diff options
| -rw-r--r-- | sql/mdl.cc | 53 |
1 files changed, 38 insertions, 15 deletions
diff --git a/sql/mdl.cc b/sql/mdl.cc index 11bd6f6ed16..f67aa2c2de1 100644 --- a/sql/mdl.cc +++ b/sql/mdl.cc @@ -230,25 +230,32 @@ private: Print a list of all locks to DBUG trace to help with debugging */ +const char *dbug_print_mdl(MDL_ticket *mdl_ticket) +{ + thread_local char buffer[256]; + MDL_key *mdl_key= mdl_ticket->get_key(); + my_snprintf(buffer, sizeof(buffer) - 1, "%.*s/%.*s (%s)", + (int) mdl_key->db_name_length(), mdl_key->db_name(), + (int) mdl_key->name_length(), mdl_key->name(), + mdl_ticket->get_type_name()->str); + return buffer; +} + + static int mdl_dbug_print_lock(MDL_ticket *mdl_ticket, void *arg, bool granted) { String *tmp= (String*) arg; - char buffer[128]; - MDL_key *mdl_key= mdl_ticket->get_key(); - size_t length; - length= my_snprintf(buffer, sizeof(buffer)-1, - "\nname: %s db: %.*s key_name: %.*s (%s)", - mdl_ticket->get_type_name()->str, - (int) mdl_key->db_name_length(), mdl_key->db_name(), - (int) mdl_key->name_length(), mdl_key->name(), - granted ? "granted" : "waiting"); + char buffer[256]; + size_t length= my_snprintf(buffer, sizeof(buffer) - 1, + "\n %s (%s)", dbug_print_mdl(mdl_ticket), + granted ? "granted" : "waiting"); tmp->append(buffer, length); return 0; } const char *mdl_dbug_print_locks() { - static String tmp; + thread_local String tmp; mdl_iterate(mdl_dbug_print_lock, (void*) &tmp); return tmp.c_ptr(); } @@ -2268,13 +2275,19 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) MDL_ticket *ticket; MDL_wait::enum_wait_status wait_status; DBUG_ENTER("MDL_context::acquire_lock"); +#ifndef DBUG_OFF + const char *mdl_lock_name= get_mdl_lock_name( + mdl_request->key.mdl_namespace(), mdl_request->type)->str; +#endif DBUG_PRINT("enter", ("lock_type: %s timeout: %f", - get_mdl_lock_name(mdl_request->key.mdl_namespace(), - mdl_request->type)->str, + mdl_lock_name, lock_wait_timeout)); if (try_acquire_lock_impl(mdl_request, &ticket)) + { + DBUG_PRINT("mdl", ("OOM: %s", mdl_lock_name)); DBUG_RETURN(TRUE); + } if (mdl_request->ticket) { @@ -2284,9 +2297,14 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) accordingly, so we can simply return success. */ DBUG_PRINT("info", ("Got lock without waiting")); + DBUG_PRINT("mdl", ("Seized: %s", dbug_print_mdl(mdl_request->ticket))); DBUG_RETURN(FALSE); } +#ifndef DBUG_OFF + const char *ticket_msg= dbug_print_mdl(ticket); +#endif + /* Our attempt to acquire lock without waiting has failed. As a result of this attempt we got MDL_ticket with m_lock @@ -2297,6 +2315,7 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) if (lock_wait_timeout == 0) { + DBUG_PRINT("mdl", ("Nowait: %s", ticket_msg)); mysql_prlock_unlock(&lock->m_rwlock); MDL_ticket::destroy(ticket); my_error(ER_LOCK_WAIT_TIMEOUT, MYF(0)); @@ -2335,6 +2354,7 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) mysql_prlock_unlock(&lock->m_rwlock); + DBUG_PRINT("mdl", ("Waiting: %s", ticket_msg)); will_wait_for(ticket); /* There is a shared or exclusive lock on the object. */ @@ -2387,15 +2407,16 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) switch (wait_status) { case MDL_wait::VICTIM: - DBUG_LOCK_FILE; - DBUG_PRINT("mdl_locks", ("%s", mdl_dbug_print_locks())); - DBUG_UNLOCK_FILE; + DBUG_PRINT("mdl", ("Deadlock: %s", ticket_msg)); + DBUG_PRINT("mdl_locks", ("Existing locks:%s", mdl_dbug_print_locks())); my_error(ER_LOCK_DEADLOCK, MYF(0)); break; case MDL_wait::TIMEOUT: + DBUG_PRINT("mdl", ("Timeout: %s", ticket_msg)); my_error(ER_LOCK_WAIT_TIMEOUT, MYF(0)); break; case MDL_wait::KILLED: + DBUG_PRINT("mdl", ("Killed: %s", ticket_msg)); get_thd()->send_kill_message(); break; default: @@ -2417,6 +2438,7 @@ MDL_context::acquire_lock(MDL_request *mdl_request, double lock_wait_timeout) mdl_request->ticket= ticket; + DBUG_PRINT("mdl", ("Acquired: %s", ticket_msg)); DBUG_RETURN(FALSE); } @@ -2845,6 +2867,7 @@ void MDL_context::release_lock(enum_mdl_duration duration, MDL_ticket *ticket) lock->key.db_name(), lock->key.name())); DBUG_ASSERT(this == ticket->get_ctx()); + DBUG_PRINT("mdl", ("Released: %s", dbug_print_mdl(ticket))); lock->remove_ticket(m_pins, &MDL_lock::m_granted, ticket); |