Mercurial > hg > graal-compiler
view src/share/vm/runtime/os.cpp @ 1438:a7a0ef3c6858
Added timing printout on VM shutdown.
author | Thomas Wuerthinger <wuerthinger@ssw.jku.at> |
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date | Mon, 25 Oct 2010 18:35:34 +0200 |
parents | 4ce7240d622c |
children | f03d0a26bf83 |
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/* * Copyright 1997-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * */ # include "incls/_precompiled.incl" # include "incls/_os.cpp.incl" # 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 int os::num_mallocs = 0; // # of calls to malloc/realloc size_t os::alloc_bytes = 0; // # of bytes allocated int os::num_frees = 0; // # of calls to free #endif // 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; } const time_t zone = timezone; // 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; } } 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; 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 */, true /* need_prologue */); VMThread::execute(&op1); } if (JvmtiExport::should_post_data_dump()) { JvmtiExport::post_data_dump(); } break; } default: { // Dispatch the signal to java HandleMark hm(THREAD); klassOop k = SystemDictionary::resolve_or_null(vmSymbolHandles::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, vmSymbolHandles::dispatch_name(), vmSymbolHandles::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::signal_init() { if (!ReduceSignalUsage) { // Setup JavaThread for processing signals EXCEPTION_MARK; klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::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, vmSymbolHandles::object_initializer_name(), vmSymbolHandles::threadgroup_string_void_signature(), thread_group, string, CHECK); KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); JavaCalls::call_special(&result, thread_group, group, vmSymbolHandles::add_method_name(), vmSymbolHandles::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. dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), "verify"); dll_load(buffer, ebuf, sizeof(ebuf)); // Load java dll 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); } } 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; } // --------------------- heap allocation utilities --------------------- char *os::strdup(const char *str) { size_t size = strlen(str); char *dup_str = (char *)malloc(size + 1); 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 ) fatal2("free: size field of object #%p was overwritten (%lu)", 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: %p (%ld bytes)", obj, size); } else { tty->print_cr("### previous object (not sure if correct): %p (%ld 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: %p (%ld bytes)", next_obj, next_size); } else { tty->print_cr("### next object (not sure if correct): %p (%ld bytes)", next_obj, next_size); } } void report_heap_error(void* memblock, void* bad, const char* where) { tty->print_cr("## nof_mallocs = %d, nof_frees = %d", os::num_mallocs, os::num_frees); tty->print_cr("## memory stomp: byte at %p %s object %p", 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 void* os::malloc(size_t size) { NOT_PRODUCT(num_mallocs++); NOT_PRODUCT(alloc_bytes += size); if (size == 0) { // return a valid pointer if size is zero // if NULL is returned the calling functions assume out of memory. size = 1; } NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap()); u_char* ptr = (u_char*)::malloc(size + space_before + space_after); #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, %lu bytes --> %p", size, memblock); breakpoint(); } debug_only(if (paranoid) verify_block(memblock)); if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc %lu bytes --> %p", size, memblock); return memblock; } void* os::realloc(void *memblock, size_t size) { NOT_PRODUCT(num_mallocs++); NOT_PRODUCT(alloc_bytes += size); #ifndef ASSERT return ::realloc(memblock, size); #else if (memblock == NULL) { return os::malloc(size); } if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { tty->print_cr("os::realloc caught %p", 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); if (PrintMalloc) tty->print_cr("os::remalloc %lu bytes, %p --> %p", 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, %lu bytes --> %p", size, ptr); breakpoint(); } free(memblock); } return ptr; #endif } void os::free(void *memblock) { NOT_PRODUCT(num_frees++); #ifdef ASSERT if (memblock == NULL) return; if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) { if (tty != NULL) tty->print_cr("os::free caught %p", memblock); breakpoint(); } verify_block(memblock); if (PrintMalloc && tty != NULL) // tty->print_cr("os::free %p", memblock); fprintf(stderr, "os::free %p\n", 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); 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; } } #endif ::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(); } 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); } // 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) { #ifdef IA64 // In order to walk native frames on Itanium, we need to access the unwind // table, which is inside ELF. We don't want to parse ELF after fatal error, // so return true for IA64. If we need to support C stack walking on IA64, // this function needs to be moved to CPU specific files, as fp() on IA64 // is register stack, which grows towards higher memory address. return true; #endif // 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; } #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); 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:" "%/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); if (inpath == NULL) { return NULL; } strncpy(inpath, path, strlen(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); 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); if (s == NULL) { return NULL; } strncpy(s, p, len); s[len] = '\0'; opath[i] = s; p += len + 1; } FREE_C_HEAP_ARRAY(char, inpath); *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 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; }