From d9ada91ae2969ae6b6dc3574fd08a6ebda5df766 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 2 Mar 2012 11:33:52 +1100 Subject: powerpc: Replace mfmsr instructions with load from PACA kernel_msr field On 64-bit, the mfmsr instruction can be quite slow, slower than loading a field from the cache-hot PACA, which happens to already contain the value we want in most cases. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/include/asm/exception-64s.h') diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 7f4718c4f04a..70354af0740e 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -298,7 +298,7 @@ label##_hv: \ /* Exception addition: Keep interrupt state */ #define ENABLE_INTS \ - mfmsr r11; \ + ld r11,PACAKMSR(r13); \ ld r12,_MSR(r1); \ rlwimi r11,r12,0,MSR_EE; \ mtmsrd r11,1 -- cgit