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[PATCH 24/34] sh: define __smp_xxx, fix smp_store_mb for !SMP

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sh variant of smp_store_mb() calls xchg() on !SMP which is stronger than
implied by both the name and the documentation.

define __smp_store_mb instead: code in asm-generic/barrier.h
will then define smp_store_mb correctly depending on
CONFIG_SMP.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 arch/sh/include/asm/barrier.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/sh/include/asm/barrier.h b/arch/sh/include/asm/barrier.h
index bf91037..f887c64 100644
--- a/arch/sh/include/asm/barrier.h
+++ b/arch/sh/include/asm/barrier.h
@@ -32,7 +32,8 @@
 #define ctrl_barrier()	__asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
 #endif
 
-#define smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
+#define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
+#define smp_store_mb(var, value) __smp_store_mb(var, value)
 
 #include <asm-generic/barrier.h>
 
-- 
MST

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Thread

[PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for virt "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 20:40 +0100
  Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for  virt David Miller <davem@davemloft.net> - 2015-12-30 21:50 +0100
    Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for virt "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 22:40 +0100
      Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for  virt David Miller <davem@davemloft.net> - 2015-12-30 23:00 +0100
  [PATCH 17/34] arm64: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 22:50 +0100
  [PATCH 18/34] arm: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 22:50 +0100
  Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for virt "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 22:50 +0100
    Re: [PATCH 00/34] arch: barrier cleanup + __smp_xxx barriers for virt Arnd Bergmann <arnd@arndb.de> - 2015-12-30 23:50 +0100
  [PATCH 20/34] ia64: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 28/34] x86: define __smp_xxX "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 26/34] tile: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 31/34] xenbus: use __smp_xxx barriers "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 23/34] s390: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 21/34] metag: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 22/34] mips: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 24/34] sh: define __smp_xxx, fix smp_store_mb for !SMP "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 27/34] xtensa: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 25/34] sparc: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 19/34] blackfin: define __smp_xxx "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100
  [PATCH 32/34] xen/io: use __smp_xxx barriers "Michael S. Tsirkin" <mst@redhat.com> - 2015-12-30 23:00 +0100

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