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, 7 deletions

diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index 0e27e050ba14..18259e90f57e 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -375,13 +375,6 @@ static __always_inline int atomic64_add_unless(atomic64_t *v, long a, long u)
 }
 #endif
 
-#ifndef CONFIG_GENERIC_ATOMIC64
-static __always_inline long atomic64_inc_not_zero(atomic64_t *v)
-{
-        return atomic64_add_unless(v, 1, 0);
-}
-#endif
-
 /*
  * atomic_{cmp,}xchg is required to have exactly the same ordering semantics as
  * {cmp,}xchg and the operations that return, so they need a full barrier.