/* * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ // no precompiled headers #include "classfile/classLoader.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/vmSymbols.hpp" #include "code/icBuffer.hpp" #include "code/vtableStubs.hpp" #include "compiler/compileBroker.hpp" #include "compiler/disassembler.hpp" #include "interpreter/interpreter.hpp" #include "jvm_bsd.h" #include "memory/allocation.inline.hpp" #include "memory/filemap.hpp" #include "mutex_bsd.inline.hpp" #include "oops/oop.inline.hpp" #include "os_bsd.inline.hpp" #include "os_share_bsd.hpp" #include "prims/jniFastGetField.hpp" #include "prims/jvm.h" #include "prims/jvm_misc.hpp" #include "runtime/arguments.hpp" #include "runtime/atomic.inline.hpp" #include "runtime/extendedPC.hpp" #include "runtime/globals.hpp" #include "runtime/interfaceSupport.hpp" #include "runtime/java.hpp" #include "runtime/javaCalls.hpp" #include "runtime/mutexLocker.hpp" #include "runtime/objectMonitor.hpp" #include "runtime/orderAccess.inline.hpp" #include "runtime/osThread.hpp" #include "runtime/perfMemory.hpp" #include "runtime/sharedRuntime.hpp" #include "runtime/statSampler.hpp" #include "runtime/stubRoutines.hpp" #include "runtime/thread.inline.hpp" #include "runtime/threadCritical.hpp" #include "runtime/timer.hpp" #include "services/attachListener.hpp" #include "services/memTracker.hpp" #include "services/runtimeService.hpp" #include "utilities/decoder.hpp" #include "utilities/defaultStream.hpp" #include "utilities/events.hpp" #include "utilities/growableArray.hpp" #include "utilities/vmError.hpp" // put OS-includes here # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include # include #ifndef __APPLE__ # include #endif # include # include # include # include #if defined(__FreeBSD__) || defined(__NetBSD__) # include #endif #ifdef __APPLE__ # include // semaphore_* API # include # include # include #endif #ifndef MAP_ANONYMOUS #define MAP_ANONYMOUS MAP_ANON #endif #define MAX_PATH (2 * K) // for timer info max values which include all bits #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF) #define LARGEPAGES_BIT (1 << 6) PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC //////////////////////////////////////////////////////////////////////////////// // global variables julong os::Bsd::_physical_memory = 0; #ifdef __APPLE__ mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0}; volatile uint64_t os::Bsd::_max_abstime = 0; #else int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL; #endif pthread_t os::Bsd::_main_thread; int os::Bsd::_page_size = -1; static jlong initial_time_count=0; static int clock_tics_per_sec = 100; // For diagnostics to print a message once. see run_periodic_checks static sigset_t check_signal_done; static bool check_signals = true; static pid_t _initial_pid = 0; /* Signal number used to suspend/resume a thread */ /* do not use any signal number less than SIGSEGV, see 4355769 */ static int SR_signum = SIGUSR2; sigset_t SR_sigset; //////////////////////////////////////////////////////////////////////////////// // utility functions static int SR_initialize(); static void unpackTime(timespec* absTime, bool isAbsolute, jlong time); julong os::available_memory() { return Bsd::available_memory(); } // available here means free julong os::Bsd::available_memory() { uint64_t available = physical_memory() >> 2; #ifdef __APPLE__ mach_msg_type_number_t count = HOST_VM_INFO64_COUNT; vm_statistics64_data_t vmstat; kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64, (host_info64_t)&vmstat, &count); assert(kerr == KERN_SUCCESS, "host_statistics64 failed - check mach_host_self() and count"); if (kerr == KERN_SUCCESS) { available = vmstat.free_count * os::vm_page_size(); } #endif return available; } julong os::physical_memory() { return Bsd::physical_memory(); } //////////////////////////////////////////////////////////////////////////////// // environment support bool os::getenv(const char* name, char* buf, int len) { const char* val = ::getenv(name); if (val != NULL && strlen(val) < (size_t)len) { strcpy(buf, val); return true; } if (len > 0) buf[0] = 0; // return a null string return false; } // Return true if user is running as root. bool os::have_special_privileges() { static bool init = false; static bool privileges = false; if (!init) { privileges = (getuid() != geteuid()) || (getgid() != getegid()); init = true; } return privileges; } // Cpu architecture string #if defined(ZERO) static char cpu_arch[] = ZERO_LIBARCH; #elif defined(IA64) static char cpu_arch[] = "ia64"; #elif defined(IA32) static char cpu_arch[] = "i386"; #elif defined(AMD64) static char cpu_arch[] = "amd64"; #elif defined(ARM) static char cpu_arch[] = "arm"; #elif defined(PPC32) static char cpu_arch[] = "ppc"; #elif defined(SPARC) # ifdef _LP64 static char cpu_arch[] = "sparcv9"; # else static char cpu_arch[] = "sparc"; # endif #else #error Add appropriate cpu_arch setting #endif // Compiler variant #ifdef COMPILER2 #define COMPILER_VARIANT "server" #else #define COMPILER_VARIANT "client" #endif void os::Bsd::initialize_system_info() { int mib[2]; size_t len; int cpu_val; julong mem_val; /* get processors count via hw.ncpus sysctl */ mib[0] = CTL_HW; mib[1] = HW_NCPU; len = sizeof(cpu_val); if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) { assert(len == sizeof(cpu_val), "unexpected data size"); set_processor_count(cpu_val); } else { set_processor_count(1); // fallback } /* get physical memory via hw.memsize sysctl (hw.memsize is used * since it returns a 64 bit value) */ mib[0] = CTL_HW; #if defined (HW_MEMSIZE) // Apple mib[1] = HW_MEMSIZE; #elif defined(HW_PHYSMEM) // Most of BSD mib[1] = HW_PHYSMEM; #elif defined(HW_REALMEM) // Old FreeBSD mib[1] = HW_REALMEM; #else #error No ways to get physmem #endif len = sizeof(mem_val); if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) { assert(len == sizeof(mem_val), "unexpected data size"); _physical_memory = mem_val; } else { _physical_memory = 256*1024*1024; // fallback (XXXBSD?) } #ifdef __OpenBSD__ { // limit _physical_memory memory view on OpenBSD since // datasize rlimit restricts us anyway. struct rlimit limits; getrlimit(RLIMIT_DATA, &limits); _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur); } #endif } #ifdef __APPLE__ static const char *get_home() { const char *home_dir = ::getenv("HOME"); if ((home_dir == NULL) || (*home_dir == '\0')) { struct passwd *passwd_info = getpwuid(geteuid()); if (passwd_info != NULL) { home_dir = passwd_info->pw_dir; } } return home_dir; } #endif void os::init_system_properties_values() { // The next steps are taken in the product version: // // Obtain the JAVA_HOME value from the location of libjvm.so. // This library should be located at: // /jre/lib//{client|server}/libjvm.so. // // If "/jre/lib/" appears at the right place in the path, then we // assume libjvm.so is installed in a JDK and we use this path. // // Otherwise exit with message: "Could not create the Java virtual machine." // // The following extra steps are taken in the debugging version: // // If "/jre/lib/" does NOT appear at the right place in the path // instead of exit check for $JAVA_HOME environment variable. // // If it is defined and we are able to locate $JAVA_HOME/jre/lib/, // then we append a fake suffix "hotspot/libjvm.so" to this path so // it looks like libjvm.so is installed there // /jre/lib//hotspot/libjvm.so. // // Otherwise exit. // // Important note: if the location of libjvm.so changes this // code needs to be changed accordingly. // See ld(1): // The linker uses the following search paths to locate required // shared libraries: // 1: ... // ... // 7: The default directories, normally /lib and /usr/lib. #ifndef DEFAULT_LIBPATH #define DEFAULT_LIBPATH "/lib:/usr/lib" #endif // Base path of extensions installed on the system. #define SYS_EXT_DIR "/usr/java/packages" #define EXTENSIONS_DIR "/lib/ext" #define ENDORSED_DIR "/lib/endorsed" #ifndef __APPLE__ // Buffer that fits several sprintfs. // Note that the space for the colon and the trailing null are provided // by the nulls included by the sizeof operator. const size_t bufsize = MAX3((size_t)MAXPATHLEN, // For dll_dir & friends. (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR), // extensions dir (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); // sysclasspath, java_home, dll_dir { char *pslash; os::jvm_path(buf, bufsize); // Found the full path to libjvm.so. // Now cut the path to /jre if we can. *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. pslash = strrchr(buf, '/'); if (pslash != NULL) { *pslash = '\0'; // Get rid of /{client|server|hotspot}. } Arguments::set_dll_dir(buf); if (pslash != NULL) { pslash = strrchr(buf, '/'); if (pslash != NULL) { *pslash = '\0'; // Get rid of /. pslash = strrchr(buf, '/'); if (pslash != NULL) { *pslash = '\0'; // Get rid of /lib. } } } Arguments::set_java_home(buf); set_boot_path('/', ':'); } // Where to look for native libraries. // // Note: Due to a legacy implementation, most of the library path // is set in the launcher. This was to accomodate linking restrictions // on legacy Bsd implementations (which are no longer supported). // Eventually, all the library path setting will be done here. // // However, to prevent the proliferation of improperly built native // libraries, the new path component /usr/java/packages is added here. // Eventually, all the library path setting will be done here. { // Get the user setting of LD_LIBRARY_PATH, and prepended it. It // should always exist (until the legacy problem cited above is // addressed). const char *v = ::getenv("LD_LIBRARY_PATH"); const char *v_colon = ":"; if (v == NULL) { v = ""; v_colon = ""; } // That's +1 for the colon and +1 for the trailing '\0'. char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, strlen(v) + 1 + sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1, mtInternal); sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch); Arguments::set_library_path(ld_library_path); FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); } // Extensions directories. sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home()); Arguments::set_ext_dirs(buf); // Endorsed standards default directory. sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); Arguments::set_endorsed_dirs(buf); FREE_C_HEAP_ARRAY(char, buf, mtInternal); #else // __APPLE__ #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions" #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java" const char *user_home_dir = get_home(); // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir. size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) + sizeof(SYS_EXTENSIONS_DIRS); // Buffer that fits several sprintfs. // Note that the space for the colon and the trailing null are provided // by the nulls included by the sizeof operator. const size_t bufsize = MAX3((size_t)MAXPATHLEN, // for dll_dir & friends. (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size, // extensions dir (size_t)MAXPATHLEN + sizeof(ENDORSED_DIR)); // endorsed dir char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal); // sysclasspath, java_home, dll_dir { char *pslash; os::jvm_path(buf, bufsize); // Found the full path to libjvm.so. // Now cut the path to /jre if we can. *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so. pslash = strrchr(buf, '/'); if (pslash != NULL) { *pslash = '\0'; // Get rid of /{client|server|hotspot}. } Arguments::set_dll_dir(buf); if (pslash != NULL) { pslash = strrchr(buf, '/'); if (pslash != NULL) { *pslash = '\0'; // Get rid of /lib. } } Arguments::set_java_home(buf); set_boot_path('/', ':'); } // Where to look for native libraries. // // Note: Due to a legacy implementation, most of the library path // is set in the launcher. This was to accomodate linking restrictions // on legacy Bsd implementations (which are no longer supported). // Eventually, all the library path setting will be done here. // // However, to prevent the proliferation of improperly built native // libraries, the new path component /usr/java/packages is added here. // Eventually, all the library path setting will be done here. { // Get the user setting of LD_LIBRARY_PATH, and prepended it. It // should always exist (until the legacy problem cited above is // addressed). // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code // can specify a directory inside an app wrapper const char *l = ::getenv("JAVA_LIBRARY_PATH"); const char *l_colon = ":"; if (l == NULL) { l = ""; l_colon = ""; } const char *v = ::getenv("DYLD_LIBRARY_PATH"); const char *v_colon = ":"; if (v == NULL) { v = ""; v_colon = ""; } // Apple's Java6 has "." at the beginning of java.library.path. // OpenJDK on Windows has "." at the end of java.library.path. // OpenJDK on Linux and Solaris don't have "." in java.library.path // at all. To ease the transition from Apple's Java6 to OpenJDK7, // "." is appended to the end of java.library.path. Yes, this // could cause a change in behavior, but Apple's Java6 behavior // can be achieved by putting "." at the beginning of the // JAVA_LIBRARY_PATH environment variable. char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char, strlen(v) + 1 + strlen(l) + 1 + system_ext_size + 3, mtInternal); sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.", v, v_colon, l, l_colon, user_home_dir); Arguments::set_library_path(ld_library_path); FREE_C_HEAP_ARRAY(char, ld_library_path, mtInternal); } // Extensions directories. // // Note that the space for the colon and the trailing null are provided // by the nulls included by the sizeof operator (so actually one byte more // than necessary is allocated). sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home()); Arguments::set_ext_dirs(buf); // Endorsed standards default directory. sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home()); Arguments::set_endorsed_dirs(buf); FREE_C_HEAP_ARRAY(char, buf, mtInternal); #undef SYS_EXTENSIONS_DIR #undef SYS_EXTENSIONS_DIRS #endif // __APPLE__ #undef SYS_EXT_DIR #undef EXTENSIONS_DIR #undef ENDORSED_DIR } //////////////////////////////////////////////////////////////////////////////// // breakpoint support void os::breakpoint() { BREAKPOINT; } extern "C" void breakpoint() { // use debugger to set breakpoint here } //////////////////////////////////////////////////////////////////////////////// // signal support debug_only(static bool signal_sets_initialized = false); static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs; bool os::Bsd::is_sig_ignored(int sig) { struct sigaction oact; sigaction(sig, (struct sigaction*)NULL, &oact); void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction) : CAST_FROM_FN_PTR(void*, oact.sa_handler); if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) return true; else return false; } void os::Bsd::signal_sets_init() { // Should also have an assertion stating we are still single-threaded. assert(!signal_sets_initialized, "Already initialized"); // Fill in signals that are necessarily unblocked for all threads in // the VM. Currently, we unblock the following signals: // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden // by -Xrs (=ReduceSignalUsage)); // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all // other threads. The "ReduceSignalUsage" boolean tells us not to alter // the dispositions or masks wrt these signals. // Programs embedding the VM that want to use the above signals for their // own purposes must, at this time, use the "-Xrs" option to prevent // interference with shutdown hooks and BREAK_SIGNAL thread dumping. // (See bug 4345157, and other related bugs). // In reality, though, unblocking these signals is really a nop, since // these signals are not blocked by default. sigemptyset(&unblocked_sigs); sigemptyset(&allowdebug_blocked_sigs); sigaddset(&unblocked_sigs, SIGILL); sigaddset(&unblocked_sigs, SIGSEGV); sigaddset(&unblocked_sigs, SIGBUS); sigaddset(&unblocked_sigs, SIGFPE); sigaddset(&unblocked_sigs, SR_signum); if (!ReduceSignalUsage) { if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) { sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL); sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL); } if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) { sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL); sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL); } if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) { sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL); sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL); } } // Fill in signals that are blocked by all but the VM thread. sigemptyset(&vm_sigs); if (!ReduceSignalUsage) sigaddset(&vm_sigs, BREAK_SIGNAL); debug_only(signal_sets_initialized = true); } // These are signals that are unblocked while a thread is running Java. // (For some reason, they get blocked by default.) sigset_t* os::Bsd::unblocked_signals() { assert(signal_sets_initialized, "Not initialized"); return &unblocked_sigs; } // These are the signals that are blocked while a (non-VM) thread is // running Java. Only the VM thread handles these signals. sigset_t* os::Bsd::vm_signals() { assert(signal_sets_initialized, "Not initialized"); return &vm_sigs; } // These are signals that are blocked during cond_wait to allow debugger in sigset_t* os::Bsd::allowdebug_blocked_signals() { assert(signal_sets_initialized, "Not initialized"); return &allowdebug_blocked_sigs; } void os::Bsd::hotspot_sigmask(Thread* thread) { //Save caller's signal mask before setting VM signal mask sigset_t caller_sigmask; pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask); OSThread* osthread = thread->osthread(); osthread->set_caller_sigmask(caller_sigmask); pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL); if (!ReduceSignalUsage) { if (thread->is_VM_thread()) { // Only the VM thread handles BREAK_SIGNAL ... pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL); } else { // ... all other threads block BREAK_SIGNAL pthread_sigmask(SIG_BLOCK, vm_signals(), NULL); } } } ////////////////////////////////////////////////////////////////////////////// // create new thread // check if it's safe to start a new thread static bool _thread_safety_check(Thread* thread) { return true; } #ifdef __APPLE__ // library handle for calling objc_registerThreadWithCollector() // without static linking to the libobjc library #define OBJC_LIB "/usr/lib/libobjc.dylib" #define OBJC_GCREGISTER "objc_registerThreadWithCollector" typedef void (*objc_registerThreadWithCollector_t)(); extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction; objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL; #endif #ifdef __APPLE__ static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) { // Additional thread_id used to correlate threads in SA thread_identifier_info_data_t m_ident_info; mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT; thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO, (thread_info_t) &m_ident_info, &count); return m_ident_info.thread_id; } #endif // Thread start routine for all newly created threads static void *java_start(Thread *thread) { // Try to randomize the cache line index of hot stack frames. // This helps when threads of the same stack traces evict each other's // cache lines. The threads can be either from the same JVM instance, or // from different JVM instances. The benefit is especially true for // processors with hyperthreading technology. static int counter = 0; int pid = os::current_process_id(); alloca(((pid ^ counter++) & 7) * 128); ThreadLocalStorage::set_thread(thread); OSThread* osthread = thread->osthread(); Monitor* sync = osthread->startThread_lock(); // non floating stack BsdThreads needs extra check, see above if (!_thread_safety_check(thread)) { // notify parent thread MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); osthread->set_state(ZOMBIE); sync->notify_all(); return NULL; } osthread->set_thread_id(os::Bsd::gettid()); #ifdef __APPLE__ uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); guarantee(unique_thread_id != 0, "unique thread id was not found"); osthread->set_unique_thread_id(unique_thread_id); #endif // initialize signal mask for this thread os::Bsd::hotspot_sigmask(thread); // initialize floating point control register os::Bsd::init_thread_fpu_state(); #ifdef __APPLE__ // register thread with objc gc if (objc_registerThreadWithCollectorFunction != NULL) { objc_registerThreadWithCollectorFunction(); } #endif // handshaking with parent thread { MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag); // notify parent thread osthread->set_state(INITIALIZED); sync->notify_all(); // wait until os::start_thread() while (osthread->get_state() == INITIALIZED) { sync->wait(Mutex::_no_safepoint_check_flag); } } // call one more level start routine thread->run(); return 0; } bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) { assert(thread->osthread() == NULL, "caller responsible"); // Allocate the OSThread object OSThread* osthread = new OSThread(NULL, NULL); if (osthread == NULL) { return false; } // set the correct thread state osthread->set_thread_type(thr_type); // Initial state is ALLOCATED but not INITIALIZED osthread->set_state(ALLOCATED); thread->set_osthread(osthread); // init thread attributes pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); // stack size if (os::Bsd::supports_variable_stack_size()) { // calculate stack size if it's not specified by caller if (stack_size == 0) { stack_size = os::Bsd::default_stack_size(thr_type); switch (thr_type) { case os::java_thread: // Java threads use ThreadStackSize which default value can be // changed with the flag -Xss assert(JavaThread::stack_size_at_create() > 0, "this should be set"); stack_size = JavaThread::stack_size_at_create(); break; case os::compiler_thread: if (CompilerThreadStackSize > 0) { stack_size = (size_t)(CompilerThreadStackSize * K); break; } // else fall through: // use VMThreadStackSize if CompilerThreadStackSize is not defined case os::vm_thread: case os::pgc_thread: case os::cgc_thread: case os::watcher_thread: if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K); break; } } stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed); pthread_attr_setstacksize(&attr, stack_size); } else { // let pthread_create() pick the default value. } ThreadState state; { pthread_t tid; int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread); pthread_attr_destroy(&attr); if (ret != 0) { if (PrintMiscellaneous && (Verbose || WizardMode)) { perror("pthread_create()"); } // Need to clean up stuff we've allocated so far thread->set_osthread(NULL); delete osthread; return false; } // Store pthread info into the OSThread osthread->set_pthread_id(tid); // Wait until child thread is either initialized or aborted { Monitor* sync_with_child = osthread->startThread_lock(); MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); while ((state = osthread->get_state()) == ALLOCATED) { sync_with_child->wait(Mutex::_no_safepoint_check_flag); } } } // Aborted due to thread limit being reached if (state == ZOMBIE) { thread->set_osthread(NULL); delete osthread; return false; } // The thread is returned suspended (in state INITIALIZED), // and is started higher up in the call chain assert(state == INITIALIZED, "race condition"); return true; } ///////////////////////////////////////////////////////////////////////////// // attach existing thread // bootstrap the main thread bool os::create_main_thread(JavaThread* thread) { assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread"); return create_attached_thread(thread); } bool os::create_attached_thread(JavaThread* thread) { #ifdef ASSERT thread->verify_not_published(); #endif // Allocate the OSThread object OSThread* osthread = new OSThread(NULL, NULL); if (osthread == NULL) { return false; } osthread->set_thread_id(os::Bsd::gettid()); // Store pthread info into the OSThread #ifdef __APPLE__ uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id()); guarantee(unique_thread_id != 0, "just checking"); osthread->set_unique_thread_id(unique_thread_id); #endif osthread->set_pthread_id(::pthread_self()); // initialize floating point control register os::Bsd::init_thread_fpu_state(); // Initial thread state is RUNNABLE osthread->set_state(RUNNABLE); thread->set_osthread(osthread); // initialize signal mask for this thread // and save the caller's signal mask os::Bsd::hotspot_sigmask(thread); return true; } void os::pd_start_thread(Thread* thread) { OSThread * osthread = thread->osthread(); assert(osthread->get_state() != INITIALIZED, "just checking"); Monitor* sync_with_child = osthread->startThread_lock(); MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag); sync_with_child->notify(); } // Free Bsd resources related to the OSThread void os::free_thread(OSThread* osthread) { assert(osthread != NULL, "osthread not set"); if (Thread::current()->osthread() == osthread) { // Restore caller's signal mask sigset_t sigmask = osthread->caller_sigmask(); pthread_sigmask(SIG_SETMASK, &sigmask, NULL); } delete osthread; } ////////////////////////////////////////////////////////////////////////////// // thread local storage // Restore the thread pointer if the destructor is called. This is in case // someone from JNI code sets up a destructor with pthread_key_create to run // detachCurrentThread on thread death. Unless we restore the thread pointer we // will hang or crash. When detachCurrentThread is called the key will be set // to null and we will not be called again. If detachCurrentThread is never // called we could loop forever depending on the pthread implementation. static void restore_thread_pointer(void* p) { Thread* thread = (Thread*) p; os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread); } int os::allocate_thread_local_storage() { pthread_key_t key; int rslt = pthread_key_create(&key, restore_thread_pointer); assert(rslt == 0, "cannot allocate thread local storage"); return (int)key; } // Note: This is currently not used by VM, as we don't destroy TLS key // on VM exit. void os::free_thread_local_storage(int index) { int rslt = pthread_key_delete((pthread_key_t)index); assert(rslt == 0, "invalid index"); } void os::thread_local_storage_at_put(int index, void* value) { int rslt = pthread_setspecific((pthread_key_t)index, value); assert(rslt == 0, "pthread_setspecific failed"); } extern "C" Thread* get_thread() { return ThreadLocalStorage::thread(); } //////////////////////////////////////////////////////////////////////////////// // time support // Time since start-up in seconds to a fine granularity. // Used by VMSelfDestructTimer and the MemProfiler. double os::elapsedTime() { return ((double)os::elapsed_counter()) / os::elapsed_frequency(); } jlong os::elapsed_counter() { return javaTimeNanos() - initial_time_count; } jlong os::elapsed_frequency() { return NANOSECS_PER_SEC; // nanosecond resolution } bool os::supports_vtime() { return true; } bool os::enable_vtime() { return false; } bool os::vtime_enabled() { return false; } double os::elapsedVTime() { // better than nothing, but not much return elapsedTime(); } jlong os::javaTimeMillis() { timeval time; int status = gettimeofday(&time, NULL); assert(status != -1, "bsd error"); return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000); } #ifndef __APPLE__ #ifndef CLOCK_MONOTONIC #define CLOCK_MONOTONIC (1) #endif #endif #ifdef __APPLE__ void os::Bsd::clock_init() { mach_timebase_info(&_timebase_info); } #else void os::Bsd::clock_init() { struct timespec res; struct timespec tp; if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 && ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) { // yes, monotonic clock is supported _clock_gettime = ::clock_gettime; } } #endif #ifdef __APPLE__ jlong os::javaTimeNanos() { const uint64_t tm = mach_absolute_time(); const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom; const uint64_t prev = Bsd::_max_abstime; if (now <= prev) { return prev; // same or retrograde time; } const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev); assert(obsv >= prev, "invariant"); // Monotonicity // If the CAS succeeded then we're done and return "now". // If the CAS failed and the observed value "obsv" is >= now then // we should return "obsv". If the CAS failed and now > obsv > prv then // some other thread raced this thread and installed a new value, in which case // we could either (a) retry the entire operation, (b) retry trying to install now // or (c) just return obsv. We use (c). No loop is required although in some cases // we might discard a higher "now" value in deference to a slightly lower but freshly // installed obsv value. That's entirely benign -- it admits no new orderings compared // to (a) or (b) -- and greatly reduces coherence traffic. // We might also condition (c) on the magnitude of the delta between obsv and now. // Avoiding excessive CAS operations to hot RW locations is critical. // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate return (prev == obsv) ? now : obsv; } #else // __APPLE__ jlong os::javaTimeNanos() { if (os::supports_monotonic_clock()) { struct timespec tp; int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp); assert(status == 0, "gettime error"); jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec); return result; } else { timeval time; int status = gettimeofday(&time, NULL); assert(status != -1, "bsd error"); jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec); return 1000 * usecs; } } #endif // __APPLE__ void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) { if (os::supports_monotonic_clock()) { info_ptr->max_value = ALL_64_BITS; // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past info_ptr->may_skip_backward = false; // not subject to resetting or drifting info_ptr->may_skip_forward = false; // not subject to resetting or drifting } else { // gettimeofday - based on time in seconds since the Epoch thus does not wrap info_ptr->max_value = ALL_64_BITS; // gettimeofday is a real time clock so it skips info_ptr->may_skip_backward = true; info_ptr->may_skip_forward = true; } info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time } // Return the real, user, and system times in seconds from an // arbitrary fixed point in the past. bool os::getTimesSecs(double* process_real_time, double* process_user_time, double* process_system_time) { struct tms ticks; clock_t real_ticks = times(&ticks); if (real_ticks == (clock_t) (-1)) { return false; } else { double ticks_per_second = (double) clock_tics_per_sec; *process_user_time = ((double) ticks.tms_utime) / ticks_per_second; *process_system_time = ((double) ticks.tms_stime) / ticks_per_second; *process_real_time = ((double) real_ticks) / ticks_per_second; return true; } } char * os::local_time_string(char *buf, size_t buflen) { struct tm t; time_t long_time; time(&long_time); localtime_r(&long_time, &t); jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d", t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec); return buf; } struct tm* os::localtime_pd(const time_t* clock, struct tm* res) { return localtime_r(clock, res); } //////////////////////////////////////////////////////////////////////////////// // runtime exit support // Note: os::shutdown() might be called very early during initialization, or // called from signal handler. Before adding something to os::shutdown(), make // sure it is async-safe and can handle partially initialized VM. void os::shutdown() { // allow PerfMemory to attempt cleanup of any persistent resources perfMemory_exit(); // needs to remove object in file system AttachListener::abort(); // flush buffered output, finish log files ostream_abort(); // Check for abort hook abort_hook_t abort_hook = Arguments::abort_hook(); if (abort_hook != NULL) { abort_hook(); } } // Note: os::abort() might be called very early during initialization, or // called from signal handler. Before adding something to os::abort(), make // sure it is async-safe and can handle partially initialized VM. void os::abort(bool dump_core) { os::shutdown(); if (dump_core) { #ifndef PRODUCT fdStream out(defaultStream::output_fd()); out.print_raw("Current thread is "); char buf[16]; jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id()); out.print_raw_cr(buf); out.print_raw_cr("Dumping core ..."); #endif ::abort(); // dump core } ::exit(1); } // Die immediately, no exit hook, no abort hook, no cleanup. void os::die() { // _exit() on BsdThreads only kills current thread ::abort(); } // This method is a copy of JDK's sysGetLastErrorString // from src/solaris/hpi/src/system_md.c size_t os::lasterror(char *buf, size_t len) { if (errno == 0) return 0; const char *s = ::strerror(errno); size_t n = ::strlen(s); if (n >= len) { n = len - 1; } ::strncpy(buf, s, n); buf[n] = '\0'; return n; } // Information of current thread in variety of formats pid_t os::Bsd::gettid() { int retval = -1; #ifdef __APPLE__ //XNU kernel // despite the fact mach port is actually not a thread id use it // instead of syscall(SYS_thread_selfid) as it certainly fits to u4 retval = ::pthread_mach_thread_np(::pthread_self()); guarantee(retval != 0, "just checking"); return retval; #elif __FreeBSD__ retval = syscall(SYS_thr_self); #elif __OpenBSD__ retval = syscall(SYS_getthrid); #elif __NetBSD__ retval = (pid_t) syscall(SYS__lwp_self); #endif if (retval == -1) { return getpid(); } } intx os::current_thread_id() { #ifdef __APPLE__ return (intx)::pthread_mach_thread_np(::pthread_self()); #else return (intx)::pthread_self(); #endif } int os::current_process_id() { // Under the old bsd thread library, bsd gives each thread // its own process id. Because of this each thread will return // a different pid if this method were to return the result // of getpid(2). Bsd provides no api that returns the pid // of the launcher thread for the vm. This implementation // returns a unique pid, the pid of the launcher thread // that starts the vm 'process'. // Under the NPTL, getpid() returns the same pid as the // launcher thread rather than a unique pid per thread. // Use gettid() if you want the old pre NPTL behaviour. // if you are looking for the result of a call to getpid() that // returns a unique pid for the calling thread, then look at the // OSThread::thread_id() method in osThread_bsd.hpp file return (int)(_initial_pid ? _initial_pid : getpid()); } // DLL functions #define JNI_LIB_PREFIX "lib" #ifdef __APPLE__ #define JNI_LIB_SUFFIX ".dylib" #else #define JNI_LIB_SUFFIX ".so" #endif const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; } // This must be hard coded because it's the system's temporary // directory not the java application's temp directory, ala java.io.tmpdir. #ifdef __APPLE__ // macosx has a secure per-user temporary directory char temp_path_storage[PATH_MAX]; const char* os::get_temp_directory() { static char *temp_path = NULL; if (temp_path == NULL) { int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX); if (pathSize == 0 || pathSize > PATH_MAX) { strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage)); } temp_path = temp_path_storage; } return temp_path; } #else /* __APPLE__ */ const char* os::get_temp_directory() { return "/tmp"; } #endif /* __APPLE__ */ static bool file_exists(const char* filename) { struct stat statbuf; if (filename == NULL || strlen(filename) == 0) { return false; } return os::stat(filename, &statbuf) == 0; } bool os::dll_build_name(char* buffer, size_t buflen, const char* pname, const char* fname) { bool retval = false; // Copied from libhpi const size_t pnamelen = pname ? strlen(pname) : 0; // Return error on buffer overflow. if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) { return retval; } if (pnamelen == 0) { snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname); retval = true; } else if (strchr(pname, *os::path_separator()) != NULL) { int n; char** pelements = split_path(pname, &n); if (pelements == NULL) { return false; } for (int i = 0; i < n; i++) { // Really shouldn't be NULL, but check can't hurt if (pelements[i] == NULL || strlen(pelements[i]) == 0) { continue; // skip the empty path values } snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pelements[i], fname); if (file_exists(buffer)) { retval = true; break; } } // release the storage for (int i = 0; i < n; i++) { if (pelements[i] != NULL) { FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal); } } if (pelements != NULL) { FREE_C_HEAP_ARRAY(char*, pelements, mtInternal); } } else { snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname); retval = true; } return retval; } // check if addr is inside libjvm.so bool os::address_is_in_vm(address addr) { static address libjvm_base_addr; Dl_info dlinfo; if (libjvm_base_addr == NULL) { if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) { libjvm_base_addr = (address)dlinfo.dli_fbase; } assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm"); } if (dladdr((void *)addr, &dlinfo) != 0) { if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true; } return false; } #define MACH_MAXSYMLEN 256 bool os::dll_address_to_function_name(address addr, char *buf, int buflen, int *offset) { // buf is not optional, but offset is optional assert(buf != NULL, "sanity check"); Dl_info dlinfo; char localbuf[MACH_MAXSYMLEN]; if (dladdr((void*)addr, &dlinfo) != 0) { // see if we have a matching symbol if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) { if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) { jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname); } if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr; return true; } // no matching symbol so try for just file info if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) { if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase), buf, buflen, offset, dlinfo.dli_fname)) { return true; } } // Handle non-dynamic manually: if (dlinfo.dli_fbase != NULL && Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) { if (!Decoder::demangle(localbuf, buf, buflen)) { jio_snprintf(buf, buflen, "%s", localbuf); } return true; } } buf[0] = '\0'; if (offset != NULL) *offset = -1; return false; } // ported from solaris version bool os::dll_address_to_library_name(address addr, char* buf, int buflen, int* offset) { // buf is not optional, but offset is optional assert(buf != NULL, "sanity check"); Dl_info dlinfo; if (dladdr((void*)addr, &dlinfo) != 0) { if (dlinfo.dli_fname != NULL) { jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname); } if (dlinfo.dli_fbase != NULL && offset != NULL) { *offset = addr - (address)dlinfo.dli_fbase; } return true; } buf[0] = '\0'; if (offset) *offset = -1; return false; } // Loads .dll/.so and // in case of error it checks if .dll/.so was built for the // same architecture as Hotspot is running on #ifdef __APPLE__ void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { void * result= ::dlopen(filename, RTLD_LAZY); if (result != NULL) { // Successful loading return result; } // Read system error message into ebuf ::strncpy(ebuf, ::dlerror(), ebuflen-1); ebuf[ebuflen-1]='\0'; return NULL; } #else void * os::dll_load(const char *filename, char *ebuf, int ebuflen) { void * result= ::dlopen(filename, RTLD_LAZY); if (result != NULL) { // Successful loading return result; } Elf32_Ehdr elf_head; // Read system error message into ebuf // It may or may not be overwritten below ::strncpy(ebuf, ::dlerror(), ebuflen-1); ebuf[ebuflen-1]='\0'; int diag_msg_max_length=ebuflen-strlen(ebuf); char* diag_msg_buf=ebuf+strlen(ebuf); if (diag_msg_max_length==0) { // No more space in ebuf for additional diagnostics message return NULL; } int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK); if (file_descriptor < 0) { // Can't open library, report dlerror() message return NULL; } bool failed_to_read_elf_head= (sizeof(elf_head)!= (::read(file_descriptor, &elf_head,sizeof(elf_head)))); ::close(file_descriptor); if (failed_to_read_elf_head) { // file i/o error - report dlerror() msg return NULL; } typedef struct { Elf32_Half code; // Actual value as defined in elf.h Elf32_Half compat_class; // Compatibility of archs at VM's sense char elf_class; // 32 or 64 bit char endianess; // MSB or LSB char* name; // String representation } arch_t; #ifndef EM_486 #define EM_486 6 /* Intel 80486 */ #endif #ifndef EM_MIPS_RS3_LE #define EM_MIPS_RS3_LE 10 /* MIPS */ #endif #ifndef EM_PPC64 #define EM_PPC64 21 /* PowerPC64 */ #endif #ifndef EM_S390 #define EM_S390 22 /* IBM System/390 */ #endif #ifndef EM_IA_64 #define EM_IA_64 50 /* HP/Intel IA-64 */ #endif #ifndef EM_X86_64 #define EM_X86_64 62 /* AMD x86-64 */ #endif static const arch_t arch_array[]={ {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"}, {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"}, {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"}, {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"}, {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"}, {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"}, {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"}, {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"}, {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"}, {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"}, {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"}, {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"}, {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"}, {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"} }; #if (defined IA32) static Elf32_Half running_arch_code=EM_386; #elif (defined AMD64) static Elf32_Half running_arch_code=EM_X86_64; #elif (defined IA64) static Elf32_Half running_arch_code=EM_IA_64; #elif (defined __sparc) && (defined _LP64) static Elf32_Half running_arch_code=EM_SPARCV9; #elif (defined __sparc) && (!defined _LP64) static Elf32_Half running_arch_code=EM_SPARC; #elif (defined __powerpc64__) static Elf32_Half running_arch_code=EM_PPC64; #elif (defined __powerpc__) static Elf32_Half running_arch_code=EM_PPC; #elif (defined ARM) static Elf32_Half running_arch_code=EM_ARM; #elif (defined S390) static Elf32_Half running_arch_code=EM_S390; #elif (defined ALPHA) static Elf32_Half running_arch_code=EM_ALPHA; #elif (defined MIPSEL) static Elf32_Half running_arch_code=EM_MIPS_RS3_LE; #elif (defined PARISC) static Elf32_Half running_arch_code=EM_PARISC; #elif (defined MIPS) static Elf32_Half running_arch_code=EM_MIPS; #elif (defined M68K) static Elf32_Half running_arch_code=EM_68K; #else #error Method os::dll_load requires that one of following is defined:\ IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K #endif // Identify compatability class for VM's architecture and library's architecture // Obtain string descriptions for architectures arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL}; int running_arch_index=-1; for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) { if (running_arch_code == arch_array[i].code) { running_arch_index = i; } if (lib_arch.code == arch_array[i].code) { lib_arch.compat_class = arch_array[i].compat_class; lib_arch.name = arch_array[i].name; } } assert(running_arch_index != -1, "Didn't find running architecture code (running_arch_code) in arch_array"); if (running_arch_index == -1) { // Even though running architecture detection failed // we may still continue with reporting dlerror() message return NULL; } if (lib_arch.endianess != arch_array[running_arch_index].endianess) { ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)"); return NULL; } #ifndef S390 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) { ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)"); return NULL; } #endif // !S390 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) { if (lib_arch.name!=NULL) { ::snprintf(diag_msg_buf, diag_msg_max_length-1, " (Possible cause: can't load %s-bit .so on a %s-bit platform)", lib_arch.name, arch_array[running_arch_index].name); } else { ::snprintf(diag_msg_buf, diag_msg_max_length-1, " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)", lib_arch.code, arch_array[running_arch_index].name); } } return NULL; } #endif /* !__APPLE__ */ void* os::get_default_process_handle() { #ifdef __APPLE__ // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY // to avoid finding unexpected symbols on second (or later) // loads of a library. return (void*)::dlopen(NULL, RTLD_FIRST); #else return (void*)::dlopen(NULL, RTLD_LAZY); #endif } // XXX: Do we need a lock around this as per Linux? void* os::dll_lookup(void* handle, const char* name) { return dlsym(handle, name); } static bool _print_ascii_file(const char* filename, outputStream* st) { int fd = ::open(filename, O_RDONLY); if (fd == -1) { return false; } char buf[32]; int bytes; while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) { st->print_raw(buf, bytes); } ::close(fd); return true; } void os::print_dll_info(outputStream *st) { st->print_cr("Dynamic libraries:"); #ifdef RTLD_DI_LINKMAP Dl_info dli; void *handle; Link_map *map; Link_map *p; if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 || dli.dli_fname == NULL) { st->print_cr("Error: Cannot print dynamic libraries."); return; } handle = dlopen(dli.dli_fname, RTLD_LAZY); if (handle == NULL) { st->print_cr("Error: Cannot print dynamic libraries."); return; } dlinfo(handle, RTLD_DI_LINKMAP, &map); if (map == NULL) { st->print_cr("Error: Cannot print dynamic libraries."); return; } while (map->l_prev != NULL) map = map->l_prev; while (map != NULL) { st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name); map = map->l_next; } dlclose(handle); #elif defined(__APPLE__) for (uint32_t i = 1; i < _dyld_image_count(); i++) { st->print_cr(PTR_FORMAT " \t%s", _dyld_get_image_header(i), _dyld_get_image_name(i)); } #else st->print_cr("Error: Cannot print dynamic libraries."); #endif } void os::print_os_info_brief(outputStream* st) { st->print("Bsd"); os::Posix::print_uname_info(st); } void os::print_os_info(outputStream* st) { st->print("OS:"); st->print("Bsd"); os::Posix::print_uname_info(st); os::Posix::print_rlimit_info(st); os::Posix::print_load_average(st); } void os::pd_print_cpu_info(outputStream* st) { // Nothing to do for now. } void os::print_memory_info(outputStream* st) { st->print("Memory:"); st->print(" %dk page", os::vm_page_size()>>10); st->print(", physical " UINT64_FORMAT "k", os::physical_memory() >> 10); st->print("(" UINT64_FORMAT "k free)", os::available_memory() >> 10); st->cr(); // meminfo st->print("\n/proc/meminfo:\n"); _print_ascii_file("/proc/meminfo", st); st->cr(); } void os::print_siginfo(outputStream* st, void* siginfo) { const siginfo_t* si = (const siginfo_t*)siginfo; os::Posix::print_siginfo_brief(st, si); if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) && UseSharedSpaces) { FileMapInfo* mapinfo = FileMapInfo::current_info(); if (mapinfo->is_in_shared_space(si->si_addr)) { st->print("\n\nError accessing class data sharing archive." \ " Mapped file inaccessible during execution, " \ " possible disk/network problem."); } } st->cr(); } static void print_signal_handler(outputStream* st, int sig, char* buf, size_t buflen); void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) { st->print_cr("Signal Handlers:"); print_signal_handler(st, SIGSEGV, buf, buflen); print_signal_handler(st, SIGBUS , buf, buflen); print_signal_handler(st, SIGFPE , buf, buflen); print_signal_handler(st, SIGPIPE, buf, buflen); print_signal_handler(st, SIGXFSZ, buf, buflen); print_signal_handler(st, SIGILL , buf, buflen); print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen); print_signal_handler(st, SR_signum, buf, buflen); print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen); print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen); print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen); print_signal_handler(st, BREAK_SIGNAL, buf, buflen); } static char saved_jvm_path[MAXPATHLEN] = {0}; // Find the full path to the current module, libjvm void os::jvm_path(char *buf, jint buflen) { // Error checking. if (buflen < MAXPATHLEN) { assert(false, "must use a large-enough buffer"); buf[0] = '\0'; return; } // Lazy resolve the path to current module. if (saved_jvm_path[0] != 0) { strcpy(buf, saved_jvm_path); return; } char dli_fname[MAXPATHLEN]; bool ret = dll_address_to_library_name( CAST_FROM_FN_PTR(address, os::jvm_path), dli_fname, sizeof(dli_fname), NULL); assert(ret, "cannot locate libjvm"); char *rp = NULL; if (ret && dli_fname[0] != '\0') { rp = realpath(dli_fname, buf); } if (rp == NULL) return; if (Arguments::sun_java_launcher_is_altjvm()) { // Support for the java launcher's '-XXaltjvm=' option. Typical // value for buf is "/jre/lib///libjvm.so" // or "/jre/lib//libjvm.dylib". If "/jre/lib/" // appears at the right place in the string, then assume we are // installed in a JDK and we're done. Otherwise, check for a // JAVA_HOME environment variable and construct a path to the JVM // being overridden. const char *p = buf + strlen(buf) - 1; for (int count = 0; p > buf && count < 5; ++count) { for (--p; p > buf && *p != '/'; --p) /* empty */ ; } if (strncmp(p, "/jre/lib/", 9) != 0) { // Look for JAVA_HOME in the environment. char* java_home_var = ::getenv("JAVA_HOME"); if (java_home_var != NULL && java_home_var[0] != 0) { char* jrelib_p; int len; // Check the current module name "libjvm" p = strrchr(buf, '/'); assert(strstr(p, "/libjvm") == p, "invalid library name"); rp = realpath(java_home_var, buf); if (rp == NULL) return; // determine if this is a legacy image or modules image // modules image doesn't have "jre" subdirectory len = strlen(buf); assert(len < buflen, "Ran out of buffer space"); jrelib_p = buf + len; // Add the appropriate library subdir snprintf(jrelib_p, buflen-len, "/jre/lib"); if (0 != access(buf, F_OK)) { snprintf(jrelib_p, buflen-len, "/lib"); } // Add the appropriate client or server subdir len = strlen(buf); jrelib_p = buf + len; snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT); if (0 != access(buf, F_OK)) { snprintf(jrelib_p, buflen-len, "%s", ""); } // If the path exists within JAVA_HOME, add the JVM library name // to complete the path to JVM being overridden. Otherwise fallback // to the path to the current library. if (0 == access(buf, F_OK)) { // Use current module name "libjvm" len = strlen(buf); snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX); } else { // Fall back to path of current library rp = realpath(dli_fname, buf); if (rp == NULL) return; } } } } strncpy(saved_jvm_path, buf, MAXPATHLEN); } void os::print_jni_name_prefix_on(outputStream* st, int args_size) { // no prefix required, not even "_" } void os::print_jni_name_suffix_on(outputStream* st, int args_size) { // no suffix required } //////////////////////////////////////////////////////////////////////////////// // sun.misc.Signal support static volatile jint sigint_count = 0; static void UserHandler(int sig, void *siginfo, void *context) { // 4511530 - sem_post is serialized and handled by the manager thread. When // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We // don't want to flood the manager thread with sem_post requests. if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) return; // Ctrl-C is pressed during error reporting, likely because the error // handler fails to abort. Let VM die immediately. if (sig == SIGINT && is_error_reported()) { os::die(); } os::signal_notify(sig); } void* os::user_handler() { return CAST_FROM_FN_PTR(void*, UserHandler); } extern "C" { typedef void (*sa_handler_t)(int); typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); } void* os::signal(int signal_number, void* handler) { struct sigaction sigAct, oldSigAct; sigfillset(&(sigAct.sa_mask)); sigAct.sa_flags = SA_RESTART|SA_SIGINFO; sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler); if (sigaction(signal_number, &sigAct, &oldSigAct)) { // -1 means registration failed return (void *)-1; } return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler); } void os::signal_raise(int signal_number) { ::raise(signal_number); } /* * The following code is moved from os.cpp for making this * code platform specific, which it is by its very nature. */ // Will be modified when max signal is changed to be dynamic int os::sigexitnum_pd() { return NSIG; } // a counter for each possible signal value static volatile jint pending_signals[NSIG+1] = { 0 }; // Bsd(POSIX) specific hand shaking semaphore. #ifdef __APPLE__ typedef semaphore_t os_semaphore_t; #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value) #define SEM_WAIT(sem) semaphore_wait(sem) #define SEM_POST(sem) semaphore_signal(sem) #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem) #else typedef sem_t os_semaphore_t; #define SEM_INIT(sem, value) sem_init(&sem, 0, value) #define SEM_WAIT(sem) sem_wait(&sem) #define SEM_POST(sem) sem_post(&sem) #define SEM_DESTROY(sem) sem_destroy(&sem) #endif class Semaphore : public StackObj { public: Semaphore(); ~Semaphore(); void signal(); void wait(); bool trywait(); bool timedwait(unsigned int sec, int nsec); private: jlong currenttime() const; os_semaphore_t _semaphore; }; Semaphore::Semaphore() : _semaphore(0) { SEM_INIT(_semaphore, 0); } Semaphore::~Semaphore() { SEM_DESTROY(_semaphore); } void Semaphore::signal() { SEM_POST(_semaphore); } void Semaphore::wait() { SEM_WAIT(_semaphore); } jlong Semaphore::currenttime() const { struct timeval tv; gettimeofday(&tv, NULL); return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000); } #ifdef __APPLE__ bool Semaphore::trywait() { return timedwait(0, 0); } bool Semaphore::timedwait(unsigned int sec, int nsec) { kern_return_t kr = KERN_ABORTED; mach_timespec_t waitspec; waitspec.tv_sec = sec; waitspec.tv_nsec = nsec; jlong starttime = currenttime(); kr = semaphore_timedwait(_semaphore, waitspec); while (kr == KERN_ABORTED) { jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec; jlong current = currenttime(); jlong passedtime = current - starttime; if (passedtime >= totalwait) { waitspec.tv_sec = 0; waitspec.tv_nsec = 0; } else { jlong waittime = totalwait - (current - starttime); waitspec.tv_sec = waittime / NANOSECS_PER_SEC; waitspec.tv_nsec = waittime % NANOSECS_PER_SEC; } kr = semaphore_timedwait(_semaphore, waitspec); } return kr == KERN_SUCCESS; } #else bool Semaphore::trywait() { return sem_trywait(&_semaphore) == 0; } bool Semaphore::timedwait(unsigned int sec, int nsec) { struct timespec ts; unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec); while (1) { int result = sem_timedwait(&_semaphore, &ts); if (result == 0) { return true; } else if (errno == EINTR) { continue; } else if (errno == ETIMEDOUT) { return false; } else { return false; } } } #endif // __APPLE__ static os_semaphore_t sig_sem; static Semaphore sr_semaphore; void os::signal_init_pd() { // Initialize signal structures ::memset((void*)pending_signals, 0, sizeof(pending_signals)); // Initialize signal semaphore ::SEM_INIT(sig_sem, 0); } void os::signal_notify(int sig) { Atomic::inc(&pending_signals[sig]); ::SEM_POST(sig_sem); } static int check_pending_signals(bool wait) { Atomic::store(0, &sigint_count); for (;;) { for (int i = 0; i < NSIG + 1; i++) { jint n = pending_signals[i]; if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) { return i; } } if (!wait) { return -1; } JavaThread *thread = JavaThread::current(); ThreadBlockInVM tbivm(thread); bool threadIsSuspended; do { thread->set_suspend_equivalent(); // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() ::SEM_WAIT(sig_sem); // were we externally suspended while we were waiting? threadIsSuspended = thread->handle_special_suspend_equivalent_condition(); if (threadIsSuspended) { // // The semaphore has been incremented, but while we were waiting // another thread suspended us. We don't want to continue running // while suspended because that would surprise the thread that // suspended us. // ::SEM_POST(sig_sem); thread->java_suspend_self(); } } while (threadIsSuspended); } } int os::signal_lookup() { return check_pending_signals(false); } int os::signal_wait() { return check_pending_signals(true); } //////////////////////////////////////////////////////////////////////////////// // Virtual Memory int os::vm_page_size() { // Seems redundant as all get out assert(os::Bsd::page_size() != -1, "must call os::init"); return os::Bsd::page_size(); } // Solaris allocates memory by pages. int os::vm_allocation_granularity() { assert(os::Bsd::page_size() != -1, "must call os::init"); return os::Bsd::page_size(); } // Rationale behind this function: // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get // samples for JITted code. Here we create private executable mapping over the code cache // and then we can use standard (well, almost, as mapping can change) way to provide // info for the reporting script by storing timestamp and location of symbol void bsd_wrap_code(char* base, size_t size) { static volatile jint cnt = 0; if (!UseOprofile) { return; } char buf[PATH_MAX + 1]; int num = Atomic::add(1, &cnt); snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d", os::get_temp_directory(), os::current_process_id(), num); unlink(buf); int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU); if (fd != -1) { off_t rv = ::lseek(fd, size-2, SEEK_SET); if (rv != (off_t)-1) { if (::write(fd, "", 1) == 1) { mmap(base, size, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0); } } ::close(fd); unlink(buf); } } static void warn_fail_commit_memory(char* addr, size_t size, bool exec, int err) { warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT ", %d) failed; error='%s' (errno=%d)", addr, size, exec, strerror(err), err); } // NOTE: Bsd kernel does not really reserve the pages for us. // All it does is to check if there are enough free pages // left at the time of mmap(). This could be a potential // problem. bool os::pd_commit_memory(char* addr, size_t size, bool exec) { int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE; #ifdef __OpenBSD__ // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD if (::mprotect(addr, size, prot) == 0) { return true; } #else uintptr_t res = (uintptr_t) ::mmap(addr, size, prot, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0); if (res != (uintptr_t) MAP_FAILED) { return true; } #endif // Warn about any commit errors we see in non-product builds just // in case mmap() doesn't work as described on the man page. NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);) return false; } bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint, bool exec) { // alignment_hint is ignored on this OS return pd_commit_memory(addr, size, exec); } void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec, const char* mesg) { assert(mesg != NULL, "mesg must be specified"); if (!pd_commit_memory(addr, size, exec)) { // add extra info in product mode for vm_exit_out_of_memory(): PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);) vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg); } } void os::pd_commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint, bool exec, const char* mesg) { // alignment_hint is ignored on this OS pd_commit_memory_or_exit(addr, size, exec, mesg); } void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { } void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { ::madvise(addr, bytes, MADV_DONTNEED); } void os::numa_make_global(char *addr, size_t bytes) { } void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { } bool os::numa_topology_changed() { return false; } size_t os::numa_get_groups_num() { return 1; } int os::numa_get_group_id() { return 0; } size_t os::numa_get_leaf_groups(int *ids, size_t size) { if (size > 0) { ids[0] = 0; return 1; } return 0; } bool os::get_page_info(char *start, page_info* info) { return false; } char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) { return end; } bool os::pd_uncommit_memory(char* addr, size_t size) { #ifdef __OpenBSD__ // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD return ::mprotect(addr, size, PROT_NONE) == 0; #else uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0); return res != (uintptr_t) MAP_FAILED; #endif } bool os::pd_create_stack_guard_pages(char* addr, size_t size) { return os::commit_memory(addr, size, !ExecMem); } // If this is a growable mapping, remove the guard pages entirely by // munmap()ping them. If not, just call uncommit_memory(). bool os::remove_stack_guard_pages(char* addr, size_t size) { return os::uncommit_memory(addr, size); } static address _highest_vm_reserved_address = NULL; // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory // at 'requested_addr'. If there are existing memory mappings at the same // location, however, they will be overwritten. If 'fixed' is false, // 'requested_addr' is only treated as a hint, the return value may or // may not start from the requested address. Unlike Bsd mmap(), this // function returns NULL to indicate failure. static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) { char * addr; int flags; flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS; if (fixed) { assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address"); flags |= MAP_FIXED; } // Map reserved/uncommitted pages PROT_NONE so we fail early if we // touch an uncommitted page. Otherwise, the read/write might // succeed if we have enough swap space to back the physical page. addr = (char*)::mmap(requested_addr, bytes, PROT_NONE, flags, -1, 0); if (addr != MAP_FAILED) { // anon_mmap() should only get called during VM initialization, // don't need lock (actually we can skip locking even it can be called // from multiple threads, because _highest_vm_reserved_address is just a // hint about the upper limit of non-stack memory regions.) if ((address)addr + bytes > _highest_vm_reserved_address) { _highest_vm_reserved_address = (address)addr + bytes; } } return addr == MAP_FAILED ? NULL : addr; } // Don't update _highest_vm_reserved_address, because there might be memory // regions above addr + size. If so, releasing a memory region only creates // a hole in the address space, it doesn't help prevent heap-stack collision. // static int anon_munmap(char * addr, size_t size) { return ::munmap(addr, size) == 0; } char* os::pd_reserve_memory(size_t bytes, char* requested_addr, size_t alignment_hint) { return anon_mmap(requested_addr, bytes, (requested_addr != NULL)); } bool os::pd_release_memory(char* addr, size_t size) { return anon_munmap(addr, size); } static bool bsd_mprotect(char* addr, size_t size, int prot) { // Bsd wants the mprotect address argument to be page aligned. char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size()); // According to SUSv3, mprotect() should only be used with mappings // established by mmap(), and mmap() always maps whole pages. Unaligned // 'addr' likely indicates problem in the VM (e.g. trying to change // protection of malloc'ed or statically allocated memory). Check the // caller if you hit this assert. assert(addr == bottom, "sanity check"); size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size()); return ::mprotect(bottom, size, prot) == 0; } // Set protections specified bool os::protect_memory(char* addr, size_t bytes, ProtType prot, bool is_committed) { unsigned int p = 0; switch (prot) { case MEM_PROT_NONE: p = PROT_NONE; break; case MEM_PROT_READ: p = PROT_READ; break; case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break; case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break; default: ShouldNotReachHere(); } // is_committed is unused. return bsd_mprotect(addr, bytes, p); } bool os::guard_memory(char* addr, size_t size) { return bsd_mprotect(addr, size, PROT_NONE); } bool os::unguard_memory(char* addr, size_t size) { return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE); } bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) { return false; } // Large page support static size_t _large_page_size = 0; void os::large_page_init() { } char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) { fatal("This code is not used or maintained."); // "exec" is passed in but not used. Creating the shared image for // the code cache doesn't have an SHM_X executable permission to check. assert(UseLargePages && UseSHM, "only for SHM large pages"); key_t key = IPC_PRIVATE; char *addr; bool warn_on_failure = UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) || !FLAG_IS_DEFAULT(LargePageSizeInBytes) ); // Create a large shared memory region to attach to based on size. // Currently, size is the total size of the heap int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W); if (shmid == -1) { // Possible reasons for shmget failure: // 1. shmmax is too small for Java heap. // > check shmmax value: cat /proc/sys/kernel/shmmax // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax // 2. not enough large page memory. // > check available large pages: cat /proc/meminfo // > increase amount of large pages: // echo new_value > /proc/sys/vm/nr_hugepages // Note 1: different Bsd may use different name for this property, // e.g. on Redhat AS-3 it is "hugetlb_pool". // Note 2: it's possible there's enough physical memory available but // they are so fragmented after a long run that they can't // coalesce into large pages. Try to reserve large pages when // the system is still "fresh". if (warn_on_failure) { warning("Failed to reserve shared memory (errno = %d).", errno); } return NULL; } // attach to the region addr = (char*)shmat(shmid, req_addr, 0); int err = errno; // Remove shmid. If shmat() is successful, the actual shared memory segment // will be deleted when it's detached by shmdt() or when the process // terminates. If shmat() is not successful this will remove the shared // segment immediately. shmctl(shmid, IPC_RMID, NULL); if ((intptr_t)addr == -1) { if (warn_on_failure) { warning("Failed to attach shared memory (errno = %d).", err); } return NULL; } // The memory is committed MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC); return addr; } bool os::release_memory_special(char* base, size_t bytes) { if (MemTracker::tracking_level() > NMT_minimal) { Tracker tkr = MemTracker::get_virtual_memory_release_tracker(); // detaching the SHM segment will also delete it, see reserve_memory_special() int rslt = shmdt(base); if (rslt == 0) { tkr.record((address)base, bytes); return true; } else { return false; } } else { return shmdt(base) == 0; } } size_t os::large_page_size() { return _large_page_size; } // HugeTLBFS allows application to commit large page memory on demand; // with SysV SHM the entire memory region must be allocated as shared // memory. bool os::can_commit_large_page_memory() { return UseHugeTLBFS; } bool os::can_execute_large_page_memory() { return UseHugeTLBFS; } // Reserve memory at an arbitrary address, only if that area is // available (and not reserved for something else). char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) { const int max_tries = 10; char* base[max_tries]; size_t size[max_tries]; const size_t gap = 0x000000; // Assert only that the size is a multiple of the page size, since // that's all that mmap requires, and since that's all we really know // about at this low abstraction level. If we need higher alignment, // we can either pass an alignment to this method or verify alignment // in one of the methods further up the call chain. See bug 5044738. assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block"); // Repeatedly allocate blocks until the block is allocated at the // right spot. Give up after max_tries. Note that reserve_memory() will // automatically update _highest_vm_reserved_address if the call is // successful. The variable tracks the highest memory address every reserved // by JVM. It is used to detect heap-stack collision if running with // fixed-stack BsdThreads. Because here we may attempt to reserve more // space than needed, it could confuse the collision detecting code. To // solve the problem, save current _highest_vm_reserved_address and // calculate the correct value before return. address old_highest = _highest_vm_reserved_address; // Bsd mmap allows caller to pass an address as hint; give it a try first, // if kernel honors the hint then we can return immediately. char * addr = anon_mmap(requested_addr, bytes, false); if (addr == requested_addr) { return requested_addr; } if (addr != NULL) { // mmap() is successful but it fails to reserve at the requested address anon_munmap(addr, bytes); } int i; for (i = 0; i < max_tries; ++i) { base[i] = reserve_memory(bytes); if (base[i] != NULL) { // Is this the block we wanted? if (base[i] == requested_addr) { size[i] = bytes; break; } // Does this overlap the block we wanted? Give back the overlapped // parts and try again. size_t top_overlap = requested_addr + (bytes + gap) - base[i]; if (top_overlap >= 0 && top_overlap < bytes) { unmap_memory(base[i], top_overlap); base[i] += top_overlap; size[i] = bytes - top_overlap; } else { size_t bottom_overlap = base[i] + bytes - requested_addr; if (bottom_overlap >= 0 && bottom_overlap < bytes) { unmap_memory(requested_addr, bottom_overlap); size[i] = bytes - bottom_overlap; } else { size[i] = bytes; } } } } // Give back the unused reserved pieces. for (int j = 0; j < i; ++j) { if (base[j] != NULL) { unmap_memory(base[j], size[j]); } } if (i < max_tries) { _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes); return requested_addr; } else { _highest_vm_reserved_address = old_highest; return NULL; } } size_t os::read(int fd, void *buf, unsigned int nBytes) { RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes)); } void os::naked_short_sleep(jlong ms) { struct timespec req; assert(ms < 1000, "Un-interruptable sleep, short time use only"); req.tv_sec = 0; if (ms > 0) { req.tv_nsec = (ms % 1000) * 1000000; } else { req.tv_nsec = 1; } nanosleep(&req, NULL); return; } // Sleep forever; naked call to OS-specific sleep; use with CAUTION void os::infinite_sleep() { while (true) { // sleep forever ... ::sleep(100); // ... 100 seconds at a time } } // Used to convert frequent JVM_Yield() to nops bool os::dont_yield() { return DontYieldALot; } void os::naked_yield() { sched_yield(); } //////////////////////////////////////////////////////////////////////////////// // thread priority support // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER // only supports dynamic priority, static priority must be zero. For real-time // applications, Bsd supports SCHED_RR which allows static priority (1-99). // However, for large multi-threaded applications, SCHED_RR is not only slower // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out // of 5 runs - Sep 2005). // // The following code actually changes the niceness of kernel-thread/LWP. It // has an assumption that setpriority() only modifies one kernel-thread/LWP, // not the entire user process, and user level threads are 1:1 mapped to kernel // threads. It has always been the case, but could change in the future. For // this reason, the code should not be used as default (ThreadPriorityPolicy=0). // It is only used when ThreadPriorityPolicy=1 and requires root privilege. #if !defined(__APPLE__) int os::java_to_os_priority[CriticalPriority + 1] = { 19, // 0 Entry should never be used 0, // 1 MinPriority 3, // 2 6, // 3 10, // 4 15, // 5 NormPriority 18, // 6 21, // 7 25, // 8 28, // 9 NearMaxPriority 31, // 10 MaxPriority 31 // 11 CriticalPriority }; #else /* Using Mach high-level priority assignments */ int os::java_to_os_priority[CriticalPriority + 1] = { 0, // 0 Entry should never be used (MINPRI_USER) 27, // 1 MinPriority 28, // 2 29, // 3 30, // 4 31, // 5 NormPriority (BASEPRI_DEFAULT) 32, // 6 33, // 7 34, // 8 35, // 9 NearMaxPriority 36, // 10 MaxPriority 36 // 11 CriticalPriority }; #endif static int prio_init() { if (ThreadPriorityPolicy == 1) { // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1 // if effective uid is not root. Perhaps, a more elegant way of doing // this is to test CAP_SYS_NICE capability, but that will require libcap.so if (geteuid() != 0) { if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) { warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd"); } ThreadPriorityPolicy = 0; } } if (UseCriticalJavaThreadPriority) { os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority]; } return 0; } OSReturn os::set_native_priority(Thread* thread, int newpri) { if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK; #ifdef __OpenBSD__ // OpenBSD pthread_setprio starves low priority threads return OS_OK; #elif defined(__FreeBSD__) int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri); #elif defined(__APPLE__) || defined(__NetBSD__) struct sched_param sp; int policy; pthread_t self = pthread_self(); if (pthread_getschedparam(self, &policy, &sp) != 0) return OS_ERR; sp.sched_priority = newpri; if (pthread_setschedparam(self, policy, &sp) != 0) return OS_ERR; return OS_OK; #else int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri); return (ret == 0) ? OS_OK : OS_ERR; #endif } OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) { if (!UseThreadPriorities || ThreadPriorityPolicy == 0) { *priority_ptr = java_to_os_priority[NormPriority]; return OS_OK; } errno = 0; #if defined(__OpenBSD__) || defined(__FreeBSD__) *priority_ptr = pthread_getprio(thread->osthread()->pthread_id()); #elif defined(__APPLE__) || defined(__NetBSD__) int policy; struct sched_param sp; pthread_getschedparam(pthread_self(), &policy, &sp); *priority_ptr = sp.sched_priority; #else *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id()); #endif return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR); } // Hint to the underlying OS that a task switch would not be good. // Void return because it's a hint and can fail. void os::hint_no_preempt() {} //////////////////////////////////////////////////////////////////////////////// // suspend/resume support // the low-level signal-based suspend/resume support is a remnant from the // old VM-suspension that used to be for java-suspension, safepoints etc, // within hotspot. Now there is a single use-case for this: // - calling get_thread_pc() on the VMThread by the flat-profiler task // that runs in the watcher thread. // The remaining code is greatly simplified from the more general suspension // code that used to be used. // // The protocol is quite simple: // - suspend: // - sends a signal to the target thread // - polls the suspend state of the osthread using a yield loop // - target thread signal handler (SR_handler) sets suspend state // and blocks in sigsuspend until continued // - resume: // - sets target osthread state to continue // - sends signal to end the sigsuspend loop in the SR_handler // // Note that the SR_lock plays no role in this suspend/resume protocol. // static void resume_clear_context(OSThread *osthread) { osthread->set_ucontext(NULL); osthread->set_siginfo(NULL); } static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) { osthread->set_ucontext(context); osthread->set_siginfo(siginfo); } // // Handler function invoked when a thread's execution is suspended or // resumed. We have to be careful that only async-safe functions are // called here (Note: most pthread functions are not async safe and // should be avoided.) // // Note: sigwait() is a more natural fit than sigsuspend() from an // interface point of view, but sigwait() prevents the signal hander // from being run. libpthread would get very confused by not having // its signal handlers run and prevents sigwait()'s use with the // mutex granting granting signal. // // Currently only ever called on the VMThread or JavaThread // static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) { // Save and restore errno to avoid confusing native code with EINTR // after sigsuspend. int old_errno = errno; Thread* thread = Thread::current(); OSThread* osthread = thread->osthread(); assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread"); os::SuspendResume::State current = osthread->sr.state(); if (current == os::SuspendResume::SR_SUSPEND_REQUEST) { suspend_save_context(osthread, siginfo, context); // attempt to switch the state, we assume we had a SUSPEND_REQUEST os::SuspendResume::State state = osthread->sr.suspended(); if (state == os::SuspendResume::SR_SUSPENDED) { sigset_t suspend_set; // signals for sigsuspend() // get current set of blocked signals and unblock resume signal pthread_sigmask(SIG_BLOCK, NULL, &suspend_set); sigdelset(&suspend_set, SR_signum); sr_semaphore.signal(); // wait here until we are resumed while (1) { sigsuspend(&suspend_set); os::SuspendResume::State result = osthread->sr.running(); if (result == os::SuspendResume::SR_RUNNING) { sr_semaphore.signal(); break; } else if (result != os::SuspendResume::SR_SUSPENDED) { ShouldNotReachHere(); } } } else if (state == os::SuspendResume::SR_RUNNING) { // request was cancelled, continue } else { ShouldNotReachHere(); } resume_clear_context(osthread); } else if (current == os::SuspendResume::SR_RUNNING) { // request was cancelled, continue } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) { // ignore } else { // ignore } errno = old_errno; } static int SR_initialize() { struct sigaction act; char *s; /* Get signal number to use for suspend/resume */ if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) { int sig = ::strtol(s, 0, 10); if (sig > 0 || sig < NSIG) { SR_signum = sig; } } assert(SR_signum > SIGSEGV && SR_signum > SIGBUS, "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769"); sigemptyset(&SR_sigset); sigaddset(&SR_sigset, SR_signum); /* Set up signal handler for suspend/resume */ act.sa_flags = SA_RESTART|SA_SIGINFO; act.sa_handler = (void (*)(int)) SR_handler; // SR_signum is blocked by default. // 4528190 - We also need to block pthread restart signal (32 on all // supported Bsd platforms). Note that BsdThreads need to block // this signal for all threads to work properly. So we don't have // to use hard-coded signal number when setting up the mask. pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask); if (sigaction(SR_signum, &act, 0) == -1) { return -1; } // Save signal flag os::Bsd::set_our_sigflags(SR_signum, act.sa_flags); return 0; } static int sr_notify(OSThread* osthread) { int status = pthread_kill(osthread->pthread_id(), SR_signum); assert_status(status == 0, status, "pthread_kill"); return status; } // "Randomly" selected value for how long we want to spin // before bailing out on suspending a thread, also how often // we send a signal to a thread we want to resume static const int RANDOMLY_LARGE_INTEGER = 1000000; static const int RANDOMLY_LARGE_INTEGER2 = 100; // returns true on success and false on error - really an error is fatal // but this seems the normal response to library errors static bool do_suspend(OSThread* osthread) { assert(osthread->sr.is_running(), "thread should be running"); assert(!sr_semaphore.trywait(), "semaphore has invalid state"); // mark as suspended and send signal if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) { // failed to switch, state wasn't running? ShouldNotReachHere(); return false; } if (sr_notify(osthread) != 0) { ShouldNotReachHere(); } // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED while (true) { if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { break; } else { // timeout os::SuspendResume::State cancelled = osthread->sr.cancel_suspend(); if (cancelled == os::SuspendResume::SR_RUNNING) { return false; } else if (cancelled == os::SuspendResume::SR_SUSPENDED) { // make sure that we consume the signal on the semaphore as well sr_semaphore.wait(); break; } else { ShouldNotReachHere(); return false; } } } guarantee(osthread->sr.is_suspended(), "Must be suspended"); return true; } static void do_resume(OSThread* osthread) { assert(osthread->sr.is_suspended(), "thread should be suspended"); assert(!sr_semaphore.trywait(), "invalid semaphore state"); if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) { // failed to switch to WAKEUP_REQUEST ShouldNotReachHere(); return; } while (true) { if (sr_notify(osthread) == 0) { if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) { if (osthread->sr.is_running()) { return; } } } else { ShouldNotReachHere(); } } guarantee(osthread->sr.is_running(), "Must be running!"); } /////////////////////////////////////////////////////////////////////////////////// // signal handling (except suspend/resume) // This routine may be used by user applications as a "hook" to catch signals. // The user-defined signal handler must pass unrecognized signals to this // routine, and if it returns true (non-zero), then the signal handler must // return immediately. If the flag "abort_if_unrecognized" is true, then this // routine will never retun false (zero), but instead will execute a VM panic // routine kill the process. // // If this routine returns false, it is OK to call it again. This allows // the user-defined signal handler to perform checks either before or after // the VM performs its own checks. Naturally, the user code would be making // a serious error if it tried to handle an exception (such as a null check // or breakpoint) that the VM was generating for its own correct operation. // // This routine may recognize any of the following kinds of signals: // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1. // It should be consulted by handlers for any of those signals. // // The caller of this routine must pass in the three arguments supplied // to the function referred to in the "sa_sigaction" (not the "sa_handler") // field of the structure passed to sigaction(). This routine assumes that // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART. // // Note that the VM will print warnings if it detects conflicting signal // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers". // extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized); void signalHandler(int sig, siginfo_t* info, void* uc) { assert(info != NULL && uc != NULL, "it must be old kernel"); int orig_errno = errno; // Preserve errno value over signal handler. JVM_handle_bsd_signal(sig, info, uc, true); errno = orig_errno; } // This boolean allows users to forward their own non-matching signals // to JVM_handle_bsd_signal, harmlessly. bool os::Bsd::signal_handlers_are_installed = false; // For signal-chaining struct sigaction os::Bsd::sigact[MAXSIGNUM]; unsigned int os::Bsd::sigs = 0; bool os::Bsd::libjsig_is_loaded = false; typedef struct sigaction *(*get_signal_t)(int); get_signal_t os::Bsd::get_signal_action = NULL; struct sigaction* os::Bsd::get_chained_signal_action(int sig) { struct sigaction *actp = NULL; if (libjsig_is_loaded) { // Retrieve the old signal handler from libjsig actp = (*get_signal_action)(sig); } if (actp == NULL) { // Retrieve the preinstalled signal handler from jvm actp = get_preinstalled_handler(sig); } return actp; } static bool call_chained_handler(struct sigaction *actp, int sig, siginfo_t *siginfo, void *context) { // Call the old signal handler if (actp->sa_handler == SIG_DFL) { // It's more reasonable to let jvm treat it as an unexpected exception // instead of taking the default action. return false; } else if (actp->sa_handler != SIG_IGN) { if ((actp->sa_flags & SA_NODEFER) == 0) { // automaticlly block the signal sigaddset(&(actp->sa_mask), sig); } sa_handler_t hand; sa_sigaction_t sa; bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0; // retrieve the chained handler if (siginfo_flag_set) { sa = actp->sa_sigaction; } else { hand = actp->sa_handler; } if ((actp->sa_flags & SA_RESETHAND) != 0) { actp->sa_handler = SIG_DFL; } // try to honor the signal mask sigset_t oset; pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset); // call into the chained handler if (siginfo_flag_set) { (*sa)(sig, siginfo, context); } else { (*hand)(sig); } // restore the signal mask pthread_sigmask(SIG_SETMASK, &oset, 0); } // Tell jvm's signal handler the signal is taken care of. return true; } bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) { bool chained = false; // signal-chaining if (UseSignalChaining) { struct sigaction *actp = get_chained_signal_action(sig); if (actp != NULL) { chained = call_chained_handler(actp, sig, siginfo, context); } } return chained; } struct sigaction* os::Bsd::get_preinstalled_handler(int sig) { if ((((unsigned int)1 << sig) & sigs) != 0) { return &sigact[sig]; } return NULL; } void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) { assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); sigact[sig] = oldAct; sigs |= (unsigned int)1 << sig; } // for diagnostic int os::Bsd::sigflags[MAXSIGNUM]; int os::Bsd::get_our_sigflags(int sig) { assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); return sigflags[sig]; } void os::Bsd::set_our_sigflags(int sig, int flags) { assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); sigflags[sig] = flags; } void os::Bsd::set_signal_handler(int sig, bool set_installed) { // Check for overwrite. struct sigaction oldAct; sigaction(sig, (struct sigaction*)NULL, &oldAct); void* oldhand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) && oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) && oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) { if (AllowUserSignalHandlers || !set_installed) { // Do not overwrite; user takes responsibility to forward to us. return; } else if (UseSignalChaining) { // save the old handler in jvm save_preinstalled_handler(sig, oldAct); // libjsig also interposes the sigaction() call below and saves the // old sigaction on it own. } else { fatal(err_msg("Encountered unexpected pre-existing sigaction handler " "%#lx for signal %d.", (long)oldhand, sig)); } } struct sigaction sigAct; sigfillset(&(sigAct.sa_mask)); sigAct.sa_handler = SIG_DFL; if (!set_installed) { sigAct.sa_flags = SA_SIGINFO|SA_RESTART; } else { sigAct.sa_sigaction = signalHandler; sigAct.sa_flags = SA_SIGINFO|SA_RESTART; } #ifdef __APPLE__ // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages" // if the signal handler declares it will handle it on alternate stack. // Notice we only declare we will handle it on alt stack, but we are not // actually going to use real alt stack - this is just a workaround. // Please see ux_exception.c, method catch_mach_exception_raise for details // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c if (sig == SIGSEGV) { sigAct.sa_flags |= SA_ONSTACK; } #endif // Save flags, which are set by ours assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range"); sigflags[sig] = sigAct.sa_flags; int ret = sigaction(sig, &sigAct, &oldAct); assert(ret == 0, "check"); void* oldhand2 = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction) : CAST_FROM_FN_PTR(void*, oldAct.sa_handler); assert(oldhand2 == oldhand, "no concurrent signal handler installation"); } // install signal handlers for signals that HotSpot needs to // handle in order to support Java-level exception handling. void os::Bsd::install_signal_handlers() { if (!signal_handlers_are_installed) { signal_handlers_are_installed = true; // signal-chaining typedef void (*signal_setting_t)(); signal_setting_t begin_signal_setting = NULL; signal_setting_t end_signal_setting = NULL; begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t, dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting")); if (begin_signal_setting != NULL) { end_signal_setting = CAST_TO_FN_PTR(signal_setting_t, dlsym(RTLD_DEFAULT, "JVM_end_signal_setting")); get_signal_action = CAST_TO_FN_PTR(get_signal_t, dlsym(RTLD_DEFAULT, "JVM_get_signal_action")); libjsig_is_loaded = true; assert(UseSignalChaining, "should enable signal-chaining"); } if (libjsig_is_loaded) { // Tell libjsig jvm is setting signal handlers (*begin_signal_setting)(); } set_signal_handler(SIGSEGV, true); set_signal_handler(SIGPIPE, true); set_signal_handler(SIGBUS, true); set_signal_handler(SIGILL, true); set_signal_handler(SIGFPE, true); set_signal_handler(SIGXFSZ, true); #if defined(__APPLE__) // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including // signals caught and handled by the JVM. To work around this, we reset the mach task // signal handler that's placed on our process by CrashReporter. This disables // CrashReporter-based reporting. // // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes // on caught fatal signals. // // Additionally, gdb installs both standard BSD signal handlers, and mach exception // handlers. By replacing the existing task exception handler, we disable gdb's mach // exception handling, while leaving the standard BSD signal handlers functional. kern_return_t kr; kr = task_set_exception_ports(mach_task_self(), EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, MACH_PORT_NULL, EXCEPTION_STATE_IDENTITY, MACHINE_THREAD_STATE); assert(kr == KERN_SUCCESS, "could not set mach task signal handler"); #endif if (libjsig_is_loaded) { // Tell libjsig jvm finishes setting signal handlers (*end_signal_setting)(); } // We don't activate signal checker if libjsig is in place, we trust ourselves // and if UserSignalHandler is installed all bets are off if (CheckJNICalls) { if (libjsig_is_loaded) { if (PrintJNIResolving) { tty->print_cr("Info: libjsig is activated, all active signal checking is disabled"); } check_signals = false; } if (AllowUserSignalHandlers) { if (PrintJNIResolving) { tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled"); } check_signals = false; } } } } ///// // glibc on Bsd platform uses non-documented flag // to indicate, that some special sort of signal // trampoline is used. // We will never set this flag, and we should // ignore this flag in our diagnostic #ifdef SIGNIFICANT_SIGNAL_MASK #undef SIGNIFICANT_SIGNAL_MASK #endif #define SIGNIFICANT_SIGNAL_MASK (~0x04000000) static const char* get_signal_handler_name(address handler, char* buf, int buflen) { int offset; bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset); if (found) { // skip directory names const char *p1, *p2; p1 = buf; size_t len = strlen(os::file_separator()); while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; jio_snprintf(buf, buflen, "%s+0x%x", p1, offset); } else { jio_snprintf(buf, buflen, PTR_FORMAT, handler); } return buf; } static void print_signal_handler(outputStream* st, int sig, char* buf, size_t buflen) { struct sigaction sa; sigaction(sig, NULL, &sa); // See comment for SIGNIFICANT_SIGNAL_MASK define sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK; st->print("%s: ", os::exception_name(sig, buf, buflen)); address handler = (sa.sa_flags & SA_SIGINFO) ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) : CAST_FROM_FN_PTR(address, sa.sa_handler); if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) { st->print("SIG_DFL"); } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) { st->print("SIG_IGN"); } else { st->print("[%s]", get_signal_handler_name(handler, buf, buflen)); } st->print(", sa_mask[0]="); os::Posix::print_signal_set_short(st, &sa.sa_mask); address rh = VMError::get_resetted_sighandler(sig); // May be, handler was resetted by VMError? if (rh != NULL) { handler = rh; sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK; } st->print(", sa_flags="); os::Posix::print_sa_flags(st, sa.sa_flags); // Check: is it our handler? if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) || handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) { // It is our signal handler // check for flags, reset system-used one! if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) { st->print( ", flags was changed from " PTR32_FORMAT ", consider using jsig library", os::Bsd::get_our_sigflags(sig)); } } st->cr(); } #define DO_SIGNAL_CHECK(sig) \ if (!sigismember(&check_signal_done, sig)) \ os::Bsd::check_signal_handler(sig) // This method is a periodic task to check for misbehaving JNI applications // under CheckJNI, we can add any periodic checks here void os::run_periodic_checks() { if (check_signals == false) return; // SEGV and BUS if overridden could potentially prevent // generation of hs*.log in the event of a crash, debugging // such a case can be very challenging, so we absolutely // check the following for a good measure: DO_SIGNAL_CHECK(SIGSEGV); DO_SIGNAL_CHECK(SIGILL); DO_SIGNAL_CHECK(SIGFPE); DO_SIGNAL_CHECK(SIGBUS); DO_SIGNAL_CHECK(SIGPIPE); DO_SIGNAL_CHECK(SIGXFSZ); // ReduceSignalUsage allows the user to override these handlers // see comments at the very top and jvm_solaris.h if (!ReduceSignalUsage) { DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL); DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL); DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL); DO_SIGNAL_CHECK(BREAK_SIGNAL); } DO_SIGNAL_CHECK(SR_signum); DO_SIGNAL_CHECK(INTERRUPT_SIGNAL); } typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *); static os_sigaction_t os_sigaction = NULL; void os::Bsd::check_signal_handler(int sig) { char buf[O_BUFLEN]; address jvmHandler = NULL; struct sigaction act; if (os_sigaction == NULL) { // only trust the default sigaction, in case it has been interposed os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction"); if (os_sigaction == NULL) return; } os_sigaction(sig, (struct sigaction*)NULL, &act); act.sa_flags &= SIGNIFICANT_SIGNAL_MASK; address thisHandler = (act.sa_flags & SA_SIGINFO) ? CAST_FROM_FN_PTR(address, act.sa_sigaction) : CAST_FROM_FN_PTR(address, act.sa_handler); switch (sig) { case SIGSEGV: case SIGBUS: case SIGFPE: case SIGPIPE: case SIGILL: case SIGXFSZ: jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler); break; case SHUTDOWN1_SIGNAL: case SHUTDOWN2_SIGNAL: case SHUTDOWN3_SIGNAL: case BREAK_SIGNAL: jvmHandler = (address)user_handler(); break; case INTERRUPT_SIGNAL: jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL); break; default: if (sig == SR_signum) { jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler); } else { return; } break; } if (thisHandler != jvmHandler) { tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN)); tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN)); tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN)); // No need to check this sig any longer sigaddset(&check_signal_done, sig); // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) { tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell", exception_name(sig, buf, O_BUFLEN)); } } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) { tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN)); tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig)); tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags); // No need to check this sig any longer sigaddset(&check_signal_done, sig); } // Dump all the signal if (sigismember(&check_signal_done, sig)) { print_signal_handlers(tty, buf, O_BUFLEN); } } extern void report_error(char* file_name, int line_no, char* title, char* format, ...); extern bool signal_name(int signo, char* buf, size_t len); const char* os::exception_name(int exception_code, char* buf, size_t size) { if (0 < exception_code && exception_code <= SIGRTMAX) { // signal if (!signal_name(exception_code, buf, size)) { jio_snprintf(buf, size, "SIG%d", exception_code); } return buf; } else { return NULL; } } // this is called _before_ the most of global arguments have been parsed void os::init(void) { char dummy; /* used to get a guess on initial stack address */ // first_hrtime = gethrtime(); // With BsdThreads the JavaMain thread pid (primordial thread) // is different than the pid of the java launcher thread. // So, on Bsd, the launcher thread pid is passed to the VM // via the sun.java.launcher.pid property. // Use this property instead of getpid() if it was correctly passed. // See bug 6351349. pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid(); _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid(); clock_tics_per_sec = CLK_TCK; init_random(1234567); ThreadCritical::initialize(); Bsd::set_page_size(getpagesize()); if (Bsd::page_size() == -1) { fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno))); } init_page_sizes((size_t) Bsd::page_size()); Bsd::initialize_system_info(); // main_thread points to the aboriginal thread Bsd::_main_thread = pthread_self(); Bsd::clock_init(); initial_time_count = javaTimeNanos(); #ifdef __APPLE__ // XXXDARWIN // Work around the unaligned VM callbacks in hotspot's // sharedRuntime. The callbacks don't use SSE2 instructions, and work on // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces // alignment when doing symbol lookup. To work around this, we force early // binding of all symbols now, thus binding when alignment is known-good. _dyld_bind_fully_image_containing_address((const void *) &os::init); #endif } // To install functions for atexit system call extern "C" { static void perfMemory_exit_helper() { perfMemory_exit(); } } // this is called _after_ the global arguments have been parsed jint os::init_2(void) { // Allocate a single page and mark it as readable for safepoint polling address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page"); os::set_polling_page(polling_page); #ifndef PRODUCT if (Verbose && PrintMiscellaneous) tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page); #endif if (!UseMembar) { address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page"); os::set_memory_serialize_page(mem_serialize_page); #ifndef PRODUCT if (Verbose && PrintMiscellaneous) tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page); #endif } // initialize suspend/resume support - must do this before signal_sets_init() if (SR_initialize() != 0) { perror("SR_initialize failed"); return JNI_ERR; } Bsd::signal_sets_init(); Bsd::install_signal_handlers(); // Check minimum allowable stack size for thread creation and to initialize // the java system classes, including StackOverflowError - depends on page // size. Add a page for compiler2 recursion in main thread. // Add in 2*BytesPerWord times page size to account for VM stack during // class initialization depending on 32 or 64 bit VM. os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed, (size_t)(StackYellowPages+StackRedPages+StackShadowPages+ 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size()); size_t threadStackSizeInBytes = ThreadStackSize * K; if (threadStackSizeInBytes != 0 && threadStackSizeInBytes < os::Bsd::min_stack_allowed) { tty->print_cr("\nThe stack size specified is too small, " "Specify at least %dk", os::Bsd::min_stack_allowed/ K); return JNI_ERR; } // Make the stack size a multiple of the page size so that // the yellow/red zones can be guarded. JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes, vm_page_size())); if (MaxFDLimit) { // set the number of file descriptors to max. print out error // if getrlimit/setrlimit fails but continue regardless. struct rlimit nbr_files; int status = getrlimit(RLIMIT_NOFILE, &nbr_files); if (status != 0) { if (PrintMiscellaneous && (Verbose || WizardMode)) perror("os::init_2 getrlimit failed"); } else { nbr_files.rlim_cur = nbr_files.rlim_max; #ifdef __APPLE__ // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must // be used instead nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur); #endif status = setrlimit(RLIMIT_NOFILE, &nbr_files); if (status != 0) { if (PrintMiscellaneous && (Verbose || WizardMode)) perror("os::init_2 setrlimit failed"); } } } // at-exit methods are called in the reverse order of their registration. // atexit functions are called on return from main or as a result of a // call to exit(3C). There can be only 32 of these functions registered // and atexit() does not set errno. if (PerfAllowAtExitRegistration) { // only register atexit functions if PerfAllowAtExitRegistration is set. // atexit functions can be delayed until process exit time, which // can be problematic for embedded VM situations. Embedded VMs should // call DestroyJavaVM() to assure that VM resources are released. // note: perfMemory_exit_helper atexit function may be removed in // the future if the appropriate cleanup code can be added to the // VM_Exit VMOperation's doit method. if (atexit(perfMemory_exit_helper) != 0) { warning("os::init2 atexit(perfMemory_exit_helper) failed"); } } // initialize thread priority policy prio_init(); #ifdef __APPLE__ // dynamically link to objective c gc registration void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY); if (handleLibObjc != NULL) { objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER); } #endif return JNI_OK; } // this is called at the end of vm_initialization void os::init_3(void) { } // Mark the polling page as unreadable void os::make_polling_page_unreadable(void) { if (!guard_memory((char*)_polling_page, Bsd::page_size())) fatal("Could not disable polling page"); }; // Mark the polling page as readable void os::make_polling_page_readable(void) { if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) { fatal("Could not enable polling page"); } }; int os::active_processor_count() { return _processor_count; } void os::set_native_thread_name(const char *name) { #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5 // This is only supported in Snow Leopard and beyond if (name != NULL) { // Add a "Java: " prefix to the name char buf[MAXTHREADNAMESIZE]; snprintf(buf, sizeof(buf), "Java: %s", name); pthread_setname_np(buf); } #endif } bool os::distribute_processes(uint length, uint* distribution) { // Not yet implemented. return false; } bool os::bind_to_processor(uint processor_id) { // Not yet implemented. return false; } void os::SuspendedThreadTask::internal_do_task() { if (do_suspend(_thread->osthread())) { SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext()); do_task(context); do_resume(_thread->osthread()); } } /// class PcFetcher : public os::SuspendedThreadTask { public: PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {} ExtendedPC result(); protected: void do_task(const os::SuspendedThreadTaskContext& context); private: ExtendedPC _epc; }; ExtendedPC PcFetcher::result() { guarantee(is_done(), "task is not done yet."); return _epc; } void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) { Thread* thread = context.thread(); OSThread* osthread = thread->osthread(); if (osthread->ucontext() != NULL) { _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext()); } else { // NULL context is unexpected, double-check this is the VMThread guarantee(thread->is_VM_thread(), "can only be called for VMThread"); } } // Suspends the target using the signal mechanism and then grabs the PC before // resuming the target. Used by the flat-profiler only ExtendedPC os::get_thread_pc(Thread* thread) { // Make sure that it is called by the watcher for the VMThread assert(Thread::current()->is_Watcher_thread(), "Must be watcher"); assert(thread->is_VM_thread(), "Can only be called for VMThread"); PcFetcher fetcher(thread); fetcher.run(); return fetcher.result(); } int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime) { return pthread_cond_timedwait(_cond, _mutex, _abstime); } //////////////////////////////////////////////////////////////////////////////// // debug support bool os::find(address addr, outputStream* st) { Dl_info dlinfo; memset(&dlinfo, 0, sizeof(dlinfo)); if (dladdr(addr, &dlinfo) != 0) { st->print(PTR_FORMAT ": ", addr); if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) { st->print("%s+%#x", dlinfo.dli_sname, addr - (intptr_t)dlinfo.dli_saddr); } else if (dlinfo.dli_fbase != NULL) { st->print("", addr - (intptr_t)dlinfo.dli_fbase); } else { st->print(""); } if (dlinfo.dli_fname != NULL) { st->print(" in %s", dlinfo.dli_fname); } if (dlinfo.dli_fbase != NULL) { st->print(" at " PTR_FORMAT, dlinfo.dli_fbase); } st->cr(); if (Verbose) { // decode some bytes around the PC address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size()); address end = clamp_address_in_page(addr+40, addr, os::vm_page_size()); address lowest = (address) dlinfo.dli_sname; if (!lowest) lowest = (address) dlinfo.dli_fbase; if (begin < lowest) begin = lowest; Dl_info dlinfo2; if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) end = (address) dlinfo2.dli_saddr; Disassembler::decode(begin, end, st); } return true; } return false; } //////////////////////////////////////////////////////////////////////////////// // misc // This does not do anything on Bsd. This is basically a hook for being // able to use structured exception handling (thread-local exception filters) // on, e.g., Win32. void os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread) { f(value, method, args, thread); } void os::print_statistics() { } int os::message_box(const char* title, const char* message) { int i; fdStream err(defaultStream::error_fd()); for (i = 0; i < 78; i++) err.print_raw("="); err.cr(); err.print_raw_cr(title); for (i = 0; i < 78; i++) err.print_raw("-"); err.cr(); err.print_raw_cr(message); for (i = 0; i < 78; i++) err.print_raw("="); err.cr(); char buf[16]; // Prevent process from exiting upon "read error" without consuming all CPU while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); } return buf[0] == 'y' || buf[0] == 'Y'; } int os::stat(const char *path, struct stat *sbuf) { char pathbuf[MAX_PATH]; if (strlen(path) > MAX_PATH - 1) { errno = ENAMETOOLONG; return -1; } os::native_path(strcpy(pathbuf, path)); return ::stat(pathbuf, sbuf); } bool os::check_heap(bool force) { return true; } ATTRIBUTE_PRINTF(3, 0) int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) { return ::vsnprintf(buf, count, format, args); } // Is a (classpath) directory empty? bool os::dir_is_empty(const char* path) { DIR *dir = NULL; struct dirent *ptr; dir = opendir(path); if (dir == NULL) return true; /* Scan the directory */ bool result = true; char buf[sizeof(struct dirent) + MAX_PATH]; while (result && (ptr = ::readdir(dir)) != NULL) { if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) { result = false; } } closedir(dir); return result; } // This code originates from JDK's sysOpen and open64_w // from src/solaris/hpi/src/system_md.c #ifndef O_DELETE #define O_DELETE 0x10000 #endif // Open a file. Unlink the file immediately after open returns // if the specified oflag has the O_DELETE flag set. // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c int os::open(const char *path, int oflag, int mode) { if (strlen(path) > MAX_PATH - 1) { errno = ENAMETOOLONG; return -1; } int fd; int o_delete = (oflag & O_DELETE); oflag = oflag & ~O_DELETE; fd = ::open(path, oflag, mode); if (fd == -1) return -1; //If the open succeeded, the file might still be a directory { struct stat buf; int ret = ::fstat(fd, &buf); int st_mode = buf.st_mode; if (ret != -1) { if ((st_mode & S_IFMT) == S_IFDIR) { errno = EISDIR; ::close(fd); return -1; } } else { ::close(fd); return -1; } } /* * All file descriptors that are opened in the JVM and not * specifically destined for a subprocess should have the * close-on-exec flag set. If we don't set it, then careless 3rd * party native code might fork and exec without closing all * appropriate file descriptors (e.g. as we do in closeDescriptors in * UNIXProcess.c), and this in turn might: * * - cause end-of-file to fail to be detected on some file * descriptors, resulting in mysterious hangs, or * * - might cause an fopen in the subprocess to fail on a system * suffering from bug 1085341. * * (Yes, the default setting of the close-on-exec flag is a Unix * design flaw) * * See: * 1085341: 32-bit stdio routines should support file descriptors >255 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9 */ #ifdef FD_CLOEXEC { int flags = ::fcntl(fd, F_GETFD); if (flags != -1) ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC); } #endif if (o_delete != 0) { ::unlink(path); } return fd; } // create binary file, rewriting existing file if required int os::create_binary_file(const char* path, bool rewrite_existing) { int oflags = O_WRONLY | O_CREAT; if (!rewrite_existing) { oflags |= O_EXCL; } return ::open(path, oflags, S_IREAD | S_IWRITE); } // return current position of file pointer jlong os::current_file_offset(int fd) { return (jlong)::lseek(fd, (off_t)0, SEEK_CUR); } // move file pointer to the specified offset jlong os::seek_to_file_offset(int fd, jlong offset) { return (jlong)::lseek(fd, (off_t)offset, SEEK_SET); } // This code originates from JDK's sysAvailable // from src/solaris/hpi/src/native_threads/src/sys_api_td.c int os::available(int fd, jlong *bytes) { jlong cur, end; int mode; struct stat buf; if (::fstat(fd, &buf) >= 0) { mode = buf.st_mode; if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { /* * XXX: is the following call interruptible? If so, this might * need to go through the INTERRUPT_IO() wrapper as for other * blocking, interruptible calls in this file. */ int n; if (::ioctl(fd, FIONREAD, &n) >= 0) { *bytes = n; return 1; } } } if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) { return 0; } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) { return 0; } else if (::lseek(fd, cur, SEEK_SET) == -1) { return 0; } *bytes = end - cur; return 1; } int os::socket_available(int fd, jint *pbytes) { if (fd < 0) return OS_OK; int ret; RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret); //%% note ioctl can return 0 when successful, JVM_SocketAvailable // is expected to return 0 on failure and 1 on success to the jdk. return (ret == OS_ERR) ? 0 : 1; } // Map a block of memory. char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset, char *addr, size_t bytes, bool read_only, bool allow_exec) { int prot; int flags; if (read_only) { prot = PROT_READ; flags = MAP_SHARED; } else { prot = PROT_READ | PROT_WRITE; flags = MAP_PRIVATE; } if (allow_exec) { prot |= PROT_EXEC; } if (addr != NULL) { flags |= MAP_FIXED; } char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags, fd, file_offset); if (mapped_address == MAP_FAILED) { return NULL; } return mapped_address; } // Remap a block of memory. char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset, char *addr, size_t bytes, bool read_only, bool allow_exec) { // same as map_memory() on this OS return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec); } // Unmap a block of memory. bool os::pd_unmap_memory(char* addr, size_t bytes) { return munmap(addr, bytes) == 0; } // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool) // are used by JVM M&M and JVMTI to get user+sys or user CPU time // of a thread. // // current_thread_cpu_time() and thread_cpu_time(Thread*) returns // the fast estimate available on the platform. jlong os::current_thread_cpu_time() { #ifdef __APPLE__ return os::thread_cpu_time(Thread::current(), true /* user + sys */); #else Unimplemented(); return 0; #endif } jlong os::thread_cpu_time(Thread* thread) { #ifdef __APPLE__ return os::thread_cpu_time(thread, true /* user + sys */); #else Unimplemented(); return 0; #endif } jlong os::current_thread_cpu_time(bool user_sys_cpu_time) { #ifdef __APPLE__ return os::thread_cpu_time(Thread::current(), user_sys_cpu_time); #else Unimplemented(); return 0; #endif } jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) { #ifdef __APPLE__ struct thread_basic_info tinfo; mach_msg_type_number_t tcount = THREAD_INFO_MAX; kern_return_t kr; thread_t mach_thread; mach_thread = thread->osthread()->thread_id(); kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount); if (kr != KERN_SUCCESS) return -1; if (user_sys_cpu_time) { jlong nanos; nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000; nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000; return nanos; } else { return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000); } #else Unimplemented(); return 0; #endif } void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits info_ptr->may_skip_backward = false; // elapsed time not wall time info_ptr->may_skip_forward = false; // elapsed time not wall time info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned } void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) { info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits info_ptr->may_skip_backward = false; // elapsed time not wall time info_ptr->may_skip_forward = false; // elapsed time not wall time info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned } bool os::is_thread_cpu_time_supported() { #ifdef __APPLE__ return true; #else return false; #endif } // System loadavg support. Returns -1 if load average cannot be obtained. // Bsd doesn't yet have a (official) notion of processor sets, // so just return the system wide load average. int os::loadavg(double loadavg[], int nelem) { return ::getloadavg(loadavg, nelem); } void os::pause() { char filename[MAX_PATH]; if (PauseAtStartupFile && PauseAtStartupFile[0]) { jio_snprintf(filename, MAX_PATH, PauseAtStartupFile); } else { jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id()); } int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666); if (fd != -1) { struct stat buf; ::close(fd); while (::stat(filename, &buf) == 0) { (void)::poll(NULL, 0, 100); } } else { jio_fprintf(stderr, "Could not open pause file '%s', continuing immediately.\n", filename); } } // Refer to the comments in os_solaris.cpp park-unpark. // // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable. // For specifics regarding the bug see GLIBC BUGID 261237 : // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html. // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar // is used. (The simple C test-case provided in the GLIBC bug report manifests the // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos() // and monitorenter when we're using 1-0 locking. All those operations may result in // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version // of libpthread avoids the problem, but isn't practical. // // Possible remedies: // // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work. // This is palliative and probabilistic, however. If the thread is preempted // between the call to compute_abstime() and pthread_cond_timedwait(), more // than the minimum period may have passed, and the abstime may be stale (in the // past) resultin in a hang. Using this technique reduces the odds of a hang // but the JVM is still vulnerable, particularly on heavily loaded systems. // // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead // of the usual flag-condvar-mutex idiom. The write side of the pipe is set // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo) // reduces to poll()+read(). This works well, but consumes 2 FDs per extant // thread. // // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing // a timeout request to the chron thread and then blocking via pthread_cond_wait(). // This also works well. In fact it avoids kernel-level scalability impediments // on certain platforms that don't handle lots of active pthread_cond_timedwait() // timers in a graceful fashion. // // 4. When the abstime value is in the past it appears that control returns // correctly from pthread_cond_timedwait(), but the condvar is left corrupt. // Subsequent timedwait/wait calls may hang indefinitely. Given that, we // can avoid the problem by reinitializing the condvar -- by cond_destroy() // followed by cond_init() -- after all calls to pthread_cond_timedwait(). // It may be possible to avoid reinitialization by checking the return // value from pthread_cond_timedwait(). In addition to reinitializing the // condvar we must establish the invariant that cond_signal() is only called // within critical sections protected by the adjunct mutex. This prevents // cond_signal() from "seeing" a condvar that's in the midst of being // reinitialized or that is corrupt. Sadly, this invariant obviates the // desirable signal-after-unlock optimization that avoids futile context switching. // // I'm also concerned that some versions of NTPL might allocate an auxilliary // structure when a condvar is used or initialized. cond_destroy() would // release the helper structure. Our reinitialize-after-timedwait fix // put excessive stress on malloc/free and locks protecting the c-heap. // // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag. // It may be possible to refine (4) by checking the kernel and NTPL verisons // and only enabling the work-around for vulnerable environments. // utility to compute the abstime argument to timedwait: // millis is the relative timeout time // abstime will be the absolute timeout time // TODO: replace compute_abstime() with unpackTime() static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) { if (millis < 0) millis = 0; struct timeval now; int status = gettimeofday(&now, NULL); assert(status == 0, "gettimeofday"); jlong seconds = millis / 1000; millis %= 1000; if (seconds > 50000000) { // see man cond_timedwait(3T) seconds = 50000000; } abstime->tv_sec = now.tv_sec + seconds; long usec = now.tv_usec + millis * 1000; if (usec >= 1000000) { abstime->tv_sec += 1; usec -= 1000000; } abstime->tv_nsec = usec * 1000; return abstime; } void os::PlatformEvent::park() { // AKA "down()" // Invariant: Only the thread associated with the Event/PlatformEvent // may call park(). // TODO: assert that _Assoc != NULL or _Assoc == Self assert(_nParked == 0, "invariant"); int v; for (;;) { v = _Event; if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; } guarantee(v >= 0, "invariant"); if (v == 0) { // Do this the hard way by blocking ... int status = pthread_mutex_lock(_mutex); assert_status(status == 0, status, "mutex_lock"); guarantee(_nParked == 0, "invariant"); ++_nParked; while (_Event < 0) { status = pthread_cond_wait(_cond, _mutex); // for some reason, under 2.7 lwp_cond_wait() may return ETIME ... // Treat this the same as if the wait was interrupted if (status == ETIMEDOUT) { status = EINTR; } assert_status(status == 0 || status == EINTR, status, "cond_wait"); } --_nParked; _Event = 0; status = pthread_mutex_unlock(_mutex); assert_status(status == 0, status, "mutex_unlock"); // Paranoia to ensure our locked and lock-free paths interact // correctly with each other. OrderAccess::fence(); } guarantee(_Event >= 0, "invariant"); } int os::PlatformEvent::park(jlong millis) { guarantee(_nParked == 0, "invariant"); int v; for (;;) { v = _Event; if (Atomic::cmpxchg(v-1, &_Event, v) == v) break; } guarantee(v >= 0, "invariant"); if (v != 0) return OS_OK; // We do this the hard way, by blocking the thread. // Consider enforcing a minimum timeout value. struct timespec abst; compute_abstime(&abst, millis); int ret = OS_TIMEOUT; int status = pthread_mutex_lock(_mutex); assert_status(status == 0, status, "mutex_lock"); guarantee(_nParked == 0, "invariant"); ++_nParked; // Object.wait(timo) will return because of // (a) notification // (b) timeout // (c) thread.interrupt // // Thread.interrupt and object.notify{All} both call Event::set. // That is, we treat thread.interrupt as a special case of notification. // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false. // We assume all ETIME returns are valid. // // TODO: properly differentiate simultaneous notify+interrupt. // In that case, we should propagate the notify to another waiter. while (_Event < 0) { status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst); if (status != 0 && WorkAroundNPTLTimedWaitHang) { pthread_cond_destroy(_cond); pthread_cond_init(_cond, NULL); } assert_status(status == 0 || status == EINTR || status == ETIMEDOUT, status, "cond_timedwait"); if (!FilterSpuriousWakeups) break; // previous semantics if (status == ETIMEDOUT) break; // We consume and ignore EINTR and spurious wakeups. } --_nParked; if (_Event >= 0) { ret = OS_OK; } _Event = 0; status = pthread_mutex_unlock(_mutex); assert_status(status == 0, status, "mutex_unlock"); assert(_nParked == 0, "invariant"); // Paranoia to ensure our locked and lock-free paths interact // correctly with each other. OrderAccess::fence(); return ret; } void os::PlatformEvent::unpark() { // Transitions for _Event: // 0 :=> 1 // 1 :=> 1 // -1 :=> either 0 or 1; must signal target thread // That is, we can safely transition _Event from -1 to either // 0 or 1. // See also: "Semaphores in Plan 9" by Mullender & Cox // // Note: Forcing a transition from "-1" to "1" on an unpark() means // that it will take two back-to-back park() calls for the owning // thread to block. This has the benefit of forcing a spurious return // from the first park() call after an unpark() call which will help // shake out uses of park() and unpark() without condition variables. if (Atomic::xchg(1, &_Event) >= 0) return; // Wait for the thread associated with the event to vacate int status = pthread_mutex_lock(_mutex); assert_status(status == 0, status, "mutex_lock"); int AnyWaiters = _nParked; assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant"); if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) { AnyWaiters = 0; pthread_cond_signal(_cond); } status = pthread_mutex_unlock(_mutex); assert_status(status == 0, status, "mutex_unlock"); if (AnyWaiters != 0) { status = pthread_cond_signal(_cond); assert_status(status == 0, status, "cond_signal"); } // Note that we signal() _after dropping the lock for "immortal" Events. // This is safe and avoids a common class of futile wakeups. In rare // circumstances this can cause a thread to return prematurely from // cond_{timed}wait() but the spurious wakeup is benign and the victim will // simply re-test the condition and re-park itself. } // JSR166 // ------------------------------------------------------- /* * The solaris and bsd implementations of park/unpark are fairly * conservative for now, but can be improved. They currently use a * mutex/condvar pair, plus a a count. * Park decrements count if > 0, else does a condvar wait. Unpark * sets count to 1 and signals condvar. Only one thread ever waits * on the condvar. Contention seen when trying to park implies that someone * is unparking you, so don't wait. And spurious returns are fine, so there * is no need to track notifications. */ #define MAX_SECS 100000000 /* * This code is common to bsd and solaris and will be moved to a * common place in dolphin. * * The passed in time value is either a relative time in nanoseconds * or an absolute time in milliseconds. Either way it has to be unpacked * into suitable seconds and nanoseconds components and stored in the * given timespec structure. * Given time is a 64-bit value and the time_t used in the timespec is only * a signed-32-bit value (except on 64-bit Bsd) we have to watch for * overflow if times way in the future are given. Further on Solaris versions * prior to 10 there is a restriction (see cond_timedwait) that the specified * number of seconds, in abstime, is less than current_time + 100,000,000. * As it will be 28 years before "now + 100000000" will overflow we can * ignore overflow and just impose a hard-limit on seconds using the value * of "now + 100,000,000". This places a limit on the timeout of about 3.17 * years from "now". */ static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) { assert(time > 0, "convertTime"); struct timeval now; int status = gettimeofday(&now, NULL); assert(status == 0, "gettimeofday"); time_t max_secs = now.tv_sec + MAX_SECS; if (isAbsolute) { jlong secs = time / 1000; if (secs > max_secs) { absTime->tv_sec = max_secs; } else { absTime->tv_sec = secs; } absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC; } else { jlong secs = time / NANOSECS_PER_SEC; if (secs >= MAX_SECS) { absTime->tv_sec = max_secs; absTime->tv_nsec = 0; } else { absTime->tv_sec = now.tv_sec + secs; absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000; if (absTime->tv_nsec >= NANOSECS_PER_SEC) { absTime->tv_nsec -= NANOSECS_PER_SEC; ++absTime->tv_sec; // note: this must be <= max_secs } } } assert(absTime->tv_sec >= 0, "tv_sec < 0"); assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs"); assert(absTime->tv_nsec >= 0, "tv_nsec < 0"); assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec"); } void Parker::park(bool isAbsolute, jlong time) { // Ideally we'd do something useful while spinning, such // as calling unpackTime(). // Optional fast-path check: // Return immediately if a permit is available. // We depend on Atomic::xchg() having full barrier semantics // since we are doing a lock-free update to _counter. if (Atomic::xchg(0, &_counter) > 0) return; Thread* thread = Thread::current(); assert(thread->is_Java_thread(), "Must be JavaThread"); JavaThread *jt = (JavaThread *)thread; // Optional optimization -- avoid state transitions if there's an interrupt pending. // Check interrupt before trying to wait if (Thread::is_interrupted(thread, false)) { return; } // Next, demultiplex/decode time arguments struct timespec absTime; if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all return; } if (time > 0) { unpackTime(&absTime, isAbsolute, time); } // Enter safepoint region // Beware of deadlocks such as 6317397. // The per-thread Parker:: mutex is a classic leaf-lock. // In particular a thread must never block on the Threads_lock while // holding the Parker:: mutex. If safepoints are pending both the // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock. ThreadBlockInVM tbivm(jt); // Don't wait if cannot get lock since interference arises from // unblocking. Also. check interrupt before trying wait if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) { return; } int status; if (_counter > 0) { // no wait needed _counter = 0; status = pthread_mutex_unlock(_mutex); assert(status == 0, "invariant"); // Paranoia to ensure our locked and lock-free paths interact // correctly with each other and Java-level accesses. OrderAccess::fence(); return; } #ifdef ASSERT // Don't catch signals while blocked; let the running threads have the signals. // (This allows a debugger to break into the running thread.) sigset_t oldsigs; sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals(); pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs); #endif OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */); jt->set_suspend_equivalent(); // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self() if (time == 0) { status = pthread_cond_wait(_cond, _mutex); } else { status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &absTime); if (status != 0 && WorkAroundNPTLTimedWaitHang) { pthread_cond_destroy(_cond); pthread_cond_init(_cond, NULL); } } assert_status(status == 0 || status == EINTR || status == ETIMEDOUT, status, "cond_timedwait"); #ifdef ASSERT pthread_sigmask(SIG_SETMASK, &oldsigs, NULL); #endif _counter = 0; status = pthread_mutex_unlock(_mutex); assert_status(status == 0, status, "invariant"); // Paranoia to ensure our locked and lock-free paths interact // correctly with each other and Java-level accesses. OrderAccess::fence(); // If externally suspended while waiting, re-suspend if (jt->handle_special_suspend_equivalent_condition()) { jt->java_suspend_self(); } } void Parker::unpark() { int status = pthread_mutex_lock(_mutex); assert(status == 0, "invariant"); const int s = _counter; _counter = 1; if (s < 1) { if (WorkAroundNPTLTimedWaitHang) { status = pthread_cond_signal(_cond); assert(status == 0, "invariant"); status = pthread_mutex_unlock(_mutex); assert(status == 0, "invariant"); } else { status = pthread_mutex_unlock(_mutex); assert(status == 0, "invariant"); status = pthread_cond_signal(_cond); assert(status == 0, "invariant"); } } else { pthread_mutex_unlock(_mutex); assert(status == 0, "invariant"); } } /* Darwin has no "environ" in a dynamic library. */ #ifdef __APPLE__ #include #define environ (*_NSGetEnviron()) #else extern char** environ; #endif // Run the specified command in a separate process. Return its exit value, // or -1 on failure (e.g. can't fork a new process). // Unlike system(), this function can be called from signal handler. It // doesn't block SIGINT et al. int os::fork_and_exec(char* cmd) { const char * argv[4] = {"sh", "-c", cmd, NULL}; // fork() in BsdThreads/NPTL is not async-safe. It needs to run // pthread_atfork handlers and reset pthread library. All we need is a // separate process to execve. Make a direct syscall to fork process. // On IA64 there's no fork syscall, we have to use fork() and hope for // the best... pid_t pid = fork(); if (pid < 0) { // fork failed return -1; } else if (pid == 0) { // child process // execve() in BsdThreads will call pthread_kill_other_threads_np() // first to kill every thread on the thread list. Because this list is // not reset by fork() (see notes above), execve() will instead kill // every thread in the parent process. We know this is the only thread // in the new process, so make a system call directly. // IA64 should use normal execve() from glibc to match the glibc fork() // above. execve("/bin/sh", (char* const*)argv, environ); // execve failed _exit(-1); } else { // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't // care about the actual exit code, for now. int status; // Wait for the child process to exit. This returns immediately if // the child has already exited. */ while (waitpid(pid, &status, 0) < 0) { switch (errno) { case ECHILD: return 0; case EINTR: break; default: return -1; } } if (WIFEXITED(status)) { // The child exited normally; get its exit code. return WEXITSTATUS(status); } else if (WIFSIGNALED(status)) { // The child exited because of a signal // The best value to return is 0x80 + signal number, // because that is what all Unix shells do, and because // it allows callers to distinguish between process exit and // process death by signal. return 0x80 + WTERMSIG(status); } else { // Unknown exit code; pass it through return status; } } } // is_headless_jre() // // Test for the existence of xawt/libmawt.so or libawt_xawt.so // in order to report if we are running in a headless jre // // Since JDK8 xawt/libmawt.so was moved into the same directory // as libawt.so, and renamed libawt_xawt.so // bool os::is_headless_jre() { #ifdef __APPLE__ // We no longer build headless-only on Mac OS X return false; #else struct stat statbuf; char buf[MAXPATHLEN]; char libmawtpath[MAXPATHLEN]; const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX; const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX; char *p; // Get path to libjvm.so os::jvm_path(buf, sizeof(buf)); // Get rid of libjvm.so p = strrchr(buf, '/'); if (p == NULL) return false; else *p = '\0'; // Get rid of client or server p = strrchr(buf, '/'); if (p == NULL) return false; else *p = '\0'; // check xawt/libmawt.so strcpy(libmawtpath, buf); strcat(libmawtpath, xawtstr); if (::stat(libmawtpath, &statbuf) == 0) return false; // check libawt_xawt.so strcpy(libmawtpath, buf); strcat(libmawtpath, new_xawtstr); if (::stat(libmawtpath, &statbuf) == 0) return false; return true; #endif } // Get the default path to the core file // Returns the length of the string int os::get_core_path(char* buffer, size_t bufferSize) { int n = jio_snprintf(buffer, bufferSize, "/cores"); // Truncate if theoretical string was longer than bufferSize n = MIN2(n, (int)bufferSize); return n; } #ifndef PRODUCT void TestReserveMemorySpecial_test() { // No tests available for this platform } #endif