From a42548a18866e87092db93b771e6c5b060d78401 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 29 Jul 2009 12:15:29 +0200 Subject: cputime: Optimize jiffies_to_cputime(1) For powerpc with CONFIG_VIRT_CPU_ACCOUNTING jiffies_to_cputime(1) is not compile time constant and run time calculations are quite expensive. To optimize we use precomputed value. For all other architectures is is preprocessor definition. Signed-off-by: Stanislaw Gruszka Acked-by: Peter Zijlstra Acked-by: Thomas Gleixner Cc: Oleg Nesterov Cc: Andrew Morton Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <1248862529-6063-5-git-send-email-sgruszka@redhat.com> Signed-off-by: Ingo Molnar --- arch/s390/include/asm/cputime.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 7a3817a656d..24b1244aadb 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -42,6 +42,7 @@ __div(unsigned long long n, unsigned int base) #endif /* __s390x__ */ #define cputime_zero (0ULL) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~0UL >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) -- cgit v1.2.3