Hi Sanja, JFYI: while reporting this bug I came up with two questions that I couldn't answer quickly. Probably they make sense, if not just ignore them:
1. This code was introduced with https://bugs.launchpad.net/maria/+bug/782223, revision: [email protected] <quot> The callstack leading of "free" containing critical section is: mysqld!free my_no_flags_free Query_cache::free_cache Query_cache::resize fix_query_cache_size set_var::update sql_set_variables mysql_execute_command mysql_parse <quot> It means that this code was supposed to be executed exactly by Query_cache::resize(), where you disable it. Question: if this code is not supposed to be executed by ::resize(), is it needed at all? 2. In Query_cache::resize() I can see block-level locks are acquired with the following comment: <quot> Wait for all readers and writers to exit. When the list of all queries is iterated over with a block level lock, we are done. </quot> Isn't it needed in ::free_cache() also? Regards, Sergey On Sat, Feb 08, 2014 at 01:25:11PM +0000, [email protected] wrote: > At file:///home/bell/maria/bzr/work-maria-5.5-MDEV-5607/ > > ------------------------------------------------------------ > revno: 4056 > revision-id: [email protected] > parent: [email protected] > committer: [email protected] > branch nick: work-maria-5.5-MDEV-5607 > timestamp: Sat 2014-02-08 15:24:48 +0200 > message: > MDEV-5607: Query cache destroys uninitialized rwlock > > - Resize destroyed rw_lock twice, now it is prevented. > - Trash destroyed rw lock. > === modified file 'include/my_valgrind.h' > --- a/include/my_valgrind.h 2012-03-22 11:31:09 +0000 > +++ b/include/my_valgrind.h 2014-02-08 13:24:48 +0000 > @@ -13,7 +13,8 @@ > along with this program; if not, write to the Free Software > Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA > */ > > - > +#ifndef my_valgrind_h > +#define my_valgrind_h > /* Some defines to make it easier to use valgrind */ > #include <m_string.h> /* bfill */ > > @@ -45,3 +46,4 @@ > #define TRASH_FREE(A,B) TRASH_FILL(A,B,0x8F) > #define TRASH(A,B) TRASH_FREE(A,B) > > +#endif //my_valgrind_h > > === modified file 'include/mysql/psi/mysql_thread.h' > --- a/include/mysql/psi/mysql_thread.h 2013-01-11 00:03:43 +0000 > +++ b/include/mysql/psi/mysql_thread.h 2014-02-08 13:24:48 +0000 > @@ -16,6 +16,8 @@ > #ifndef MYSQL_THREAD_H > #define MYSQL_THREAD_H > > +#include <my_valgrind.h> > + > /** > @file mysql/psi/mysql_thread.h > Instrumentation helpers for mysys threads, mutexes, > @@ -714,6 +716,7 @@ static inline int inline_mysql_prlock_in > static inline int inline_mysql_rwlock_destroy( > mysql_rwlock_t *that) > { > + int res; > #ifdef HAVE_PSI_INTERFACE > if (likely(PSI_server && that->m_psi)) > { > @@ -721,7 +724,9 @@ static inline int inline_mysql_rwlock_de > that->m_psi= NULL; > } > #endif > - return rwlock_destroy(&that->m_rwlock); > + res= rwlock_destroy(&that->m_rwlock); > + TRASH(that, sizeof(*that)); > + return res; > } > > #ifndef DISABLE_MYSQL_PRLOCK_H > > === modified file 'mysql-test/r/query_cache.result' > --- a/mysql-test/r/query_cache.result 2013-10-16 13:07:25 +0000 > +++ b/mysql-test/r/query_cache.result 2014-02-08 13:24:48 +0000 > @@ -2077,6 +2077,21 @@ drop procedure p1; > drop table t1; > set GLOBAL query_cache_size=1355776; > SET GLOBAL userstat=default; > +# > +#MDEV-5607 Query cache destroys uninitialized rwlock > +# > +SET @global_query_cache_size = @@global.query_cache_size; > +SET @global_query_cache_type = @@global.query_cache_type; > +SET GLOBAL query_cache_type = default; > +SET GLOBAL query_cache_size = default; > +SET GLOBAL query_cache_type = ON; > +SET GLOBAL query_cache_size = 131072; > +CREATE TABLE t1(a INT); > +SELECT * FROM t1; > +a > +SET GLOBAL query_cache_size = @global_query_cache_size; > +SET GLOBAL query_cache_type = @global_query_cache_type; > +DROP TABLE t1; > End of 5.5 tests > restore defaults > SET GLOBAL query_cache_type= default; > > === modified file 'mysql-test/t/query_cache.test' > --- a/mysql-test/t/query_cache.test 2013-10-16 13:07:25 +0000 > +++ b/mysql-test/t/query_cache.test 2014-02-08 13:24:48 +0000 > @@ -1708,6 +1708,23 @@ drop table t1; > set GLOBAL query_cache_size=1355776; > SET GLOBAL userstat=default; > > +--echo # > +--echo #MDEV-5607 Query cache destroys uninitialized rwlock > +--echo # > +SET @global_query_cache_size = @@global.query_cache_size; > +SET @global_query_cache_type = @@global.query_cache_type; > +SET GLOBAL query_cache_type = default; > +SET GLOBAL query_cache_size = default; > +SET GLOBAL query_cache_type = ON; > +SET GLOBAL query_cache_size = 131072; > + > +CREATE TABLE t1(a INT); > +SELECT * FROM t1; > + > +SET GLOBAL query_cache_size = @global_query_cache_size; > +SET GLOBAL query_cache_type = @global_query_cache_type; > +DROP TABLE t1; > + > --echo End of 5.5 tests > > --echo restore defaults > > === modified file 'sql/sql_cache.cc' > --- a/sql/sql_cache.cc 2013-11-19 12:16:25 +0000 > +++ b/sql/sql_cache.cc 2014-02-08 13:24:48 +0000 > @@ -1326,6 +1326,7 @@ ulong Query_cache::resize(ulong query_ca > query->unlock_n_destroy(); > block= block->next; > } while (block != queries_blocks); > + queries_blocks= NULL; // avoid second destroying by free_cache > } > free_cache(); > > > === modified file 'storage/perfschema/ha_perfschema.cc' > --- a/storage/perfschema/ha_perfschema.cc 2012-03-27 23:04:46 +0000 > +++ b/storage/perfschema/ha_perfschema.cc 2014-02-08 13:24:48 +0000 > @@ -19,9 +19,9 @@ > */ > > #include "my_global.h" > +#include "sql_plugin.h" > #include "my_pthread.h" > #include "my_atomic.h" > -#include "sql_plugin.h" > #include "mysql/plugin.h" > #include "ha_perfschema.h" > #include "pfs_engine_table.h" > > _______________________________________________ > commits mailing list > [email protected] > https://lists.askmonty.org/cgi-bin/mailman/listinfo/commits _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
