[PATCH] Use unsigned int types for a faster bsearch
authorEric Dumazet <dada1@cosmosbay.com>
Sat, 25 Mar 2006 11:08:19 +0000 (03:08 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Sat, 25 Mar 2006 16:23:01 +0000 (08:23 -0800)
commitd74beb9f33a5f16d2965f11b275e401f225c949d
tree48f851753ebe9c9c8dd701dcdd0c5e1d7c629579
parent34f361ade2fb4a869f6a7714d01c04ce4cfa75d9
[PATCH] Use unsigned int types for a faster bsearch

This patch avoids arithmetic on 'signed' types that are slower than
'unsigned'.  This saves space and cpu cycles.

size of kernel/sys.o before the patch (gcc-3.4.5)

    text    data     bss     dec     hex filename
   10924     252       4   11180    2bac kernel/sys.o

size of kernel/sys.o after the patch
    text    data     bss     dec     hex filename
   10903     252       4   11159    2b97 kernel/sys.o

I noticed that gcc-4.1.0 (from Fedora Core 5) even uses idiv instruction for
(a+b)/2 if a and b are signed.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
kernel/sys.c