Move all kill mutex protection to LOCK_thd_kill

LOCK_thd_data was used to protect both THD data and
ensure that the THD is not deleted while it was in use

This patch moves the THD delete protection to LOCK_thd_kill,
which already protects the THD for kill.

The benefits are:
- More well defined what LOCK_thd_data protects
- LOCK_thd_data usage is now much simpler and easier to verify
- Less chance of deadlocks in SHOW PROCESS LIST as there is less
  chance of interactions between mutexes
- Remove not needed LOCK_thread_count from
  thd_get_error_context_description()
- Fewer mutex taken for thd->awake()

Other things:
- Don't take mysys->var mutex in show processlist to check if thread
  is kill marked
- thd->awake() now automatically takes the LOCK_thd_kill mutex
  (Simplifies code)
- Apc uses LOCK_thd_kill instead of LOCK_thd_data

1 files changed, 7 insertions, 7 deletions

diff --git a/mysql-test/suite/perfschema/r/nesting.result b/mysql-test/suite/perfschema/r/nesting.result
index 78126d93cc7..37681757973 100644
--- a/mysql-test/suite/perfschema/r/nesting.result
+++ b/mysql-test/suite/perfschema/r/nesting.result
@@ -125,7 +125,7 @@ relative_event_id	relative_end_event_id	event_name	comment	nesting_event_type	re
 15	15	stage/sql/Starting cleanup	(stage)	STATEMENT	0
 16	16	stage/sql/Freeing items	(stage)	STATEMENT	0
 17	17	wait/io/socket/sql/client_connection	send	STATEMENT	0
-18	18	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STATEMENT	0
+18	18	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STATEMENT	0
 19	20	stage/sql/Reset for next command	(stage)	STATEMENT	0
 20	20	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	19
 21	21	idle	idle	NULL	NULL
@@ -147,7 +147,7 @@ relative_event_id	relative_end_event_id	event_name	comment	nesting_event_type	re
 37	37	stage/sql/Starting cleanup	(stage)	STATEMENT	22
 38	38	stage/sql/Freeing items	(stage)	STATEMENT	22
 39	39	wait/io/socket/sql/client_connection	send	STATEMENT	22
-40	40	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STATEMENT	22
+40	40	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STATEMENT	22
 41	42	stage/sql/Reset for next command	(stage)	STATEMENT	22
 42	42	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	41
 43	43	idle	idle	NULL	NULL
@@ -169,7 +169,7 @@ relative_event_id	relative_end_event_id	event_name	comment	nesting_event_type	re
 59	59	stage/sql/Starting cleanup	(stage)	STATEMENT	44
 60	60	stage/sql/Freeing items	(stage)	STATEMENT	44
 61	61	wait/io/socket/sql/client_connection	send	STATEMENT	44
-62	62	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STATEMENT	44
+62	62	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STATEMENT	44
 63	64	stage/sql/Reset for next command	(stage)	STATEMENT	44
 64	64	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	63
 65	65	idle	idle	NULL	NULL
@@ -194,7 +194,7 @@ select "With a third part to make things complete" as payload	NULL	NULL
 82	82	stage/sql/Starting cleanup	(stage)	STATEMENT	66
 83	85	stage/sql/Freeing items	(stage)	STATEMENT	66
 84	84	wait/io/socket/sql/client_connection	send	STAGE	83
-85	85	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	83
+85	85	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STAGE	83
 86	103	statement/sql/select	select "And this is the second part of a multi query" as payload;
 select "With a third part to make things complete" as payload	NULL	NULL
 87	89	stage/sql/Init	(stage)	STATEMENT	86
@@ -213,7 +213,7 @@ select "With a third part to make things complete" as payload	NULL	NULL
 100	100	stage/sql/Starting cleanup	(stage)	STATEMENT	86
 101	103	stage/sql/Freeing items	(stage)	STATEMENT	86
 102	102	wait/io/socket/sql/client_connection	send	STAGE	101
-103	103	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	101
+103	103	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STAGE	101
 104	122	statement/sql/select	select "With a third part to make things complete" as payload	NULL	NULL
 105	106	stage/sql/Init	(stage)	STATEMENT	104
 106	106	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	105
@@ -230,7 +230,7 @@ select "With a third part to make things complete" as payload	NULL	NULL
 117	117	stage/sql/Starting cleanup	(stage)	STATEMENT	104
 118	118	stage/sql/Freeing items	(stage)	STATEMENT	104
 119	119	wait/io/socket/sql/client_connection	send	STATEMENT	104
-120	120	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STATEMENT	104
+120	120	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STATEMENT	104
 121	122	stage/sql/Reset for next command	(stage)	STATEMENT	104
 122	122	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	121
 123	123	idle	idle	NULL	NULL
@@ -252,7 +252,7 @@ select "With a third part to make things complete" as payload	NULL	NULL
 139	139	stage/sql/Starting cleanup	(stage)	STATEMENT	124
 140	140	stage/sql/Freeing items	(stage)	STATEMENT	124
 141	141	wait/io/socket/sql/client_connection	send	STATEMENT	124
-142	142	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STATEMENT	124
+142	142	wait/synch/mutex/sql/THD::LOCK_thd_kill	lock	STATEMENT	124
 143	144	stage/sql/Reset for next command	(stage)	STATEMENT	124
 144	144	wait/synch/mutex/sql/THD::LOCK_thd_data	lock	STAGE	143
 disconnect con1;