diff options
Diffstat (limited to 'src/backend/utils/mmgr/mcxt.c')
| -rw-r--r-- | src/backend/utils/mmgr/mcxt.c | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c index e83e76dc0f3..4185a03e9ff 100644 --- a/src/backend/utils/mmgr/mcxt.c +++ b/src/backend/utils/mmgr/mcxt.c @@ -60,15 +60,9 @@ static void MemoryContextStatsInternal(MemoryContext context, int level); * You should not do memory allocations within a critical section, because * an out-of-memory error will be escalated to a PANIC. To enforce that * rule, the allocation functions Assert that. - * - * There are a two exceptions: 1) error recovery uses ErrorContext, which - * has some memory set aside so that you don't run out. And 2) checkpointer - * currently just hopes for the best, which is wrong and ought to be fixed, - * but it's a known issue so let's not complain about in the meanwhile. */ #define AssertNotInCriticalSection(context) \ - Assert(CritSectionCount == 0 || (context) == ErrorContext || \ - AmCheckpointerProcess()) + Assert(CritSectionCount == 0 || (context)->allowInCritSection) /***************************************************************************** * EXPORTED ROUTINES * @@ -120,7 +114,10 @@ MemoryContextInit(void) * require it to contain at least 8K at all times. This is the only case * where retained memory in a context is *essential* --- we want to be * sure ErrorContext still has some memory even if we've run out - * elsewhere! + * elsewhere! Also, allow allocations in ErrorContext within a critical + * section. Otherwise a PANIC will cause an assertion failure in the + * error reporting code, before printing out the real cause of the + * failure. * * This should be the last step in this function, as elog.c assumes memory * management works once ErrorContext is non-null. @@ -130,6 +127,7 @@ MemoryContextInit(void) 8 * 1024, 8 * 1024, 8 * 1024); + MemoryContextAllowInCriticalSection(ErrorContext, true); } /* @@ -306,6 +304,26 @@ MemoryContextSetParent(MemoryContext context, MemoryContext new_parent) } /* + * MemoryContextAllowInCriticalSection + * Allow/disallow allocations in this memory context within a critical + * section. + * + * Normally, memory allocations are not allowed within a critical section, + * because a failure would lead to PANIC. There are a few exceptions to + * that, like allocations related to debugging code that is not supposed to + * be enabled in production. This function can be used to exempt specific + * memory contexts from the assertion in palloc(). + */ +void +MemoryContextAllowInCriticalSection(MemoryContext context, bool allow) +{ + AssertArg(MemoryContextIsValid(context)); +#ifdef USE_ASSERT_CHECKING + context->allowInCritSection = allow; +#endif +} + +/* * GetMemoryChunkSpace * Given a currently-allocated chunk, determine the total space * it occupies (including all memory-allocation overhead). @@ -533,6 +551,7 @@ MemoryContextCreate(NodeTag tag, Size size, MemoryContext node; Size needed = size + strlen(name) + 1; + /* creating new memory contexts is not allowed in a critical section */ Assert(CritSectionCount == 0); /* Get space for node and name */ @@ -570,6 +589,11 @@ MemoryContextCreate(NodeTag tag, Size size, node->parent = parent; node->nextchild = parent->firstchild; parent->firstchild = node; + +#ifdef USE_ASSERT_CHECKING + /* inherit allowInCritSection flag from parent */ + node->allowInCritSection = parent->allowInCritSection; +#endif } VALGRIND_CREATE_MEMPOOL(node, 0, false); |