[ar71xx] remove duplicated includes
[openwrt.git] / target / linux / s3c24xx / patches-2.6.24 / 1300-fix-gcc-4.3-false-modulo-optimization.patch.patch
1 From f5b973489beb1a1239dfad53e3ad6e36ff7ee958 Mon Sep 17 00:00:00 2001
2 From: Segher Boessenkool <segher@kernel.crashing.org>
3 Date: Thu, 9 Oct 2008 21:18:27 +0100
4 Subject: [PATCH] fix-gcc-4.3-false-modulo-optimization.patch
5
6 I tried to compile the current stable kernel
7 (a2ef813d2f439a3e9f377d33a2e5baad098afb7e)
8 and get the following errors:
9
10 kernel/built-in.o: In function `timespec_add_ns':
11 /mnt/data/Freerunner/Gentoo/rootinstall/usr/src/linux/include/linux/time.h:174:
12 undefined reference to `__aeabi_uldivmod'
13 /mnt/data/Freerunner/Gentoo/rootinstall/usr/src/linux/include/linux/time.h:179:
14 undefined reference to `__aeabi_uldivmod'
15 /mnt/data/Freerunner/Gentoo/rootinstall/usr/src/linux/include/linux/time.h:174:
16 undefined reference to `__aeabi_uldivmod'
17 /mnt/data/Freerunner/Gentoo/rootinstall/usr/src/linux/include/linux/time.h:179:
18 undefined reference to `__aeabi_uldivmod'
19
20 applying the following patch solved the problem:
21 --------
22 Prevent gcc-4.3 form "optimizing" the while loop into a costly modulo operation.
23 Patch found at http://lkml.org/lkml/2008/2/22/464.
24
25 Reported-by: Sven Rebhan <odinshorse@googlemail.com>
26 Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
27 ---
28 include/linux/time.h | 4 ++++
29 1 files changed, 4 insertions(+), 0 deletions(-)
30
31 diff --git a/include/linux/time.h b/include/linux/time.h
32 index b04136d..3e8fd9e 100644
33 --- a/include/linux/time.h
34 +++ b/include/linux/time.h
35 @@ -173,6 +173,10 @@ static inline void timespec_add_ns(struct timespec *a, u64 ns)
36 {
37 ns += a->tv_nsec;
38 while(unlikely(ns >= NSEC_PER_SEC)) {
39 + /* The following asm() prevents the compiler from
40 + * optimising this loop into a modulo operation. */
41 + asm("" : "+r"(ns));
42 +
43 ns -= NSEC_PER_SEC;
44 a->tv_sec++;
45 }
46 --
47 1.5.6.5
48
This page took 0.057187 seconds and 5 git commands to generate.