From: Jeff Layton <jlayton@redhat.com>
Date: Mon, 28 Jan 2013 19:41:08 +0000 (-0500)
Subject: nfsd: remove unneeded spinlock in nfsd_cache_update
X-Git-Tag: accepted/tizen/common/20141203.182822~2756^2~38
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6dc8889589678c228a675b9f01721318a31a8f5b;p=platform%2Fkernel%2Flinux-arm64.git

nfsd: remove unneeded spinlock in nfsd_cache_update

The locking rules for cache entries say that locking the cache_lock
isn't needed if you're just touching the current entry. Earlier
in this function we set rp->c_state to RC_UNUSED without any locking,
so I believe it's ok to do the same here.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 5dd9ec2..972c14a 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -286,9 +286,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
 		cachv = &rp->c_replvec;
 		cachv->iov_base = kmalloc(len << 2, GFP_KERNEL);
 		if (!cachv->iov_base) {
-			spin_lock(&cache_lock);
 			rp->c_state = RC_UNUSED;
-			spin_unlock(&cache_lock);
 			return;
 		}
 		cachv->iov_len = len << 2;