commit ecaef8ecf5705b9638f81d2dfb300b57589fbb8a Author: Tom Lane Date: Mon Sep 5 16:14:41 2022 -0400 Preliminary improvements in memory-context infrastructure. We lack a version of repalloc() that supports MCXT_ALLOC_NO_OOM semantics, so invent repalloc_extended(). repalloc_huge() becomes a legacy wrapper for that. Also, fix dynahash.c so that it can support HASH_ENTER_NULL requests when using the default palloc-based allocator. The only reason it was like that was the lack of the MCXT_ALLOC_NO_OOM option when that code was written, ages ago. While here, simplify a few overcomplicated tests in mcxt.c. diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c index 3babde8d70..4f62958883 100644 --- a/src/backend/utils/hash/dynahash.c +++ b/src/backend/utils/hash/dynahash.c @@ -289,7 +289,8 @@ static void * DynaHashAlloc(Size size) { Assert(MemoryContextIsValid(CurrentDynaHashCxt)); - return MemoryContextAlloc(CurrentDynaHashCxt, size); + return MemoryContextAllocExtended(CurrentDynaHashCxt, size, + MCXT_ALLOC_NO_OOM); } @@ -939,9 +940,7 @@ calc_bucket(HASHHDR *hctl, uint32 hash_val) * * HASH_ENTER will normally ereport a generic "out of memory" error if * it is unable to create a new entry. The HASH_ENTER_NULL operation is - * the same except it will return NULL if out of memory. Note that - * HASH_ENTER_NULL cannot be used with the default palloc-based allocator, - * since palloc internally ereports on out-of-memory. + * the same except it will return NULL if out of memory. * * If foundPtr isn't NULL, then *foundPtr is set true if we found an * existing entry in the table, false otherwise. This is needed in the @@ -1084,12 +1083,8 @@ hash_search_with_hash_value(HTAB *hashp, } return NULL; - case HASH_ENTER_NULL: - /* ENTER_NULL does not work with palloc-based allocator */ - Assert(hashp->alloc != DynaHashAlloc); - /* FALL THRU */ - case HASH_ENTER: + case HASH_ENTER_NULL: /* Return existing element if found, else create one */ if (currBucket != NULL) return (void *) ELEMENTKEY(currBucket); diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c index 64bcc7ef32..5618944e4c 100644 --- a/src/backend/utils/mmgr/mcxt.c +++ b/src/backend/utils/mmgr/mcxt.c @@ -1044,8 +1044,8 @@ MemoryContextAllocExtended(MemoryContext context, Size size, int flags) AssertArg(MemoryContextIsValid(context)); AssertNotInCriticalSection(context); - if (((flags & MCXT_ALLOC_HUGE) != 0 && !AllocHugeSizeIsValid(size)) || - ((flags & MCXT_ALLOC_HUGE) == 0 && !AllocSizeIsValid(size))) + if (!((flags & MCXT_ALLOC_HUGE) != 0 ? AllocHugeSizeIsValid(size) : + AllocSizeIsValid(size))) elog(ERROR, "invalid memory alloc request size %zu", size); context->isReset = false; @@ -1199,8 +1199,8 @@ palloc_extended(Size size, int flags) AssertArg(MemoryContextIsValid(context)); AssertNotInCriticalSection(context); - if (((flags & MCXT_ALLOC_HUGE) != 0 && !AllocHugeSizeIsValid(size)) || - ((flags & MCXT_ALLOC_HUGE) == 0 && !AllocSizeIsValid(size))) + if (!((flags & MCXT_ALLOC_HUGE) != 0 ? AllocHugeSizeIsValid(size) : + AllocSizeIsValid(size))) elog(ERROR, "invalid memory alloc request size %zu", size); context->isReset = false; @@ -1281,6 +1281,50 @@ repalloc(void *pointer, Size size) return ret; } +/* + * repalloc_extended + * Adjust the size of a previously allocated chunk, + * with HUGE and NO_OOM options. + */ +void * +repalloc_extended(void *pointer, Size size, int flags) +{ +#if defined(USE_ASSERT_CHECKING) || defined(USE_VALGRIND) + MemoryContext context = GetMemoryChunkContext(pointer); +#endif + void *ret; + + if (!((flags & MCXT_ALLOC_HUGE) != 0 ? AllocHugeSizeIsValid(size) : + AllocSizeIsValid(size))) + elog(ERROR, "invalid memory alloc request size %zu", size); + + AssertNotInCriticalSection(context); + + /* isReset must be false already */ + Assert(!context->isReset); + + ret = MCXT_METHOD(pointer, realloc) (pointer, size); + if (unlikely(ret == NULL)) + { + if ((flags & MCXT_ALLOC_NO_OOM) == 0) + { + MemoryContext cxt = GetMemoryChunkContext(pointer); + + MemoryContextStats(TopMemoryContext); + ereport(ERROR, + (errcode(ERRCODE_OUT_OF_MEMORY), + errmsg("out of memory"), + errdetail("Failed on request of size %zu in memory context \"%s\".", + size, cxt->name))); + } + return NULL; + } + + VALGRIND_MEMPOOL_CHANGE(context, pointer, ret, size); + + return ret; +} + /* * MemoryContextAllocHuge * Allocate (possibly-expansive) space within the specified context. @@ -1324,35 +1368,8 @@ MemoryContextAllocHuge(MemoryContext context, Size size) void * repalloc_huge(void *pointer, Size size) { -#if defined(USE_ASSERT_CHECKING) || defined(USE_VALGRIND) - MemoryContext context = GetMemoryChunkContext(pointer); -#endif - void *ret; - - if (!AllocHugeSizeIsValid(size)) - elog(ERROR, "invalid memory alloc request size %zu", size); - - AssertNotInCriticalSection(context); - - /* isReset must be false already */ - Assert(!context->isReset); - - ret = MCXT_METHOD(pointer, realloc) (pointer, size); - if (unlikely(ret == NULL)) - { - MemoryContext cxt = GetMemoryChunkContext(pointer); - - MemoryContextStats(TopMemoryContext); - ereport(ERROR, - (errcode(ERRCODE_OUT_OF_MEMORY), - errmsg("out of memory"), - errdetail("Failed on request of size %zu in memory context \"%s\".", - size, cxt->name))); - } - - VALGRIND_MEMPOOL_CHANGE(context, pointer, ret, size); - - return ret; + /* this one seems not worth its own implementation */ + return repalloc_extended(pointer, size, MCXT_ALLOC_HUGE); } /* diff --git a/src/include/utils/palloc.h b/src/include/utils/palloc.h index 332575f518..f31ab3d7af 100644 --- a/src/include/utils/palloc.h +++ b/src/include/utils/palloc.h @@ -78,6 +78,8 @@ extern void *palloc(Size size); extern void *palloc0(Size size); extern void *palloc_extended(Size size, int flags); extern pg_nodiscard void *repalloc(void *pointer, Size size); +extern pg_nodiscard void *repalloc_extended(void *pointer, + Size size, int flags); extern void pfree(void *pointer); /*