diff options
Diffstat (limited to 'storage/maria/trnman.c')
| -rw-r--r-- | storage/maria/trnman.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/storage/maria/trnman.c b/storage/maria/trnman.c index 09c8f9a264f..f523da22291 100644 --- a/storage/maria/trnman.c +++ b/storage/maria/trnman.c @@ -261,6 +261,7 @@ TRN *trnman_new_trn(WT_THD *wt) { int res; TRN *trn; + union { TRN *trn; void *v; } tmp; DBUG_ENTER("trnman_new_trn"); /* @@ -276,19 +277,19 @@ TRN *trnman_new_trn(WT_THD *wt) pthread_mutex_lock(&LOCK_trn_list); /* Allocating a new TRN structure */ - trn= pool; + tmp.trn= pool; /* Popping an unused TRN from the pool (ABA isn't possible, we're behind a mutex */ my_atomic_rwlock_wrlock(&LOCK_pool); - while (trn && !my_atomic_casptr((void **)&pool, (void **)&trn, - (void *)trn->next)) + while (tmp.trn && !my_atomic_casptr((void **)&pool, &tmp.v, + (void *)tmp.trn->next)) /* no-op */; my_atomic_rwlock_wrunlock(&LOCK_pool); /* Nothing in the pool ? Allocate a new one */ - if (!trn) + if (!(trn= tmp.trn)) { /* trn should be completely initalized at create time to allow @@ -359,7 +360,7 @@ TRN *trnman_new_trn(WT_THD *wt) return 0; } - DBUG_PRINT("exit", ("trn: x%lx trid: 0x%lu", + DBUG_PRINT("exit", ("trn: 0x%lx trid: 0x%lu", (ulong) trn, (ulong) trn->trid)); DBUG_RETURN(trn); @@ -385,11 +386,12 @@ TRN *trnman_new_trn(WT_THD *wt) my_bool trnman_end_trn(TRN *trn, my_bool commit) { int res= 1; + uint16 cached_short_id= trn->short_id; /* we have to cache it, see below */ TRN *free_me= 0; LF_PINS *pins= trn->pins; DBUG_ENTER("trnman_end_trn"); + DBUG_PRINT("enter", ("trn=0x%lx commit=%d", (ulong) trn, commit)); - DBUG_ASSERT(trn->rec_lsn == 0); /* if a rollback, all UNDO records should have been executed */ DBUG_ASSERT(commit || trn->undo_lsn == 0); DBUG_PRINT("info", ("pthread_mutex_lock LOCK_trn_list")); @@ -454,11 +456,17 @@ my_bool trnman_end_trn(TRN *trn, my_bool commit) res= -1; trnman_active_transactions--; + DBUG_PRINT("info", ("pthread_mutex_unlock LOCK_trn_list")); pthread_mutex_unlock(&LOCK_trn_list); - /* the rest is done outside of a critical section */ + /* + the rest is done outside of a critical section + + note that we don't own trn anymore, it may be in a shared list now. + Thus, we cannot dereference it, and must use cached_short_id below. + */ my_atomic_rwlock_rdlock(&LOCK_short_trid_to_trn); - my_atomic_storeptr((void **)&short_trid_to_active_trn[trn->short_id], 0); + my_atomic_storeptr((void **)&short_trid_to_active_trn[cached_short_id], 0); my_atomic_rwlock_rdunlock(&LOCK_short_trid_to_trn); /* @@ -503,7 +511,6 @@ void trnman_free_trn(TRN *trn) */ union { TRN *trn; void *v; } tmp; - pthread_mutex_lock(&trn->state_lock); trn->short_id= 0; pthread_mutex_unlock(&trn->state_lock); |