root/MMgc/FixedMalloc.cpp

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DEFINITIONS

This source file includes following definitions.
  1. InitInstance
  2. DestroyInstance
  3. OutOfLineAlloc
  4. OutOfLineFree
  5. GetUsageInfo
  6. LargeAlloc
  7. LargeFree
  8. LargeSize
  9. Calloc
  10. GetTotalSize
  11. DumpMemoryInfo
  12. EnsureFixedMallocMemory
  13. AddToLargeObjectTracker
  14. RemoveFromLargeObjectTracker

/* -*- Mode: C++; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
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 * http://www.mozilla.org/MPL/
 *
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 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is [Open Source Virtual Machine.].
 *
 * The Initial Developer of the Original Code is
 * Adobe System Incorporated.
 * Portions created by the Initial Developer are Copyright (C) 2004-2006
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Adobe AS3 Team
 *
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 * either the GNU General Public License Version 2 or later (the "GPL"), or
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#include "MMgc.h"

namespace MMgc
{
        // kSizeClassIndex[] is an array that lets us quickly determine the allocator
        // to use for a given size, without division. A given allocation is rounded
        // up to the nearest multiple of 8, then downshifted 3 bits, and the index
        // tells us which allocator to use. (a special case is made for <= 4 bytes on
        // 32-bit systems in FindSizeClass to keep the table small.)

        // code to generate the table:
        //
        //              const int kMaxSizeClassIndex = (kLargestAlloc>>3)+1;
        //              uint8_t kSizeClassIndex[kMaxSizeClassIndex];
        //              printf("static const unsigned kMaxSizeClassIndex = %d;\n",kMaxSizeClassIndex);
        //              printf("static const uint8_t kSizeClassIndex[kMaxSizeClassIndex] = {\n");
        //              for (int size = 0; size <= kLargestAlloc; size += 8)
        //              {
        //                      int i = 0;
        //                      while (kSizeClasses[i] < size)
        //                      {
        //                              ++i;
        //                              AvmAssert(i < kNumSizeClasses);
        //                      }
        //                      AvmAssert((size>>3) < kMaxSizeClassIndex);
        //                      kSizeClassIndex[(size>>3)] = i;
        //                      if (size > 0) printf(",");
        //                      if (size % (16*8) == 0) printf("\n");
        //                      printf(" %d",i);
        //              }
        //              printf("};\n");

#ifdef MMGC_64BIT
        const int16_t FixedMalloc::kSizeClasses[kNumSizeClasses] = {
                8, 16, 24, 32, 40, 48, 56, 64, 72, 80, //0-9
                88, 96, 104, 112, 120, 128,     136, 144, 152, 160, //10-19
                168, 176, 192, 208, 224, 232, 248, 264, 288, 304, //20-29
                336, 360, 400, 448, 504, 576, 672, 800, 1008, 1344, //30-39
                2016, //40
        };

        /*static*/ const uint8_t FixedMalloc::kSizeClassIndex[kMaxSizeClassIndex] = {
                 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
                 15, 16, 17, 18, 19, 20, 21, 22, 22, 23, 23, 24, 24, 25, 26, 26,
                 27, 27, 28, 28, 28, 29, 29, 30, 30, 30, 30, 31, 31, 31, 32, 32,
                 32, 32, 32, 33, 33, 33, 33, 33, 33, 34, 34, 34, 34, 34, 34, 34,
                 35, 35, 35, 35, 35, 35, 35, 35, 35, 36, 36, 36, 36, 36, 36, 36,
                 36, 36, 36, 36, 36, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37,
                 37, 37, 37, 37, 37, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38,
                 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 39,
                 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39,
                 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39,
                 39, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 40,
                 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
                 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
                 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
                 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40,
                 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40
        };

#else
        const int16_t FixedMalloc::kSizeClasses[kNumSizeClasses] = {
                4, 8, 16, 24, 32, 40, 48, 56, 64, 72, //0-9
                80, 88, 96, 104, 112, 120, 128, 144, 160, 176, //10-19
        184, 192, 200, 208, 224, 232, 248, 264, 288, 312, //20-29
                336, 368, 400, 448, 504, 576, 672, 808, 1016, 1352, //30-39
                2032, //40
        };

        /*static*/ const uint8_t FixedMalloc::kSizeClassIndex[kMaxSizeClassIndex] = {
                0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 
                16, 17, 17, 18, 18, 19, 19, 20, 21, 22, 23, 24, 24, 25, 26, 26, 
                27, 27, 28, 28, 28, 29, 29, 29, 30, 30, 30, 31, 31, 31, 31, 32, 
                32, 32, 32, 33, 33, 33, 33, 33, 33, 34, 34, 34, 34, 34, 34, 34, 
                35, 35, 35, 35, 35, 35, 35, 35, 35, 36, 36, 36, 36, 36, 36, 36, 
                36, 36, 36, 36, 36, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 
                37, 37, 37, 37, 37, 37, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 
                38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 
                39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 
                39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 
                39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40, 
                40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 
                40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 
                40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 
                40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 
                40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40
        };

#endif

        /*static*/
        FixedMalloc *FixedMalloc::instance;

        void FixedMalloc::InitInstance(GCHeap* heap)
        {
                m_heap = heap;
                numLargeChunks = 0;
        #ifdef MMGC_MEMORY_PROFILER
                totalAskSizeLargeAllocs = 0;
        #endif
        #ifdef _DEBUG
                largeObjects = NULL;
        #endif

                // Create all the allocators up front (not lazy)
                // so that we don't have to check the pointers for
                // NULL on every allocation.
                for (int i=0; i<kNumSizeClasses; i++) {
                        // FIXME: by default FixedAlloc uses 4K chunks, for the
                        // more common size classes maybe we should use 8/16/32.
                        // FIXME: we could use FixedAllocLarge for the bigger size 
                        // classes but how to call the right Free would need to be work out
                        m_allocs[i].Init((uint32_t)kSizeClasses[i], heap);
                }

                FixedMalloc::instance = this;
        }

        void FixedMalloc::DestroyInstance()
        {
                for (int i=0; i<kNumSizeClasses; i++) {
                        m_allocs[i].Destroy();
                }               
                FixedMalloc::instance = NULL;
        }
        
        void* FASTCALL FixedMalloc::OutOfLineAlloc(size_t size, FixedMallocOpts flags)
        {
                // OPTIMIZEME?  Alloc() is inlined, as are some functions
                // it calls, but we could inline massively here.  As it
                // is, Alloc(size) expands to three calls: VMPI_lockAcquire,
                // FixedAlloc::Alloc/LargeAlloc, and VMPI_lockRelease.

                return Alloc(size, flags);
        }
        
        void FASTCALL FixedMalloc::OutOfLineFree(void* p)
        {
                // OPTIMIZEME?  Free() is inlined, as are some functions
                // it calls, but we could inline massively here.  As it is,
                // Free(p) expands into three calls: VMPI_lockAcquire,
                // FixedAlloc::Free/LargeFree, and VMPI_lockRelease.

                Free(p);
        }
        
        void FixedMalloc::GetUsageInfo(size_t& totalAskSize, size_t& totalAllocated)
        {
                totalAskSize = 0;
                totalAllocated = 0;
                for (int i=0; i<kNumSizeClasses; i++) {
                        size_t allocated = 0;
                        size_t ask = 0;
                        m_allocs[i].GetUsageInfo(ask, allocated);
                        totalAskSize += ask;
                        totalAllocated += allocated;
                }

#ifdef MMGC_MEMORY_PROFILER
                totalAskSize += totalAskSizeLargeAllocs;
#endif

                // not entirely accurate, assumes large allocations using all of last page (large ask size not stored)
                totalAllocated += numLargeChunks * GCHeap::kBlockSize;
        }

        void *FixedMalloc::LargeAlloc(size_t size, FixedMallocOpts flags)
        {
                GCHeap::CheckForAllocSizeOverflow(size, GCHeap::kBlockSize+DebugSize());
                
                size += DebugSize();

                int blocksNeeded = (int)GCHeap::SizeToBlocks(size);
                uint32_t gcheap_flags = GCHeap::kExpand;

                if((flags & kCanFail) != 0)
                        gcheap_flags |= GCHeap::kCanFail;
                if((flags & kZero) != 0)
                        gcheap_flags |= GCHeap::kZero;

                void *item = m_heap->Alloc(blocksNeeded, gcheap_flags);
                if(item)
                {
                        numLargeChunks += blocksNeeded;
                        
                        item = GetUserPointer(item);
#ifdef MMGC_HOOKS
                        if(m_heap->HooksEnabled())
                        {
#ifdef MMGC_MEMORY_PROFILER
                                totalAskSizeLargeAllocs += (size - DebugSize());
#endif
                                m_heap->AllocHook(item, size - DebugSize(), Size(item));
                        }
#endif // MMGC_HOOKS
                
#ifdef _DEBUG
                // fresh memory poisoning
                        if((flags & kZero) == 0)
                                memset(item, 0xfa, size - DebugSize());

                // enregister
                        AddToLargeObjectTracker(item);
#endif
                }
                return item;
        }
        
        
        void FixedMalloc::LargeFree(void *item)
        {
#ifdef _DEBUG
                RemoveFromLargeObjectTracker(item);
#endif
#ifdef MMGC_HOOKS
                if(m_heap->HooksEnabled()) {
        #ifdef MMGC_MEMORY_PROFILER
                        if(m_heap->GetProfiler())
                                totalAskSizeLargeAllocs -= m_heap->GetProfiler()->GetAskSize(item);
        #endif
                        m_heap->FinalizeHook(item, Size(item));
                        m_heap->FreeHook(item, Size(item), 0xfa);
                }
#endif
                numLargeChunks -= GCHeap::SizeToBlocks(LargeSize(item));
                m_heap->FreeNoProfile(GetRealPointer(item));
        }
        
        size_t FixedMalloc::LargeSize(const void *item)
        {
                return m_heap->Size(item) * GCHeap::kBlockSize;
        }

        void *FixedMalloc::Calloc(size_t count, size_t elsize, FixedMallocOpts opts)
        {
                return Alloc(GCHeap::CheckForCallocSizeOverflow(count, elsize), opts);
        }
        
        size_t FixedMalloc::GetTotalSize()
        {
                size_t total = numLargeChunks;
                for (int i=0; i<kNumSizeClasses; i++) {
                        total += m_allocs[i].GetNumChunks();
                }       
                return total;
        }

#ifdef MMGC_MEMORY_PROFILER
        void FixedMalloc::DumpMemoryInfo()
        {
                size_t inUse, ask;
                GetUsageInfo(ask, inUse);
                GCLog("[mem] FixedMalloc total %d pages inuse %d bytes ask %d bytes\n", GetTotalSize(), inUse, ask);
                for (int i=0; i<kNumSizeClasses; i++) {
                        m_allocs[i].GetUsageInfo(ask, inUse);
                        if( m_allocs[i].GetNumChunks() > 0)
                                GCLog("[mem] FixedMalloc[%d] total %d pages inuse %d bytes ask %d bytes\n", kSizeClasses[i], m_allocs[i].GetNumChunks(), inUse, ask);
                }
                GCLog("[mem] FixedMalloc[large] total %d pages\n", numLargeChunks);
        }
#endif

#ifdef _DEBUG
        // If this returns then item was definitely allocated by an allocator
        // owned by this FixedMalloc.
        void FixedMalloc::EnsureFixedMallocMemory(const void* item)
        {
                for (int i=0; i<kNumSizeClasses; i++) 
                        if (m_allocs[i].QueryOwnsObject(item))
                                return;
                
                for ( LargeObject* lo=largeObjects; lo != NULL ; lo=lo->next)
                        if (lo->item == item)
                                return;
                
                GCAssertMsg(false, "Trying to delete an object with FixedMalloc::Free that was not allocated with FixedMalloc::Alloc\n");
        }

        void FixedMalloc::AddToLargeObjectTracker(const void* item)
        {
                LargeObject* lo = (LargeObject*)Alloc(sizeof(LargeObject));
                lo->item = item;
                lo->next = largeObjects;
                largeObjects = lo;
        }
        
        void FixedMalloc::RemoveFromLargeObjectTracker(const void* item)
        {
                LargeObject *lo, *prev;
                for ( prev=NULL, lo=largeObjects ; lo != NULL ; prev=lo, lo=lo->next ) {
                        if (lo->item == item) {
                                if (prev != NULL)
                                        prev->next = lo->next;
                                else
                                        largeObjects = lo->next;
                                Free(lo);
                                return;
                        }
                }
        }
#endif
        
}


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