duke@435: /*
duke@435:  * Copyright 2001-2006 Sun Microsystems, Inc.  All Rights Reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: # include "incls/_precompiled.incl"
duke@435: # include "incls/_perfMemory.cpp.incl"
duke@435: 
duke@435: char*                    PerfMemory::_start = NULL;
duke@435: char*                    PerfMemory::_end = NULL;
duke@435: char*                    PerfMemory::_top = NULL;
duke@435: size_t                   PerfMemory::_capacity = 0;
duke@435: jint                     PerfMemory::_initialized = false;
duke@435: PerfDataPrologue*        PerfMemory::_prologue = NULL;
duke@435: 
duke@435: void perfMemory_init() {
duke@435: 
duke@435:   if (!UsePerfData) return;
duke@435: 
duke@435:   PerfMemory::initialize();
duke@435: }
duke@435: 
duke@435: void perfMemory_exit() {
duke@435: 
duke@435:   if (!UsePerfData) return;
duke@435:   if (!PerfMemory::is_initialized()) return;
duke@435: 
duke@435:   // if the StatSampler is active, then we don't want to remove
duke@435:   // resources it may be dependent on. Typically, the StatSampler
duke@435:   // is disengaged from the watcher thread when this method is called,
duke@435:   // but it is not disengaged if this method is invoked during a
duke@435:   // VM abort.
duke@435:   //
duke@435:   if (!StatSampler::is_active())
duke@435:     PerfDataManager::destroy();
duke@435: 
duke@435:   // remove the persistent external resources, if any. this method
duke@435:   // does not unmap or invalidate any virtual memory allocated during
duke@435:   // initialization.
duke@435:   //
duke@435:   PerfMemory::destroy();
duke@435: }
duke@435: 
duke@435: void PerfMemory::initialize() {
duke@435: 
duke@435:   if (_prologue != NULL)
duke@435:     // initialization already performed
duke@435:     return;
duke@435: 
duke@435:   size_t capacity = align_size_up(PerfDataMemorySize,
duke@435:                                   os::vm_allocation_granularity());
duke@435: 
duke@435:   if (PerfTraceMemOps) {
duke@435:     tty->print("PerfDataMemorySize = " SIZE_FORMAT ","
duke@435:                " os::vm_allocation_granularity = " SIZE_FORMAT ","
duke@435:                " adjusted size = " SIZE_FORMAT "\n",
duke@435:                PerfDataMemorySize,
duke@435:                os::vm_allocation_granularity(),
duke@435:                capacity);
duke@435:   }
duke@435: 
duke@435:   // allocate PerfData memory region
duke@435:   create_memory_region(capacity);
duke@435: 
duke@435:   if (_start == NULL) {
duke@435: 
duke@435:     // the PerfMemory region could not be created as desired. Rather
duke@435:     // than terminating the JVM, we revert to creating the instrumentation
duke@435:     // on the C heap. When running in this mode, external monitoring
duke@435:     // clients cannot attach to and monitor this JVM.
duke@435:     //
duke@435:     // the warning is issued only in debug mode in order to avoid
duke@435:     // additional output to the stdout or stderr output streams.
duke@435:     //
duke@435:     if (PrintMiscellaneous && Verbose) {
duke@435:       warning("Could not create PerfData Memory region, reverting to malloc");
duke@435:     }
duke@435: 
duke@435:     _prologue = NEW_C_HEAP_OBJ(PerfDataPrologue);
duke@435:   }
duke@435:   else {
duke@435: 
duke@435:     // the PerfMemory region was created as expected.
duke@435: 
duke@435:     if (PerfTraceMemOps) {
duke@435:       tty->print("PerfMemory created: address = " INTPTR_FORMAT ","
duke@435:                  " size = " SIZE_FORMAT "\n",
duke@435:                  (void*)_start,
duke@435:                  _capacity);
duke@435:     }
duke@435: 
duke@435:     _prologue = (PerfDataPrologue *)_start;
duke@435:     _end = _start + _capacity;
duke@435:     _top = _start + sizeof(PerfDataPrologue);
duke@435:   }
duke@435: 
duke@435:   assert(_prologue != NULL, "prologue pointer must be initialized");
duke@435: 
duke@435: #ifdef VM_LITTLE_ENDIAN
duke@435:   _prologue->magic = (jint)0xc0c0feca;
duke@435:   _prologue->byte_order = PERFDATA_LITTLE_ENDIAN;
duke@435: #else
duke@435:   _prologue->magic = (jint)0xcafec0c0;
duke@435:   _prologue->byte_order = PERFDATA_BIG_ENDIAN;
duke@435: #endif
duke@435: 
duke@435:   _prologue->major_version = PERFDATA_MAJOR_VERSION;
duke@435:   _prologue->minor_version = PERFDATA_MINOR_VERSION;
duke@435:   _prologue->accessible = 0;
duke@435: 
duke@435:   _prologue->entry_offset = sizeof(PerfDataPrologue);
duke@435:   _prologue->num_entries = 0;
duke@435:   _prologue->used = 0;
duke@435:   _prologue->overflow = 0;
duke@435:   _prologue->mod_time_stamp = 0;
duke@435: 
duke@435:   OrderAccess::release_store(&_initialized, 1);
duke@435: }
duke@435: 
duke@435: void PerfMemory::destroy() {
duke@435: 
duke@435:   assert(_prologue != NULL, "prologue pointer must be initialized");
duke@435: 
duke@435:   if (_start != NULL && _prologue->overflow != 0) {
duke@435: 
duke@435:     // This state indicates that the contiguous memory region exists and
duke@435:     // that it wasn't large enough to hold all the counters. In this case,
duke@435:     // we output a warning message to the user on exit if the -XX:+Verbose
duke@435:     // flag is set (a debug only flag). External monitoring tools can detect
duke@435:     // this condition by monitoring the _prologue->overflow word.
duke@435:     //
duke@435:     // There are two tunables that can help resolve this issue:
duke@435:     //   - increase the size of the PerfMemory with -XX:PerfDataMemorySize=<n>
duke@435:     //   - decrease the maximum string constant length with
duke@435:     //     -XX:PerfMaxStringConstLength=<n>
duke@435:     //
duke@435:     if (PrintMiscellaneous && Verbose) {
duke@435:       warning("PerfMemory Overflow Occurred.\n"
duke@435:               "\tCapacity = " SIZE_FORMAT " bytes"
duke@435:               "  Used = " SIZE_FORMAT " bytes"
duke@435:               "  Overflow = " INT32_FORMAT " bytes"
duke@435:               "\n\tUse -XX:PerfDataMemorySize=<size> to specify larger size.",
duke@435:               PerfMemory::capacity(),
duke@435:               PerfMemory::used(),
duke@435:               _prologue->overflow);
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   if (_start != NULL) {
duke@435: 
duke@435:     // this state indicates that the contiguous memory region was successfully
duke@435:     // and that persistent resources may need to be cleaned up. This is
duke@435:     // expected to be the typical condition.
duke@435:     //
duke@435:     delete_memory_region();
duke@435:   }
duke@435: 
duke@435:   _start = NULL;
duke@435:   _end = NULL;
duke@435:   _top = NULL;
duke@435:   _prologue = NULL;
duke@435:   _capacity = 0;
duke@435: }
duke@435: 
duke@435: // allocate an aligned block of memory from the PerfData memory
duke@435: // region. This method assumes that the PerfData memory region
duke@435: // was aligned on a double word boundary when created.
duke@435: //
duke@435: char* PerfMemory::alloc(size_t size) {
duke@435: 
duke@435:   if (!UsePerfData) return NULL;
duke@435: 
duke@435:   MutexLocker ml(PerfDataMemAlloc_lock);
duke@435: 
duke@435:   assert(_prologue != NULL, "called before initialization");
duke@435: 
duke@435:   // check that there is enough memory for this request
duke@435:   if ((_top + size) >= _end) {
duke@435: 
duke@435:     _prologue->overflow += (jint)size;
duke@435: 
duke@435:     return NULL;
duke@435:   }
duke@435: 
duke@435:   char* result = _top;
duke@435: 
duke@435:   _top += size;
duke@435: 
duke@435:   assert(contains(result), "PerfData memory pointer out of range");
duke@435: 
duke@435:   _prologue->used = (jint)used();
duke@435:   _prologue->num_entries = _prologue->num_entries + 1;
duke@435: 
duke@435:   return result;
duke@435: }
duke@435: 
duke@435: void PerfMemory::mark_updated() {
duke@435:   if (!UsePerfData) return;
duke@435: 
duke@435:   _prologue->mod_time_stamp = os::elapsed_counter();
duke@435: }
duke@435: 
duke@435: // Returns the complete path including the file name of performance data file.
duke@435: // Caller is expected to release the allocated memory.
duke@435: char* PerfMemory::get_perfdata_file_path() {
duke@435:   char* dest_file = NULL;
duke@435: 
duke@435:   if (PerfDataSaveFile != NULL) {
duke@435:     // dest_file_name stores the validated file name if file_name
duke@435:     // contains %p which will be replaced by pid.
duke@435:     dest_file = NEW_C_HEAP_ARRAY(char, JVM_MAXPATHLEN);
duke@435:     if(!Arguments::copy_expand_pid(PerfDataSaveFile, strlen(PerfDataSaveFile),
duke@435:                                    dest_file, JVM_MAXPATHLEN)) {
duke@435:       FREE_C_HEAP_ARRAY(char, dest_file);
duke@435:       if (PrintMiscellaneous && Verbose) {
duke@435:         warning("Invalid performance data file path name specified, "\
duke@435:                 "fall back to a default name");
duke@435:       }
duke@435:     } else {
duke@435:       return dest_file;
duke@435:     }
duke@435:   }
duke@435:   // create the name of the file for retaining the instrumentation memory.
duke@435:   dest_file = NEW_C_HEAP_ARRAY(char, PERFDATA_FILENAME_LEN);
duke@435:   jio_snprintf(dest_file, PERFDATA_FILENAME_LEN,
duke@435:                "%s_%d", PERFDATA_NAME, os::current_process_id());
duke@435: 
duke@435:   return dest_file;
duke@435: }