diff options
Diffstat (limited to 'storage/innobase/sync/sync0rw.cc')
| -rw-r--r-- | storage/innobase/sync/sync0rw.cc | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/storage/innobase/sync/sync0rw.cc b/storage/innobase/sync/sync0rw.cc index 4ff330791a0..e77c7a9b396 100644 --- a/storage/innobase/sync/sync0rw.cc +++ b/storage/innobase/sync/sync0rw.cc @@ -545,6 +545,8 @@ rw_lock_x_lock_low( const char* file_name,/*!< in: file name where lock requested */ ulint line) /*!< in: line where requested */ { + ibool local_recursive= lock->recursive; + if (rw_lock_lock_word_decr(lock, X_LOCK_DECR)) { /* lock->recursive also tells us if the writer_thread @@ -566,12 +568,12 @@ rw_lock_x_lock_low( } else { os_thread_id_t thread_id = os_thread_get_curr_id(); - if (!pass) { - os_rmb; - } - - /* Decrement failed: relock or failed lock */ - if (!pass && lock->recursive + /* Decrement failed: relock or failed lock + Note: recursive must be loaded before writer_thread see + comment for rw_lock_set_writer_id_and_recursion_flag(). + To achieve this we load it before rw_lock_lock_word_decr(), + which implies full memory barrier in current implementation. */ + if (!pass && local_recursive && os_thread_eq(lock->writer_thread, thread_id)) { /* Relock */ if (lock->lock_word == 0) { |