Mercurial > hg > graal-compiler
view src/share/vm/code/oopRecorder.cpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
---|---|
date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | f95d63e2154a |
children | da91efe96a93 |
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/* * Copyright (c) 1998, 2010, 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 "code/oopRecorder.hpp" #include "memory/allocation.inline.hpp" #include "oops/oop.inline.hpp" #ifdef ASSERT int OopRecorder::_find_index_calls = 0; int OopRecorder::_hit_indexes = 0; int OopRecorder::_missed_indexes = 0; #endif //ASSERT OopRecorder::OopRecorder(Arena* arena) { _handles = NULL; _indexes = NULL; _arena = arena; _complete = false; } OopRecorder::IndexCache::IndexCache() { assert(first_index > 0, "initial zero state of cache must be invalid index"); Copy::zero_to_bytes(&_cache[0], sizeof(_cache)); } int OopRecorder::oop_size() { _complete = true; if (_handles == NULL) return 0; return _handles->length() * sizeof(oop); } void OopRecorder::copy_to(nmethod* nm) { assert(_complete, "must be frozen"); maybe_initialize(); // get non-null handles, even if we have no oops nm->copy_oops(_handles); } void OopRecorder::maybe_initialize() { if (_handles == NULL) { if (_arena != NULL) { _handles = new(_arena) GrowableArray<jobject>(_arena, 10, 0, 0); _no_finds = new(_arena) GrowableArray<int>( _arena, 10, 0, 0); } else { _handles = new GrowableArray<jobject>(10, 0, 0); _no_finds = new GrowableArray<int>( 10, 0, 0); } } } jobject OopRecorder::handle_at(int index) { // there is always a NULL virtually present as first object if (index == null_index) return NULL; return _handles->at(index - first_index); } // Local definition. Used only in this module. inline bool OopRecorder::is_real_jobject(jobject h) { return h != NULL && h != (jobject)Universe::non_oop_word(); } int OopRecorder::add_handle(jobject h, bool make_findable) { assert(!_complete, "cannot allocate more elements after size query"); maybe_initialize(); // indexing uses 1 as an origin--0 means null int index = _handles->length() + first_index; _handles->append(h); // Support correct operation of find_index(). assert(!(make_findable && !is_real_jobject(h)), "nulls are not findable"); if (make_findable) { // This index may be returned from find_index(). if (_indexes != NULL) { int* cloc = _indexes->cache_location(h); _indexes->set_cache_location_index(cloc, index); } else if (index == index_cache_threshold && _arena != NULL) { _indexes = new(_arena) IndexCache(); for (int i = 0; i < _handles->length(); i++) { // Load the cache with pre-existing elements. int index0 = i + first_index; if (_no_finds->contains(index0)) continue; int* cloc = _indexes->cache_location(_handles->at(i)); _indexes->set_cache_location_index(cloc, index0); } } } else if (is_real_jobject(h)) { // Remember that this index is not to be returned from find_index(). // This case is rare, because most or all uses of allocate_index pass // a jobject argument of NULL or Universe::non_oop_word. // Thus, the expected length of _no_finds is zero. _no_finds->append(index); } return index; } int OopRecorder::maybe_find_index(jobject h) { debug_only(_find_index_calls++); assert(!_complete, "cannot allocate more elements after size query"); maybe_initialize(); if (h == NULL) return null_index; assert(is_real_jobject(h), "must be valid jobject"); int* cloc = (_indexes == NULL)? NULL: _indexes->cache_location(h); if (cloc != NULL) { int cindex = _indexes->cache_location_index(cloc); if (cindex == 0) { return -1; // We know this handle is completely new. } if (cindex >= first_index && _handles->at(cindex - first_index) == h) { debug_only(_hit_indexes++); return cindex; } if (!_indexes->cache_location_collision(cloc)) { return -1; // We know the current cache occupant is unique to that cloc. } } // Not found in cache, due to a cache collision. (Or, no cache at all.) // Do a linear search, most recent to oldest. for (int i = _handles->length() - 1; i >= 0; i--) { if (_handles->at(i) == h) { int findex = i + first_index; if (_no_finds->contains(findex)) continue; // oops; skip this one if (cloc != NULL) { _indexes->set_cache_location_index(cloc, findex); } debug_only(_missed_indexes++); return findex; } } return -1; }