Tue, 09 Oct 2012 10:09:34 -0700
7197424: update copyright year to match last edit in jdk8 hotspot repository
Summary: Update copyright year to 2012 for relevant files
Reviewed-by: dholmes, coleenp
duke@435 | 1 | /* |
coleenp@4037 | 2 | * Copyright (c) 1997, 2012, Oracle and/or its affiliates. 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 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "code/codeCache.hpp" |
coleenp@4037 | 27 | #include "code/compiledIC.hpp" |
coleenp@4037 | 28 | #include "code/icBuffer.hpp" |
stefank@2314 | 29 | #include "code/nmethod.hpp" |
stefank@2314 | 30 | #include "compiler/compileBroker.hpp" |
stefank@2314 | 31 | #include "memory/resourceArea.hpp" |
coleenp@4037 | 32 | #include "oops/method.hpp" |
stefank@2314 | 33 | #include "runtime/atomic.hpp" |
stefank@2314 | 34 | #include "runtime/compilationPolicy.hpp" |
stefank@2314 | 35 | #include "runtime/mutexLocker.hpp" |
stefank@2314 | 36 | #include "runtime/os.hpp" |
stefank@2314 | 37 | #include "runtime/sweeper.hpp" |
stefank@2314 | 38 | #include "runtime/vm_operations.hpp" |
stefank@2314 | 39 | #include "utilities/events.hpp" |
stefank@2314 | 40 | #include "utilities/xmlstream.hpp" |
duke@435 | 41 | |
never@2916 | 42 | #ifdef ASSERT |
never@2916 | 43 | |
never@2916 | 44 | #define SWEEP(nm) record_sweep(nm, __LINE__) |
never@2916 | 45 | // Sweeper logging code |
never@2916 | 46 | class SweeperRecord { |
never@2916 | 47 | public: |
never@2916 | 48 | int traversal; |
never@2916 | 49 | int invocation; |
never@2916 | 50 | int compile_id; |
never@2916 | 51 | long traversal_mark; |
never@2916 | 52 | int state; |
never@2916 | 53 | const char* kind; |
never@2916 | 54 | address vep; |
never@2916 | 55 | address uep; |
never@2916 | 56 | int line; |
never@2916 | 57 | |
never@2916 | 58 | void print() { |
never@2916 | 59 | tty->print_cr("traversal = %d invocation = %d compile_id = %d %s uep = " PTR_FORMAT " vep = " |
never@2916 | 60 | PTR_FORMAT " state = %d traversal_mark %d line = %d", |
never@2916 | 61 | traversal, |
never@2916 | 62 | invocation, |
never@2916 | 63 | compile_id, |
never@2916 | 64 | kind == NULL ? "" : kind, |
never@2916 | 65 | uep, |
never@2916 | 66 | vep, |
never@2916 | 67 | state, |
never@2916 | 68 | traversal_mark, |
never@2916 | 69 | line); |
never@2916 | 70 | } |
never@2916 | 71 | }; |
never@2916 | 72 | |
never@2916 | 73 | static int _sweep_index = 0; |
never@2916 | 74 | static SweeperRecord* _records = NULL; |
never@2916 | 75 | |
never@2916 | 76 | void NMethodSweeper::report_events(int id, address entry) { |
never@2916 | 77 | if (_records != NULL) { |
never@2916 | 78 | for (int i = _sweep_index; i < SweeperLogEntries; i++) { |
never@2916 | 79 | if (_records[i].uep == entry || |
never@2916 | 80 | _records[i].vep == entry || |
never@2916 | 81 | _records[i].compile_id == id) { |
never@2916 | 82 | _records[i].print(); |
never@2916 | 83 | } |
never@2916 | 84 | } |
never@2916 | 85 | for (int i = 0; i < _sweep_index; i++) { |
never@2916 | 86 | if (_records[i].uep == entry || |
never@2916 | 87 | _records[i].vep == entry || |
never@2916 | 88 | _records[i].compile_id == id) { |
never@2916 | 89 | _records[i].print(); |
never@2916 | 90 | } |
never@2916 | 91 | } |
never@2916 | 92 | } |
never@2916 | 93 | } |
never@2916 | 94 | |
never@2916 | 95 | void NMethodSweeper::report_events() { |
never@2916 | 96 | if (_records != NULL) { |
never@2916 | 97 | for (int i = _sweep_index; i < SweeperLogEntries; i++) { |
never@2916 | 98 | // skip empty records |
never@2916 | 99 | if (_records[i].vep == NULL) continue; |
never@2916 | 100 | _records[i].print(); |
never@2916 | 101 | } |
never@2916 | 102 | for (int i = 0; i < _sweep_index; i++) { |
never@2916 | 103 | // skip empty records |
never@2916 | 104 | if (_records[i].vep == NULL) continue; |
never@2916 | 105 | _records[i].print(); |
never@2916 | 106 | } |
never@2916 | 107 | } |
never@2916 | 108 | } |
never@2916 | 109 | |
never@2916 | 110 | void NMethodSweeper::record_sweep(nmethod* nm, int line) { |
never@2916 | 111 | if (_records != NULL) { |
never@2916 | 112 | _records[_sweep_index].traversal = _traversals; |
never@2916 | 113 | _records[_sweep_index].traversal_mark = nm->_stack_traversal_mark; |
never@2916 | 114 | _records[_sweep_index].invocation = _invocations; |
never@2916 | 115 | _records[_sweep_index].compile_id = nm->compile_id(); |
never@2916 | 116 | _records[_sweep_index].kind = nm->compile_kind(); |
never@2916 | 117 | _records[_sweep_index].state = nm->_state; |
never@2916 | 118 | _records[_sweep_index].vep = nm->verified_entry_point(); |
never@2916 | 119 | _records[_sweep_index].uep = nm->entry_point(); |
never@2916 | 120 | _records[_sweep_index].line = line; |
never@2916 | 121 | |
never@2916 | 122 | _sweep_index = (_sweep_index + 1) % SweeperLogEntries; |
never@2916 | 123 | } |
never@2916 | 124 | } |
never@2916 | 125 | #else |
never@2916 | 126 | #define SWEEP(nm) |
never@2916 | 127 | #endif |
never@2916 | 128 | |
never@2916 | 129 | |
duke@435 | 130 | long NMethodSweeper::_traversals = 0; // No. of stack traversals performed |
never@1970 | 131 | nmethod* NMethodSweeper::_current = NULL; // Current nmethod |
never@1999 | 132 | int NMethodSweeper::_seen = 0 ; // No. of nmethods we have currently processed in current pass of CodeCache |
never@1999 | 133 | |
never@1999 | 134 | volatile int NMethodSweeper::_invocations = 0; // No. of invocations left until we are completed with this pass |
never@1999 | 135 | volatile int NMethodSweeper::_sweep_started = 0; // Whether a sweep is in progress. |
duke@435 | 136 | |
duke@435 | 137 | jint NMethodSweeper::_locked_seen = 0; |
duke@435 | 138 | jint NMethodSweeper::_not_entrant_seen_on_stack = 0; |
duke@435 | 139 | bool NMethodSweeper::_rescan = false; |
never@1893 | 140 | bool NMethodSweeper::_do_sweep = false; |
kvn@1637 | 141 | bool NMethodSweeper::_was_full = false; |
kvn@1637 | 142 | jint NMethodSweeper::_advise_to_sweep = 0; |
kvn@1637 | 143 | jlong NMethodSweeper::_last_was_full = 0; |
kvn@1637 | 144 | uint NMethodSweeper::_highest_marked = 0; |
kvn@1637 | 145 | long NMethodSweeper::_was_full_traversal = 0; |
duke@435 | 146 | |
jrose@1424 | 147 | class MarkActivationClosure: public CodeBlobClosure { |
jrose@1424 | 148 | public: |
jrose@1424 | 149 | virtual void do_code_blob(CodeBlob* cb) { |
jrose@1424 | 150 | // If we see an activation belonging to a non_entrant nmethod, we mark it. |
jrose@1424 | 151 | if (cb->is_nmethod() && ((nmethod*)cb)->is_not_entrant()) { |
jrose@1424 | 152 | ((nmethod*)cb)->mark_as_seen_on_stack(); |
jrose@1424 | 153 | } |
jrose@1424 | 154 | } |
jrose@1424 | 155 | }; |
jrose@1424 | 156 | static MarkActivationClosure mark_activation_closure; |
jrose@1424 | 157 | |
never@1893 | 158 | void NMethodSweeper::scan_stacks() { |
duke@435 | 159 | assert(SafepointSynchronize::is_at_safepoint(), "must be executed at a safepoint"); |
duke@435 | 160 | if (!MethodFlushing) return; |
never@1893 | 161 | _do_sweep = true; |
duke@435 | 162 | |
duke@435 | 163 | // No need to synchronize access, since this is always executed at a |
duke@435 | 164 | // safepoint. If we aren't in the middle of scan and a rescan |
never@1893 | 165 | // hasn't been requested then just return. If UseCodeCacheFlushing is on and |
never@1893 | 166 | // code cache flushing is in progress, don't skip sweeping to help make progress |
never@1893 | 167 | // clearing space in the code cache. |
never@1893 | 168 | if ((_current == NULL && !_rescan) && !(UseCodeCacheFlushing && !CompileBroker::should_compile_new_jobs())) { |
never@1893 | 169 | _do_sweep = false; |
never@1893 | 170 | return; |
never@1893 | 171 | } |
duke@435 | 172 | |
duke@435 | 173 | // Make sure CompiledIC_lock in unlocked, since we might update some |
duke@435 | 174 | // inline caches. If it is, we just bail-out and try later. |
duke@435 | 175 | if (CompiledIC_lock->is_locked() || Patching_lock->is_locked()) return; |
duke@435 | 176 | |
duke@435 | 177 | // Check for restart |
duke@435 | 178 | assert(CodeCache::find_blob_unsafe(_current) == _current, "Sweeper nmethod cached state invalid"); |
duke@435 | 179 | if (_current == NULL) { |
duke@435 | 180 | _seen = 0; |
duke@435 | 181 | _invocations = NmethodSweepFraction; |
never@1893 | 182 | _current = CodeCache::first_nmethod(); |
duke@435 | 183 | _traversals += 1; |
duke@435 | 184 | if (PrintMethodFlushing) { |
duke@435 | 185 | tty->print_cr("### Sweep: stack traversal %d", _traversals); |
duke@435 | 186 | } |
jrose@1424 | 187 | Threads::nmethods_do(&mark_activation_closure); |
duke@435 | 188 | |
duke@435 | 189 | // reset the flags since we started a scan from the beginning. |
duke@435 | 190 | _rescan = false; |
duke@435 | 191 | _locked_seen = 0; |
duke@435 | 192 | _not_entrant_seen_on_stack = 0; |
duke@435 | 193 | } |
duke@435 | 194 | |
kvn@1637 | 195 | if (UseCodeCacheFlushing) { |
kvn@1637 | 196 | if (!CodeCache::needs_flushing()) { |
never@1893 | 197 | // scan_stacks() runs during a safepoint, no race with setters |
kvn@1637 | 198 | _advise_to_sweep = 0; |
kvn@1637 | 199 | } |
kvn@1637 | 200 | |
kvn@1637 | 201 | if (was_full()) { |
kvn@1637 | 202 | // There was some progress so attempt to restart the compiler |
kvn@1637 | 203 | jlong now = os::javaTimeMillis(); |
kvn@1637 | 204 | jlong max_interval = (jlong)MinCodeCacheFlushingInterval * (jlong)1000; |
kvn@1637 | 205 | jlong curr_interval = now - _last_was_full; |
kvn@1637 | 206 | if ((!CodeCache::needs_flushing()) && (curr_interval > max_interval)) { |
kvn@1637 | 207 | CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation); |
kvn@1637 | 208 | set_was_full(false); |
kvn@1637 | 209 | |
kvn@1637 | 210 | // Update the _last_was_full time so we can tell how fast the |
kvn@1637 | 211 | // code cache is filling up |
kvn@1637 | 212 | _last_was_full = os::javaTimeMillis(); |
kvn@1637 | 213 | |
never@1999 | 214 | log_sweep("restart_compiler"); |
kvn@1637 | 215 | } |
kvn@1637 | 216 | } |
kvn@1637 | 217 | } |
duke@435 | 218 | } |
duke@435 | 219 | |
never@1893 | 220 | void NMethodSweeper::possibly_sweep() { |
never@1999 | 221 | assert(JavaThread::current()->thread_state() == _thread_in_vm, "must run in vm mode"); |
never@1893 | 222 | if ((!MethodFlushing) || (!_do_sweep)) return; |
never@1893 | 223 | |
never@1893 | 224 | if (_invocations > 0) { |
never@1893 | 225 | // Only one thread at a time will sweep |
never@1893 | 226 | jint old = Atomic::cmpxchg( 1, &_sweep_started, 0 ); |
never@1893 | 227 | if (old != 0) { |
never@1893 | 228 | return; |
never@1893 | 229 | } |
never@2916 | 230 | #ifdef ASSERT |
never@2916 | 231 | if (LogSweeper && _records == NULL) { |
never@2916 | 232 | // Create the ring buffer for the logging code |
zgu@3900 | 233 | _records = NEW_C_HEAP_ARRAY(SweeperRecord, SweeperLogEntries, mtGC); |
never@2916 | 234 | memset(_records, 0, sizeof(SweeperRecord) * SweeperLogEntries); |
never@2916 | 235 | } |
never@2916 | 236 | #endif |
never@1999 | 237 | if (_invocations > 0) { |
never@1999 | 238 | sweep_code_cache(); |
never@1999 | 239 | _invocations--; |
never@1999 | 240 | } |
never@1999 | 241 | _sweep_started = 0; |
never@1893 | 242 | } |
never@1893 | 243 | } |
never@1893 | 244 | |
never@1893 | 245 | void NMethodSweeper::sweep_code_cache() { |
never@1893 | 246 | #ifdef ASSERT |
never@1893 | 247 | jlong sweep_start; |
never@1999 | 248 | if (PrintMethodFlushing) { |
never@1893 | 249 | sweep_start = os::javaTimeMillis(); |
never@1893 | 250 | } |
never@1893 | 251 | #endif |
never@1893 | 252 | if (PrintMethodFlushing && Verbose) { |
never@1999 | 253 | tty->print_cr("### Sweep at %d out of %d. Invocations left: %d", _seen, CodeCache::nof_nmethods(), _invocations); |
never@1893 | 254 | } |
never@1893 | 255 | |
never@1999 | 256 | // We want to visit all nmethods after NmethodSweepFraction |
never@1999 | 257 | // invocations so divide the remaining number of nmethods by the |
never@1999 | 258 | // remaining number of invocations. This is only an estimate since |
never@1999 | 259 | // the number of nmethods changes during the sweep so the final |
never@1999 | 260 | // stage must iterate until it there are no more nmethods. |
never@1999 | 261 | int todo = (CodeCache::nof_nmethods() - _seen) / _invocations; |
never@1893 | 262 | |
never@1893 | 263 | assert(!SafepointSynchronize::is_at_safepoint(), "should not be in safepoint when we get here"); |
never@1893 | 264 | assert(!CodeCache_lock->owned_by_self(), "just checking"); |
never@1893 | 265 | |
never@1893 | 266 | { |
never@1893 | 267 | MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); |
never@1893 | 268 | |
never@1999 | 269 | // The last invocation iterates until there are no more nmethods |
never@1999 | 270 | for (int i = 0; (i < todo || _invocations == 1) && _current != NULL; i++) { |
iveresov@3572 | 271 | if (SafepointSynchronize::is_synchronizing()) { // Safepoint request |
iveresov@3572 | 272 | if (PrintMethodFlushing && Verbose) { |
iveresov@3572 | 273 | tty->print_cr("### Sweep at %d out of %d, invocation: %d, yielding to safepoint", _seen, CodeCache::nof_nmethods(), _invocations); |
iveresov@3572 | 274 | } |
iveresov@3572 | 275 | MutexUnlockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); |
never@1893 | 276 | |
iveresov@3572 | 277 | assert(Thread::current()->is_Java_thread(), "should be java thread"); |
iveresov@3572 | 278 | JavaThread* thread = (JavaThread*)Thread::current(); |
iveresov@3572 | 279 | ThreadBlockInVM tbivm(thread); |
iveresov@3572 | 280 | thread->java_suspend_self(); |
iveresov@3572 | 281 | } |
never@1999 | 282 | // Since we will give up the CodeCache_lock, always skip ahead |
never@1999 | 283 | // to the next nmethod. Other blobs can be deleted by other |
never@1999 | 284 | // threads but nmethods are only reclaimed by the sweeper. |
never@1970 | 285 | nmethod* next = CodeCache::next_nmethod(_current); |
never@1893 | 286 | |
never@1893 | 287 | // Now ready to process nmethod and give up CodeCache_lock |
never@1893 | 288 | { |
never@1893 | 289 | MutexUnlockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); |
never@1970 | 290 | process_nmethod(_current); |
never@1893 | 291 | } |
never@1893 | 292 | _seen++; |
never@1893 | 293 | _current = next; |
never@1893 | 294 | } |
never@1893 | 295 | } |
never@1893 | 296 | |
never@1999 | 297 | assert(_invocations > 1 || _current == NULL, "must have scanned the whole cache"); |
never@1999 | 298 | |
never@1893 | 299 | if (_current == NULL && !_rescan && (_locked_seen || _not_entrant_seen_on_stack)) { |
never@1893 | 300 | // we've completed a scan without making progress but there were |
never@1893 | 301 | // nmethods we were unable to process either because they were |
never@1893 | 302 | // locked or were still on stack. We don't have to aggresively |
never@1893 | 303 | // clean them up so just stop scanning. We could scan once more |
never@1893 | 304 | // but that complicates the control logic and it's unlikely to |
never@1893 | 305 | // matter much. |
never@1893 | 306 | if (PrintMethodFlushing) { |
never@1893 | 307 | tty->print_cr("### Couldn't make progress on some nmethods so stopping sweep"); |
never@1893 | 308 | } |
never@1893 | 309 | } |
never@1893 | 310 | |
never@1893 | 311 | #ifdef ASSERT |
never@1893 | 312 | if(PrintMethodFlushing) { |
never@1893 | 313 | jlong sweep_end = os::javaTimeMillis(); |
never@1893 | 314 | tty->print_cr("### sweeper: sweep time(%d): " INT64_FORMAT, _invocations, sweep_end - sweep_start); |
never@1893 | 315 | } |
never@1893 | 316 | #endif |
never@1999 | 317 | |
never@1999 | 318 | if (_invocations == 1) { |
never@1999 | 319 | log_sweep("finished"); |
never@1999 | 320 | } |
never@1893 | 321 | } |
never@1893 | 322 | |
never@2916 | 323 | class NMethodMarker: public StackObj { |
never@2916 | 324 | private: |
never@2916 | 325 | CompilerThread* _thread; |
never@2916 | 326 | public: |
never@2916 | 327 | NMethodMarker(nmethod* nm) { |
never@2916 | 328 | _thread = CompilerThread::current(); |
coleenp@4037 | 329 | if (!nm->is_zombie() && !nm->is_unloaded()) { |
coleenp@4037 | 330 | // Only expose live nmethods for scanning |
never@2916 | 331 | _thread->set_scanned_nmethod(nm); |
never@2916 | 332 | } |
coleenp@4037 | 333 | } |
never@2916 | 334 | ~NMethodMarker() { |
never@2916 | 335 | _thread->set_scanned_nmethod(NULL); |
never@2916 | 336 | } |
never@2916 | 337 | }; |
never@2916 | 338 | |
coleenp@4037 | 339 | void NMethodSweeper::release_nmethod(nmethod *nm) { |
coleenp@4037 | 340 | // Clean up any CompiledICHolders |
coleenp@4037 | 341 | { |
coleenp@4037 | 342 | ResourceMark rm; |
coleenp@4037 | 343 | MutexLocker ml_patch(CompiledIC_lock); |
coleenp@4037 | 344 | RelocIterator iter(nm); |
coleenp@4037 | 345 | while (iter.next()) { |
coleenp@4037 | 346 | if (iter.type() == relocInfo::virtual_call_type) { |
coleenp@4037 | 347 | CompiledIC::cleanup_call_site(iter.virtual_call_reloc()); |
coleenp@4037 | 348 | } |
coleenp@4037 | 349 | } |
coleenp@4037 | 350 | } |
coleenp@4037 | 351 | |
coleenp@4037 | 352 | MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); |
coleenp@4037 | 353 | nm->flush(); |
coleenp@4037 | 354 | } |
duke@435 | 355 | |
duke@435 | 356 | void NMethodSweeper::process_nmethod(nmethod *nm) { |
never@1893 | 357 | assert(!CodeCache_lock->owned_by_self(), "just checking"); |
never@1893 | 358 | |
never@2916 | 359 | // Make sure this nmethod doesn't get unloaded during the scan, |
never@2916 | 360 | // since the locks acquired below might safepoint. |
never@2916 | 361 | NMethodMarker nmm(nm); |
never@2916 | 362 | |
never@2916 | 363 | SWEEP(nm); |
never@2916 | 364 | |
duke@435 | 365 | // Skip methods that are currently referenced by the VM |
duke@435 | 366 | if (nm->is_locked_by_vm()) { |
duke@435 | 367 | // But still remember to clean-up inline caches for alive nmethods |
duke@435 | 368 | if (nm->is_alive()) { |
duke@435 | 369 | // Clean-up all inline caches that points to zombie/non-reentrant methods |
never@1893 | 370 | MutexLocker cl(CompiledIC_lock); |
duke@435 | 371 | nm->cleanup_inline_caches(); |
never@2916 | 372 | SWEEP(nm); |
duke@435 | 373 | } else { |
duke@435 | 374 | _locked_seen++; |
never@2916 | 375 | SWEEP(nm); |
duke@435 | 376 | } |
duke@435 | 377 | return; |
duke@435 | 378 | } |
duke@435 | 379 | |
duke@435 | 380 | if (nm->is_zombie()) { |
duke@435 | 381 | // If it is first time, we see nmethod then we mark it. Otherwise, |
duke@435 | 382 | // we reclame it. When we have seen a zombie method twice, we know that |
never@1999 | 383 | // there are no inline caches that refer to it. |
duke@435 | 384 | if (nm->is_marked_for_reclamation()) { |
duke@435 | 385 | assert(!nm->is_locked_by_vm(), "must not flush locked nmethods"); |
ysr@1376 | 386 | if (PrintMethodFlushing && Verbose) { |
kvn@1637 | 387 | tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (marked for reclamation) being flushed", nm->compile_id(), nm); |
ysr@1376 | 388 | } |
coleenp@4037 | 389 | release_nmethod(nm); |
duke@435 | 390 | } else { |
ysr@1376 | 391 | if (PrintMethodFlushing && Verbose) { |
kvn@1637 | 392 | tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (zombie) being marked for reclamation", nm->compile_id(), nm); |
ysr@1376 | 393 | } |
duke@435 | 394 | nm->mark_for_reclamation(); |
duke@435 | 395 | _rescan = true; |
never@2916 | 396 | SWEEP(nm); |
duke@435 | 397 | } |
duke@435 | 398 | } else if (nm->is_not_entrant()) { |
duke@435 | 399 | // If there is no current activations of this method on the |
duke@435 | 400 | // stack we can safely convert it to a zombie method |
duke@435 | 401 | if (nm->can_not_entrant_be_converted()) { |
ysr@1376 | 402 | if (PrintMethodFlushing && Verbose) { |
kvn@1637 | 403 | tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (not entrant) being made zombie", nm->compile_id(), nm); |
ysr@1376 | 404 | } |
duke@435 | 405 | nm->make_zombie(); |
duke@435 | 406 | _rescan = true; |
never@2916 | 407 | SWEEP(nm); |
duke@435 | 408 | } else { |
duke@435 | 409 | // Still alive, clean up its inline caches |
never@1893 | 410 | MutexLocker cl(CompiledIC_lock); |
duke@435 | 411 | nm->cleanup_inline_caches(); |
duke@435 | 412 | // we coudn't transition this nmethod so don't immediately |
duke@435 | 413 | // request a rescan. If this method stays on the stack for a |
never@1893 | 414 | // long time we don't want to keep rescanning the code cache. |
duke@435 | 415 | _not_entrant_seen_on_stack++; |
never@2916 | 416 | SWEEP(nm); |
duke@435 | 417 | } |
duke@435 | 418 | } else if (nm->is_unloaded()) { |
duke@435 | 419 | // Unloaded code, just make it a zombie |
ysr@1376 | 420 | if (PrintMethodFlushing && Verbose) |
kvn@1637 | 421 | tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (unloaded) being made zombie", nm->compile_id(), nm); |
ysr@1376 | 422 | if (nm->is_osr_method()) { |
coleenp@4037 | 423 | SWEEP(nm); |
duke@435 | 424 | // No inline caches will ever point to osr methods, so we can just remove it |
coleenp@4037 | 425 | release_nmethod(nm); |
duke@435 | 426 | } else { |
duke@435 | 427 | nm->make_zombie(); |
duke@435 | 428 | _rescan = true; |
never@2916 | 429 | SWEEP(nm); |
duke@435 | 430 | } |
duke@435 | 431 | } else { |
duke@435 | 432 | assert(nm->is_alive(), "should be alive"); |
kvn@1637 | 433 | |
kvn@1637 | 434 | if (UseCodeCacheFlushing) { |
kvn@1637 | 435 | if ((nm->method()->code() != nm) && !(nm->is_locked_by_vm()) && !(nm->is_osr_method()) && |
kvn@1637 | 436 | (_traversals > _was_full_traversal+2) && (((uint)nm->compile_id()) < _highest_marked) && |
kvn@1637 | 437 | CodeCache::needs_flushing()) { |
kvn@1637 | 438 | // This method has not been called since the forced cleanup happened |
kvn@1637 | 439 | nm->make_not_entrant(); |
kvn@1637 | 440 | } |
kvn@1637 | 441 | } |
kvn@1637 | 442 | |
duke@435 | 443 | // Clean-up all inline caches that points to zombie/non-reentrant methods |
never@1893 | 444 | MutexLocker cl(CompiledIC_lock); |
duke@435 | 445 | nm->cleanup_inline_caches(); |
never@2916 | 446 | SWEEP(nm); |
duke@435 | 447 | } |
duke@435 | 448 | } |
kvn@1637 | 449 | |
kvn@1637 | 450 | // Code cache unloading: when compilers notice the code cache is getting full, |
kvn@1637 | 451 | // they will call a vm op that comes here. This code attempts to speculatively |
kvn@1637 | 452 | // unload the oldest half of the nmethods (based on the compile job id) by |
kvn@1637 | 453 | // saving the old code in a list in the CodeCache. Then |
never@1893 | 454 | // execution resumes. If a method so marked is not called by the second sweeper |
never@1893 | 455 | // stack traversal after the current one, the nmethod will be marked non-entrant and |
coleenp@4037 | 456 | // got rid of by normal sweeping. If the method is called, the Method*'s |
coleenp@4037 | 457 | // _code field is restored and the Method*/nmethod |
kvn@1637 | 458 | // go back to their normal state. |
kvn@1637 | 459 | void NMethodSweeper::handle_full_code_cache(bool is_full) { |
kvn@1637 | 460 | // Only the first one to notice can advise us to start early cleaning |
kvn@1637 | 461 | if (!is_full){ |
kvn@1637 | 462 | jint old = Atomic::cmpxchg( 1, &_advise_to_sweep, 0 ); |
kvn@1637 | 463 | if (old != 0) { |
kvn@1637 | 464 | return; |
kvn@1637 | 465 | } |
kvn@1637 | 466 | } |
kvn@1637 | 467 | |
kvn@1637 | 468 | if (is_full) { |
kvn@1637 | 469 | // Since code cache is full, immediately stop new compiles |
kvn@1637 | 470 | bool did_set = CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation); |
kvn@1637 | 471 | if (!did_set) { |
kvn@1637 | 472 | // only the first to notice can start the cleaning, |
kvn@1637 | 473 | // others will go back and block |
kvn@1637 | 474 | return; |
kvn@1637 | 475 | } |
kvn@1637 | 476 | set_was_full(true); |
kvn@1637 | 477 | |
kvn@1637 | 478 | // If we run out within MinCodeCacheFlushingInterval of the last unload time, give up |
kvn@1637 | 479 | jlong now = os::javaTimeMillis(); |
kvn@1637 | 480 | jlong max_interval = (jlong)MinCodeCacheFlushingInterval * (jlong)1000; |
kvn@1637 | 481 | jlong curr_interval = now - _last_was_full; |
kvn@1637 | 482 | if (curr_interval < max_interval) { |
kvn@1637 | 483 | _rescan = true; |
never@1999 | 484 | log_sweep("disable_compiler", "flushing_interval='" UINT64_FORMAT "'", |
never@1999 | 485 | curr_interval/1000); |
kvn@1637 | 486 | return; |
kvn@1637 | 487 | } |
kvn@1637 | 488 | } |
kvn@1637 | 489 | |
kvn@1637 | 490 | VM_HandleFullCodeCache op(is_full); |
kvn@1637 | 491 | VMThread::execute(&op); |
kvn@1637 | 492 | |
kvn@1637 | 493 | // rescan again as soon as possible |
kvn@1637 | 494 | _rescan = true; |
kvn@1637 | 495 | } |
kvn@1637 | 496 | |
kvn@1637 | 497 | void NMethodSweeper::speculative_disconnect_nmethods(bool is_full) { |
kvn@1637 | 498 | // If there was a race in detecting full code cache, only run |
kvn@1637 | 499 | // one vm op for it or keep the compiler shut off |
kvn@1637 | 500 | |
kvn@1637 | 501 | debug_only(jlong start = os::javaTimeMillis();) |
kvn@1637 | 502 | |
kvn@1637 | 503 | if ((!was_full()) && (is_full)) { |
kvn@1637 | 504 | if (!CodeCache::needs_flushing()) { |
never@1999 | 505 | log_sweep("restart_compiler"); |
kvn@1637 | 506 | CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation); |
kvn@1637 | 507 | return; |
kvn@1637 | 508 | } |
kvn@1637 | 509 | } |
kvn@1637 | 510 | |
kvn@1637 | 511 | // Traverse the code cache trying to dump the oldest nmethods |
kvn@1637 | 512 | uint curr_max_comp_id = CompileBroker::get_compilation_id(); |
kvn@1637 | 513 | uint flush_target = ((curr_max_comp_id - _highest_marked) >> 1) + _highest_marked; |
never@1999 | 514 | log_sweep("start_cleaning"); |
kvn@1637 | 515 | |
kvn@1637 | 516 | nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); |
kvn@1637 | 517 | jint disconnected = 0; |
kvn@1637 | 518 | jint made_not_entrant = 0; |
kvn@1637 | 519 | while ((nm != NULL)){ |
kvn@1637 | 520 | uint curr_comp_id = nm->compile_id(); |
kvn@1637 | 521 | |
kvn@1637 | 522 | // OSR methods cannot be flushed like this. Also, don't flush native methods |
kvn@1637 | 523 | // since they are part of the JDK in most cases |
kvn@1637 | 524 | if (nm->is_in_use() && (!nm->is_osr_method()) && (!nm->is_locked_by_vm()) && |
kvn@1637 | 525 | (!nm->is_native_method()) && ((curr_comp_id < flush_target))) { |
kvn@1637 | 526 | |
kvn@1637 | 527 | if ((nm->method()->code() == nm)) { |
kvn@1637 | 528 | // This method has not been previously considered for |
kvn@1637 | 529 | // unloading or it was restored already |
kvn@1637 | 530 | CodeCache::speculatively_disconnect(nm); |
kvn@1637 | 531 | disconnected++; |
kvn@1637 | 532 | } else if (nm->is_speculatively_disconnected()) { |
kvn@1637 | 533 | // This method was previously considered for preemptive unloading and was not called since then |
iveresov@2138 | 534 | CompilationPolicy::policy()->delay_compilation(nm->method()); |
kvn@1637 | 535 | nm->make_not_entrant(); |
kvn@1637 | 536 | made_not_entrant++; |
kvn@1637 | 537 | } |
kvn@1637 | 538 | |
kvn@1637 | 539 | if (curr_comp_id > _highest_marked) { |
kvn@1637 | 540 | _highest_marked = curr_comp_id; |
kvn@1637 | 541 | } |
kvn@1637 | 542 | } |
kvn@1637 | 543 | nm = CodeCache::alive_nmethod(CodeCache::next(nm)); |
kvn@1637 | 544 | } |
kvn@1637 | 545 | |
never@1999 | 546 | log_sweep("stop_cleaning", |
never@1999 | 547 | "disconnected='" UINT32_FORMAT "' made_not_entrant='" UINT32_FORMAT "'", |
never@1999 | 548 | disconnected, made_not_entrant); |
kvn@1637 | 549 | |
never@1893 | 550 | // Shut off compiler. Sweeper will start over with a new stack scan and |
never@1893 | 551 | // traversal cycle and turn it back on if it clears enough space. |
kvn@1637 | 552 | if (was_full()) { |
kvn@1637 | 553 | _last_was_full = os::javaTimeMillis(); |
kvn@1637 | 554 | CompileBroker::set_should_compile_new_jobs(CompileBroker::stop_compilation); |
kvn@1637 | 555 | } |
kvn@1637 | 556 | |
kvn@1637 | 557 | // After two more traversals the sweeper will get rid of unrestored nmethods |
kvn@1637 | 558 | _was_full_traversal = _traversals; |
kvn@1637 | 559 | #ifdef ASSERT |
kvn@1637 | 560 | jlong end = os::javaTimeMillis(); |
kvn@1637 | 561 | if(PrintMethodFlushing && Verbose) { |
kvn@1637 | 562 | tty->print_cr("### sweeper: unload time: " INT64_FORMAT, end-start); |
kvn@1637 | 563 | } |
kvn@1637 | 564 | #endif |
kvn@1637 | 565 | } |
never@1999 | 566 | |
never@1999 | 567 | |
never@1999 | 568 | // Print out some state information about the current sweep and the |
never@1999 | 569 | // state of the code cache if it's requested. |
never@1999 | 570 | void NMethodSweeper::log_sweep(const char* msg, const char* format, ...) { |
never@1999 | 571 | if (PrintMethodFlushing) { |
iveresov@2764 | 572 | stringStream s; |
iveresov@2764 | 573 | // Dump code cache state into a buffer before locking the tty, |
iveresov@2764 | 574 | // because log_state() will use locks causing lock conflicts. |
iveresov@2764 | 575 | CodeCache::log_state(&s); |
iveresov@2764 | 576 | |
never@1999 | 577 | ttyLocker ttyl; |
never@1999 | 578 | tty->print("### sweeper: %s ", msg); |
never@1999 | 579 | if (format != NULL) { |
never@1999 | 580 | va_list ap; |
never@1999 | 581 | va_start(ap, format); |
never@1999 | 582 | tty->vprint(format, ap); |
never@1999 | 583 | va_end(ap); |
never@1999 | 584 | } |
iveresov@2764 | 585 | tty->print_cr(s.as_string()); |
never@1999 | 586 | } |
never@1999 | 587 | |
never@1999 | 588 | if (LogCompilation && (xtty != NULL)) { |
iveresov@2764 | 589 | stringStream s; |
iveresov@2764 | 590 | // Dump code cache state into a buffer before locking the tty, |
iveresov@2764 | 591 | // because log_state() will use locks causing lock conflicts. |
iveresov@2764 | 592 | CodeCache::log_state(&s); |
iveresov@2764 | 593 | |
never@1999 | 594 | ttyLocker ttyl; |
never@2001 | 595 | xtty->begin_elem("sweeper state='%s' traversals='" INTX_FORMAT "' ", msg, (intx)traversal_count()); |
never@1999 | 596 | if (format != NULL) { |
never@1999 | 597 | va_list ap; |
never@1999 | 598 | va_start(ap, format); |
never@1999 | 599 | xtty->vprint(format, ap); |
never@1999 | 600 | va_end(ap); |
never@1999 | 601 | } |
iveresov@2764 | 602 | xtty->print(s.as_string()); |
never@1999 | 603 | xtty->stamp(); |
never@1999 | 604 | xtty->end_elem(); |
never@1999 | 605 | } |
never@1999 | 606 | } |