15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2008, Google Inc. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// All rights reserved. 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Redistribution and use in source and binary forms, with or without 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// modification, are permitted provided that the following conditions are 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// met: 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Redistributions of source code must retain the above copyright 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// notice, this list of conditions and the following disclaimer. 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Redistributions in binary form must reproduce the above 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// copyright notice, this list of conditions and the following disclaimer 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// in the documentation and/or other materials provided with the 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// distribution. 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Neither the name of Google Inc. nor the names of its 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// contributors may be used to endorse or promote products derived from 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// this software without specific prior written permission. 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// --- 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Author: Sanjay Ghemawat <opensource@google.com> 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef TCMALLOC_PAGE_HEAP_ALLOCATOR_H_ 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define TCMALLOC_PAGE_HEAP_ALLOCATOR_H_ 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <stddef.h> // for NULL, size_t 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "common.h" // for MetaDataAlloc 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "internal_logging.h" // for ASSERT 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace tcmalloc { 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Simple allocator for objects of a specified type. External locking 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// is required before accessing one of these objects. 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)template <class T> 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)class PageHeapAllocator { 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) public: 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // We use an explicit Init function because these variables are statically 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // allocated and their constructors might not have run by the time some 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // other static variable tries to allocate memory. 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Init() { 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ASSERT(sizeof(T) <= kAllocIncrement); 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) inuse_ = 0; 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_area_ = NULL; 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_avail_ = 0; 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_list_ = NULL; 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Reserve some space at the beginning to avoid fragmentation. 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Delete(New()); 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) T* New() { 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Consult free list 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void* result; 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (free_list_ != NULL) { 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) result = free_list_; 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_list_ = *(reinterpret_cast<void**>(result)); 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } else { 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (free_avail_ < sizeof(T)) { 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Need more room. We assume that MetaDataAlloc returns 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // suitably aligned memory. 715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_area_ = reinterpret_cast<char*>(MetaDataAlloc(kAllocIncrement)); 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (free_area_ == NULL) { 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Log(kCrash, __FILE__, __LINE__, 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) "FATAL ERROR: Out of memory trying to allocate internal " 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) "tcmalloc data (bytes, object-size)", 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) kAllocIncrement, sizeof(T)); 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_avail_ = kAllocIncrement; 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) result = free_area_; 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_area_ += sizeof(T); 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_avail_ -= sizeof(T); 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) inuse_++; 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return reinterpret_cast<T*>(result); 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Delete(T* p) { 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *(reinterpret_cast<void**>(p)) = free_list_; 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) free_list_ = p; 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) inuse_--; 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int inuse() const { return inuse_; } 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) private: 975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // How much to allocate from system at a time 985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const int kAllocIncrement = 128 << 10; 995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Free area from which to carve new objects 1015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) char* free_area_; 1025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) size_t free_avail_; 1035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Free list of already carved objects 1055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void* free_list_; 1065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Number of allocated but unfreed objects 1085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int inuse_; 1095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 1105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace tcmalloc 1125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif // TCMALLOC_PAGE_HEAP_ALLOCATOR_H_ 114