locking/atomics: Flip fallbacks and instrumentation

Currently instrumentation of atomic primitives is done at the architecture
level, while composites or fallbacks are provided at the generic level.

The result is that there are no uninstrumented variants of the
fallbacks. Since there is now need of such variants to isolate text poke
from any form of instrumentation invert this ordering.

Doing this means moving the instrumentation into the generic code as
well as having (for now) two variants of the fallbacks.

Notes:

 - the various *cond_read* primitives are not proper fallbacks
   and got moved into linux/atomic.c. No arch_ variants are
   generated because the base primitives smp_cond_load*()
   are instrumented.

 - once all architectures are moved over to arch_atomic_ one of the
   fallback variants can be removed and some 2300 lines reclaimed.

 - atomic_{read,set}*() are no longer double-instrumented

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20200505134058.769149955@linutronix.de

1 files changed, 12 insertions, 3 deletions

diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 95c6ceac66b9..809bd010a751 100644
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -19,7 +19,7 @@
  */
 static inline s64 arch_atomic64_read(const atomic64_t *v)
 {
-	return READ_ONCE((v)->counter);
+	return __READ_ONCE((v)->counter);
 }
 
 /**
@@ -31,7 +31,7 @@ static inline s64 arch_atomic64_read(const atomic64_t *v)
  */
 static inline void arch_atomic64_set(atomic64_t *v, s64 i)
 {
-	WRITE_ONCE(v->counter, i);
+	__WRITE_ONCE(v->counter, i);
 }
 
 /**
@@ -159,37 +159,43 @@ static __always_inline s64 arch_atomic64_add_return(s64 i, atomic64_t *v)
 {
 	return i + xadd(&v->counter, i);
 }
+#define arch_atomic64_add_return arch_atomic64_add_return
 
 static inline s64 arch_atomic64_sub_return(s64 i, atomic64_t *v)
 {
 	return arch_atomic64_add_return(-i, v);
 }
+#define arch_atomic64_sub_return arch_atomic64_sub_return
 
 static inline s64 arch_atomic64_fetch_add(s64 i, atomic64_t *v)
 {
 	return xadd(&v->counter, i);
 }
+#define arch_atomic64_fetch_add arch_atomic64_fetch_add
 
 static inline s64 arch_atomic64_fetch_sub(s64 i, atomic64_t *v)
 {
 	return xadd(&v->counter, -i);
 }
+#define arch_atomic64_fetch_sub arch_atomic64_fetch_sub
 
 static inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new)
 {
 	return arch_cmpxchg(&v->counter, old, new);
 }
+#define arch_atomic64_cmpxchg arch_atomic64_cmpxchg
 
-#define arch_atomic64_try_cmpxchg arch_atomic64_try_cmpxchg
 static __always_inline bool arch_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new)
 {
 	return try_cmpxchg(&v->counter, old, new);
 }
+#define arch_atomic64_try_cmpxchg arch_atomic64_try_cmpxchg
 
 static inline s64 arch_atomic64_xchg(atomic64_t *v, s64 new)
 {
 	return arch_xchg(&v->counter, new);
 }
+#define arch_atomic64_xchg arch_atomic64_xchg
 
 static inline void arch_atomic64_and(s64 i, atomic64_t *v)
 {
@@ -207,6 +213,7 @@ static inline s64 arch_atomic64_fetch_and(s64 i, atomic64_t *v)
 	} while (!arch_atomic64_try_cmpxchg(v, &val, val & i));
 	return val;
 }
+#define arch_atomic64_fetch_and arch_atomic64_fetch_and
 
 static inline void arch_atomic64_or(s64 i, atomic64_t *v)
 {
@@ -224,6 +231,7 @@ static inline s64 arch_atomic64_fetch_or(s64 i, atomic64_t *v)
 	} while (!arch_atomic64_try_cmpxchg(v, &val, val | i));
 	return val;
 }
+#define arch_atomic64_fetch_or arch_atomic64_fetch_or
 
 static inline void arch_atomic64_xor(s64 i, atomic64_t *v)
 {
@@ -241,5 +249,6 @@ static inline s64 arch_atomic64_fetch_xor(s64 i, atomic64_t *v)
 	} while (!arch_atomic64_try_cmpxchg(v, &val, val ^ i));
 	return val;
 }
+#define arch_atomic64_fetch_xor arch_atomic64_fetch_xor
 
 #endif /* _ASM_X86_ATOMIC64_64_H */