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| author | Eugene Kosov <claprix@yandex.ru> | 2017-10-09 22:55:05 +0300 |
|---|---|---|
| committer | Sergey Vojtovich <svoj@mariadb.org> | 2017-10-09 23:55:05 +0400 |
| commit | bbfd18c69102c2831f03f7d9dc5b67bd8556b09a (patch) | |
| tree | 318f62ab3e6b323ea99a53174179c6f23f2cb846 | |
| parent | b3027d4065538425f4a8e71fef1227ef41d10d05 (diff) | |
| download | mariadb-git-bbfd18c69102c2831f03f7d9dc5b67bd8556b09a.tar.gz | |
fix unsynchronized read (#463)
* fix unsynchronized read
* use relaxed atomic instead of seq_cst
| -rw-r--r-- | include/my_atomic.h | 2 | ||||
| -rw-r--r-- | storage/innobase/include/sync0rw.ic | 3 | ||||
| -rw-r--r-- | storage/innobase/include/sync0types.h | 2 |
3 files changed, 6 insertions, 1 deletions
diff --git a/include/my_atomic.h b/include/my_atomic.h index 5860426304e..bcb6005a8c2 100644 --- a/include/my_atomic.h +++ b/include/my_atomic.h @@ -235,12 +235,14 @@ make_atomic_store(ptr) #if SIZEOF_LONG == 4 #define my_atomic_addlong(A,B) my_atomic_add32((int32*) (A), (B)) #define my_atomic_loadlong(A) my_atomic_load32((int32*) (A)) +#define my_atomic_loadlong_explicit(A,O) my_atomic_load32_explicit((int32*) (A), (O)) #define my_atomic_storelong(A,B) my_atomic_store32((int32*) (A), (B)) #define my_atomic_faslong(A,B) my_atomic_fas32((int32*) (A), (B)) #define my_atomic_caslong(A,B,C) my_atomic_cas32((int32*) (A), (int32*) (B), (C)) #else #define my_atomic_addlong(A,B) my_atomic_add64((int64*) (A), (B)) #define my_atomic_loadlong(A) my_atomic_load64((int64*) (A)) +#define my_atomic_loadlong_explicit(A,O) my_atomic_load64_explicit((int64*) (A), (O)) #define my_atomic_storelong(A,B) my_atomic_store64((int64*) (A), (B)) #define my_atomic_faslong(A,B) my_atomic_fas64((int64*) (A), (B)) #define my_atomic_caslong(A,B,C) my_atomic_cas64((int64*) (A), (int64*) (B), (C)) diff --git a/storage/innobase/include/sync0rw.ic b/storage/innobase/include/sync0rw.ic index 21872cc8bee..21d12b744a9 100644 --- a/storage/innobase/include/sync0rw.ic +++ b/storage/innobase/include/sync0rw.ic @@ -213,7 +213,8 @@ rw_lock_lock_word_decr( { lint local_lock_word; - local_lock_word = lock->lock_word; + local_lock_word = my_atomic_loadlint_explicit(&lock->lock_word, + MY_MEMORY_ORDER_RELAXED); while (local_lock_word > threshold) { if (my_atomic_caslint(&lock->lock_word, &local_lock_word, diff --git a/storage/innobase/include/sync0types.h b/storage/innobase/include/sync0types.h index 0c1c9adee45..1f8e245569e 100644 --- a/storage/innobase/include/sync0types.h +++ b/storage/innobase/include/sync0types.h @@ -1163,11 +1163,13 @@ enum rw_lock_flag_t { #ifdef _WIN64 #define my_atomic_addlint(A,B) my_atomic_add64((int64*) (A), (B)) #define my_atomic_loadlint(A) my_atomic_load64((int64*) (A)) +#define my_atomic_loadlint_explicit(A,O) my_atomic_load64_explicit((int64*) (A), (O)) #define my_atomic_storelint(A,B) my_atomic_store64((int64*) (A), (B)) #define my_atomic_caslint(A,B,C) my_atomic_cas64((int64*) (A), (int64*) (B), (C)) #else #define my_atomic_addlint my_atomic_addlong #define my_atomic_loadlint my_atomic_loadlong +#define my_atomic_loadlint_explicit my_atomic_loadlong_explicit #define my_atomic_storelint my_atomic_storelong #define my_atomic_caslint my_atomic_caslong #endif |