diff options
Diffstat (limited to 'myisam/mi_keycache.c')
| -rw-r--r-- | myisam/mi_keycache.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/myisam/mi_keycache.c b/myisam/mi_keycache.c new file mode 100644 index 00000000000..4b7d7d6b23f --- /dev/null +++ b/myisam/mi_keycache.c @@ -0,0 +1,107 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + +/* + Key cache assignments +*/ + +#include "myisamdef.h" + + +/* + Assign pages of the index file for a table to a key cache + + SYNOPSIS + mi_assign_to_keycache() + info open table + map map of indexes to assign to the key cache + key_cache_ptr pointer to the key cache handle + + RETURN VALUE + 0 if a success. error code - otherwise. + + NOTES. + At present pages for all indexes must be assigned to the same key cache. + In future only pages for indexes specified in the key_map parameter + of the table will be assigned to the specified key cache. +*/ + +typedef struct st_assign_extra_info +{ + pthread_mutex_t *lock; + struct st_my_thread_var *waiting_thread; +} ASSIGN_EXTRA_INFO; + +static void remove_key_cache_assign(void *arg) +{ + KEY_CACHE_VAR *key_cache= (KEY_CACHE_VAR *) arg; + ASSIGN_EXTRA_INFO *extra_info= (ASSIGN_EXTRA_INFO *) key_cache->extra_info; + struct st_my_thread_var *waiting_thread; + pthread_mutex_t *lock= extra_info->lock; + pthread_mutex_lock(lock); + if (!(--key_cache->assignments) && + (waiting_thread = extra_info->waiting_thread)) + { + my_free(extra_info, MYF(0)); + key_cache->extra_info= 0; + if (waiting_thread != my_thread_var) + pthread_cond_signal(&waiting_thread->suspend); + } + pthread_mutex_unlock(lock); +} + +int mi_assign_to_keycache(MI_INFO *info, ulonglong key_map, + KEY_CACHE_VAR *key_cache, + pthread_mutex_t *assign_lock) +{ + ASSIGN_EXTRA_INFO *extra_info; + int error= 0; + MYISAM_SHARE* share= info->s; + + DBUG_ENTER("mi_assign_to_keycache"); + + share->reg_keycache= &key_cache->cache; + pthread_mutex_lock(assign_lock); + if (!(extra_info= (ASSIGN_EXTRA_INFO *) key_cache->extra_info)) + { + if (!(extra_info= (ASSIGN_EXTRA_INFO*) my_malloc(sizeof(ASSIGN_EXTRA_INFO), + MYF(MY_WME | MY_ZEROFILL)))) + DBUG_RETURN(HA_ERR_OUT_OF_MEM); + key_cache->extra_info= extra_info; + key_cache->action= remove_key_cache_assign; + extra_info->lock= assign_lock; + } + key_cache->assignments++; + pthread_mutex_unlock(assign_lock); + + if (!(info->lock_type == F_WRLCK && share->w_locks)) + { + if (flush_key_blocks(*share->keycache, share->kfile, FLUSH_REMOVE)) + { + error=my_errno; + mi_mark_crashed(info); /* Mark that table must be checked */ + } + share->keycache= &key_cache->cache; + } + else + { + extra_info->waiting_thread= my_thread_var; + } + + + DBUG_RETURN(error); +} + |