Java example source code file (os.cpp)
The os.cpp Java example source code/*
* Copyright (c) 1997, 2013, 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.
*
*/
#include "precompiled.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/icBuffer.hpp"
#include "code/vtableStubs.hpp"
#include "gc_implementation/shared/vmGCOperations.hpp"
#include "interpreter/interpreter.hpp"
#include "memory/allocation.inline.hpp"
#include "oops/oop.inline.hpp"
#include "prims/jvm.h"
#include "prims/jvm_misc.hpp"
#include "prims/privilegedStack.hpp"
#include "runtime/arguments.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/interfaceSupport.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/os.hpp"
#include "runtime/stubRoutines.hpp"
#include "runtime/thread.inline.hpp"
#include "services/attachListener.hpp"
#include "services/memTracker.hpp"
#include "services/threadService.hpp"
#include "utilities/defaultStream.hpp"
#include "utilities/events.hpp"
#ifdef TARGET_OS_FAMILY_linux
# include "os_linux.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_solaris
# include "os_solaris.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_windows
# include "os_windows.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_bsd
# include "os_bsd.inline.hpp"
#endif
# include <signal.h>
OSThread* os::_starting_thread = NULL;
address os::_polling_page = NULL;
volatile int32_t* os::_mem_serialize_page = NULL;
uintptr_t os::_serialize_page_mask = 0;
long os::_rand_seed = 1;
int os::_processor_count = 0;
size_t os::_page_sizes[os::page_sizes_max];
#ifndef PRODUCT
julong os::num_mallocs = 0; // # of calls to malloc/realloc
julong os::alloc_bytes = 0; // # of bytes allocated
julong os::num_frees = 0; // # of calls to free
julong os::free_bytes = 0; // # of bytes freed
#endif
static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
void os_init_globals() {
// Called from init_globals().
// See Threads::create_vm() in thread.cpp, and init.cpp.
os::init_globals();
}
// Fill in buffer with current local time as an ISO-8601 string.
// E.g., yyyy-mm-ddThh:mm:ss-zzzz.
// Returns buffer, or NULL if it failed.
// This would mostly be a call to
// strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
// except that on Windows the %z behaves badly, so we do it ourselves.
// Also, people wanted milliseconds on there,
// and strftime doesn't do milliseconds.
char* os::iso8601_time(char* buffer, size_t buffer_length) {
// Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
// 1 2
// 12345678901234567890123456789
static const char* iso8601_format =
"%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
static const size_t needed_buffer = 29;
// Sanity check the arguments
if (buffer == NULL) {
assert(false, "NULL buffer");
return NULL;
}
if (buffer_length < needed_buffer) {
assert(false, "buffer_length too small");
return NULL;
}
// Get the current time
jlong milliseconds_since_19700101 = javaTimeMillis();
const int milliseconds_per_microsecond = 1000;
const time_t seconds_since_19700101 =
milliseconds_since_19700101 / milliseconds_per_microsecond;
const int milliseconds_after_second =
milliseconds_since_19700101 % milliseconds_per_microsecond;
// Convert the time value to a tm and timezone variable
struct tm time_struct;
if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
assert(false, "Failed localtime_pd");
return NULL;
}
#if defined(_ALLBSD_SOURCE)
const time_t zone = (time_t) time_struct.tm_gmtoff;
#else
const time_t zone = timezone;
#endif
// If daylight savings time is in effect,
// we are 1 hour East of our time zone
const time_t seconds_per_minute = 60;
const time_t minutes_per_hour = 60;
const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
time_t UTC_to_local = zone;
if (time_struct.tm_isdst > 0) {
UTC_to_local = UTC_to_local - seconds_per_hour;
}
// Compute the time zone offset.
// localtime_pd() sets timezone to the difference (in seconds)
// between UTC and and local time.
// ISO 8601 says we need the difference between local time and UTC,
// we change the sign of the localtime_pd() result.
const time_t local_to_UTC = -(UTC_to_local);
// Then we have to figure out if if we are ahead (+) or behind (-) UTC.
char sign_local_to_UTC = '+';
time_t abs_local_to_UTC = local_to_UTC;
if (local_to_UTC < 0) {
sign_local_to_UTC = '-';
abs_local_to_UTC = -(abs_local_to_UTC);
}
// Convert time zone offset seconds to hours and minutes.
const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
const time_t zone_min =
((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
// Print an ISO 8601 date and time stamp into the buffer
const int year = 1900 + time_struct.tm_year;
const int month = 1 + time_struct.tm_mon;
const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
year,
month,
time_struct.tm_mday,
time_struct.tm_hour,
time_struct.tm_min,
time_struct.tm_sec,
milliseconds_after_second,
sign_local_to_UTC,
zone_hours,
zone_min);
if (printed == 0) {
assert(false, "Failed jio_printf");
return NULL;
}
return buffer;
}
OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
#ifdef ASSERT
if (!(!thread->is_Java_thread() ||
Thread::current() == thread ||
Threads_lock->owned_by_self()
|| thread->is_Compiler_thread()
)) {
assert(false, "possibility of dangling Thread pointer");
}
#endif
if (p >= MinPriority && p <= MaxPriority) {
int priority = java_to_os_priority[p];
return set_native_priority(thread, priority);
} else {
assert(false, "Should not happen");
return OS_ERR;
}
}
// The mapping from OS priority back to Java priority may be inexact because
// Java priorities can map M:1 with native priorities. If you want the definite
// Java priority then use JavaThread::java_priority()
OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
int p;
int os_prio;
OSReturn ret = get_native_priority(thread, &os_prio);
if (ret != OS_OK) return ret;
if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
} else {
// niceness values are in reverse order
for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
}
priority = (ThreadPriority)p;
return OS_OK;
}
// --------------------- sun.misc.Signal (optional) ---------------------
// SIGBREAK is sent by the keyboard to query the VM state
#ifndef SIGBREAK
#define SIGBREAK SIGQUIT
#endif
// sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
static void signal_thread_entry(JavaThread* thread, TRAPS) {
os::set_priority(thread, NearMaxPriority);
while (true) {
int sig;
{
// FIXME : Currently we have not decieded what should be the status
// for this java thread blocked here. Once we decide about
// that we should fix this.
sig = os::signal_wait();
}
if (sig == os::sigexitnum_pd()) {
// Terminate the signal thread
return;
}
switch (sig) {
case SIGBREAK: {
// Check if the signal is a trigger to start the Attach Listener - in that
// case don't print stack traces.
if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
continue;
}
// Print stack traces
// Any SIGBREAK operations added here should make sure to flush
// the output stream (e.g. tty->flush()) after output. See 4803766.
// Each module also prints an extra carriage return after its output.
VM_PrintThreads op;
VMThread::execute(&op);
VM_PrintJNI jni_op;
VMThread::execute(&jni_op);
VM_FindDeadlocks op1(tty);
VMThread::execute(&op1);
Universe::print_heap_at_SIGBREAK();
if (PrintClassHistogram) {
VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
VMThread::execute(&op1);
}
if (JvmtiExport::should_post_data_dump()) {
JvmtiExport::post_data_dump();
}
break;
}
default: {
// Dispatch the signal to java
HandleMark hm(THREAD);
Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
KlassHandle klass (THREAD, k);
if (klass.not_null()) {
JavaValue result(T_VOID);
JavaCallArguments args;
args.push_int(sig);
JavaCalls::call_static(
&result,
klass,
vmSymbols::dispatch_name(),
vmSymbols::int_void_signature(),
&args,
THREAD
);
}
if (HAS_PENDING_EXCEPTION) {
// tty is initialized early so we don't expect it to be null, but
// if it is we can't risk doing an initialization that might
// trigger additional out-of-memory conditions
if (tty != NULL) {
char klass_name[256];
char tmp_sig_name[16];
const char* sig_name = "UNKNOWN";
InstanceKlass::cast(PENDING_EXCEPTION->klass())->
name()->as_klass_external_name(klass_name, 256);
if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
sig_name = tmp_sig_name;
warning("Exception %s occurred dispatching signal %s to handler"
"- the VM may need to be forcibly terminated",
klass_name, sig_name );
}
CLEAR_PENDING_EXCEPTION;
}
}
}
}
}
void os::init_before_ergo() {
// We need to initialize large page support here because ergonomics takes some
// decisions depending on large page support and the calculated large page size.
large_page_init();
}
void os::signal_init() {
if (!ReduceSignalUsage) {
// Setup JavaThread for processing signals
EXCEPTION_MARK;
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
instanceKlassHandle klass (THREAD, k);
instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
const char thread_name[] = "Signal Dispatcher";
Handle string = java_lang_String::create_from_str(thread_name, CHECK);
// Initialize thread_oop to put it into the system threadGroup
Handle thread_group (THREAD, Universe::system_thread_group());
JavaValue result(T_VOID);
JavaCalls::call_special(&result, thread_oop,
klass,
vmSymbols::object_initializer_name(),
vmSymbols::threadgroup_string_void_signature(),
thread_group,
string,
CHECK);
KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
JavaCalls::call_special(&result,
thread_group,
group,
vmSymbols::add_method_name(),
vmSymbols::thread_void_signature(),
thread_oop, // ARG 1
CHECK);
os::signal_init_pd();
{ MutexLocker mu(Threads_lock);
JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
// At this point it may be possible that no osthread was created for the
// JavaThread due to lack of memory. We would have to throw an exception
// in that case. However, since this must work and we do not allow
// exceptions anyway, check and abort if this fails.
if (signal_thread == NULL || signal_thread->osthread() == NULL) {
vm_exit_during_initialization("java.lang.OutOfMemoryError",
"unable to create new native thread");
}
java_lang_Thread::set_thread(thread_oop(), signal_thread);
java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
java_lang_Thread::set_daemon(thread_oop());
signal_thread->set_threadObj(thread_oop());
Threads::add(signal_thread);
Thread::start(signal_thread);
}
// Handle ^BREAK
os::signal(SIGBREAK, os::user_handler());
}
}
void os::terminate_signal_thread() {
if (!ReduceSignalUsage)
signal_notify(sigexitnum_pd());
}
// --------------------- loading libraries ---------------------
typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
extern struct JavaVM_ main_vm;
static void* _native_java_library = NULL;
void* os::native_java_library() {
if (_native_java_library == NULL) {
char buffer[JVM_MAXPATHLEN];
char ebuf[1024];
// Try to load verify dll first. In 1.3 java dll depends on it and is not
// always able to find it when the loading executable is outside the JDK.
// In order to keep working with 1.2 we ignore any loading errors.
if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
"verify")) {
dll_load(buffer, ebuf, sizeof(ebuf));
}
// Load java dll
if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
"java")) {
_native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
}
if (_native_java_library == NULL) {
vm_exit_during_initialization("Unable to load native library", ebuf);
}
#if defined(__OpenBSD__)
// Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
// ignore errors
if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
"net")) {
dll_load(buffer, ebuf, sizeof(ebuf));
}
#endif
}
static jboolean onLoaded = JNI_FALSE;
if (onLoaded) {
// We may have to wait to fire OnLoad until TLS is initialized.
if (ThreadLocalStorage::is_initialized()) {
// The JNI_OnLoad handling is normally done by method load in
// java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
// explicitly so we have to check for JNI_OnLoad as well
const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
if (JNI_OnLoad != NULL) {
JavaThread* thread = JavaThread::current();
ThreadToNativeFromVM ttn(thread);
HandleMark hm(thread);
jint ver = (*JNI_OnLoad)(&main_vm, NULL);
onLoaded = JNI_TRUE;
if (!Threads::is_supported_jni_version_including_1_1(ver)) {
vm_exit_during_initialization("Unsupported JNI version");
}
}
}
}
return _native_java_library;
}
/*
* Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
* If check_lib == true then we are looking for an
* Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
* this library is statically linked into the image.
* If check_lib == false then we will look for the appropriate symbol in the
* executable if agent_lib->is_static_lib() == true or in the shared library
* referenced by 'handle'.
*/
void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
const char *syms[], size_t syms_len) {
assert(agent_lib != NULL, "sanity check");
const char *lib_name;
void *handle = agent_lib->os_lib();
void *entryName = NULL;
char *agent_function_name;
size_t i;
// If checking then use the agent name otherwise test is_static_lib() to
// see how to process this lookup
lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
for (i = 0; i < syms_len; i++) {
agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
if (agent_function_name == NULL) {
break;
}
entryName = dll_lookup(handle, agent_function_name);
FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
if (entryName != NULL) {
break;
}
}
return entryName;
}
// See if the passed in agent is statically linked into the VM image.
bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
size_t syms_len) {
void *ret;
void *proc_handle;
void *save_handle;
assert(agent_lib != NULL, "sanity check");
if (agent_lib->name() == NULL) {
return false;
}
proc_handle = get_default_process_handle();
// Check for Agent_OnLoad/Attach_lib_name function
save_handle = agent_lib->os_lib();
// We want to look in this process' symbol table.
agent_lib->set_os_lib(proc_handle);
ret = find_agent_function(agent_lib, true, syms, syms_len);
if (ret != NULL) {
// Found an entry point like Agent_OnLoad_lib_name so we have a static agent
agent_lib->set_valid();
agent_lib->set_static_lib(true);
return true;
}
agent_lib->set_os_lib(save_handle);
return false;
}
// --------------------- heap allocation utilities ---------------------
char *os::strdup(const char *str, MEMFLAGS flags) {
size_t size = strlen(str);
char *dup_str = (char *)malloc(size + 1, flags);
if (dup_str == NULL) return NULL;
strcpy(dup_str, str);
return dup_str;
}
#ifdef ASSERT
#define space_before (MallocCushion + sizeof(double))
#define space_after MallocCushion
#define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
#define size_addr_from_obj(p) ((size_t*)p - 1)
// MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
// NB: cannot be debug variable, because these aren't set from the command line until
// *after* the first few allocs already happened
#define MallocCushion 16
#else
#define space_before 0
#define space_after 0
#define size_addr_from_base(p) should not use w/o ASSERT
#define size_addr_from_obj(p) should not use w/o ASSERT
#define MallocCushion 0
#endif
#define paranoid 0 /* only set to 1 if you suspect checking code has bug */
#ifdef ASSERT
inline size_t get_size(void* obj) {
size_t size = *size_addr_from_obj(obj);
if (size < 0) {
fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
SIZE_FORMAT ")", obj, size));
}
return size;
}
u_char* find_cushion_backwards(u_char* start) {
u_char* p = start;
while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
// ok, we have four consecutive marker bytes; find start
u_char* q = p - 4;
while (*q == badResourceValue) q--;
return q + 1;
}
u_char* find_cushion_forwards(u_char* start) {
u_char* p = start;
while (p[0] != badResourceValue || p[1] != badResourceValue ||
p[2] != badResourceValue || p[3] != badResourceValue) p++;
// ok, we have four consecutive marker bytes; find end of cushion
u_char* q = p + 4;
while (*q == badResourceValue) q++;
return q - MallocCushion;
}
void print_neighbor_blocks(void* ptr) {
// find block allocated before ptr (not entirely crash-proof)
if (MallocCushion < 4) {
tty->print_cr("### cannot find previous block (MallocCushion < 4)");
return;
}
u_char* start_of_this_block = (u_char*)ptr - space_before;
u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
// look for cushion in front of prev. block
u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
u_char* obj = start_of_prev_block + space_before;
if (size <= 0 ) {
// start is bad; mayhave been confused by OS data inbetween objects
// search one more backwards
start_of_prev_block = find_cushion_backwards(start_of_prev_block);
size = *size_addr_from_base(start_of_prev_block);
obj = start_of_prev_block + space_before;
}
if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
} else {
tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
}
// now find successor block
u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
start_of_next_block = find_cushion_forwards(start_of_next_block);
u_char* next_obj = start_of_next_block + space_before;
ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
if (start_of_next_block[0] == badResourceValue &&
start_of_next_block[1] == badResourceValue &&
start_of_next_block[2] == badResourceValue &&
start_of_next_block[3] == badResourceValue) {
tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
} else {
tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
}
}
void report_heap_error(void* memblock, void* bad, const char* where) {
tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
print_neighbor_blocks(memblock);
fatal("memory stomping error");
}
void verify_block(void* memblock) {
size_t size = get_size(memblock);
if (MallocCushion) {
u_char* ptr = (u_char*)memblock - space_before;
for (int i = 0; i < MallocCushion; i++) {
if (ptr[i] != badResourceValue) {
report_heap_error(memblock, ptr+i, "in front of");
}
}
u_char* end = (u_char*)memblock + size + space_after;
for (int j = -MallocCushion; j < 0; j++) {
if (end[j] != badResourceValue) {
report_heap_error(memblock, end+j, "after");
}
}
}
}
#endif
//
// This function supports testing of the malloc out of memory
// condition without really running the system out of memory.
//
static u_char* testMalloc(size_t alloc_size) {
assert(MallocMaxTestWords > 0, "sanity check");
if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
return NULL;
}
u_char* ptr = (u_char*)::malloc(alloc_size);
if (ptr != NULL) {
Atomic::add(((jint) (alloc_size / BytesPerWord)),
(volatile jint *) &cur_malloc_words);
}
return ptr;
}
void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
#ifdef ASSERT
// checking for the WatcherThread and crash_protection first
// since os::malloc can be called when the libjvm.{dll,so} is
// first loaded and we don't have a thread yet.
// try to find the thread after we see that the watcher thread
// exists and has crash protection.
WatcherThread *wt = WatcherThread::watcher_thread();
if (wt != NULL && wt->has_crash_protection()) {
Thread* thread = ThreadLocalStorage::get_thread_slow();
if (thread == wt) {
assert(!wt->has_crash_protection(),
"Can't malloc with crash protection from WatcherThread");
}
}
#endif
if (size == 0) {
// return a valid pointer if size is zero
// if NULL is returned the calling functions assume out of memory.
size = 1;
}
const size_t alloc_size = size + space_before + space_after;
if (size > alloc_size) { // Check for rollover.
return NULL;
}
NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
u_char* ptr;
if (MallocMaxTestWords > 0) {
ptr = testMalloc(alloc_size);
} else {
ptr = (u_char*)::malloc(alloc_size);
}
#ifdef ASSERT
if (ptr == NULL) return NULL;
if (MallocCushion) {
for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
u_char* end = ptr + space_before + size;
for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
}
// put size just before data
*size_addr_from_base(ptr) = size;
#endif
u_char* memblock = ptr + space_before;
if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
breakpoint();
}
debug_only(if (paranoid) verify_block(memblock));
if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
// we do not track MallocCushion memory
MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
return memblock;
}
void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
#ifndef ASSERT
NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
void* ptr = ::realloc(memblock, size);
if (ptr != NULL) {
tkr.record((address)memblock, (address)ptr, size, memflags,
caller == 0 ? CALLER_PC : caller);
} else {
tkr.discard();
}
return ptr;
#else
if (memblock == NULL) {
return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
}
if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
breakpoint();
}
verify_block(memblock);
NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
if (size == 0) return NULL;
// always move the block
void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
// Copy to new memory if malloc didn't fail
if ( ptr != NULL ) {
memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
if (paranoid) verify_block(ptr);
if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
breakpoint();
}
free(memblock);
}
return ptr;
#endif
}
void os::free(void *memblock, MEMFLAGS memflags) {
NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
#ifdef ASSERT
if (memblock == NULL) return;
if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
breakpoint();
}
verify_block(memblock);
NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
// Added by detlefs.
if (MallocCushion) {
u_char* ptr = (u_char*)memblock - space_before;
for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
guarantee(*p == badResourceValue,
"Thing freed should be malloc result.");
*p = (u_char)freeBlockPad;
}
size_t size = get_size(memblock);
inc_stat_counter(&free_bytes, size);
u_char* end = ptr + space_before + size;
for (u_char* q = end; q < end + MallocCushion; q++) {
guarantee(*q == badResourceValue,
"Thing freed should be malloc result.");
*q = (u_char)freeBlockPad;
}
if (PrintMalloc && tty != NULL)
fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
} else if (PrintMalloc && tty != NULL) {
// tty->print_cr("os::free %p", memblock);
fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
}
#endif
MemTracker::record_free((address)memblock, memflags);
::free((char*)memblock - space_before);
}
void os::init_random(long initval) {
_rand_seed = initval;
}
long os::random() {
/* standard, well-known linear congruential random generator with
* next_rand = (16807*seed) mod (2**31-1)
* see
* (1) "Random Number Generators: Good Ones Are Hard to Find",
* S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
* (2) "Two Fast Implementations of the 'Minimal Standard' Random
* Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
*/
const long a = 16807;
const unsigned long m = 2147483647;
const long q = m / a; assert(q == 127773, "weird math");
const long r = m % a; assert(r == 2836, "weird math");
// compute az=2^31p+q
unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
lo += (hi & 0x7FFF) << 16;
// if q overflowed, ignore the overflow and increment q
if (lo > m) {
lo &= m;
++lo;
}
lo += hi >> 15;
// if (p+q) overflowed, ignore the overflow and increment (p+q)
if (lo > m) {
lo &= m;
++lo;
}
return (_rand_seed = lo);
}
// The INITIALIZED state is distinguished from the SUSPENDED state because the
// conditions in which a thread is first started are different from those in which
// a suspension is resumed. These differences make it hard for us to apply the
// tougher checks when starting threads that we want to do when resuming them.
// However, when start_thread is called as a result of Thread.start, on a Java
// thread, the operation is synchronized on the Java Thread object. So there
// cannot be a race to start the thread and hence for the thread to exit while
// we are working on it. Non-Java threads that start Java threads either have
// to do so in a context in which races are impossible, or should do appropriate
// locking.
void os::start_thread(Thread* thread) {
// guard suspend/resume
MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
OSThread* osthread = thread->osthread();
osthread->set_state(RUNNABLE);
pd_start_thread(thread);
}
//---------------------------------------------------------------------------
// Helper functions for fatal error handler
void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
int cols = 0;
int cols_per_line = 0;
switch (unitsize) {
case 1: cols_per_line = 16; break;
case 2: cols_per_line = 8; break;
case 4: cols_per_line = 4; break;
case 8: cols_per_line = 2; break;
default: return;
}
address p = start;
st->print(PTR_FORMAT ": ", start);
while (p < end) {
switch (unitsize) {
case 1: st->print("%02x", *(u1*)p); break;
case 2: st->print("%04x", *(u2*)p); break;
case 4: st->print("%08x", *(u4*)p); break;
case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
}
p += unitsize;
cols++;
if (cols >= cols_per_line && p < end) {
cols = 0;
st->cr();
st->print(PTR_FORMAT ": ", p);
} else {
st->print(" ");
}
}
st->cr();
}
void os::print_environment_variables(outputStream* st, const char** env_list,
char* buffer, int len) {
if (env_list) {
st->print_cr("Environment Variables:");
for (int i = 0; env_list[i] != NULL; i++) {
if (getenv(env_list[i], buffer, len)) {
st->print(env_list[i]);
st->print("=");
st->print_cr(buffer);
}
}
}
}
void os::print_cpu_info(outputStream* st) {
// cpu
st->print("CPU:");
st->print("total %d", os::processor_count());
// It's not safe to query number of active processors after crash
// st->print("(active %d)", os::active_processor_count());
st->print(" %s", VM_Version::cpu_features());
st->cr();
pd_print_cpu_info(st);
}
void os::print_date_and_time(outputStream *st) {
time_t tloc;
(void)time(&tloc);
st->print("time: %s", ctime(&tloc)); // ctime adds newline.
double t = os::elapsedTime();
// NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
// Linux. Must be a bug in glibc ? Workaround is to round "t" to int
// before printf. We lost some precision, but who cares?
st->print_cr("elapsed time: %d seconds", (int)t);
}
// moved from debug.cpp (used to be find()) but still called from there
// The verbose parameter is only set by the debug code in one case
void os::print_location(outputStream* st, intptr_t x, bool verbose) {
address addr = (address)x;
CodeBlob* b = CodeCache::find_blob_unsafe(addr);
if (b != NULL) {
if (b->is_buffer_blob()) {
// the interpreter is generated into a buffer blob
InterpreterCodelet* i = Interpreter::codelet_containing(addr);
if (i != NULL) {
st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
i->print_on(st);
return;
}
if (Interpreter::contains(addr)) {
st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
" (not bytecode specific)", addr);
return;
}
//
if (AdapterHandlerLibrary::contains(b)) {
st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
AdapterHandlerLibrary::print_handler_on(st, b);
}
// the stubroutines are generated into a buffer blob
StubCodeDesc* d = StubCodeDesc::desc_for(addr);
if (d != NULL) {
st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
d->print_on(st);
st->cr();
return;
}
if (StubRoutines::contains(addr)) {
st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
"stub routine", addr);
return;
}
// the InlineCacheBuffer is using stubs generated into a buffer blob
if (InlineCacheBuffer::contains(addr)) {
st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
return;
}
VtableStub* v = VtableStubs::stub_containing(addr);
if (v != NULL) {
st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
v->print_on(st);
st->cr();
return;
}
}
nmethod* nm = b->as_nmethod_or_null();
if (nm != NULL) {
ResourceMark rm;
st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
addr, (int)(addr - nm->entry_point()), nm);
if (verbose) {
st->print(" for ");
nm->method()->print_value_on(st);
}
st->cr();
nm->print_nmethod(verbose);
return;
}
st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
b->print_on(st);
return;
}
if (Universe::heap()->is_in(addr)) {
HeapWord* p = Universe::heap()->block_start(addr);
bool print = false;
// If we couldn't find it it just may mean that heap wasn't parseable
// See if we were just given an oop directly
if (p != NULL && Universe::heap()->block_is_obj(p)) {
print = true;
} else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
p = (HeapWord*) addr;
print = true;
}
if (print) {
if (p == (HeapWord*) addr) {
st->print_cr(INTPTR_FORMAT " is an oop", addr);
} else {
st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
}
oop(p)->print_on(st);
return;
}
} else {
if (Universe::heap()->is_in_reserved(addr)) {
st->print_cr(INTPTR_FORMAT " is an unallocated location "
"in the heap", addr);
return;
}
}
if (JNIHandles::is_global_handle((jobject) addr)) {
st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
return;
}
if (JNIHandles::is_weak_global_handle((jobject) addr)) {
st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
return;
}
#ifndef PRODUCT
// we don't keep the block list in product mode
if (JNIHandleBlock::any_contains((jobject) addr)) {
st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
return;
}
#endif
for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
// Check for privilege stack
if (thread->privileged_stack_top() != NULL &&
thread->privileged_stack_top()->contains(addr)) {
st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
"for thread: " INTPTR_FORMAT, addr, thread);
if (verbose) thread->print_on(st);
return;
}
// If the addr is a java thread print information about that.
if (addr == (address)thread) {
if (verbose) {
thread->print_on(st);
} else {
st->print_cr(INTPTR_FORMAT " is a thread", addr);
}
return;
}
// If the addr is in the stack region for this thread then report that
// and print thread info
if (thread->stack_base() >= addr &&
addr > (thread->stack_base() - thread->stack_size())) {
st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
INTPTR_FORMAT, addr, thread);
if (verbose) thread->print_on(st);
return;
}
}
#ifndef PRODUCT
// Check if in metaspace.
if (ClassLoaderDataGraph::contains((address)addr)) {
// Use addr->print() from the debugger instead (not here)
st->print_cr(INTPTR_FORMAT
" is pointing into metadata", addr);
return;
}
#endif
// Try an OS specific find
if (os::find(addr, st)) {
return;
}
st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
}
// Looks like all platforms except IA64 can use the same function to check
// if C stack is walkable beyond current frame. The check for fp() is not
// necessary on Sparc, but it's harmless.
bool os::is_first_C_frame(frame* fr) {
#if defined(IA64) && !defined(_WIN32)
// On IA64 we have to check if the callers bsp is still valid
// (i.e. within the register stack bounds).
// Notice: this only works for threads created by the VM and only if
// we walk the current stack!!! If we want to be able to walk
// arbitrary other threads, we'll have to somehow store the thread
// object in the frame.
Thread *thread = Thread::current();
if ((address)fr->fp() <=
thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
// This check is a little hacky, because on Linux the first C
// frame's ('start_thread') register stack frame starts at
// "register_stack_base + 0x48" while on HPUX, the first C frame's
// ('__pthread_bound_body') register stack frame seems to really
// start at "register_stack_base".
return true;
} else {
return false;
}
#elif defined(IA64) && defined(_WIN32)
return true;
#else
// Load up sp, fp, sender sp and sender fp, check for reasonable values.
// Check usp first, because if that's bad the other accessors may fault
// on some architectures. Ditto ufp second, etc.
uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
// sp on amd can be 32 bit aligned.
uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
uintptr_t usp = (uintptr_t)fr->sp();
if ((usp & sp_align_mask) != 0) return true;
uintptr_t ufp = (uintptr_t)fr->fp();
if ((ufp & fp_align_mask) != 0) return true;
uintptr_t old_sp = (uintptr_t)fr->sender_sp();
if ((old_sp & sp_align_mask) != 0) return true;
if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
uintptr_t old_fp = (uintptr_t)fr->link();
if ((old_fp & fp_align_mask) != 0) return true;
if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
// stack grows downwards; if old_fp is below current fp or if the stack
// frame is too large, either the stack is corrupted or fp is not saved
// on stack (i.e. on x86, ebp may be used as general register). The stack
// is not walkable beyond current frame.
if (old_fp < ufp) return true;
if (old_fp - ufp > 64 * K) return true;
return false;
#endif
}
#ifdef ASSERT
extern "C" void test_random() {
const double m = 2147483647;
double mean = 0.0, variance = 0.0, t;
long reps = 10000;
unsigned long seed = 1;
tty->print_cr("seed %ld for %ld repeats...", seed, reps);
os::init_random(seed);
long num;
for (int k = 0; k < reps; k++) {
num = os::random();
double u = (double)num / m;
assert(u >= 0.0 && u <= 1.0, "bad random number!");
// calculate mean and variance of the random sequence
mean += u;
variance += (u*u);
}
mean /= reps;
variance /= (reps - 1);
assert(num == 1043618065, "bad seed");
tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
const double eps = 0.0001;
t = fabsd(mean - 0.5018);
assert(t < eps, "bad mean");
t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
assert(t < eps, "bad variance");
}
#endif
// Set up the boot classpath.
char* os::format_boot_path(const char* format_string,
const char* home,
int home_len,
char fileSep,
char pathSep) {
assert((fileSep == '/' && pathSep == ':') ||
(fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
// Scan the format string to determine the length of the actual
// boot classpath, and handle platform dependencies as well.
int formatted_path_len = 0;
const char* p;
for (p = format_string; *p != 0; ++p) {
if (*p == '%') formatted_path_len += home_len - 1;
++formatted_path_len;
}
char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
if (formatted_path == NULL) {
return NULL;
}
// Create boot classpath from format, substituting separator chars and
// java home directory.
char* q = formatted_path;
for (p = format_string; *p != 0; ++p) {
switch (*p) {
case '%':
strcpy(q, home);
q += home_len;
break;
case '/':
*q++ = fileSep;
break;
case ':':
*q++ = pathSep;
break;
default:
*q++ = *p;
}
}
*q = '\0';
assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
return formatted_path;
}
bool os::set_boot_path(char fileSep, char pathSep) {
const char* home = Arguments::get_java_home();
int home_len = (int)strlen(home);
static const char* meta_index_dir_format = "%/lib/";
static const char* meta_index_format = "%/lib/meta-index";
char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
if (meta_index == NULL) return false;
char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
if (meta_index_dir == NULL) return false;
Arguments::set_meta_index_path(meta_index, meta_index_dir);
// Any modification to the JAR-file list, for the boot classpath must be
// aligned with install/install/make/common/Pack.gmk. Note: boot class
// path class JARs, are stripped for StackMapTable to reduce download size.
static const char classpath_format[] =
"%/lib/resources.jar:"
"%/lib/rt.jar:"
"%/lib/sunrsasign.jar:"
"%/lib/jsse.jar:"
"%/lib/jce.jar:"
"%/lib/charsets.jar:"
"%/lib/jfr.jar:"
"%/classes";
char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
if (sysclasspath == NULL) return false;
Arguments::set_sysclasspath(sysclasspath);
return true;
}
/*
* Splits a path, based on its separator, the number of
* elements is returned back in n.
* It is the callers responsibility to:
* a> check the value of n, and n may be 0.
* b> ignore any empty path elements
* c> free up the data.
*/
char** os::split_path(const char* path, int* n) {
*n = 0;
if (path == NULL || strlen(path) == 0) {
return NULL;
}
const char psepchar = *os::path_separator();
char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
if (inpath == NULL) {
return NULL;
}
strcpy(inpath, path);
int count = 1;
char* p = strchr(inpath, psepchar);
// Get a count of elements to allocate memory
while (p != NULL) {
count++;
p++;
p = strchr(p, psepchar);
}
char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
if (opath == NULL) {
return NULL;
}
// do the actual splitting
p = inpath;
for (int i = 0 ; i < count ; i++) {
size_t len = strcspn(p, os::path_separator());
if (len > JVM_MAXPATHLEN) {
return NULL;
}
// allocate the string and add terminator storage
char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
if (s == NULL) {
return NULL;
}
strncpy(s, p, len);
s[len] = '\0';
opath[i] = s;
p += len + 1;
}
FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
*n = count;
return opath;
}
void os::set_memory_serialize_page(address page) {
int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
_mem_serialize_page = (volatile int32_t *)page;
// We initialize the serialization page shift count here
// We assume a cache line size of 64 bytes
assert(SerializePageShiftCount == count,
"thread size changed, fix SerializePageShiftCount constant");
set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
}
static volatile intptr_t SerializePageLock = 0;
// This method is called from signal handler when SIGSEGV occurs while the current
// thread tries to store to the "read-only" memory serialize page during state
// transition.
void os::block_on_serialize_page_trap() {
if (TraceSafepoint) {
tty->print_cr("Block until the serialize page permission restored");
}
// When VMThread is holding the SerializePageLock during modifying the
// access permission of the memory serialize page, the following call
// will block until the permission of that page is restored to rw.
// Generally, it is unsafe to manipulate locks in signal handlers, but in
// this case, it's OK as the signal is synchronous and we know precisely when
// it can occur.
Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
Thread::muxRelease(&SerializePageLock);
}
// Serialize all thread state variables
void os::serialize_thread_states() {
// On some platforms such as Solaris & Linux, the time duration of the page
// permission restoration is observed to be much longer than expected due to
// scheduler starvation problem etc. To avoid the long synchronization
// time and expensive page trap spinning, 'SerializePageLock' is used to block
// the mutator thread if such case is encountered. See bug 6546278 for details.
Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
os::protect_memory((char *)os::get_memory_serialize_page(),
os::vm_page_size(), MEM_PROT_READ);
os::protect_memory((char *)os::get_memory_serialize_page(),
os::vm_page_size(), MEM_PROT_RW);
Thread::muxRelease(&SerializePageLock);
}
// Returns true if the current stack pointer is above the stack shadow
// pages, false otherwise.
bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
address sp = current_stack_pointer();
// Check if we have StackShadowPages above the yellow zone. This parameter
// is dependent on the depth of the maximum VM call stack possible from
// the handler for stack overflow. 'instanceof' in the stack overflow
// handler or a println uses at least 8k stack of VM and native code
// respectively.
const int framesize_in_bytes =
Interpreter::size_top_interpreter_activation(method()) * wordSize;
int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
* vm_page_size()) + framesize_in_bytes;
// The very lower end of the stack
address stack_limit = thread->stack_base() - thread->stack_size();
return (sp > (stack_limit + reserved_area));
}
size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
uint min_pages)
{
assert(min_pages > 0, "sanity");
if (UseLargePages) {
const size_t max_page_size = region_max_size / min_pages;
for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
const size_t sz = _page_sizes[i];
const size_t mask = sz - 1;
if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
// The largest page size with no fragmentation.
return sz;
}
if (sz <= max_page_size) {
// The largest page size that satisfies the min_pages requirement.
return sz;
}
}
}
return vm_page_size();
}
#ifndef PRODUCT
void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
{
if (TracePageSizes) {
tty->print("%s: ", str);
for (int i = 0; i < count; ++i) {
tty->print(" " SIZE_FORMAT, page_sizes[i]);
}
tty->cr();
}
}
void os::trace_page_sizes(const char* str, const size_t region_min_size,
const size_t region_max_size, const size_t page_size,
const char* base, const size_t size)
{
if (TracePageSizes) {
tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
" pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
" size=" SIZE_FORMAT,
str, region_min_size, region_max_size,
page_size, base, size);
}
}
#endif // #ifndef PRODUCT
// This is the working definition of a server class machine:
// >= 2 physical CPU's and >=2GB of memory, with some fuzz
// because the graphics memory (?) sometimes masks physical memory.
// If you want to change the definition of a server class machine
// on some OS or platform, e.g., >=4GB on Windohs platforms,
// then you'll have to parameterize this method based on that state,
// as was done for logical processors here, or replicate and
// specialize this method for each platform. (Or fix os to have
// some inheritance structure and use subclassing. Sigh.)
// If you want some platform to always or never behave as a server
// class machine, change the setting of AlwaysActAsServerClassMachine
// and NeverActAsServerClassMachine in globals*.hpp.
bool os::is_server_class_machine() {
// First check for the early returns
if (NeverActAsServerClassMachine) {
return false;
}
if (AlwaysActAsServerClassMachine) {
return true;
}
// Then actually look at the machine
bool result = false;
const unsigned int server_processors = 2;
const julong server_memory = 2UL * G;
// We seem not to get our full complement of memory.
// We allow some part (1/8?) of the memory to be "missing",
// based on the sizes of DIMMs, and maybe graphics cards.
const julong missing_memory = 256UL * M;
/* Is this a server class machine? */
if ((os::active_processor_count() >= (int)server_processors) &&
(os::physical_memory() >= (server_memory - missing_memory))) {
const unsigned int logical_processors =
VM_Version::logical_processors_per_package();
if (logical_processors > 1) {
const unsigned int physical_packages =
os::active_processor_count() / logical_processors;
if (physical_packages > server_processors) {
result = true;
}
} else {
result = true;
}
}
return result;
}
void os::SuspendedThreadTask::run() {
assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
internal_do_task();
_done = true;
}
bool os::create_stack_guard_pages(char* addr, size_t bytes) {
return os::pd_create_stack_guard_pages(addr, bytes);
}
char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
char* result = pd_reserve_memory(bytes, addr, alignment_hint);
if (result != NULL) {
MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
}
return result;
}
char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
MEMFLAGS flags) {
char* result = pd_reserve_memory(bytes, addr, alignment_hint);
if (result != NULL) {
MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
MemTracker::record_virtual_memory_type((address)result, flags);
}
return result;
}
char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
char* result = pd_attempt_reserve_memory_at(bytes, addr);
if (result != NULL) {
MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
}
return result;
}
void os::split_reserved_memory(char *base, size_t size,
size_t split, bool realloc) {
pd_split_reserved_memory(base, size, split, realloc);
}
bool os::commit_memory(char* addr, size_t bytes, bool executable) {
bool res = pd_commit_memory(addr, bytes, executable);
if (res) {
MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
}
return res;
}
bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
bool executable) {
bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
if (res) {
MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
}
return res;
}
void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
const char* mesg) {
pd_commit_memory_or_exit(addr, bytes, executable, mesg);
MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
}
void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
bool executable, const char* mesg) {
os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
}
bool os::uncommit_memory(char* addr, size_t bytes) {
MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
bool res = pd_uncommit_memory(addr, bytes);
if (res) {
tkr.record((address)addr, bytes);
} else {
tkr.discard();
}
return res;
}
bool os::release_memory(char* addr, size_t bytes) {
MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
bool res = pd_release_memory(addr, bytes);
if (res) {
tkr.record((address)addr, bytes);
} else {
tkr.discard();
}
return res;
}
char* os::map_memory(int fd, const char* file_name, size_t file_offset,
char *addr, size_t bytes, bool read_only,
bool allow_exec) {
char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
if (result != NULL) {
MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
}
return result;
}
char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
char *addr, size_t bytes, bool read_only,
bool allow_exec) {
return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
read_only, allow_exec);
}
bool os::unmap_memory(char *addr, size_t bytes) {
MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
bool result = pd_unmap_memory(addr, bytes);
if (result) {
tkr.record((address)addr, bytes);
} else {
tkr.discard();
}
return result;
}
void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
pd_free_memory(addr, bytes, alignment_hint);
}
void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
pd_realign_memory(addr, bytes, alignment_hint);
}
#ifndef TARGET_OS_FAMILY_windows
/* try to switch state from state "from" to state "to"
* returns the state set after the method is complete
*/
os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
os::SuspendResume::State to)
{
os::SuspendResume::State result =
(os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
if (result == from) {
// success
return to;
}
return result;
}
#endif
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