Commit f5f28773 authored by Sonny Rao's avatar Sonny Rao Committed by Dave Kleikamp

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: default avatarDave Kleikamp <shaggy@austin.ibm.com>
parent a8ad86f2
...@@ -51,8 +51,9 @@ int jfs_strfromUCS_le(char *to, const __le16 * from, ...@@ -51,8 +51,9 @@ int jfs_strfromUCS_le(char *to, const __le16 * from,
} }
} else { } else {
for (i = 0; (i < len) && from[i]; i++) { for (i = 0; (i < len) && from[i]; i++) {
if (le16_to_cpu(from[i]) & 0xff00) { if (unlikely(le16_to_cpu(from[i]) & 0xff00)) {
if (warn) { to[i] = '?';
if (unlikely(warn)) {
warn--; warn--;
warn_again--; warn_again--;
printk(KERN_ERR printk(KERN_ERR
...@@ -61,7 +62,7 @@ int jfs_strfromUCS_le(char *to, const __le16 * from, ...@@ -61,7 +62,7 @@ int jfs_strfromUCS_le(char *to, const __le16 * from,
printk(KERN_ERR printk(KERN_ERR
"mount with iocharset=utf8 to access\n"); "mount with iocharset=utf8 to access\n");
} }
to[i] = '?';
} }
else else
to[i] = (char) (le16_to_cpu(from[i])); to[i] = (char) (le16_to_cpu(from[i]));
......
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