[PATCH v2 13/27] locking/atomic: xtensa: add preprocessor symbols

From: Mark Rutland
Date: Mon Jun 05 2023 - 03:03:07 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/xtensa.

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/xtensa/include/asm/atomic.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h
index 1d323a864002c..7308b7f777d79 100644
--- a/arch/xtensa/include/asm/atomic.h
+++ b/arch/xtensa/include/asm/atomic.h
@@ -245,6 +245,11 @@ static inline int arch_atomic_fetch_##op(int i, atomic_t * v) \
ATOMIC_OPS(add)
ATOMIC_OPS(sub)

+#define arch_atomic_add_return arch_atomic_add_return
+#define arch_atomic_sub_return arch_atomic_sub_return
+#define arch_atomic_fetch_add arch_atomic_fetch_add
+#define arch_atomic_fetch_sub arch_atomic_fetch_sub
+
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)

@@ -252,6 +257,10 @@ ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)

+#define arch_atomic_fetch_and arch_atomic_fetch_and
+#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
#undef ATOMIC_OP_RETURN
--
2.30.2