atomics/treewide: Make atomic64_inc_not_zero() optional

We define a trivial fallback for atomic_inc_not_zero(), but don't do
the same for atomic64_inc_not_zero(), leading most architectures to
define the same boilerplate.

Let's add a fallback in <linux/atomic.h>, and remove the redundant
implementations. Note that atomic64_add_unless() is always defined in
<linux/atomic.h>, and promotes its arguments to the requisite types, so
we need not do this explicitly.

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>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
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/20180621121321.4761-6-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 0 insertions, 2 deletions

diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 6106b59d3260..6f95023894b7 100644
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -207,8 +207,6 @@ static inline bool arch_atomic64_add_unless(atomic64_t *v, long a, long u)
 	return true;
 }
 
-#define arch_atomic64_inc_not_zero(v) arch_atomic64_add_unless((v), 1, 0)
-
 /*
  * arch_atomic64_dec_if_positive - decrement by 1 if old value positive
  * @v: pointer of type atomic_t