diff options
author | Denys Vlasenko <vda.linux@googlemail.com> | 2008-02-09 23:24:09 +0100 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2008-02-09 23:24:09 +0100 |
commit | 9b706aee7d92d6ac3002547aea12e3eaa0a750ae (patch) | |
tree | b1e945b7d6eccd4ef44d80e1f3a4596a4a629c78 /arch/x86/kernel/cpu | |
parent | b6fbb669c8ef3a112121697ca901c290ccd35eb2 (diff) |
x86: trivial printk optimizations
In arch/x86/boot/printf.c gets rid of unused tail of digits: const char
*digits = "0123456789abcdefghijklmnopqrstuvwxyz"; (we are using 0-9a-f
only)
Uses smaller/faster lowercasing (by ORing with 0x20)
if we know that we work on numbers/digits. Makes
strtoul smaller, and also we are getting rid of
static const char small_digits[] = "0123456789abcdefx";
static const char large_digits[] = "0123456789ABCDEFX";
since this works equally well:
static const char digits[16] = "0123456789ABCDEF";
Size savings:
$ size vmlinux.org vmlinux
text data bss dec hex filename
877320 112252 90112 1079684 107984 vmlinux.org
877048 112252 90112 1079412 107874 vmlinux
It may be also a tiny bit faster because code has less
branches now, but I doubt it is measurable.
[ hugh@veritas.com: uppercase pointers fix ]
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/cpu')
0 files changed, 0 insertions, 0 deletions