[PATCH v2 05/27] locking/atomic: arc: add preprocessor symbols

From: Mark Rutland
Date: Mon Jun 05 2023 - 03:02:19 EST


Some atomics can be implemented in several different ways, e.g.
FULL/ACQUIRE/RELEASE ordered atomics can be implemented in terms of
RELAXED atomics, and ACQUIRE/RELEASE/RELAXED can be implemented in terms
of FULL ordered atomics. Other atomics are optional, and don't exist in
some configurations (e.g. not all architectures implement the 128-bit
cmpxchg ops).

Subsequent patches will require that architectures define a preprocessor
symbol for any atomic (or ordering variant) which is optional. This will
make the fallback ifdeffery more robust, and simplify future changes.

Add the required definitions to arch/arc.

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
arch/arc/include/asm/atomic-spinlock.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/arc/include/asm/atomic-spinlock.h b/arch/arc/include/asm/atomic-spinlock.h
index 2c830347bfb4e..89d12a60f84c0 100644
--- a/arch/arc/include/asm/atomic-spinlock.h
+++ b/arch/arc/include/asm/atomic-spinlock.h
@@ -81,6 +81,11 @@ static inline int arch_atomic_fetch_##op(int i, atomic_t *v) \
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)

+#define arch_atomic_fetch_add arch_atomic_fetch_add
+#define arch_atomic_fetch_sub arch_atomic_fetch_sub
+#define arch_atomic_add_return arch_atomic_add_return
+#define arch_atomic_sub_return arch_atomic_sub_return
+
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
@@ -92,7 +97,11 @@ ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, xor)

#define arch_atomic_andnot arch_atomic_andnot
+
+#define arch_atomic_fetch_and arch_atomic_fetch_and
#define arch_atomic_fetch_andnot arch_atomic_fetch_andnot
+#define arch_atomic_fetch_or arch_atomic_fetch_or
+#define arch_atomic_fetch_xor arch_atomic_fetch_xor

#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
--
2.30.2