summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJason Gunthorpe <jgg@nvidia.com>2025-04-08 14:22:56 -0300
committerVineet Gupta <vgupta@kernel.org>2025-06-09 09:18:12 -0700
commitea7caffedd011f7d40abe93a884ffbe46f122535 (patch)
tree5150133adef8320934dd7a3f0a6405cd19138882
parent19272b37aa4f83ca52bdf9c16d5d81bdd1354494 (diff)
ARC: atomics: Implement arch_atomic64_cmpxchg using _relaxed
The core atomic code has a number of macros where it elaborates architecture primitives into more functions. ARC uses arch_atomic64_cmpxchg() as it's architecture primitive which disable alot of the additional functions. Instead provide arch_cmpxchg64_relaxed() as the primitive and rely on the core macros to create arch_cmpxchg64(). The macros will also provide other functions, for instance, try_cmpxchg64_release(), giving a more complete implementation. Suggested-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/Z0747n5bSep4_1VX@J2N7QTR9R3 Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Vineet Gupta <vgupta@kernel.org>
-rw-r--r--arch/arc/include/asm/atomic64-arcv2.h15
1 files changed, 5 insertions, 10 deletions
diff --git a/arch/arc/include/asm/atomic64-arcv2.h b/arch/arc/include/asm/atomic64-arcv2.h
index 9b5791b85471..73080a664369 100644
--- a/arch/arc/include/asm/atomic64-arcv2.h
+++ b/arch/arc/include/asm/atomic64-arcv2.h
@@ -137,12 +137,9 @@ ATOMIC64_OPS(xor, xor, xor)
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP
-static inline s64
-arch_atomic64_cmpxchg(atomic64_t *ptr, s64 expected, s64 new)
+static inline u64 __arch_cmpxchg64_relaxed(volatile void *ptr, u64 old, u64 new)
{
- s64 prev;
-
- smp_mb();
+ u64 prev;
__asm__ __volatile__(
"1: llockd %0, [%1] \n"
@@ -152,14 +149,12 @@ arch_atomic64_cmpxchg(atomic64_t *ptr, s64 expected, s64 new)
" bnz 1b \n"
"2: \n"
: "=&r"(prev)
- : "r"(ptr), "ir"(expected), "r"(new)
- : "cc"); /* memory clobber comes from smp_mb() */
-
- smp_mb();
+ : "r"(ptr), "ir"(old), "r"(new)
+ : "memory", "cc");
return prev;
}
-#define arch_atomic64_cmpxchg arch_atomic64_cmpxchg
+#define arch_cmpxchg64_relaxed __arch_cmpxchg64_relaxed
static inline s64 arch_atomic64_xchg(atomic64_t *ptr, s64 new)
{