| Bug #23655 | deadlock in query cache ndb_cache tests with --debug | ||
|---|---|---|---|
| Submitted: | 26 Oct 2006 4:55 | Modified: | 24 Jan 2007 20:52 |
| Reporter: | Stewart Smith | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: General | Severity: | S2 (Serious) |
| Version: | 5.1.13 | OS: | |
| Assigned to: | Stewart Smith | CPU Architecture: | Any |
[26 Oct 2006 7:38]
Tomash Brechko
This bug was introduced with the fix of bug#21051. The bug happens only in debug mode when check_integrity() tries to acquire the lock on a query block that is still locked. There is only one such bogus place, and suggested fix is correct. Thanks for fixing this, Stewart!
[26 Oct 2006 11:13]
Stewart Smith
merging into -ndb trees
[26 Oct 2006 11:43]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/14423 ChangeSet@1.2310, 2006-10-26 21:37:23+10:00, stewart@willster.(none) +1 -0 BUG#23655 deadlock in query cache ndb_cache tests with --debug Deadlock when running ndb_cache tests with --debug. Query cache locks on trying to acquire lock.
[8 Nov 2006 4:11]
Stewart Smith
Pushed to 5.1-ndb
[29 Dec 2006 1:06]
Stewart Smith
probably nothing to document, only affected debug. only 5.1 affected.
[24 Jan 2007 20:52]
Paul DuBois
No changelog entry needed.
Description: Deadlock when running ndb_cache tests with --debug. Query cache locks on trying to acquire lock. Looks like incorrect unlocking order in sql_cache.cc How to repeat: run mysql-test-run.pl --do-test=ndb_cache Suggested fix: ===== sql/sql_cache.cc 1.93 vs edited ===== --- 1.93/sql/sql_cache.cc 2006-10-26 14:49:53 +10:00 +++ edited/sql/sql_cache.cc 2006-10-24 19:54:50 +10:00 @@ -751,11 +751,10 @@ header->result()->type= Query_cache_block::RESULT; header->writer(0); thd->net.query_cache_query= 0; - DBUG_EXECUTE("check_querycache",query_cache.check_integrity(1);); - - STRUCT_UNLOCK(&query_cache.structure_guard_mutex); BLOCK_UNLOCK_WR(query_block); + DBUG_EXECUTE("check_querycache",query_cache.check_integrity(1);); + STRUCT_UNLOCK(&query_cache.structure_guard_mutex); } else {