From 2b625ac3e0b2173df18c69df63af00dd03e8c672 Mon Sep 17 00:00:00 2001 From: Michael Widenius Date: Thu, 23 Feb 2012 16:43:35 +0200 Subject: Fixed lp:933719, "Assertion open_tables == 0 ... " in THD::restore_backup_open_tables_state. This also fixes a (not likely) crashing bug when forcing a thread that was doing a table lock to re-open it's files, for example by creating a trigger. mysys/thr_lock.c: Added more checking to find wrong locks. Removed one, not needed, parameter to thr_lock sql/lock.cc: Fixed mysql_lock_tables() to retry with new sql_lock if lock fails. This was needed as table may be closed and reopened between retry's and then the old sql_lock will point to stale data. sql/mysql_priv.h: Updated prototype sql/sql_base.cc: Ensure that all tables are closed if opening of system table failes; This fixes the assert in THD::restore_backup_open_tables_state sql/sql_handler.cc: Updated variable type --- mysys/thr_lock.c | 41 ++++++++++++++++++++++++++++++----------- 1 file changed, 30 insertions(+), 11 deletions(-) (limited to 'mysys/thr_lock.c') diff --git a/mysys/thr_lock.c b/mysys/thr_lock.c index 99a498cfdd5..32b38105d1f 100644 --- a/mysys/thr_lock.c +++ b/mysys/thr_lock.c @@ -168,7 +168,8 @@ thr_lock_owner_equal(THR_LOCK_OWNER *rhs, THR_LOCK_OWNER *lhs) static uint found_errors=0; static int check_lock(struct st_lock_list *list, const char* lock_type, - const char *where, my_bool same_owner, my_bool no_cond) + const char *where, my_bool same_owner, my_bool no_cond, + my_bool read_lock) { THR_LOCK_DATA *data,**prev; uint count=0; @@ -181,6 +182,23 @@ static int check_lock(struct st_lock_list *list, const char* lock_type, for (data=list->data; data && count++ < MAX_LOCKS ; data=data->next) { + if (data->type == TL_UNLOCK) + { + fprintf(stderr, + "Warning: Found unlocked lock at %s: %s\n", + lock_type, where); + return 1; + } + if ((read_lock && data->type > TL_READ_NO_INSERT) || + (!read_lock && data->type <= TL_READ_NO_INSERT)) + { + fprintf(stderr, + "Warning: Found %s lock in %s queue at %s: %s\n", + read_lock ? "write" : "read", + read_lock ? "read" : "write", + lock_type, where); + return 1; + } if (data->type != last_lock_type) last_lock_type=TL_IGNORE; if (data->prev != prev) @@ -237,11 +255,14 @@ static void check_locks(THR_LOCK *lock, const char *where, if (found_errors < MAX_FOUND_ERRORS) { - if (check_lock(&lock->write,"write",where,1,1) | - check_lock(&lock->write_wait,"write_wait",where,0,0) | - check_lock(&lock->read,"read",where,0,1) | - check_lock(&lock->read_wait,"read_wait",where,0,0)) + if (check_lock(&lock->write,"write",where,1,1,0) | + check_lock(&lock->write_wait,"write_wait",where,0,0,0) | + check_lock(&lock->read,"read",where,0,1,1) | + check_lock(&lock->read_wait,"read_wait",where,0,0,1)) + { + DBUG_ASSERT(my_assert_on_error == 0); found_errors++; + } if (found_errors < MAX_FOUND_ERRORS) { @@ -592,18 +613,17 @@ wait_for_lock(struct st_lock_list *wait, THR_LOCK_DATA *data, static enum enum_thr_lock_result -thr_lock(THR_LOCK_DATA *data, THR_LOCK_OWNER *owner, - enum thr_lock_type lock_type) +thr_lock(THR_LOCK_DATA *data, THR_LOCK_OWNER *owner) { THR_LOCK *lock=data->lock; enum enum_thr_lock_result result= THR_LOCK_SUCCESS; struct st_lock_list *wait_queue; THR_LOCK_DATA *lock_owner; + enum thr_lock_type lock_type= data->type; DBUG_ENTER("thr_lock"); data->next=0; data->cond=0; /* safety */ - data->type=lock_type; data->owner= owner; /* Must be reset ! */ data->priority&= ~THR_LOCK_LATE_PRIV; VOID(pthread_mutex_lock(&lock->mutex)); @@ -912,9 +932,7 @@ void thr_unlock(THR_LOCK_DATA *data, uint unlock_flags) if (lock_type == TL_READ_NO_INSERT) lock->read_no_write_count--; data->type=TL_UNLOCK; /* Mark unlocked */ - check_locks(lock,"after releasing lock", lock_type, 1); wake_up_waiters(lock); - check_locks(lock,"end of thr_unlock", lock_type, 1); pthread_mutex_unlock(&lock->mutex); DBUG_VOID_RETURN; } @@ -934,6 +952,7 @@ static void wake_up_waiters(THR_LOCK *lock) enum thr_lock_type lock_type; DBUG_ENTER("wake_up_waiters"); + check_locks(lock, "before waking up waiters", TL_UNLOCK, 1); if (!lock->write.data) /* If no active write locks */ { data=lock->write_wait.data; @@ -1087,7 +1106,7 @@ thr_multi_lock(THR_LOCK_DATA **data, uint count, THR_LOCK_OWNER *owner) /* lock everything */ for (pos=data,end=data+count; pos < end ; pos++) { - enum enum_thr_lock_result result= thr_lock(*pos, owner, (*pos)->type); + enum enum_thr_lock_result result= thr_lock(*pos, owner); if (result != THR_LOCK_SUCCESS) { /* Aborted */ thr_multi_unlock(data,(uint) (pos-data), 0); -- cgit v1.2.1