From e87fc0ec070554e34812be68267a9450271868d6 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 18 Apr 2016 01:16:08 +0200 Subject: locking/atomic, arch/blackfin: 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) Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Steven Miao Cc: Thomas Gleixner Cc: adi-buildroot-devel@lists.sourceforge.net Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- arch/blackfin/include/asm/atomic.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/blackfin/include') diff --git a/arch/blackfin/include/asm/atomic.h b/arch/blackfin/include/asm/atomic.h index 1c1c423..63c7dec 100644 --- a/arch/blackfin/include/asm/atomic.h +++ b/arch/blackfin/include/asm/atomic.h @@ -17,6 +17,7 @@ asmlinkage int __raw_uncached_fetch_asm(const volatile int *ptr); asmlinkage int __raw_atomic_add_asm(volatile int *ptr, int value); +asmlinkage int __raw_atomic_xadd_asm(volatile int *ptr, int value); asmlinkage int __raw_atomic_and_asm(volatile int *ptr, int value); asmlinkage int __raw_atomic_or_asm(volatile int *ptr, int value); @@ -28,10 +29,17 @@ asmlinkage int __raw_atomic_test_asm(const volatile int *ptr, int value); #define atomic_add_return(i, v) __raw_atomic_add_asm(&(v)->counter, i) #define atomic_sub_return(i, v) __raw_atomic_add_asm(&(v)->counter, -(i)) +#define atomic_fetch_add(i, v) __raw_atomic_xadd_asm(&(v)->counter, i) +#define atomic_fetch_sub(i, v) __raw_atomic_xadd_asm(&(v)->counter, -(i)) + #define atomic_or(i, v) (void)__raw_atomic_or_asm(&(v)->counter, i) #define atomic_and(i, v) (void)__raw_atomic_and_asm(&(v)->counter, i) #define atomic_xor(i, v) (void)__raw_atomic_xor_asm(&(v)->counter, i) +#define atomic_fetch_or(i, v) __raw_atomic_or_asm(&(v)->counter, i) +#define atomic_fetch_and(i, v) __raw_atomic_and_asm(&(v)->counter, i) +#define atomic_fetch_xor(i, v) __raw_atomic_xor_asm(&(v)->counter, i) + #endif #include -- cgit v1.1