From 8fb8e3f63654df20926f665486d2edea2fff0243 Mon Sep 17 00:00:00 2001 From: Jameson Miller Date: Mon, 2 Jul 2018 19:49:33 +0000 Subject: mem-pool: only search head block for available space Instead of searching all memory blocks for available space to fulfill a memory request, only search the head block. If the head block does not have space, assume that previous block would most likely not be able to fulfill request either. This could potentially lead to more memory fragmentation, but also avoids searching memory blocks that probably will not be able to fulfill request. This pattern will benefit consumers that are able to generate a good estimate for how much memory will be needed, or if they are performing fixed sized allocations, so that once a block is exhausted it will never be able to fulfill a future request. Signed-off-by: Jameson Miller Signed-off-by: Junio C Hamano --- mem-pool.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mem-pool.c b/mem-pool.c index 389d7af447..c80124f1fe 100644 --- a/mem-pool.c +++ b/mem-pool.c @@ -21,16 +21,16 @@ static struct mp_block *mem_pool_alloc_block(struct mem_pool *mem_pool, size_t b void *mem_pool_alloc(struct mem_pool *mem_pool, size_t len) { - struct mp_block *p; + struct mp_block *p = NULL; void *r; /* round up to a 'uintmax_t' alignment */ if (len & (sizeof(uintmax_t) - 1)) len += sizeof(uintmax_t) - (len & (sizeof(uintmax_t) - 1)); - for (p = mem_pool->mp_block; p; p = p->next_block) - if (p->end - p->next_free >= len) - break; + if (mem_pool->mp_block && + mem_pool->mp_block->end - mem_pool->mp_block->next_free >= len) + p = mem_pool->mp_block; if (!p) { if (len >= (mem_pool->block_alloc / 2)) { -- cgit v1.2.3