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authorPeter Zijlstra <peterz@infradead.org>2016-04-18 01:16:04 +0200
committerIngo Molnar <mingo@kernel.org>2016-06-16 10:48:29 +0200
commit7d9794e7523798e1b9422ad9f4e4d808ae5d5932 (patch)
tree3a1a550803485049b8e8c2a434c0c9107831f3a6 /arch/sh/include/asm/atomic.h
parentlocking/atomic, arch/s390: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() (diff)
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locking/atomic, arch/sh: Implement atomic_fetch_{add,sub,and,or,xor}()
Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-sh@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to '')
-rw-r--r--arch/sh/include/asm/atomic.h2
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h
index c399e1c55685..d93ed7ce1b2f 100644
--- a/arch/sh/include/asm/atomic.h
+++ b/arch/sh/include/asm/atomic.h
@@ -25,6 +25,8 @@
#include <asm/atomic-irq.h>
#endif
+#define atomic_fetch_or atomic_fetch_or
+
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic_dec_return(v) atomic_sub_return(1, (v))
#define atomic_inc_return(v) atomic_add_return(1, (v))