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author | Mark Rutland <mark.rutland@arm.com> | 2018-06-21 14:13:17 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2018-06-21 14:25:24 +0200 |
commit | 356701329fb391184618eda7b7fb68cb35271506 (patch) | |
tree | 4d9dc75f1a20215b12ec4f5c40870de290264484 /arch/x86/include | |
parent | atomics/riscv: Define atomic64_fetch_add_unless() (diff) | |
download | linux-356701329fb391184618eda7b7fb68cb35271506.tar.xz linux-356701329fb391184618eda7b7fb68cb35271506.zip |
atomics/treewide: Make atomic64_fetch_add_unless() optional
Architectures with atomic64_fetch_add_unless() provide a preprocessor
symbol if they do so, and all other architectures have trivial C
implementations of atomic64_add_unless() which are near-identical.
Let's unify the trivial definitions of atomic64_fetch_add_unless() in
<linux/atomic.h>, so that we always have both
atomic64_fetch_add_unless() and atomic64_add_unless() with less
boilerplate code.
This means that atomic64_add_unless() is always implemented in core
code, and the instrumented atomics are updated accordingly.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-15-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include')
-rw-r--r-- | arch/x86/include/asm/atomic64_64.h | 19 |
1 files changed, 0 insertions, 19 deletions
diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h index 6f95023894b7..7e04b294e6eb 100644 --- a/arch/x86/include/asm/atomic64_64.h +++ b/arch/x86/include/asm/atomic64_64.h @@ -188,25 +188,6 @@ static inline long arch_atomic64_xchg(atomic64_t *v, long new) return xchg(&v->counter, new); } -/** - * arch_atomic64_add_unless - add unless the number is a given value - * @v: pointer of type atomic64_t - * @a: the amount to add to v... - * @u: ...unless v is equal to u. - * - * Atomically adds @a to @v, so long as it was not @u. - * Returns the old value of @v. - */ -static inline bool arch_atomic64_add_unless(atomic64_t *v, long a, long u) -{ - s64 c = arch_atomic64_read(v); - do { - if (unlikely(c == u)) - return false; - } while (!arch_atomic64_try_cmpxchg(v, &c, c + a)); - return true; -} - /* * arch_atomic64_dec_if_positive - decrement by 1 if old value positive * @v: pointer of type atomic_t |