[PATCH v2] x86: remove unused atomic_inc_short()

From: Dmitry Vyukov
Date: Wed Mar 22 2017 - 13:46:16 EST


It is completely unused and implemented only on x86.
Remove it.

Signed-off-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Suggested-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx

---

Andrew, I think it needs to go into mm as
the atomic-instrumented.h patch is in mm.

Changes since v1:
- change Suggested-by to Mark

---
arch/tile/lib/atomic_asm_32.S | 3 +--
arch/x86/include/asm/atomic.h | 13 -------------
include/asm-generic/atomic-instrumented.h | 6 ------
3 files changed, 1 insertion(+), 21 deletions(-)

diff --git a/arch/tile/lib/atomic_asm_32.S b/arch/tile/lib/atomic_asm_32.S
index 1a70e6c0f259..94709ab41ed8 100644
--- a/arch/tile/lib/atomic_asm_32.S
+++ b/arch/tile/lib/atomic_asm_32.S
@@ -24,8 +24,7 @@
* has an opportunity to return -EFAULT to the user if needed.
* The 64-bit routines just return a "long long" with the value,
* since they are only used from kernel space and don't expect to fault.
- * Support for 16-bit ops is included in the framework but we don't provide
- * any (x86_64 has an atomic_inc_short(), so we might want to some day).
+ * Support for 16-bit ops is included in the framework but we don't provide any.
*
* Note that the caller is advised to issue a suitable L1 or L2
* prefetch on the address being manipulated to avoid extra stalls.
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
index 0cde164f058a..9ff8738103eb 100644
--- a/arch/x86/include/asm/atomic.h
+++ b/arch/x86/include/asm/atomic.h
@@ -237,19 +237,6 @@ ATOMIC_OPS(xor, ^)

int __arch_atomic_add_unless(atomic_t *v, int a, int u);

-/**
- * arch_atomic_inc_short - increment of a short integer
- * @v: pointer to type int
- *
- * Atomically adds 1 to @v
- * Returns the new value of @u
- */
-static __always_inline short int arch_atomic_inc_short(short int *v)
-{
- asm(LOCK_PREFIX "addw $1, %0" : "+m" (*v));
- return *v;
-}
-
#ifdef CONFIG_X86_32
# include <asm/atomic64_32.h>
#else
diff --git a/include/asm-generic/atomic-instrumented.h b/include/asm-generic/atomic-instrumented.h
index 951bcd083925..70742da13087 100644
--- a/include/asm-generic/atomic-instrumented.h
+++ b/include/asm-generic/atomic-instrumented.h
@@ -78,12 +78,6 @@ static __always_inline bool atomic64_add_unless(atomic64_t *v, long long a,
return arch_atomic64_add_unless(v, a, u);
}

-static __always_inline short int atomic_inc_short(short int *v)
-{
- kasan_check_write(v, sizeof(*v));
- return arch_atomic_inc_short(v);
-}
-
#define __INSTR_VOID1(op, sz) \
static __always_inline void atomic##sz##_##op(atomic##sz##_t *v) \
{ \
--
2.12.1.500.gab5fba24ee-goog