src/os/bsd/vm/os_bsd.cpp

Thu, 13 Mar 2014 14:57:01 -0700

author
kvn
date
Thu, 13 Mar 2014 14:57:01 -0700
changeset 6513
bbfbe9b06038
parent 6472
2b8e28fdf503
parent 6326
d1621038becf
child 6518
62c54fcc0a35
permissions
-rw-r--r--

Merge

     1 /*
     2  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 // no precompiled headers
    26 #include "classfile/classLoader.hpp"
    27 #include "classfile/systemDictionary.hpp"
    28 #include "classfile/vmSymbols.hpp"
    29 #include "code/icBuffer.hpp"
    30 #include "code/vtableStubs.hpp"
    31 #include "compiler/compileBroker.hpp"
    32 #include "compiler/disassembler.hpp"
    33 #include "interpreter/interpreter.hpp"
    34 #include "jvm_bsd.h"
    35 #include "memory/allocation.inline.hpp"
    36 #include "memory/filemap.hpp"
    37 #include "mutex_bsd.inline.hpp"
    38 #include "oops/oop.inline.hpp"
    39 #include "os_share_bsd.hpp"
    40 #include "prims/jniFastGetField.hpp"
    41 #include "prims/jvm.h"
    42 #include "prims/jvm_misc.hpp"
    43 #include "runtime/arguments.hpp"
    44 #include "runtime/extendedPC.hpp"
    45 #include "runtime/globals.hpp"
    46 #include "runtime/interfaceSupport.hpp"
    47 #include "runtime/java.hpp"
    48 #include "runtime/javaCalls.hpp"
    49 #include "runtime/mutexLocker.hpp"
    50 #include "runtime/objectMonitor.hpp"
    51 #include "runtime/osThread.hpp"
    52 #include "runtime/perfMemory.hpp"
    53 #include "runtime/sharedRuntime.hpp"
    54 #include "runtime/statSampler.hpp"
    55 #include "runtime/stubRoutines.hpp"
    56 #include "runtime/thread.inline.hpp"
    57 #include "runtime/threadCritical.hpp"
    58 #include "runtime/timer.hpp"
    59 #include "services/attachListener.hpp"
    60 #include "services/memTracker.hpp"
    61 #include "services/runtimeService.hpp"
    62 #include "utilities/decoder.hpp"
    63 #include "utilities/defaultStream.hpp"
    64 #include "utilities/events.hpp"
    65 #include "utilities/growableArray.hpp"
    66 #include "utilities/vmError.hpp"
    68 // put OS-includes here
    69 # include <sys/types.h>
    70 # include <sys/mman.h>
    71 # include <sys/stat.h>
    72 # include <sys/select.h>
    73 # include <pthread.h>
    74 # include <signal.h>
    75 # include <errno.h>
    76 # include <dlfcn.h>
    77 # include <stdio.h>
    78 # include <unistd.h>
    79 # include <sys/resource.h>
    80 # include <pthread.h>
    81 # include <sys/stat.h>
    82 # include <sys/time.h>
    83 # include <sys/times.h>
    84 # include <sys/utsname.h>
    85 # include <sys/socket.h>
    86 # include <sys/wait.h>
    87 # include <time.h>
    88 # include <pwd.h>
    89 # include <poll.h>
    90 # include <semaphore.h>
    91 # include <fcntl.h>
    92 # include <string.h>
    93 # include <sys/param.h>
    94 # include <sys/sysctl.h>
    95 # include <sys/ipc.h>
    96 # include <sys/shm.h>
    97 #ifndef __APPLE__
    98 # include <link.h>
    99 #endif
   100 # include <stdint.h>
   101 # include <inttypes.h>
   102 # include <sys/ioctl.h>
   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 // available here means free
   163 julong os::Bsd::available_memory() {
   164   uint64_t available = physical_memory() >> 2;
   165 #ifdef __APPLE__
   166   mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
   167   vm_statistics64_data_t vmstat;
   168   kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
   169                                          (host_info64_t)&vmstat, &count);
   170   assert(kerr == KERN_SUCCESS,
   171          "host_statistics64 failed - check mach_host_self() and count");
   172   if (kerr == KERN_SUCCESS) {
   173     available = vmstat.free_count * os::vm_page_size();
   174   }
   175 #endif
   176   return available;
   177 }
   179 julong os::physical_memory() {
   180   return Bsd::physical_memory();
   181 }
   183 ////////////////////////////////////////////////////////////////////////////////
   184 // environment support
   186 bool os::getenv(const char* name, char* buf, int len) {
   187   const char* val = ::getenv(name);
   188   if (val != NULL && strlen(val) < (size_t)len) {
   189     strcpy(buf, val);
   190     return true;
   191   }
   192   if (len > 0) buf[0] = 0;  // return a null string
   193   return false;
   194 }
   197 // Return true if user is running as root.
   199 bool os::have_special_privileges() {
   200   static bool init = false;
   201   static bool privileges = false;
   202   if (!init) {
   203     privileges = (getuid() != geteuid()) || (getgid() != getegid());
   204     init = true;
   205   }
   206   return privileges;
   207 }
   211 // Cpu architecture string
   212 #if   defined(ZERO)
   213 static char cpu_arch[] = ZERO_LIBARCH;
   214 #elif defined(IA64)
   215 static char cpu_arch[] = "ia64";
   216 #elif defined(IA32)
   217 static char cpu_arch[] = "i386";
   218 #elif defined(AMD64)
   219 static char cpu_arch[] = "amd64";
   220 #elif defined(ARM)
   221 static char cpu_arch[] = "arm";
   222 #elif defined(PPC32)
   223 static char cpu_arch[] = "ppc";
   224 #elif defined(SPARC)
   225 #  ifdef _LP64
   226 static char cpu_arch[] = "sparcv9";
   227 #  else
   228 static char cpu_arch[] = "sparc";
   229 #  endif
   230 #else
   231 #error Add appropriate cpu_arch setting
   232 #endif
   234 // Compiler variant
   235 #ifdef COMPILER2
   236 #define COMPILER_VARIANT "server"
   237 #else
   238 #define COMPILER_VARIANT "client"
   239 #endif
   242 void os::Bsd::initialize_system_info() {
   243   int mib[2];
   244   size_t len;
   245   int cpu_val;
   246   julong mem_val;
   248   /* get processors count via hw.ncpus sysctl */
   249   mib[0] = CTL_HW;
   250   mib[1] = HW_NCPU;
   251   len = sizeof(cpu_val);
   252   if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
   253        assert(len == sizeof(cpu_val), "unexpected data size");
   254        set_processor_count(cpu_val);
   255   }
   256   else {
   257        set_processor_count(1);   // fallback
   258   }
   260   /* get physical memory via hw.memsize sysctl (hw.memsize is used
   261    * since it returns a 64 bit value)
   262    */
   263   mib[0] = CTL_HW;
   265 #if defined (HW_MEMSIZE) // Apple
   266   mib[1] = HW_MEMSIZE;
   267 #elif defined(HW_PHYSMEM) // Most of BSD
   268   mib[1] = HW_PHYSMEM;
   269 #elif defined(HW_REALMEM) // Old FreeBSD
   270   mib[1] = HW_REALMEM;
   271 #else
   272   #error No ways to get physmem
   273 #endif
   275   len = sizeof(mem_val);
   276   if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
   277        assert(len == sizeof(mem_val), "unexpected data size");
   278        _physical_memory = mem_val;
   279   } else {
   280        _physical_memory = 256*1024*1024;       // fallback (XXXBSD?)
   281   }
   283 #ifdef __OpenBSD__
   284   {
   285        // limit _physical_memory memory view on OpenBSD since
   286        // datasize rlimit restricts us anyway.
   287        struct rlimit limits;
   288        getrlimit(RLIMIT_DATA, &limits);
   289        _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
   290   }
   291 #endif
   292 }
   294 #ifdef __APPLE__
   295 static const char *get_home() {
   296   const char *home_dir = ::getenv("HOME");
   297   if ((home_dir == NULL) || (*home_dir == '\0')) {
   298     struct passwd *passwd_info = getpwuid(geteuid());
   299     if (passwd_info != NULL) {
   300       home_dir = passwd_info->pw_dir;
   301     }
   302   }
   304   return home_dir;
   305 }
   306 #endif
   308 void os::init_system_properties_values() {
   309 //  char arch[12];
   310 //  sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
   312   // The next steps are taken in the product version:
   313   //
   314   // Obtain the JAVA_HOME value from the location of libjvm.so.
   315   // This library should be located at:
   316   // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
   317   //
   318   // If "/jre/lib/" appears at the right place in the path, then we
   319   // assume libjvm.so is installed in a JDK and we use this path.
   320   //
   321   // Otherwise exit with message: "Could not create the Java virtual machine."
   322   //
   323   // The following extra steps are taken in the debugging version:
   324   //
   325   // If "/jre/lib/" does NOT appear at the right place in the path
   326   // instead of exit check for $JAVA_HOME environment variable.
   327   //
   328   // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
   329   // then we append a fake suffix "hotspot/libjvm.so" to this path so
   330   // it looks like libjvm.so is installed there
   331   // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
   332   //
   333   // Otherwise exit.
   334   //
   335   // Important note: if the location of libjvm.so changes this
   336   // code needs to be changed accordingly.
   338   // The next few definitions allow the code to be verbatim:
   339 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
   340 #define getenv(n) ::getenv(n)
   342 /*
   343  * See ld(1):
   344  *      The linker uses the following search paths to locate required
   345  *      shared libraries:
   346  *        1: ...
   347  *        ...
   348  *        7: The default directories, normally /lib and /usr/lib.
   349  */
   350 #ifndef DEFAULT_LIBPATH
   351 #define DEFAULT_LIBPATH "/lib:/usr/lib"
   352 #endif
   354 #define EXTENSIONS_DIR  "/lib/ext"
   355 #define ENDORSED_DIR    "/lib/endorsed"
   356 #define REG_DIR         "/usr/java/packages"
   358 #ifdef __APPLE__
   359 #define SYS_EXTENSIONS_DIR   "/Library/Java/Extensions"
   360 #define SYS_EXTENSIONS_DIRS  SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
   361         const char *user_home_dir = get_home();
   362         // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
   363         int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
   364             sizeof(SYS_EXTENSIONS_DIRS);
   365 #endif
   367   {
   368     /* sysclasspath, java_home, dll_dir */
   369     {
   370         char *home_path;
   371         char *dll_path;
   372         char *pslash;
   373         char buf[MAXPATHLEN];
   374         os::jvm_path(buf, sizeof(buf));
   376         // Found the full path to libjvm.so.
   377         // Now cut the path to <java_home>/jre if we can.
   378         *(strrchr(buf, '/')) = '\0';  /* get rid of /libjvm.so */
   379         pslash = strrchr(buf, '/');
   380         if (pslash != NULL)
   381             *pslash = '\0';           /* get rid of /{client|server|hotspot} */
   382         dll_path = malloc(strlen(buf) + 1);
   383         if (dll_path == NULL)
   384             return;
   385         strcpy(dll_path, buf);
   386         Arguments::set_dll_dir(dll_path);
   388         if (pslash != NULL) {
   389             pslash = strrchr(buf, '/');
   390             if (pslash != NULL) {
   391                 *pslash = '\0';       /* get rid of /<arch> (/lib on macosx) */
   392 #ifndef __APPLE__
   393                 pslash = strrchr(buf, '/');
   394                 if (pslash != NULL)
   395                     *pslash = '\0';   /* get rid of /lib */
   396 #endif
   397             }
   398         }
   400         home_path = malloc(strlen(buf) + 1);
   401         if (home_path == NULL)
   402             return;
   403         strcpy(home_path, buf);
   404         Arguments::set_java_home(home_path);
   406         if (!set_boot_path('/', ':'))
   407             return;
   408     }
   410     /*
   411      * Where to look for native libraries
   412      *
   413      * Note: Due to a legacy implementation, most of the library path
   414      * is set in the launcher.  This was to accomodate linking restrictions
   415      * on legacy Bsd implementations (which are no longer supported).
   416      * Eventually, all the library path setting will be done here.
   417      *
   418      * However, to prevent the proliferation of improperly built native
   419      * libraries, the new path component /usr/java/packages is added here.
   420      * Eventually, all the library path setting will be done here.
   421      */
   422     {
   423         char *ld_library_path;
   425         /*
   426          * Construct the invariant part of ld_library_path. Note that the
   427          * space for the colon and the trailing null are provided by the
   428          * nulls included by the sizeof operator (so actually we allocate
   429          * a byte more than necessary).
   430          */
   431 #ifdef __APPLE__
   432         ld_library_path = (char *) malloc(system_ext_size);
   433         sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
   434 #else
   435         ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
   436             strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
   437         sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
   438 #endif
   440         /*
   441          * Get the user setting of LD_LIBRARY_PATH, and prepended it.  It
   442          * should always exist (until the legacy problem cited above is
   443          * addressed).
   444          */
   445 #ifdef __APPLE__
   446         // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
   447         char *l = getenv("JAVA_LIBRARY_PATH");
   448         if (l != 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(l) + 1 + strlen(t) + 1);
   452             sprintf(ld_library_path, "%s:%s", l, t);
   453             free(t);
   454         }
   456         char *v = getenv("DYLD_LIBRARY_PATH");
   457 #else
   458         char *v = getenv("LD_LIBRARY_PATH");
   459 #endif
   460         if (v != NULL) {
   461             char *t = ld_library_path;
   462             /* That's +1 for the colon and +1 for the trailing '\0' */
   463             ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
   464             sprintf(ld_library_path, "%s:%s", v, t);
   465             free(t);
   466         }
   468 #ifdef __APPLE__
   469         // Apple's Java6 has "." at the beginning of java.library.path.
   470         // OpenJDK on Windows has "." at the end of java.library.path.
   471         // OpenJDK on Linux and Solaris don't have "." in java.library.path
   472         // at all. To ease the transition from Apple's Java6 to OpenJDK7,
   473         // "." is appended to the end of java.library.path. Yes, this
   474         // could cause a change in behavior, but Apple's Java6 behavior
   475         // can be achieved by putting "." at the beginning of the
   476         // JAVA_LIBRARY_PATH environment variable.
   477         {
   478             char *t = ld_library_path;
   479             // that's +3 for appending ":." and the trailing '\0'
   480             ld_library_path = (char *) malloc(strlen(t) + 3);
   481             sprintf(ld_library_path, "%s:%s", t, ".");
   482             free(t);
   483         }
   484 #endif
   486         Arguments::set_library_path(ld_library_path);
   487     }
   489     /*
   490      * Extensions directories.
   491      *
   492      * Note that the space for the colon and the trailing null are provided
   493      * by the nulls included by the sizeof operator (so actually one byte more
   494      * than necessary is allocated).
   495      */
   496     {
   497 #ifdef __APPLE__
   498         char *buf = malloc(strlen(Arguments::get_java_home()) +
   499             sizeof(EXTENSIONS_DIR) + system_ext_size);
   500         sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
   501             SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
   502 #else
   503         char *buf = malloc(strlen(Arguments::get_java_home()) +
   504             sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
   505         sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
   506             Arguments::get_java_home());
   507 #endif
   509         Arguments::set_ext_dirs(buf);
   510     }
   512     /* Endorsed standards default directory. */
   513     {
   514         char * buf;
   515         buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
   516         sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
   517         Arguments::set_endorsed_dirs(buf);
   518     }
   519   }
   521 #ifdef __APPLE__
   522 #undef SYS_EXTENSIONS_DIR
   523 #endif
   524 #undef malloc
   525 #undef getenv
   526 #undef EXTENSIONS_DIR
   527 #undef ENDORSED_DIR
   529   // Done
   530   return;
   531 }
   533 ////////////////////////////////////////////////////////////////////////////////
   534 // breakpoint support
   536 void os::breakpoint() {
   537   BREAKPOINT;
   538 }
   540 extern "C" void breakpoint() {
   541   // use debugger to set breakpoint here
   542 }
   544 ////////////////////////////////////////////////////////////////////////////////
   545 // signal support
   547 debug_only(static bool signal_sets_initialized = false);
   548 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
   550 bool os::Bsd::is_sig_ignored(int sig) {
   551       struct sigaction oact;
   552       sigaction(sig, (struct sigaction*)NULL, &oact);
   553       void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*,  oact.sa_sigaction)
   554                                      : CAST_FROM_FN_PTR(void*,  oact.sa_handler);
   555       if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
   556            return true;
   557       else
   558            return false;
   559 }
   561 void os::Bsd::signal_sets_init() {
   562   // Should also have an assertion stating we are still single-threaded.
   563   assert(!signal_sets_initialized, "Already initialized");
   564   // Fill in signals that are necessarily unblocked for all threads in
   565   // the VM. Currently, we unblock the following signals:
   566   // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
   567   //                         by -Xrs (=ReduceSignalUsage));
   568   // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
   569   // other threads. The "ReduceSignalUsage" boolean tells us not to alter
   570   // the dispositions or masks wrt these signals.
   571   // Programs embedding the VM that want to use the above signals for their
   572   // own purposes must, at this time, use the "-Xrs" option to prevent
   573   // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
   574   // (See bug 4345157, and other related bugs).
   575   // In reality, though, unblocking these signals is really a nop, since
   576   // these signals are not blocked by default.
   577   sigemptyset(&unblocked_sigs);
   578   sigemptyset(&allowdebug_blocked_sigs);
   579   sigaddset(&unblocked_sigs, SIGILL);
   580   sigaddset(&unblocked_sigs, SIGSEGV);
   581   sigaddset(&unblocked_sigs, SIGBUS);
   582   sigaddset(&unblocked_sigs, SIGFPE);
   583   sigaddset(&unblocked_sigs, SR_signum);
   585   if (!ReduceSignalUsage) {
   586    if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
   587       sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
   588       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
   589    }
   590    if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
   591       sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
   592       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
   593    }
   594    if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
   595       sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
   596       sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
   597    }
   598   }
   599   // Fill in signals that are blocked by all but the VM thread.
   600   sigemptyset(&vm_sigs);
   601   if (!ReduceSignalUsage)
   602     sigaddset(&vm_sigs, BREAK_SIGNAL);
   603   debug_only(signal_sets_initialized = true);
   605 }
   607 // These are signals that are unblocked while a thread is running Java.
   608 // (For some reason, they get blocked by default.)
   609 sigset_t* os::Bsd::unblocked_signals() {
   610   assert(signal_sets_initialized, "Not initialized");
   611   return &unblocked_sigs;
   612 }
   614 // These are the signals that are blocked while a (non-VM) thread is
   615 // running Java. Only the VM thread handles these signals.
   616 sigset_t* os::Bsd::vm_signals() {
   617   assert(signal_sets_initialized, "Not initialized");
   618   return &vm_sigs;
   619 }
   621 // These are signals that are blocked during cond_wait to allow debugger in
   622 sigset_t* os::Bsd::allowdebug_blocked_signals() {
   623   assert(signal_sets_initialized, "Not initialized");
   624   return &allowdebug_blocked_sigs;
   625 }
   627 void os::Bsd::hotspot_sigmask(Thread* thread) {
   629   //Save caller's signal mask before setting VM signal mask
   630   sigset_t caller_sigmask;
   631   pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
   633   OSThread* osthread = thread->osthread();
   634   osthread->set_caller_sigmask(caller_sigmask);
   636   pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
   638   if (!ReduceSignalUsage) {
   639     if (thread->is_VM_thread()) {
   640       // Only the VM thread handles BREAK_SIGNAL ...
   641       pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
   642     } else {
   643       // ... all other threads block BREAK_SIGNAL
   644       pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
   645     }
   646   }
   647 }
   650 //////////////////////////////////////////////////////////////////////////////
   651 // create new thread
   653 // check if it's safe to start a new thread
   654 static bool _thread_safety_check(Thread* thread) {
   655   return true;
   656 }
   658 #ifdef __APPLE__
   659 // library handle for calling objc_registerThreadWithCollector()
   660 // without static linking to the libobjc library
   661 #define OBJC_LIB "/usr/lib/libobjc.dylib"
   662 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
   663 typedef void (*objc_registerThreadWithCollector_t)();
   664 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
   665 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
   666 #endif
   668 #ifdef __APPLE__
   669 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
   670   // Additional thread_id used to correlate threads in SA
   671   thread_identifier_info_data_t     m_ident_info;
   672   mach_msg_type_number_t            count = THREAD_IDENTIFIER_INFO_COUNT;
   674   thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
   675               (thread_info_t) &m_ident_info, &count);
   677   return m_ident_info.thread_id;
   678 }
   679 #endif
   681 // Thread start routine for all newly created threads
   682 static void *java_start(Thread *thread) {
   683   // Try to randomize the cache line index of hot stack frames.
   684   // This helps when threads of the same stack traces evict each other's
   685   // cache lines. The threads can be either from the same JVM instance, or
   686   // from different JVM instances. The benefit is especially true for
   687   // processors with hyperthreading technology.
   688   static int counter = 0;
   689   int pid = os::current_process_id();
   690   alloca(((pid ^ counter++) & 7) * 128);
   692   ThreadLocalStorage::set_thread(thread);
   694   OSThread* osthread = thread->osthread();
   695   Monitor* sync = osthread->startThread_lock();
   697   // non floating stack BsdThreads needs extra check, see above
   698   if (!_thread_safety_check(thread)) {
   699     // notify parent thread
   700     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   701     osthread->set_state(ZOMBIE);
   702     sync->notify_all();
   703     return NULL;
   704   }
   706   osthread->set_thread_id(os::Bsd::gettid());
   708 #ifdef __APPLE__
   709   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
   710   guarantee(unique_thread_id != 0, "unique thread id was not found");
   711   osthread->set_unique_thread_id(unique_thread_id);
   712 #endif
   713   // initialize signal mask for this thread
   714   os::Bsd::hotspot_sigmask(thread);
   716   // initialize floating point control register
   717   os::Bsd::init_thread_fpu_state();
   719 #ifdef __APPLE__
   720   // register thread with objc gc
   721   if (objc_registerThreadWithCollectorFunction != NULL) {
   722     objc_registerThreadWithCollectorFunction();
   723   }
   724 #endif
   726   // handshaking with parent thread
   727   {
   728     MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
   730     // notify parent thread
   731     osthread->set_state(INITIALIZED);
   732     sync->notify_all();
   734     // wait until os::start_thread()
   735     while (osthread->get_state() == INITIALIZED) {
   736       sync->wait(Mutex::_no_safepoint_check_flag);
   737     }
   738   }
   740   // call one more level start routine
   741   thread->run();
   743   return 0;
   744 }
   746 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
   747   assert(thread->osthread() == NULL, "caller responsible");
   749   // Allocate the OSThread object
   750   OSThread* osthread = new OSThread(NULL, NULL);
   751   if (osthread == NULL) {
   752     return false;
   753   }
   755   // set the correct thread state
   756   osthread->set_thread_type(thr_type);
   758   // Initial state is ALLOCATED but not INITIALIZED
   759   osthread->set_state(ALLOCATED);
   761   thread->set_osthread(osthread);
   763   // init thread attributes
   764   pthread_attr_t attr;
   765   pthread_attr_init(&attr);
   766   pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
   768   // stack size
   769   if (os::Bsd::supports_variable_stack_size()) {
   770     // calculate stack size if it's not specified by caller
   771     if (stack_size == 0) {
   772       stack_size = os::Bsd::default_stack_size(thr_type);
   774       switch (thr_type) {
   775       case os::java_thread:
   776         // Java threads use ThreadStackSize which default value can be
   777         // changed with the flag -Xss
   778         assert (JavaThread::stack_size_at_create() > 0, "this should be set");
   779         stack_size = JavaThread::stack_size_at_create();
   780         break;
   781       case os::compiler_thread:
   782         if (CompilerThreadStackSize > 0) {
   783           stack_size = (size_t)(CompilerThreadStackSize * K);
   784           break;
   785         } // else fall through:
   786           // use VMThreadStackSize if CompilerThreadStackSize is not defined
   787       case os::vm_thread:
   788       case os::pgc_thread:
   789       case os::cgc_thread:
   790       case os::watcher_thread:
   791         if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
   792         break;
   793       }
   794     }
   796     stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
   797     pthread_attr_setstacksize(&attr, stack_size);
   798   } else {
   799     // let pthread_create() pick the default value.
   800   }
   802   ThreadState state;
   804   {
   805     pthread_t tid;
   806     int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
   808     pthread_attr_destroy(&attr);
   810     if (ret != 0) {
   811       if (PrintMiscellaneous && (Verbose || WizardMode)) {
   812         perror("pthread_create()");
   813       }
   814       // Need to clean up stuff we've allocated so far
   815       thread->set_osthread(NULL);
   816       delete osthread;
   817       return false;
   818     }
   820     // Store pthread info into the OSThread
   821     osthread->set_pthread_id(tid);
   823     // Wait until child thread is either initialized or aborted
   824     {
   825       Monitor* sync_with_child = osthread->startThread_lock();
   826       MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   827       while ((state = osthread->get_state()) == ALLOCATED) {
   828         sync_with_child->wait(Mutex::_no_safepoint_check_flag);
   829       }
   830     }
   832   }
   834   // Aborted due to thread limit being reached
   835   if (state == ZOMBIE) {
   836       thread->set_osthread(NULL);
   837       delete osthread;
   838       return false;
   839   }
   841   // The thread is returned suspended (in state INITIALIZED),
   842   // and is started higher up in the call chain
   843   assert(state == INITIALIZED, "race condition");
   844   return true;
   845 }
   847 /////////////////////////////////////////////////////////////////////////////
   848 // attach existing thread
   850 // bootstrap the main thread
   851 bool os::create_main_thread(JavaThread* thread) {
   852   assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
   853   return create_attached_thread(thread);
   854 }
   856 bool os::create_attached_thread(JavaThread* thread) {
   857 #ifdef ASSERT
   858     thread->verify_not_published();
   859 #endif
   861   // Allocate the OSThread object
   862   OSThread* osthread = new OSThread(NULL, NULL);
   864   if (osthread == NULL) {
   865     return false;
   866   }
   868   osthread->set_thread_id(os::Bsd::gettid());
   870   // Store pthread info into the OSThread
   871 #ifdef __APPLE__
   872   uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
   873   guarantee(unique_thread_id != 0, "just checking");
   874   osthread->set_unique_thread_id(unique_thread_id);
   875 #endif
   876   osthread->set_pthread_id(::pthread_self());
   878   // initialize floating point control register
   879   os::Bsd::init_thread_fpu_state();
   881   // Initial thread state is RUNNABLE
   882   osthread->set_state(RUNNABLE);
   884   thread->set_osthread(osthread);
   886   // initialize signal mask for this thread
   887   // and save the caller's signal mask
   888   os::Bsd::hotspot_sigmask(thread);
   890   return true;
   891 }
   893 void os::pd_start_thread(Thread* thread) {
   894   OSThread * osthread = thread->osthread();
   895   assert(osthread->get_state() != INITIALIZED, "just checking");
   896   Monitor* sync_with_child = osthread->startThread_lock();
   897   MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
   898   sync_with_child->notify();
   899 }
   901 // Free Bsd resources related to the OSThread
   902 void os::free_thread(OSThread* osthread) {
   903   assert(osthread != NULL, "osthread not set");
   905   if (Thread::current()->osthread() == osthread) {
   906     // Restore caller's signal mask
   907     sigset_t sigmask = osthread->caller_sigmask();
   908     pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
   909    }
   911   delete osthread;
   912 }
   914 //////////////////////////////////////////////////////////////////////////////
   915 // thread local storage
   917 int os::allocate_thread_local_storage() {
   918   pthread_key_t key;
   919   int rslt = pthread_key_create(&key, NULL);
   920   assert(rslt == 0, "cannot allocate thread local storage");
   921   return (int)key;
   922 }
   924 // Note: This is currently not used by VM, as we don't destroy TLS key
   925 // on VM exit.
   926 void os::free_thread_local_storage(int index) {
   927   int rslt = pthread_key_delete((pthread_key_t)index);
   928   assert(rslt == 0, "invalid index");
   929 }
   931 void os::thread_local_storage_at_put(int index, void* value) {
   932   int rslt = pthread_setspecific((pthread_key_t)index, value);
   933   assert(rslt == 0, "pthread_setspecific failed");
   934 }
   936 extern "C" Thread* get_thread() {
   937   return ThreadLocalStorage::thread();
   938 }
   941 ////////////////////////////////////////////////////////////////////////////////
   942 // time support
   944 // Time since start-up in seconds to a fine granularity.
   945 // Used by VMSelfDestructTimer and the MemProfiler.
   946 double os::elapsedTime() {
   948   return ((double)os::elapsed_counter()) / os::elapsed_frequency();
   949 }
   951 jlong os::elapsed_counter() {
   952   return javaTimeNanos() - initial_time_count;
   953 }
   955 jlong os::elapsed_frequency() {
   956   return NANOSECS_PER_SEC; // nanosecond resolution
   957 }
   959 bool os::supports_vtime() { return true; }
   960 bool os::enable_vtime()   { return false; }
   961 bool os::vtime_enabled()  { return false; }
   963 double os::elapsedVTime() {
   964   // better than nothing, but not much
   965   return elapsedTime();
   966 }
   968 jlong os::javaTimeMillis() {
   969   timeval time;
   970   int status = gettimeofday(&time, NULL);
   971   assert(status != -1, "bsd error");
   972   return jlong(time.tv_sec) * 1000  +  jlong(time.tv_usec / 1000);
   973 }
   975 #ifndef CLOCK_MONOTONIC
   976 #define CLOCK_MONOTONIC (1)
   977 #endif
   979 #ifdef __APPLE__
   980 void os::Bsd::clock_init() {
   981         // XXXDARWIN: Investigate replacement monotonic clock
   982 }
   983 #else
   984 void os::Bsd::clock_init() {
   985   struct timespec res;
   986   struct timespec tp;
   987   if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
   988       ::clock_gettime(CLOCK_MONOTONIC, &tp)  == 0) {
   989     // yes, monotonic clock is supported
   990     _clock_gettime = ::clock_gettime;
   991   }
   992 }
   993 #endif
   996 jlong os::javaTimeNanos() {
   997   if (Bsd::supports_monotonic_clock()) {
   998     struct timespec tp;
   999     int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
  1000     assert(status == 0, "gettime error");
  1001     jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
  1002     return result;
  1003   } else {
  1004     timeval time;
  1005     int status = gettimeofday(&time, NULL);
  1006     assert(status != -1, "bsd error");
  1007     jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
  1008     return 1000 * usecs;
  1012 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
  1013   if (Bsd::supports_monotonic_clock()) {
  1014     info_ptr->max_value = ALL_64_BITS;
  1016     // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
  1017     info_ptr->may_skip_backward = false;      // not subject to resetting or drifting
  1018     info_ptr->may_skip_forward = false;       // not subject to resetting or drifting
  1019   } else {
  1020     // gettimeofday - based on time in seconds since the Epoch thus does not wrap
  1021     info_ptr->max_value = ALL_64_BITS;
  1023     // gettimeofday is a real time clock so it skips
  1024     info_ptr->may_skip_backward = true;
  1025     info_ptr->may_skip_forward = true;
  1028   info_ptr->kind = JVMTI_TIMER_ELAPSED;                // elapsed not CPU time
  1031 // Return the real, user, and system times in seconds from an
  1032 // arbitrary fixed point in the past.
  1033 bool os::getTimesSecs(double* process_real_time,
  1034                       double* process_user_time,
  1035                       double* process_system_time) {
  1036   struct tms ticks;
  1037   clock_t real_ticks = times(&ticks);
  1039   if (real_ticks == (clock_t) (-1)) {
  1040     return false;
  1041   } else {
  1042     double ticks_per_second = (double) clock_tics_per_sec;
  1043     *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
  1044     *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
  1045     *process_real_time = ((double) real_ticks) / ticks_per_second;
  1047     return true;
  1052 char * os::local_time_string(char *buf, size_t buflen) {
  1053   struct tm t;
  1054   time_t long_time;
  1055   time(&long_time);
  1056   localtime_r(&long_time, &t);
  1057   jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
  1058                t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
  1059                t.tm_hour, t.tm_min, t.tm_sec);
  1060   return buf;
  1063 struct tm* os::localtime_pd(const time_t* clock, struct tm*  res) {
  1064   return localtime_r(clock, res);
  1067 ////////////////////////////////////////////////////////////////////////////////
  1068 // runtime exit support
  1070 // Note: os::shutdown() might be called very early during initialization, or
  1071 // called from signal handler. Before adding something to os::shutdown(), make
  1072 // sure it is async-safe and can handle partially initialized VM.
  1073 void os::shutdown() {
  1075   // allow PerfMemory to attempt cleanup of any persistent resources
  1076   perfMemory_exit();
  1078   // needs to remove object in file system
  1079   AttachListener::abort();
  1081   // flush buffered output, finish log files
  1082   ostream_abort();
  1084   // Check for abort hook
  1085   abort_hook_t abort_hook = Arguments::abort_hook();
  1086   if (abort_hook != NULL) {
  1087     abort_hook();
  1092 // Note: os::abort() might be called very early during initialization, or
  1093 // called from signal handler. Before adding something to os::abort(), make
  1094 // sure it is async-safe and can handle partially initialized VM.
  1095 void os::abort(bool dump_core) {
  1096   os::shutdown();
  1097   if (dump_core) {
  1098 #ifndef PRODUCT
  1099     fdStream out(defaultStream::output_fd());
  1100     out.print_raw("Current thread is ");
  1101     char buf[16];
  1102     jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
  1103     out.print_raw_cr(buf);
  1104     out.print_raw_cr("Dumping core ...");
  1105 #endif
  1106     ::abort(); // dump core
  1109   ::exit(1);
  1112 // Die immediately, no exit hook, no abort hook, no cleanup.
  1113 void os::die() {
  1114   // _exit() on BsdThreads only kills current thread
  1115   ::abort();
  1118 // unused on bsd for now.
  1119 void os::set_error_file(const char *logfile) {}
  1122 // This method is a copy of JDK's sysGetLastErrorString
  1123 // from src/solaris/hpi/src/system_md.c
  1125 size_t os::lasterror(char *buf, size_t len) {
  1127   if (errno == 0)  return 0;
  1129   const char *s = ::strerror(errno);
  1130   size_t n = ::strlen(s);
  1131   if (n >= len) {
  1132     n = len - 1;
  1134   ::strncpy(buf, s, n);
  1135   buf[n] = '\0';
  1136   return n;
  1139 // Information of current thread in variety of formats
  1140 pid_t os::Bsd::gettid() {
  1141   int retval = -1;
  1143 #ifdef __APPLE__ //XNU kernel
  1144   // despite the fact mach port is actually not a thread id use it
  1145   // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
  1146   retval = ::pthread_mach_thread_np(::pthread_self());
  1147   guarantee(retval != 0, "just checking");
  1148   return retval;
  1150 #elif __FreeBSD__
  1151   retval = syscall(SYS_thr_self);
  1152 #elif __OpenBSD__
  1153   retval = syscall(SYS_getthrid);
  1154 #elif __NetBSD__
  1155   retval = (pid_t) syscall(SYS__lwp_self);
  1156 #endif
  1158   if (retval == -1) {
  1159     return getpid();
  1163 intx os::current_thread_id() {
  1164 #ifdef __APPLE__
  1165   return (intx)::pthread_mach_thread_np(::pthread_self());
  1166 #else
  1167   return (intx)::pthread_self();
  1168 #endif
  1171 int os::current_process_id() {
  1173   // Under the old bsd thread library, bsd gives each thread
  1174   // its own process id. Because of this each thread will return
  1175   // a different pid if this method were to return the result
  1176   // of getpid(2). Bsd provides no api that returns the pid
  1177   // of the launcher thread for the vm. This implementation
  1178   // returns a unique pid, the pid of the launcher thread
  1179   // that starts the vm 'process'.
  1181   // Under the NPTL, getpid() returns the same pid as the
  1182   // launcher thread rather than a unique pid per thread.
  1183   // Use gettid() if you want the old pre NPTL behaviour.
  1185   // if you are looking for the result of a call to getpid() that
  1186   // returns a unique pid for the calling thread, then look at the
  1187   // OSThread::thread_id() method in osThread_bsd.hpp file
  1189   return (int)(_initial_pid ? _initial_pid : getpid());
  1192 // DLL functions
  1194 #define JNI_LIB_PREFIX "lib"
  1195 #ifdef __APPLE__
  1196 #define JNI_LIB_SUFFIX ".dylib"
  1197 #else
  1198 #define JNI_LIB_SUFFIX ".so"
  1199 #endif
  1201 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
  1203 // This must be hard coded because it's the system's temporary
  1204 // directory not the java application's temp directory, ala java.io.tmpdir.
  1205 #ifdef __APPLE__
  1206 // macosx has a secure per-user temporary directory
  1207 char temp_path_storage[PATH_MAX];
  1208 const char* os::get_temp_directory() {
  1209   static char *temp_path = NULL;
  1210   if (temp_path == NULL) {
  1211     int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
  1212     if (pathSize == 0 || pathSize > PATH_MAX) {
  1213       strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
  1215     temp_path = temp_path_storage;
  1217   return temp_path;
  1219 #else /* __APPLE__ */
  1220 const char* os::get_temp_directory() { return "/tmp"; }
  1221 #endif /* __APPLE__ */
  1223 static bool file_exists(const char* filename) {
  1224   struct stat statbuf;
  1225   if (filename == NULL || strlen(filename) == 0) {
  1226     return false;
  1228   return os::stat(filename, &statbuf) == 0;
  1231 bool os::dll_build_name(char* buffer, size_t buflen,
  1232                         const char* pname, const char* fname) {
  1233   bool retval = false;
  1234   // Copied from libhpi
  1235   const size_t pnamelen = pname ? strlen(pname) : 0;
  1237   // Return error on buffer overflow.
  1238   if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
  1239     return retval;
  1242   if (pnamelen == 0) {
  1243     snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
  1244     retval = true;
  1245   } else if (strchr(pname, *os::path_separator()) != NULL) {
  1246     int n;
  1247     char** pelements = split_path(pname, &n);
  1248     if (pelements == NULL) {
  1249       return false;
  1251     for (int i = 0 ; i < n ; i++) {
  1252       // Really shouldn't be NULL, but check can't hurt
  1253       if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
  1254         continue; // skip the empty path values
  1256       snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
  1257           pelements[i], fname);
  1258       if (file_exists(buffer)) {
  1259         retval = true;
  1260         break;
  1263     // release the storage
  1264     for (int i = 0 ; i < n ; i++) {
  1265       if (pelements[i] != NULL) {
  1266         FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
  1269     if (pelements != NULL) {
  1270       FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
  1272   } else {
  1273     snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
  1274     retval = true;
  1276   return retval;
  1279 // check if addr is inside libjvm.so
  1280 bool os::address_is_in_vm(address addr) {
  1281   static address libjvm_base_addr;
  1282   Dl_info dlinfo;
  1284   if (libjvm_base_addr == NULL) {
  1285     if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
  1286       libjvm_base_addr = (address)dlinfo.dli_fbase;
  1288     assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
  1291   if (dladdr((void *)addr, &dlinfo) != 0) {
  1292     if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
  1295   return false;
  1299 #define MACH_MAXSYMLEN 256
  1301 bool os::dll_address_to_function_name(address addr, char *buf,
  1302                                       int buflen, int *offset) {
  1303   // buf is not optional, but offset is optional
  1304   assert(buf != NULL, "sanity check");
  1306   Dl_info dlinfo;
  1307   char localbuf[MACH_MAXSYMLEN];
  1309   if (dladdr((void*)addr, &dlinfo) != 0) {
  1310     // see if we have a matching symbol
  1311     if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
  1312       if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
  1313         jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
  1315       if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
  1316       return true;
  1318     // no matching symbol so try for just file info
  1319     if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
  1320       if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
  1321                           buf, buflen, offset, dlinfo.dli_fname)) {
  1322          return true;
  1326     // Handle non-dynamic manually:
  1327     if (dlinfo.dli_fbase != NULL &&
  1328         Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
  1329                         dlinfo.dli_fbase)) {
  1330       if (!Decoder::demangle(localbuf, buf, buflen)) {
  1331         jio_snprintf(buf, buflen, "%s", localbuf);
  1333       return true;
  1336   buf[0] = '\0';
  1337   if (offset != NULL) *offset = -1;
  1338   return false;
  1341 // ported from solaris version
  1342 bool os::dll_address_to_library_name(address addr, char* buf,
  1343                                      int buflen, int* offset) {
  1344   // buf is not optional, but offset is optional
  1345   assert(buf != NULL, "sanity check");
  1347   Dl_info dlinfo;
  1349   if (dladdr((void*)addr, &dlinfo) != 0) {
  1350     if (dlinfo.dli_fname != NULL) {
  1351       jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
  1353     if (dlinfo.dli_fbase != NULL && offset != NULL) {
  1354       *offset = addr - (address)dlinfo.dli_fbase;
  1356     return true;
  1359   buf[0] = '\0';
  1360   if (offset) *offset = -1;
  1361   return false;
  1364 // Loads .dll/.so and
  1365 // in case of error it checks if .dll/.so was built for the
  1366 // same architecture as Hotspot is running on
  1368 #ifdef __APPLE__
  1369 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
  1370   void * result= ::dlopen(filename, RTLD_LAZY);
  1371   if (result != NULL) {
  1372     // Successful loading
  1373     return result;
  1376   // Read system error message into ebuf
  1377   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1378   ebuf[ebuflen-1]='\0';
  1380   return NULL;
  1382 #else
  1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
  1385   void * result= ::dlopen(filename, RTLD_LAZY);
  1386   if (result != NULL) {
  1387     // Successful loading
  1388     return result;
  1391   Elf32_Ehdr elf_head;
  1393   // Read system error message into ebuf
  1394   // It may or may not be overwritten below
  1395   ::strncpy(ebuf, ::dlerror(), ebuflen-1);
  1396   ebuf[ebuflen-1]='\0';
  1397   int diag_msg_max_length=ebuflen-strlen(ebuf);
  1398   char* diag_msg_buf=ebuf+strlen(ebuf);
  1400   if (diag_msg_max_length==0) {
  1401     // No more space in ebuf for additional diagnostics message
  1402     return NULL;
  1406   int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
  1408   if (file_descriptor < 0) {
  1409     // Can't open library, report dlerror() message
  1410     return NULL;
  1413   bool failed_to_read_elf_head=
  1414     (sizeof(elf_head)!=
  1415         (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
  1417   ::close(file_descriptor);
  1418   if (failed_to_read_elf_head) {
  1419     // file i/o error - report dlerror() msg
  1420     return NULL;
  1423   typedef struct {
  1424     Elf32_Half  code;         // Actual value as defined in elf.h
  1425     Elf32_Half  compat_class; // Compatibility of archs at VM's sense
  1426     char        elf_class;    // 32 or 64 bit
  1427     char        endianess;    // MSB or LSB
  1428     char*       name;         // String representation
  1429   } arch_t;
  1431   #ifndef EM_486
  1432   #define EM_486          6               /* Intel 80486 */
  1433   #endif
  1435   #ifndef EM_MIPS_RS3_LE
  1436   #define EM_MIPS_RS3_LE  10              /* MIPS */
  1437   #endif
  1439   #ifndef EM_PPC64
  1440   #define EM_PPC64        21              /* PowerPC64 */
  1441   #endif
  1443   #ifndef EM_S390
  1444   #define EM_S390         22              /* IBM System/390 */
  1445   #endif
  1447   #ifndef EM_IA_64
  1448   #define EM_IA_64        50              /* HP/Intel IA-64 */
  1449   #endif
  1451   #ifndef EM_X86_64
  1452   #define EM_X86_64       62              /* AMD x86-64 */
  1453   #endif
  1455   static const arch_t arch_array[]={
  1456     {EM_386,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1457     {EM_486,         EM_386,     ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
  1458     {EM_IA_64,       EM_IA_64,   ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
  1459     {EM_X86_64,      EM_X86_64,  ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
  1460     {EM_SPARC,       EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1461     {EM_SPARC32PLUS, EM_SPARC,   ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
  1462     {EM_SPARCV9,     EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
  1463     {EM_PPC,         EM_PPC,     ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
  1464     {EM_PPC64,       EM_PPC64,   ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
  1465     {EM_ARM,         EM_ARM,     ELFCLASS32,   ELFDATA2LSB, (char*)"ARM"},
  1466     {EM_S390,        EM_S390,    ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
  1467     {EM_ALPHA,       EM_ALPHA,   ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
  1468     {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
  1469     {EM_MIPS,        EM_MIPS,    ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
  1470     {EM_PARISC,      EM_PARISC,  ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
  1471     {EM_68K,         EM_68K,     ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
  1472   };
  1474   #if  (defined IA32)
  1475     static  Elf32_Half running_arch_code=EM_386;
  1476   #elif   (defined AMD64)
  1477     static  Elf32_Half running_arch_code=EM_X86_64;
  1478   #elif  (defined IA64)
  1479     static  Elf32_Half running_arch_code=EM_IA_64;
  1480   #elif  (defined __sparc) && (defined _LP64)
  1481     static  Elf32_Half running_arch_code=EM_SPARCV9;
  1482   #elif  (defined __sparc) && (!defined _LP64)
  1483     static  Elf32_Half running_arch_code=EM_SPARC;
  1484   #elif  (defined __powerpc64__)
  1485     static  Elf32_Half running_arch_code=EM_PPC64;
  1486   #elif  (defined __powerpc__)
  1487     static  Elf32_Half running_arch_code=EM_PPC;
  1488   #elif  (defined ARM)
  1489     static  Elf32_Half running_arch_code=EM_ARM;
  1490   #elif  (defined S390)
  1491     static  Elf32_Half running_arch_code=EM_S390;
  1492   #elif  (defined ALPHA)
  1493     static  Elf32_Half running_arch_code=EM_ALPHA;
  1494   #elif  (defined MIPSEL)
  1495     static  Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
  1496   #elif  (defined PARISC)
  1497     static  Elf32_Half running_arch_code=EM_PARISC;
  1498   #elif  (defined MIPS)
  1499     static  Elf32_Half running_arch_code=EM_MIPS;
  1500   #elif  (defined M68K)
  1501     static  Elf32_Half running_arch_code=EM_68K;
  1502   #else
  1503     #error Method os::dll_load requires that one of following is defined:\
  1504          IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
  1505   #endif
  1507   // Identify compatability class for VM's architecture and library's architecture
  1508   // Obtain string descriptions for architectures
  1510   arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
  1511   int running_arch_index=-1;
  1513   for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
  1514     if (running_arch_code == arch_array[i].code) {
  1515       running_arch_index    = i;
  1517     if (lib_arch.code == arch_array[i].code) {
  1518       lib_arch.compat_class = arch_array[i].compat_class;
  1519       lib_arch.name         = arch_array[i].name;
  1523   assert(running_arch_index != -1,
  1524     "Didn't find running architecture code (running_arch_code) in arch_array");
  1525   if (running_arch_index == -1) {
  1526     // Even though running architecture detection failed
  1527     // we may still continue with reporting dlerror() message
  1528     return NULL;
  1531   if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
  1532     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
  1533     return NULL;
  1536 #ifndef S390
  1537   if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
  1538     ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
  1539     return NULL;
  1541 #endif // !S390
  1543   if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
  1544     if ( lib_arch.name!=NULL ) {
  1545       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1546         " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
  1547         lib_arch.name, arch_array[running_arch_index].name);
  1548     } else {
  1549       ::snprintf(diag_msg_buf, diag_msg_max_length-1,
  1550       " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
  1551         lib_arch.code,
  1552         arch_array[running_arch_index].name);
  1556   return NULL;
  1558 #endif /* !__APPLE__ */
  1560 void* os::get_default_process_handle() {
  1561 #ifdef __APPLE__
  1562   // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
  1563   // to avoid finding unexpected symbols on second (or later)
  1564   // loads of a library.
  1565   return (void*)::dlopen(NULL, RTLD_FIRST);
  1566 #else
  1567   return (void*)::dlopen(NULL, RTLD_LAZY);
  1568 #endif
  1571 // XXX: Do we need a lock around this as per Linux?
  1572 void* os::dll_lookup(void* handle, const char* name) {
  1573   return dlsym(handle, name);
  1577 static bool _print_ascii_file(const char* filename, outputStream* st) {
  1578   int fd = ::open(filename, O_RDONLY);
  1579   if (fd == -1) {
  1580      return false;
  1583   char buf[32];
  1584   int bytes;
  1585   while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
  1586     st->print_raw(buf, bytes);
  1589   ::close(fd);
  1591   return true;
  1594 void os::print_dll_info(outputStream *st) {
  1595   st->print_cr("Dynamic libraries:");
  1596 #ifdef RTLD_DI_LINKMAP
  1597   Dl_info dli;
  1598   void *handle;
  1599   Link_map *map;
  1600   Link_map *p;
  1602   if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
  1603       dli.dli_fname == NULL) {
  1604     st->print_cr("Error: Cannot print dynamic libraries.");
  1605     return;
  1607   handle = dlopen(dli.dli_fname, RTLD_LAZY);
  1608   if (handle == NULL) {
  1609     st->print_cr("Error: Cannot print dynamic libraries.");
  1610     return;
  1612   dlinfo(handle, RTLD_DI_LINKMAP, &map);
  1613   if (map == NULL) {
  1614     st->print_cr("Error: Cannot print dynamic libraries.");
  1615     return;
  1618   while (map->l_prev != NULL)
  1619     map = map->l_prev;
  1621   while (map != NULL) {
  1622     st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
  1623     map = map->l_next;
  1626   dlclose(handle);
  1627 #elif defined(__APPLE__)
  1628   uint32_t count;
  1629   uint32_t i;
  1631   count = _dyld_image_count();
  1632   for (i = 1; i < count; i++) {
  1633     const char *name = _dyld_get_image_name(i);
  1634     intptr_t slide = _dyld_get_image_vmaddr_slide(i);
  1635     st->print_cr(PTR_FORMAT " \t%s", slide, name);
  1637 #else
  1638   st->print_cr("Error: Cannot print dynamic libraries.");
  1639 #endif
  1642 void os::print_os_info_brief(outputStream* st) {
  1643   st->print("Bsd");
  1645   os::Posix::print_uname_info(st);
  1648 void os::print_os_info(outputStream* st) {
  1649   st->print("OS:");
  1650   st->print("Bsd");
  1652   os::Posix::print_uname_info(st);
  1654   os::Posix::print_rlimit_info(st);
  1656   os::Posix::print_load_average(st);
  1659 void os::pd_print_cpu_info(outputStream* st) {
  1660   // Nothing to do for now.
  1663 void os::print_memory_info(outputStream* st) {
  1665   st->print("Memory:");
  1666   st->print(" %dk page", os::vm_page_size()>>10);
  1668   st->print(", physical " UINT64_FORMAT "k",
  1669             os::physical_memory() >> 10);
  1670   st->print("(" UINT64_FORMAT "k free)",
  1671             os::available_memory() >> 10);
  1672   st->cr();
  1674   // meminfo
  1675   st->print("\n/proc/meminfo:\n");
  1676   _print_ascii_file("/proc/meminfo", st);
  1677   st->cr();
  1680 void os::print_siginfo(outputStream* st, void* siginfo) {
  1681   const siginfo_t* si = (const siginfo_t*)siginfo;
  1683   os::Posix::print_siginfo_brief(st, si);
  1685   if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
  1686       UseSharedSpaces) {
  1687     FileMapInfo* mapinfo = FileMapInfo::current_info();
  1688     if (mapinfo->is_in_shared_space(si->si_addr)) {
  1689       st->print("\n\nError accessing class data sharing archive."   \
  1690                 " Mapped file inaccessible during execution, "      \
  1691                 " possible disk/network problem.");
  1694   st->cr();
  1698 static void print_signal_handler(outputStream* st, int sig,
  1699                                  char* buf, size_t buflen);
  1701 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
  1702   st->print_cr("Signal Handlers:");
  1703   print_signal_handler(st, SIGSEGV, buf, buflen);
  1704   print_signal_handler(st, SIGBUS , buf, buflen);
  1705   print_signal_handler(st, SIGFPE , buf, buflen);
  1706   print_signal_handler(st, SIGPIPE, buf, buflen);
  1707   print_signal_handler(st, SIGXFSZ, buf, buflen);
  1708   print_signal_handler(st, SIGILL , buf, buflen);
  1709   print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
  1710   print_signal_handler(st, SR_signum, buf, buflen);
  1711   print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
  1712   print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
  1713   print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
  1714   print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
  1717 static char saved_jvm_path[MAXPATHLEN] = {0};
  1719 // Find the full path to the current module, libjvm
  1720 void os::jvm_path(char *buf, jint buflen) {
  1721   // Error checking.
  1722   if (buflen < MAXPATHLEN) {
  1723     assert(false, "must use a large-enough buffer");
  1724     buf[0] = '\0';
  1725     return;
  1727   // Lazy resolve the path to current module.
  1728   if (saved_jvm_path[0] != 0) {
  1729     strcpy(buf, saved_jvm_path);
  1730     return;
  1733   char dli_fname[MAXPATHLEN];
  1734   bool ret = dll_address_to_library_name(
  1735                 CAST_FROM_FN_PTR(address, os::jvm_path),
  1736                 dli_fname, sizeof(dli_fname), NULL);
  1737   assert(ret, "cannot locate libjvm");
  1738   char *rp = NULL;
  1739   if (ret && dli_fname[0] != '\0') {
  1740     rp = realpath(dli_fname, buf);
  1742   if (rp == NULL)
  1743     return;
  1745   if (Arguments::created_by_gamma_launcher()) {
  1746     // Support for the gamma launcher.  Typical value for buf is
  1747     // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm".  If "/jre/lib/" appears at
  1748     // the right place in the string, then assume we are installed in a JDK and
  1749     // we're done.  Otherwise, check for a JAVA_HOME environment variable and
  1750     // construct a path to the JVM being overridden.
  1752     const char *p = buf + strlen(buf) - 1;
  1753     for (int count = 0; p > buf && count < 5; ++count) {
  1754       for (--p; p > buf && *p != '/'; --p)
  1755         /* empty */ ;
  1758     if (strncmp(p, "/jre/lib/", 9) != 0) {
  1759       // Look for JAVA_HOME in the environment.
  1760       char* java_home_var = ::getenv("JAVA_HOME");
  1761       if (java_home_var != NULL && java_home_var[0] != 0) {
  1762         char* jrelib_p;
  1763         int len;
  1765         // Check the current module name "libjvm"
  1766         p = strrchr(buf, '/');
  1767         assert(strstr(p, "/libjvm") == p, "invalid library name");
  1769         rp = realpath(java_home_var, buf);
  1770         if (rp == NULL)
  1771           return;
  1773         // determine if this is a legacy image or modules image
  1774         // modules image doesn't have "jre" subdirectory
  1775         len = strlen(buf);
  1776         jrelib_p = buf + len;
  1778         // Add the appropriate library subdir
  1779         snprintf(jrelib_p, buflen-len, "/jre/lib");
  1780         if (0 != access(buf, F_OK)) {
  1781           snprintf(jrelib_p, buflen-len, "/lib");
  1784         // Add the appropriate client or server subdir
  1785         len = strlen(buf);
  1786         jrelib_p = buf + len;
  1787         snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
  1788         if (0 != access(buf, F_OK)) {
  1789           snprintf(jrelib_p, buflen-len, "");
  1792         // If the path exists within JAVA_HOME, add the JVM library name
  1793         // to complete the path to JVM being overridden.  Otherwise fallback
  1794         // to the path to the current library.
  1795         if (0 == access(buf, F_OK)) {
  1796           // Use current module name "libjvm"
  1797           len = strlen(buf);
  1798           snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
  1799         } else {
  1800           // Fall back to path of current library
  1801           rp = realpath(dli_fname, buf);
  1802           if (rp == NULL)
  1803             return;
  1809   strcpy(saved_jvm_path, buf);
  1812 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
  1813   // no prefix required, not even "_"
  1816 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
  1817   // no suffix required
  1820 ////////////////////////////////////////////////////////////////////////////////
  1821 // sun.misc.Signal support
  1823 static volatile jint sigint_count = 0;
  1825 static void
  1826 UserHandler(int sig, void *siginfo, void *context) {
  1827   // 4511530 - sem_post is serialized and handled by the manager thread. When
  1828   // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
  1829   // don't want to flood the manager thread with sem_post requests.
  1830   if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
  1831       return;
  1833   // Ctrl-C is pressed during error reporting, likely because the error
  1834   // handler fails to abort. Let VM die immediately.
  1835   if (sig == SIGINT && is_error_reported()) {
  1836      os::die();
  1839   os::signal_notify(sig);
  1842 void* os::user_handler() {
  1843   return CAST_FROM_FN_PTR(void*, UserHandler);
  1846 extern "C" {
  1847   typedef void (*sa_handler_t)(int);
  1848   typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
  1851 void* os::signal(int signal_number, void* handler) {
  1852   struct sigaction sigAct, oldSigAct;
  1854   sigfillset(&(sigAct.sa_mask));
  1855   sigAct.sa_flags   = SA_RESTART|SA_SIGINFO;
  1856   sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
  1858   if (sigaction(signal_number, &sigAct, &oldSigAct)) {
  1859     // -1 means registration failed
  1860     return (void *)-1;
  1863   return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
  1866 void os::signal_raise(int signal_number) {
  1867   ::raise(signal_number);
  1870 /*
  1871  * The following code is moved from os.cpp for making this
  1872  * code platform specific, which it is by its very nature.
  1873  */
  1875 // Will be modified when max signal is changed to be dynamic
  1876 int os::sigexitnum_pd() {
  1877   return NSIG;
  1880 // a counter for each possible signal value
  1881 static volatile jint pending_signals[NSIG+1] = { 0 };
  1883 // Bsd(POSIX) specific hand shaking semaphore.
  1884 #ifdef __APPLE__
  1885 typedef semaphore_t os_semaphore_t;
  1886 #define SEM_INIT(sem, value)    semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
  1887 #define SEM_WAIT(sem)           semaphore_wait(sem)
  1888 #define SEM_POST(sem)           semaphore_signal(sem)
  1889 #define SEM_DESTROY(sem)        semaphore_destroy(mach_task_self(), sem)
  1890 #else
  1891 typedef sem_t os_semaphore_t;
  1892 #define SEM_INIT(sem, value)    sem_init(&sem, 0, value)
  1893 #define SEM_WAIT(sem)           sem_wait(&sem)
  1894 #define SEM_POST(sem)           sem_post(&sem)
  1895 #define SEM_DESTROY(sem)        sem_destroy(&sem)
  1896 #endif
  1898 class Semaphore : public StackObj {
  1899   public:
  1900     Semaphore();
  1901     ~Semaphore();
  1902     void signal();
  1903     void wait();
  1904     bool trywait();
  1905     bool timedwait(unsigned int sec, int nsec);
  1906   private:
  1907     jlong currenttime() const;
  1908     os_semaphore_t _semaphore;
  1909 };
  1911 Semaphore::Semaphore() : _semaphore(0) {
  1912   SEM_INIT(_semaphore, 0);
  1915 Semaphore::~Semaphore() {
  1916   SEM_DESTROY(_semaphore);
  1919 void Semaphore::signal() {
  1920   SEM_POST(_semaphore);
  1923 void Semaphore::wait() {
  1924   SEM_WAIT(_semaphore);
  1927 jlong Semaphore::currenttime() const {
  1928     struct timeval tv;
  1929     gettimeofday(&tv, NULL);
  1930     return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
  1933 #ifdef __APPLE__
  1934 bool Semaphore::trywait() {
  1935   return timedwait(0, 0);
  1938 bool Semaphore::timedwait(unsigned int sec, int nsec) {
  1939   kern_return_t kr = KERN_ABORTED;
  1940   mach_timespec_t waitspec;
  1941   waitspec.tv_sec = sec;
  1942   waitspec.tv_nsec = nsec;
  1944   jlong starttime = currenttime();
  1946   kr = semaphore_timedwait(_semaphore, waitspec);
  1947   while (kr == KERN_ABORTED) {
  1948     jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
  1950     jlong current = currenttime();
  1951     jlong passedtime = current - starttime;
  1953     if (passedtime >= totalwait) {
  1954       waitspec.tv_sec = 0;
  1955       waitspec.tv_nsec = 0;
  1956     } else {
  1957       jlong waittime = totalwait - (current - starttime);
  1958       waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
  1959       waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
  1962     kr = semaphore_timedwait(_semaphore, waitspec);
  1965   return kr == KERN_SUCCESS;
  1968 #else
  1970 bool Semaphore::trywait() {
  1971   return sem_trywait(&_semaphore) == 0;
  1974 bool Semaphore::timedwait(unsigned int sec, int nsec) {
  1975   struct timespec ts;
  1976   unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
  1978   while (1) {
  1979     int result = sem_timedwait(&_semaphore, &ts);
  1980     if (result == 0) {
  1981       return true;
  1982     } else if (errno == EINTR) {
  1983       continue;
  1984     } else if (errno == ETIMEDOUT) {
  1985       return false;
  1986     } else {
  1987       return false;
  1992 #endif // __APPLE__
  1994 static os_semaphore_t sig_sem;
  1995 static Semaphore sr_semaphore;
  1997 void os::signal_init_pd() {
  1998   // Initialize signal structures
  1999   ::memset((void*)pending_signals, 0, sizeof(pending_signals));
  2001   // Initialize signal semaphore
  2002   ::SEM_INIT(sig_sem, 0);
  2005 void os::signal_notify(int sig) {
  2006   Atomic::inc(&pending_signals[sig]);
  2007   ::SEM_POST(sig_sem);
  2010 static int check_pending_signals(bool wait) {
  2011   Atomic::store(0, &sigint_count);
  2012   for (;;) {
  2013     for (int i = 0; i < NSIG + 1; i++) {
  2014       jint n = pending_signals[i];
  2015       if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
  2016         return i;
  2019     if (!wait) {
  2020       return -1;
  2022     JavaThread *thread = JavaThread::current();
  2023     ThreadBlockInVM tbivm(thread);
  2025     bool threadIsSuspended;
  2026     do {
  2027       thread->set_suspend_equivalent();
  2028       // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  2029       ::SEM_WAIT(sig_sem);
  2031       // were we externally suspended while we were waiting?
  2032       threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
  2033       if (threadIsSuspended) {
  2034         //
  2035         // The semaphore has been incremented, but while we were waiting
  2036         // another thread suspended us. We don't want to continue running
  2037         // while suspended because that would surprise the thread that
  2038         // suspended us.
  2039         //
  2040         ::SEM_POST(sig_sem);
  2042         thread->java_suspend_self();
  2044     } while (threadIsSuspended);
  2048 int os::signal_lookup() {
  2049   return check_pending_signals(false);
  2052 int os::signal_wait() {
  2053   return check_pending_signals(true);
  2056 ////////////////////////////////////////////////////////////////////////////////
  2057 // Virtual Memory
  2059 int os::vm_page_size() {
  2060   // Seems redundant as all get out
  2061   assert(os::Bsd::page_size() != -1, "must call os::init");
  2062   return os::Bsd::page_size();
  2065 // Solaris allocates memory by pages.
  2066 int os::vm_allocation_granularity() {
  2067   assert(os::Bsd::page_size() != -1, "must call os::init");
  2068   return os::Bsd::page_size();
  2071 // Rationale behind this function:
  2072 //  current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
  2073 //  mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
  2074 //  samples for JITted code. Here we create private executable mapping over the code cache
  2075 //  and then we can use standard (well, almost, as mapping can change) way to provide
  2076 //  info for the reporting script by storing timestamp and location of symbol
  2077 void bsd_wrap_code(char* base, size_t size) {
  2078   static volatile jint cnt = 0;
  2080   if (!UseOprofile) {
  2081     return;
  2084   char buf[PATH_MAX + 1];
  2085   int num = Atomic::add(1, &cnt);
  2087   snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
  2088            os::get_temp_directory(), os::current_process_id(), num);
  2089   unlink(buf);
  2091   int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
  2093   if (fd != -1) {
  2094     off_t rv = ::lseek(fd, size-2, SEEK_SET);
  2095     if (rv != (off_t)-1) {
  2096       if (::write(fd, "", 1) == 1) {
  2097         mmap(base, size,
  2098              PROT_READ|PROT_WRITE|PROT_EXEC,
  2099              MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
  2102     ::close(fd);
  2103     unlink(buf);
  2107 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
  2108                                     int err) {
  2109   warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
  2110           ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
  2111           strerror(err), err);
  2114 // NOTE: Bsd kernel does not really reserve the pages for us.
  2115 //       All it does is to check if there are enough free pages
  2116 //       left at the time of mmap(). This could be a potential
  2117 //       problem.
  2118 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
  2119   int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
  2120 #ifdef __OpenBSD__
  2121   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  2122   if (::mprotect(addr, size, prot) == 0) {
  2123     return true;
  2125 #else
  2126   uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
  2127                                    MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
  2128   if (res != (uintptr_t) MAP_FAILED) {
  2129     return true;
  2131 #endif
  2133   // Warn about any commit errors we see in non-product builds just
  2134   // in case mmap() doesn't work as described on the man page.
  2135   NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
  2137   return false;
  2140 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
  2141                        bool exec) {
  2142   // alignment_hint is ignored on this OS
  2143   return pd_commit_memory(addr, size, exec);
  2146 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
  2147                                   const char* mesg) {
  2148   assert(mesg != NULL, "mesg must be specified");
  2149   if (!pd_commit_memory(addr, size, exec)) {
  2150     // add extra info in product mode for vm_exit_out_of_memory():
  2151     PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
  2152     vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
  2156 void os::pd_commit_memory_or_exit(char* addr, size_t size,
  2157                                   size_t alignment_hint, bool exec,
  2158                                   const char* mesg) {
  2159   // alignment_hint is ignored on this OS
  2160   pd_commit_memory_or_exit(addr, size, exec, mesg);
  2163 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2166 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
  2167   ::madvise(addr, bytes, MADV_DONTNEED);
  2170 void os::numa_make_global(char *addr, size_t bytes) {
  2173 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
  2176 bool os::numa_topology_changed()   { return false; }
  2178 size_t os::numa_get_groups_num() {
  2179   return 1;
  2182 int os::numa_get_group_id() {
  2183   return 0;
  2186 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
  2187   if (size > 0) {
  2188     ids[0] = 0;
  2189     return 1;
  2191   return 0;
  2194 bool os::get_page_info(char *start, page_info* info) {
  2195   return false;
  2198 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
  2199   return end;
  2203 bool os::pd_uncommit_memory(char* addr, size_t size) {
  2204 #ifdef __OpenBSD__
  2205   // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
  2206   return ::mprotect(addr, size, PROT_NONE) == 0;
  2207 #else
  2208   uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
  2209                 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
  2210   return res  != (uintptr_t) MAP_FAILED;
  2211 #endif
  2214 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
  2215   return os::commit_memory(addr, size, !ExecMem);
  2218 // If this is a growable mapping, remove the guard pages entirely by
  2219 // munmap()ping them.  If not, just call uncommit_memory().
  2220 bool os::remove_stack_guard_pages(char* addr, size_t size) {
  2221   return os::uncommit_memory(addr, size);
  2224 static address _highest_vm_reserved_address = NULL;
  2226 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
  2227 // at 'requested_addr'. If there are existing memory mappings at the same
  2228 // location, however, they will be overwritten. If 'fixed' is false,
  2229 // 'requested_addr' is only treated as a hint, the return value may or
  2230 // may not start from the requested address. Unlike Bsd mmap(), this
  2231 // function returns NULL to indicate failure.
  2232 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
  2233   char * addr;
  2234   int flags;
  2236   flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
  2237   if (fixed) {
  2238     assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
  2239     flags |= MAP_FIXED;
  2242   // Map reserved/uncommitted pages PROT_NONE so we fail early if we
  2243   // touch an uncommitted page. Otherwise, the read/write might
  2244   // succeed if we have enough swap space to back the physical page.
  2245   addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
  2246                        flags, -1, 0);
  2248   if (addr != MAP_FAILED) {
  2249     // anon_mmap() should only get called during VM initialization,
  2250     // don't need lock (actually we can skip locking even it can be called
  2251     // from multiple threads, because _highest_vm_reserved_address is just a
  2252     // hint about the upper limit of non-stack memory regions.)
  2253     if ((address)addr + bytes > _highest_vm_reserved_address) {
  2254       _highest_vm_reserved_address = (address)addr + bytes;
  2258   return addr == MAP_FAILED ? NULL : addr;
  2261 // Don't update _highest_vm_reserved_address, because there might be memory
  2262 // regions above addr + size. If so, releasing a memory region only creates
  2263 // a hole in the address space, it doesn't help prevent heap-stack collision.
  2264 //
  2265 static int anon_munmap(char * addr, size_t size) {
  2266   return ::munmap(addr, size) == 0;
  2269 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
  2270                          size_t alignment_hint) {
  2271   return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
  2274 bool os::pd_release_memory(char* addr, size_t size) {
  2275   return anon_munmap(addr, size);
  2278 static bool bsd_mprotect(char* addr, size_t size, int prot) {
  2279   // Bsd wants the mprotect address argument to be page aligned.
  2280   char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
  2282   // According to SUSv3, mprotect() should only be used with mappings
  2283   // established by mmap(), and mmap() always maps whole pages. Unaligned
  2284   // 'addr' likely indicates problem in the VM (e.g. trying to change
  2285   // protection of malloc'ed or statically allocated memory). Check the
  2286   // caller if you hit this assert.
  2287   assert(addr == bottom, "sanity check");
  2289   size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
  2290   return ::mprotect(bottom, size, prot) == 0;
  2293 // Set protections specified
  2294 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
  2295                         bool is_committed) {
  2296   unsigned int p = 0;
  2297   switch (prot) {
  2298   case MEM_PROT_NONE: p = PROT_NONE; break;
  2299   case MEM_PROT_READ: p = PROT_READ; break;
  2300   case MEM_PROT_RW:   p = PROT_READ|PROT_WRITE; break;
  2301   case MEM_PROT_RWX:  p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
  2302   default:
  2303     ShouldNotReachHere();
  2305   // is_committed is unused.
  2306   return bsd_mprotect(addr, bytes, p);
  2309 bool os::guard_memory(char* addr, size_t size) {
  2310   return bsd_mprotect(addr, size, PROT_NONE);
  2313 bool os::unguard_memory(char* addr, size_t size) {
  2314   return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
  2317 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
  2318   return false;
  2321 // Large page support
  2323 static size_t _large_page_size = 0;
  2325 void os::large_page_init() {
  2329 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
  2330   fatal("This code is not used or maintained.");
  2332   // "exec" is passed in but not used.  Creating the shared image for
  2333   // the code cache doesn't have an SHM_X executable permission to check.
  2334   assert(UseLargePages && UseSHM, "only for SHM large pages");
  2336   key_t key = IPC_PRIVATE;
  2337   char *addr;
  2339   bool warn_on_failure = UseLargePages &&
  2340                         (!FLAG_IS_DEFAULT(UseLargePages) ||
  2341                          !FLAG_IS_DEFAULT(LargePageSizeInBytes)
  2342                         );
  2343   char msg[128];
  2345   // Create a large shared memory region to attach to based on size.
  2346   // Currently, size is the total size of the heap
  2347   int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
  2348   if (shmid == -1) {
  2349      // Possible reasons for shmget failure:
  2350      // 1. shmmax is too small for Java heap.
  2351      //    > check shmmax value: cat /proc/sys/kernel/shmmax
  2352      //    > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
  2353      // 2. not enough large page memory.
  2354      //    > check available large pages: cat /proc/meminfo
  2355      //    > increase amount of large pages:
  2356      //          echo new_value > /proc/sys/vm/nr_hugepages
  2357      //      Note 1: different Bsd may use different name for this property,
  2358      //            e.g. on Redhat AS-3 it is "hugetlb_pool".
  2359      //      Note 2: it's possible there's enough physical memory available but
  2360      //            they are so fragmented after a long run that they can't
  2361      //            coalesce into large pages. Try to reserve large pages when
  2362      //            the system is still "fresh".
  2363      if (warn_on_failure) {
  2364        jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
  2365        warning(msg);
  2367      return NULL;
  2370   // attach to the region
  2371   addr = (char*)shmat(shmid, req_addr, 0);
  2372   int err = errno;
  2374   // Remove shmid. If shmat() is successful, the actual shared memory segment
  2375   // will be deleted when it's detached by shmdt() or when the process
  2376   // terminates. If shmat() is not successful this will remove the shared
  2377   // segment immediately.
  2378   shmctl(shmid, IPC_RMID, NULL);
  2380   if ((intptr_t)addr == -1) {
  2381      if (warn_on_failure) {
  2382        jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
  2383        warning(msg);
  2385      return NULL;
  2388   // The memory is committed
  2389   MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
  2391   return addr;
  2394 bool os::release_memory_special(char* base, size_t bytes) {
  2395   MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
  2396   // detaching the SHM segment will also delete it, see reserve_memory_special()
  2397   int rslt = shmdt(base);
  2398   if (rslt == 0) {
  2399     tkr.record((address)base, bytes);
  2400     return true;
  2401   } else {
  2402     tkr.discard();
  2403     return false;
  2408 size_t os::large_page_size() {
  2409   return _large_page_size;
  2412 // HugeTLBFS allows application to commit large page memory on demand;
  2413 // with SysV SHM the entire memory region must be allocated as shared
  2414 // memory.
  2415 bool os::can_commit_large_page_memory() {
  2416   return UseHugeTLBFS;
  2419 bool os::can_execute_large_page_memory() {
  2420   return UseHugeTLBFS;
  2423 // Reserve memory at an arbitrary address, only if that area is
  2424 // available (and not reserved for something else).
  2426 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
  2427   const int max_tries = 10;
  2428   char* base[max_tries];
  2429   size_t size[max_tries];
  2430   const size_t gap = 0x000000;
  2432   // Assert only that the size is a multiple of the page size, since
  2433   // that's all that mmap requires, and since that's all we really know
  2434   // about at this low abstraction level.  If we need higher alignment,
  2435   // we can either pass an alignment to this method or verify alignment
  2436   // in one of the methods further up the call chain.  See bug 5044738.
  2437   assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
  2439   // Repeatedly allocate blocks until the block is allocated at the
  2440   // right spot. Give up after max_tries. Note that reserve_memory() will
  2441   // automatically update _highest_vm_reserved_address if the call is
  2442   // successful. The variable tracks the highest memory address every reserved
  2443   // by JVM. It is used to detect heap-stack collision if running with
  2444   // fixed-stack BsdThreads. Because here we may attempt to reserve more
  2445   // space than needed, it could confuse the collision detecting code. To
  2446   // solve the problem, save current _highest_vm_reserved_address and
  2447   // calculate the correct value before return.
  2448   address old_highest = _highest_vm_reserved_address;
  2450   // Bsd mmap allows caller to pass an address as hint; give it a try first,
  2451   // if kernel honors the hint then we can return immediately.
  2452   char * addr = anon_mmap(requested_addr, bytes, false);
  2453   if (addr == requested_addr) {
  2454      return requested_addr;
  2457   if (addr != NULL) {
  2458      // mmap() is successful but it fails to reserve at the requested address
  2459      anon_munmap(addr, bytes);
  2462   int i;
  2463   for (i = 0; i < max_tries; ++i) {
  2464     base[i] = reserve_memory(bytes);
  2466     if (base[i] != NULL) {
  2467       // Is this the block we wanted?
  2468       if (base[i] == requested_addr) {
  2469         size[i] = bytes;
  2470         break;
  2473       // Does this overlap the block we wanted? Give back the overlapped
  2474       // parts and try again.
  2476       size_t top_overlap = requested_addr + (bytes + gap) - base[i];
  2477       if (top_overlap >= 0 && top_overlap < bytes) {
  2478         unmap_memory(base[i], top_overlap);
  2479         base[i] += top_overlap;
  2480         size[i] = bytes - top_overlap;
  2481       } else {
  2482         size_t bottom_overlap = base[i] + bytes - requested_addr;
  2483         if (bottom_overlap >= 0 && bottom_overlap < bytes) {
  2484           unmap_memory(requested_addr, bottom_overlap);
  2485           size[i] = bytes - bottom_overlap;
  2486         } else {
  2487           size[i] = bytes;
  2493   // Give back the unused reserved pieces.
  2495   for (int j = 0; j < i; ++j) {
  2496     if (base[j] != NULL) {
  2497       unmap_memory(base[j], size[j]);
  2501   if (i < max_tries) {
  2502     _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
  2503     return requested_addr;
  2504   } else {
  2505     _highest_vm_reserved_address = old_highest;
  2506     return NULL;
  2510 size_t os::read(int fd, void *buf, unsigned int nBytes) {
  2511   RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
  2514 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
  2515 // Solaris uses poll(), bsd uses park().
  2516 // Poll() is likely a better choice, assuming that Thread.interrupt()
  2517 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
  2518 // SIGSEGV, see 4355769.
  2520 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
  2521   assert(thread == Thread::current(),  "thread consistency check");
  2523   ParkEvent * const slp = thread->_SleepEvent ;
  2524   slp->reset() ;
  2525   OrderAccess::fence() ;
  2527   if (interruptible) {
  2528     jlong prevtime = javaTimeNanos();
  2530     for (;;) {
  2531       if (os::is_interrupted(thread, true)) {
  2532         return OS_INTRPT;
  2535       jlong newtime = javaTimeNanos();
  2537       if (newtime - prevtime < 0) {
  2538         // time moving backwards, should only happen if no monotonic clock
  2539         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2540         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2541       } else {
  2542         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2545       if(millis <= 0) {
  2546         return OS_OK;
  2549       prevtime = newtime;
  2552         assert(thread->is_Java_thread(), "sanity check");
  2553         JavaThread *jt = (JavaThread *) thread;
  2554         ThreadBlockInVM tbivm(jt);
  2555         OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
  2557         jt->set_suspend_equivalent();
  2558         // cleared by handle_special_suspend_equivalent_condition() or
  2559         // java_suspend_self() via check_and_wait_while_suspended()
  2561         slp->park(millis);
  2563         // were we externally suspended while we were waiting?
  2564         jt->check_and_wait_while_suspended();
  2567   } else {
  2568     OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  2569     jlong prevtime = javaTimeNanos();
  2571     for (;;) {
  2572       // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
  2573       // the 1st iteration ...
  2574       jlong newtime = javaTimeNanos();
  2576       if (newtime - prevtime < 0) {
  2577         // time moving backwards, should only happen if no monotonic clock
  2578         // not a guarantee() because JVM should not abort on kernel/glibc bugs
  2579         assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
  2580       } else {
  2581         millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
  2584       if(millis <= 0) break ;
  2586       prevtime = newtime;
  2587       slp->park(millis);
  2589     return OS_OK ;
  2593 int os::naked_sleep() {
  2594   // %% make the sleep time an integer flag. for now use 1 millisec.
  2595   return os::sleep(Thread::current(), 1, false);
  2598 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
  2599 void os::infinite_sleep() {
  2600   while (true) {    // sleep forever ...
  2601     ::sleep(100);   // ... 100 seconds at a time
  2605 // Used to convert frequent JVM_Yield() to nops
  2606 bool os::dont_yield() {
  2607   return DontYieldALot;
  2610 void os::yield() {
  2611   sched_yield();
  2614 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
  2616 void os::yield_all(int attempts) {
  2617   // Yields to all threads, including threads with lower priorities
  2618   // Threads on Bsd are all with same priority. The Solaris style
  2619   // os::yield_all() with nanosleep(1ms) is not necessary.
  2620   sched_yield();
  2623 // Called from the tight loops to possibly influence time-sharing heuristics
  2624 void os::loop_breaker(int attempts) {
  2625   os::yield_all(attempts);
  2628 ////////////////////////////////////////////////////////////////////////////////
  2629 // thread priority support
  2631 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
  2632 // only supports dynamic priority, static priority must be zero. For real-time
  2633 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
  2634 // However, for large multi-threaded applications, SCHED_RR is not only slower
  2635 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
  2636 // of 5 runs - Sep 2005).
  2637 //
  2638 // The following code actually changes the niceness of kernel-thread/LWP. It
  2639 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
  2640 // not the entire user process, and user level threads are 1:1 mapped to kernel
  2641 // threads. It has always been the case, but could change in the future. For
  2642 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
  2643 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
  2645 #if !defined(__APPLE__)
  2646 int os::java_to_os_priority[CriticalPriority + 1] = {
  2647   19,              // 0 Entry should never be used
  2649    0,              // 1 MinPriority
  2650    3,              // 2
  2651    6,              // 3
  2653   10,              // 4
  2654   15,              // 5 NormPriority
  2655   18,              // 6
  2657   21,              // 7
  2658   25,              // 8
  2659   28,              // 9 NearMaxPriority
  2661   31,              // 10 MaxPriority
  2663   31               // 11 CriticalPriority
  2664 };
  2665 #else
  2666 /* Using Mach high-level priority assignments */
  2667 int os::java_to_os_priority[CriticalPriority + 1] = {
  2668    0,              // 0 Entry should never be used (MINPRI_USER)
  2670   27,              // 1 MinPriority
  2671   28,              // 2
  2672   29,              // 3
  2674   30,              // 4
  2675   31,              // 5 NormPriority (BASEPRI_DEFAULT)
  2676   32,              // 6
  2678   33,              // 7
  2679   34,              // 8
  2680   35,              // 9 NearMaxPriority
  2682   36,              // 10 MaxPriority
  2684   36               // 11 CriticalPriority
  2685 };
  2686 #endif
  2688 static int prio_init() {
  2689   if (ThreadPriorityPolicy == 1) {
  2690     // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
  2691     // if effective uid is not root. Perhaps, a more elegant way of doing
  2692     // this is to test CAP_SYS_NICE capability, but that will require libcap.so
  2693     if (geteuid() != 0) {
  2694       if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
  2695         warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
  2697       ThreadPriorityPolicy = 0;
  2700   if (UseCriticalJavaThreadPriority) {
  2701     os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
  2703   return 0;
  2706 OSReturn os::set_native_priority(Thread* thread, int newpri) {
  2707   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
  2709 #ifdef __OpenBSD__
  2710   // OpenBSD pthread_setprio starves low priority threads
  2711   return OS_OK;
  2712 #elif defined(__FreeBSD__)
  2713   int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
  2714 #elif defined(__APPLE__) || defined(__NetBSD__)
  2715   struct sched_param sp;
  2716   int policy;
  2717   pthread_t self = pthread_self();
  2719   if (pthread_getschedparam(self, &policy, &sp) != 0)
  2720     return OS_ERR;
  2722   sp.sched_priority = newpri;
  2723   if (pthread_setschedparam(self, policy, &sp) != 0)
  2724     return OS_ERR;
  2726   return OS_OK;
  2727 #else
  2728   int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
  2729   return (ret == 0) ? OS_OK : OS_ERR;
  2730 #endif
  2733 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
  2734   if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
  2735     *priority_ptr = java_to_os_priority[NormPriority];
  2736     return OS_OK;
  2739   errno = 0;
  2740 #if defined(__OpenBSD__) || defined(__FreeBSD__)
  2741   *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
  2742 #elif defined(__APPLE__) || defined(__NetBSD__)
  2743   int policy;
  2744   struct sched_param sp;
  2746   pthread_getschedparam(pthread_self(), &policy, &sp);
  2747   *priority_ptr = sp.sched_priority;
  2748 #else
  2749   *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
  2750 #endif
  2751   return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
  2754 // Hint to the underlying OS that a task switch would not be good.
  2755 // Void return because it's a hint and can fail.
  2756 void os::hint_no_preempt() {}
  2758 ////////////////////////////////////////////////////////////////////////////////
  2759 // suspend/resume support
  2761 //  the low-level signal-based suspend/resume support is a remnant from the
  2762 //  old VM-suspension that used to be for java-suspension, safepoints etc,
  2763 //  within hotspot. Now there is a single use-case for this:
  2764 //    - calling get_thread_pc() on the VMThread by the flat-profiler task
  2765 //      that runs in the watcher thread.
  2766 //  The remaining code is greatly simplified from the more general suspension
  2767 //  code that used to be used.
  2768 //
  2769 //  The protocol is quite simple:
  2770 //  - suspend:
  2771 //      - sends a signal to the target thread
  2772 //      - polls the suspend state of the osthread using a yield loop
  2773 //      - target thread signal handler (SR_handler) sets suspend state
  2774 //        and blocks in sigsuspend until continued
  2775 //  - resume:
  2776 //      - sets target osthread state to continue
  2777 //      - sends signal to end the sigsuspend loop in the SR_handler
  2778 //
  2779 //  Note that the SR_lock plays no role in this suspend/resume protocol.
  2780 //
  2782 static void resume_clear_context(OSThread *osthread) {
  2783   osthread->set_ucontext(NULL);
  2784   osthread->set_siginfo(NULL);
  2787 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
  2788   osthread->set_ucontext(context);
  2789   osthread->set_siginfo(siginfo);
  2792 //
  2793 // Handler function invoked when a thread's execution is suspended or
  2794 // resumed. We have to be careful that only async-safe functions are
  2795 // called here (Note: most pthread functions are not async safe and
  2796 // should be avoided.)
  2797 //
  2798 // Note: sigwait() is a more natural fit than sigsuspend() from an
  2799 // interface point of view, but sigwait() prevents the signal hander
  2800 // from being run. libpthread would get very confused by not having
  2801 // its signal handlers run and prevents sigwait()'s use with the
  2802 // mutex granting granting signal.
  2803 //
  2804 // Currently only ever called on the VMThread or JavaThread
  2805 //
  2806 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
  2807   // Save and restore errno to avoid confusing native code with EINTR
  2808   // after sigsuspend.
  2809   int old_errno = errno;
  2811   Thread* thread = Thread::current();
  2812   OSThread* osthread = thread->osthread();
  2813   assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
  2815   os::SuspendResume::State current = osthread->sr.state();
  2816   if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
  2817     suspend_save_context(osthread, siginfo, context);
  2819     // attempt to switch the state, we assume we had a SUSPEND_REQUEST
  2820     os::SuspendResume::State state = osthread->sr.suspended();
  2821     if (state == os::SuspendResume::SR_SUSPENDED) {
  2822       sigset_t suspend_set;  // signals for sigsuspend()
  2824       // get current set of blocked signals and unblock resume signal
  2825       pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
  2826       sigdelset(&suspend_set, SR_signum);
  2828       sr_semaphore.signal();
  2829       // wait here until we are resumed
  2830       while (1) {
  2831         sigsuspend(&suspend_set);
  2833         os::SuspendResume::State result = osthread->sr.running();
  2834         if (result == os::SuspendResume::SR_RUNNING) {
  2835           sr_semaphore.signal();
  2836           break;
  2837         } else if (result != os::SuspendResume::SR_SUSPENDED) {
  2838           ShouldNotReachHere();
  2842     } else if (state == os::SuspendResume::SR_RUNNING) {
  2843       // request was cancelled, continue
  2844     } else {
  2845       ShouldNotReachHere();
  2848     resume_clear_context(osthread);
  2849   } else if (current == os::SuspendResume::SR_RUNNING) {
  2850     // request was cancelled, continue
  2851   } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
  2852     // ignore
  2853   } else {
  2854     // ignore
  2857   errno = old_errno;
  2861 static int SR_initialize() {
  2862   struct sigaction act;
  2863   char *s;
  2864   /* Get signal number to use for suspend/resume */
  2865   if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
  2866     int sig = ::strtol(s, 0, 10);
  2867     if (sig > 0 || sig < NSIG) {
  2868         SR_signum = sig;
  2872   assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
  2873         "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
  2875   sigemptyset(&SR_sigset);
  2876   sigaddset(&SR_sigset, SR_signum);
  2878   /* Set up signal handler for suspend/resume */
  2879   act.sa_flags = SA_RESTART|SA_SIGINFO;
  2880   act.sa_handler = (void (*)(int)) SR_handler;
  2882   // SR_signum is blocked by default.
  2883   // 4528190 - We also need to block pthread restart signal (32 on all
  2884   // supported Bsd platforms). Note that BsdThreads need to block
  2885   // this signal for all threads to work properly. So we don't have
  2886   // to use hard-coded signal number when setting up the mask.
  2887   pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
  2889   if (sigaction(SR_signum, &act, 0) == -1) {
  2890     return -1;
  2893   // Save signal flag
  2894   os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
  2895   return 0;
  2898 static int sr_notify(OSThread* osthread) {
  2899   int status = pthread_kill(osthread->pthread_id(), SR_signum);
  2900   assert_status(status == 0, status, "pthread_kill");
  2901   return status;
  2904 // "Randomly" selected value for how long we want to spin
  2905 // before bailing out on suspending a thread, also how often
  2906 // we send a signal to a thread we want to resume
  2907 static const int RANDOMLY_LARGE_INTEGER = 1000000;
  2908 static const int RANDOMLY_LARGE_INTEGER2 = 100;
  2910 // returns true on success and false on error - really an error is fatal
  2911 // but this seems the normal response to library errors
  2912 static bool do_suspend(OSThread* osthread) {
  2913   assert(osthread->sr.is_running(), "thread should be running");
  2914   assert(!sr_semaphore.trywait(), "semaphore has invalid state");
  2916   // mark as suspended and send signal
  2917   if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
  2918     // failed to switch, state wasn't running?
  2919     ShouldNotReachHere();
  2920     return false;
  2923   if (sr_notify(osthread) != 0) {
  2924     ShouldNotReachHere();
  2927   // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
  2928   while (true) {
  2929     if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
  2930       break;
  2931     } else {
  2932       // timeout
  2933       os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
  2934       if (cancelled == os::SuspendResume::SR_RUNNING) {
  2935         return false;
  2936       } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
  2937         // make sure that we consume the signal on the semaphore as well
  2938         sr_semaphore.wait();
  2939         break;
  2940       } else {
  2941         ShouldNotReachHere();
  2942         return false;
  2947   guarantee(osthread->sr.is_suspended(), "Must be suspended");
  2948   return true;
  2951 static void do_resume(OSThread* osthread) {
  2952   assert(osthread->sr.is_suspended(), "thread should be suspended");
  2953   assert(!sr_semaphore.trywait(), "invalid semaphore state");
  2955   if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
  2956     // failed to switch to WAKEUP_REQUEST
  2957     ShouldNotReachHere();
  2958     return;
  2961   while (true) {
  2962     if (sr_notify(osthread) == 0) {
  2963       if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
  2964         if (osthread->sr.is_running()) {
  2965           return;
  2968     } else {
  2969       ShouldNotReachHere();
  2973   guarantee(osthread->sr.is_running(), "Must be running!");
  2976 ////////////////////////////////////////////////////////////////////////////////
  2977 // interrupt support
  2979 void os::interrupt(Thread* thread) {
  2980   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  2981     "possibility of dangling Thread pointer");
  2983   OSThread* osthread = thread->osthread();
  2985   if (!osthread->interrupted()) {
  2986     osthread->set_interrupted(true);
  2987     // More than one thread can get here with the same value of osthread,
  2988     // resulting in multiple notifications.  We do, however, want the store
  2989     // to interrupted() to be visible to other threads before we execute unpark().
  2990     OrderAccess::fence();
  2991     ParkEvent * const slp = thread->_SleepEvent ;
  2992     if (slp != NULL) slp->unpark() ;
  2995   // For JSR166. Unpark even if interrupt status already was set
  2996   if (thread->is_Java_thread())
  2997     ((JavaThread*)thread)->parker()->unpark();
  2999   ParkEvent * ev = thread->_ParkEvent ;
  3000   if (ev != NULL) ev->unpark() ;
  3004 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
  3005   assert(Thread::current() == thread || Threads_lock->owned_by_self(),
  3006     "possibility of dangling Thread pointer");
  3008   OSThread* osthread = thread->osthread();
  3010   bool interrupted = osthread->interrupted();
  3012   if (interrupted && clear_interrupted) {
  3013     osthread->set_interrupted(false);
  3014     // consider thread->_SleepEvent->reset() ... optional optimization
  3017   return interrupted;
  3020 ///////////////////////////////////////////////////////////////////////////////////
  3021 // signal handling (except suspend/resume)
  3023 // This routine may be used by user applications as a "hook" to catch signals.
  3024 // The user-defined signal handler must pass unrecognized signals to this
  3025 // routine, and if it returns true (non-zero), then the signal handler must
  3026 // return immediately.  If the flag "abort_if_unrecognized" is true, then this
  3027 // routine will never retun false (zero), but instead will execute a VM panic
  3028 // routine kill the process.
  3029 //
  3030 // If this routine returns false, it is OK to call it again.  This allows
  3031 // the user-defined signal handler to perform checks either before or after
  3032 // the VM performs its own checks.  Naturally, the user code would be making
  3033 // a serious error if it tried to handle an exception (such as a null check
  3034 // or breakpoint) that the VM was generating for its own correct operation.
  3035 //
  3036 // This routine may recognize any of the following kinds of signals:
  3037 //    SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
  3038 // It should be consulted by handlers for any of those signals.
  3039 //
  3040 // The caller of this routine must pass in the three arguments supplied
  3041 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
  3042 // field of the structure passed to sigaction().  This routine assumes that
  3043 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
  3044 //
  3045 // Note that the VM will print warnings if it detects conflicting signal
  3046 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
  3047 //
  3048 extern "C" JNIEXPORT int
  3049 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
  3050                         void* ucontext, int abort_if_unrecognized);
  3052 void signalHandler(int sig, siginfo_t* info, void* uc) {
  3053   assert(info != NULL && uc != NULL, "it must be old kernel");
  3054   int orig_errno = errno;  // Preserve errno value over signal handler.
  3055   JVM_handle_bsd_signal(sig, info, uc, true);
  3056   errno = orig_errno;
  3060 // This boolean allows users to forward their own non-matching signals
  3061 // to JVM_handle_bsd_signal, harmlessly.
  3062 bool os::Bsd::signal_handlers_are_installed = false;
  3064 // For signal-chaining
  3065 struct sigaction os::Bsd::sigact[MAXSIGNUM];
  3066 unsigned int os::Bsd::sigs = 0;
  3067 bool os::Bsd::libjsig_is_loaded = false;
  3068 typedef struct sigaction *(*get_signal_t)(int);
  3069 get_signal_t os::Bsd::get_signal_action = NULL;
  3071 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
  3072   struct sigaction *actp = NULL;
  3074   if (libjsig_is_loaded) {
  3075     // Retrieve the old signal handler from libjsig
  3076     actp = (*get_signal_action)(sig);
  3078   if (actp == NULL) {
  3079     // Retrieve the preinstalled signal handler from jvm
  3080     actp = get_preinstalled_handler(sig);
  3083   return actp;
  3086 static bool call_chained_handler(struct sigaction *actp, int sig,
  3087                                  siginfo_t *siginfo, void *context) {
  3088   // Call the old signal handler
  3089   if (actp->sa_handler == SIG_DFL) {
  3090     // It's more reasonable to let jvm treat it as an unexpected exception
  3091     // instead of taking the default action.
  3092     return false;
  3093   } else if (actp->sa_handler != SIG_IGN) {
  3094     if ((actp->sa_flags & SA_NODEFER) == 0) {
  3095       // automaticlly block the signal
  3096       sigaddset(&(actp->sa_mask), sig);
  3099     sa_handler_t hand;
  3100     sa_sigaction_t sa;
  3101     bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
  3102     // retrieve the chained handler
  3103     if (siginfo_flag_set) {
  3104       sa = actp->sa_sigaction;
  3105     } else {
  3106       hand = actp->sa_handler;
  3109     if ((actp->sa_flags & SA_RESETHAND) != 0) {
  3110       actp->sa_handler = SIG_DFL;
  3113     // try to honor the signal mask
  3114     sigset_t oset;
  3115     pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
  3117     // call into the chained handler
  3118     if (siginfo_flag_set) {
  3119       (*sa)(sig, siginfo, context);
  3120     } else {
  3121       (*hand)(sig);
  3124     // restore the signal mask
  3125     pthread_sigmask(SIG_SETMASK, &oset, 0);
  3127   // Tell jvm's signal handler the signal is taken care of.
  3128   return true;
  3131 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
  3132   bool chained = false;
  3133   // signal-chaining
  3134   if (UseSignalChaining) {
  3135     struct sigaction *actp = get_chained_signal_action(sig);
  3136     if (actp != NULL) {
  3137       chained = call_chained_handler(actp, sig, siginfo, context);
  3140   return chained;
  3143 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
  3144   if ((( (unsigned int)1 << sig ) & sigs) != 0) {
  3145     return &sigact[sig];
  3147   return NULL;
  3150 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
  3151   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3152   sigact[sig] = oldAct;
  3153   sigs |= (unsigned int)1 << sig;
  3156 // for diagnostic
  3157 int os::Bsd::sigflags[MAXSIGNUM];
  3159 int os::Bsd::get_our_sigflags(int sig) {
  3160   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3161   return sigflags[sig];
  3164 void os::Bsd::set_our_sigflags(int sig, int flags) {
  3165   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3166   sigflags[sig] = flags;
  3169 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
  3170   // Check for overwrite.
  3171   struct sigaction oldAct;
  3172   sigaction(sig, (struct sigaction*)NULL, &oldAct);
  3174   void* oldhand = oldAct.sa_sigaction
  3175                 ? CAST_FROM_FN_PTR(void*,  oldAct.sa_sigaction)
  3176                 : CAST_FROM_FN_PTR(void*,  oldAct.sa_handler);
  3177   if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
  3178       oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
  3179       oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
  3180     if (AllowUserSignalHandlers || !set_installed) {
  3181       // Do not overwrite; user takes responsibility to forward to us.
  3182       return;
  3183     } else if (UseSignalChaining) {
  3184       // save the old handler in jvm
  3185       save_preinstalled_handler(sig, oldAct);
  3186       // libjsig also interposes the sigaction() call below and saves the
  3187       // old sigaction on it own.
  3188     } else {
  3189       fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
  3190                     "%#lx for signal %d.", (long)oldhand, sig));
  3194   struct sigaction sigAct;
  3195   sigfillset(&(sigAct.sa_mask));
  3196   sigAct.sa_handler = SIG_DFL;
  3197   if (!set_installed) {
  3198     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3199   } else {
  3200     sigAct.sa_sigaction = signalHandler;
  3201     sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
  3203 #if __APPLE__
  3204   // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
  3205   // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
  3206   // if the signal handler declares it will handle it on alternate stack.
  3207   // Notice we only declare we will handle it on alt stack, but we are not
  3208   // actually going to use real alt stack - this is just a workaround.
  3209   // Please see ux_exception.c, method catch_mach_exception_raise for details
  3210   // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
  3211   if (sig == SIGSEGV) {
  3212     sigAct.sa_flags |= SA_ONSTACK;
  3214 #endif
  3216   // Save flags, which are set by ours
  3217   assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
  3218   sigflags[sig] = sigAct.sa_flags;
  3220   int ret = sigaction(sig, &sigAct, &oldAct);
  3221   assert(ret == 0, "check");
  3223   void* oldhand2  = oldAct.sa_sigaction
  3224                   ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
  3225                   : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
  3226   assert(oldhand2 == oldhand, "no concurrent signal handler installation");
  3229 // install signal handlers for signals that HotSpot needs to
  3230 // handle in order to support Java-level exception handling.
  3232 void os::Bsd::install_signal_handlers() {
  3233   if (!signal_handlers_are_installed) {
  3234     signal_handlers_are_installed = true;
  3236     // signal-chaining
  3237     typedef void (*signal_setting_t)();
  3238     signal_setting_t begin_signal_setting = NULL;
  3239     signal_setting_t end_signal_setting = NULL;
  3240     begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3241                              dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
  3242     if (begin_signal_setting != NULL) {
  3243       end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
  3244                              dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
  3245       get_signal_action = CAST_TO_FN_PTR(get_signal_t,
  3246                             dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
  3247       libjsig_is_loaded = true;
  3248       assert(UseSignalChaining, "should enable signal-chaining");
  3250     if (libjsig_is_loaded) {
  3251       // Tell libjsig jvm is setting signal handlers
  3252       (*begin_signal_setting)();
  3255     set_signal_handler(SIGSEGV, true);
  3256     set_signal_handler(SIGPIPE, true);
  3257     set_signal_handler(SIGBUS, true);
  3258     set_signal_handler(SIGILL, true);
  3259     set_signal_handler(SIGFPE, true);
  3260     set_signal_handler(SIGXFSZ, true);
  3262 #if defined(__APPLE__)
  3263     // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
  3264     // signals caught and handled by the JVM. To work around this, we reset the mach task
  3265     // signal handler that's placed on our process by CrashReporter. This disables
  3266     // CrashReporter-based reporting.
  3267     //
  3268     // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
  3269     // on caught fatal signals.
  3270     //
  3271     // Additionally, gdb installs both standard BSD signal handlers, and mach exception
  3272     // handlers. By replacing the existing task exception handler, we disable gdb's mach
  3273     // exception handling, while leaving the standard BSD signal handlers functional.
  3274     kern_return_t kr;
  3275     kr = task_set_exception_ports(mach_task_self(),
  3276         EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
  3277         MACH_PORT_NULL,
  3278         EXCEPTION_STATE_IDENTITY,
  3279         MACHINE_THREAD_STATE);
  3281     assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
  3282 #endif
  3284     if (libjsig_is_loaded) {
  3285       // Tell libjsig jvm finishes setting signal handlers
  3286       (*end_signal_setting)();
  3289     // We don't activate signal checker if libjsig is in place, we trust ourselves
  3290     // and if UserSignalHandler is installed all bets are off
  3291     if (CheckJNICalls) {
  3292       if (libjsig_is_loaded) {
  3293         if (PrintJNIResolving) {
  3294           tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
  3296         check_signals = false;
  3298       if (AllowUserSignalHandlers) {
  3299         if (PrintJNIResolving) {
  3300           tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
  3302         check_signals = false;
  3309 /////
  3310 // glibc on Bsd platform uses non-documented flag
  3311 // to indicate, that some special sort of signal
  3312 // trampoline is used.
  3313 // We will never set this flag, and we should
  3314 // ignore this flag in our diagnostic
  3315 #ifdef SIGNIFICANT_SIGNAL_MASK
  3316 #undef SIGNIFICANT_SIGNAL_MASK
  3317 #endif
  3318 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
  3320 static const char* get_signal_handler_name(address handler,
  3321                                            char* buf, int buflen) {
  3322   int offset;
  3323   bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
  3324   if (found) {
  3325     // skip directory names
  3326     const char *p1, *p2;
  3327     p1 = buf;
  3328     size_t len = strlen(os::file_separator());
  3329     while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
  3330     jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
  3331   } else {
  3332     jio_snprintf(buf, buflen, PTR_FORMAT, handler);
  3334   return buf;
  3337 static void print_signal_handler(outputStream* st, int sig,
  3338                                  char* buf, size_t buflen) {
  3339   struct sigaction sa;
  3341   sigaction(sig, NULL, &sa);
  3343   // See comment for SIGNIFICANT_SIGNAL_MASK define
  3344   sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3346   st->print("%s: ", os::exception_name(sig, buf, buflen));
  3348   address handler = (sa.sa_flags & SA_SIGINFO)
  3349     ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
  3350     : CAST_FROM_FN_PTR(address, sa.sa_handler);
  3352   if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
  3353     st->print("SIG_DFL");
  3354   } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
  3355     st->print("SIG_IGN");
  3356   } else {
  3357     st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
  3360   st->print(", sa_mask[0]=");
  3361   os::Posix::print_signal_set_short(st, &sa.sa_mask);
  3363   address rh = VMError::get_resetted_sighandler(sig);
  3364   // May be, handler was resetted by VMError?
  3365   if(rh != NULL) {
  3366     handler = rh;
  3367     sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
  3370   st->print(", sa_flags=");
  3371   os::Posix::print_sa_flags(st, sa.sa_flags);
  3373   // Check: is it our handler?
  3374   if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
  3375      handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
  3376     // It is our signal handler
  3377     // check for flags, reset system-used one!
  3378     if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3379       st->print(
  3380                 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
  3381                 os::Bsd::get_our_sigflags(sig));
  3384   st->cr();
  3388 #define DO_SIGNAL_CHECK(sig) \
  3389   if (!sigismember(&check_signal_done, sig)) \
  3390     os::Bsd::check_signal_handler(sig)
  3392 // This method is a periodic task to check for misbehaving JNI applications
  3393 // under CheckJNI, we can add any periodic checks here
  3395 void os::run_periodic_checks() {
  3397   if (check_signals == false) return;
  3399   // SEGV and BUS if overridden could potentially prevent
  3400   // generation of hs*.log in the event of a crash, debugging
  3401   // such a case can be very challenging, so we absolutely
  3402   // check the following for a good measure:
  3403   DO_SIGNAL_CHECK(SIGSEGV);
  3404   DO_SIGNAL_CHECK(SIGILL);
  3405   DO_SIGNAL_CHECK(SIGFPE);
  3406   DO_SIGNAL_CHECK(SIGBUS);
  3407   DO_SIGNAL_CHECK(SIGPIPE);
  3408   DO_SIGNAL_CHECK(SIGXFSZ);
  3411   // ReduceSignalUsage allows the user to override these handlers
  3412   // see comments at the very top and jvm_solaris.h
  3413   if (!ReduceSignalUsage) {
  3414     DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
  3415     DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
  3416     DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
  3417     DO_SIGNAL_CHECK(BREAK_SIGNAL);
  3420   DO_SIGNAL_CHECK(SR_signum);
  3421   DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
  3424 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
  3426 static os_sigaction_t os_sigaction = NULL;
  3428 void os::Bsd::check_signal_handler(int sig) {
  3429   char buf[O_BUFLEN];
  3430   address jvmHandler = NULL;
  3433   struct sigaction act;
  3434   if (os_sigaction == NULL) {
  3435     // only trust the default sigaction, in case it has been interposed
  3436     os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
  3437     if (os_sigaction == NULL) return;
  3440   os_sigaction(sig, (struct sigaction*)NULL, &act);
  3443   act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
  3445   address thisHandler = (act.sa_flags & SA_SIGINFO)
  3446     ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
  3447     : CAST_FROM_FN_PTR(address, act.sa_handler) ;
  3450   switch(sig) {
  3451   case SIGSEGV:
  3452   case SIGBUS:
  3453   case SIGFPE:
  3454   case SIGPIPE:
  3455   case SIGILL:
  3456   case SIGXFSZ:
  3457     jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
  3458     break;
  3460   case SHUTDOWN1_SIGNAL:
  3461   case SHUTDOWN2_SIGNAL:
  3462   case SHUTDOWN3_SIGNAL:
  3463   case BREAK_SIGNAL:
  3464     jvmHandler = (address)user_handler();
  3465     break;
  3467   case INTERRUPT_SIGNAL:
  3468     jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
  3469     break;
  3471   default:
  3472     if (sig == SR_signum) {
  3473       jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
  3474     } else {
  3475       return;
  3477     break;
  3480   if (thisHandler != jvmHandler) {
  3481     tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
  3482     tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
  3483     tty->print_cr("  found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
  3484     // No need to check this sig any longer
  3485     sigaddset(&check_signal_done, sig);
  3486   } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
  3487     tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
  3488     tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
  3489     tty->print_cr("  found:" PTR32_FORMAT, act.sa_flags);
  3490     // No need to check this sig any longer
  3491     sigaddset(&check_signal_done, sig);
  3494   // Dump all the signal
  3495   if (sigismember(&check_signal_done, sig)) {
  3496     print_signal_handlers(tty, buf, O_BUFLEN);
  3500 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
  3502 extern bool signal_name(int signo, char* buf, size_t len);
  3504 const char* os::exception_name(int exception_code, char* buf, size_t size) {
  3505   if (0 < exception_code && exception_code <= SIGRTMAX) {
  3506     // signal
  3507     if (!signal_name(exception_code, buf, size)) {
  3508       jio_snprintf(buf, size, "SIG%d", exception_code);
  3510     return buf;
  3511   } else {
  3512     return NULL;
  3516 // this is called _before_ the most of global arguments have been parsed
  3517 void os::init(void) {
  3518   char dummy;   /* used to get a guess on initial stack address */
  3519 //  first_hrtime = gethrtime();
  3521   // With BsdThreads the JavaMain thread pid (primordial thread)
  3522   // is different than the pid of the java launcher thread.
  3523   // So, on Bsd, the launcher thread pid is passed to the VM
  3524   // via the sun.java.launcher.pid property.
  3525   // Use this property instead of getpid() if it was correctly passed.
  3526   // See bug 6351349.
  3527   pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
  3529   _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
  3531   clock_tics_per_sec = CLK_TCK;
  3533   init_random(1234567);
  3535   ThreadCritical::initialize();
  3537   Bsd::set_page_size(getpagesize());
  3538   if (Bsd::page_size() == -1) {
  3539     fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
  3540                   strerror(errno)));
  3542   init_page_sizes((size_t) Bsd::page_size());
  3544   Bsd::initialize_system_info();
  3546   // main_thread points to the aboriginal thread
  3547   Bsd::_main_thread = pthread_self();
  3549   Bsd::clock_init();
  3550   initial_time_count = javaTimeNanos();
  3552 #ifdef __APPLE__
  3553   // XXXDARWIN
  3554   // Work around the unaligned VM callbacks in hotspot's
  3555   // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
  3556   // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
  3557   // alignment when doing symbol lookup. To work around this, we force early
  3558   // binding of all symbols now, thus binding when alignment is known-good.
  3559   _dyld_bind_fully_image_containing_address((const void *) &os::init);
  3560 #endif
  3563 // To install functions for atexit system call
  3564 extern "C" {
  3565   static void perfMemory_exit_helper() {
  3566     perfMemory_exit();
  3570 // this is called _after_ the global arguments have been parsed
  3571 jint os::init_2(void)
  3573   // Allocate a single page and mark it as readable for safepoint polling
  3574   address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3575   guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
  3577   os::set_polling_page( polling_page );
  3579 #ifndef PRODUCT
  3580   if(Verbose && PrintMiscellaneous)
  3581     tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
  3582 #endif
  3584   if (!UseMembar) {
  3585     address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  3586     guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
  3587     os::set_memory_serialize_page( mem_serialize_page );
  3589 #ifndef PRODUCT
  3590     if(Verbose && PrintMiscellaneous)
  3591       tty->print("[Memory Serialize  Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
  3592 #endif
  3595   // initialize suspend/resume support - must do this before signal_sets_init()
  3596   if (SR_initialize() != 0) {
  3597     perror("SR_initialize failed");
  3598     return JNI_ERR;
  3601   Bsd::signal_sets_init();
  3602   Bsd::install_signal_handlers();
  3604   // Check minimum allowable stack size for thread creation and to initialize
  3605   // the java system classes, including StackOverflowError - depends on page
  3606   // size.  Add a page for compiler2 recursion in main thread.
  3607   // Add in 2*BytesPerWord times page size to account for VM stack during
  3608   // class initialization depending on 32 or 64 bit VM.
  3609   os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
  3610             (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
  3611                     2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
  3613   size_t threadStackSizeInBytes = ThreadStackSize * K;
  3614   if (threadStackSizeInBytes != 0 &&
  3615       threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
  3616         tty->print_cr("\nThe stack size specified is too small, "
  3617                       "Specify at least %dk",
  3618                       os::Bsd::min_stack_allowed/ K);
  3619         return JNI_ERR;
  3622   // Make the stack size a multiple of the page size so that
  3623   // the yellow/red zones can be guarded.
  3624   JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
  3625         vm_page_size()));
  3627   if (MaxFDLimit) {
  3628     // set the number of file descriptors to max. print out error
  3629     // if getrlimit/setrlimit fails but continue regardless.
  3630     struct rlimit nbr_files;
  3631     int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
  3632     if (status != 0) {
  3633       if (PrintMiscellaneous && (Verbose || WizardMode))
  3634         perror("os::init_2 getrlimit failed");
  3635     } else {
  3636       nbr_files.rlim_cur = nbr_files.rlim_max;
  3638 #ifdef __APPLE__
  3639       // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
  3640       // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
  3641       // be used instead
  3642       nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
  3643 #endif
  3645       status = setrlimit(RLIMIT_NOFILE, &nbr_files);
  3646       if (status != 0) {
  3647         if (PrintMiscellaneous && (Verbose || WizardMode))
  3648           perror("os::init_2 setrlimit failed");
  3653   // at-exit methods are called in the reverse order of their registration.
  3654   // atexit functions are called on return from main or as a result of a
  3655   // call to exit(3C). There can be only 32 of these functions registered
  3656   // and atexit() does not set errno.
  3658   if (PerfAllowAtExitRegistration) {
  3659     // only register atexit functions if PerfAllowAtExitRegistration is set.
  3660     // atexit functions can be delayed until process exit time, which
  3661     // can be problematic for embedded VM situations. Embedded VMs should
  3662     // call DestroyJavaVM() to assure that VM resources are released.
  3664     // note: perfMemory_exit_helper atexit function may be removed in
  3665     // the future if the appropriate cleanup code can be added to the
  3666     // VM_Exit VMOperation's doit method.
  3667     if (atexit(perfMemory_exit_helper) != 0) {
  3668       warning("os::init2 atexit(perfMemory_exit_helper) failed");
  3672   // initialize thread priority policy
  3673   prio_init();
  3675 #ifdef __APPLE__
  3676   // dynamically link to objective c gc registration
  3677   void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
  3678   if (handleLibObjc != NULL) {
  3679     objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
  3681 #endif
  3683   return JNI_OK;
  3686 // this is called at the end of vm_initialization
  3687 void os::init_3(void) { }
  3689 // Mark the polling page as unreadable
  3690 void os::make_polling_page_unreadable(void) {
  3691   if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
  3692     fatal("Could not disable polling page");
  3693 };
  3695 // Mark the polling page as readable
  3696 void os::make_polling_page_readable(void) {
  3697   if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
  3698     fatal("Could not enable polling page");
  3700 };
  3702 int os::active_processor_count() {
  3703   return _processor_count;
  3706 void os::set_native_thread_name(const char *name) {
  3707 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
  3708   // This is only supported in Snow Leopard and beyond
  3709   if (name != NULL) {
  3710     // Add a "Java: " prefix to the name
  3711     char buf[MAXTHREADNAMESIZE];
  3712     snprintf(buf, sizeof(buf), "Java: %s", name);
  3713     pthread_setname_np(buf);
  3715 #endif
  3718 bool os::distribute_processes(uint length, uint* distribution) {
  3719   // Not yet implemented.
  3720   return false;
  3723 bool os::bind_to_processor(uint processor_id) {
  3724   // Not yet implemented.
  3725   return false;
  3728 void os::SuspendedThreadTask::internal_do_task() {
  3729   if (do_suspend(_thread->osthread())) {
  3730     SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
  3731     do_task(context);
  3732     do_resume(_thread->osthread());
  3736 ///
  3737 class PcFetcher : public os::SuspendedThreadTask {
  3738 public:
  3739   PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
  3740   ExtendedPC result();
  3741 protected:
  3742   void do_task(const os::SuspendedThreadTaskContext& context);
  3743 private:
  3744   ExtendedPC _epc;
  3745 };
  3747 ExtendedPC PcFetcher::result() {
  3748   guarantee(is_done(), "task is not done yet.");
  3749   return _epc;
  3752 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
  3753   Thread* thread = context.thread();
  3754   OSThread* osthread = thread->osthread();
  3755   if (osthread->ucontext() != NULL) {
  3756     _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
  3757   } else {
  3758     // NULL context is unexpected, double-check this is the VMThread
  3759     guarantee(thread->is_VM_thread(), "can only be called for VMThread");
  3763 // Suspends the target using the signal mechanism and then grabs the PC before
  3764 // resuming the target. Used by the flat-profiler only
  3765 ExtendedPC os::get_thread_pc(Thread* thread) {
  3766   // Make sure that it is called by the watcher for the VMThread
  3767   assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
  3768   assert(thread->is_VM_thread(), "Can only be called for VMThread");
  3770   PcFetcher fetcher(thread);
  3771   fetcher.run();
  3772   return fetcher.result();
  3775 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
  3777   return pthread_cond_timedwait(_cond, _mutex, _abstime);
  3780 ////////////////////////////////////////////////////////////////////////////////
  3781 // debug support
  3783 bool os::find(address addr, outputStream* st) {
  3784   Dl_info dlinfo;
  3785   memset(&dlinfo, 0, sizeof(dlinfo));
  3786   if (dladdr(addr, &dlinfo) != 0) {
  3787     st->print(PTR_FORMAT ": ", addr);
  3788     if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
  3789       st->print("%s+%#x", dlinfo.dli_sname,
  3790                  addr - (intptr_t)dlinfo.dli_saddr);
  3791     } else if (dlinfo.dli_fbase != NULL) {
  3792       st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
  3793     } else {
  3794       st->print("<absolute address>");
  3796     if (dlinfo.dli_fname != NULL) {
  3797       st->print(" in %s", dlinfo.dli_fname);
  3799     if (dlinfo.dli_fbase != NULL) {
  3800       st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
  3802     st->cr();
  3804     if (Verbose) {
  3805       // decode some bytes around the PC
  3806       address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
  3807       address end   = clamp_address_in_page(addr+40, addr, os::vm_page_size());
  3808       address       lowest = (address) dlinfo.dli_sname;
  3809       if (!lowest)  lowest = (address) dlinfo.dli_fbase;
  3810       if (begin < lowest)  begin = lowest;
  3811       Dl_info dlinfo2;
  3812       if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
  3813           && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
  3814         end = (address) dlinfo2.dli_saddr;
  3815       Disassembler::decode(begin, end, st);
  3817     return true;
  3819   return false;
  3822 ////////////////////////////////////////////////////////////////////////////////
  3823 // misc
  3825 // This does not do anything on Bsd. This is basically a hook for being
  3826 // able to use structured exception handling (thread-local exception filters)
  3827 // on, e.g., Win32.
  3828 void
  3829 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
  3830                          JavaCallArguments* args, Thread* thread) {
  3831   f(value, method, args, thread);
  3834 void os::print_statistics() {
  3837 int os::message_box(const char* title, const char* message) {
  3838   int i;
  3839   fdStream err(defaultStream::error_fd());
  3840   for (i = 0; i < 78; i++) err.print_raw("=");
  3841   err.cr();
  3842   err.print_raw_cr(title);
  3843   for (i = 0; i < 78; i++) err.print_raw("-");
  3844   err.cr();
  3845   err.print_raw_cr(message);
  3846   for (i = 0; i < 78; i++) err.print_raw("=");
  3847   err.cr();
  3849   char buf[16];
  3850   // Prevent process from exiting upon "read error" without consuming all CPU
  3851   while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
  3853   return buf[0] == 'y' || buf[0] == 'Y';
  3856 int os::stat(const char *path, struct stat *sbuf) {
  3857   char pathbuf[MAX_PATH];
  3858   if (strlen(path) > MAX_PATH - 1) {
  3859     errno = ENAMETOOLONG;
  3860     return -1;
  3862   os::native_path(strcpy(pathbuf, path));
  3863   return ::stat(pathbuf, sbuf);
  3866 bool os::check_heap(bool force) {
  3867   return true;
  3870 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
  3871   return ::vsnprintf(buf, count, format, args);
  3874 // Is a (classpath) directory empty?
  3875 bool os::dir_is_empty(const char* path) {
  3876   DIR *dir = NULL;
  3877   struct dirent *ptr;
  3879   dir = opendir(path);
  3880   if (dir == NULL) return true;
  3882   /* Scan the directory */
  3883   bool result = true;
  3884   char buf[sizeof(struct dirent) + MAX_PATH];
  3885   while (result && (ptr = ::readdir(dir)) != NULL) {
  3886     if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
  3887       result = false;
  3890   closedir(dir);
  3891   return result;
  3894 // This code originates from JDK's sysOpen and open64_w
  3895 // from src/solaris/hpi/src/system_md.c
  3897 #ifndef O_DELETE
  3898 #define O_DELETE 0x10000
  3899 #endif
  3901 // Open a file. Unlink the file immediately after open returns
  3902 // if the specified oflag has the O_DELETE flag set.
  3903 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
  3905 int os::open(const char *path, int oflag, int mode) {
  3907   if (strlen(path) > MAX_PATH - 1) {
  3908     errno = ENAMETOOLONG;
  3909     return -1;
  3911   int fd;
  3912   int o_delete = (oflag & O_DELETE);
  3913   oflag = oflag & ~O_DELETE;
  3915   fd = ::open(path, oflag, mode);
  3916   if (fd == -1) return -1;
  3918   //If the open succeeded, the file might still be a directory
  3920     struct stat buf;
  3921     int ret = ::fstat(fd, &buf);
  3922     int st_mode = buf.st_mode;
  3924     if (ret != -1) {
  3925       if ((st_mode & S_IFMT) == S_IFDIR) {
  3926         errno = EISDIR;
  3927         ::close(fd);
  3928         return -1;
  3930     } else {
  3931       ::close(fd);
  3932       return -1;
  3936     /*
  3937      * All file descriptors that are opened in the JVM and not
  3938      * specifically destined for a subprocess should have the
  3939      * close-on-exec flag set.  If we don't set it, then careless 3rd
  3940      * party native code might fork and exec without closing all
  3941      * appropriate file descriptors (e.g. as we do in closeDescriptors in
  3942      * UNIXProcess.c), and this in turn might:
  3944      * - cause end-of-file to fail to be detected on some file
  3945      *   descriptors, resulting in mysterious hangs, or
  3947      * - might cause an fopen in the subprocess to fail on a system
  3948      *   suffering from bug 1085341.
  3950      * (Yes, the default setting of the close-on-exec flag is a Unix
  3951      * design flaw)
  3953      * See:
  3954      * 1085341: 32-bit stdio routines should support file descriptors >255
  3955      * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
  3956      * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
  3957      */
  3958 #ifdef FD_CLOEXEC
  3960         int flags = ::fcntl(fd, F_GETFD);
  3961         if (flags != -1)
  3962             ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
  3964 #endif
  3966   if (o_delete != 0) {
  3967     ::unlink(path);
  3969   return fd;
  3973 // create binary file, rewriting existing file if required
  3974 int os::create_binary_file(const char* path, bool rewrite_existing) {
  3975   int oflags = O_WRONLY | O_CREAT;
  3976   if (!rewrite_existing) {
  3977     oflags |= O_EXCL;
  3979   return ::open(path, oflags, S_IREAD | S_IWRITE);
  3982 // return current position of file pointer
  3983 jlong os::current_file_offset(int fd) {
  3984   return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
  3987 // move file pointer to the specified offset
  3988 jlong os::seek_to_file_offset(int fd, jlong offset) {
  3989   return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
  3992 // This code originates from JDK's sysAvailable
  3993 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
  3995 int os::available(int fd, jlong *bytes) {
  3996   jlong cur, end;
  3997   int mode;
  3998   struct stat buf;
  4000   if (::fstat(fd, &buf) >= 0) {
  4001     mode = buf.st_mode;
  4002     if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
  4003       /*
  4004       * XXX: is the following call interruptible? If so, this might
  4005       * need to go through the INTERRUPT_IO() wrapper as for other
  4006       * blocking, interruptible calls in this file.
  4007       */
  4008       int n;
  4009       if (::ioctl(fd, FIONREAD, &n) >= 0) {
  4010         *bytes = n;
  4011         return 1;
  4015   if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
  4016     return 0;
  4017   } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
  4018     return 0;
  4019   } else if (::lseek(fd, cur, SEEK_SET) == -1) {
  4020     return 0;
  4022   *bytes = end - cur;
  4023   return 1;
  4026 int os::socket_available(int fd, jint *pbytes) {
  4027    if (fd < 0)
  4028      return OS_OK;
  4030    int ret;
  4032    RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
  4034    //%% note ioctl can return 0 when successful, JVM_SocketAvailable
  4035    // is expected to return 0 on failure and 1 on success to the jdk.
  4037    return (ret == OS_ERR) ? 0 : 1;
  4040 // Map a block of memory.
  4041 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
  4042                      char *addr, size_t bytes, bool read_only,
  4043                      bool allow_exec) {
  4044   int prot;
  4045   int flags;
  4047   if (read_only) {
  4048     prot = PROT_READ;
  4049     flags = MAP_SHARED;
  4050   } else {
  4051     prot = PROT_READ | PROT_WRITE;
  4052     flags = MAP_PRIVATE;
  4055   if (allow_exec) {
  4056     prot |= PROT_EXEC;
  4059   if (addr != NULL) {
  4060     flags |= MAP_FIXED;
  4063   char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
  4064                                      fd, file_offset);
  4065   if (mapped_address == MAP_FAILED) {
  4066     return NULL;
  4068   return mapped_address;
  4072 // Remap a block of memory.
  4073 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
  4074                        char *addr, size_t bytes, bool read_only,
  4075                        bool allow_exec) {
  4076   // same as map_memory() on this OS
  4077   return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
  4078                         allow_exec);
  4082 // Unmap a block of memory.
  4083 bool os::pd_unmap_memory(char* addr, size_t bytes) {
  4084   return munmap(addr, bytes) == 0;
  4087 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
  4088 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
  4089 // of a thread.
  4090 //
  4091 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
  4092 // the fast estimate available on the platform.
  4094 jlong os::current_thread_cpu_time() {
  4095 #ifdef __APPLE__
  4096   return os::thread_cpu_time(Thread::current(), true /* user + sys */);
  4097 #else
  4098   Unimplemented();
  4099   return 0;
  4100 #endif
  4103 jlong os::thread_cpu_time(Thread* thread) {
  4104 #ifdef __APPLE__
  4105   return os::thread_cpu_time(thread, true /* user + sys */);
  4106 #else
  4107   Unimplemented();
  4108   return 0;
  4109 #endif
  4112 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
  4113 #ifdef __APPLE__
  4114   return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
  4115 #else
  4116   Unimplemented();
  4117   return 0;
  4118 #endif
  4121 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
  4122 #ifdef __APPLE__
  4123   struct thread_basic_info tinfo;
  4124   mach_msg_type_number_t tcount = THREAD_INFO_MAX;
  4125   kern_return_t kr;
  4126   thread_t mach_thread;
  4128   mach_thread = thread->osthread()->thread_id();
  4129   kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
  4130   if (kr != KERN_SUCCESS)
  4131     return -1;
  4133   if (user_sys_cpu_time) {
  4134     jlong nanos;
  4135     nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
  4136     nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
  4137     return nanos;
  4138   } else {
  4139     return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
  4141 #else
  4142   Unimplemented();
  4143   return 0;
  4144 #endif
  4148 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  4149   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  4150   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  4151   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  4152   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  4155 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
  4156   info_ptr->max_value = ALL_64_BITS;       // will not wrap in less than 64 bits
  4157   info_ptr->may_skip_backward = false;     // elapsed time not wall time
  4158   info_ptr->may_skip_forward = false;      // elapsed time not wall time
  4159   info_ptr->kind = JVMTI_TIMER_TOTAL_CPU;  // user+system time is returned
  4162 bool os::is_thread_cpu_time_supported() {
  4163 #ifdef __APPLE__
  4164   return true;
  4165 #else
  4166   return false;
  4167 #endif
  4170 // System loadavg support.  Returns -1 if load average cannot be obtained.
  4171 // Bsd doesn't yet have a (official) notion of processor sets,
  4172 // so just return the system wide load average.
  4173 int os::loadavg(double loadavg[], int nelem) {
  4174   return ::getloadavg(loadavg, nelem);
  4177 void os::pause() {
  4178   char filename[MAX_PATH];
  4179   if (PauseAtStartupFile && PauseAtStartupFile[0]) {
  4180     jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
  4181   } else {
  4182     jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
  4185   int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
  4186   if (fd != -1) {
  4187     struct stat buf;
  4188     ::close(fd);
  4189     while (::stat(filename, &buf) == 0) {
  4190       (void)::poll(NULL, 0, 100);
  4192   } else {
  4193     jio_fprintf(stderr,
  4194       "Could not open pause file '%s', continuing immediately.\n", filename);
  4199 // Refer to the comments in os_solaris.cpp park-unpark.
  4200 //
  4201 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
  4202 // hang indefinitely.  For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
  4203 // For specifics regarding the bug see GLIBC BUGID 261237 :
  4204 //    http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
  4205 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
  4206 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
  4207 // is used.  (The simple C test-case provided in the GLIBC bug report manifests the
  4208 // hang).  The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
  4209 // and monitorenter when we're using 1-0 locking.  All those operations may result in
  4210 // calls to pthread_cond_timedwait().  Using LD_ASSUME_KERNEL to use an older version
  4211 // of libpthread avoids the problem, but isn't practical.
  4212 //
  4213 // Possible remedies:
  4214 //
  4215 // 1.   Establish a minimum relative wait time.  50 to 100 msecs seems to work.
  4216 //      This is palliative and probabilistic, however.  If the thread is preempted
  4217 //      between the call to compute_abstime() and pthread_cond_timedwait(), more
  4218 //      than the minimum period may have passed, and the abstime may be stale (in the
  4219 //      past) resultin in a hang.   Using this technique reduces the odds of a hang
  4220 //      but the JVM is still vulnerable, particularly on heavily loaded systems.
  4221 //
  4222 // 2.   Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
  4223 //      of the usual flag-condvar-mutex idiom.  The write side of the pipe is set
  4224 //      NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
  4225 //      reduces to poll()+read().  This works well, but consumes 2 FDs per extant
  4226 //      thread.
  4227 //
  4228 // 3.   Embargo pthread_cond_timedwait() and implement a native "chron" thread
  4229 //      that manages timeouts.  We'd emulate pthread_cond_timedwait() by enqueuing
  4230 //      a timeout request to the chron thread and then blocking via pthread_cond_wait().
  4231 //      This also works well.  In fact it avoids kernel-level scalability impediments
  4232 //      on certain platforms that don't handle lots of active pthread_cond_timedwait()
  4233 //      timers in a graceful fashion.
  4234 //
  4235 // 4.   When the abstime value is in the past it appears that control returns
  4236 //      correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
  4237 //      Subsequent timedwait/wait calls may hang indefinitely.  Given that, we
  4238 //      can avoid the problem by reinitializing the condvar -- by cond_destroy()
  4239 //      followed by cond_init() -- after all calls to pthread_cond_timedwait().
  4240 //      It may be possible to avoid reinitialization by checking the return
  4241 //      value from pthread_cond_timedwait().  In addition to reinitializing the
  4242 //      condvar we must establish the invariant that cond_signal() is only called
  4243 //      within critical sections protected by the adjunct mutex.  This prevents
  4244 //      cond_signal() from "seeing" a condvar that's in the midst of being
  4245 //      reinitialized or that is corrupt.  Sadly, this invariant obviates the
  4246 //      desirable signal-after-unlock optimization that avoids futile context switching.
  4247 //
  4248 //      I'm also concerned that some versions of NTPL might allocate an auxilliary
  4249 //      structure when a condvar is used or initialized.  cond_destroy()  would
  4250 //      release the helper structure.  Our reinitialize-after-timedwait fix
  4251 //      put excessive stress on malloc/free and locks protecting the c-heap.
  4252 //
  4253 // We currently use (4).  See the WorkAroundNTPLTimedWaitHang flag.
  4254 // It may be possible to refine (4) by checking the kernel and NTPL verisons
  4255 // and only enabling the work-around for vulnerable environments.
  4257 // utility to compute the abstime argument to timedwait:
  4258 // millis is the relative timeout time
  4259 // abstime will be the absolute timeout time
  4260 // TODO: replace compute_abstime() with unpackTime()
  4262 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
  4263   if (millis < 0)  millis = 0;
  4264   struct timeval now;
  4265   int status = gettimeofday(&now, NULL);
  4266   assert(status == 0, "gettimeofday");
  4267   jlong seconds = millis / 1000;
  4268   millis %= 1000;
  4269   if (seconds > 50000000) { // see man cond_timedwait(3T)
  4270     seconds = 50000000;
  4272   abstime->tv_sec = now.tv_sec  + seconds;
  4273   long       usec = now.tv_usec + millis * 1000;
  4274   if (usec >= 1000000) {
  4275     abstime->tv_sec += 1;
  4276     usec -= 1000000;
  4278   abstime->tv_nsec = usec * 1000;
  4279   return abstime;
  4283 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
  4284 // Conceptually TryPark() should be equivalent to park(0).
  4286 int os::PlatformEvent::TryPark() {
  4287   for (;;) {
  4288     const int v = _Event ;
  4289     guarantee ((v == 0) || (v == 1), "invariant") ;
  4290     if (Atomic::cmpxchg (0, &_Event, v) == v) return v  ;
  4294 void os::PlatformEvent::park() {       // AKA "down()"
  4295   // Invariant: Only the thread associated with the Event/PlatformEvent
  4296   // may call park().
  4297   // TODO: assert that _Assoc != NULL or _Assoc == Self
  4298   int v ;
  4299   for (;;) {
  4300       v = _Event ;
  4301       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4303   guarantee (v >= 0, "invariant") ;
  4304   if (v == 0) {
  4305      // Do this the hard way by blocking ...
  4306      int status = pthread_mutex_lock(_mutex);
  4307      assert_status(status == 0, status, "mutex_lock");
  4308      guarantee (_nParked == 0, "invariant") ;
  4309      ++ _nParked ;
  4310      while (_Event < 0) {
  4311         status = pthread_cond_wait(_cond, _mutex);
  4312         // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
  4313         // Treat this the same as if the wait was interrupted
  4314         if (status == ETIMEDOUT) { status = EINTR; }
  4315         assert_status(status == 0 || status == EINTR, status, "cond_wait");
  4317      -- _nParked ;
  4319     _Event = 0 ;
  4320      status = pthread_mutex_unlock(_mutex);
  4321      assert_status(status == 0, status, "mutex_unlock");
  4322     // Paranoia to ensure our locked and lock-free paths interact
  4323     // correctly with each other.
  4324     OrderAccess::fence();
  4326   guarantee (_Event >= 0, "invariant") ;
  4329 int os::PlatformEvent::park(jlong millis) {
  4330   guarantee (_nParked == 0, "invariant") ;
  4332   int v ;
  4333   for (;;) {
  4334       v = _Event ;
  4335       if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
  4337   guarantee (v >= 0, "invariant") ;
  4338   if (v != 0) return OS_OK ;
  4340   // We do this the hard way, by blocking the thread.
  4341   // Consider enforcing a minimum timeout value.
  4342   struct timespec abst;
  4343   compute_abstime(&abst, millis);
  4345   int ret = OS_TIMEOUT;
  4346   int status = pthread_mutex_lock(_mutex);
  4347   assert_status(status == 0, status, "mutex_lock");
  4348   guarantee (_nParked == 0, "invariant") ;
  4349   ++_nParked ;
  4351   // Object.wait(timo) will return because of
  4352   // (a) notification
  4353   // (b) timeout
  4354   // (c) thread.interrupt
  4355   //
  4356   // Thread.interrupt and object.notify{All} both call Event::set.
  4357   // That is, we treat thread.interrupt as a special case of notification.
  4358   // The underlying Solaris implementation, cond_timedwait, admits
  4359   // spurious/premature wakeups, but the JLS/JVM spec prevents the
  4360   // JVM from making those visible to Java code.  As such, we must
  4361   // filter out spurious wakeups.  We assume all ETIME returns are valid.
  4362   //
  4363   // TODO: properly differentiate simultaneous notify+interrupt.
  4364   // In that case, we should propagate the notify to another waiter.
  4366   while (_Event < 0) {
  4367     status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
  4368     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4369       pthread_cond_destroy (_cond);
  4370       pthread_cond_init (_cond, NULL) ;
  4372     assert_status(status == 0 || status == EINTR ||
  4373                   status == ETIMEDOUT,
  4374                   status, "cond_timedwait");
  4375     if (!FilterSpuriousWakeups) break ;                 // previous semantics
  4376     if (status == ETIMEDOUT) break ;
  4377     // We consume and ignore EINTR and spurious wakeups.
  4379   --_nParked ;
  4380   if (_Event >= 0) {
  4381      ret = OS_OK;
  4383   _Event = 0 ;
  4384   status = pthread_mutex_unlock(_mutex);
  4385   assert_status(status == 0, status, "mutex_unlock");
  4386   assert (_nParked == 0, "invariant") ;
  4387   // Paranoia to ensure our locked and lock-free paths interact
  4388   // correctly with each other.
  4389   OrderAccess::fence();
  4390   return ret;
  4393 void os::PlatformEvent::unpark() {
  4394   // Transitions for _Event:
  4395   //    0 :=> 1
  4396   //    1 :=> 1
  4397   //   -1 :=> either 0 or 1; must signal target thread
  4398   //          That is, we can safely transition _Event from -1 to either
  4399   //          0 or 1. Forcing 1 is slightly more efficient for back-to-back
  4400   //          unpark() calls.
  4401   // See also: "Semaphores in Plan 9" by Mullender & Cox
  4402   //
  4403   // Note: Forcing a transition from "-1" to "1" on an unpark() means
  4404   // that it will take two back-to-back park() calls for the owning
  4405   // thread to block. This has the benefit of forcing a spurious return
  4406   // from the first park() call after an unpark() call which will help
  4407   // shake out uses of park() and unpark() without condition variables.
  4409   if (Atomic::xchg(1, &_Event) >= 0) return;
  4411   // Wait for the thread associated with the event to vacate
  4412   int status = pthread_mutex_lock(_mutex);
  4413   assert_status(status == 0, status, "mutex_lock");
  4414   int AnyWaiters = _nParked;
  4415   assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
  4416   if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
  4417     AnyWaiters = 0;
  4418     pthread_cond_signal(_cond);
  4420   status = pthread_mutex_unlock(_mutex);
  4421   assert_status(status == 0, status, "mutex_unlock");
  4422   if (AnyWaiters != 0) {
  4423     status = pthread_cond_signal(_cond);
  4424     assert_status(status == 0, status, "cond_signal");
  4427   // Note that we signal() _after dropping the lock for "immortal" Events.
  4428   // This is safe and avoids a common class of  futile wakeups.  In rare
  4429   // circumstances this can cause a thread to return prematurely from
  4430   // cond_{timed}wait() but the spurious wakeup is benign and the victim will
  4431   // simply re-test the condition and re-park itself.
  4435 // JSR166
  4436 // -------------------------------------------------------
  4438 /*
  4439  * The solaris and bsd implementations of park/unpark are fairly
  4440  * conservative for now, but can be improved. They currently use a
  4441  * mutex/condvar pair, plus a a count.
  4442  * Park decrements count if > 0, else does a condvar wait.  Unpark
  4443  * sets count to 1 and signals condvar.  Only one thread ever waits
  4444  * on the condvar. Contention seen when trying to park implies that someone
  4445  * is unparking you, so don't wait. And spurious returns are fine, so there
  4446  * is no need to track notifications.
  4447  */
  4449 #define MAX_SECS 100000000
  4450 /*
  4451  * This code is common to bsd and solaris and will be moved to a
  4452  * common place in dolphin.
  4454  * The passed in time value is either a relative time in nanoseconds
  4455  * or an absolute time in milliseconds. Either way it has to be unpacked
  4456  * into suitable seconds and nanoseconds components and stored in the
  4457  * given timespec structure.
  4458  * Given time is a 64-bit value and the time_t used in the timespec is only
  4459  * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
  4460  * overflow if times way in the future are given. Further on Solaris versions
  4461  * prior to 10 there is a restriction (see cond_timedwait) that the specified
  4462  * number of seconds, in abstime, is less than current_time  + 100,000,000.
  4463  * As it will be 28 years before "now + 100000000" will overflow we can
  4464  * ignore overflow and just impose a hard-limit on seconds using the value
  4465  * of "now + 100,000,000". This places a limit on the timeout of about 3.17
  4466  * years from "now".
  4467  */
  4469 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
  4470   assert (time > 0, "convertTime");
  4472   struct timeval now;
  4473   int status = gettimeofday(&now, NULL);
  4474   assert(status == 0, "gettimeofday");
  4476   time_t max_secs = now.tv_sec + MAX_SECS;
  4478   if (isAbsolute) {
  4479     jlong secs = time / 1000;
  4480     if (secs > max_secs) {
  4481       absTime->tv_sec = max_secs;
  4483     else {
  4484       absTime->tv_sec = secs;
  4486     absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
  4488   else {
  4489     jlong secs = time / NANOSECS_PER_SEC;
  4490     if (secs >= MAX_SECS) {
  4491       absTime->tv_sec = max_secs;
  4492       absTime->tv_nsec = 0;
  4494     else {
  4495       absTime->tv_sec = now.tv_sec + secs;
  4496       absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
  4497       if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
  4498         absTime->tv_nsec -= NANOSECS_PER_SEC;
  4499         ++absTime->tv_sec; // note: this must be <= max_secs
  4503   assert(absTime->tv_sec >= 0, "tv_sec < 0");
  4504   assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
  4505   assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
  4506   assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
  4509 void Parker::park(bool isAbsolute, jlong time) {
  4510   // Ideally we'd do something useful while spinning, such
  4511   // as calling unpackTime().
  4513   // Optional fast-path check:
  4514   // Return immediately if a permit is available.
  4515   // We depend on Atomic::xchg() having full barrier semantics
  4516   // since we are doing a lock-free update to _counter.
  4517   if (Atomic::xchg(0, &_counter) > 0) return;
  4519   Thread* thread = Thread::current();
  4520   assert(thread->is_Java_thread(), "Must be JavaThread");
  4521   JavaThread *jt = (JavaThread *)thread;
  4523   // Optional optimization -- avoid state transitions if there's an interrupt pending.
  4524   // Check interrupt before trying to wait
  4525   if (Thread::is_interrupted(thread, false)) {
  4526     return;
  4529   // Next, demultiplex/decode time arguments
  4530   struct timespec absTime;
  4531   if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
  4532     return;
  4534   if (time > 0) {
  4535     unpackTime(&absTime, isAbsolute, time);
  4539   // Enter safepoint region
  4540   // Beware of deadlocks such as 6317397.
  4541   // The per-thread Parker:: mutex is a classic leaf-lock.
  4542   // In particular a thread must never block on the Threads_lock while
  4543   // holding the Parker:: mutex.  If safepoints are pending both the
  4544   // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
  4545   ThreadBlockInVM tbivm(jt);
  4547   // Don't wait if cannot get lock since interference arises from
  4548   // unblocking.  Also. check interrupt before trying wait
  4549   if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
  4550     return;
  4553   int status ;
  4554   if (_counter > 0)  { // no wait needed
  4555     _counter = 0;
  4556     status = pthread_mutex_unlock(_mutex);
  4557     assert (status == 0, "invariant") ;
  4558     // Paranoia to ensure our locked and lock-free paths interact
  4559     // correctly with each other and Java-level accesses.
  4560     OrderAccess::fence();
  4561     return;
  4564 #ifdef ASSERT
  4565   // Don't catch signals while blocked; let the running threads have the signals.
  4566   // (This allows a debugger to break into the running thread.)
  4567   sigset_t oldsigs;
  4568   sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
  4569   pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
  4570 #endif
  4572   OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
  4573   jt->set_suspend_equivalent();
  4574   // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
  4576   if (time == 0) {
  4577     status = pthread_cond_wait (_cond, _mutex) ;
  4578   } else {
  4579     status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
  4580     if (status != 0 && WorkAroundNPTLTimedWaitHang) {
  4581       pthread_cond_destroy (_cond) ;
  4582       pthread_cond_init    (_cond, NULL);
  4585   assert_status(status == 0 || status == EINTR ||
  4586                 status == ETIMEDOUT,
  4587                 status, "cond_timedwait");
  4589 #ifdef ASSERT
  4590   pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
  4591 #endif
  4593   _counter = 0 ;
  4594   status = pthread_mutex_unlock(_mutex) ;
  4595   assert_status(status == 0, status, "invariant") ;
  4596   // Paranoia to ensure our locked and lock-free paths interact
  4597   // correctly with each other and Java-level accesses.
  4598   OrderAccess::fence();
  4600   // If externally suspended while waiting, re-suspend
  4601   if (jt->handle_special_suspend_equivalent_condition()) {
  4602     jt->java_suspend_self();
  4606 void Parker::unpark() {
  4607   int s, status ;
  4608   status = pthread_mutex_lock(_mutex);
  4609   assert (status == 0, "invariant") ;
  4610   s = _counter;
  4611   _counter = 1;
  4612   if (s < 1) {
  4613      if (WorkAroundNPTLTimedWaitHang) {
  4614         status = pthread_cond_signal (_cond) ;
  4615         assert (status == 0, "invariant") ;
  4616         status = pthread_mutex_unlock(_mutex);
  4617         assert (status == 0, "invariant") ;
  4618      } else {
  4619         status = pthread_mutex_unlock(_mutex);
  4620         assert (status == 0, "invariant") ;
  4621         status = pthread_cond_signal (_cond) ;
  4622         assert (status == 0, "invariant") ;
  4624   } else {
  4625     pthread_mutex_unlock(_mutex);
  4626     assert (status == 0, "invariant") ;
  4631 /* Darwin has no "environ" in a dynamic library. */
  4632 #ifdef __APPLE__
  4633 #include <crt_externs.h>
  4634 #define environ (*_NSGetEnviron())
  4635 #else
  4636 extern char** environ;
  4637 #endif
  4639 // Run the specified command in a separate process. Return its exit value,
  4640 // or -1 on failure (e.g. can't fork a new process).
  4641 // Unlike system(), this function can be called from signal handler. It
  4642 // doesn't block SIGINT et al.
  4643 int os::fork_and_exec(char* cmd) {
  4644   const char * argv[4] = {"sh", "-c", cmd, NULL};
  4646   // fork() in BsdThreads/NPTL is not async-safe. It needs to run
  4647   // pthread_atfork handlers and reset pthread library. All we need is a
  4648   // separate process to execve. Make a direct syscall to fork process.
  4649   // On IA64 there's no fork syscall, we have to use fork() and hope for
  4650   // the best...
  4651   pid_t pid = fork();
  4653   if (pid < 0) {
  4654     // fork failed
  4655     return -1;
  4657   } else if (pid == 0) {
  4658     // child process
  4660     // execve() in BsdThreads will call pthread_kill_other_threads_np()
  4661     // first to kill every thread on the thread list. Because this list is
  4662     // not reset by fork() (see notes above), execve() will instead kill
  4663     // every thread in the parent process. We know this is the only thread
  4664     // in the new process, so make a system call directly.
  4665     // IA64 should use normal execve() from glibc to match the glibc fork()
  4666     // above.
  4667     execve("/bin/sh", (char* const*)argv, environ);
  4669     // execve failed
  4670     _exit(-1);
  4672   } else  {
  4673     // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
  4674     // care about the actual exit code, for now.
  4676     int status;
  4678     // Wait for the child process to exit.  This returns immediately if
  4679     // the child has already exited. */
  4680     while (waitpid(pid, &status, 0) < 0) {
  4681         switch (errno) {
  4682         case ECHILD: return 0;
  4683         case EINTR: break;
  4684         default: return -1;
  4688     if (WIFEXITED(status)) {
  4689        // The child exited normally; get its exit code.
  4690        return WEXITSTATUS(status);
  4691     } else if (WIFSIGNALED(status)) {
  4692        // The child exited because of a signal
  4693        // The best value to return is 0x80 + signal number,
  4694        // because that is what all Unix shells do, and because
  4695        // it allows callers to distinguish between process exit and
  4696        // process death by signal.
  4697        return 0x80 + WTERMSIG(status);
  4698     } else {
  4699        // Unknown exit code; pass it through
  4700        return status;
  4705 // is_headless_jre()
  4706 //
  4707 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
  4708 // in order to report if we are running in a headless jre
  4709 //
  4710 // Since JDK8 xawt/libmawt.so was moved into the same directory
  4711 // as libawt.so, and renamed libawt_xawt.so
  4712 //
  4713 bool os::is_headless_jre() {
  4714 #ifdef __APPLE__
  4715     // We no longer build headless-only on Mac OS X
  4716     return false;
  4717 #else
  4718     struct stat statbuf;
  4719     char buf[MAXPATHLEN];
  4720     char libmawtpath[MAXPATHLEN];
  4721     const char *xawtstr  = "/xawt/libmawt" JNI_LIB_SUFFIX;
  4722     const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
  4723     char *p;
  4725     // Get path to libjvm.so
  4726     os::jvm_path(buf, sizeof(buf));
  4728     // Get rid of libjvm.so
  4729     p = strrchr(buf, '/');
  4730     if (p == NULL) return false;
  4731     else *p = '\0';
  4733     // Get rid of client or server
  4734     p = strrchr(buf, '/');
  4735     if (p == NULL) return false;
  4736     else *p = '\0';
  4738     // check xawt/libmawt.so
  4739     strcpy(libmawtpath, buf);
  4740     strcat(libmawtpath, xawtstr);
  4741     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4743     // check libawt_xawt.so
  4744     strcpy(libmawtpath, buf);
  4745     strcat(libmawtpath, new_xawtstr);
  4746     if (::stat(libmawtpath, &statbuf) == 0) return false;
  4748     return true;
  4749 #endif
  4752 // Get the default path to the core file
  4753 // Returns the length of the string
  4754 int os::get_core_path(char* buffer, size_t bufferSize) {
  4755   int n = jio_snprintf(buffer, bufferSize, "/cores");
  4757   // Truncate if theoretical string was longer than bufferSize
  4758   n = MIN2(n, (int)bufferSize);
  4760   return n;
  4763 #ifndef PRODUCT
  4764 void TestReserveMemorySpecial_test() {
  4765   // No tests available for this platform
  4767 #endif

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