Mercurial > hg > graal-compiler
view src/share/vm/gc_implementation/g1/g1AllocRegion.hpp @ 12333:cacc4c6bfc80
8025233: Move sun.invoke.Stable into java.lang.invoke package
Reviewed-by: twisti, iveresov
author | vlivanov |
---|---|
date | Wed, 02 Oct 2013 06:17:10 -0700 |
parents | 720b6a76dd9d |
children | 9412b1915547 1b422ef5288a |
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/* * Copyright (c) 2011, 2012, 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. * */ #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCREGION_HPP #define SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCREGION_HPP #include "gc_implementation/g1/heapRegion.hpp" class G1CollectedHeap; // 0 -> no tracing, 1 -> basic tracing, 2 -> basic + allocation tracing #define G1_ALLOC_REGION_TRACING 0 class ar_ext_msg; // A class that holds a region that is active in satisfying allocation // requests, potentially issued in parallel. When the active region is // full it will be retired and replaced with a new one. The // implementation assumes that fast-path allocations will be lock-free // and a lock will need to be taken when the active region needs to be // replaced. class G1AllocRegion VALUE_OBJ_CLASS_SPEC { friend class ar_ext_msg; private: // The active allocating region we are currently allocating out // of. The invariant is that if this object is initialized (i.e., // init() has been called and release() has not) then _alloc_region // is either an active allocating region or the dummy region (i.e., // it can never be NULL) and this object can be used to satisfy // allocation requests. If this object is not initialized // (i.e. init() has not been called or release() has been called) // then _alloc_region is NULL and this object should not be used to // satisfy allocation requests (it was done this way to force the // correct use of init() and release()). HeapRegion* _alloc_region; // It keeps track of the distinct number of regions that are used // for allocation in the active interval of this object, i.e., // between a call to init() and a call to release(). The count // mostly includes regions that are freshly allocated, as well as // the region that is re-used using the set() method. This count can // be used in any heuristics that might want to bound how many // distinct regions this object can used during an active interval. uint _count; // When we set up a new active region we save its used bytes in this // field so that, when we retire it, we can calculate how much space // we allocated in it. size_t _used_bytes_before; // When true, indicates that allocate calls should do BOT updates. const bool _bot_updates; // Useful for debugging and tracing. const char* _name; // A dummy region (i.e., it's been allocated specially for this // purpose and it is not part of the heap) that is full (i.e., top() // == end()). When we don't have a valid active region we make // _alloc_region point to this. This allows us to skip checking // whether the _alloc_region is NULL or not. static HeapRegion* _dummy_region; // Some of the methods below take a bot_updates parameter. Its value // should be the same as the _bot_updates field. The idea is that // the parameter will be a constant for a particular alloc region // and, given that these methods will be hopefully inlined, the // compiler should compile out the test. // Perform a non-MT-safe allocation out of the given region. static inline HeapWord* allocate(HeapRegion* alloc_region, size_t word_size, bool bot_updates); // Perform a MT-safe allocation out of the given region. static inline HeapWord* par_allocate(HeapRegion* alloc_region, size_t word_size, bool bot_updates); // Ensure that the region passed as a parameter has been filled up // so that noone else can allocate out of it any more. static void fill_up_remaining_space(HeapRegion* alloc_region, bool bot_updates); // Retire the active allocating region. If fill_up is true then make // sure that the region is full before we retire it so that noone // else can allocate out of it. void retire(bool fill_up); // Allocate a new active region and use it to perform a word_size // allocation. The force parameter will be passed on to // G1CollectedHeap::allocate_new_alloc_region() and tells it to try // to allocate a new region even if the max has been reached. HeapWord* new_alloc_region_and_allocate(size_t word_size, bool force); void fill_in_ext_msg(ar_ext_msg* msg, const char* message); protected: // For convenience as subclasses use it. static G1CollectedHeap* _g1h; virtual HeapRegion* allocate_new_region(size_t word_size, bool force) = 0; virtual void retire_region(HeapRegion* alloc_region, size_t allocated_bytes) = 0; G1AllocRegion(const char* name, bool bot_updates); public: static void setup(G1CollectedHeap* g1h, HeapRegion* dummy_region); HeapRegion* get() const { // Make sure that the dummy region does not escape this class. return (_alloc_region == _dummy_region) ? NULL : _alloc_region; } uint count() { return _count; } // The following two are the building blocks for the allocation method. // First-level allocation: Should be called without holding a // lock. It will try to allocate lock-free out of the active region, // or return NULL if it was unable to. inline HeapWord* attempt_allocation(size_t word_size, bool bot_updates); // Second-level allocation: Should be called while holding a // lock. It will try to first allocate lock-free out of the active // region or, if it's unable to, it will try to replace the active // alloc region with a new one. We require that the caller takes the // appropriate lock before calling this so that it is easier to make // it conform to its locking protocol. inline HeapWord* attempt_allocation_locked(size_t word_size, bool bot_updates); // Should be called to allocate a new region even if the max of this // type of regions has been reached. Should only be called if other // allocation attempts have failed and we are not holding a valid // active region. inline HeapWord* attempt_allocation_force(size_t word_size, bool bot_updates); // Should be called before we start using this object. void init(); // This can be used to set the active region to a specific // region. (Use Example: we try to retain the last old GC alloc // region that we've used during a GC and we can use set() to // re-instate it at the beginning of the next GC.) void set(HeapRegion* alloc_region); // Should be called when we want to release the active region which // is returned after it's been retired. HeapRegion* release(); #if G1_ALLOC_REGION_TRACING void trace(const char* str, size_t word_size = 0, HeapWord* result = NULL); #else // G1_ALLOC_REGION_TRACING void trace(const char* str, size_t word_size = 0, HeapWord* result = NULL) { } #endif // G1_ALLOC_REGION_TRACING }; class ar_ext_msg : public err_msg { public: ar_ext_msg(G1AllocRegion* alloc_region, const char *message) : err_msg("") { alloc_region->fill_in_ext_msg(this, message); } }; #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCREGION_HPP