src/gc/large_object_space.cc - platform/art - Git at Google

 /*
  * Copyright (C) 2012 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "large_object_space.h"
 #include "UniquePtr.h"
 #include "dlmalloc.h"
 #include "file.h"
 #include "image.h"
 #include "logging.h"
 #include "os.h"
 #include "space_bitmap.h"
 #include "stl_util.h"
 #include "utils.h"

 namespace art {

 void LargeObjectSpace::SwapBitmaps() {
   SpaceSetMap* temp_live_objects = live_objects_.release();
   live_objects_.reset(mark_objects_.release());
   mark_objects_.reset(temp_live_objects);
   // Swap names to get more descriptive diagnostics.
   std::string temp_name = live_objects_->GetName();
   live_objects_->SetName(mark_objects_->GetName());
   mark_objects_->SetName(temp_name);
 }

 LargeObjectSpace::LargeObjectSpace(const std::string& name)
     : DiscontinuousSpace(name, kGcRetentionPolicyAlwaysCollect),
       num_bytes_allocated_(0), num_objects_allocated_(0), total_bytes_allocated_(0),
       total_objects_allocated_(0) {
   live_objects_.reset(new SpaceSetMap("large live objects"));
   mark_objects_.reset(new SpaceSetMap("large marked objects"));
 }


 void LargeObjectSpace::CopyLiveToMarked() {
   mark_objects_->CopyFrom(*live_objects_.get());
 }

 LargeObjectMapSpace::LargeObjectMapSpace(const std::string& name)
     : LargeObjectSpace(name),
       lock_("large object space lock", kAllocSpaceLock)
 {

 }

 LargeObjectMapSpace* LargeObjectMapSpace::Create(const std::string& name) {
   return new LargeObjectMapSpace(name);
 }

 Object* LargeObjectMapSpace::Alloc(Thread* self, size_t num_bytes) {
   MemMap* mem_map = MemMap::MapAnonymous("allocation", NULL, num_bytes, PROT_READ | PROT_WRITE);
   if (mem_map == NULL) {
     return NULL;
   }
   MutexLock mu(self, lock_);
   Object* obj = reinterpret_cast<Object*>(mem_map->Begin());
   large_objects_.push_back(obj);
   mem_maps_.Put(obj, mem_map);
   size_t allocation_size = mem_map->Size();
   num_bytes_allocated_ += allocation_size;
   total_bytes_allocated_ += allocation_size;
   ++num_objects_allocated_;
   ++total_objects_allocated_;
   return obj;
 }

 size_t LargeObjectMapSpace::Free(Thread* self, Object* ptr) {
   MutexLock mu(self, lock_);
   MemMaps::iterator found = mem_maps_.find(ptr);
   CHECK(found != mem_maps_.end()) << "Attempted to free large object which was not live";
   DCHECK_GE(num_bytes_allocated_, found->second->Size());
   size_t allocation_size = found->second->Size();
   num_bytes_allocated_ -= allocation_size;
   --num_objects_allocated_;
   delete found->second;
   mem_maps_.erase(found);
   return allocation_size;
 }

 size_t LargeObjectMapSpace::AllocationSize(const Object* obj) {
   MutexLock mu(Thread::Current(), lock_);
   MemMaps::iterator found = mem_maps_.find(const_cast<Object*>(obj));
   CHECK(found != mem_maps_.end()) << "Attempted to get size of a large object which is not live";
   return found->second->Size();
 }

 size_t LargeObjectSpace::FreeList(Thread* self, size_t num_ptrs, Object** ptrs) {
   size_t total = 0;
   for (size_t i = 0; i < num_ptrs; ++i) {
     if (kDebugSpaces) {
       CHECK(Contains(ptrs[i]));
     }
     total += Free(self, ptrs[i]);
   }
   return total;
 }

 void LargeObjectMapSpace::Walk(DlMallocSpace::WalkCallback callback, void* arg) {
   MutexLock mu(Thread::Current(), lock_);
   for (MemMaps::iterator it = mem_maps_.begin(); it != mem_maps_.end(); ++it) {
     MemMap* mem_map = it->second;
     callback(mem_map->Begin(), mem_map->End(), mem_map->Size(), arg);
     callback(NULL, NULL, 0, arg);
   }
 }

 bool LargeObjectMapSpace::Contains(const Object* obj) const {
   MutexLock mu(Thread::Current(), lock_);
   return mem_maps_.find(const_cast<Object*>(obj)) != mem_maps_.end();
 }

 FreeListSpace* FreeListSpace::Create(const std::string& name, byte* requested_begin, size_t size) {
   CHECK(size % kAlignment == 0);
   MemMap* mem_map = MemMap::MapAnonymous(name.c_str(), requested_begin, size,
                                          PROT_READ | PROT_WRITE);
   CHECK(mem_map != NULL) << "Failed to allocate large object space mem map";
   return new FreeListSpace(name, mem_map, mem_map->Begin(), mem_map->End());
 }

 FreeListSpace::FreeListSpace(const std::string& name, MemMap* mem_map, byte* begin, byte* end)
     : LargeObjectSpace(name),
       begin_(begin),
       end_(end),
       mem_map_(mem_map),
       lock_("free list space lock", kAllocSpaceLock) {
   chunks_.resize(Size() / kAlignment + 1);
   // Add a dummy chunk so we don't need to handle chunks having no next chunk.
   chunks_.back().SetSize(kAlignment, false);
   // Start out with one large free chunk.
   AddFreeChunk(begin_, end_ - begin_, NULL);
 }

 FreeListSpace::~FreeListSpace() {

 }

 void FreeListSpace::AddFreeChunk(void* address, size_t size, Chunk* previous) {
   Chunk* chunk = ChunkFromAddr(address);
   chunk->SetSize(size, true);
   chunk->SetPrevious(previous);
   Chunk* next_chunk = GetNextChunk(chunk);
   next_chunk->SetPrevious(chunk);
   free_chunks_.insert(chunk);
 }

 FreeListSpace::Chunk* FreeListSpace::ChunkFromAddr(void* address) {
   size_t offset = reinterpret_cast<byte*>(address) - Begin();
   DCHECK(IsAligned<kAlignment>(offset));
   DCHECK_LT(offset, Size());
   return &chunks_[offset / kAlignment];
 }

 void* FreeListSpace::AddrFromChunk(Chunk* chunk) {
   return reinterpret_cast<void*>(Begin() + (chunk - &chunks_.front()) * kAlignment);
 }

 void FreeListSpace::RemoveFreeChunk(Chunk* chunk) {
   // TODO: C++0x
   // TODO: Improve performance, this might be slow.
   std::pair<FreeChunks::iterator, FreeChunks::iterator> range = free_chunks_.equal_range(chunk);
   for (FreeChunks::iterator it = range.first; it != range.second; ++it) {
     if (*it == chunk) {
       free_chunks_.erase(it);
       return;
     }
   }
 }

 void FreeListSpace::Walk(DlMallocSpace::WalkCallback callback, void* arg) {
   MutexLock mu(Thread::Current(), lock_);
   for (Chunk* chunk = &chunks_.front(); chunk < &chunks_.back(); ) {
     if (!chunk->IsFree()) {
       size_t size = chunk->GetSize();
       void* begin = AddrFromChunk(chunk);
       void* end = reinterpret_cast<void*>(reinterpret_cast<byte*>(begin) + size);
       callback(begin, end, size, arg);
       callback(NULL, NULL, 0, arg);
     }
     chunk = GetNextChunk(chunk);
   }
 }

 size_t FreeListSpace::Free(Thread* self, Object* obj) {
   MutexLock mu(self, lock_);
   CHECK(Contains(obj));
   // Check adjacent chunks to see if we need to combine.
   Chunk* chunk = ChunkFromAddr(obj);
   CHECK(!chunk->IsFree());

   size_t allocation_size = chunk->GetSize();
   madvise(obj, allocation_size, MADV_DONTNEED);
   num_objects_allocated_--;
   num_bytes_allocated_ -= allocation_size;
   Chunk* prev = chunk->GetPrevious();
   Chunk* next = GetNextChunk(chunk);

   // Combine any adjacent free chunks
   size_t extra_size = chunk->GetSize();
   if (next->IsFree()) {
     extra_size += next->GetSize();
     RemoveFreeChunk(next);
   }
   if (prev != NULL && prev->IsFree()) {
     RemoveFreeChunk(prev);
     AddFreeChunk(AddrFromChunk(prev), prev->GetSize() + extra_size, prev->GetPrevious());
   } else {
     AddFreeChunk(AddrFromChunk(chunk), extra_size, prev);
   }
   return allocation_size;
 }

 bool FreeListSpace::Contains(const Object* obj) const {
   return mem_map_->HasAddress(obj);
 }

 FreeListSpace::Chunk* FreeListSpace::GetNextChunk(Chunk* chunk) {
   return chunk + chunk->GetSize() / kAlignment;
 }

 size_t FreeListSpace::AllocationSize(const Object* obj) {
   Chunk* chunk = ChunkFromAddr(const_cast<Object*>(obj));
   CHECK(!chunk->IsFree());
   return chunk->GetSize();
 }

 Object* FreeListSpace::Alloc(Thread* self, size_t num_bytes) {
   MutexLock mu(self, lock_);
   num_bytes = RoundUp(num_bytes, kAlignment);
   Chunk temp;
   temp.SetSize(num_bytes);
   // Find the smallest chunk at least num_bytes in size.
   FreeChunks::iterator found = free_chunks_.lower_bound(&temp);
   if (found == free_chunks_.end()) {
     // Out of memory, or too much fragmentation.
     return NULL;
   }
   Chunk* chunk = *found;
   free_chunks_.erase(found);
   CHECK(chunk->IsFree());
   void* addr = AddrFromChunk(chunk);
   size_t chunk_size = chunk->GetSize();
   chunk->SetSize(num_bytes);
   if (chunk_size > num_bytes) {
     // Split the chunk into two chunks.
     Chunk* new_chunk = GetNextChunk(chunk);
     AddFreeChunk(AddrFromChunk(new_chunk), chunk_size - num_bytes, chunk);
   }

   num_objects_allocated_++;
   total_objects_allocated_++;
   num_bytes_allocated_ += num_bytes;
   total_bytes_allocated_ += num_bytes;
   return reinterpret_cast<Object*>(addr);
 }

 void FreeListSpace::Dump(std::ostream& os) const{
   os << GetName() << " -"
      << " begin: " << reinterpret_cast<void*>(Begin())
      << " end: " << reinterpret_cast<void*>(End());
 }

 }
	/*
	* Copyright (C) 2012 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "large_object_space.h"
	#include "UniquePtr.h"
	#include "dlmalloc.h"
	#include "file.h"
	#include "image.h"
	#include "logging.h"
	#include "os.h"
	#include "space_bitmap.h"
	#include "stl_util.h"
	#include "utils.h"

	namespace art {

	void LargeObjectSpace::SwapBitmaps() {
	SpaceSetMap* temp_live_objects = live_objects_.release();
	live_objects_.reset(mark_objects_.release());
	mark_objects_.reset(temp_live_objects);
	// Swap names to get more descriptive diagnostics.
	std::string temp_name = live_objects_->GetName();
	live_objects_->SetName(mark_objects_->GetName());
	mark_objects_->SetName(temp_name);
	}

	LargeObjectSpace::LargeObjectSpace(const std::string& name)
	: DiscontinuousSpace(name, kGcRetentionPolicyAlwaysCollect),
	num_bytes_allocated_(0), num_objects_allocated_(0), total_bytes_allocated_(0),
	total_objects_allocated_(0) {
	live_objects_.reset(new SpaceSetMap("large live objects"));
	mark_objects_.reset(new SpaceSetMap("large marked objects"));
	}


	void LargeObjectSpace::CopyLiveToMarked() {
	mark_objects_->CopyFrom(*live_objects_.get());
	}

	LargeObjectMapSpace::LargeObjectMapSpace(const std::string& name)
	: LargeObjectSpace(name),
	lock_("large object space lock", kAllocSpaceLock)
	{

	}

	LargeObjectMapSpace* LargeObjectMapSpace::Create(const std::string& name) {
	return new LargeObjectMapSpace(name);
	}

	Object* LargeObjectMapSpace::Alloc(Thread* self, size_t num_bytes) {
	MemMap* mem_map = MemMap::MapAnonymous("allocation", NULL, num_bytes, PROT_READ \| PROT_WRITE);
	if (mem_map == NULL) {
	return NULL;
	}
	MutexLock mu(self, lock_);
	Object* obj = reinterpret_cast<Object*>(mem_map->Begin());
	large_objects_.push_back(obj);
	mem_maps_.Put(obj, mem_map);
	size_t allocation_size = mem_map->Size();
	num_bytes_allocated_ += allocation_size;
	total_bytes_allocated_ += allocation_size;
	++num_objects_allocated_;
	++total_objects_allocated_;
	return obj;
	}

	size_t LargeObjectMapSpace::Free(Thread* self, Object* ptr) {
	MutexLock mu(self, lock_);
	MemMaps::iterator found = mem_maps_.find(ptr);
	CHECK(found != mem_maps_.end()) << "Attempted to free large object which was not live";
	DCHECK_GE(num_bytes_allocated_, found->second->Size());
	size_t allocation_size = found->second->Size();
	num_bytes_allocated_ -= allocation_size;
	--num_objects_allocated_;
	delete found->second;
	mem_maps_.erase(found);
	return allocation_size;
	}

	size_t LargeObjectMapSpace::AllocationSize(const Object* obj) {
	MutexLock mu(Thread::Current(), lock_);
	MemMaps::iterator found = mem_maps_.find(const_cast<Object*>(obj));
	CHECK(found != mem_maps_.end()) << "Attempted to get size of a large object which is not live";
	return found->second->Size();
	}

	size_t LargeObjectSpace::FreeList(Thread* self, size_t num_ptrs, Object** ptrs) {
	size_t total = 0;
	for (size_t i = 0; i < num_ptrs; ++i) {
	if (kDebugSpaces) {
	CHECK(Contains(ptrs[i]));
	}
	total += Free(self, ptrs[i]);
	}
	return total;
	}

	void LargeObjectMapSpace::Walk(DlMallocSpace::WalkCallback callback, void* arg) {
	MutexLock mu(Thread::Current(), lock_);
	for (MemMaps::iterator it = mem_maps_.begin(); it != mem_maps_.end(); ++it) {
	MemMap* mem_map = it->second;
	callback(mem_map->Begin(), mem_map->End(), mem_map->Size(), arg);
	callback(NULL, NULL, 0, arg);
	}
	}

	bool LargeObjectMapSpace::Contains(const Object* obj) const {
	MutexLock mu(Thread::Current(), lock_);
	return mem_maps_.find(const_cast<Object*>(obj)) != mem_maps_.end();
	}

	FreeListSpace* FreeListSpace::Create(const std::string& name, byte* requested_begin, size_t size) {
	CHECK(size % kAlignment == 0);
	MemMap* mem_map = MemMap::MapAnonymous(name.c_str(), requested_begin, size,
	PROT_READ \| PROT_WRITE);
	CHECK(mem_map != NULL) << "Failed to allocate large object space mem map";
	return new FreeListSpace(name, mem_map, mem_map->Begin(), mem_map->End());
	}

	FreeListSpace::FreeListSpace(const std::string& name, MemMap* mem_map, byte* begin, byte* end)
	: LargeObjectSpace(name),
	begin_(begin),
	end_(end),
	mem_map_(mem_map),
	lock_("free list space lock", kAllocSpaceLock) {
	chunks_.resize(Size() / kAlignment + 1);
	// Add a dummy chunk so we don't need to handle chunks having no next chunk.
	chunks_.back().SetSize(kAlignment, false);
	// Start out with one large free chunk.
	AddFreeChunk(begin_, end_ - begin_, NULL);
	}

	FreeListSpace::~FreeListSpace() {

	}

	void FreeListSpace::AddFreeChunk(void* address, size_t size, Chunk* previous) {
	Chunk* chunk = ChunkFromAddr(address);
	chunk->SetSize(size, true);
	chunk->SetPrevious(previous);
	Chunk* next_chunk = GetNextChunk(chunk);
	next_chunk->SetPrevious(chunk);
	free_chunks_.insert(chunk);
	}

	FreeListSpace::Chunk* FreeListSpace::ChunkFromAddr(void* address) {
	size_t offset = reinterpret_cast<byte*>(address) - Begin();
	DCHECK(IsAligned<kAlignment>(offset));
	DCHECK_LT(offset, Size());
	return &chunks_[offset / kAlignment];
	}

	void* FreeListSpace::AddrFromChunk(Chunk* chunk) {
	return reinterpret_cast<void>(Begin() + (chunk - &chunks_.front()) kAlignment);
	}

	void FreeListSpace::RemoveFreeChunk(Chunk* chunk) {
	// TODO: C++0x
	// TODO: Improve performance, this might be slow.
	std::pair<FreeChunks::iterator, FreeChunks::iterator> range = free_chunks_.equal_range(chunk);
	for (FreeChunks::iterator it = range.first; it != range.second; ++it) {
	if (*it == chunk) {
	free_chunks_.erase(it);
	return;
	}
	}
	}

	void FreeListSpace::Walk(DlMallocSpace::WalkCallback callback, void* arg) {
	MutexLock mu(Thread::Current(), lock_);
	for (Chunk* chunk = &chunks_.front(); chunk < &chunks_.back(); ) {
	if (!chunk->IsFree()) {
	size_t size = chunk->GetSize();
	void* begin = AddrFromChunk(chunk);
	void* end = reinterpret_cast<void>(reinterpret_cast<byte>(begin) + size);
	callback(begin, end, size, arg);
	callback(NULL, NULL, 0, arg);
	}
	chunk = GetNextChunk(chunk);
	}
	}

	size_t FreeListSpace::Free(Thread* self, Object* obj) {
	MutexLock mu(self, lock_);
	CHECK(Contains(obj));
	// Check adjacent chunks to see if we need to combine.
	Chunk* chunk = ChunkFromAddr(obj);
	CHECK(!chunk->IsFree());

	size_t allocation_size = chunk->GetSize();
	madvise(obj, allocation_size, MADV_DONTNEED);
	num_objects_allocated_--;
	num_bytes_allocated_ -= allocation_size;
	Chunk* prev = chunk->GetPrevious();
	Chunk* next = GetNextChunk(chunk);

	// Combine any adjacent free chunks
	size_t extra_size = chunk->GetSize();
	if (next->IsFree()) {
	extra_size += next->GetSize();
	RemoveFreeChunk(next);
	}
	if (prev != NULL && prev->IsFree()) {
	RemoveFreeChunk(prev);
	AddFreeChunk(AddrFromChunk(prev), prev->GetSize() + extra_size, prev->GetPrevious());
	} else {
	AddFreeChunk(AddrFromChunk(chunk), extra_size, prev);
	}
	return allocation_size;
	}

	bool FreeListSpace::Contains(const Object* obj) const {
	return mem_map_->HasAddress(obj);
	}

	FreeListSpace::Chunk* FreeListSpace::GetNextChunk(Chunk* chunk) {
	return chunk + chunk->GetSize() / kAlignment;
	}

	size_t FreeListSpace::AllocationSize(const Object* obj) {
	Chunk* chunk = ChunkFromAddr(const_cast<Object*>(obj));
	CHECK(!chunk->IsFree());
	return chunk->GetSize();
	}

	Object* FreeListSpace::Alloc(Thread* self, size_t num_bytes) {
	MutexLock mu(self, lock_);
	num_bytes = RoundUp(num_bytes, kAlignment);
	Chunk temp;
	temp.SetSize(num_bytes);
	// Find the smallest chunk at least num_bytes in size.
	FreeChunks::iterator found = free_chunks_.lower_bound(&temp);
	if (found == free_chunks_.end()) {
	// Out of memory, or too much fragmentation.
	return NULL;
	}
	Chunk* chunk = *found;
	free_chunks_.erase(found);
	CHECK(chunk->IsFree());
	void* addr = AddrFromChunk(chunk);
	size_t chunk_size = chunk->GetSize();
	chunk->SetSize(num_bytes);
	if (chunk_size > num_bytes) {
	// Split the chunk into two chunks.
	Chunk* new_chunk = GetNextChunk(chunk);
	AddFreeChunk(AddrFromChunk(new_chunk), chunk_size - num_bytes, chunk);
	}

	num_objects_allocated_++;
	total_objects_allocated_++;
	num_bytes_allocated_ += num_bytes;
	total_bytes_allocated_ += num_bytes;
	return reinterpret_cast<Object*>(addr);
	}

	void FreeListSpace::Dump(std::ostream& os) const{
	os << GetName() << " -"
	<< " begin: " << reinterpret_cast<void*>(Begin())
	<< " end: " << reinterpret_cast<void*>(End());
	}

	}