From 8a18cc0c2c36ee49d70a620ac0190d30897c15fb Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Sun, 25 Sep 2016 22:35:40 +1000 Subject: [PATCH] powerpc: Only disable HAVE_EFFICIENT_UNALIGNED_ACCESS on POWER7 little endian POWER8 handles unaligned accesses in little endian mode, but commit 0b5e6661ac69 ("powerpc: Don't set HAVE_EFFICIENT_UNALIGNED_ACCESS on little endian builds") disabled it for all. The issue with unaligned little endian accesses is specific to POWER7, so update the Kconfig check to match. Using the stat() testcase from commit a75c380c7129 ("powerpc: Enable DCACHE_WORD_ACCESS on ppc64le"), performance improves 15% on POWER8. Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman --- arch/powerpc/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 243252a8ae04..569b4f9271a4 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -96,7 +96,7 @@ config PPC select VIRT_TO_BUS if !PPC64 select HAVE_IDE select HAVE_IOREMAP_PROT - select HAVE_EFFICIENT_UNALIGNED_ACCESS if !CPU_LITTLE_ENDIAN + select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU) select HAVE_KPROBES select HAVE_ARCH_KGDB select HAVE_KRETPROBES -- 2.20.1