Subject: [PATCH 02/10] locking/atomic: Add generic try_cmpxchg{,64}_local support

From: Uros Bizjak <[email-masked]>
Date: Sun, 5 Mar 2023 21:56:20 +0100

Add generic support for try_cmpxchg{,64}_local and their falbacks.

Cc: Will Deacon <[email-masked]>
Cc: Peter Zijlstra <[email-masked]>
Cc: Boqun Feng <[email-masked]>
Cc: Mark Rutland <[email-masked]>
Signed-off-by: Uros Bizjak <[email-masked]>
---
 include/linux/atomic/atomic-arch-fallback.h | 24 ++++++++++++++++++++-
 include/linux/atomic/atomic-instrumented.h  | 20 ++++++++++++++++-
 scripts/atomic/gen-atomic-fallback.sh       |  4 ++++
 scripts/atomic/gen-atomic-instrumented.sh   |  2 +-
 4 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
index 19debd501ee7..a7d2e5f4e548 100644
--- a/include/linux/atomic/atomic-arch-fallback.h
+++ b/include/linux/atomic/atomic-arch-fallback.h
@@ -217,6 +217,28 @@
 
 #endif /* arch_try_cmpxchg64_relaxed */
 
+#ifndef arch_try_cmpxchg_local
+#define arch_try_cmpxchg_local(_ptr, _oldp, _new) \
+({ \
+	typeof(*(_ptr)) *___op = (typeof(_ptr))(_oldp), ___o = *___op, ___r; \
+	___r = arch_cmpxchg_local((_ptr), ___o, (_new)); \
+	if (unlikely(___r != ___o)) \
+		*___op = ___r; \
+	likely(___r == ___o); \
+})
+#endif /* arch_try_cmpxchg_local */
+
+#ifndef arch_try_cmpxchg64_local
+#define arch_try_cmpxchg64_local(_ptr, _oldp, _new) \
+({ \
+	typeof(*(_ptr)) *___op = (typeof(_ptr))(_oldp), ___o = *___op, ___r; \
+	___r = arch_cmpxchg64_local((_ptr), ___o, (_new)); \
+	if (unlikely(___r != ___o)) \
+		*___op = ___r; \
+	likely(___r == ___o); \
+})
+#endif /* arch_try_cmpxchg64_local */
+
 #ifndef arch_atomic_read_acquire
 static __always_inline int
 arch_atomic_read_acquire(const atomic_t *v)
@@ -2456,4 +2478,4 @@ arch_atomic64_dec_if_positive(atomic64_t *v)
 #endif
 
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
-// 1b4d4c82ae653389cd1538d5b07170267d9b3837
+// 9bb8cca3d4cbc000e7068eb7cb4481cb3e48c45a
diff --git a/include/linux/atomic/atomic-instrumented.h b/include/linux/atomic/atomic-instrumented.h
index 7a139ec030b0..14a9212cc987 100644
--- a/include/linux/atomic/atomic-instrumented.h
+++ b/include/linux/atomic/atomic-instrumented.h
@@ -2066,6 +2066,24 @@ atomic_long_dec_if_positive(atomic_long_t *v)
 	arch_sync_cmpxchg(__ai_ptr, __VA_ARGS__); \
 })
 
+#define try_cmpxchg_local(ptr, oldp, ...) \
+({ \
+	typeof(ptr) __ai_ptr = (ptr); \
+	typeof(oldp) __ai_oldp = (oldp); \
+	instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+	instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+	arch_try_cmpxchg_local(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+
+#define try_cmpxchg64_local(ptr, oldp, ...) \
+({ \
+	typeof(ptr) __ai_ptr = (ptr); \
+	typeof(oldp) __ai_oldp = (oldp); \
+	instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+	instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+	arch_try_cmpxchg64_local(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+
 #define cmpxchg_double(ptr, ...) \
 ({ \
 	typeof(ptr) __ai_ptr = (ptr); \
@@ -2083,4 +2101,4 @@ atomic_long_dec_if_positive(atomic_long_t *v)
 })
 
 #endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
-// 764f741eb77a7ad565dc8d99ce2837d5542e8aee
+// 456e206c7e4e681126c482e4edcc6f46921ac731
diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
index 39f447161108..26829a75b644 100755
--- a/scripts/atomic/gen-atomic-fallback.sh
+++ b/scripts/atomic/gen-atomic-fallback.sh
@@ -225,6 +225,10 @@ for cmpxchg in "cmpxchg" "cmpxchg64"; do
 	gen_try_cmpxchg_fallbacks "${cmpxchg}"
 done
 
+for cmpxchg in "cmpxchg_local" "cmpxchg64_local"; do
+	gen_try_cmpxchg_fallback "${cmpxchg}" ""
+done
+
 grep '^[a-z]' "$1" | while read name meta args; do
 	gen_proto "${meta}" "${name}" "atomic" "int" ${args}
 done
diff --git a/scripts/atomic/gen-atomic-instrumented.sh b/scripts/atomic/gen-atomic-instrumented.sh
index 77c06526a574..c8165e9431bf 100755
--- a/scripts/atomic/gen-atomic-instrumented.sh
+++ b/scripts/atomic/gen-atomic-instrumented.sh
@@ -173,7 +173,7 @@ for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg" "try_cmpxchg64"; do
 	done
 done
 
-for xchg in "cmpxchg_local" "cmpxchg64_local" "sync_cmpxchg"; do
+for xchg in "cmpxchg_local" "cmpxchg64_local" "sync_cmpxchg" "try_cmpxchg_local" "try_cmpxchg64_local" ; do
 	gen_xchg "${xchg}" "" ""
 	printf "\n"
 done
-- 
2.39.2