     status = pthread_cond_signal(_cond);
  4220     assert_status(status == 0, status, "cond_signal");
  4223   // Note that we signal() _after dropping the lock for "immortal" Events.
  4224   // This is safe and avoids a common class of  futile wakeups.  In rare
  4225   // circumstances this can cause a thread to return prematurely from
  4226   // cond_{timed}wait() but the spurious wakeup is benign and the victim will
  4227   // simply re-test the condition and re-park itself.
  4231 // JSR166
  4232 // -------------------------------------------------------
  4234 /*
  4235  * The solaris and bsd implementations of park/unpark are fairly
  4236  * conservative for now, but can be improved. They currently use a
  4237  * mutex/condvar pair, plus a a count.
  4238  * Park decrements count if > 0, else does a condvar wait.  Unpark
  4239  * sets count to 1 and signals condvar.  Only one thread ever waits
  4240  * on the condvar. Contention seen when trying to park implies that someone
  4241  * is unparking you, so don't wait. And spurious returns are fine, so there
  4242  * is no need to track notifications.
  4243  */
  4245 #define MAX_SECS 100000000
  4246 /*
  4247  * This code is common to bsd and solaris and will be moved to a
  4248  * common place in dolphin.
  4250  * The passed in time value is either a relative time in nanoseconds
  4251  * or an absolute time in milliseconds. Either way it has to be unpacked
  4252  * into suitable seconds and nanoseconds components and stored in the
  4253  * given timespec structure.
  4254  * Given time is a 64-bit value and the time_t used in the timespec is only
  4255  * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
  4256  * overflow if times way in the future are given. Further on Solaris versions
  4257  * prior to 10 there is a restriction (see cond_timedwait) that the specified
  4258  * number of seconds, in abstime, is less than current_time  + 100,000,000.
  4259  * As it will be 28 years before "now + 100000000" will overflow we can
  4260  * ignore overflow and just impose a hard-limit on seconds using the value
  4261  * of "now + 100,000,000". This places a limit on the timeout of about 3.17
  4262  * years from "now".
  4263  */
  4265 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
  4266   assert (time > 0, "convertTime");
  4268   struct timeval now;
  4269   int status = gettimeofday(&now, NULL);
  4270   assert(status == 0, "gettimeofday");
  4272   time_t max_secs = now.tv_sec + MAX_SECS;
  4274   if (isAbsolute) {
  4275     jlong secs = time / 1000;
  4276     if (secs > max_secs) {
  4277       absTime->tv_sec = max_secs;
  4279     else {
  4280       absTime->tv_sec = secs;
  4282     absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
  4284   else {
  4285     jlong secs = time / NANOSECS_PER_SEC;
  4286     if (secs >= MAX_SECS) {
  4287       absTime->tv_sec = max_secs;
  4288       absTime->tv_nsec = 0;
  4290     else {
  4291       absTime->tv_sec = now.tv_sec + secs;
  4292       absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
  4293       if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
  4294         absTime->tv_nsec -= NANOSECS_PER_SEC;
  4295         ++absTime->tv_sec; // note: this must be <= max_secs
  4299   assert(absTime->tv_sec >= 0, "tv_sec < 0");
  4300   assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
  4301   assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
  4302   assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
  4305 void Parker::park(bool isAbsolute, jlong time) {
  4306   // Ideally we'd do something useful while spinning, such
  4307   // as calling unpackTime().
  4309   // Optional fast-path check:
  4310   // Return immediately if a permit is available.
  4311   // We depend on Atomic::xchg() having full barrier semantics
  4312   // since we are doing a lock-free update to _counter.
  4313   if (Atomic::xchg(0, &_counter) > 0) return;
  4315   Thread* thread = Thread::current();
  4316   assert(thread->is_Java_thread(), "Must be JavaThread");
  4317   JavaThread *jt = (JavaThread *)thread;
  4319   // Optional optimization -- avoid state transitions if there's an interrupt pending.
  4320   // Check interrupt before trying to wait
  4321   if (Thread::is_interrupted(thread, false)) {
  4322     return;
  4325   // Next, demultiplex/decode time arguments
  4326   struct timespec absTime;
  4327   if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
  4328     return;
  4330   if (time > 0) {
  4331     unpackTime(&absTime, isAbsolute, time);
  4335   // Enter safepoint region
  4336   // Beware of deadlocks such as 6317397.
  4337   // The per-thread Parker:: mutex is a classic leaf-lock.
  4338   // In particular a thread must never block on the Threads_lock while
  4339   // holding the Parker:: mutex.  If safepoints are pending both the
  4340   // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
  4341   ThreadBlockInVM tbivm(jt);
  4343   // Don't wait if cannot get lock since interference arises from
  4344   // unblocking.  Also. check interrupt before trying wait
  4345   if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
  4346     return;
  4349   int status ;
  4350   if (_counter > 0)  { // no wait needed
  4351     _counter = 0;
  4352     status = pthread_mutex_unlock(_mutex);
  4353     assert (status == 0, "invariant") ;
  4354     // Paranoia to ensure our locked and lock-free paths interact
  4355     // correctly with each other and Java-level accesses.
  4356     OrderAccess::fence();
  4357     return;
  4360 #ifdef ASSERT
  4361   // Don't catch signals while blocked; let the running threads have the signals.
  4362   // (This allows a debugger to break into the running thread.)
  4363   sigset_t oldsigs;
  4364   sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
  4365   pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
  4366 #endif
  4368   OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  4369   jt->set_suspend_equivalent();
  4370   // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  4372   if (time == 0) {
  4373     status = pthread_cond_wait (_cond, _mutex) ;
  4374   } else {
  4375     status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
  4376     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4377       pthread_cond_destroy (_cond) ;
  4378       pthread_cond_init    (_cond, NULL);
  4381   assert_status(status == 0 || status == EINTR ||
  4382                 status == ETIMEDOUT,
  4383                 status, "cond_timedwait");
  4385 #ifdef ASSERT
  4386   pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
  4387 #endif
  4389   _counter = 0 ;
  4390   status = pthread_mutex_unlock(_mutex) ;
  4391   assert_status(status == 0, status, "invariant") ;
  4392   // Paranoia to ensure our locked and lock-free paths interact
  4393   // correctly with each other and Java-level accesses.
  4394   OrderAccess::fence();
  4396   // If externally suspended while waiting, re-suspend
  4397   if (jt->handle_special_suspend_equivalent_condition()) {
  4398     jt->java_suspend_self();
  4402 void Parker::unpark() {
  4403   int s, status ;
  4404   status = pthread_mutex_lock(_mutex);
  4405   assert (status == 0, "invariant") ;
  4406   s = _counter;
  4407   _counter = 1;
  4408   if (s < 1) {
  4409      if (WorkAroundNPTLTimedWaitHang) {
  4410         status = pthread_cond_signal (_cond) ;
  4411         assert (status == 0, "invariant") ;
  4412         status = pthread_mutex_unlock(_mutex);
  4413         assert (status == 0, "invariant") ;
  4414      } else {
  4415         status = pthread_mutex_unlock(_mutex);
  4416         assert (status == 0, "invariant") ;
  4417         status = pthread_cond_signal (_cond) ;
  4418         assert (status == 0, "invariant") ;
  4420   } else {
  4421     pthread_mutex_unlock(_mutex);
  4422     assert (status == 0, "invariant") ;
  4427 /* Darwin has no "environ" in a dynamic library. */
  4428 #ifdef __APPLE__
  4429 #include <crt_externs.h>
  4430 #define environ (*_NSGetEnviron())
  4431 #else
  4432 extern char** environ;
  4433 #endif
  4435 // Run the specified command in a separate process. Return its exit value,
  4436 // or -1 on failure (e.g. can't fork a new process).
  4437 // Unlike system(), this function can be called from signal handler. It
  4438 // doesn't block SIGINT et al.
  4439 int os::fork_and_exec(char* cmd) {
  4440   const char * argv[4] = {"sh", "-c", cmd, NULL};
  4442   // fork() in BsdThreads/NPTL is not async-safe. It needs to run
  4443   // pthread_atfork handlers and reset pthread library. All we need is a
  4444   // separate process to execve. Make a direct syscall to fork process.
  4445   // On IA64 there's no fork syscall, we have to use fork() and hope for
  4446   // the best...
  4447   pid_t pid = fork();
  4449   if (pid < 0) {
  4450     // fork failed
  4451     return -1;
  4453   } else if (pid == 0) {
  4454     // child process
  4456     // execve() in BsdThreads will call pthread_kill_other_threads_np()
  4457     // first to kill every thread on the thread list. Because this list is
  4458     // not reset by fork() (see notes above), execve() will instead kill
  4459     // every thread in the parent process. We know this is the only thread
  4460     // in the new process, so make a system call directly.
  4461     // IA64 should use normal execve() from glibc to match the glibc fork()
  4462     // above.
  4463     execve("/bin/sh", (char* const*)argv, environ);
  4465     // execve failed
  4466     _exit(-1);
  4468   } else  {
  4469     // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
  4470     // care about the actual exit code, for now.
  4472     int status;
  4474     // Wait for the child process to exit.  This returns immediately if
  4475     // the child has already exited. */
  4476     while (waitpid(pid, &status, 0) < 0) {
  4477         switch (errno) {
  4478         case ECHILD: return 0;
  4479         case EINTR: break;
  4480         default: return -1;
  4484     if (WIFEXITED(status)) {
  4485        // The child exited normally; get its exit code.
  4486        return WEXITSTATUS(status);
  4487     } else if (WIFSIGNALED(status)) {
  4488        // The child exited because of a signal
  4489        // The best value to return is 0x80 + signal number,
  4490        // because that is what all Unix shells do, and because
  4491        // it allows callers to distinguish between process exit and
  4492        // process death by signal.
  4493        return 0x80 + WTERMSIG(status);
  4494     } else {
  4495        // Unknown exit code; pass it through
  4496        return status;
  4501 // is_headless_jre()
  4502 //
  4503 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
  4504 // in order to report if we are running in a headless jre
  4505 //
  4506 // Since JDK8 xawt/libmawt.so was moved into the same directory
  4507 // as libawt.so, and renamed libawt_xawt.so
  4508 //
  4509 bool os::is_headless_jre() {
  4510     struct stat statbuf;
  4511     char buf[MAXPATHLEN];
  4512     char libmawtpath[MAXPATHLEN];
  4513     const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
  4514     const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
  4515     char *p;
  4517     // Get path to libjvm.so
  4518     os::jvm_path(buf, sizeof(buf));
  4520     // Get rid of libjvm.so
  4521     p = strrchr(buf, '/');
  4522     if (p == NULL) return false;
  4523     else *p = '\0';
  4525     // Get rid of client or server
  4526     p = strrchr(buf, '/');
  4527     if (p == NULL) return false;
  4528     else *p = '\0';
  4530     // check xawt/libmawt.so
  4531     strcpy(libmawtpath, buf);
  4532     strcat(libmawtpath, xawtstr);
  4533     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4535     // check libawt_xawt.so
  4536     strcpy(libmawtpath, buf);
  4537     strcat(libmawtpath, new_xawtstr);
  4538     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4540     return true;
  4543 // Get the default path to the core file
  4544 // Returns the length of the string
  4545 int os::get_core_path(char* buffer, size_t bufferSize) {
  4546   int n = jio_snprintf(buffer, bufferSize, "/cores");
  4548   // Truncate if theoretical string was longer than bufferSize
  4549   n = MIN2(n, (int)bufferSize);
  4551   return n;

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