8026324: hs_err improvement: Add summary section to hs_err file
8026333: hs_err improvement: Print GC Strategy
8026336: hs_err improvement: Print compilation mode, server, client or tiered
Summary: Added command line, summary cpu and os information to summary section. Moved time of crash and duration in summary section. Add GC strategy and compiler setting (tiered) to enhanced version string in error report. Moved the stack trace sooner in hs_err file.
Reviewed-by: dholmes, ctornqvi, ddmitriev
/*
* Copyright (c) 1999, 2015, 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 "semaphore_bsd.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 <sys/types.h>
# include <sys/mman.h>
# include <sys/stat.h>
# include <sys/select.h>
# include <pthread.h>
# include <signal.h>
# include <errno.h>
# include <dlfcn.h>
# include <stdio.h>
# include <unistd.h>
# include <sys/resource.h>
# include <pthread.h>
# include <sys/stat.h>
# include <sys/time.h>
# include <sys/times.h>
# include <sys/utsname.h>
# include <sys/socket.h>
# include <sys/wait.h>
# include <time.h>
# include <pwd.h>
# include <poll.h>
# include <semaphore.h>
# include <fcntl.h>
# include <string.h>
# include <sys/param.h>
# include <sys/sysctl.h>
# include <sys/ipc.h>
# include <sys/shm.h>
#ifndef __APPLE__
# include <link.h>
#endif
# include <stdint.h>
# include <inttypes.h>
# include <sys/ioctl.h>
# include <sys/syscall.h>
#if defined(__FreeBSD__) || defined(__NetBSD__)
#include <elf.h>
#endif
#ifdef __APPLE__
#include <mach/mach.h> // semaphore_* API
#include <mach-o/dyld.h>
#include <sys/proc_info.h>
#include <objc/objc-auto.h>
#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();
}
// 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:
// <JAVA_HOME>/jre/lib/<arch>/{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/<arch>,
// then we append a fake suffix "hotspot/libjvm.so" to this path so
// it looks like libjvm.so is installed there
// <JAVA_HOME>/jre/lib/<arch>/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"
#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 =
MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
(size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions 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 <java_home>/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 /<arch>.
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);
}
// Extensions directories.
sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
Arguments::set_ext_dirs(buf);
FREE_C_HEAP_ARRAY(char, buf);
#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 =
MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
(size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions 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 <java_home>/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);
}
// 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);
FREE_C_HEAP_ARRAY(char, buf);
#undef SYS_EXTENSIONS_DIR
#undef SYS_EXTENSIONS_DIRS
#endif // __APPLE__
#undef SYS_EXT_DIR
#undef EXTENSIONS_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
#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();
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);
}
void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
timeval time;
int status = gettimeofday(&time, NULL);
assert(status != -1, "bsd error");
seconds = jlong(time.tv_sec);
nanos = 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, void* siginfo, void* context) {
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;
#else
#ifdef __FreeBSD__
retval = syscall(SYS_thr_self);
#else
#ifdef __OpenBSD__
retval = syscall(SYS_getthrid);
#else
#ifdef __NetBSD__
retval = (pid_t) syscall(SYS__lwp_self);
#endif
#endif
#endif
#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]);
}
}
if (pelements != NULL) {
FREE_C_HEAP_ARRAY(char*, pelements);
}
} 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,
bool demangle) {
// 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 (!(demangle && 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, demangle)) {
return true;
}
}
// Handle non-dynamic manually:
if (dlinfo.dli_fbase != NULL &&
Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
dlinfo.dli_fbase)) {
if (!(demangle && 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);
}
int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
outputStream * out = (outputStream *) param;
out->print_cr(PTR_FORMAT " \t%s", base_address, name);
return 0;
}
void os::print_dll_info(outputStream *st) {
st->print_cr("Dynamic libraries:");
if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
st->print_cr("Error: Cannot print dynamic libraries.");
}
}
int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
#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) {
return 1;
}
handle = dlopen(dli.dli_fname, RTLD_LAZY);
if (handle == NULL) {
return 1;
}
dlinfo(handle, RTLD_DI_LINKMAP, &map);
if (map == NULL) {
dlclose(handle);
return 1;
}
while (map->l_prev != NULL)
map = map->l_prev;
while (map != NULL) {
// Value for top_address is returned as 0 since we don't have any information about module size
if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
dlclose(handle);
return 1;
}
map = map->l_next;
}
dlclose(handle);
#elif defined(__APPLE__)
for (uint32_t i = 1; i < _dyld_image_count(); i++) {
// Value for top_address is returned as 0 since we don't have any information about module size
if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
return 1;
}
}
return 0;
#else
return 1;
#endif
}
void os::get_summary_os_info(char* buf, size_t buflen) {
// These buffers are small because we want this to be brief
// and not use a lot of stack while generating the hs_err file.
char os[100];
size_t size = sizeof(os);
int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
#ifdef __APPLE__
strncpy(os, "Darwin", sizeof(os));
#elif __OpenBSD__
strncpy(os, "OpenBSD", sizeof(os));
#else
strncpy(os, "BSD", sizeof(os));
#endif
}
char release[100];
size = sizeof(release);
int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
// if error, leave blank
strncpy(release, "", sizeof(release));
}
snprintf(buf, buflen, "%s %s", os, release);
}
void os::print_os_info_brief(outputStream* st) {
os::Posix::print_uname_info(st);
}
void os::print_os_info(outputStream* st) {
st->print("OS:");
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, char* buf, size_t buflen) {
// Nothing to do for now.
}
void os::get_summary_cpu_info(char* buf, size_t buflen) {
unsigned int mhz;
size_t size = sizeof(mhz);
int mib[] = { CTL_HW, HW_CPU_FREQ };
if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
mhz = 1; // looks like an error but can be divided by
} else {
mhz /= 1000000; // reported in millions
}
char model[100];
size = sizeof(model);
int mib_model[] = { CTL_HW, HW_MODEL };
if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
strncpy(model, cpu_arch, sizeof(model));
}
char machine[100];
size = sizeof(machine);
int mib_machine[] = { CTL_HW, HW_MACHINE };
if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
strncpy(machine, "", sizeof(machine));
}
snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
}
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();
}
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=<path>' option. Typical
// value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
// or "<JAVA_HOME>/jre/lib/<vmtype>/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);
saved_jvm_path[MAXPATHLEN - 1] = '\0';
}
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
#ifdef __APPLE__
// OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
static const char* sem_init_strerror(kern_return_t value) {
switch (value) {
case KERN_INVALID_ARGUMENT: return "Invalid argument";
case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
default: return "Unknown";
}
}
OSXSemaphore::OSXSemaphore(uint value) {
kern_return_t ret = SEM_INIT(_semaphore, value);
guarantee(ret == KERN_SUCCESS, err_msg("Failed to create semaphore: %s", sem_init_strerror(ret)));
}
OSXSemaphore::~OSXSemaphore() {
SEM_DESTROY(_semaphore);
}
void OSXSemaphore::signal(uint count) {
for (uint i = 0; i < count; i++) {
kern_return_t ret = SEM_POST(_semaphore);
assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
}
}
void OSXSemaphore::wait() {
kern_return_t ret;
while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
// Semaphore was interrupted. Retry.
}
assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
}
jlong OSXSemaphore::currenttime() {
struct timeval tv;
gettimeofday(&tv, NULL);
return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
}
bool OSXSemaphore::trywait() {
return timedwait(0, 0);
}
bool OSXSemaphore::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
// Use POSIX implementation of semaphores.
struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
struct timespec ts;
unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
return ts;
}
#endif // __APPLE__
static os_semaphore_t sig_sem;
#ifdef __APPLE__
static OSXSemaphore sr_semaphore;
#else
static PosixSemaphore sr_semaphore;
#endif
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);
}
// 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);
return addr == MAP_FAILED ? NULL : addr;
}
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.
// 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) {
return requested_addr;
} else {
return NULL;
}
}
size_t os::read(int fd, void *buf, unsigned int nBytes) {
RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
}
size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
}
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) \
do { \
if (!sigismember(&check_signal_done, sig)) { \
os::Bsd::check_signal_handler(sig); \
} \
} while (0)
// 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;
}
// 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();
}
////////////////////////////////////////////////////////////////////////////////
// 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("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
} else {
st->print("<absolute address>");
}
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;
}
// 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
int os::open(const char *path, int oflag, int mode) {
if (strlen(path) > MAX_PATH - 1) {
errno = ENAMETOOLONG;
return -1;
}
int fd;
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
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;
}
// 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. The next two
// comment paragraphs are worth repeating here:
//
// Assumption:
// Only one parker can exist on an event, which is why we allocate
// them per-thread. Multiple unparkers can coexist.
//
// _Event serves as a restricted-range semaphore.
// -1 : thread is blocked, i.e. there is a waiter
// 0 : neutral: thread is running or ready,
// could have been signaled after a wait started
// 1 : signaled - thread is running or ready
//
// 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()"
// Transitions for _Event:
// -1 => -1 : illegal
// 1 => 0 : pass - return immediately
// 0 => -1 : block; then set _Event to 0 before returning
// 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) {
// Transitions for _Event:
// -1 => -1 : illegal
// 1 => 0 : pass - return immediately
// 0 => -1 : block; then set _Event to 0 before returning
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 = pthread_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 : just return
// 1 => 1 : just return
// -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) {
// 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.
// This provides particular benefit if the underlying platform does not
// provide wait morphing.
status = pthread_cond_signal(_cond);
assert_status(status == 0, status, "cond_signal");
}
}
// 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 = pthread_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 <crt_externs.h>
#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/core.%d", current_process_id());
// 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