From: David Daney Date: Fri, 14 May 2010 19:44:18 +0000 (-0700) Subject: MIPS: Use GCC __builtin_prefetch() to implement prefetch(). X-Git-Tag: v2.6.35-rc1~443^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0453fb3c528c5eb3483441a466b24a4cb409eec5;p=platform%2Fkernel%2Flinux-exynos.git MIPS: Use GCC __builtin_prefetch() to implement prefetch(). GCC's __builtin_prefetch() was introduced a long time ago, all supported GCC versions have it. Lets do what the big boys up in linux/prefetch.h do, except we use '1' as the third parameter to provoke 'PREF 0,...' and 'PREF 1,...' instead of other prefetch hints. This allows for better code generation. In theory the existing embedded asm could be optimized, but the compiler has these builtins, so there is really no point. Signed-off-by: David Daney To: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/1235/ Signed-off-by: Ralf Baechle --- diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index ab38791..5d33b72 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -344,16 +344,10 @@ unsigned long get_wchan(struct task_struct *p); #ifdef CONFIG_CPU_HAS_PREFETCH #define ARCH_HAS_PREFETCH +#define prefetch(x) __builtin_prefetch((x), 0, 1) -static inline void prefetch(const void *addr) -{ - __asm__ __volatile__( - " .set mips4 \n" - " pref %0, (%1) \n" - " .set mips0 \n" - : - : "i" (Pref_Load), "r" (addr)); -} +#define ARCH_HAS_PREFETCHW +#define prefetchw(x) __builtin_prefetch((x), 1, 1) #endif