[PATCH 11/11] ARC: atomic_cmpxchg/atomic_xchg: implement relaxed variants
Vineet Gupta
Vineet.Gupta1 at synopsys.com
Wed Aug 4 12:15:54 PDT 2021
And move them out of cmpxchg.h to canonical atomic.h
Signed-off-by: Vineet Gupta <vgupta at synopsys.com>
---
arch/arc/include/asm/atomic.h | 27 +++++++++++++++++++++++++++
arch/arc/include/asm/cmpxchg.h | 23 -----------------------
2 files changed, 27 insertions(+), 23 deletions(-)
diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h
index ee88e1dbaab5..52ee51e1ff7c 100644
--- a/arch/arc/include/asm/atomic.h
+++ b/arch/arc/include/asm/atomic.h
@@ -22,6 +22,33 @@
#include <asm/atomic-spinlock.h>
#endif
+#define arch_atomic_cmpxchg(v, o, n) \
+({ \
+ arch_cmpxchg(&((v)->counter), (o), (n)); \
+})
+
+#ifdef arch_cmpxchg_relaxed
+#define arch_atomic_cmpxchg_relaxed(v, o, n) \
+({ \
+ arch_cmpxchg_relaxed(&((v)->counter), (o), (n)); \
+})
+#endif
+
+#define arch_atomic_xchg(v, n) \
+({ \
+ arch_xchg(&((v)->counter), (n)); \
+})
+
+#ifdef arch_xchg_relaxed
+#define arch_atomic_xchg_relaxed(v, n) \
+({ \
+ arch_xchg_relaxed(&((v)->counter), (n)); \
+})
+#endif
+
+/*
+ * 64-bit atomics
+ */
#ifdef CONFIG_GENERIC_ATOMIC64
#include <asm-generic/atomic64.h>
#else
diff --git a/arch/arc/include/asm/cmpxchg.h b/arch/arc/include/asm/cmpxchg.h
index e2ae0eb1ca07..c5b544a5fe81 100644
--- a/arch/arc/include/asm/cmpxchg.h
+++ b/arch/arc/include/asm/cmpxchg.h
@@ -80,14 +80,6 @@
#endif
-/*
- * atomic_cmpxchg is same as cmpxchg
- * LLSC: only different in data-type, semantics are exactly same
- * !LLSC: cmpxchg() has to use an external lock atomic_ops_lock to guarantee
- * semantics, and this lock also happens to be used by atomic_*()
- */
-#define arch_atomic_cmpxchg(v, o, n) ((int)arch_cmpxchg(&((v)->counter), (o), (n)))
-
/*
* xchg
*/
@@ -148,19 +140,4 @@
#endif
-/*
- * "atomic" variant of xchg()
- * REQ: It needs to follow the same serialization rules as other atomic_xxx()
- * Since xchg() doesn't always do that, it would seem that following definition
- * is incorrect. But here's the rationale:
- * SMP : Even xchg() takes the atomic_ops_lock, so OK.
- * LLSC: atomic_ops_lock are not relevant at all (even if SMP, since LLSC
- * is natively "SMP safe", no serialization required).
- * UP : other atomics disable IRQ, so no way a difft ctxt atomic_xchg()
- * could clobber them. atomic_xchg() itself would be 1 insn, so it
- * can't be clobbered by others. Thus no serialization required when
- * atomic_xchg is involved.
- */
-#define arch_atomic_xchg(v, new) (arch_xchg(&((v)->counter), new))
-
#endif
--
2.25.1
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