src/os/bsd/vm/os_bsd.cpp

Thu, 03 Oct 2013 12:39:58 +0400

author
dsamersoff
date
Thu, 03 Oct 2013 12:39:58 +0400
changeset 5834
faff125a1ead
parent 5830
2bd38d594b9a
child 5895
3e265ce4d2dd
permissions
-rw-r--r--

8022616: u4 should not be used as a type for thread_id
Summary: Usage of u4 as a type for thread_id cause a compilation error on platform, where thread_id is a pointer
Reviewed-by: sla, sspitsyn, minqi

     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>
   103 # include <sys/syscall.h>
   105 #if defined(__FreeBSD__) || defined(__NetBSD__)
   106 # include <elf.h>
   107 #endif
   109 #ifdef __APPLE__
   110 # include <mach/mach.h> // semaphore_* API
   111 # include <mach-o/dyld.h>
   112 # include <sys/proc_info.h>
   113 # include <objc/objc-auto.h>
   114 #endif
   116 #ifndef MAP_ANONYMOUS
   117 #define MAP_ANONYMOUS MAP_ANON
   118 #endif
   120 #define MAX_PATH    (2 * K)
   122 // for timer info max values which include all bits
   123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
   125 #define LARGEPAGES_BIT (1 << 6)
   126 ////////////////////////////////////////////////////////////////////////////////
   127 // global variables
   128 julong os::Bsd::_physical_memory = 0;
   131 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
   132 pthread_t os::Bsd::_main_thread;
   133 int os::Bsd::_page_size = -1;
   135 static jlong initial_time_count=0;
   137 static int clock_tics_per_sec = 100;
   139 // For diagnostics to print a message once. see run_periodic_checks
   140 static sigset_t check_signal_done;
   141 static bool check_signals = true;
   143 static pid_t _initial_pid = 0;
   145 /* Signal number used to suspend/resume a thread */
   147 /* do not use any signal number less than SIGSEGV, see 4355769 */
   148 static int SR_signum = SIGUSR2;
   149 sigset_t SR_sigset;
   152 ////////////////////////////////////////////////////////////////////////////////
   153 // utility functions
   155 static int SR_initialize();
   156 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
   158 julong os::available_memory() {
   159   return Bsd::available_memory();
   160 }
   162 julong os::Bsd::available_memory() {
   163   // XXXBSD: this is just a stopgap implementation
   164   return physical_memory() >> 2;
   165 }
   167 julong os::physical_memory() {
   168   return Bsd::physical_memory();
   169 }
   171 ////////////////////////////////////////////////////////////////////////////////
   172 // environment support
   174 bool os::getenv(const char* name, char* buf, int len) {
   175   const char* val = ::getenv(name);
   176   if (val != NULL && strlen(val) < (size_t)len) {
   177     strcpy(buf, val);
   178     return true;
   179   }
   180   if (len > 0) buf[0] = 0;  // return a null string
   181   return false;
   182 }
   185 // Return true if user is running as root.
   187 bool os::have_special_privileges() {
   188   static bool init = false;
   189   static bool privileges = false;
   190   if (!init) {
   191     privileges = (getuid() != geteuid()) || (getgid() != getegid());
   192     init = true;
   193   }
   194   return privileges;
   195 }
   199 // Cpu architecture string
   200 #if   defined(ZERO)
   201 static char cpu_arch[] = ZERO_LIBARCH;
   202 #elif defined(IA64)
   203 static char cpu_arch[] = "ia64";
   204 #elif defined(IA32)
   205 static char cpu_arch[] = "i386";
   206 #elif defined(AMD64)
   207 static char cpu_arch[] = "amd64";
   208 #elif defined(ARM)
   209 static char cpu_arch[] = "arm";
   210 #elif defined(PPC)
   211 static char cpu_arch[] = "ppc";
   212 #elif defined(SPARC)
   213 #  ifdef _LP64
   214 static char cpu_arch[] = "sparcv9";
   215 #  else
   216 static char cpu_arch[] = "sparc";
   217 #  endif
   218 #else
   219 #error Add appropriate cpu_arch setting
   220 #endif
   222 // Compiler variant
   223 #ifdef COMPILER2
   224 #define COMPILER_VARIANT "server"
   225 #else
   226 #define COMPILER_VARIANT "client"
   227 #endif
   230 void os::Bsd::initialize_system_info() {
   231   int mib[2];
   232   size_t len;
   233   int cpu_val;
   234   julong mem_val;
   236   /* get processors count via hw.ncpus sysctl */
   237   mib[0] = CTL_HW;
   238   mib[1] = HW_NCPU;
   239   len = sizeof(cpu_val);
   240   if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
   241        assert(len == sizeof(cpu_val), "unexpected data size");
   242        set_processor_count(cpu_val);
   243   }
   244   else {
   245        set_processor_count(1);   // fallback
   246   }
   248   /* get physical memory via hw.memsize sysctl (hw.memsize is used
   249    * since it returns a 64 bit value)
   250    */
   251   mib[0] = CTL_HW;
   253 #if defined (HW_MEMSIZE) // Apple
   254   mib[1] = HW_MEMSIZE;
   255 #elif defined(HW_PHYSMEM) // Most of BSD
   256   mib[1] = HW_PHYSMEM;
   257 #elif defined(HW_REALMEM) // Old FreeBSD
   258   mib[1] = HW_REALMEM;
   259 #else
   260   #error No ways to get physmem
   261 #endif
   263   len = sizeof(mem_val);
   264   if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
   265        assert(len == sizeof(mem_val), "unexpected data size");
   266        _physical_memory = mem_val;
   267   } else {
   268        _physical_memory = 256*1024*1024;       // fallback (XXXBSD?)
   269   }
   271 #ifdef __OpenBSD__
   272   {
   273        // limit _physical_memory memory view on OpenBSD since
   274        // datasize rlimit restricts us anyway.
   275        struct rlimit limits;
   276        getrlimit(RLIMIT_DATA, &limits);
   277        _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
   278   }
   279 #endif
   280 }
   282 #ifdef __APPLE__
   283 static const char *get_home() {
   284   const char *home_dir = ::getenv("HOME");
   285   if ((home_dir == NULL) || (*home_dir == '\0')) {
   286     struct passwd *passwd_info = getpwuid(geteuid());
   287     if (passwd_info != NULL) {
   288       home_dir = passwd_info->pw_dir;
   289     }
   290   }
   292   return home_dir;
   293 }
   294 #endif
   296 void os::init_system_properties_values() {
   297 //  char arch[12];
   298 //  sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
   300   // The next steps are taken in the product version:
   301   //
   302   // Obtain the JAVA_HOME value from the location of libjvm.so.
   303   // This library should be located at:
   304   // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
   305   //
   306   // If "/jre/lib/" appears at the right place in the path, then we
   307   // assume libjvm.so is installed in a JDK and we use this path.
   308   //
   309   // Otherwise exit with message: "Could not create the Java virtual machine."
   310   //
   311   // The following extra steps are taken in the debugging version:
   312   //
   313   // If "/jre/lib/" does NOT appear at the right place in the path
   314   // instead of exit check for $JAVA_HOME environment variable.
   315   //
   316   // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
   317   // then we append a fake suffix "hotspot/libjvm.so" to this path so
   318   // it looks like libjvm.so is installed there
   319   // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
   320   //
   321   // Otherwise exit.
   322   //
   323   // Important note: if the location of libjvm.so changes this
   324   // code needs to be changed accordingly.
   326   // The next few definitions allow the code to be verbatim:
   327 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
   328 #define getenv(n) ::getenv(n)
   330 /*
   331  * See ld(1):
   332  *      The linker uses the following search paths to locate required
   333  *      shared libraries:
   334  *        1: ...
   335  *        ...
   336  *        7: The default directories, normally /lib and /usr/lib.
   337  */
   338 #ifndef DEFAULT_LIBPATH
   339 #define DEFAULT_LIBPATH "/lib:/usr/lib"
   340 #endif
   342 #define EXTENSIONS_DIR  "/lib/ext"
   343 #define ENDORSED_DIR    "/lib/endorsed"
   344 #define REG_DIR         "/usr/java/packages"
   346 #ifdef __APPLE__
   347 #define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
   348 #define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
   349         const char *user_home_dir = get_home();
   350         // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
   351         int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
   352             sizeof(SYS_EXTENSIONS_DIRS);
   353 #endif
   355   {
   356     /* sysclasspath, java_home, dll_dir */
   357     {
   358         char *home_path;
   359         char *dll_path;
   360         char *pslash;
   361         char buf[MAXPATHLEN];
   362         os::jvm_path(buf, sizeof(buf));
   364         // Found the full path to libjvm.so.
   365         // Now cut the path to <java_home>/jre if we can.
   366         *(strrchr(buf, '/')) = '\0';  /* get rid of /libjvm.so */
   367         pslash = strrchr(buf, '/');
   368         if (pslash != NULL)
   369             *pslash = '\0';           /* get rid of /{client|server|hotspot} */
   370         dll_path = malloc(strlen(buf) + 1);
   371         if (dll_path == NULL)
   372             return;
   373         strcpy(dll_path, buf);
   374         Arguments::set_dll_dir(dll_path);
   376         if (pslash != NULL) {
   377             pslash = strrchr(buf, '/');
   378             if (pslash != NULL) {
   379                 *pslash = '\0';       /* get rid of /<arch> (/lib on macosx) */
   380 #ifndef __APPLE__
   381                 pslash = strrchr(buf, '/');
   382                 if (pslash != NULL)
   383                     *pslash = '\0';   /* get rid of /lib */
   384 #endif
   385             }
   386         }
   388         home_path = malloc(strlen(buf) + 1);
   389         if (home_path == NULL)
   390             return;
   391         strcpy(home_path, buf);
   392         Arguments::set_java_home(home_path);
   394         if (!set_boot_path('/', ':'))
   395             return;
   396     }
   398     /*
   399      * Where to look for native libraries
   400      *
   401      * Note: Due to a legacy implementation, most of the library path
   402      * is set in the launcher.  This was to accomodate linking restrictions
   403      * on legacy Bsd implementations (which are no longer supported).
   404      * Eventually, all the library path setting will be done here.
   405      *
   406      * However, to prevent the proliferation of improperly built native
   407      * libraries, the new path component /usr/java/packages is added here.
   408      * Eventually, all the library path setting will be done here.
   409      */
   410     {
   411         char *ld_library_path;
   413         /*
   414          * Construct the invariant part of ld_library_path. Note that the
   415          * space for the colon and the trailing null are provided by the
   416          * nulls included by the sizeof operator (so actually we allocate
   417          * a byte more than necessary).
   418          */
   419 #ifdef __APPLE__
   420         ld_library_path = (char *) malloc(system_ext_size);
   421         sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
   422 #else
   423         ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
   424             strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
   425         sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
   426 #endif
   428         /*
   429          * Get the user setting of LD_LIBRARY_PATH, and prepended it.  It
   430          * should always exist (until the legacy problem cited above is
   431          * addressed).
   432          */
   433 #ifdef __APPLE__
   434         // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
   435         char *l = getenv("JAVA_LIBRARY_PATH");
   436         if (l != 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(l) + 1 + strlen(t) + 1);
   440             sprintf(ld_library_path, "%s:%s", l, t);
   441             free(t);
   442         }
   444         char *v = getenv("DYLD_LIBRARY_PATH");
   445 #else
   446         char *v = getenv("LD_LIBRARY_PATH");
   447 #endif
   448         if (v != NULL) {
   449             char *t = ld_library_path;
   450             /* That's +1 for the colon and +1 for the trailing '\0' */
   451             ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
   452             sprintf(ld_library_path, "%s:%s", v, t);
   453             free(t);
   454         }
   456 #ifdef __APPLE__
   457         // Apple's Java6 has "." at the beginning of java.library.path.
   458         // OpenJDK on Windows has "." at the end of java.library.path.
   459         // OpenJDK on Linux and Solaris don't have "." in java.library.path
   460         // at all. To ease the transition from Apple's Java6 to OpenJDK7,
   461         // "." is appended to the end of java.library.path. Yes, this
   462         // could cause a change in behavior, but Apple's Java6 behavior
   463         // can be achieved by putting "." at the beginning of the
   464         // JAVA_LIBRARY_PATH environment variable.
   465         {
   466             char *t = ld_library_path;
   467             // that's +3 for appending ":." and the trailing '\0'
   468             ld_library_path = (char *) malloc(strlen(t) + 3);
   469             sprintf(ld_library_path, "%s:%s", t, ".");
   470             free(t);
   471         }
   472 #endif
   474         Arguments::set_library_path(ld_library_path);
   475     }
   477     /*
   478      * Extensions directories.
   479      *
   480      * Note that the space for the colon and the trailing null are provided
   481      * by the nulls included by the sizeof operator (so actually one byte more
   482      * than necessary is allocated).
   483      */
   484     {
   485 #ifdef __APPLE__
   486         char *buf = malloc(strlen(Arguments::get_java_home()) +
   487             sizeof(EXTENSIONS_DIR) + system_ext_size);
   488         sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
   489             SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
   490 #else
   491         char *buf = malloc(strlen(Arguments::get_java_home()) +
   492             sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
   493         sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
   494             Arguments::get_java_home());
   495 #endif
   497         Arguments::set_ext_dirs(buf);
   498     }
   500     /* Endorsed standards default directory. */
   501     {
   502         char * buf;
   503         buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
   504         sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
   505         Arguments::set_endorsed_dirs(buf);
   506     }
   507   }
   509 #ifdef __APPLE__
   510 #undef SYS_EXTENSIONS_DIR
   511 #endif
   512 #undef malloc
   513 #undef getenv
   514 #undef EXTENSIONS_DIR
   515 #undef ENDORSED_DIR
   517   // Done
   518   return;
   519 }
   521 ////////////////////////////////////////////////////////////////////////////////
   522 // breakpoint support
   524 void os::breakpoint() {
   525   BREAKPOINT;
   526 }
   528 extern "C" void breakpoint() {
   529   // use debugger to set breakpoint here
   530 }
   532 ////////////////////////////////////////////////////////////////////////////////
   533 // signal support
   535 debug_only(static bool signal_sets_initialized = false);
   536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
   538 bool os::Bsd::is_sig_ignored(int sig) {
   539       struct sigaction oact;
   540       sigaction(sig, (struct sigaction*)NULL, &oact);
   541       void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
   542                                      : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
   543       if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
   544            return true;
   545       else
   546            return false;
   547 }
   549 void os::Bsd::signal_sets_init() {
   550   // Should also have an assertion stating we are still single-threaded.
   551   assert(!signal_sets_initialized, "Already initialized");
   552   // Fill in signals that are necessarily unblocked for all threads in
   553   // the VM. Currently, we unblock the following signals:
   554   // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
   555   //                         by -Xrs (=ReduceSignalUsage));
   556   // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
   557   // other threads. The "ReduceSignalUsage" boolean tells us not to alter
   558   // the dispositions or masks wrt these signals.
   559   // Programs embedding the VM that want to use the above signals for their
   560   // own purposes must, at this time, use the "-Xrs" option to prevent
   561   // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
   562   // (See bug 4345157, and other related bugs).
   563   // In reality, though, unblocking these signals is really a nop, since
   564   // these signals are not blocked by default.
   565   sigemptyset(&unblocked_sigs);
   566   sigemptyset(&allowdebug_blocked_sigs);
   567   sigaddset(&unblocked_sigs, SIGILL);
   568   sigaddset(&unblocked_sigs, SIGSEGV);
   569   sigaddset(&unblocked_sigs, SIGBUS);
   570   sigaddset(&unblocked_sigs, SIGFPE);
   571   sigaddset(&unblocked_sigs, SR_signum);
   573   if (!ReduceSignalUsage) {
   574    if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
   575       sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
   576       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
   577    }
   578    if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
   579       sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
   580       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
   581    }
   582    if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
   583       sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
   584       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
   585    }
   586   }
   587   // Fill in signals that are blocked by all but the VM thread.
   588   sigemptyset(&vm_sigs);
   589   if (!ReduceSignalUsage)
   590     sigaddset(&vm_sigs, BREAK_SIGNAL);
   591   debug_only(signal_sets_initialized = true);
   593 }
   595 // These are signals that are unblocked while a thread is running Java.
   596 // (For some reason, they get blocked by default.)
   597 sigset_t* os::Bsd::unblocked_signals() {
   598   assert(signal_sets_initialized, "Not initialized");
   599   return &unblocked_sigs;
   600 }
   602 // These are the signals that are blocked while a (non-VM) thread is
   603 // running Java. Only the VM thread handles these signals.
   604 sigset_t* os::Bsd::vm_signals() {
   605   assert(signal_sets_initialized, "Not initialized");
   606   return &vm_sigs;
   607 }
   609 // These are signals that are blocked during cond_wait to allow debugger in
   610 sigset_t* os::Bsd::allowdebug_blocked_signals() {
   611   assert(signal_sets_initialized, "Not initialized");
   612   return &allowdebug_blocked_sigs;
   613 }
   615 void os::Bsd::hotspot_sigmask(Thread* thread) {
   617   //Save caller's signal mask before setting VM signal mask
   618   sigset_t caller_sigmask;
   619   pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
   621   OSThread* osthread = thread->osthread();
   622   osthread->set_caller_sigmask(caller_sigmask);
   624   pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
   626   if (!ReduceSignalUsage) {
   627     if (thread->is_VM_thread()) {
   628       // Only the VM thread handles BREAK_SIGNAL ...
   629       pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
   630     } else {
   631       // ... all other threads block BREAK_SIGNAL
   632       pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
   633     }
   634   }
   635 }
   638 //////////////////////////////////////////////////////////////////////////////
   639 // create new thread
   641 // check if it's safe to start a new thread
   642 static bool _thread_safety_check(Thread* thread) {
   643   return true;
   644 }
   646 #ifdef __APPLE__
   647 // library handle for calling objc_registerThreadWithCollector()
   648 // without static linking to the libobjc library
   649 #define OBJC_LIB "/usr/lib/libobjc.dylib"
   650 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
   651 typedef void (*objc_registerThreadWithCollector_t)();
   652 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
   653 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
   654 #endif
   656 #ifdef __APPLE__
   657 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
   658   // Additional thread_id used to correlate threads in SA
   659   thread_identifier_info_data_t     m_ident_info;
   660   mach_msg_type_number_t            count = THREAD_IDENTIFIER_INFO_COUNT;
   662   thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
   663               (thread_info_t) &m_ident_info, &count);
   665   return m_ident_info.thread_id;
   666 }
   667 #endif
   669 // Thread start routine for all newly created threads
   670 static void *java_start(Thread *thread) {
   671   // Try to randomize the cache line index of hot stack frames.
   672   // This helps when threads of the same stack traces evict each other's
   673   // cache lines. The threads can be either from the same JVM instance, or
   674   // from different JVM instances. The benefit is especially true for
   675   // processors with hyperthreading technology.
   676   static int counter = 0;
   677   int pid = os::current_process_id();
   678   alloca(((pid ^ counter++) & 7) * 128);
   680   ThreadLocalStorage::set_thread(thread);
   682   OSThread* osthread = thread->osthread();
   683   Monitor* sync = osthread->startThread_lock();
   685   // non floating stack BsdThreads needs extra check, see above
   686   if (!_thread_safety_check(thread)) {
   687     // notify parent thread
   688     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   689     osthread->set_state(ZOMBIE);
   690     sync->notify_all();
   691     return NULL;
   692   }
   694   osthread->set_thread_id(os::Bsd::gettid());
   696 #ifdef __APPLE__
   697   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
   698   guarantee(unique_thread_id != 0, "unique thread id was not found");
   699   osthread->set_unique_thread_id(unique_thread_id);
   700 #endif
   701   // initialize signal mask for this thread
   702   os::Bsd::hotspot_sigmask(thread);
   704   // initialize floating point control register
   705   os::Bsd::init_thread_fpu_state();
   707 #ifdef __APPLE__
   708   // register thread with objc gc
   709   if (objc_registerThreadWithCollectorFunction != NULL) {
   710     objc_registerThreadWithCollectorFunction();
   711   }
   712 #endif
   714   // handshaking with parent thread
   715   {
   716     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   718     // notify parent thread
   719     osthread->set_state(INITIALIZED);
   720     sync->notify_all();
   722     // wait until os::start_thread()
   723     while (osthread->get_state() == INITIALIZED) {
   724       sync->wait(Mutex::_no_safepoint_check_flag);
   725     }
   726   }
   728   // call one more level start routine
   729   thread->run();
   731   return 0;
   732 }
   734 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
   735   assert(thread->osthread() == NULL, "caller responsible");
   737   // Allocate the OSThread object
   738   OSThread* osthread = new OSThread(NULL, NULL);
   739   if (osthread == NULL) {
   740     return false;
   741   }
   743   // set the correct thread state
   744   osthread->set_thread_type(thr_type);
   746   // Initial state is ALLOCATED but not INITIALIZED
   747   osthread->set_state(ALLOCATED);
   749   thread->set_osthread(osthread);
   751   // init thread attributes
   752   pthread_attr_t attr;
   753   pthread_attr_init(&attr);
   754   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
   756   // stack size
   757   if (os::Bsd::supports_variable_stack_size()) {
   758     // calculate stack size if it's not specified by caller
   759     if (stack_size == 0) {
   760       stack_size = os::Bsd::default_stack_size(thr_type);
   762       switch (thr_type) {
   763       case os::java_thread:
   764         // Java threads use ThreadStackSize which default value can be
   765         // changed with the flag -Xss
   766         assert (JavaThread::stack_size_at_create() > 0, "this should be set");
   767         stack_size = JavaThread::stack_size_at_create();
   768         break;
   769       case os::compiler_thread:
   770         if (CompilerThreadStackSize > 0) {
   771           stack_size = (size_t)(CompilerThreadStackSize * K);
   772           break;
   773         } // else fall through:
   774           // use VMThreadStackSize if CompilerThreadStackSize is not defined
   775       case os::vm_thread:
   776       case os::pgc_thread:
   777       case os::cgc_thread:
   778       case os::watcher_thread:
   779         if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
   780         break;
   781       }
   782     }
   784     stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
   785     pthread_attr_setstacksize(&attr, stack_size);
   786   } else {
   787     // let pthread_create() pick the default value.
   788   }
   790   ThreadState state;
   792   {
   793     pthread_t tid;
   794     int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
   796     pthread_attr_destroy(&attr);
   798     if (ret != 0) {
   799       if (PrintMiscellaneous && (Verbose || WizardMode)) {
   800         perror("pthread_create()");
   801       }
   802       // Need to clean up stuff we've allocated so far
   803       thread->set_osthread(NULL);
   804       delete osthread;
   805       return false;
   806     }
   808     // Store pthread info into the OSThread
   809     osthread->set_pthread_id(tid);
   811     // Wait until child thread is either initialized or aborted
   812     {
   813       Monitor* sync_with_child = osthread->startThread_lock();
   814       MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   815       while ((state = osthread->get_state()) == ALLOCATED) {
   816         sync_with_child->wait(Mutex::_no_safepoint_check_flag);
   817       }
   818     }
   820   }
   822   // Aborted due to thread limit being reached
   823   if (state == ZOMBIE) {
   824       thread->set_osthread(NULL);
   825       delete osthread;
   826       return false;
   827   }
   829   // The thread is returned suspended (in state INITIALIZED),
   830   // and is started higher up in the call chain
   831   assert(state == INITIALIZED, "race condition");
   832   return true;
   833 }
   835 /////////////////////////////////////////////////////////////////////////////
   836 // attach existing thread
   838 // bootstrap the main thread
   839 bool os::create_main_thread(JavaThread* thread) {
   840   assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
   841   return create_attached_thread(thread);
   842 }
   844 bool os::create_attached_thread(JavaThread* thread) {
   845 #ifdef ASSERT
   846     thread->verify_not_published();
   847 #endif
   849   // Allocate the OSThread object
   850   OSThread* osthread = new OSThread(NULL, NULL);
   852   if (osthread == NULL) {
   853     return false;
   854   }
   856   osthread->set_thread_id(os::Bsd::gettid());
   858   // Store pthread info into the OSThread
   859 #ifdef __APPLE__
   860   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
   861   guarantee(unique_thread_id != 0, "just checking");
   862   osthread->set_unique_thread_id(unique_thread_id);
   863 #endif
   864   osthread->set_pthread_id(::pthread_self());
   866   // initialize floating point control register
   867   os::Bsd::init_thread_fpu_state();
   869   // Initial thread state is RUNNABLE
   870   osthread->set_state(RUNNABLE);
   872   thread->set_osthread(osthread);
   874   // initialize signal mask for this thread
   875   // and save the caller's signal mask
   876   os::Bsd::hotspot_sigmask(thread);
   878   return true;
   879 }
   881 void os::pd_start_thread(Thread* thread) {
   882   OSThread * osthread = thread->osthread();
   883   assert(osthread->get_state() != INITIALIZED, "just checking");
   884   Monitor* sync_with_child = osthread->startThread_lock();
   885   MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   886   sync_with_child->notify();
   887 }
   889 // Free Bsd resources related to the OSThread
   890 void os::free_thread(OSThread* osthread) {
   891   assert(osthread != NULL, "osthread not set");
   893   if (Thread::current()->osthread() == osthread) {
   894     // Restore caller's signal mask
   895     sigset_t sigmask = osthread->caller_sigmask();
   896     pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
   897    }
   899   delete osthread;
   900 }
   902 //////////////////////////////////////////////////////////////////////////////
   903 // thread local storage
   905 int os::allocate_thread_local_storage() {
   906   pthread_key_t key;
   907   int rslt = pthread_key_create(&key, NULL);
   908   assert(rslt == 0, "cannot allocate thread local storage");
   909   return (int)key;
   910 }
   912 // Note: This is currently not used by VM, as we don't destroy TLS key
   913 // on VM exit.
   914 void os::free_thread_local_storage(int index) {
   915   int rslt = pthread_key_delete((pthread_key_t)index);
   916   assert(rslt == 0, "invalid index");
   917 }
   919 void os::thread_local_storage_at_put(int index, void* value) {
   920   int rslt = pthread_setspecific((pthread_key_t)index, value);
   921   assert(rslt == 0, "pthread_setspecific failed");
   922 }
   924 extern "C" Thread* get_thread() {
   925   return ThreadLocalStorage::thread();
   926 }
   929 ////////////////////////////////////////////////////////////////////////////////
   930 // time support
   932 // Time since start-up in seconds to a fine granularity.
   933 // Used by VMSelfDestructTimer and the MemProfiler.
   934 double os::elapsedTime() {
   936   return (double)(os::elapsed_counter()) * 0.000001;
   937 }
   939 jlong os::elapsed_counter() {
   940   timeval time;
   941   int status = gettimeofday(&time, NULL);
   942   return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
   943 }
   945 jlong os::elapsed_frequency() {
   946   return (1000 * 1000);
   947 }
   949 bool os::supports_vtime() { return true; }
   950 bool os::enable_vtime()   { return false; }
   951 bool os::vtime_enabled()  { return false; }
   953 double os::elapsedVTime() {
   954   // better than nothing, but not much
   955   return elapsedTime();
   956 }
   958 jlong os::javaTimeMillis() {
   959   timeval time;
   960   int status = gettimeofday(&time, NULL);
   961   assert(status != -1, "bsd error");
   962   return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
   963 }
   965 #ifndef CLOCK_MONOTONIC
   966 #define CLOCK_MONOTONIC (1)
   967 #endif
   969 #ifdef __APPLE__
   970 void os::Bsd::clock_init() {
   971         // XXXDARWIN: Investigate replacement monotonic clock
   972 }
   973 #else
   974 void os::Bsd::clock_init() {
   975   struct timespec res;
   976   struct timespec tp;
   977   if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
   978       ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
   979     // yes, monotonic clock is supported
   980     _clock_gettime = ::clock_gettime;
   981   }
   982 }
   983 #endif
   986 jlong os::javaTimeNanos() {
   987   if (Bsd::supports_monotonic_clock()) {
   988     struct timespec tp;
   989     int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
   990     assert(status == 0, "gettime error");
   991     jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
   992     return result;
   993   } else {
   994     timeval time;
   995     int status = gettimeofday(&time, NULL);
   996     assert(status != -1, "bsd error");
   997     jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
   998     return 1000 * usecs;
   999   }
  1002 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
  1003   if (Bsd::supports_monotonic_clock()) {
  1004     info_ptr->max_value = ALL_64_BITS;
  1006     // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
  1007     info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
  1008     info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
  1009   } else {
  1010     // gettimeofday - based on time in seconds since the Epoch thus does not wrap
  1011     info_ptr->max_value = ALL_64_BITS;
  1013     // gettimeofday is a real time clock so it skips
  1014     info_ptr->may_skip_backward = true;
  1015     info_ptr->may_skip_forward = true;
  1018   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
  1021 // Return the real, user, and system times in seconds from an
  1022 // arbitrary fixed point in the past.
  1023 bool os::getTimesSecs(double* process_real_time,
  1024                       double* process_user_time,
  1025                       double* process_system_time) {
  1026   struct tms ticks;
  1027   clock_t real_ticks = times(&ticks);
  1029   if (real_ticks == (clock_t) (-1)) {
  1030     return false;
  1031   } else {
  1032     double ticks_per_second = (double) clock_tics_per_sec;
  1033     *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
  1034     *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
  1035     *process_real_time = ((double) real_ticks) / ticks_per_second;
  1037     return true;
  1042 char * os::local_time_string(char *buf, size_t buflen) {
  1043   struct tm t;
  1044   time_t long_time;
  1045   time(&long_time);
  1046   localtime_r(&long_time, &t);
  1047   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
  1048                t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
  1049                t.tm_hour, t.tm_min, t.tm_sec);
  1050   return buf;
  1053 struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
  1054   return localtime_r(clock, res);
  1057 ////////////////////////////////////////////////////////////////////////////////
  1058 // runtime exit support
  1060 // Note: os::shutdown() might be called very early during initialization, or
  1061 // called from signal handler. Before adding something to os::shutdown(), make
  1062 // sure it is async-safe and can handle partially initialized VM.
  1063 void os::shutdown() {
  1065   // allow PerfMemory to attempt cleanup of any persistent resources
  1066   perfMemory_exit();
  1068   // needs to remove object in file system
  1069   AttachListener::abort();
  1071   // flush buffered output, finish log files
  1072   ostream_abort();
  1074   // Check for abort hook
  1075   abort_hook_t abort_hook = Arguments::abort_hook();
  1076   if (abort_hook != NULL) {
  1077     abort_hook();
  1082 // Note: os::abort() might be called very early during initialization, or
  1083 // called from signal handler. Before adding something to os::abort(), make
  1084 // sure it is async-safe and can handle partially initialized VM.
  1085 void os::abort(bool dump_core) {
  1086   os::shutdown();
  1087   if (dump_core) {
  1088 #ifndef PRODUCT
  1089     fdStream out(defaultStream::output_fd());
  1090     out.print_raw("Current thread is ");
  1091     char buf[16];
  1092     jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
  1093     out.print_raw_cr(buf);
  1094     out.print_raw_cr("Dumping core ...");
  1095 #endif
  1096     ::abort(); // dump core
  1099   ::exit(1);
  1102 // Die immediately, no exit hook, no abort hook, no cleanup.
  1103 void os::die() {
  1104   // _exit() on BsdThreads only kills current thread
  1105   ::abort();
  1108 // unused on bsd for now.
  1109 void os::set_error_file(const char *logfile) {}
  1112 // This method is a copy of JDK's sysGetLastErrorString
  1113 // from src/solaris/hpi/src/system_md.c
  1115 size_t os::lasterror(char *buf, size_t len) {
  1117   if (errno == 0)  return 0;
  1119   const char *s = ::strerror(errno);
  1120   size_t n = ::strlen(s);
  1121   if (n >= len) {
  1122     n = len - 1;
  1124   ::strncpy(buf, s, n);
  1125   buf[n] = '\0';
  1126   return n;
  1129 // Information of current thread in variety of formats
  1130 pid_t os::Bsd::gettid() {
  1131   int retval = -1;
  1133 #ifdef __APPLE__ //XNU kernel
  1134   // despite the fact mach port is actually not a thread id use it
  1135   // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
  1136   retval = ::pthread_mach_thread_np(::pthread_self());
  1137   guarantee(retval != 0, "just checking");
  1138   return retval;
  1140 #elif __FreeBSD__
  1141   retval = syscall(SYS_thr_self);
  1142 #elif __OpenBSD__
  1143   retval = syscall(SYS_getthrid);
  1144 #elif __NetBSD__
  1145   retval = (pid_t) syscall(SYS__lwp_self);
  1146 #endif
  1148   if (retval == -1) {
  1149     return getpid();
  1153 intx os::current_thread_id() {
  1154 #ifdef __APPLE__
  1155   return (intx)::pthread_mach_thread_np(::pthread_self());
  1156 #else
  1157   return (intx)::pthread_self();
  1158 #endif
  1161 int os::current_process_id() {
  1163   // Under the old bsd thread library, bsd gives each thread
  1164   // its own process id. Because of this each thread will return
  1165   // a different pid if this method were to return the result
  1166   // of getpid(2). Bsd provides no api that returns the pid
  1167   // of the launcher thread for the vm. This implementation
  1168   // returns a unique pid, the pid of the launcher thread
  1169   // that starts the vm 'process'.
  1171   // Under the NPTL, getpid() returns the same pid as the
  1172   // launcher thread rather than a unique pid per thread.
  1173   // Use gettid() if you want the old pre NPTL behaviour.
  1175   // if you are looking for the result of a call to getpid() that
  1176   // returns a unique pid for the calling thread, then look at the
  1177   // OSThread::thread_id() method in osThread_bsd.hpp file
  1179   return (int)(_initial_pid ? _initial_pid : getpid());
  1182 // DLL functions
  1184 #define JNI_LIB_PREFIX "lib"
  1185 #ifdef __APPLE__
  1186 #define JNI_LIB_SUFFIX ".dylib"
  1187 #else
  1188 #define JNI_LIB_SUFFIX ".so"
  1189 #endif
  1191 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
  1193 // This must be hard coded because it's the system's temporary
  1194 // directory not the java application's temp directory, ala java.io.tmpdir.
  1195 #ifdef __APPLE__
  1196 // macosx has a secure per-user temporary directory
  1197 char temp_path_storage[PATH_MAX];
  1198 const char* os::get_temp_directory() {
  1199   static char *temp_path = NULL;
  1200   if (temp_path == NULL) {
  1201     int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
  1202     if (pathSize == 0 || pathSize > PATH_MAX) {
  1203       strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
  1205     temp_path = temp_path_storage;
  1207   return temp_path;
  1209 #else /* __APPLE__ */
  1210 const char* os::get_temp_directory() { return "/tmp"; }
  1211 #endif /* __APPLE__ */
  1213 static bool file_exists(const char* filename) {
  1214   struct stat statbuf;
  1215   if (filename == NULL || strlen(filename) == 0) {
  1216     return false;
  1218   return os::stat(filename, &statbuf) == 0;
  1221 bool os::dll_build_name(char* buffer, size_t buflen,
  1222                         const char* pname, const char* fname) {
  1223   bool retval = false;
  1224   // Copied from libhpi
  1225   const size_t pnamelen = pname ? strlen(pname) : 0;
  1227   // Return error on buffer overflow.
  1228   if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
  1229     return retval;
  1232   if (pnamelen == 0) {
  1233     snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
  1234     retval = true;
  1235   } else if (strchr(pname, *os::path_separator()) != NULL) {
  1236     int n;
  1237     char** pelements = split_path(pname, &n);
  1238     if (pelements == NULL) {
  1239       return false;
  1241     for (int i = 0 ; i < n ; i++) {
  1242       // Really shouldn't be NULL, but check can't hurt
  1243       if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
  1244         continue; // skip the empty path values
  1246       snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
  1247           pelements[i], fname);
  1248       if (file_exists(buffer)) {
  1249         retval = true;
  1250         break;
  1253     // release the storage
  1254     for (int i = 0 ; i < n ; i++) {
  1255       if (pelements[i] != NULL) {
  1256         FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
  1259     if (pelements != NULL) {
  1260       FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
  1262   } else {
  1263     snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
  1264     retval = true;
  1266   return retval;
  1269 // check if addr is inside libjvm.so
  1270 bool os::address_is_in_vm(address addr) {
  1271   static address libjvm_base_addr;
  1272   Dl_info dlinfo;
  1274   if (libjvm_base_addr == NULL) {
  1275     if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
  1276       libjvm_base_addr = (address)dlinfo.dli_fbase;
  1278     assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
  1281   if (dladdr((void *)addr, &dlinfo) != 0) {
  1282     if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
  1285   return false;
  1289 #define MACH_MAXSYMLEN 256
  1291 bool os::dll_address_to_function_name(address addr, char *buf,
  1292                                       int buflen, int *offset) {
  1293   // buf is not optional, but offset is optional
  1294   assert(buf != NULL, "sanity check");
  1296   Dl_info dlinfo;
  1297   char localbuf[MACH_MAXSYMLEN];
  1299   if (dladdr((void*)addr, &dlinfo) != 0) {
  1300     // see if we have a matching symbol
  1301     if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
  1302       if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
  1303         jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
  1305       if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
  1306       return true;
  1308     // no matching symbol so try for just file info
  1309     if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
  1310       if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
  1311                           buf, buflen, offset, dlinfo.dli_fname)) {
  1312          return true;
  1316     // Handle non-dynamic manually:
  1317     if (dlinfo.dli_fbase != NULL &&
  1318         Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
  1319                         dlinfo.dli_fbase)) {
  1320       if (!Decoder::demangle(localbuf, buf, buflen)) {
  1321         jio_snprintf(buf, buflen, "%s", localbuf);
  1323       return true;
  1326   buf[0] = '\0';
  1327   if (offset != NULL) *offset = -1;
  1328   return false;
  1331 // ported from solaris version
  1332 bool os::dll_address_to_library_name(address addr, char* buf,
  1333                                      int buflen, int* offset) {
  1334   // buf is not optional, but offset is optional
  1335   assert(buf != NULL, "sanity check");
  1337   Dl_info dlinfo;
  1339   if (dladdr((void*)addr, &dlinfo) != 0) {
  1340     if (dlinfo.dli_fname != NULL) {
  1341       jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
  1343     if (dlinfo.dli_fbase != NULL && offset != NULL) {
  1344       *offset = addr - (address)dlinfo.dli_fbase;
  1346     return true;
  1349   buf[0] = '\0';
  1350   if (offset) *offset = -1;
  1351   return false;
  1354 // Loads .dll/.so and
  1355 // in case of error it checks if .dll/.so was built for the
  1356 // same architecture as Hotspot is running on
  1358 #ifdef __APPLE__
  1359 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
  1360   void * result= ::dlopen(filename, RTLD_LAZY);
  1361   if (result != NULL) {
  1362     // Successful loading
  1363     return result;
  1366   // Read system error message into ebuf
  1367   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1368   ebuf[ebuflen-1]='\0';
  1370   return NULL;
  1372 #else
  1373 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
  1375   void * result= ::dlopen(filename, RTLD_LAZY);
  1376   if (result != NULL) {
  1377     // Successful loading
  1378     return result;
  1381   Elf32_Ehdr elf_head;
  1383   // Read system error message into ebuf
  1384   // It may or may not be overwritten below
  1385   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1386   ebuf[ebuflen-1]='\0';
  1387   int diag_msg_max_length=ebuflen-strlen(ebuf);
  1388   char* diag_msg_buf=ebuf+strlen(ebuf);
  1390   if (diag_msg_max_length==0) {
  1391     // No more space in ebuf for additional diagnostics message
  1392     return NULL;
  1396   int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
  1398   if (file_descriptor < 0) {
  1399     // Can't open library, report dlerror() message
  1400     return NULL;
  1403   bool failed_to_read_elf_head=
  1404     (sizeof(elf_head)!=
  1405         (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
  1407   ::close(file_descriptor);
  1408   if (failed_to_read_elf_head) {
  1409     // file i/o error - report dlerror() msg
  1410     return NULL;
  1413   typedef struct {
  1414     Elf32_Half  code;         // Actual value as defined in elf.h
  1415     Elf32_Half  compat_class; // Compatibility of archs at VM's sense
  1416     char        elf_class;    // 32 or 64 bit
  1417     char        endianess;    // MSB or LSB
  1418     char*       name;         // String representation
  1419   } arch_t;
  1421   #ifndef EM_486
  1422   #define EM_486          6               /* Intel 80486 */
  1423   #endif
  1425   #ifndef EM_MIPS_RS3_LE
  1426   #define EM_MIPS_RS3_LE  10              /* MIPS */
  1427   #endif
  1429   #ifndef EM_PPC64
  1430   #define EM_PPC64        21              /* PowerPC64 */
  1431   #endif
  1433   #ifndef EM_S390
  1434   #define EM_S390         22              /* IBM System/390 */
  1435   #endif
  1437   #ifndef EM_IA_64
  1438   #define EM_IA_64        50              /* HP/Intel IA-64 */
  1439   #endif
  1441   #ifndef EM_X86_64
  1442   #define EM_X86_64       62              /* AMD x86-64 */
  1443   #endif
  1445   static const arch_t arch_array[]={
  1446     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1447     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1448     {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
  1449     {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
  1450     {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1451     {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1452     {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
  1453     {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
  1454     {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
  1455     {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
  1456     {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
  1457     {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
  1458     {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
  1459     {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
  1460     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
  1461     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
  1462   };
  1464   #if  (defined IA32)
  1465     static  Elf32_Half running_arch_code=EM_386;
  1466   #elif   (defined AMD64)
  1467     static  Elf32_Half running_arch_code=EM_X86_64;
  1468   #elif  (defined IA64)
  1469     static  Elf32_Half running_arch_code=EM_IA_64;
  1470   #elif  (defined __sparc) && (defined _LP64)
  1471     static  Elf32_Half running_arch_code=EM_SPARCV9;
  1472   #elif  (defined __sparc) && (!defined _LP64)
  1473     static  Elf32_Half running_arch_code=EM_SPARC;
  1474   #elif  (defined __powerpc64__)
  1475     static  Elf32_Half running_arch_code=EM_PPC64;
  1476   #elif  (defined __powerpc__)
  1477     static  Elf32_Half running_arch_code=EM_PPC;
  1478   #elif  (defined ARM)
  1479     static  Elf32_Half running_arch_code=EM_ARM;
  1480   #elif  (defined S390)
  1481     static  Elf32_Half running_arch_code=EM_S390;
  1482   #elif  (defined ALPHA)
  1483     static  Elf32_Half running_arch_code=EM_ALPHA;
  1484   #elif  (defined MIPSEL)
  1485     static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
  1486   #elif  (defined PARISC)
  1487     static  Elf32_Half running_arch_code=EM_PARISC;
  1488   #elif  (defined MIPS)
  1489     static  Elf32_Half running_arch_code=EM_MIPS;
  1490   #elif  (defined M68K)
  1491     static  Elf32_Half running_arch_code=EM_68K;
  1492   #else
  1493     #error Method os::dll_load requires that one of following is defined:\
  1494          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
  1495   #endif
  1497   // Identify compatability class for VM's architecture and library's architecture
  1498   // Obtain string descriptions for architectures
  1500   arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
  1501   int running_arch_index=-1;
  1503   for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
  1504     if (running_arch_code == arch_array[i].code) {
  1505       running_arch_index    = i;
  1507     if (lib_arch.code == arch_array[i].code) {
  1508       lib_arch.compat_class = arch_array[i].compat_class;
  1509       lib_arch.name         = arch_array[i].name;
  1513   assert(running_arch_index != -1,
  1514     "Didn't find running architecture code (running_arch_code) in arch_array");
  1515   if (running_arch_index == -1) {
  1516     // Even though running architecture detection failed
  1517     // we may still continue with reporting dlerror() message
  1518     return NULL;
  1521   if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
  1522     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
  1523     return NULL;
  1526 #ifndef S390
  1527   if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
  1528     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
  1529     return NULL;
  1531 #endif // !S390
  1533   if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
  1534     if ( lib_arch.name!=NULL ) {
  1535       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1536         " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
  1537         lib_arch.name, arch_array[running_arch_index].name);
  1538     } else {
  1539       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1540       " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
  1541         lib_arch.code,
  1542         arch_array[running_arch_index].name);
  1546   return NULL;
  1548 #endif /* !__APPLE__ */
  1550 // XXX: Do we need a lock around this as per Linux?
  1551 void* os::dll_lookup(void* handle, const char* name) {
  1552   return dlsym(handle, name);
  1556 static bool _print_ascii_file(const char* filename, outputStream* st) {
  1557   int fd = ::open(filename, O_RDONLY);
  1558   if (fd == -1) {
  1559      return false;
  1562   char buf[32];
  1563   int bytes;
  1564   while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
  1565     st->print_raw(buf, bytes);
  1568   ::close(fd);
  1570   return true;
  1573 void os::print_dll_info(outputStream *st) {
  1574   st->print_cr("Dynamic libraries:");
  1575 #ifdef RTLD_DI_LINKMAP
  1576   Dl_info dli;
  1577   void *handle;
  1578   Link_map *map;
  1579   Link_map *p;
  1581   if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
  1582       dli.dli_fname == NULL) {
  1583     st->print_cr("Error: Cannot print dynamic libraries.");
  1584     return;
  1586   handle = dlopen(dli.dli_fname, RTLD_LAZY);
  1587   if (handle == NULL) {
  1588     st->print_cr("Error: Cannot print dynamic libraries.");
  1589     return;
  1591   dlinfo(handle, RTLD_DI_LINKMAP, &map);
  1592   if (map == NULL) {
  1593     st->print_cr("Error: Cannot print dynamic libraries.");
  1594     return;
  1597   while (map->l_prev != NULL)
  1598     map = map->l_prev;
  1600   while (map != NULL) {
  1601     st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
  1602     map = map->l_next;
  1605   dlclose(handle);
  1606 #elif defined(__APPLE__)
  1607   uint32_t count;
  1608   uint32_t i;
  1610   count = _dyld_image_count();
  1611   for (i = 1; i < count; i++) {
  1612     const char *name = _dyld_get_image_name(i);
  1613     intptr_t slide = _dyld_get_image_vmaddr_slide(i);
  1614     st->print_cr(PTR_FORMAT " \t%s", slide, name);
  1616 #else
  1617   st->print_cr("Error: Cannot print dynamic libraries.");
  1618 #endif
  1621 void os::print_os_info_brief(outputStream* st) {
  1622   st->print("Bsd");
  1624   os::Posix::print_uname_info(st);
  1627 void os::print_os_info(outputStream* st) {
  1628   st->print("OS:");
  1629   st->print("Bsd");
  1631   os::Posix::print_uname_info(st);
  1633   os::Posix::print_rlimit_info(st);
  1635   os::Posix::print_load_average(st);
  1638 void os::pd_print_cpu_info(outputStream* st) {
  1639   // Nothing to do for now.
  1642 void os::print_memory_info(outputStream* st) {
  1644   st->print("Memory:");
  1645   st->print(" %dk page", os::vm_page_size()>>10);
  1647   st->print(", physical " UINT64_FORMAT "k",
  1648             os::physical_memory() >> 10);
  1649   st->print("(" UINT64_FORMAT "k free)",
  1650             os::available_memory() >> 10);
  1651   st->cr();
  1653   // meminfo
  1654   st->print("\n/proc/meminfo:\n");
  1655   _print_ascii_file("/proc/meminfo", st);
  1656   st->cr();
  1659 // Taken from /usr/include/bits/siginfo.h  Supposed to be architecture specific
  1660 // but they're the same for all the bsd arch that we support
  1661 // and they're the same for solaris but there's no common place to put this.
  1662 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
  1663                           "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
  1664                           "ILL_COPROC", "ILL_BADSTK" };
  1666 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
  1667                           "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
  1668                           "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
  1670 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
  1672 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
  1674 void os::print_siginfo(outputStream* st, void* siginfo) {
  1675   st->print("siginfo:");
  1677   const int buflen = 100;
  1678   char buf[buflen];
  1679   siginfo_t *si = (siginfo_t*)siginfo;
  1680   st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
  1681   if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
  1682     st->print("si_errno=%s", buf);
  1683   } else {
  1684     st->print("si_errno=%d", si->si_errno);
  1686   const int c = si->si_code;
  1687   assert(c > 0, "unexpected si_code");
  1688   switch (si->si_signo) {
  1689   case SIGILL:
  1690     st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
  1691     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1692     break;
  1693   case SIGFPE:
  1694     st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
  1695     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1696     break;
  1697   case SIGSEGV:
  1698     st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
  1699     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1700     break;
  1701   case SIGBUS:
  1702     st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
  1703     st->print(", si_addr=" PTR_FORMAT, si->si_addr);
  1704     break;
  1705   default:
  1706     st->print(", si_code=%d", si->si_code);
  1707     // no si_addr
  1710   if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
  1711       UseSharedSpaces) {
  1712     FileMapInfo* mapinfo = FileMapInfo::current_info();
  1713     if (mapinfo->is_in_shared_space(si->si_addr)) {
  1714       st->print("\n\nError accessing class data sharing archive."   \
  1715                 " Mapped file inaccessible during execution, "      \
  1716                 " possible disk/network problem.");
  1719   st->cr();
  1723 static void print_signal_handler(outputStream* st, int sig,
  1724                                  char* buf, size_t buflen);
  1726 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
  1727   st->print_cr("Signal Handlers:");
  1728   print_signal_handler(st, SIGSEGV, buf, buflen);
  1729   print_signal_handler(st, SIGBUS , buf, buflen);
  1730   print_signal_handler(st, SIGFPE , buf, buflen);
  1731   print_signal_handler(st, SIGPIPE, buf, buflen);
  1732   print_signal_handler(st, SIGXFSZ, buf, buflen);
  1733   print_signal_handler(st, SIGILL , buf, buflen);
  1734   print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
  1735   print_signal_handler(st, SR_signum, buf, buflen);
  1736   print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
  1737   print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
  1738   print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
  1739   print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
  1742 static char saved_jvm_path[MAXPATHLEN] = {0};
  1744 // Find the full path to the current module, libjvm
  1745 void os::jvm_path(char *buf, jint buflen) {
  1746   // Error checking.
  1747   if (buflen < MAXPATHLEN) {
  1748     assert(false, "must use a large-enough buffer");
  1749     buf[0] = '\0';
  1750     return;
  1752   // Lazy resolve the path to current module.
  1753   if (saved_jvm_path[0] != 0) {
  1754     strcpy(buf, saved_jvm_path);
  1755     return;
  1758   char dli_fname[MAXPATHLEN];
  1759   bool ret = dll_address_to_library_name(
  1760                 CAST_FROM_FN_PTR(address, os::jvm_path),
  1761                 dli_fname, sizeof(dli_fname), NULL);
  1762   assert(ret, "cannot locate libjvm");
  1763   char *rp = NULL;
  1764   if (ret && dli_fname[0] != '\0') {
  1765     rp = realpath(dli_fname, buf);
  1767   if (rp == NULL)
  1768     return;
  1770   if (Arguments::created_by_gamma_launcher()) {
  1771     // Support for the gamma launcher.  Typical value for buf is
  1772     // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm".  If "/jre/lib/" appears at
  1773     // the right place in the string, then assume we are installed in a JDK and
  1774     // we're done.  Otherwise, check for a JAVA_HOME environment variable and
  1775     // construct a path to the JVM being overridden.
  1777     const char *p = buf + strlen(buf) - 1;
  1778     for (int count = 0; p > buf && count < 5; ++count) {
  1779       for (--p; p > buf && *p != '/'; --p)
  1780         /* empty */ ;
  1783     if (strncmp(p, "/jre/lib/", 9) != 0) {
  1784       // Look for JAVA_HOME in the environment.
  1785       char* java_home_var = ::getenv("JAVA_HOME");
  1786       if (java_home_var != NULL && java_home_var[0] != 0) {
  1787         char* jrelib_p;
  1788         int len;
  1790         // Check the current module name "libjvm"
  1791         p = strrchr(buf, '/');
  1792         assert(strstr(p, "/libjvm") == p, "invalid library name");
  1794         rp = realpath(java_home_var, buf);
  1795         if (rp == NULL)
  1796           return;
  1798         // determine if this is a legacy image or modules image
  1799         // modules image doesn't have "jre" subdirectory
  1800         len = strlen(buf);
  1801         jrelib_p = buf + len;
  1803         // Add the appropriate library subdir
  1804         snprintf(jrelib_p, buflen-len, "/jre/lib");
  1805         if (0 != access(buf, F_OK)) {
  1806           snprintf(jrelib_p, buflen-len, "/lib");
  1809         // Add the appropriate client or server subdir
  1810         len = strlen(buf);
  1811         jrelib_p = buf + len;
  1812         snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
  1813         if (0 != access(buf, F_OK)) {
  1814           snprintf(jrelib_p, buflen-len, "");
  1817         // If the path exists within JAVA_HOME, add the JVM library name
  1818         // to complete the path to JVM being overridden.  Otherwise fallback
  1819         // to the path to the current library.
  1820         if (0 == access(buf, F_OK)) {
  1821           // Use current module name "libjvm"
  1822           len = strlen(buf);
  1823           snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
  1824         } else {
  1825           // Fall back to path of current library
  1826           rp = realpath(dli_fname, buf);
  1827           if (rp == NULL)
  1828             return;
  1834   strcpy(saved_jvm_path, buf);
  1837 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
  1838   // no prefix required, not even "_"
  1841 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
  1842   // no suffix required
  1845 ////////////////////////////////////////////////////////////////////////////////
  1846 // sun.misc.Signal support
  1848 static volatile jint sigint_count = 0;
  1850 static void
  1851 UserHandler(int sig, void *siginfo, void *context) {
  1852   // 4511530 - sem_post is serialized and handled by the manager thread. When
  1853   // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
  1854   // don't want to flood the manager thread with sem_post requests.
  1855   if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
  1856       return;
  1858   // Ctrl-C is pressed during error reporting, likely because the error
  1859   // handler fails to abort. Let VM die immediately.
  1860   if (sig == SIGINT && is_error_reported()) {
  1861      os::die();
  1864   os::signal_notify(sig);
  1867 void* os::user_handler() {
  1868   return CAST_FROM_FN_PTR(void*, UserHandler);
  1871 extern "C" {
  1872   typedef void (*sa_handler_t)(int);
  1873   typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
  1876 void* os::signal(int signal_number, void* handler) {
  1877   struct sigaction sigAct, oldSigAct;
  1879   sigfillset(&(sigAct.sa_mask));
  1880   sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
  1881   sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
  1883   if (sigaction(signal_number, &sigAct, &oldSigAct)) {
  1884     // -1 means registration failed
  1885     return (void *)-1;
  1888   return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
  1891 void os::signal_raise(int signal_number) {
  1892   ::raise(signal_number);
  1895 /*
  1896  * The following code is moved from os.cpp for making this
  1897  * code platform specific, which it is by its very nature.
  1898  */
  1900 // Will be modified when max signal is changed to be dynamic
  1901 int os::sigexitnum_pd() {
  1902   return NSIG;
  1905 // a counter for each possible signal value
  1906 static volatile jint pending_signals[NSIG+1] = { 0 };
  1908 // Bsd(POSIX) specific hand shaking semaphore.
  1909 #ifdef __APPLE__
  1910 typedef semaphore_t os_semaphore_t;
  1911 #define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
  1912 #define SEM_WAIT(sem)           semaphore_wait(sem)
  1913 #define SEM_POST(sem)           semaphore_signal(sem)
  1914 #define SEM_DESTROY(sem)        semaphore_destroy(mach_task_self(), sem)
  1915 #else
  1916 typedef sem_t os_semaphore_t;
  1917 #define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
  1918 #define SEM_WAIT(sem)           sem_wait(&sem)
  1919 #define SEM_POST(sem)           sem_post(&sem)
  1920 #define SEM_DESTROY(sem)        sem_destroy(&sem)
  1921 #endif
  1923 class Semaphore : public StackObj {
  1924   public:
  1925     Semaphore();
  1926     ~Semaphore();
  1927     void signal();
  1928     void wait();
  1929     bool trywait();
  1930     bool timedwait(unsigned int sec, int nsec);
  1931   private:
  1932     jlong currenttime() const;
  1933     os_semaphore_t _semaphore;
  1934 };
  1936 Semaphore::Semaphore() : _semaphore(0) {
  1937   SEM_INIT(_semaphore, 0);
  1940 Semaphore::~Semaphore() {
  1941   SEM_DESTROY(_semaphore);
  1944 void Semaphore::signal() {
  1945   SEM_POST(_semaphore);
  1948 void Semaphore::wait() {
  1949   SEM_WAIT(_semaphore);
  1952 jlong Semaphore::currenttime() const {
  1953     struct timeval tv;
  1954     gettimeofday(&tv, NULL);
  1955     return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
  1958 #ifdef __APPLE__
  1959 bool Semaphore::trywait() {
  1960   return timedwait(0, 0);
  1963 bool Semaphore::timedwait(unsigned int sec, int nsec) {
  1964   kern_return_t kr = KERN_ABORTED;
  1965   mach_timespec_t waitspec;
  1966   waitspec.tv_sec = sec;
  1967   waitspec.tv_nsec = nsec;
  1969   jlong starttime = currenttime();
  1971   kr = semaphore_timedwait(_semaphore, waitspec);
  1972   while (kr == KERN_ABORTED) {
  1973     jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
  1975     jlong current = currenttime();
  1976     jlong passedtime = current - starttime;
  1978     if (passedtime >= totalwait) {
  1979       waitspec.tv_sec = 0;
  1980       waitspec.tv_nsec = 0;
  1981     } else {
  1982       jlong waittime = totalwait - (current - starttime);
  1983       waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
  1984       waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
  1987     kr = semaphore_timedwait(_semaphore, waitspec);
  1990   return kr == KERN_SUCCESS;
  1993 #else
  1995 bool Semaphore::trywait() {
  1996   return sem_trywait(&_semaphore) == 0;
  1999 bool Semaphore::timedwait(unsigned int sec, int nsec) {
  2000   struct timespec ts;
  2001   unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
  2003   while (1) {
  2004     int result = sem_timedwait(&_semaphore, &ts);
  2005     if (result == 0) {
  2006       return true;
  2007     } else if (errno == EINTR) {
  2008       continue;
  2009     } else if (errno == ETIMEDOUT) {
  2010       return false;
  2011     } else {
  2012       return false;
  2017 #endif // __APPLE__
  2019 static os_semaphore_t sig_sem;
  2020 static Semaphore sr_semaphore;
  2022 void os::signal_init_pd() {
  2023   // Initialize signal structures
  2024   ::memset((void*)pending_signals, 0, sizeof(pending_signals));
  2026   // Initialize signal semaphore
  2027   ::SEM_INIT(sig_sem, 0);
  2030 void os::signal_notify(int sig) {
  2031   Atomic::inc(&pending_signals[sig]);
  2032   ::SEM_POST(sig_sem);
  2035 static int check_pending_signals(bool wait) {
  2036   Atomic::store(0, &sigint_count);
  2037   for (;;) {
  2038     for (int i = 0; i < NSIG + 1; i++) {
  2039       jint n = pending_signals[i];
  2040       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
  2041         return i;
  2044     if (!wait) {
  2045       return -1;
  2047     JavaThread *thread = JavaThread::current();
  2048     ThreadBlockInVM tbivm(thread);
  2050     bool threadIsSuspended;
  2051     do {
  2052       thread->set_suspend_equivalent();
  2053       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  2054       ::SEM_WAIT(sig_sem);
  2056       // were we externally suspended while we were waiting?
  2057       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
  2058       if (threadIsSuspended) {
  2059         //
  2060         // The semaphore has been incremented, but while we were waiting
  2061         // another thread suspended us. We don't want to continue running
  2062         // while suspended because that would surprise the thread that
  2063         // suspended us.
  2064         //
  2065         ::SEM_POST(sig_sem);
  2067         thread->java_suspend_self();
  2069     } while (threadIsSuspended);
  2073 int os::signal_lookup() {
  2074   return check_pending_signals(false);
  2077 int os::signal_wait() {
  2078   return check_pending_signals(true);
  2081 ////////////////////////////////////////////////////////////////////////////////
  2082 // Virtual Memory
  2084 int os::vm_page_size() {
  2085   // Seems redundant as all get out
  2086   assert(os::Bsd::page_size() != -1, "must call os::init");
  2087   return os::Bsd::page_size();
  2090 // Solaris allocates memory by pages.
  2091 int os::vm_allocation_granularity() {
  2092   assert(os::Bsd::page_size() != -1, "must call os::init");
  2093   return os::Bsd::page_size();
  2096 // Rationale behind this function:
  2097 //  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
  2098 //  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
  2099 //  samples for JITted code. Here we create private executable mapping over the code cache
  2100 //  and then we can use standard (well, almost, as mapping can change) way to provide
  2101 //  info for the reporting script by storing timestamp and location of symbol
  2102 void bsd_wrap_code(char* base, size_t size) {
  2103   static volatile jint cnt = 0;
  2105   if (!UseOprofile) {
  2106     return;
  2109   char buf[PATH_MAX + 1];
  2110   int num = Atomic::add(1, &cnt);
  2112   snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
  2113            os::get_temp_directory(), os::current_process_id(), num);
  2114   unlink(buf);
  2116   int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
  2118   if (fd != -1) {
  2119     off_t rv = ::lseek(fd, size-2, SEEK_SET);
  2120     if (rv != (off_t)-1) {
  2121       if (::write(fd, "", 1) == 1) {
  2122         mmap(base, size,
  2123              PROT_READ|PROT_WRITE|PROT_EXEC,
  2124              MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
  2127     ::close(fd);
  2128     unlink(buf);
  2132 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
  2133                                     int err) {
  2134   warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
  2135           ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
  2136           strerror(err), err);
  2139 // NOTE: Bsd kernel does not really reserve the pages for us.
  2140 //       All it does is to check if there are enough free pages
  2141 //       left at the time of mmap(). This could be a potential
  2142 //       problem.
  2143 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
  2144   int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
  2145 #ifdef __OpenBSD__
  2146   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  2147   if (::mprotect(addr, size, prot) == 0) {
  2148     return true;
  2150 #else
  2151   uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
  2152                                    MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
  2153   if (res != (uintptr_t) MAP_FAILED) {
  2154     return true;
  2156 #endif
  2158   // Warn about any commit errors we see in non-product builds just
  2159   // in case mmap() doesn't work as described on the man page.
  2160   NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
  2162   return false;
  2165 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
  2166                        bool exec) {
  2167   // alignment_hint is ignored on this OS
  2168   return pd_commit_memory(addr, size, exec);
  2171 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
  2172                                   const char* mesg) {
  2173   assert(mesg != NULL, "mesg must be specified");
  2174   if (!pd_commit_memory(addr, size, exec)) {
  2175     // add extra info in product mode for vm_exit_out_of_memory():
  2176     PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
  2177     vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
  2181 void os::pd_commit_memory_or_exit(char* addr, size_t size,
  2182                                   size_t alignment_hint, bool exec,
  2183                                   const char* mesg) {
  2184   // alignment_hint is ignored on this OS
  2185   pd_commit_memory_or_exit(addr, size, exec, mesg);
  2188 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2191 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2192   ::madvise(addr, bytes, MADV_DONTNEED);
  2195 void os::numa_make_global(char *addr, size_t bytes) {
  2198 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
  2201 bool os::numa_topology_changed()   { return false; }
  2203 size_t os::numa_get_groups_num() {
  2204   return 1;
  2207 int os::numa_get_group_id() {
  2208   return 0;
  2211 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
  2212   if (size > 0) {
  2213     ids[0] = 0;
  2214     return 1;
  2216   return 0;
  2219 bool os::get_page_info(char *start, page_info* info) {
  2220   return false;
  2223 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
  2224   return end;
  2228 bool os::pd_uncommit_memory(char* addr, size_t size) {
  2229 #ifdef __OpenBSD__
  2230   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  2231   return ::mprotect(addr, size, PROT_NONE) == 0;
  2232 #else
  2233   uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
  2234                 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
  2235   return res  != (uintptr_t) MAP_FAILED;
  2236 #endif
  2239 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
  2240   return os::commit_memory(addr, size, !ExecMem);
  2243 // If this is a growable mapping, remove the guard pages entirely by
  2244 // munmap()ping them.  If not, just call uncommit_memory().
  2245 bool os::remove_stack_guard_pages(char* addr, size_t size) {
  2246   return os::uncommit_memory(addr, size);
  2249 static address _highest_vm_reserved_address = NULL;
  2251 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
  2252 // at 'requested_addr'. If there are existing memory mappings at the same
  2253 // location, however, they will be overwritten. If 'fixed' is false,
  2254 // 'requested_addr' is only treated as a hint, the return value may or
  2255 // may not start from the requested address. Unlike Bsd mmap(), this
  2256 // function returns NULL to indicate failure.
  2257 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
  2258   char * addr;
  2259   int flags;
  2261   flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
  2262   if (fixed) {
  2263     assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
  2264     flags |= MAP_FIXED;
  2267   // Map reserved/uncommitted pages PROT_NONE so we fail early if we
  2268   // touch an uncommitted page. Otherwise, the read/write might
  2269   // succeed if we have enough swap space to back the physical page.
  2270   addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
  2271                        flags, -1, 0);
  2273   if (addr != MAP_FAILED) {
  2274     // anon_mmap() should only get called during VM initialization,
  2275     // don't need lock (actually we can skip locking even it can be called
  2276     // from multiple threads, because _highest_vm_reserved_address is just a
  2277     // hint about the upper limit of non-stack memory regions.)
  2278     if ((address)addr + bytes > _highest_vm_reserved_address) {
  2279       _highest_vm_reserved_address = (address)addr + bytes;
  2283   return addr == MAP_FAILED ? NULL : addr;
  2286 // Don't update _highest_vm_reserved_address, because there might be memory
  2287 // regions above addr + size. If so, releasing a memory region only creates
  2288 // a hole in the address space, it doesn't help prevent heap-stack collision.
  2289 //
  2290 static int anon_munmap(char * addr, size_t size) {
  2291   return ::munmap(addr, size) == 0;
  2294 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
  2295                          size_t alignment_hint) {
  2296   return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
  2299 bool os::pd_release_memory(char* addr, size_t size) {
  2300   return anon_munmap(addr, size);
  2303 static bool bsd_mprotect(char* addr, size_t size, int prot) {
  2304   // Bsd wants the mprotect address argument to be page aligned.
  2305   char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
  2307   // According to SUSv3, mprotect() should only be used with mappings
  2308   // established by mmap(), and mmap() always maps whole pages. Unaligned
  2309   // 'addr' likely indicates problem in the VM (e.g. trying to change
  2310   // protection of malloc'ed or statically allocated memory). Check the
  2311   // caller if you hit this assert.
  2312   assert(addr == bottom, "sanity check");
  2314   size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
  2315   return ::mprotect(bottom, size, prot) == 0;
  2318 // Set protections specified
  2319 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
  2320                         bool is_committed) {
  2321   unsigned int p = 0;
  2322   switch (prot) {
  2323   case MEM_PROT_NONE: p = PROT_NONE; break;
  2324   case MEM_PROT_READ: p = PROT_READ; break;
  2325   case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
  2326   case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
  2327   default:
  2328     ShouldNotReachHere();
  2330   // is_committed is unused.
  2331   return bsd_mprotect(addr, bytes, p);
  2334 bool os::guard_memory(char* addr, size_t size) {
  2335   return bsd_mprotect(addr, size, PROT_NONE);
  2338 bool os::unguard_memory(char* addr, size_t size) {
  2339   return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
  2342 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
  2343   return false;
  2346 // Large page support
  2348 static size_t _large_page_size = 0;
  2350 void os::large_page_init() {
  2354 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
  2355   fatal("This code is not used or maintained.");
  2357   // "exec" is passed in but not used.  Creating the shared image for
  2358   // the code cache doesn't have an SHM_X executable permission to check.
  2359   assert(UseLargePages && UseSHM, "only for SHM large pages");
  2361   key_t key = IPC_PRIVATE;
  2362   char *addr;
  2364   bool warn_on_failure = UseLargePages &&
  2365                         (!FLAG_IS_DEFAULT(UseLargePages) ||
  2366                          !FLAG_IS_DEFAULT(LargePageSizeInBytes)
  2367                         );
  2368   char msg[128];
  2370   // Create a large shared memory region to attach to based on size.
  2371   // Currently, size is the total size of the heap
  2372   int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
  2373   if (shmid == -1) {
  2374      // Possible reasons for shmget failure:
  2375      // 1. shmmax is too small for Java heap.
  2376      //    > check shmmax value: cat /proc/sys/kernel/shmmax
  2377      //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
  2378      // 2. not enough large page memory.
  2379      //    > check available large pages: cat /proc/meminfo
  2380      //    > increase amount of large pages:
  2381      //          echo new_value > /proc/sys/vm/nr_hugepages
  2382      //      Note 1: different Bsd may use different name for this property,
  2383      //            e.g. on Redhat AS-3 it is "hugetlb_pool".
  2384      //      Note 2: it's possible there's enough physical memory available but
  2385      //            they are so fragmented after a long run that they can't
  2386      //            coalesce into large pages. Try to reserve large pages when
  2387      //            the system is still "fresh".
  2388      if (warn_on_failure) {
  2389        jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
  2390        warning(msg);
  2392      return NULL;
  2395   // attach to the region
  2396   addr = (char*)shmat(shmid, req_addr, 0);
  2397   int err = errno;
  2399   // Remove shmid. If shmat() is successful, the actual shared memory segment
  2400   // will be deleted when it's detached by shmdt() or when the process
  2401   // terminates. If shmat() is not successful this will remove the shared
  2402   // segment immediately.
  2403   shmctl(shmid, IPC_RMID, NULL);
  2405   if ((intptr_t)addr == -1) {
  2406      if (warn_on_failure) {
  2407        jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
  2408        warning(msg);
  2410      return NULL;
  2413   // The memory is committed
  2414   MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
  2416   return addr;
  2419 bool os::release_memory_special(char* base, size_t bytes) {
  2420   MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
  2421   // detaching the SHM segment will also delete it, see reserve_memory_special()
  2422   int rslt = shmdt(base);
  2423   if (rslt == 0) {
  2424     tkr.record((address)base, bytes);
  2425     return true;
  2426   } else {
  2427     tkr.discard();
  2428     return false;
  2433 size_t os::large_page_size() {
  2434   return _large_page_size;
  2437 // HugeTLBFS allows application to commit large page memory on demand;
  2438 // with SysV SHM the entire memory region must be allocated as shared
  2439 // memory.
  2440 bool os::can_commit_large_page_memory() {
  2441   return UseHugeTLBFS;
  2444 bool os::can_execute_large_page_memory() {
  2445   return UseHugeTLBFS;
  2448 // Reserve memory at an arbitrary address, only if that area is
  2449 // available (and not reserved for something else).
  2451 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
  2452   const int max_tries = 10;
  2453   char* base[max_tries];
  2454   size_t size[max_tries];
  2455   const size_t gap = 0x000000;
  2457   // Assert only that the size is a multiple of the page size, since
  2458   // that's all that mmap requires, and since that's all we really know
  2459   // about at this low abstraction level.  If we need higher alignment,
  2460   // we can either pass an alignment to this method or verify alignment
  2461   // in one of the methods further up the call chain.  See bug 5044738.
  2462   assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
  2464   // Repeatedly allocate blocks until the block is allocated at the
  2465   // right spot. Give up after max_tries. Note that reserve_memory() will
  2466   // automatically update _highest_vm_reserved_address if the call is
  2467   // successful. The variable tracks the highest memory address every reserved
  2468   // by JVM. It is used to detect heap-stack collision if running with
  2469   // fixed-stack BsdThreads. Because here we may attempt to reserve more
  2470   // space than needed, it could confuse the collision detecting code. To
  2471   // solve the problem, save current _highest_vm_reserved_address and
  2472   // calculate the correct value before return.
  2473   address old_highest = _highest_vm_reserved_address;
  2475   // Bsd mmap allows caller to pass an address as hint; give it a try first,
  2476   // if kernel honors the hint then we can return immediately.
  2477   char * addr = anon_mmap(requested_addr, bytes, false);
  2478   if (addr == requested_addr) {
  2479      return requested_addr;
  2482   if (addr != NULL) {
  2483      // mmap() is successful but it fails to reserve at the requested address
  2484      anon_munmap(addr, bytes);
  2487   int i;
  2488   for (i = 0; i < max_tries; ++i) {
  2489     base[i] = reserve_memory(bytes);
  2491     if (base[i] != NULL) {
  2492       // Is this the block we wanted?
  2493       if (base[i] == requested_addr) {
  2494         size[i] = bytes;
  2495         break;
  2498       // Does this overlap the block we wanted? Give back the overlapped
  2499       // parts and try again.
  2501       size_t top_overlap = requested_addr + (bytes + gap) - base[i];
  2502       if (top_overlap >= 0 && top_overlap < bytes) {
  2503         unmap_memory(base[i], top_overlap);
  2504         base[i] += top_overlap;
  2505         size[i] = bytes - top_overlap;
  2506       } else {
  2507         size_t bottom_overlap = base[i] + bytes - requested_addr;
  2508         if (bottom_overlap >= 0 && bottom_overlap < bytes) {
  2509           unmap_memory(requested_addr, bottom_overlap);
  2510           size[i] = bytes - bottom_overlap;
  2511         } else {
  2512           size[i] = bytes;
  2518   // Give back the unused reserved pieces.
  2520   for (int j = 0; j < i; ++j) {
  2521     if (base[j] != NULL) {
  2522       unmap_memory(base[j], size[j]);
  2526   if (i < max_tries) {
  2527     _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
  2528     return requested_addr;
  2529   } else {
  2530     _highest_vm_reserved_address = old_highest;
  2531     return NULL;
  2535 size_t os::read(int fd, void *buf, unsigned int nBytes) {
  2536   RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
  2539 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
  2540 // Solaris uses poll(), bsd uses park().
  2541 // Poll() is likely a better choice, assuming that Thread.interrupt()
  2542 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
  2543 // SIGSEGV, see 4355769.
  2545 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
  2546   assert(thread == Thread::current(),  "thread consistency check");
  2548   ParkEvent * const slp = thread->_SleepEvent ;
  2549   slp->reset() ;
  2550   OrderAccess::fence() ;
  2552   if (interruptible) {
  2553     jlong prevtime = javaTimeNanos();
  2555     for (;;) {
  2556       if (os::is_interrupted(thread, true)) {
  2557         return OS_INTRPT;
  2560       jlong newtime = javaTimeNanos();
  2562       if (newtime - prevtime < 0) {
  2563         // time moving backwards, should only happen if no monotonic clock
  2564         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2565         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2566       } else {
  2567         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2570       if(millis <= 0) {
  2571         return OS_OK;
  2574       prevtime = newtime;
  2577         assert(thread->is_Java_thread(), "sanity check");
  2578         JavaThread *jt = (JavaThread *) thread;
  2579         ThreadBlockInVM tbivm(jt);
  2580         OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
  2582         jt->set_suspend_equivalent();
  2583         // cleared by handle_special_suspend_equivalent_condition() or
  2584         // java_suspend_self() via check_and_wait_while_suspended()
  2586         slp->park(millis);
  2588         // were we externally suspended while we were waiting?
  2589         jt->check_and_wait_while_suspended();
  2592   } else {
  2593     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  2594     jlong prevtime = javaTimeNanos();
  2596     for (;;) {
  2597       // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
  2598       // the 1st iteration ...
  2599       jlong newtime = javaTimeNanos();
  2601       if (newtime - prevtime < 0) {
  2602         // time moving backwards, should only happen if no monotonic clock
  2603         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2604         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2605       } else {
  2606         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2609       if(millis <= 0) break ;
  2611       prevtime = newtime;
  2612       slp->park(millis);
  2614     return OS_OK ;
  2618 int os::naked_sleep() {
  2619   // %% make the sleep time an integer flag. for now use 1 millisec.
  2620   return os::sleep(Thread::current(), 1, false);
  2623 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
  2624 void os::infinite_sleep() {
  2625   while (true) {    // sleep forever ...
  2626     ::sleep(100);   // ... 100 seconds at a time
  2630 // Used to convert frequent JVM_Yield() to nops
  2631 bool os::dont_yield() {
  2632   return DontYieldALot;
  2635 void os::yield() {
  2636   sched_yield();
  2639 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
  2641 void os::yield_all(int attempts) {
  2642   // Yields to all threads, including threads with lower priorities
  2643   // Threads on Bsd are all with same priority. The Solaris style
  2644   // os::yield_all() with nanosleep(1ms) is not necessary.
  2645   sched_yield();
  2648 // Called from the tight loops to possibly influence time-sharing heuristics
  2649 void os::loop_breaker(int attempts) {
  2650   os::yield_all(attempts);
  2653 ////////////////////////////////////////////////////////////////////////////////
  2654 // thread priority support
  2656 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
  2657 // only supports dynamic priority, static priority must be zero. For real-time
  2658 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
  2659 // However, for large multi-threaded applications, SCHED_RR is not only slower
  2660 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
  2661 // of 5 runs - Sep 2005).
  2662 //
  2663 // The following code actually changes the niceness of kernel-thread/LWP. It
  2664 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
  2665 // not the entire user process, and user level threads are 1:1 mapped to kernel
  2666 // threads. It has always been the case, but could change in the future. For
  2667 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
  2668 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
  2670 #if !defined(__APPLE__)
  2671 int os::java_to_os_priority[CriticalPriority + 1] = {
  2672   19,              // 0 Entry should never be used
  2674    0,              // 1 MinPriority
  2675    3,              // 2
  2676    6,              // 3
  2678   10,              // 4
  2679   15,              // 5 NormPriority
  2680   18,              // 6
  2682   21,              // 7
  2683   25,              // 8
  2684   28,              // 9 NearMaxPriority
  2686   31,              // 10 MaxPriority
  2688   31               // 11 CriticalPriority
  2689 };
  2690 #else
  2691 /* Using Mach high-level priority assignments */
  2692 int os::java_to_os_priority[CriticalPriority + 1] = {
  2693    0,              // 0 Entry should never be used (MINPRI_USER)
  2695   27,              // 1 MinPriority
  2696   28,              // 2
  2697   29,              // 3
  2699   30,              // 4
  2700   31,              // 5 NormPriority (BASEPRI_DEFAULT)
  2701   32,              // 6
  2703   33,              // 7
  2704   34,              // 8
  2705   35,              // 9 NearMaxPriority
  2707   36,              // 10 MaxPriority
  2709   36               // 11 CriticalPriority
  2710 };
  2711 #endif
  2713 static int prio_init() {
  2714   if (ThreadPriorityPolicy == 1) {
  2715     // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
  2716     // if effective uid is not root. Perhaps, a more elegant way of doing
  2717     // this is to test CAP_SYS_NICE capability, but that will require libcap.so
  2718     if (geteuid() != 0) {
  2719       if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
  2720         warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
  2722       ThreadPriorityPolicy = 0;
  2725   if (UseCriticalJavaThreadPriority) {
  2726     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
  2728   return 0;
  2731 OSReturn os::set_native_priority(Thread* thread, int newpri) {
  2732   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
  2734 #ifdef __OpenBSD__
  2735   // OpenBSD pthread_setprio starves low priority threads
  2736   return OS_OK;
  2737 #elif defined(__FreeBSD__)
  2738   int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
  2739 #elif defined(__APPLE__) || defined(__NetBSD__)
  2740   struct sched_param sp;
  2741   int policy;
  2742   pthread_t self = pthread_self();
  2744   if (pthread_getschedparam(self, &policy, &sp) != 0)
  2745     return OS_ERR;
  2747   sp.sched_priority = newpri;
  2748   if (pthread_setschedparam(self, policy, &sp) != 0)
  2749     return OS_ERR;
  2751   return OS_OK;
  2752 #else
  2753   int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
  2754   return (ret == 0) ? OS_OK : OS_ERR;
  2755 #endif
  2758 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
  2759   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
  2760     *priority_ptr = java_to_os_priority[NormPriority];
  2761     return OS_OK;
  2764   errno = 0;
  2765 #if defined(__OpenBSD__) || defined(__FreeBSD__)
  2766   *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
  2767 #elif defined(__APPLE__) || defined(__NetBSD__)
  2768   int policy;
  2769   struct sched_param sp;
  2771   pthread_getschedparam(pthread_self(), &policy, &sp);
  2772   *priority_ptr = sp.sched_priority;
  2773 #else
  2774   *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
  2775 #endif
  2776   return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
  2779 // Hint to the underlying OS that a task switch would not be good.
  2780 // Void return because it's a hint and can fail.
  2781 void os::hint_no_preempt() {}
  2783 ////////////////////////////////////////////////////////////////////////////////
  2784 // suspend/resume support
  2786 //  the low-level signal-based suspend/resume support is a remnant from the
  2787 //  old VM-suspension that used to be for java-suspension, safepoints etc,
  2788 //  within hotspot. Now there is a single use-case for this:
  2789 //    - calling get_thread_pc() on the VMThread by the flat-profiler task
  2790 //      that runs in the watcher thread.
  2791 //  The remaining code is greatly simplified from the more general suspension
  2792 //  code that used to be used.
  2793 //
  2794 //  The protocol is quite simple:
  2795 //  - suspend:
  2796 //      - sends a signal to the target thread
  2797 //      - polls the suspend state of the osthread using a yield loop
  2798 //      - target thread signal handler (SR_handler) sets suspend state
  2799 //        and blocks in sigsuspend until continued
  2800 //  - resume:
  2801 //      - sets target osthread state to continue
  2802 //      - sends signal to end the sigsuspend loop in the SR_handler
  2803 //
  2804 //  Note that the SR_lock plays no role in this suspend/resume protocol.
  2805 //
  2807 static void resume_clear_context(OSThread *osthread) {
  2808   osthread->set_ucontext(NULL);
  2809   osthread->set_siginfo(NULL);
  2812 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
  2813   osthread->set_ucontext(context);
  2814   osthread->set_siginfo(siginfo);
  2817 //
  2818 // Handler function invoked when a thread's execution is suspended or
  2819 // resumed. We have to be careful that only async-safe functions are
  2820 // called here (Note: most pthread functions are not async safe and
  2821 // should be avoided.)
  2822 //
  2823 // Note: sigwait() is a more natural fit than sigsuspend() from an
  2824 // interface point of view, but sigwait() prevents the signal hander
  2825 // from being run. libpthread would get very confused by not having
  2826 // its signal handlers run and prevents sigwait()'s use with the
  2827 // mutex granting granting signal.
  2828 //
  2829 // Currently only ever called on the VMThread or JavaThread
  2830 //
  2831 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
  2832   // Save and restore errno to avoid confusing native code with EINTR
  2833   // after sigsuspend.
  2834   int old_errno = errno;
  2836   Thread* thread = Thread::current();
  2837   OSThread* osthread = thread->osthread();
  2838   assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
  2840   os::SuspendResume::State current = osthread->sr.state();
  2841   if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
  2842     suspend_save_context(osthread, siginfo, context);
  2844     // attempt to switch the state, we assume we had a SUSPEND_REQUEST
  2845     os::SuspendResume::State state = osthread->sr.suspended();
  2846     if (state == os::SuspendResume::SR_SUSPENDED) {
  2847       sigset_t suspend_set;  // signals for sigsuspend()
  2849       // get current set of blocked signals and unblock resume signal
  2850       pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
  2851       sigdelset(&suspend_set, SR_signum);
  2853       sr_semaphore.signal();
  2854       // wait here until we are resumed
  2855       while (1) {
  2856         sigsuspend(&suspend_set);
  2858         os::SuspendResume::State result = osthread->sr.running();
  2859         if (result == os::SuspendResume::SR_RUNNING) {
  2860           sr_semaphore.signal();
  2861           break;
  2862         } else if (result != os::SuspendResume::SR_SUSPENDED) {
  2863           ShouldNotReachHere();
  2867     } else if (state == os::SuspendResume::SR_RUNNING) {
  2868       // request was cancelled, continue
  2869     } else {
  2870       ShouldNotReachHere();
  2873     resume_clear_context(osthread);
  2874   } else if (current == os::SuspendResume::SR_RUNNING) {
  2875     // request was cancelled, continue
  2876   } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
  2877     // ignore
  2878   } else {
  2879     // ignore
  2882   errno = old_errno;
  2886 static int SR_initialize() {
  2887   struct sigaction act;
  2888   char *s;
  2889   /* Get signal number to use for suspend/resume */
  2890   if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
  2891     int sig = ::strtol(s, 0, 10);
  2892     if (sig > 0 || sig < NSIG) {
  2893         SR_signum = sig;
  2897   assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
  2898         "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
  2900   sigemptyset(&SR_sigset);
  2901   sigaddset(&SR_sigset, SR_signum);
  2903   /* Set up signal handler for suspend/resume */
  2904   act.sa_flags = SA_RESTART|SA_SIGINFO;
  2905   act.sa_handler = (void (*)(int)) SR_handler;
  2907   // SR_signum is blocked by default.
  2908   // 4528190 - We also need to block pthread restart signal (32 on all
  2909   // supported Bsd platforms). Note that BsdThreads need to block
  2910   // this signal for all threads to work properly. So we don't have
  2911   // to use hard-coded signal number when setting up the mask.
  2912   pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
  2914   if (sigaction(SR_signum, &act, 0) == -1) {
  2915     return -1;
  2918   // Save signal flag
  2919   os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
  2920   return 0;
  2923 static int sr_notify(OSThread* osthread) {
  2924   int status = pthread_kill(osthread->pthread_id(), SR_signum);
  2925   assert_status(status == 0, status, "pthread_kill");
  2926   return status;
  2929 // "Randomly" selected value for how long we want to spin
  2930 // before bailing out on suspending a thread, also how often
  2931 // we send a signal to a thread we want to resume
  2932 static const int RANDOMLY_LARGE_INTEGER = 1000000;
  2933 static const int RANDOMLY_LARGE_INTEGER2 = 100;
  2935 // returns true on success and false on error - really an error is fatal
  2936 // but this seems the normal response to library errors
  2937 static bool do_suspend(OSThread* osthread) {
  2938   assert(osthread->sr.is_running(), "thread should be running");
  2939   assert(!sr_semaphore.trywait(), "semaphore has invalid state");
  2941   // mark as suspended and send signal
  2942   if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
  2943     // failed to switch, state wasn't running?
  2944     ShouldNotReachHere();
  2945     return false;
  2948   if (sr_notify(osthread) != 0) {
  2949     ShouldNotReachHere();
  2952   // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
  2953   while (true) {
  2954     if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
  2955       break;
  2956     } else {
  2957       // timeout
  2958       os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
  2959       if (cancelled == os::SuspendResume::SR_RUNNING) {
  2960         return false;
  2961       } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
  2962         // make sure that we consume the signal on the semaphore as well
  2963         sr_semaphore.wait();
  2964         break;
  2965       } else {
  2966         ShouldNotReachHere();
  2967         return false;
  2972   guarantee(osthread->sr.is_suspended(), "Must be suspended");
  2973   return true;
  2976 static void do_resume(OSThread* osthread) {
  2977   assert(osthread->sr.is_suspended(), "thread should be suspended");
  2978   assert(!sr_semaphore.trywait(), "invalid semaphore state");
  2980   if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
  2981     // failed to switch to WAKEUP_REQUEST
  2982     ShouldNotReachHere();
  2983     return;
  2986   while (true) {
  2987     if (sr_notify(osthread) == 0) {
  2988       if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
  2989         if (osthread->sr.is_running()) {
  2990           return;
  2993     } else {
  2994       ShouldNotReachHere();
  2998   guarantee(osthread->sr.is_running(), "Must be running!");
  3001 ////////////////////////////////////////////////////////////////////////////////
  3002 // interrupt support
  3004 void os::interrupt(Thread* thread) {
  3005   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  3006     "possibility of dangling Thread pointer");
  3008   OSThread* osthread = thread->osthread();
  3010   if (!osthread->interrupted()) {
  3011     osthread->set_interrupted(true);
  3012     // More than one thread can get here with the same value of osthread,
  3013     // resulting in multiple notifications.  We do, however, want the store
  3014     // to interrupted() to be visible to other threads before we execute unpark().
  3015     OrderAccess::fence();
  3016     ParkEvent * const slp = thread->_SleepEvent ;
  3017     if (slp != NULL) slp->unpark() ;
  3020   // For JSR166. Unpark even if interrupt status already was set
  3021   if (thread->is_Java_thread())
  3022     ((JavaThread*)thread)->parker()->unpark();
  3024   ParkEvent * ev = thread->_ParkEvent ;
  3025   if (ev != NULL) ev->unpark() ;
  3029 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
  3030   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  3031     "possibility of dangling Thread pointer");
  3033   OSThread* osthread = thread->osthread();
  3035   bool interrupted = osthread->interrupted();
  3037   if (interrupted && clear_interrupted) {
  3038     osthread->set_interrupted(false);
  3039     // consider thread->_SleepEvent->reset() ... optional optimization
  3042   return interrupted;
  3045 ///////////////////////////////////////////////////////////////////////////////////
  3046 // signal handling (except suspend/resume)
  3048 // This routine may be used by user applications as a "hook" to catch signals.
  3049 // The user-defined signal handler must pass unrecognized signals to this
  3050 // routine, and if it returns true (non-zero), then the signal handler must
  3051 // return immediately.  If the flag "abort_if_unrecognized" is true, then this
  3052 // routine will never retun false (zero), but instead will execute a VM panic
  3053 // routine kill the process.
  3054 //
  3055 // If this routine returns false, it is OK to call it again.  This allows
  3056 // the user-defined signal handler to perform checks either before or after
  3057 // the VM performs its own checks.  Naturally, the user code would be making
  3058 // a serious error if it tried to handle an exception (such as a null check
  3059 // or breakpoint) that the VM was generating for its own correct operation.
  3060 //
  3061 // This routine may recognize any of the following kinds of signals:
  3062 //    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
  3063 // It should be consulted by handlers for any of those signals.
  3064 //
  3065 // The caller of this routine must pass in the three arguments supplied
  3066 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
  3067 // field of the structure passed to sigaction().  This routine assumes that
  3068 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
  3069 //
  3070 // Note that the VM will print warnings if it detects conflicting signal
  3071 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
  3072 //
  3073 extern "C" JNIEXPORT int
  3074 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
  3075                         void* ucontext, int abort_if_unrecognized);
  3077 void signalHandler(int sig, siginfo_t* info, void* uc) {
  3078   assert(info != NULL && uc != NULL, "it must be old kernel");
  3079   int orig_errno = errno;  // Preserve errno value over signal handler.
  3080   JVM_handle_bsd_signal(sig, info, uc, true);
  3081   errno = orig_errno;
  3085 // This boolean allows users to forward their own non-matching signals
  3086 // to JVM_handle_bsd_signal, harmlessly.
  3087 bool os::Bsd::signal_handlers_are_installed = false;
  3089 // For signal-chaining
  3090 struct sigaction os::Bsd::sigact[MAXSIGNUM];
  3091 unsigned int os::Bsd::sigs = 0;
  3092 bool os::Bsd::libjsig_is_loaded = false;
  3093 typedef struct sigaction *(*get_signal_t)(int);
  3094 get_signal_t os::Bsd::get_signal_action = NULL;
  3096 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
  3097   struct sigaction *actp = NULL;
  3099   if (libjsig_is_loaded) {
  3100     // Retrieve the old signal handler from libjsig
  3101     actp = (*get_signal_action)(sig);
  3103   if (actp == NULL) {
  3104     // Retrieve the preinstalled signal handler from jvm
  3105     actp = get_preinstalled_handler(sig);
  3108   return actp;
  3111 static bool call_chained_handler(struct sigaction *actp, int sig,
  3112                                  siginfo_t *siginfo, void *context) {
  3113   // Call the old signal handler
  3114   if (actp->sa_handler == SIG_DFL) {
  3115     // It's more reasonable to let jvm treat it as an unexpected exception
  3116     // instead of taking the default action.
  3117     return false;
  3118   } else if (actp->sa_handler != SIG_IGN) {
  3119     if ((actp->sa_flags & SA_NODEFER) == 0) {
  3120       // automaticlly block the signal
  3121       sigaddset(&(actp->sa_mask), sig);
  3124     sa_handler_t hand;
  3125     sa_sigaction_t sa;
  3126     bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
  3127     // retrieve the chained handler
  3128     if (siginfo_flag_set) {
  3129       sa = actp->sa_sigaction;
  3130     } else {
  3131       hand = actp->sa_handler;
  3134     if ((actp->sa_flags & SA_RESETHAND) != 0) {
  3135       actp->sa_handler = SIG_DFL;
  3138     // try to honor the signal mask
  3139     sigset_t oset;
  3140     pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
  3142     // call into the chained handler
  3143     if (siginfo_flag_set) {
  3144       (*sa)(sig, siginfo, context);
  3145     } else {
  3146       (*hand)(sig);
  3149     // restore the signal mask
  3150     pthread_sigmask(SIG_SETMASK, &oset, 0);
  3152   // Tell jvm's signal handler the signal is taken care of.
  3153   return true;
  3156 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
  3157   bool chained = false;
  3158   // signal-chaining
  3159   if (UseSignalChaining) {
  3160     struct sigaction *actp = get_chained_signal_action(sig);
  3161     if (actp != NULL) {
  3162       chained = call_chained_handler(actp, sig, siginfo, context);
  3165   return chained;
  3168 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
  3169   if ((( (unsigned int)1 << sig ) & sigs) != 0) {
  3170     return &sigact[sig];
  3172   return NULL;
  3175 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
  3176   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3177   sigact[sig] = oldAct;
  3178   sigs |= (unsigned int)1 << sig;
  3181 // for diagnostic
  3182 int os::Bsd::sigflags[MAXSIGNUM];
  3184 int os::Bsd::get_our_sigflags(int sig) {
  3185   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3186   return sigflags[sig];
  3189 void os::Bsd::set_our_sigflags(int sig, int flags) {
  3190   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3191   sigflags[sig] = flags;
  3194 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
  3195   // Check for overwrite.
  3196   struct sigaction oldAct;
  3197   sigaction(sig, (struct sigaction*)NULL, &oldAct);
  3199   void* oldhand = oldAct.sa_sigaction
  3200                 ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
  3201                 : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
  3202   if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
  3203       oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
  3204       oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
  3205     if (AllowUserSignalHandlers || !set_installed) {
  3206       // Do not overwrite; user takes responsibility to forward to us.
  3207       return;
  3208     } else if (UseSignalChaining) {
  3209       // save the old handler in jvm
  3210       save_preinstalled_handler(sig, oldAct);
  3211       // libjsig also interposes the sigaction() call below and saves the
  3212       // old sigaction on it own.
  3213     } else {
  3214       fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
  3215                     "%#lx for signal %d.", (long)oldhand, sig));
  3219   struct sigaction sigAct;
  3220   sigfillset(&(sigAct.sa_mask));
  3221   sigAct.sa_handler = SIG_DFL;
  3222   if (!set_installed) {
  3223     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3224   } else {
  3225     sigAct.sa_sigaction = signalHandler;
  3226     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3228 #if __APPLE__
  3229   // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
  3230   // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
  3231   // if the signal handler declares it will handle it on alternate stack.
  3232   // Notice we only declare we will handle it on alt stack, but we are not
  3233   // actually going to use real alt stack - this is just a workaround.
  3234   // Please see ux_exception.c, method catch_mach_exception_raise for details
  3235   // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
  3236   if (sig == SIGSEGV) {
  3237     sigAct.sa_flags |= SA_ONSTACK;
  3239 #endif
  3241   // Save flags, which are set by ours
  3242   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3243   sigflags[sig] = sigAct.sa_flags;
  3245   int ret = sigaction(sig, &sigAct, &oldAct);
  3246   assert(ret == 0, "check");
  3248   void* oldhand2  = oldAct.sa_sigaction
  3249                   ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
  3250                   : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
  3251   assert(oldhand2 == oldhand, "no concurrent signal handler installation");
  3254 // install signal handlers for signals that HotSpot needs to
  3255 // handle in order to support Java-level exception handling.
  3257 void os::Bsd::install_signal_handlers() {
  3258   if (!signal_handlers_are_installed) {
  3259     signal_handlers_are_installed = true;
  3261     // signal-chaining
  3262     typedef void (*signal_setting_t)();
  3263     signal_setting_t begin_signal_setting = NULL;
  3264     signal_setting_t end_signal_setting = NULL;
  3265     begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3266                              dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
  3267     if (begin_signal_setting != NULL) {
  3268       end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3269                              dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
  3270       get_signal_action = CAST_TO_FN_PTR(get_signal_t,
  3271                             dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
  3272       libjsig_is_loaded = true;
  3273       assert(UseSignalChaining, "should enable signal-chaining");
  3275     if (libjsig_is_loaded) {
  3276       // Tell libjsig jvm is setting signal handlers
  3277       (*begin_signal_setting)();
  3280     set_signal_handler(SIGSEGV, true);
  3281     set_signal_handler(SIGPIPE, true);
  3282     set_signal_handler(SIGBUS, true);
  3283     set_signal_handler(SIGILL, true);
  3284     set_signal_handler(SIGFPE, true);
  3285     set_signal_handler(SIGXFSZ, true);
  3287 #if defined(__APPLE__)
  3288     // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
  3289     // signals caught and handled by the JVM. To work around this, we reset the mach task
  3290     // signal handler that's placed on our process by CrashReporter. This disables
  3291     // CrashReporter-based reporting.
  3292     //
  3293     // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
  3294     // on caught fatal signals.
  3295     //
  3296     // Additionally, gdb installs both standard BSD signal handlers, and mach exception
  3297     // handlers. By replacing the existing task exception handler, we disable gdb's mach
  3298     // exception handling, while leaving the standard BSD signal handlers functional.
  3299     kern_return_t kr;
  3300     kr = task_set_exception_ports(mach_task_self(),
  3301         EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
  3302         MACH_PORT_NULL,
  3303         EXCEPTION_STATE_IDENTITY,
  3304         MACHINE_THREAD_STATE);
  3306     assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
  3307 #endif
  3309     if (libjsig_is_loaded) {
  3310       // Tell libjsig jvm finishes setting signal handlers
  3311       (*end_signal_setting)();
  3314     // We don't activate signal checker if libjsig is in place, we trust ourselves
  3315     // and if UserSignalHandler is installed all bets are off
  3316     if (CheckJNICalls) {
  3317       if (libjsig_is_loaded) {
  3318         if (PrintJNIResolving) {
  3319           tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
  3321         check_signals = false;
  3323       if (AllowUserSignalHandlers) {
  3324         if (PrintJNIResolving) {
  3325           tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
  3327         check_signals = false;
  3334 /////
  3335 // glibc on Bsd platform uses non-documented flag
  3336 // to indicate, that some special sort of signal
  3337 // trampoline is used.
  3338 // We will never set this flag, and we should
  3339 // ignore this flag in our diagnostic
  3340 #ifdef SIGNIFICANT_SIGNAL_MASK
  3341 #undef SIGNIFICANT_SIGNAL_MASK
  3342 #endif
  3343 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
  3345 static const char* get_signal_handler_name(address handler,
  3346                                            char* buf, int buflen) {
  3347   int offset;
  3348   bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
  3349   if (found) {
  3350     // skip directory names
  3351     const char *p1, *p2;
  3352     p1 = buf;
  3353     size_t len = strlen(os::file_separator());
  3354     while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
  3355     jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
  3356   } else {
  3357     jio_snprintf(buf, buflen, PTR_FORMAT, handler);
  3359   return buf;
  3362 static void print_signal_handler(outputStream* st, int sig,
  3363                                  char* buf, size_t buflen) {
  3364   struct sigaction sa;
  3366   sigaction(sig, NULL, &sa);
  3368   // See comment for SIGNIFICANT_SIGNAL_MASK define
  3369   sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3371   st->print("%s: ", os::exception_name(sig, buf, buflen));
  3373   address handler = (sa.sa_flags & SA_SIGINFO)
  3374     ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
  3375     : CAST_FROM_FN_PTR(address, sa.sa_handler);
  3377   if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
  3378     st->print("SIG_DFL");
  3379   } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
  3380     st->print("SIG_IGN");
  3381   } else {
  3382     st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
  3385   st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
  3387   address rh = VMError::get_resetted_sighandler(sig);
  3388   // May be, handler was resetted by VMError?
  3389   if(rh != NULL) {
  3390     handler = rh;
  3391     sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
  3394   st->print(", sa_flags="   PTR32_FORMAT, sa.sa_flags);
  3396   // Check: is it our handler?
  3397   if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
  3398      handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
  3399     // It is our signal handler
  3400     // check for flags, reset system-used one!
  3401     if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3402       st->print(
  3403                 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
  3404                 os::Bsd::get_our_sigflags(sig));
  3407   st->cr();
  3411 #define DO_SIGNAL_CHECK(sig) \
  3412   if (!sigismember(&check_signal_done, sig)) \
  3413     os::Bsd::check_signal_handler(sig)
  3415 // This method is a periodic task to check for misbehaving JNI applications
  3416 // under CheckJNI, we can add any periodic checks here
  3418 void os::run_periodic_checks() {
  3420   if (check_signals == false) return;
  3422   // SEGV and BUS if overridden could potentially prevent
  3423   // generation of hs*.log in the event of a crash, debugging
  3424   // such a case can be very challenging, so we absolutely
  3425   // check the following for a good measure:
  3426   DO_SIGNAL_CHECK(SIGSEGV);
  3427   DO_SIGNAL_CHECK(SIGILL);
  3428   DO_SIGNAL_CHECK(SIGFPE);
  3429   DO_SIGNAL_CHECK(SIGBUS);
  3430   DO_SIGNAL_CHECK(SIGPIPE);
  3431   DO_SIGNAL_CHECK(SIGXFSZ);
  3434   // ReduceSignalUsage allows the user to override these handlers
  3435   // see comments at the very top and jvm_solaris.h
  3436   if (!ReduceSignalUsage) {
  3437     DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
  3438     DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
  3439     DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
  3440     DO_SIGNAL_CHECK(BREAK_SIGNAL);
  3443   DO_SIGNAL_CHECK(SR_signum);
  3444   DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
  3447 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
  3449 static os_sigaction_t os_sigaction = NULL;
  3451 void os::Bsd::check_signal_handler(int sig) {
  3452   char buf[O_BUFLEN];
  3453   address jvmHandler = NULL;
  3456   struct sigaction act;
  3457   if (os_sigaction == NULL) {
  3458     // only trust the default sigaction, in case it has been interposed
  3459     os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
  3460     if (os_sigaction == NULL) return;
  3463   os_sigaction(sig, (struct sigaction*)NULL, &act);
  3466   act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3468   address thisHandler = (act.sa_flags & SA_SIGINFO)
  3469     ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
  3470     : CAST_FROM_FN_PTR(address, act.sa_handler) ;
  3473   switch(sig) {
  3474   case SIGSEGV:
  3475   case SIGBUS:
  3476   case SIGFPE:
  3477   case SIGPIPE:
  3478   case SIGILL:
  3479   case SIGXFSZ:
  3480     jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
  3481     break;
  3483   case SHUTDOWN1_SIGNAL:
  3484   case SHUTDOWN2_SIGNAL:
  3485   case SHUTDOWN3_SIGNAL:
  3486   case BREAK_SIGNAL:
  3487     jvmHandler = (address)user_handler();
  3488     break;
  3490   case INTERRUPT_SIGNAL:
  3491     jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
  3492     break;
  3494   default:
  3495     if (sig == SR_signum) {
  3496       jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
  3497     } else {
  3498       return;
  3500     break;
  3503   if (thisHandler != jvmHandler) {
  3504     tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
  3505     tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
  3506     tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
  3507     // No need to check this sig any longer
  3508     sigaddset(&check_signal_done, sig);
  3509   } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3510     tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
  3511     tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
  3512     tty->print_cr("  found:" PTR32_FORMAT, act.sa_flags);
  3513     // No need to check this sig any longer
  3514     sigaddset(&check_signal_done, sig);
  3517   // Dump all the signal
  3518   if (sigismember(&check_signal_done, sig)) {
  3519     print_signal_handlers(tty, buf, O_BUFLEN);
  3523 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
  3525 extern bool signal_name(int signo, char* buf, size_t len);
  3527 const char* os::exception_name(int exception_code, char* buf, size_t size) {
  3528   if (0 < exception_code && exception_code <= SIGRTMAX) {
  3529     // signal
  3530     if (!signal_name(exception_code, buf, size)) {
  3531       jio_snprintf(buf, size, "SIG%d", exception_code);
  3533     return buf;
  3534   } else {
  3535     return NULL;
  3539 // this is called _before_ the most of global arguments have been parsed
  3540 void os::init(void) {
  3541   char dummy;   /* used to get a guess on initial stack address */
  3542 //  first_hrtime = gethrtime();
  3544   // With BsdThreads the JavaMain thread pid (primordial thread)
  3545   // is different than the pid of the java launcher thread.
  3546   // So, on Bsd, the launcher thread pid is passed to the VM
  3547   // via the sun.java.launcher.pid property.
  3548   // Use this property instead of getpid() if it was correctly passed.
  3549   // See bug 6351349.
  3550   pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
  3552   _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
  3554   clock_tics_per_sec = CLK_TCK;
  3556   init_random(1234567);
  3558   ThreadCritical::initialize();
  3560   Bsd::set_page_size(getpagesize());
  3561   if (Bsd::page_size() == -1) {
  3562     fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
  3563                   strerror(errno)));
  3565   init_page_sizes((size_t) Bsd::page_size());
  3567   Bsd::initialize_system_info();
  3569   // main_thread points to the aboriginal thread
  3570   Bsd::_main_thread = pthread_self();
  3572   Bsd::clock_init();
  3573   initial_time_count = os::elapsed_counter();
  3575 #ifdef __APPLE__
  3576   // XXXDARWIN
  3577   // Work around the unaligned VM callbacks in hotspot's
  3578   // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
  3579   // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
  3580   // alignment when doing symbol lookup. To work around this, we force early
  3581   // binding of all symbols now, thus binding when alignment is known-good.
  3582   _dyld_bind_fully_image_containing_address((const void *) &os::init);
  3583 #endif
  3586 // To install functions for atexit system call
  3587 extern "C" {
  3588   static void perfMemory_exit_helper() {
  3589     perfMemory_exit();
  3593 // this is called _after_ the global arguments have been parsed
  3594 jint os::init_2(void)
  3596   // Allocate a single page and mark it as readable for safepoint polling
  3597   address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3598   guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
  3600   os::set_polling_page( polling_page );
  3602 #ifndef PRODUCT
  3603   if(Verbose && PrintMiscellaneous)
  3604     tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
  3605 #endif
  3607   if (!UseMembar) {
  3608     address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3609     guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
  3610     os::set_memory_serialize_page( mem_serialize_page );
  3612 #ifndef PRODUCT
  3613     if(Verbose && PrintMiscellaneous)
  3614       tty->print("[Memory Serialize  Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
  3615 #endif
  3618   // initialize suspend/resume support - must do this before signal_sets_init()
  3619   if (SR_initialize() != 0) {
  3620     perror("SR_initialize failed");
  3621     return JNI_ERR;
  3624   Bsd::signal_sets_init();
  3625   Bsd::install_signal_handlers();
  3627   // Check minimum allowable stack size for thread creation and to initialize
  3628   // the java system classes, including StackOverflowError - depends on page
  3629   // size.  Add a page for compiler2 recursion in main thread.
  3630   // Add in 2*BytesPerWord times page size to account for VM stack during
  3631   // class initialization depending on 32 or 64 bit VM.
  3632   os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
  3633             (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
  3634                     2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
  3636   size_t threadStackSizeInBytes = ThreadStackSize * K;
  3637   if (threadStackSizeInBytes != 0 &&
  3638       threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
  3639         tty->print_cr("\nThe stack size specified is too small, "
  3640                       "Specify at least %dk",
  3641                       os::Bsd::min_stack_allowed/ K);
  3642         return JNI_ERR;
  3645   // Make the stack size a multiple of the page size so that
  3646   // the yellow/red zones can be guarded.
  3647   JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
  3648         vm_page_size()));
  3650   if (MaxFDLimit) {
  3651     // set the number of file descriptors to max. print out error
  3652     // if getrlimit/setrlimit fails but continue regardless.
  3653     struct rlimit nbr_files;
  3654     int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
  3655     if (status != 0) {
  3656       if (PrintMiscellaneous && (Verbose || WizardMode))
  3657         perror("os::init_2 getrlimit failed");
  3658     } else {
  3659       nbr_files.rlim_cur = nbr_files.rlim_max;
  3661 #ifdef __APPLE__
  3662       // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
  3663       // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
  3664       // be used instead
  3665       nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
  3666 #endif
  3668       status = setrlimit(RLIMIT_NOFILE, &nbr_files);
  3669       if (status != 0) {
  3670         if (PrintMiscellaneous && (Verbose || WizardMode))
  3671           perror("os::init_2 setrlimit failed");
  3676   // at-exit methods are called in the reverse order of their registration.
  3677   // atexit functions are called on return from main or as a result of a
  3678   // call to exit(3C). There can be only 32 of these functions registered
  3679   // and atexit() does not set errno.
  3681   if (PerfAllowAtExitRegistration) {
  3682     // only register atexit functions if PerfAllowAtExitRegistration is set.
  3683     // atexit functions can be delayed until process exit time, which
  3684     // can be problematic for embedded VM situations. Embedded VMs should
  3685     // call DestroyJavaVM() to assure that VM resources are released.
  3687     // note: perfMemory_exit_helper atexit function may be removed in
  3688     // the future if the appropriate cleanup code can be added to the
  3689     // VM_Exit VMOperation's doit method.
  3690     if (atexit(perfMemory_exit_helper) != 0) {
  3691       warning("os::init2 atexit(perfMemory_exit_helper) failed");
  3695   // initialize thread priority policy
  3696   prio_init();
  3698 #ifdef __APPLE__
  3699   // dynamically link to objective c gc registration
  3700   void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
  3701   if (handleLibObjc != NULL) {
  3702     objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
  3704 #endif
  3706   return JNI_OK;
  3709 // this is called at the end of vm_initialization
  3710 void os::init_3(void) { }
  3712 // Mark the polling page as unreadable
  3713 void os::make_polling_page_unreadable(void) {
  3714   if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
  3715     fatal("Could not disable polling page");
  3716 };
  3718 // Mark the polling page as readable
  3719 void os::make_polling_page_readable(void) {
  3720   if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
  3721     fatal("Could not enable polling page");
  3723 };
  3725 int os::active_processor_count() {
  3726   return _processor_count;
  3729 void os::set_native_thread_name(const char *name) {
  3730 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
  3731   // This is only supported in Snow Leopard and beyond
  3732   if (name != NULL) {
  3733     // Add a "Java: " prefix to the name
  3734     char buf[MAXTHREADNAMESIZE];
  3735     snprintf(buf, sizeof(buf), "Java: %s", name);
  3736     pthread_setname_np(buf);
  3738 #endif
  3741 bool os::distribute_processes(uint length, uint* distribution) {
  3742   // Not yet implemented.
  3743   return false;
  3746 bool os::bind_to_processor(uint processor_id) {
  3747   // Not yet implemented.
  3748   return false;
  3751 void os::SuspendedThreadTask::internal_do_task() {
  3752   if (do_suspend(_thread->osthread())) {
  3753     SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
  3754     do_task(context);
  3755     do_resume(_thread->osthread());
  3759 ///
  3760 class PcFetcher : public os::SuspendedThreadTask {
  3761 public:
  3762   PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
  3763   ExtendedPC result();
  3764 protected:
  3765   void do_task(const os::SuspendedThreadTaskContext& context);
  3766 private:
  3767   ExtendedPC _epc;
  3768 };
  3770 ExtendedPC PcFetcher::result() {
  3771   guarantee(is_done(), "task is not done yet.");
  3772   return _epc;
  3775 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
  3776   Thread* thread = context.thread();
  3777   OSThread* osthread = thread->osthread();
  3778   if (osthread->ucontext() != NULL) {
  3779     _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
  3780   } else {
  3781     // NULL context is unexpected, double-check this is the VMThread
  3782     guarantee(thread->is_VM_thread(), "can only be called for VMThread");
  3786 // Suspends the target using the signal mechanism and then grabs the PC before
  3787 // resuming the target. Used by the flat-profiler only
  3788 ExtendedPC os::get_thread_pc(Thread* thread) {
  3789   // Make sure that it is called by the watcher for the VMThread
  3790   assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
  3791   assert(thread->is_VM_thread(), "Can only be called for VMThread");
  3793   PcFetcher fetcher(thread);
  3794   fetcher.run();
  3795   return fetcher.result();
  3798 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
  3800   return pthread_cond_timedwait(_cond, _mutex, _abstime);
  3803 ////////////////////////////////////////////////////////////////////////////////
  3804 // debug support
  3806 bool os::find(address addr, outputStream* st) {
  3807   Dl_info dlinfo;
  3808   memset(&dlinfo, 0, sizeof(dlinfo));
  3809   if (dladdr(addr, &dlinfo) != 0) {
  3810     st->print(PTR_FORMAT ": ", addr);
  3811     if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
  3812       st->print("%s+%#x", dlinfo.dli_sname,
  3813                  addr - (intptr_t)dlinfo.dli_saddr);
  3814     } else if (dlinfo.dli_fbase != NULL) {
  3815       st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
  3816     } else {
  3817       st->print("<absolute address>");
  3819     if (dlinfo.dli_fname != NULL) {
  3820       st->print(" in %s", dlinfo.dli_fname);
  3822     if (dlinfo.dli_fbase != NULL) {
  3823       st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
  3825     st->cr();
  3827     if (Verbose) {
  3828       // decode some bytes around the PC
  3829       address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
  3830       address end   = clamp_address_in_page(addr+40, addr, os::vm_page_size());
  3831       address       lowest = (address) dlinfo.dli_sname;
  3832       if (!lowest)  lowest = (address) dlinfo.dli_fbase;
  3833       if (begin < lowest)  begin = lowest;
  3834       Dl_info dlinfo2;
  3835       if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
  3836           && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
  3837         end = (address) dlinfo2.dli_saddr;
  3838       Disassembler::decode(begin, end, st);
  3840     return true;
  3842   return false;
  3845 ////////////////////////////////////////////////////////////////////////////////
  3846 // misc
  3848 // This does not do anything on Bsd. This is basically a hook for being
  3849 // able to use structured exception handling (thread-local exception filters)
  3850 // on, e.g., Win32.
  3851 void
  3852 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
  3853                          JavaCallArguments* args, Thread* thread) {
  3854   f(value, method, args, thread);
  3857 void os::print_statistics() {
  3860 int os::message_box(const char* title, const char* message) {
  3861   int i;
  3862   fdStream err(defaultStream::error_fd());
  3863   for (i = 0; i < 78; i++) err.print_raw("=");
  3864   err.cr();
  3865   err.print_raw_cr(title);
  3866   for (i = 0; i < 78; i++) err.print_raw("-");
  3867   err.cr();
  3868   err.print_raw_cr(message);
  3869   for (i = 0; i < 78; i++) err.print_raw("=");
  3870   err.cr();
  3872   char buf[16];
  3873   // Prevent process from exiting upon "read error" without consuming all CPU
  3874   while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
  3876   return buf[0] == 'y' || buf[0] == 'Y';
  3879 int os::stat(const char *path, struct stat *sbuf) {
  3880   char pathbuf[MAX_PATH];
  3881   if (strlen(path) > MAX_PATH - 1) {
  3882     errno = ENAMETOOLONG;
  3883     return -1;
  3885   os::native_path(strcpy(pathbuf, path));
  3886   return ::stat(pathbuf, sbuf);
  3889 bool os::check_heap(bool force) {
  3890   return true;
  3893 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
  3894   return ::vsnprintf(buf, count, format, args);
  3897 // Is a (classpath) directory empty?
  3898 bool os::dir_is_empty(const char* path) {
  3899   DIR *dir = NULL;
  3900   struct dirent *ptr;
  3902   dir = opendir(path);
  3903   if (dir == NULL) return true;
  3905   /* Scan the directory */
  3906   bool result = true;
  3907   char buf[sizeof(struct dirent) + MAX_PATH];
  3908   while (result && (ptr = ::readdir(dir)) != NULL) {
  3909     if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
  3910       result = false;
  3913   closedir(dir);
  3914   return result;
  3917 // This code originates from JDK's sysOpen and open64_w
  3918 // from src/solaris/hpi/src/system_md.c
  3920 #ifndef O_DELETE
  3921 #define O_DELETE 0x10000
  3922 #endif
  3924 // Open a file. Unlink the file immediately after open returns
  3925 // if the specified oflag has the O_DELETE flag set.
  3926 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
  3928 int os::open(const char *path, int oflag, int mode) {
  3930   if (strlen(path) > MAX_PATH - 1) {
  3931     errno = ENAMETOOLONG;
  3932     return -1;
  3934   int fd;
  3935   int o_delete = (oflag & O_DELETE);
  3936   oflag = oflag & ~O_DELETE;
  3938   fd = ::open(path, oflag, mode);
  3939   if (fd == -1) return -1;
  3941   //If the open succeeded, the file might still be a directory
  3943     struct stat buf;
  3944     int ret = ::fstat(fd, &buf);
  3945     int st_mode = buf.st_mode;
  3947     if (ret != -1) {
  3948       if ((st_mode & S_IFMT) == S_IFDIR) {
  3949         errno = EISDIR;
  3950         ::close(fd);
  3951         return -1;
  3953     } else {
  3954       ::close(fd);
  3955       return -1;
  3959     /*
  3960      * All file descriptors that are opened in the JVM and not
  3961      * specifically destined for a subprocess should have the
  3962      * close-on-exec flag set.  If we don't set it, then careless 3rd
  3963      * party native code might fork and exec without closing all
  3964      * appropriate file descriptors (e.g. as we do in closeDescriptors in
  3965      * UNIXProcess.c), and this in turn might:
  3967      * - cause end-of-file to fail to be detected on some file
  3968      *   descriptors, resulting in mysterious hangs, or
  3970      * - might cause an fopen in the subprocess to fail on a system
  3971      *   suffering from bug 1085341.
  3973      * (Yes, the default setting of the close-on-exec flag is a Unix
  3974      * design flaw)
  3976      * See:
  3977      * 1085341: 32-bit stdio routines should support file descriptors >255
  3978      * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
  3979      * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
  3980      */
  3981 #ifdef FD_CLOEXEC
  3983         int flags = ::fcntl(fd, F_GETFD);
  3984         if (flags != -1)
  3985             ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
  3987 #endif
  3989   if (o_delete != 0) {
  3990     ::unlink(path);
  3992   return fd;
  3996 // create binary file, rewriting existing file if required
  3997 int os::create_binary_file(const char* path, bool rewrite_existing) {
  3998   int oflags = O_WRONLY | O_CREAT;
  3999   if (!rewrite_existing) {
  4000     oflags |= O_EXCL;
  4002   return ::open(path, oflags, S_IREAD | S_IWRITE);
  4005 // return current position of file pointer
  4006 jlong os::current_file_offset(int fd) {
  4007   return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
  4010 // move file pointer to the specified offset
  4011 jlong os::seek_to_file_offset(int fd, jlong offset) {
  4012   return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
  4015 // This code originates from JDK's sysAvailable
  4016 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
  4018 int os::available(int fd, jlong *bytes) {
  4019   jlong cur, end;
  4020   int mode;
  4021   struct stat buf;
  4023   if (::fstat(fd, &buf) >= 0) {
  4024     mode = buf.st_mode;
  4025     if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
  4026       /*
  4027       * XXX: is the following call interruptible? If so, this might
  4028       * need to go through the INTERRUPT_IO() wrapper as for other
  4029       * blocking, interruptible calls in this file.
  4030       */
  4031       int n;
  4032       if (::ioctl(fd, FIONREAD, &n) >= 0) {
  4033         *bytes = n;
  4034         return 1;
  4038   if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
  4039     return 0;
  4040   } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
  4041     return 0;
  4042   } else if (::lseek(fd, cur, SEEK_SET) == -1) {
  4043     return 0;
  4045   *bytes = end - cur;
  4046   return 1;
  4049 int os::socket_available(int fd, jint *pbytes) {
  4050    if (fd < 0)
  4051      return OS_OK;
  4053    int ret;
  4055    RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
  4057    //%% note ioctl can return 0 when successful, JVM_SocketAvailable
  4058    // is expected to return 0 on failure and 1 on success to the jdk.
  4060    return (ret == OS_ERR) ? 0 : 1;
  4063 // Map a block of memory.
  4064 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
  4065                      char *addr, size_t bytes, bool read_only,
  4066                      bool allow_exec) {
  4067   int prot;
  4068   int flags;
  4070   if (read_only) {
  4071     prot = PROT_READ;
  4072     flags = MAP_SHARED;
  4073   } else {
  4074     prot = PROT_READ | PROT_WRITE;
  4075     flags = MAP_PRIVATE;
  4078   if (allow_exec) {
  4079     prot |= PROT_EXEC;
  4082   if (addr != NULL) {
  4083     flags |= MAP_FIXED;
  4086   char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
  4087                                      fd, file_offset);
  4088   if (mapped_address == MAP_FAILED) {
  4089     return NULL;
  4091   return mapped_address;
  4095 // Remap a block of memory.
  4096 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
  4097                        char *addr, size_t bytes, bool read_only,
  4098                        bool allow_exec) {
  4099   // same as map_memory() on this OS
  4100   return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
  4101                         allow_exec);
  4105 // Unmap a block of memory.
  4106 bool os::pd_unmap_memory(char* addr, size_t bytes) {
  4107   return munmap(addr, bytes) == 0;
  4110 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
  4111 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
  4112 // of a thread.
  4113 //
  4114 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
  4115 // the fast estimate available on the platform.
  4117 jlong os::current_thread_cpu_time() {
  4118 #ifdef __APPLE__
  4119   return os::thread_cpu_time(Thread::current(), true /* user + sys */);
  4120 #else
  4121   Unimplemented();
  4122   return 0;
  4123 #endif
  4126 jlong os::thread_cpu_time(Thread* thread) {
  4127 #ifdef __APPLE__
  4128   return os::thread_cpu_time(thread, true /* user + sys */);
  4129 #else
  4130   Unimplemented();
  4131   return 0;
  4132 #endif
  4135 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
  4136 #ifdef __APPLE__
  4137   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
  4138 #else
  4139   Unimplemented();
  4140   return 0;
  4141 #endif
  4144 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
  4145 #ifdef __APPLE__
  4146   struct thread_basic_info tinfo;
  4147   mach_msg_type_number_t tcount = THREAD_INFO_MAX;
  4148   kern_return_t kr;
  4149   thread_t mach_thread;
  4151   mach_thread = thread->osthread()->thread_id();
  4152   kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
  4153   if (kr != KERN_SUCCESS)
  4154     return -1;
  4156   if (user_sys_cpu_time) {
  4157     jlong nanos;
  4158     nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
  4159     nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
  4160     return nanos;
  4161   } else {
  4162     return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
  4164 #else
  4165   Unimplemented();
  4166   return 0;
  4167 #endif
  4171 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  4172   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  4173   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  4174   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  4175   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  4178 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  4179   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  4180   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  4181   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  4182   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  4185 bool os::is_thread_cpu_time_supported() {
  4186 #ifdef __APPLE__
  4187   return true;
  4188 #else
  4189   return false;
  4190 #endif
  4193 // System loadavg support.  Returns -1 if load average cannot be obtained.
  4194 // Bsd doesn't yet have a (official) notion of processor sets,
  4195 // so just return the system wide load average.
  4196 int os::loadavg(double loadavg[], int nelem) {
  4197   return ::getloadavg(loadavg, nelem);
  4200 void os::pause() {
  4201   char filename[MAX_PATH];
  4202   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
  4203     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
  4204   } else {
  4205     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
  4208   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
  4209   if (fd != -1) {
  4210     struct stat buf;
  4211     ::close(fd);
  4212     while (::stat(filename, &buf) == 0) {
  4213       (void)::poll(NULL, 0, 100);
  4215   } else {
  4216     jio_fprintf(stderr,
  4217       "Could not open pause file '%s', continuing immediately.\n", filename);
  4222 // Refer to the comments in os_solaris.cpp park-unpark.
  4223 //
  4224 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
  4225 // hang indefinitely.  For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
  4226 // For specifics regarding the bug see GLIBC BUGID 261237 :
  4227 //    http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
  4228 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
  4229 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
  4230 // is used.  (The simple C test-case provided in the GLIBC bug report manifests the
  4231 // hang).  The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
  4232 // and monitorenter when we're using 1-0 locking.  All those operations may result in
  4233 // calls to pthread_cond_timedwait().  Using LD_ASSUME_KERNEL to use an older version
  4234 // of libpthread avoids the problem, but isn't practical.
  4235 //
  4236 // Possible remedies:
  4237 //
  4238 // 1.   Establish a minimum relative wait time.  50 to 100 msecs seems to work.
  4239 //      This is palliative and probabilistic, however.  If the thread is preempted
  4240 //      between the call to compute_abstime() and pthread_cond_timedwait(), more
  4241 //      than the minimum period may have passed, and the abstime may be stale (in the
  4242 //      past) resultin in a hang.   Using this technique reduces the odds of a hang
  4243 //      but the JVM is still vulnerable, particularly on heavily loaded systems.
  4244 //
  4245 // 2.   Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
  4246 //      of the usual flag-condvar-mutex idiom.  The write side of the pipe is set
  4247 //      NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
  4248 //      reduces to poll()+read().  This works well, but consumes 2 FDs per extant
  4249 //      thread.
  4250 //
  4251 // 3.   Embargo pthread_cond_timedwait() and implement a native "chron" thread
  4252 //      that manages timeouts.  We'd emulate pthread_cond_timedwait() by enqueuing
  4253 //      a timeout request to the chron thread and then blocking via pthread_cond_wait().
  4254 //      This also works well.  In fact it avoids kernel-level scalability impediments
  4255 //      on certain platforms that don't handle lots of active pthread_cond_timedwait()
  4256 //      timers in a graceful fashion.
  4257 //
  4258 // 4.   When the abstime value is in the past it appears that control returns
  4259 //      correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
  4260 //      Subsequent timedwait/wait calls may hang indefinitely.  Given that, we
  4261 //      can avoid the problem by reinitializing the condvar -- by cond_destroy()
  4262 //      followed by cond_init() -- after all calls to pthread_cond_timedwait().
  4263 //      It may be possible to avoid reinitialization by checking the return
  4264 //      value from pthread_cond_timedwait().  In addition to reinitializing the
  4265 //      condvar we must establish the invariant that cond_signal() is only called
  4266 //      within critical sections protected by the adjunct mutex.  This prevents
  4267 //      cond_signal() from "seeing" a condvar that's in the midst of being
  4268 //      reinitialized or that is corrupt.  Sadly, this invariant obviates the
  4269 //      desirable signal-after-unlock optimization that avoids futile context switching.
  4270 //
  4271 //      I'm also concerned that some versions of NTPL might allocate an auxilliary
  4272 //      structure when a condvar is used or initialized.  cond_destroy()  would
  4273 //      release the helper structure.  Our reinitialize-after-timedwait fix
  4274 //      put excessive stress on malloc/free and locks protecting the c-heap.
  4275 //
  4276 // We currently use (4).  See the WorkAroundNTPLTimedWaitHang flag.
  4277 // It may be possible to refine (4) by checking the kernel and NTPL verisons
  4278 // and only enabling the work-around for vulnerable environments.
  4280 // utility to compute the abstime argument to timedwait:
  4281 // millis is the relative timeout time
  4282 // abstime will be the absolute timeout time
  4283 // TODO: replace compute_abstime() with unpackTime()
  4285 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
  4286   if (millis < 0)  millis = 0;
  4287   struct timeval now;
  4288   int status = gettimeofday(&now, NULL);
  4289   assert(status == 0, "gettimeofday");
  4290   jlong seconds = millis / 1000;
  4291   millis %= 1000;
  4292   if (seconds > 50000000) { // see man cond_timedwait(3T)
  4293     seconds = 50000000;
  4295   abstime->tv_sec = now.tv_sec  + seconds;
  4296   long       usec = now.tv_usec + millis * 1000;
  4297   if (usec >= 1000000) {
  4298     abstime->tv_sec += 1;
  4299     usec -= 1000000;
  4301   abstime->tv_nsec = usec * 1000;
  4302   return abstime;
  4306 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
  4307 // Conceptually TryPark() should be equivalent to park(0).
  4309 int os::PlatformEvent::TryPark() {
  4310   for (;;) {
  4311     const int v = _Event ;
  4312     guarantee ((v == 0) || (v == 1), "invariant") ;
  4313     if (Atomic::cmpxchg (0, &_Event, v) == v) return v  ;
  4317 void os::PlatformEvent::park() {       // AKA "down()"
  4318   // Invariant: Only the thread associated with the Event/PlatformEvent
  4319   // may call park().
  4320   // TODO: assert that _Assoc != NULL or _Assoc == Self
  4321   int v ;
  4322   for (;;) {
  4323       v = _Event ;
  4324       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4326   guarantee (v >= 0, "invariant") ;
  4327   if (v == 0) {
  4328      // Do this the hard way by blocking ...
  4329      int status = pthread_mutex_lock(_mutex);
  4330      assert_status(status == 0, status, "mutex_lock");
  4331      guarantee (_nParked == 0, "invariant") ;
  4332      ++ _nParked ;
  4333      while (_Event < 0) {
  4334         status = pthread_cond_wait(_cond, _mutex);
  4335         // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
  4336         // Treat this the same as if the wait was interrupted
  4337         if (status == ETIMEDOUT) { status = EINTR; }
  4338         assert_status(status == 0 || status == EINTR, status, "cond_wait");
  4340      -- _nParked ;
  4342     _Event = 0 ;
  4343      status = pthread_mutex_unlock(_mutex);
  4344      assert_status(status == 0, status, "mutex_unlock");
  4345     // Paranoia to ensure our locked and lock-free paths interact
  4346     // correctly with each other.
  4347     OrderAccess::fence();
  4349   guarantee (_Event >= 0, "invariant") ;
  4352 int os::PlatformEvent::park(jlong millis) {
  4353   guarantee (_nParked == 0, "invariant") ;
  4355   int v ;
  4356   for (;;) {
  4357       v = _Event ;
  4358       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4360   guarantee (v >= 0, "invariant") ;
  4361   if (v != 0) return OS_OK ;
  4363   // We do this the hard way, by blocking the thread.
  4364   // Consider enforcing a minimum timeout value.
  4365   struct timespec abst;
  4366   compute_abstime(&abst, millis);
  4368   int ret = OS_TIMEOUT;
  4369   int status = pthread_mutex_lock(_mutex);
  4370   assert_status(status == 0, status, "mutex_lock");
  4371   guarantee (_nParked == 0, "invariant") ;
  4372   ++_nParked ;
  4374   // Object.wait(timo) will return because of
  4375   // (a) notification
  4376   // (b) timeout
  4377   // (c) thread.interrupt
  4378   //
  4379   // Thread.interrupt and object.notify{All} both call Event::set.
  4380   // That is, we treat thread.interrupt as a special case of notification.
  4381   // The underlying Solaris implementation, cond_timedwait, admits
  4382   // spurious/premature wakeups, but the JLS/JVM spec prevents the
  4383   // JVM from making those visible to Java code.  As such, we must
  4384   // filter out spurious wakeups.  We assume all ETIME returns are valid.
  4385   //
  4386   // TODO: properly differentiate simultaneous notify+interrupt.
  4387   // In that case, we should propagate the notify to another waiter.
  4389   while (_Event < 0) {
  4390     status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
  4391     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4392       pthread_cond_destroy (_cond);
  4393       pthread_cond_init (_cond, NULL) ;
  4395     assert_status(status == 0 || status == EINTR ||
  4396                   status == ETIMEDOUT,
  4397                   status, "cond_timedwait");
  4398     if (!FilterSpuriousWakeups) break ;                 // previous semantics
  4399     if (status == ETIMEDOUT) break ;
  4400     // We consume and ignore EINTR and spurious wakeups.
  4402   --_nParked ;
  4403   if (_Event >= 0) {
  4404      ret = OS_OK;
  4406   _Event = 0 ;
  4407   status = pthread_mutex_unlock(_mutex);
  4408   assert_status(status == 0, status, "mutex_unlock");
  4409   assert (_nParked == 0, "invariant") ;
  4410   // Paranoia to ensure our locked and lock-free paths interact
  4411   // correctly with each other.
  4412   OrderAccess::fence();
  4413   return ret;
  4416 void os::PlatformEvent::unpark() {
  4417   // Transitions for _Event:
  4418   //    0 :=> 1
  4419   //    1 :=> 1
  4420   //   -1 :=> either 0 or 1; must signal target thread
  4421   //          That is, we can safely transition _Event from -1 to either
  4422   //          0 or 1. Forcing 1 is slightly more efficient for back-to-back
  4423   //          unpark() calls.
  4424   // See also: "Semaphores in Plan 9" by Mullender & Cox
  4425   //
  4426   // Note: Forcing a transition from "-1" to "1" on an unpark() means
  4427   // that it will take two back-to-back park() calls for the owning
  4428   // thread to block. This has the benefit of forcing a spurious return
  4429   // from the first park() call after an unpark() call which will help
  4430   // shake out uses of park() and unpark() without condition variables.
  4432   if (Atomic::xchg(1, &_Event) >= 0) return;
  4434   // Wait for the thread associated with the event to vacate
  4435   int status = pthread_mutex_lock(_mutex);
  4436   assert_status(status == 0, status, "mutex_lock");
  4437   int AnyWaiters = _nParked;
  4438   assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
  4439   if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
  4440     AnyWaiters = 0;
  4441     pthread_cond_signal(_cond);
  4443   status = pthread_mutex_unlock(_mutex);
  4444   assert_status(status == 0, status, "mutex_unlock");
  4445   if (AnyWaiters != 0) {
  4446     status = pthread_cond_signal(_cond);
  4447     assert_status(status == 0, status, "cond_signal");
  4450   // Note that we signal() _after dropping the lock for "immortal" Events.
  4451   // This is safe and avoids a common class of  futile wakeups.  In rare
  4452   // circumstances this can cause a thread to return prematurely from
  4453   // cond_{timed}wait() but the spurious wakeup is benign and the victim will
  4454   // simply re-test the condition and re-park itself.
  4458 // JSR166
  4459 // -------------------------------------------------------
  4461 /*
  4462  * The solaris and bsd implementations of park/unpark are fairly
  4463  * conservative for now, but can be improved. They currently use a
  4464  * mutex/condvar pair, plus a a count.
  4465  * Park decrements count if > 0, else does a condvar wait.  Unpark
  4466  * sets count to 1 and signals condvar.  Only one thread ever waits
  4467  * on the condvar. Contention seen when trying to park implies that someone
  4468  * is unparking you, so don't wait. And spurious returns are fine, so there
  4469  * is no need to track notifications.
  4470  */
  4472 #define MAX_SECS 100000000
  4473 /*
  4474  * This code is common to bsd and solaris and will be moved to a
  4475  * common place in dolphin.
  4477  * The passed in time value is either a relative time in nanoseconds
  4478  * or an absolute time in milliseconds. Either way it has to be unpacked
  4479  * into suitable seconds and nanoseconds components and stored in the
  4480  * given timespec structure.
  4481  * Given time is a 64-bit value and the time_t used in the timespec is only
  4482  * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
  4483  * overflow if times way in the future are given. Further on Solaris versions
  4484  * prior to 10 there is a restriction (see cond_timedwait) that the specified
  4485  * number of seconds, in abstime, is less than current_time  + 100,000,000.
  4486  * As it will be 28 years before "now + 100000000" will overflow we can
  4487  * ignore overflow and just impose a hard-limit on seconds using the value
  4488  * of "now + 100,000,000". This places a limit on the timeout of about 3.17
  4489  * years from "now".
  4490  */
  4492 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
  4493   assert (time > 0, "convertTime");
  4495   struct timeval now;
  4496   int status = gettimeofday(&now, NULL);
  4497   assert(status == 0, "gettimeofday");
  4499   time_t max_secs = now.tv_sec + MAX_SECS;
  4501   if (isAbsolute) {
  4502     jlong secs = time / 1000;
  4503     if (secs > max_secs) {
  4504       absTime->tv_sec = max_secs;
  4506     else {
  4507       absTime->tv_sec = secs;
  4509     absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
  4511   else {
  4512     jlong secs = time / NANOSECS_PER_SEC;
  4513     if (secs >= MAX_SECS) {
  4514       absTime->tv_sec = max_secs;
  4515       absTime->tv_nsec = 0;
  4517     else {
  4518       absTime->tv_sec = now.tv_sec + secs;
  4519       absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
  4520       if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
  4521         absTime->tv_nsec -= NANOSECS_PER_SEC;
  4522         ++absTime->tv_sec; // note: this must be <= max_secs
  4526   assert(absTime->tv_sec >= 0, "tv_sec < 0");
  4527   assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
  4528   assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
  4529   assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
  4532 void Parker::park(bool isAbsolute, jlong time) {
  4533   // Ideally we'd do something useful while spinning, such
  4534   // as calling unpackTime().
  4536   // Optional fast-path check:
  4537   // Return immediately if a permit is available.
  4538   // We depend on Atomic::xchg() having full barrier semantics
  4539   // since we are doing a lock-free update to _counter.
  4540   if (Atomic::xchg(0, &_counter) > 0) return;
  4542   Thread* thread = Thread::current();
  4543   assert(thread->is_Java_thread(), "Must be JavaThread");
  4544   JavaThread *jt = (JavaThread *)thread;
  4546   // Optional optimization -- avoid state transitions if there's an interrupt pending.
  4547   // Check interrupt before trying to wait
  4548   if (Thread::is_interrupted(thread, false)) {
  4549     return;
  4552   // Next, demultiplex/decode time arguments
  4553   struct timespec absTime;
  4554   if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
  4555     return;
  4557   if (time > 0) {
  4558     unpackTime(&absTime, isAbsolute, time);
  4562   // Enter safepoint region
  4563   // Beware of deadlocks such as 6317397.
  4564   // The per-thread Parker:: mutex is a classic leaf-lock.
  4565   // In particular a thread must never block on the Threads_lock while
  4566   // holding the Parker:: mutex.  If safepoints are pending both the
  4567   // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
  4568   ThreadBlockInVM tbivm(jt);
  4570   // Don't wait if cannot get lock since interference arises from
  4571   // unblocking.  Also. check interrupt before trying wait
  4572   if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
  4573     return;
  4576   int status ;
  4577   if (_counter > 0)  { // no wait needed
  4578     _counter = 0;
  4579     status = pthread_mutex_unlock(_mutex);
  4580     assert (status == 0, "invariant") ;
  4581     // Paranoia to ensure our locked and lock-free paths interact
  4582     // correctly with each other and Java-level accesses.
  4583     OrderAccess::fence();
  4584     return;
  4587 #ifdef ASSERT
  4588   // Don't catch signals while blocked; let the running threads have the signals.
  4589   // (This allows a debugger to break into the running thread.)
  4590   sigset_t oldsigs;
  4591   sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
  4592   pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
  4593 #endif
  4595   OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  4596   jt->set_suspend_equivalent();
  4597   // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  4599   if (time == 0) {
  4600     status = pthread_cond_wait (_cond, _mutex) ;
  4601   } else {
  4602     status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
  4603     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4604       pthread_cond_destroy (_cond) ;
  4605       pthread_cond_init    (_cond, NULL);
  4608   assert_status(status == 0 || status == EINTR ||
  4609                 status == ETIMEDOUT,
  4610                 status, "cond_timedwait");
  4612 #ifdef ASSERT
  4613   pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
  4614 #endif
  4616   _counter = 0 ;
  4617   status = pthread_mutex_unlock(_mutex) ;
  4618   assert_status(status == 0, status, "invariant") ;
  4619   // Paranoia to ensure our locked and lock-free paths interact
  4620   // correctly with each other and Java-level accesses.
  4621   OrderAccess::fence();
  4623   // If externally suspended while waiting, re-suspend
  4624   if (jt->handle_special_suspend_equivalent_condition()) {
  4625     jt->java_suspend_self();
  4629 void Parker::unpark() {
  4630   int s, status ;
  4631   status = pthread_mutex_lock(_mutex);
  4632   assert (status == 0, "invariant") ;
  4633   s = _counter;
  4634   _counter = 1;
  4635   if (s < 1) {
  4636      if (WorkAroundNPTLTimedWaitHang) {
  4637         status = pthread_cond_signal (_cond) ;
  4638         assert (status == 0, "invariant") ;
  4639         status = pthread_mutex_unlock(_mutex);
  4640         assert (status == 0, "invariant") ;
  4641      } else {
  4642         status = pthread_mutex_unlock(_mutex);
  4643         assert (status == 0, "invariant") ;
  4644         status = pthread_cond_signal (_cond) ;
  4645         assert (status == 0, "invariant") ;
  4647   } else {
  4648     pthread_mutex_unlock(_mutex);
  4649     assert (status == 0, "invariant") ;
  4654 /* Darwin has no "environ" in a dynamic library. */
  4655 #ifdef __APPLE__
  4656 #include <crt_externs.h>
  4657 #define environ (*_NSGetEnviron())
  4658 #else
  4659 extern char** environ;
  4660 #endif
  4662 // Run the specified command in a separate process. Return its exit value,
  4663 // or -1 on failure (e.g. can't fork a new process).
  4664 // Unlike system(), this function can be called from signal handler. It
  4665 // doesn't block SIGINT et al.
  4666 int os::fork_and_exec(char* cmd) {
  4667   const char * argv[4] = {"sh", "-c", cmd, NULL};
  4669   // fork() in BsdThreads/NPTL is not async-safe. It needs to run
  4670   // pthread_atfork handlers and reset pthread library. All we need is a
  4671   // separate process to execve. Make a direct syscall to fork process.
  4672   // On IA64 there's no fork syscall, we have to use fork() and hope for
  4673   // the best...
  4674   pid_t pid = fork();
  4676   if (pid < 0) {
  4677     // fork failed
  4678     return -1;
  4680   } else if (pid == 0) {
  4681     // child process
  4683     // execve() in BsdThreads will call pthread_kill_other_threads_np()
  4684     // first to kill every thread on the thread list. Because this list is
  4685     // not reset by fork() (see notes above), execve() will instead kill
  4686     // every thread in the parent process. We know this is the only thread
  4687     // in the new process, so make a system call directly.
  4688     // IA64 should use normal execve() from glibc to match the glibc fork()
  4689     // above.
  4690     execve("/bin/sh", (char* const*)argv, environ);
  4692     // execve failed
  4693     _exit(-1);
  4695   } else  {
  4696     // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
  4697     // care about the actual exit code, for now.
  4699     int status;
  4701     // Wait for the child process to exit.  This returns immediately if
  4702     // the child has already exited. */
  4703     while (waitpid(pid, &status, 0) < 0) {
  4704         switch (errno) {
  4705         case ECHILD: return 0;
  4706         case EINTR: break;
  4707         default: return -1;
  4711     if (WIFEXITED(status)) {
  4712        // The child exited normally; get its exit code.
  4713        return WEXITSTATUS(status);
  4714     } else if (WIFSIGNALED(status)) {
  4715        // The child exited because of a signal
  4716        // The best value to return is 0x80 + signal number,
  4717        // because that is what all Unix shells do, and because
  4718        // it allows callers to distinguish between process exit and
  4719        // process death by signal.
  4720        return 0x80 + WTERMSIG(status);
  4721     } else {
  4722        // Unknown exit code; pass it through
  4723        return status;
  4728 // is_headless_jre()
  4729 //
  4730 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
  4731 // in order to report if we are running in a headless jre
  4732 //
  4733 // Since JDK8 xawt/libmawt.so was moved into the same directory
  4734 // as libawt.so, and renamed libawt_xawt.so
  4735 //
  4736 bool os::is_headless_jre() {
  4737     struct stat statbuf;
  4738     char buf[MAXPATHLEN];
  4739     char libmawtpath[MAXPATHLEN];
  4740     const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
  4741     const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
  4742     char *p;
  4744     // Get path to libjvm.so
  4745     os::jvm_path(buf, sizeof(buf));
  4747     // Get rid of libjvm.so
  4748     p = strrchr(buf, '/');
  4749     if (p == NULL) return false;
  4750     else *p = '\0';
  4752     // Get rid of client or server
  4753     p = strrchr(buf, '/');
  4754     if (p == NULL) return false;
  4755     else *p = '\0';
  4757     // check xawt/libmawt.so
  4758     strcpy(libmawtpath, buf);
  4759     strcat(libmawtpath, xawtstr);
  4760     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4762     // check libawt_xawt.so
  4763     strcpy(libmawtpath, buf);
  4764     strcat(libmawtpath, new_xawtstr);
  4765     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4767     return true;
  4770 // Get the default path to the core file
  4771 // Returns the length of the string
  4772 int os::get_core_path(char* buffer, size_t bufferSize) {
  4773   int n = jio_snprintf(buffer, bufferSize, "/cores");
  4775   // Truncate if theoretical string was longer than bufferSize
  4776   n = MIN2(n, (int)bufferSize);
  4778   return n;
  4781 #ifndef PRODUCT
  4782 void TestReserveMemorySpecial_test() {
  4783   // No tests available for this platform
  4785 #endif

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