From: Chuck Lever <chuck.lever@oracle.com>
Date: Fri, 28 Jan 2011 17:40:55 +0000 (-0500)
Subject: NFS: Micro-optimize nfs4_decode_dirent()
X-Git-Tag: upstream/snapshot3+hdmi~11554^2~1
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c08e76d0cd4beb759a73c1835d98f5fccc126ed1;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

NFS: Micro-optimize nfs4_decode_dirent()

Make the decoding of NFSv4 directory entries slightly more efficient
by:

  1.  Avoiding unnecessary byte swapping when checking XDR booleans,
      and

  2.  Not bumping "p" when its value will be immediately replaced by
      xdr_inline_decode()

This commit makes nfs4_decode_dirent() consistent with similar logic
in the other two decode_dirent() functions.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 2ab8e5c..009aef9 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -6086,11 +6086,11 @@ int nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
 	__be32 *p = xdr_inline_decode(xdr, 4);
 	if (unlikely(!p))
 		goto out_overflow;
-	if (!ntohl(*p++)) {
+	if (*p == xdr_zero) {
 		p = xdr_inline_decode(xdr, 4);
 		if (unlikely(!p))
 			goto out_overflow;
-		if (!ntohl(*p++))
+		if (*p == xdr_zero)
 			return -EAGAIN;
 		entry->eof = 1;
 		return -EBADCOOKIE;
@@ -6101,7 +6101,7 @@ int nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
 		goto out_overflow;
 	entry->prev_cookie = entry->cookie;
 	p = xdr_decode_hyper(p, &entry->cookie);
-	entry->len = ntohl(*p++);
+	entry->len = be32_to_cpup(p);
 
 	p = xdr_inline_decode(xdr, entry->len);
 	if (unlikely(!p))