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@ -0,0 +1,811 @@
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/*-------------------------------------------------------------------------
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*
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* bump.c
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* Bump allocator definitions.
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*
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* Bump is a MemoryContext implementation designed for memory usages which
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* require allocating a large number of chunks, none of which ever need to be
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* pfree'd or realloc'd. Chunks allocated by this context have no chunk header
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* and operations which ordinarily require looking at the chunk header cannot
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* be performed. For example, pfree, realloc, GetMemoryChunkSpace and
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* GetMemoryChunkContext are all not possible with bump allocated chunks. The
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* only way to release memory allocated by this context type is to reset or
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* delete the context.
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*
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* Portions Copyright (c) 2024, PostgreSQL Global Development Group
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*
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* IDENTIFICATION
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* src/backend/utils/mmgr/bump.c
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*
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*
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* Bump is best suited to cases which require a large number of short-lived
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* chunks where performance matters. Because bump allocated chunks don't
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* have a chunk header, it can fit more chunks on each block. This means we
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* can do more with less memory and fewer cache lines. The reason it's best
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* suited for short-lived usages of memory is that ideally, pointers to bump
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* allocated chunks won't be visible to a large amount of code. The more
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* code that operates on memory allocated by this allocator, the more chances
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* that some code will try to perform a pfree or one of the other operations
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* which are made impossible due to the lack of chunk header. In order to
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* detect accidental usage of the various disallowed operations, we do add a
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* MemoryChunk chunk header in MEMORY_CONTEXT_CHECKING builds and have the
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* various disallowed functions raise an ERROR.
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*
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* Allocations are MAXALIGNed.
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "lib/ilist.h"
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#include "port/pg_bitutils.h"
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#include "utils/memdebug.h"
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#include "utils/memutils.h"
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#include "utils/memutils_memorychunk.h"
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#include "utils/memutils_internal.h"
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#define Bump_BLOCKHDRSZ MAXALIGN(sizeof(BumpBlock))
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/* No chunk header unless built with MEMORY_CONTEXT_CHECKING */
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#ifdef MEMORY_CONTEXT_CHECKING
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#define Bump_CHUNKHDRSZ sizeof(MemoryChunk)
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#else
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#define Bump_CHUNKHDRSZ 0
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#endif
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#define Bump_CHUNK_FRACTION 8
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/* The keeper block is allocated in the same allocation as the set */
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#define KeeperBlock(set) ((BumpBlock *) ((char *) (set) + sizeof(BumpContext)))
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#define IsKeeperBlock(set, blk) (KeeperBlock(set) == (blk))
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typedef struct BumpBlock BumpBlock; /* forward reference */
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typedef struct BumpContext
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{
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MemoryContextData header; /* Standard memory-context fields */
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/* Bump context parameters */
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uint32 initBlockSize; /* initial block size */
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uint32 maxBlockSize; /* maximum block size */
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uint32 nextBlockSize; /* next block size to allocate */
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uint32 allocChunkLimit; /* effective chunk size limit */
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dlist_head blocks; /* list of blocks with the block currently
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* being filled at the head */
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} BumpContext;
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/*
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* BumpBlock
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* BumpBlock is the unit of memory that is obtained by bump.c from
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* malloc(). It contains zero or more allocations, which are the
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* units requested by palloc().
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*/
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struct BumpBlock
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{
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dlist_node node; /* doubly-linked list of blocks */
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#ifdef MEMORY_CONTEXT_CHECKING
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BumpContext *context; /* pointer back to the owning context */
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#endif
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char *freeptr; /* start of free space in this block */
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char *endptr; /* end of space in this block */
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};
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/*
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* BumpIsValid
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* True iff set is valid bump context.
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*/
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#define BumpIsValid(set) \
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(PointerIsValid(set) && IsA(set, BumpContext))
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/*
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* BumpBlockIsValid
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* True iff block is valid block of a bump context
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*/
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#define BumpBlockIsValid(block) \
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(PointerIsValid(block) && BumpIsValid((block)->context))
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/*
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* We always store external chunks on a dedicated block. This makes fetching
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* the block from an external chunk easy since it's always the first and only
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* chunk on the block.
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*/
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#define ExternalChunkGetBlock(chunk) \
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(BumpBlock *) ((char *) chunk - Bump_BLOCKHDRSZ)
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/* Inlined helper functions */
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static inline void BumpBlockInit(BumpContext *context, BumpBlock *block,
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Size blksize);
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static inline bool BumpBlockIsEmpty(BumpBlock *block);
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static inline void BumpBlockMarkEmpty(BumpBlock *block);
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static inline Size BumpBlockFreeBytes(BumpBlock *block);
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static inline void BumpBlockFree(BumpContext *set, BumpBlock *block);
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/*
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* BumpContextCreate
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* Create a new Bump context.
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*
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* parent: parent context, or NULL if top-level context
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* name: name of context (must be statically allocated)
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* minContextSize: minimum context size
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* initBlockSize: initial allocation block size
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* maxBlockSize: maximum allocation block size
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*/
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MemoryContext
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BumpContextCreate(MemoryContext parent, const char *name, Size minContextSize,
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Size initBlockSize, Size maxBlockSize)
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{
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Size firstBlockSize;
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Size allocSize;
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BumpContext *set;
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BumpBlock *block;
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/* ensure MemoryChunk's size is properly maxaligned */
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StaticAssertDecl(Bump_CHUNKHDRSZ == MAXALIGN(Bump_CHUNKHDRSZ),
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"sizeof(MemoryChunk) is not maxaligned");
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/*
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* First, validate allocation parameters. Asserts seem sufficient because
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* nobody varies their parameters at runtime. We somewhat arbitrarily
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* enforce a minimum 1K block size. We restrict the maximum block size to
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* MEMORYCHUNK_MAX_BLOCKOFFSET as MemoryChunks are limited to this in
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* regards to addressing the offset between the chunk and the block that
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* the chunk is stored on. We would be unable to store the offset between
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* the chunk and block for any chunks that were beyond
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* MEMORYCHUNK_MAX_BLOCKOFFSET bytes into the block if the block was to be
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* larger than this.
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*/
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Assert(initBlockSize == MAXALIGN(initBlockSize) &&
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initBlockSize >= 1024);
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Assert(maxBlockSize == MAXALIGN(maxBlockSize) &&
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maxBlockSize >= initBlockSize &&
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AllocHugeSizeIsValid(maxBlockSize)); /* must be safe to double */
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Assert(minContextSize == 0 ||
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(minContextSize == MAXALIGN(minContextSize) &&
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minContextSize >= 1024 &&
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minContextSize <= maxBlockSize));
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Assert(maxBlockSize <= MEMORYCHUNK_MAX_BLOCKOFFSET);
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/* Determine size of initial block */
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allocSize = MAXALIGN(sizeof(BumpContext)) + Bump_BLOCKHDRSZ +
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Bump_CHUNKHDRSZ;
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if (minContextSize != 0)
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allocSize = Max(allocSize, minContextSize);
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else
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allocSize = Max(allocSize, initBlockSize);
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/*
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* Allocate the initial block. Unlike other bump.c blocks, it starts with
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* the context header and its block header follows that.
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*/
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set = (BumpContext *) malloc(allocSize);
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if (set == NULL)
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{
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MemoryContextStats(TopMemoryContext);
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ereport(ERROR,
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(errcode(ERRCODE_OUT_OF_MEMORY),
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errmsg("out of memory"),
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errdetail("Failed while creating memory context \"%s\".",
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name)));
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}
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/*
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* Avoid writing code that can fail between here and MemoryContextCreate;
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* we'd leak the header and initial block if we ereport in this stretch.
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*/
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dlist_init(&set->blocks);
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/* Fill in the initial block's block header */
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block = (BumpBlock *) (((char *) set) + MAXALIGN(sizeof(BumpContext)));
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/* determine the block size and initialize it */
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firstBlockSize = allocSize - MAXALIGN(sizeof(BumpContext));
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BumpBlockInit(set, block, firstBlockSize);
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/* add it to the doubly-linked list of blocks */
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dlist_push_head(&set->blocks, &block->node);
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/*
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* Fill in BumpContext-specific header fields. The Asserts above should
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* ensure that these all fit inside a uint32.
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*/
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set->initBlockSize = (uint32) initBlockSize;
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set->maxBlockSize = (uint32) maxBlockSize;
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set->nextBlockSize = (uint32) initBlockSize;
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/*
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* Compute the allocation chunk size limit for this context.
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*
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* Limit the maximum size a non-dedicated chunk can be so that we can fit
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* at least Bump_CHUNK_FRACTION of chunks this big onto the maximum sized
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* block. We must further limit this value so that it's no more than
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* MEMORYCHUNK_MAX_VALUE. We're unable to have non-external chunks larger
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* than that value as we store the chunk size in the MemoryChunk 'value'
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* field in the call to MemoryChunkSetHdrMask().
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*/
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set->allocChunkLimit = Min(maxBlockSize, MEMORYCHUNK_MAX_VALUE);
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while ((Size) (set->allocChunkLimit + Bump_CHUNKHDRSZ) >
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(Size) ((Size) (maxBlockSize - Bump_BLOCKHDRSZ) / Bump_CHUNK_FRACTION))
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set->allocChunkLimit >>= 1;
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/* Finally, do the type-independent part of context creation */
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MemoryContextCreate((MemoryContext) set, T_BumpContext, MCTX_BUMP_ID,
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parent, name);
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((MemoryContext) set)->mem_allocated = allocSize;
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return (MemoryContext) set;
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}
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/*
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* BumpReset
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* Frees all memory which is allocated in the given set.
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*
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* The code simply frees all the blocks in the context apart from the keeper
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* block.
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*/
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void
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BumpReset(MemoryContext context)
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{
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BumpContext *set = (BumpContext *) context;
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dlist_mutable_iter miter;
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Assert(BumpIsValid(set));
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#ifdef MEMORY_CONTEXT_CHECKING
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/* Check for corruption and leaks before freeing */
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BumpCheck(context);
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#endif
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dlist_foreach_modify(miter, &set->blocks)
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{
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BumpBlock *block = dlist_container(BumpBlock, node, miter.cur);
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if (IsKeeperBlock(set, block))
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BumpBlockMarkEmpty(block);
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else
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BumpBlockFree(set, block);
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}
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/* Reset block size allocation sequence, too */
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set->nextBlockSize = set->initBlockSize;
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/* Ensure there is only 1 item in the dlist */
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Assert(!dlist_is_empty(&set->blocks));
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Assert(!dlist_has_next(&set->blocks, dlist_head_node(&set->blocks)));
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}
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/*
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* BumpDelete
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* Free all memory which is allocated in the given context.
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*/
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void
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BumpDelete(MemoryContext context)
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{
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/* Reset to release all releasable BumpBlocks */
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BumpReset(context);
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/* And free the context header and keeper block */
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free(context);
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}
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/*
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* Helper for BumpAlloc() that allocates an entire block for the chunk.
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*
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* BumpAlloc()'s comment explains why this is separate.
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*/
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pg_noinline
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static void *
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BumpAllocLarge(MemoryContext context, Size size, int flags)
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{
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BumpContext *set = (BumpContext *) context;
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BumpBlock *block;
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#ifdef MEMORY_CONTEXT_CHECKING
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MemoryChunk *chunk;
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#endif
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Size chunk_size;
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Size required_size;
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Size blksize;
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/* validate 'size' is within the limits for the given 'flags' */
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MemoryContextCheckSize(context, size, flags);
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#ifdef MEMORY_CONTEXT_CHECKING
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/* ensure there's always space for the sentinel byte */
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chunk_size = MAXALIGN(size + 1);
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#else
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chunk_size = MAXALIGN(size);
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#endif
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required_size = chunk_size + Bump_CHUNKHDRSZ;
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blksize = required_size + Bump_BLOCKHDRSZ;
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block = (BumpBlock *) malloc(blksize);
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if (block == NULL)
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return NULL;
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context->mem_allocated += blksize;
|
|
|
|
|
|
|
|
|
|
/* the block is completely full */
|
|
|
|
|
block->freeptr = block->endptr = ((char *) block) + blksize;
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
/* block with a single (used) chunk */
|
|
|
|
|
block->context = set;
|
|
|
|
|
|
|
|
|
|
chunk = (MemoryChunk *) (((char *) block) + Bump_BLOCKHDRSZ);
|
|
|
|
|
|
|
|
|
|
/* mark the MemoryChunk as externally managed */
|
|
|
|
|
MemoryChunkSetHdrMaskExternal(chunk, MCTX_BUMP_ID);
|
|
|
|
|
|
|
|
|
|
chunk->requested_size = size;
|
|
|
|
|
/* set mark to catch clobber of "unused" space */
|
|
|
|
|
Assert(size < chunk_size);
|
|
|
|
|
set_sentinel(MemoryChunkGetPointer(chunk), size);
|
|
|
|
|
#endif
|
|
|
|
|
#ifdef RANDOMIZE_ALLOCATED_MEMORY
|
|
|
|
|
/* fill the allocated space with junk */
|
|
|
|
|
randomize_mem((char *) MemoryChunkGetPointer(chunk), size);
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* add the block to the list of allocated blocks */
|
|
|
|
|
dlist_push_head(&set->blocks, &block->node);
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
/* Ensure any padding bytes are marked NOACCESS. */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS((char *) MemoryChunkGetPointer(chunk) + size,
|
|
|
|
|
chunk_size - size);
|
|
|
|
|
|
|
|
|
|
/* Disallow access to the chunk header. */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS(chunk, Bump_CHUNKHDRSZ);
|
|
|
|
|
|
|
|
|
|
return MemoryChunkGetPointer(chunk);
|
|
|
|
|
#else
|
|
|
|
|
return (void *) (((char *) block) + Bump_BLOCKHDRSZ);
|
|
|
|
|
#endif
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Small helper for allocating a new chunk from a chunk, to avoid duplicating
|
|
|
|
|
* the code between BumpAlloc() and BumpAllocFromNewBlock().
|
|
|
|
|
*/
|
|
|
|
|
static inline void *
|
|
|
|
|
BumpAllocChunkFromBlock(MemoryContext context, BumpBlock *block, Size size,
|
|
|
|
|
Size chunk_size)
|
|
|
|
|
{
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
MemoryChunk *chunk;
|
|
|
|
|
#else
|
|
|
|
|
void *ptr;
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* validate we've been given a block with enough free space */
|
|
|
|
|
Assert(block != NULL);
|
|
|
|
|
Assert((block->endptr - block->freeptr) >= Bump_CHUNKHDRSZ + chunk_size);
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
chunk = (MemoryChunk *) block->freeptr;
|
|
|
|
|
#else
|
|
|
|
|
ptr = (void *) block->freeptr;
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* point the freeptr beyond this chunk */
|
|
|
|
|
block->freeptr += (Bump_CHUNKHDRSZ + chunk_size);
|
|
|
|
|
Assert(block->freeptr <= block->endptr);
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
/* Prepare to initialize the chunk header. */
|
|
|
|
|
VALGRIND_MAKE_MEM_UNDEFINED(chunk, Bump_CHUNKHDRSZ);
|
|
|
|
|
|
|
|
|
|
MemoryChunkSetHdrMask(chunk, block, chunk_size, MCTX_BUMP_ID);
|
|
|
|
|
chunk->requested_size = size;
|
|
|
|
|
/* set mark to catch clobber of "unused" space */
|
|
|
|
|
Assert(size < chunk_size);
|
|
|
|
|
set_sentinel(MemoryChunkGetPointer(chunk), size);
|
|
|
|
|
|
|
|
|
|
#ifdef RANDOMIZE_ALLOCATED_MEMORY
|
|
|
|
|
/* fill the allocated space with junk */
|
|
|
|
|
randomize_mem((char *) MemoryChunkGetPointer(chunk), size);
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* Ensure any padding bytes are marked NOACCESS. */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS((char *) MemoryChunkGetPointer(chunk) + size,
|
|
|
|
|
chunk_size - size);
|
|
|
|
|
|
|
|
|
|
/* Disallow access to the chunk header. */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS(chunk, Bump_CHUNKHDRSZ);
|
|
|
|
|
|
|
|
|
|
return MemoryChunkGetPointer(chunk);
|
|
|
|
|
#else
|
|
|
|
|
return ptr;
|
|
|
|
|
#endif /* MEMORY_CONTEXT_CHECKING */
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Helper for BumpAlloc() that allocates a new block and returns a chunk
|
|
|
|
|
* allocated from it.
|
|
|
|
|
*
|
|
|
|
|
* BumpAlloc()'s comment explains why this is separate.
|
|
|
|
|
*/
|
|
|
|
|
pg_noinline
|
|
|
|
|
static void *
|
|
|
|
|
BumpAllocFromNewBlock(MemoryContext context, Size size, int flags,
|
|
|
|
|
Size chunk_size)
|
|
|
|
|
{
|
|
|
|
|
BumpContext *set = (BumpContext *) context;
|
|
|
|
|
BumpBlock *block;
|
|
|
|
|
Size blksize;
|
|
|
|
|
Size required_size;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* The first such block has size initBlockSize, and we double the space in
|
|
|
|
|
* each succeeding block, but not more than maxBlockSize.
|
|
|
|
|
*/
|
|
|
|
|
blksize = set->nextBlockSize;
|
|
|
|
|
set->nextBlockSize <<= 1;
|
|
|
|
|
if (set->nextBlockSize > set->maxBlockSize)
|
|
|
|
|
set->nextBlockSize = set->maxBlockSize;
|
|
|
|
|
|
|
|
|
|
/* we'll need space for the chunk, chunk hdr and block hdr */
|
|
|
|
|
required_size = chunk_size + Bump_CHUNKHDRSZ + Bump_BLOCKHDRSZ;
|
|
|
|
|
/* round the size up to the next power of 2 */
|
|
|
|
|
if (blksize < required_size)
|
|
|
|
|
blksize = pg_nextpower2_size_t(required_size);
|
|
|
|
|
|
|
|
|
|
block = (BumpBlock *) malloc(blksize);
|
|
|
|
|
|
|
|
|
|
if (block == NULL)
|
|
|
|
|
return MemoryContextAllocationFailure(context, size, flags);
|
|
|
|
|
|
|
|
|
|
context->mem_allocated += blksize;
|
|
|
|
|
|
|
|
|
|
/* initialize the new block */
|
|
|
|
|
BumpBlockInit(set, block, blksize);
|
|
|
|
|
|
|
|
|
|
/* add it to the doubly-linked list of blocks */
|
|
|
|
|
dlist_push_head(&set->blocks, &block->node);
|
|
|
|
|
|
|
|
|
|
return BumpAllocChunkFromBlock(context, block, size, chunk_size);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpAlloc
|
|
|
|
|
* Returns a pointer to allocated memory of given size or raises an ERROR
|
|
|
|
|
* on allocation failure, or returns NULL when flags contains
|
|
|
|
|
* MCXT_ALLOC_NO_OOM.
|
|
|
|
|
*
|
|
|
|
|
* No request may exceed:
|
|
|
|
|
* MAXALIGN_DOWN(SIZE_MAX) - Bump_BLOCKHDRSZ - Bump_CHUNKHDRSZ
|
|
|
|
|
* All callers use a much-lower limit.
|
|
|
|
|
*
|
|
|
|
|
*
|
|
|
|
|
* Note: when using valgrind, it doesn't matter how the returned allocation
|
|
|
|
|
* is marked, as mcxt.c will set it to UNDEFINED.
|
|
|
|
|
* This function should only contain the most common code paths. Everything
|
|
|
|
|
* else should be in pg_noinline helper functions, thus avoiding the overhead
|
|
|
|
|
* of creating a stack frame for the common cases. Allocating memory is often
|
|
|
|
|
* a bottleneck in many workloads, so avoiding stack frame setup is
|
|
|
|
|
* worthwhile. Helper functions should always directly return the newly
|
|
|
|
|
* allocated memory so that we can just return that address directly as a tail
|
|
|
|
|
* call.
|
|
|
|
|
*/
|
|
|
|
|
void *
|
|
|
|
|
BumpAlloc(MemoryContext context, Size size, int flags)
|
|
|
|
|
{
|
|
|
|
|
BumpContext *set = (BumpContext *) context;
|
|
|
|
|
BumpBlock *block;
|
|
|
|
|
Size chunk_size;
|
|
|
|
|
Size required_size;
|
|
|
|
|
|
|
|
|
|
Assert(BumpIsValid(set));
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
/* ensure there's always space for the sentinel byte */
|
|
|
|
|
chunk_size = MAXALIGN(size + 1);
|
|
|
|
|
#else
|
|
|
|
|
chunk_size = MAXALIGN(size);
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* If requested size exceeds maximum for chunks we hand the the request
|
|
|
|
|
* off to BumpAllocLarge().
|
|
|
|
|
*/
|
|
|
|
|
if (chunk_size > set->allocChunkLimit)
|
|
|
|
|
return BumpAllocLarge(context, size, flags);
|
|
|
|
|
|
|
|
|
|
required_size = chunk_size + Bump_CHUNKHDRSZ;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Not an oversized chunk. We try to first make use of the latest block,
|
|
|
|
|
* but if there's not enough space in it we must allocate a new block.
|
|
|
|
|
*/
|
|
|
|
|
block = dlist_container(BumpBlock, node, dlist_head_node(&set->blocks));
|
|
|
|
|
|
|
|
|
|
if (BumpBlockFreeBytes(block) < required_size)
|
|
|
|
|
return BumpAllocFromNewBlock(context, size, flags, chunk_size);
|
|
|
|
|
|
|
|
|
|
/* The current block has space, so just allocate chunk there. */
|
|
|
|
|
return BumpAllocChunkFromBlock(context, block, size, chunk_size);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpBlockInit
|
|
|
|
|
* Initializes 'block' assuming 'blksize'. Does not update the context's
|
|
|
|
|
* mem_allocated field.
|
|
|
|
|
*/
|
|
|
|
|
static inline void
|
|
|
|
|
BumpBlockInit(BumpContext *context, BumpBlock *block, Size blksize)
|
|
|
|
|
{
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
block->context = context;
|
|
|
|
|
#endif
|
|
|
|
|
block->freeptr = ((char *) block) + Bump_BLOCKHDRSZ;
|
|
|
|
|
block->endptr = ((char *) block) + blksize;
|
|
|
|
|
|
|
|
|
|
/* Mark unallocated space NOACCESS. */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS(block->freeptr, blksize - Bump_BLOCKHDRSZ);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpBlockIsEmpty
|
|
|
|
|
* Returns true iff 'block' contains no chunks
|
|
|
|
|
*/
|
|
|
|
|
static inline bool
|
|
|
|
|
BumpBlockIsEmpty(BumpBlock *block)
|
|
|
|
|
{
|
|
|
|
|
/* it's empty if the freeptr has not moved */
|
|
|
|
|
return (block->freeptr == ((char *) block + Bump_BLOCKHDRSZ));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpBlockMarkEmpty
|
|
|
|
|
* Set a block as empty. Does not free the block.
|
|
|
|
|
*/
|
|
|
|
|
static inline void
|
|
|
|
|
BumpBlockMarkEmpty(BumpBlock *block)
|
|
|
|
|
{
|
|
|
|
|
#if defined(USE_VALGRIND) || defined(CLOBBER_FREED_MEMORY)
|
|
|
|
|
char *datastart = ((char *) block) + Bump_BLOCKHDRSZ;
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
#ifdef CLOBBER_FREED_MEMORY
|
|
|
|
|
wipe_mem(datastart, block->freeptr - datastart);
|
|
|
|
|
#else
|
|
|
|
|
/* wipe_mem() would have done this */
|
|
|
|
|
VALGRIND_MAKE_MEM_NOACCESS(datastart, block->freeptr - datastart);
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/* Reset the block, but don't return it to malloc */
|
|
|
|
|
block->freeptr = ((char *) block) + Bump_BLOCKHDRSZ;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpBlockFreeBytes
|
|
|
|
|
* Returns the number of bytes free in 'block'
|
|
|
|
|
*/
|
|
|
|
|
static inline Size
|
|
|
|
|
BumpBlockFreeBytes(BumpBlock *block)
|
|
|
|
|
{
|
|
|
|
|
return (block->endptr - block->freeptr);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpBlockFree
|
|
|
|
|
* Remove 'block' from 'set' and release the memory consumed by it.
|
|
|
|
|
*/
|
|
|
|
|
static inline void
|
|
|
|
|
BumpBlockFree(BumpContext *set, BumpBlock *block)
|
|
|
|
|
{
|
|
|
|
|
/* Make sure nobody tries to free the keeper block */
|
|
|
|
|
Assert(!IsKeeperBlock(set, block));
|
|
|
|
|
|
|
|
|
|
/* release the block from the list of blocks */
|
|
|
|
|
dlist_delete(&block->node);
|
|
|
|
|
|
|
|
|
|
((MemoryContext) set)->mem_allocated -= ((char *) block->endptr - (char *) block);
|
|
|
|
|
|
|
|
|
|
#ifdef CLOBBER_FREED_MEMORY
|
|
|
|
|
wipe_mem(block, ((char *) block->endptr - (char *) block));
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
free(block);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpFree
|
|
|
|
|
* Unsupported.
|
|
|
|
|
*/
|
|
|
|
|
void
|
|
|
|
|
BumpFree(void *pointer)
|
|
|
|
|
{
|
|
|
|
|
elog(ERROR, "pfree is not supported by the bump memory allocator");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpRealloc
|
|
|
|
|
* Unsupported.
|
|
|
|
|
*/
|
|
|
|
|
void *
|
|
|
|
|
BumpRealloc(void *pointer, Size size, int flags)
|
|
|
|
|
{
|
|
|
|
|
elog(ERROR, "%s is not supported by the bump memory allocator", "realloc");
|
|
|
|
|
return NULL; /* keep compiler quiet */
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpGetChunkContext
|
|
|
|
|
* Unsupported.
|
|
|
|
|
*/
|
|
|
|
|
MemoryContext
|
|
|
|
|
BumpGetChunkContext(void *pointer)
|
|
|
|
|
{
|
|
|
|
|
elog(ERROR, "%s is not supported by the bump memory allocator", "GetMemoryChunkContext");
|
|
|
|
|
return NULL; /* keep compiler quiet */
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpGetChunkSpace
|
|
|
|
|
* Given a currently-allocated chunk, determine the total space
|
|
|
|
|
* it occupies (including all memory-allocation overhead).
|
|
|
|
|
*/
|
|
|
|
|
Size
|
|
|
|
|
BumpGetChunkSpace(void *pointer)
|
|
|
|
|
{
|
|
|
|
|
elog(ERROR, "%s is not supported by the bump memory allocator", "GetMemoryChunkSpace");
|
|
|
|
|
return 0; /* keep compiler quiet */
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpIsEmpty
|
|
|
|
|
* Is a BumpContext empty of any allocated space?
|
|
|
|
|
*/
|
|
|
|
|
bool
|
|
|
|
|
BumpIsEmpty(MemoryContext context)
|
|
|
|
|
{
|
|
|
|
|
BumpContext *set = (BumpContext *) context;
|
|
|
|
|
dlist_iter iter;
|
|
|
|
|
|
|
|
|
|
Assert(BumpIsValid(set));
|
|
|
|
|
|
|
|
|
|
dlist_foreach(iter, &set->blocks)
|
|
|
|
|
{
|
|
|
|
|
BumpBlock *block = dlist_container(BumpBlock, node, iter.cur);
|
|
|
|
|
|
|
|
|
|
if (!BumpBlockIsEmpty(block))
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpStats
|
|
|
|
|
* Compute stats about memory consumption of a Bump context.
|
|
|
|
|
*
|
|
|
|
|
* printfunc: if not NULL, pass a human-readable stats string to this.
|
|
|
|
|
* passthru: pass this pointer through to printfunc.
|
|
|
|
|
* totals: if not NULL, add stats about this context into *totals.
|
|
|
|
|
* print_to_stderr: print stats to stderr if true, elog otherwise.
|
|
|
|
|
*/
|
|
|
|
|
void
|
|
|
|
|
BumpStats(MemoryContext context, MemoryStatsPrintFunc printfunc,
|
|
|
|
|
void *passthru, MemoryContextCounters *totals, bool print_to_stderr)
|
|
|
|
|
{
|
|
|
|
|
BumpContext *set = (BumpContext *) context;
|
|
|
|
|
Size nblocks = 0;
|
|
|
|
|
Size totalspace = 0;
|
|
|
|
|
Size freespace = 0;
|
|
|
|
|
dlist_iter iter;
|
|
|
|
|
|
|
|
|
|
Assert(BumpIsValid(set));
|
|
|
|
|
|
|
|
|
|
dlist_foreach(iter, &set->blocks)
|
|
|
|
|
{
|
|
|
|
|
BumpBlock *block = dlist_container(BumpBlock, node, iter.cur);
|
|
|
|
|
|
|
|
|
|
nblocks++;
|
|
|
|
|
totalspace += (block->endptr - (char *) block);
|
|
|
|
|
freespace += (block->endptr - block->freeptr);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (printfunc)
|
|
|
|
|
{
|
|
|
|
|
char stats_string[200];
|
|
|
|
|
|
|
|
|
|
snprintf(stats_string, sizeof(stats_string),
|
|
|
|
|
"%zu total in %zu blocks; %zu free; %zu used",
|
|
|
|
|
totalspace, nblocks, freespace, totalspace - freespace);
|
|
|
|
|
printfunc(context, passthru, stats_string, print_to_stderr);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (totals)
|
|
|
|
|
{
|
|
|
|
|
totals->nblocks += nblocks;
|
|
|
|
|
totals->totalspace += totalspace;
|
|
|
|
|
totals->freespace += freespace;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
#ifdef MEMORY_CONTEXT_CHECKING
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* BumpCheck
|
|
|
|
|
* Walk through chunks and check consistency of memory.
|
|
|
|
|
*
|
|
|
|
|
* NOTE: report errors as WARNING, *not* ERROR or FATAL. Otherwise you'll
|
|
|
|
|
* find yourself in an infinite loop when trouble occurs, because this
|
|
|
|
|
* routine will be entered again when elog cleanup tries to release memory!
|
|
|
|
|
*/
|
|
|
|
|
void
|
|
|
|
|
BumpCheck(MemoryContext context)
|
|
|
|
|
{
|
|
|
|
|
BumpContext *bump = (BumpContext *) context;
|
|
|
|
|
const char *name = context->name;
|
|
|
|
|
dlist_iter iter;
|
|
|
|
|
Size total_allocated = 0;
|
|
|
|
|
|
|
|
|
|
/* walk all blocks in this context */
|
|
|
|
|
dlist_foreach(iter, &bump->blocks)
|
|
|
|
|
{
|
|
|
|
|
BumpBlock *block = dlist_container(BumpBlock, node, iter.cur);
|
|
|
|
|
int nchunks;
|
|
|
|
|
char *ptr;
|
|
|
|
|
bool has_external_chunk = false;
|
|
|
|
|
|
|
|
|
|
if (IsKeeperBlock(bump, block))
|
|
|
|
|
total_allocated += block->endptr - (char *) bump;
|
|
|
|
|
else
|
|
|
|
|
total_allocated += block->endptr - (char *) block;
|
|
|
|
|
|
|
|
|
|
/* check block belongs to the correct context */
|
|
|
|
|
if (block->context != bump)
|
|
|
|
|
elog(WARNING, "problem in Bump %s: bogus context link in block %p",
|
|
|
|
|
name, block);
|
|
|
|
|
|
|
|
|
|
/* now walk through the chunks and count them */
|
|
|
|
|
nchunks = 0;
|
|
|
|
|
ptr = ((char *) block) + Bump_BLOCKHDRSZ;
|
|
|
|
|
|
|
|
|
|
while (ptr < block->freeptr)
|
|
|
|
|
{
|
|
|
|
|
MemoryChunk *chunk = (MemoryChunk *) ptr;
|
|
|
|
|
BumpBlock *chunkblock;
|
|
|
|
|
Size chunksize;
|
|
|
|
|
|
|
|
|
|
/* allow access to the chunk header */
|
|
|
|
|
VALGRIND_MAKE_MEM_DEFINED(chunk, Bump_CHUNKHDRSZ);
|
|
|
|
|
|
|
|
|
|
if (MemoryChunkIsExternal(chunk))
|
|
|
|
|
{
|
|
|
|
|
chunkblock = ExternalChunkGetBlock(chunk);
|
|
|
|
|
chunksize = block->endptr - (char *) MemoryChunkGetPointer(chunk);
|
|
|
|
|
has_external_chunk = true;
|
|
|
|
|
}
|
|
|
|
|
else
|
|
|
|
|
{
|
|
|
|
|
chunkblock = MemoryChunkGetBlock(chunk);
|
|
|
|
|
chunksize = MemoryChunkGetValue(chunk);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* move to the next chunk */
|
|
|
|
|
ptr += (chunksize + Bump_CHUNKHDRSZ);
|
|
|
|
|
|
|
|
|
|
nchunks += 1;
|
|
|
|
|
|
|
|
|
|
/* chunks have both block and context pointers, so check both */
|
|
|
|
|
if (chunkblock != block)
|
|
|
|
|
elog(WARNING, "problem in Bump %s: bogus block link in block %p, chunk %p",
|
|
|
|
|
name, block, chunk);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (has_external_chunk && nchunks > 1)
|
|
|
|
|
elog(WARNING, "problem in Bump %s: external chunk on non-dedicated block %p",
|
|
|
|
|
name, block);
|
|
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
Assert(total_allocated == context->mem_allocated);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#endif /* MEMORY_CONTEXT_CHECKING */
|