Commit 8a18cc0c authored by Anton Blanchard's avatar Anton Blanchard Committed by Michael Ellerman
Browse files

powerpc: Only disable HAVE_EFFICIENT_UNALIGNED_ACCESS on POWER7 little endian 



POWER8 handles unaligned accesses in little endian mode, but commit
0b5e6661 ("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 a75c380c ("powerpc: Enable DCACHE_WORD_ACCESS on ppc64le"),
performance improves 15% on POWER8.

Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 61e98ebf

arch/powerpc/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -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

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