Mon, 30 Jun 2008 17:04:59 -0700
6618726: Introduce -XX:+UnlockExperimentalVMOptions flag
Summary: experimental() flags will protect features of an experimental nature that are not supported in the regular product build. Made UseG1GC an experimental flag.
Reviewed-by: jmasa, kamg, coleenp
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2001-2006 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | # include "incls/_precompiled.incl" |
duke@435 | 26 | # include "incls/_perfMemory.cpp.incl" |
duke@435 | 27 | |
duke@435 | 28 | char* PerfMemory::_start = NULL; |
duke@435 | 29 | char* PerfMemory::_end = NULL; |
duke@435 | 30 | char* PerfMemory::_top = NULL; |
duke@435 | 31 | size_t PerfMemory::_capacity = 0; |
duke@435 | 32 | jint PerfMemory::_initialized = false; |
duke@435 | 33 | PerfDataPrologue* PerfMemory::_prologue = NULL; |
duke@435 | 34 | |
duke@435 | 35 | void perfMemory_init() { |
duke@435 | 36 | |
duke@435 | 37 | if (!UsePerfData) return; |
duke@435 | 38 | |
duke@435 | 39 | PerfMemory::initialize(); |
duke@435 | 40 | } |
duke@435 | 41 | |
duke@435 | 42 | void perfMemory_exit() { |
duke@435 | 43 | |
duke@435 | 44 | if (!UsePerfData) return; |
duke@435 | 45 | if (!PerfMemory::is_initialized()) return; |
duke@435 | 46 | |
duke@435 | 47 | // if the StatSampler is active, then we don't want to remove |
duke@435 | 48 | // resources it may be dependent on. Typically, the StatSampler |
duke@435 | 49 | // is disengaged from the watcher thread when this method is called, |
duke@435 | 50 | // but it is not disengaged if this method is invoked during a |
duke@435 | 51 | // VM abort. |
duke@435 | 52 | // |
duke@435 | 53 | if (!StatSampler::is_active()) |
duke@435 | 54 | PerfDataManager::destroy(); |
duke@435 | 55 | |
duke@435 | 56 | // remove the persistent external resources, if any. this method |
duke@435 | 57 | // does not unmap or invalidate any virtual memory allocated during |
duke@435 | 58 | // initialization. |
duke@435 | 59 | // |
duke@435 | 60 | PerfMemory::destroy(); |
duke@435 | 61 | } |
duke@435 | 62 | |
duke@435 | 63 | void PerfMemory::initialize() { |
duke@435 | 64 | |
duke@435 | 65 | if (_prologue != NULL) |
duke@435 | 66 | // initialization already performed |
duke@435 | 67 | return; |
duke@435 | 68 | |
duke@435 | 69 | size_t capacity = align_size_up(PerfDataMemorySize, |
duke@435 | 70 | os::vm_allocation_granularity()); |
duke@435 | 71 | |
duke@435 | 72 | if (PerfTraceMemOps) { |
duke@435 | 73 | tty->print("PerfDataMemorySize = " SIZE_FORMAT "," |
duke@435 | 74 | " os::vm_allocation_granularity = " SIZE_FORMAT "," |
duke@435 | 75 | " adjusted size = " SIZE_FORMAT "\n", |
duke@435 | 76 | PerfDataMemorySize, |
duke@435 | 77 | os::vm_allocation_granularity(), |
duke@435 | 78 | capacity); |
duke@435 | 79 | } |
duke@435 | 80 | |
duke@435 | 81 | // allocate PerfData memory region |
duke@435 | 82 | create_memory_region(capacity); |
duke@435 | 83 | |
duke@435 | 84 | if (_start == NULL) { |
duke@435 | 85 | |
duke@435 | 86 | // the PerfMemory region could not be created as desired. Rather |
duke@435 | 87 | // than terminating the JVM, we revert to creating the instrumentation |
duke@435 | 88 | // on the C heap. When running in this mode, external monitoring |
duke@435 | 89 | // clients cannot attach to and monitor this JVM. |
duke@435 | 90 | // |
duke@435 | 91 | // the warning is issued only in debug mode in order to avoid |
duke@435 | 92 | // additional output to the stdout or stderr output streams. |
duke@435 | 93 | // |
duke@435 | 94 | if (PrintMiscellaneous && Verbose) { |
duke@435 | 95 | warning("Could not create PerfData Memory region, reverting to malloc"); |
duke@435 | 96 | } |
duke@435 | 97 | |
duke@435 | 98 | _prologue = NEW_C_HEAP_OBJ(PerfDataPrologue); |
duke@435 | 99 | } |
duke@435 | 100 | else { |
duke@435 | 101 | |
duke@435 | 102 | // the PerfMemory region was created as expected. |
duke@435 | 103 | |
duke@435 | 104 | if (PerfTraceMemOps) { |
duke@435 | 105 | tty->print("PerfMemory created: address = " INTPTR_FORMAT "," |
duke@435 | 106 | " size = " SIZE_FORMAT "\n", |
duke@435 | 107 | (void*)_start, |
duke@435 | 108 | _capacity); |
duke@435 | 109 | } |
duke@435 | 110 | |
duke@435 | 111 | _prologue = (PerfDataPrologue *)_start; |
duke@435 | 112 | _end = _start + _capacity; |
duke@435 | 113 | _top = _start + sizeof(PerfDataPrologue); |
duke@435 | 114 | } |
duke@435 | 115 | |
duke@435 | 116 | assert(_prologue != NULL, "prologue pointer must be initialized"); |
duke@435 | 117 | |
duke@435 | 118 | #ifdef VM_LITTLE_ENDIAN |
duke@435 | 119 | _prologue->magic = (jint)0xc0c0feca; |
duke@435 | 120 | _prologue->byte_order = PERFDATA_LITTLE_ENDIAN; |
duke@435 | 121 | #else |
duke@435 | 122 | _prologue->magic = (jint)0xcafec0c0; |
duke@435 | 123 | _prologue->byte_order = PERFDATA_BIG_ENDIAN; |
duke@435 | 124 | #endif |
duke@435 | 125 | |
duke@435 | 126 | _prologue->major_version = PERFDATA_MAJOR_VERSION; |
duke@435 | 127 | _prologue->minor_version = PERFDATA_MINOR_VERSION; |
duke@435 | 128 | _prologue->accessible = 0; |
duke@435 | 129 | |
duke@435 | 130 | _prologue->entry_offset = sizeof(PerfDataPrologue); |
duke@435 | 131 | _prologue->num_entries = 0; |
duke@435 | 132 | _prologue->used = 0; |
duke@435 | 133 | _prologue->overflow = 0; |
duke@435 | 134 | _prologue->mod_time_stamp = 0; |
duke@435 | 135 | |
duke@435 | 136 | OrderAccess::release_store(&_initialized, 1); |
duke@435 | 137 | } |
duke@435 | 138 | |
duke@435 | 139 | void PerfMemory::destroy() { |
duke@435 | 140 | |
duke@435 | 141 | assert(_prologue != NULL, "prologue pointer must be initialized"); |
duke@435 | 142 | |
duke@435 | 143 | if (_start != NULL && _prologue->overflow != 0) { |
duke@435 | 144 | |
duke@435 | 145 | // This state indicates that the contiguous memory region exists and |
duke@435 | 146 | // that it wasn't large enough to hold all the counters. In this case, |
duke@435 | 147 | // we output a warning message to the user on exit if the -XX:+Verbose |
duke@435 | 148 | // flag is set (a debug only flag). External monitoring tools can detect |
duke@435 | 149 | // this condition by monitoring the _prologue->overflow word. |
duke@435 | 150 | // |
duke@435 | 151 | // There are two tunables that can help resolve this issue: |
duke@435 | 152 | // - increase the size of the PerfMemory with -XX:PerfDataMemorySize=<n> |
duke@435 | 153 | // - decrease the maximum string constant length with |
duke@435 | 154 | // -XX:PerfMaxStringConstLength=<n> |
duke@435 | 155 | // |
duke@435 | 156 | if (PrintMiscellaneous && Verbose) { |
duke@435 | 157 | warning("PerfMemory Overflow Occurred.\n" |
duke@435 | 158 | "\tCapacity = " SIZE_FORMAT " bytes" |
duke@435 | 159 | " Used = " SIZE_FORMAT " bytes" |
duke@435 | 160 | " Overflow = " INT32_FORMAT " bytes" |
duke@435 | 161 | "\n\tUse -XX:PerfDataMemorySize=<size> to specify larger size.", |
duke@435 | 162 | PerfMemory::capacity(), |
duke@435 | 163 | PerfMemory::used(), |
duke@435 | 164 | _prologue->overflow); |
duke@435 | 165 | } |
duke@435 | 166 | } |
duke@435 | 167 | |
duke@435 | 168 | if (_start != NULL) { |
duke@435 | 169 | |
duke@435 | 170 | // this state indicates that the contiguous memory region was successfully |
duke@435 | 171 | // and that persistent resources may need to be cleaned up. This is |
duke@435 | 172 | // expected to be the typical condition. |
duke@435 | 173 | // |
duke@435 | 174 | delete_memory_region(); |
duke@435 | 175 | } |
duke@435 | 176 | |
duke@435 | 177 | _start = NULL; |
duke@435 | 178 | _end = NULL; |
duke@435 | 179 | _top = NULL; |
duke@435 | 180 | _prologue = NULL; |
duke@435 | 181 | _capacity = 0; |
duke@435 | 182 | } |
duke@435 | 183 | |
duke@435 | 184 | // allocate an aligned block of memory from the PerfData memory |
duke@435 | 185 | // region. This method assumes that the PerfData memory region |
duke@435 | 186 | // was aligned on a double word boundary when created. |
duke@435 | 187 | // |
duke@435 | 188 | char* PerfMemory::alloc(size_t size) { |
duke@435 | 189 | |
duke@435 | 190 | if (!UsePerfData) return NULL; |
duke@435 | 191 | |
duke@435 | 192 | MutexLocker ml(PerfDataMemAlloc_lock); |
duke@435 | 193 | |
duke@435 | 194 | assert(_prologue != NULL, "called before initialization"); |
duke@435 | 195 | |
duke@435 | 196 | // check that there is enough memory for this request |
duke@435 | 197 | if ((_top + size) >= _end) { |
duke@435 | 198 | |
duke@435 | 199 | _prologue->overflow += (jint)size; |
duke@435 | 200 | |
duke@435 | 201 | return NULL; |
duke@435 | 202 | } |
duke@435 | 203 | |
duke@435 | 204 | char* result = _top; |
duke@435 | 205 | |
duke@435 | 206 | _top += size; |
duke@435 | 207 | |
duke@435 | 208 | assert(contains(result), "PerfData memory pointer out of range"); |
duke@435 | 209 | |
duke@435 | 210 | _prologue->used = (jint)used(); |
duke@435 | 211 | _prologue->num_entries = _prologue->num_entries + 1; |
duke@435 | 212 | |
duke@435 | 213 | return result; |
duke@435 | 214 | } |
duke@435 | 215 | |
duke@435 | 216 | void PerfMemory::mark_updated() { |
duke@435 | 217 | if (!UsePerfData) return; |
duke@435 | 218 | |
duke@435 | 219 | _prologue->mod_time_stamp = os::elapsed_counter(); |
duke@435 | 220 | } |
duke@435 | 221 | |
duke@435 | 222 | // Returns the complete path including the file name of performance data file. |
duke@435 | 223 | // Caller is expected to release the allocated memory. |
duke@435 | 224 | char* PerfMemory::get_perfdata_file_path() { |
duke@435 | 225 | char* dest_file = NULL; |
duke@435 | 226 | |
duke@435 | 227 | if (PerfDataSaveFile != NULL) { |
duke@435 | 228 | // dest_file_name stores the validated file name if file_name |
duke@435 | 229 | // contains %p which will be replaced by pid. |
duke@435 | 230 | dest_file = NEW_C_HEAP_ARRAY(char, JVM_MAXPATHLEN); |
duke@435 | 231 | if(!Arguments::copy_expand_pid(PerfDataSaveFile, strlen(PerfDataSaveFile), |
duke@435 | 232 | dest_file, JVM_MAXPATHLEN)) { |
duke@435 | 233 | FREE_C_HEAP_ARRAY(char, dest_file); |
duke@435 | 234 | if (PrintMiscellaneous && Verbose) { |
duke@435 | 235 | warning("Invalid performance data file path name specified, "\ |
duke@435 | 236 | "fall back to a default name"); |
duke@435 | 237 | } |
duke@435 | 238 | } else { |
duke@435 | 239 | return dest_file; |
duke@435 | 240 | } |
duke@435 | 241 | } |
duke@435 | 242 | // create the name of the file for retaining the instrumentation memory. |
duke@435 | 243 | dest_file = NEW_C_HEAP_ARRAY(char, PERFDATA_FILENAME_LEN); |
duke@435 | 244 | jio_snprintf(dest_file, PERFDATA_FILENAME_LEN, |
duke@435 | 245 | "%s_%d", PERFDATA_NAME, os::current_process_id()); |
duke@435 | 246 | |
duke@435 | 247 | return dest_file; |
duke@435 | 248 | } |