From: Brian Behlendorf <behlendorf1@llnl.gov>
Date: Thu, 26 Aug 2010 18:00:46 +0000 (-0700)
Subject: Fix stack vdev_cache_read()
X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=commitdiff_plain;h=5fed499defe68b57fab349ac945a84416fb024ba;hp=47050a88ac1445f3557030d0d7e61b8a397a5476;p=zfs.git

Fix stack vdev_cache_read()

Moving the vdev_cache_entry_t struct ve_search from the stack to
the heap saves ~100 bytes.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
---

diff --git a/module/zfs/vdev_cache.c b/module/zfs/vdev_cache.c
index a4b3442..c5439ba 100644
--- a/module/zfs/vdev_cache.c
+++ b/module/zfs/vdev_cache.c
@@ -244,7 +244,7 @@ int
 vdev_cache_read(zio_t *zio)
 {
 	vdev_cache_t *vc = &zio->io_vd->vdev_cache;
-	vdev_cache_entry_t *ve, ve_search;
+	vdev_cache_entry_t *ve, *ve_search;
 	uint64_t cache_offset = P2ALIGN(zio->io_offset, VCBS);
 	ASSERTV(uint64_t cache_phase = P2PHASE(zio->io_offset, VCBS);)
 	zio_t *fio;
@@ -267,8 +267,10 @@ vdev_cache_read(zio_t *zio)
 
 	mutex_enter(&vc->vc_lock);
 
-	ve_search.ve_offset = cache_offset;
-	ve = avl_find(&vc->vc_offset_tree, &ve_search, NULL);
+	ve_search = kmem_alloc(sizeof(vdev_cache_entry_t), KM_SLEEP);
+	ve_search->ve_offset = cache_offset;
+	ve = avl_find(&vc->vc_offset_tree, ve_search, NULL);
+	kmem_free(ve_search, sizeof(vdev_cache_entry_t));
 
 	if (ve != NULL) {
 		if (ve->ve_missed_update) {