diff options
| -rw-r--r-- | arch/ia64/include/asm/mutex.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/mutex.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/mutex_32.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/mutex_64.h | 6 | ||||
| -rw-r--r-- | include/asm-generic/mutex-dec.h | 2 | ||||
| -rw-r--r-- | include/asm-generic/mutex-xchg.h | 6 | ||||
| -rw-r--r-- | kernel/rcu/tree.c | 1 |
7 files changed, 12 insertions, 9 deletions
diff --git a/arch/ia64/include/asm/mutex.h b/arch/ia64/include/asm/mutex.h index f41e66d65e31..28cb819e0ff9 100644 --- a/arch/ia64/include/asm/mutex.h +++ b/arch/ia64/include/asm/mutex.h @@ -82,7 +82,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - if (cmpxchg_acq(count, 1, 0) == 1) + if (atomic_read(count) == 1 && cmpxchg_acq(count, 1, 0) == 1) return 1; return 0; } diff --git a/arch/powerpc/include/asm/mutex.h b/arch/powerpc/include/asm/mutex.h index 127ab23e1f6c..078155fa1189 100644 --- a/arch/powerpc/include/asm/mutex.h +++ b/arch/powerpc/include/asm/mutex.h @@ -124,7 +124,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - if (likely(__mutex_cmpxchg_lock(count, 1, 0) == 1)) + if (likely(atomic_read(count) == 1 && __mutex_cmpxchg_lock(count, 1, 0) == 1)) return 1; return 0; } diff --git a/arch/x86/include/asm/mutex_32.h b/arch/x86/include/asm/mutex_32.h index 85e6cda45a02..e9355a84fc67 100644 --- a/arch/x86/include/asm/mutex_32.h +++ b/arch/x86/include/asm/mutex_32.h @@ -101,7 +101,7 @@ static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { /* cmpxchg because it never induces a false contention state. */ - if (likely(atomic_cmpxchg(count, 1, 0) == 1)) + if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1)) return 1; return 0; diff --git a/arch/x86/include/asm/mutex_64.h b/arch/x86/include/asm/mutex_64.h index 07537a44216e..d9850758464e 100644 --- a/arch/x86/include/asm/mutex_64.h +++ b/arch/x86/include/asm/mutex_64.h @@ -118,10 +118,10 @@ do { \ static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - if (likely(atomic_cmpxchg(count, 1, 0) == 1)) + if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1)) return 1; - else - return 0; + + return 0; } #endif /* _ASM_X86_MUTEX_64_H */ diff --git a/include/asm-generic/mutex-dec.h b/include/asm-generic/mutex-dec.h index fd694cfd678a..c54829d3de37 100644 --- a/include/asm-generic/mutex-dec.h +++ b/include/asm-generic/mutex-dec.h @@ -80,7 +80,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - if (likely(atomic_cmpxchg_acquire(count, 1, 0) == 1)) + if (likely(atomic_read(count) == 1 && atomic_cmpxchg_acquire(count, 1, 0) == 1)) return 1; return 0; } diff --git a/include/asm-generic/mutex-xchg.h b/include/asm-generic/mutex-xchg.h index a6b4a7bd6ac9..3269ec4e195f 100644 --- a/include/asm-generic/mutex-xchg.h +++ b/include/asm-generic/mutex-xchg.h @@ -91,8 +91,12 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) static inline int __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) { - int prev = atomic_xchg_acquire(count, 0); + int prev; + if (atomic_read(count) != 1) + return 0; + + prev = atomic_xchg_acquire(count, 0); if (unlikely(prev < 0)) { /* * The lock was marked contended so we must restore that diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c7f1bc4f817c..b7326893221f 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3681,7 +3681,6 @@ static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s) if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s) && (rnp == rnp_root || ULONG_CMP_LT(READ_ONCE(rnp_root->exp_seq_rq), s)) && - !mutex_is_locked(&rsp->exp_mutex) && mutex_trylock(&rsp->exp_mutex)) goto fastpath; |
