srv0srv.c:

  Fix a benign bug introduced in 4.0.14: InnoDB could complain 'Error: trying to declare trx to enter InnoDB' if several threads tried to init the auto-inc counter for the same table at the same time; in theory, the bug could even lead to a hang of the server, but that shuld be extremely improbable
parent 2340cff7
......@@ -1739,7 +1739,6 @@ srv_conc_enter_innodb(
trx_t* trx) /* in: transaction object associated with the
thread */
{
ibool has_slept = FALSE;
srv_conc_slot_t* slot;
ulint i;
char err_buf[1000];
......@@ -1758,7 +1757,7 @@ srv_conc_enter_innodb(
return;
}
retry:
os_fast_mutex_lock(&srv_conc_mutex);
if (trx->declared_to_be_inside_innodb) {
......@@ -1769,6 +1768,9 @@ srv_conc_enter_innodb(
fprintf(stderr,
" InnoDB: Error: trying to declare trx to enter InnoDB, but\n"
"InnoDB: it already is declared.\n%s\n", err_buf);
os_fast_mutex_unlock(&srv_conc_mutex);
return;
}
if (srv_conc_n_threads < (lint)srv_thread_concurrency) {
......@@ -1782,22 +1784,6 @@ srv_conc_enter_innodb(
return;
}
/* If the transaction is not holding resources, let it sleep
for 100 milliseconds, and try again then */
if (!has_slept && !trx->has_search_latch
&& NULL == UT_LIST_GET_FIRST(trx->trx_locks)) {
has_slept = TRUE; /* We let is sleep only once to avoid
starvation */
os_fast_mutex_unlock(&srv_conc_mutex);
os_thread_sleep(100000);
goto retry;
}
/* Too many threads inside: put the current thread to a queue */
for (i = 0; i < OS_THREAD_MAX_N; i++) {
......@@ -2111,6 +2097,7 @@ srv_suspend_mysql_thread(
double wait_time;
trx_t* trx;
ibool had_dict_lock = FALSE;
ibool was_declared_inside_innodb = FALSE;
ut_ad(!mutex_own(&kernel_mutex));
......@@ -2158,11 +2145,16 @@ srv_suspend_mysql_thread(
mutex_exit(&kernel_mutex);
/* We must declare this OS thread to exit InnoDB, since a possible
other thread holding a lock which this thread waits for must be
allowed to enter, sooner or later */
if (trx->declared_to_be_inside_innodb) {
was_declared_inside_innodb = TRUE;
srv_conc_force_exit_innodb(thr_get_trx(thr));
/* We must declare this OS thread to exit InnoDB, since a
possible other thread holding a lock which this thread waits
for must be allowed to enter, sooner or later */
srv_conc_force_exit_innodb(trx);
}
/* Release possible foreign key check latch */
if (trx->dict_operation_lock_mode == RW_S_LATCH) {
......@@ -2183,9 +2175,12 @@ srv_suspend_mysql_thread(
row_mysql_freeze_data_dictionary(trx);
}
if (was_declared_inside_innodb) {
/* Return back inside InnoDB */
srv_conc_force_enter_innodb(thr_get_trx(thr));
srv_conc_force_enter_innodb(trx);
}
mutex_enter(&kernel_mutex);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment