diff options
Diffstat (limited to 'innobase')
| -rw-r--r-- | innobase/include/trx0trx.h | 6 | ||||
| -rw-r--r-- | innobase/lock/lock0lock.c | 34 | ||||
| -rw-r--r-- | innobase/trx/trx0trx.c | 4 |
3 files changed, 41 insertions, 3 deletions
diff --git a/innobase/include/trx0trx.h b/innobase/include/trx0trx.h index 71269cb1e4e..07d5e5a8215 100644 --- a/innobase/include/trx0trx.h +++ b/innobase/include/trx0trx.h @@ -275,13 +275,15 @@ trx_commit_step( que_thr_t* thr); /* in: query thread */ /************************************************************************** Prints info about a transaction to the standard output. The caller must -own the kernel mutex. */ +own the kernel mutex and must have called +innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL or +InnoDB cannot meanwhile change the info printed here. */ void trx_print( /*======*/ FILE* f, /* in: output stream */ - trx_t* trx); /* in: transaction */ + trx_t* trx); /* in: transaction */ /* Signal to a transaction */ diff --git a/innobase/lock/lock0lock.c b/innobase/lock/lock0lock.c index 4343496f6e1..791b81366b2 100644 --- a/innobase/lock/lock0lock.c +++ b/innobase/lock/lock0lock.c @@ -17,6 +17,32 @@ Created 5/7/1996 Heikki Tuuri #include "dict0mem.h" #include "trx0sys.h" + +/* 2 function prototypes copied from ha_innodb.cc: */ + +/***************************************************************** +If you want to print a thd that is not associated with the current thread, +you must call this function before reserving the InnoDB kernel_mutex, to +protect MySQL from setting thd->query NULL. If you print a thd of the current +thread, we know that MySQL cannot modify thd->query, and it is not necessary +to call this. Call innobase_mysql_end_print_arbitrary_thd() after you release +the kernel_mutex. +NOTE that /mysql/innobase/lock/lock0lock.c must contain the prototype for this +function! */ + +void +innobase_mysql_prepare_print_arbitrary_thd(void); +/*============================================*/ + +/***************************************************************** +Relases the mutex reserved by innobase_mysql_prepare_print_arbitrary_thd(). +NOTE that /mysql/innobase/lock/lock0lock.c must contain the prototype for this +function! */ + +void +innobase_mysql_end_print_arbitrary_thd(void); +/*========================================*/ + /* Restricts the length of search we will do in the waits-for graph of transactions */ #define LOCK_MAX_N_STEPS_IN_DEADLOCK_CHECK 1000000 @@ -3974,6 +4000,11 @@ lock_print_info( ulint i; mtr_t mtr; + /* We must protect the MySQL thd->query field with a MySQL mutex, and + because the MySQL mutex must be reserved before the kernel_mutex of + InnoDB, we call innobase_mysql_prepare_print_arbitrary_thd() here. */ + + innobase_mysql_prepare_print_arbitrary_thd(); lock_mutex_enter_kernel(); if (lock_deadlock_found) { @@ -4037,6 +4068,7 @@ loop: if (trx == NULL) { lock_mutex_exit_kernel(); + innobase_mysql_end_print_arbitrary_thd(); ut_ad(lock_validate()); @@ -4101,6 +4133,7 @@ loop: if (load_page_first) { lock_mutex_exit_kernel(); + innobase_mysql_end_print_arbitrary_thd(); mtr_start(&mtr); @@ -4110,6 +4143,7 @@ loop: load_page_first = FALSE; + innobase_mysql_prepare_print_arbitrary_thd(); lock_mutex_enter_kernel(); goto loop; diff --git a/innobase/trx/trx0trx.c b/innobase/trx/trx0trx.c index 69cd6c7b22d..335e1f69228 100644 --- a/innobase/trx/trx0trx.c +++ b/innobase/trx/trx0trx.c @@ -1562,7 +1562,9 @@ trx_mark_sql_stat_end( /************************************************************************** Prints info about a transaction to the standard output. The caller must -own the kernel mutex. */ +own the kernel mutex and must have called +innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL or +InnoDB cannot meanwhile change the info printed here. */ void trx_print( |