4.9-stable review patch. If anyone has any objections, please let me know.
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From: Nicholas Piggin npiggin@gmail.com
commit 0bfdf598900fd62869659f360d3387ed80eb71cf upstream.
asm/barrier.h is not always included after asm/synch.h, which meant it was missing __SUBARCH_HAS_LWSYNC, so in some files smp_wmb() would be eieio when it should be lwsync. kernel/time/hrtimer.c is one case.
__SUBARCH_HAS_LWSYNC is only used in one place, so just fold it in to where it's used. Previously with my small simulator config, 377 instances of eieio in the tree. After this patch there are 55.
Fixes: 46d075be585e ("powerpc: Optimise smp_wmb") Cc: stable@vger.kernel.org # v2.6.29+ Signed-off-by: Nicholas Piggin npiggin@gmail.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/powerpc/include/asm/barrier.h | 3 ++- arch/powerpc/include/asm/synch.h | 4 ---- 2 files changed, 2 insertions(+), 5 deletions(-)
--- a/arch/powerpc/include/asm/barrier.h +++ b/arch/powerpc/include/asm/barrier.h @@ -34,7 +34,8 @@ #define rmb() __asm__ __volatile__ ("sync" : : : "memory") #define wmb() __asm__ __volatile__ ("sync" : : : "memory")
-#ifdef __SUBARCH_HAS_LWSYNC +/* The sub-arch has lwsync */ +#if defined(__powerpc64__) || defined(CONFIG_PPC_E500MC) # define SMPWMB LWSYNC #else # define SMPWMB eieio --- a/arch/powerpc/include/asm/synch.h +++ b/arch/powerpc/include/asm/synch.h @@ -5,10 +5,6 @@ #include <linux/stringify.h> #include <asm/feature-fixups.h>
-#if defined(__powerpc64__) || defined(CONFIG_PPC_E500MC) -#define __SUBARCH_HAS_LWSYNC -#endif - #ifndef __ASSEMBLY__ extern unsigned int __start___lwsync_fixup, __stop___lwsync_fixup; extern void do_lwsync_fixups(unsigned long value, void *fixup_start,