From: Benjamin LaHaise <bcrl@kvack.org>
Date: Thu, 23 Jun 2005 07:10:01 +0000 (-0700)
Subject: [PATCH] mempool - only init waitqueue in slow path
X-Git-Tag: v2.6.13-rc4~130^2~35
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=01890a4c120f68366441bf5e193d1b9dd543d4d0;p=linux.git

[PATCH] mempool - only init waitqueue in slow path

Here's a small patch to improve the performance of mempool_alloc by only
initializing the wait queue when we're about to wait.

Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/mm/mempool.c b/mm/mempool.c
index 920c8c3ab1b8..9a72f7d918fa 100644
--- a/mm/mempool.c
+++ b/mm/mempool.c
@@ -204,7 +204,7 @@ void * mempool_alloc(mempool_t *pool, unsigned int __nocast gfp_mask)
 {
 	void *element;
 	unsigned long flags;
-	DEFINE_WAIT(wait);
+	wait_queue_t wait;
 	int gfp_temp;
 
 	might_sleep_if(gfp_mask & __GFP_WAIT);
@@ -235,6 +235,7 @@ void * mempool_alloc(mempool_t *pool, unsigned int __nocast gfp_mask)
 
 	/* Now start performing page reclaim */
 	gfp_temp = gfp_mask;
+	init_wait(&wait);
 	prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
 	smp_mb();
 	if (!pool->curr_nr)