Manual merge after improving concurrency for key cache reassignment

include/myisam.h:
  Auto merged
isam/isamchk.c:
  Auto merged
myisam/mi_check.c:
  Auto merged
myisam/mi_locking.c:
  Auto merged
myisam/mi_search.c:
  Auto merged
myisam/mi_write.c:
  Auto merged
myisam/myisamchk.c:
  Auto merged
myisam/myisamlog.c:
  Auto merged
mysql-test/r/func_group.result:
  Auto merged
mysys/mf_keycache.c:
  Auto merged
sql/ha_myisam.cc:
  Auto merged
sql/ha_myisam.h:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_lex.cc:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_test.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged

1 files changed, 12 insertions, 2 deletions

diff --git a/myisam/mi_locking.c b/myisam/mi_locking.c
index a707eb294a9..785979235ce 100644
--- a/myisam/mi_locking.c
+++ b/myisam/mi_locking.c
@@ -34,6 +34,7 @@ int mi_lock_database(MI_INFO *info, int lock_type)
   uint count;
   MYISAM_SHARE *share=info->s;
   uint flag;
+  uint switch_fl= 0;
   DBUG_ENTER("mi_lock_database");
   DBUG_PRINT("info",("lock_type: %d", lock_type));
 
@@ -60,12 +61,21 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       else
 	count= --share->w_locks;
       --share->tot_locks;
+      /*
+         During a key cache reassignment the current and registered
+         key caches for the table are different.
+      */ 
       if (info->lock_type == F_WRLCK && !share->w_locks &&
-	  !share->delay_key_write && flush_key_blocks(share->kfile,FLUSH_KEEP))
+	  ((switch_fl= share->keycache != share->reg_keycache) ||
+           !share->delay_key_write) && 
+           flush_key_blocks(*share->keycache, share->kfile,
+                            switch_fl ? FLUSH_REMOVE : FLUSH_KEEP))
       {
 	error=my_errno;
 	mi_mark_crashed(info);		/* Mark that table must be checked */
       }
+      if (switch_fl)
+        share->keycache= share->reg_keycache;
       if (info->opt_flag & (READ_CACHE_USED | WRITE_CACHE_USED))
       {
 	if (end_io_cache(&info->rec_cache))
@@ -400,7 +410,7 @@ int _mi_test_if_changed(register MI_INFO *info)
   {						/* Keyfile has changed */
     DBUG_PRINT("info",("index file changed"));
     if (share->state.process != share->this_process)
-      VOID(flush_key_blocks(share->kfile,FLUSH_RELEASE));
+      VOID(flush_key_blocks(*share->keycache,share->kfile,FLUSH_RELEASE));
     share->last_process=share->state.process;
     info->last_unique=	share->state.unique;
     info->last_loop=	share->state.update_count;