[PATCH 1/1] JFS: performance patch

JFS: performance patch

Basically, we saw a large amount of time spent in the
jfs_strfromUCS_le() function, mispredicting the branch inside the
loop, so I just added some unlikely modifiers to the if statements to
re-ordered the code.  Again, these simple changes provided > 2 % on
spec-sfs, so please consider it for inclusion.

Signed-off-by: Dave Kleikamp <[email protected]>

---
commit f5f287738bddf38ec9ca79344f00dab675e1bbf5
tree c8144a3906f6904f7cf18c4520976c79a1e15b0a
parent a8ad86f2dc46356f87be1327dabc18bdbda32f50
author Sonny Rao <[email protected]> Thu, 23 Jun 2005 16:57:56 -0500
committer Dave Kleikamp <[email protected]> Thu, 23 Jun 2005 16:57:56 -0500

 fs/jfs/jfs_unicode.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/jfs/jfs_unicode.c b/fs/jfs/jfs_unicode.c
--- a/fs/jfs/jfs_unicode.c
+++ b/fs/jfs/jfs_unicode.c
@@ -51,8 +51,9 @@ int jfs_strfromUCS_le(char *to, const __
 		}
 	} else {
 		for (i = 0; (i < len) && from[i]; i++) {
-			if (le16_to_cpu(from[i]) & 0xff00) {
-				if (warn) {
+			if (unlikely(le16_to_cpu(from[i]) & 0xff00)) {
+				to[i] = '?';
+				if (unlikely(warn)) {
 					warn--;
 					warn_again--;
 					printk(KERN_ERR
@@ -61,7 +62,7 @@ int jfs_strfromUCS_le(char *to, const __
 					printk(KERN_ERR
 				"mount with iocharset=utf8 to access\n");
 				}
-				to[i] = '?';
+
 			}
 			else
 				to[i] = (char) (le16_to_cpu(from[i]));


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