1 /* Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. 2 3 This program is free software; you can redistribute it and/or modify 4 it under the terms of the GNU General Public License, version 2.0, 5 as published by the Free Software Foundation. 6 7 This program is also distributed with certain software (including 8 but not limited to OpenSSL) that is licensed under separate terms, 9 as designated in a particular file or component or in included license 10 documentation. The authors of MySQL hereby grant you an additional 11 permission to link the program and your derivative works with the 12 separately licensed software that they have included with MySQL. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License, version 2.0, for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ 22 23 /* For use with thr_lock:s */ 24 25 #ifndef _thr_lock_h 26 #define _thr_lock_h 27 28 #include <my_thread.h> 29 #include <my_list.h> 30 #include "mysql/psi/mysql_thread.h" 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 struct st_thr_lock; 37 extern ulong locks_immediate,locks_waited ; 38 39 /* 40 Important: if a new lock type is added, a matching lock description 41 must be added to sql_test.cc's lock_descriptions array. 42 */ 43 enum thr_lock_type { TL_IGNORE=-1, 44 TL_UNLOCK, /* UNLOCK ANY LOCK */ 45 /* 46 Parser only! At open_tables() becomes TL_READ or 47 TL_READ_NO_INSERT depending on the binary log format 48 (SBR/RBR) and on the table category (log table). 49 Used for tables that are read by statements which 50 modify tables. 51 */ 52 TL_READ_DEFAULT, 53 TL_READ, /* Read lock */ 54 TL_READ_WITH_SHARED_LOCKS, 55 /* High prior. than TL_WRITE. Allow concurrent insert */ 56 TL_READ_HIGH_PRIORITY, 57 /* READ, Don't allow concurrent insert */ 58 TL_READ_NO_INSERT, 59 /* 60 Write lock, but allow other threads to read / write. 61 Used by BDB tables in MySQL to mark that someone is 62 reading/writing to the table. 63 */ 64 TL_WRITE_ALLOW_WRITE, 65 /* 66 parser only! Late bound low_priority_flag. 67 At open_tables() becomes thd->insert_lock_default. 68 */ 69 TL_WRITE_CONCURRENT_DEFAULT, 70 /* 71 WRITE lock used by concurrent insert. Will allow 72 READ, if one could use concurrent insert on table. 73 */ 74 TL_WRITE_CONCURRENT_INSERT, 75 /* 76 parser only! Late bound low_priority flag. 77 At open_tables() becomes thd->update_lock_default. 78 */ 79 TL_WRITE_DEFAULT, 80 /* WRITE lock that has lower priority than TL_READ */ 81 TL_WRITE_LOW_PRIORITY, 82 /* Normal WRITE lock */ 83 TL_WRITE, 84 /* Abort new lock request with an error */ 85 TL_WRITE_ONLY}; 86 87 enum enum_thr_lock_result { THR_LOCK_SUCCESS= 0, THR_LOCK_ABORTED= 1, 88 THR_LOCK_WAIT_TIMEOUT= 2, THR_LOCK_DEADLOCK= 3 }; 89 90 91 extern ulong max_write_lock_count; 92 extern enum thr_lock_type thr_upgraded_concurrent_insert_lock; 93 94 /* 95 A description of the thread which owns the lock. The address 96 of an instance of this structure is used to uniquely identify the thread. 97 */ 98 99 typedef struct st_thr_lock_info 100 { 101 my_thread_id thread_id; 102 mysql_cond_t *suspend; 103 } THR_LOCK_INFO; 104 105 106 typedef struct st_thr_lock_data { 107 THR_LOCK_INFO *owner; 108 struct st_thr_lock_data *next,**prev; 109 struct st_thr_lock *lock; 110 mysql_cond_t *cond; 111 enum thr_lock_type type; 112 void *status_param; /* Param to status functions */ 113 void *debug_print_param; 114 struct PSI_table *m_psi; 115 } THR_LOCK_DATA; 116 117 struct st_lock_list { 118 THR_LOCK_DATA *data,**last; 119 }; 120 121 typedef struct st_thr_lock { 122 LIST list; 123 mysql_mutex_t mutex; 124 struct st_lock_list read_wait; 125 struct st_lock_list read; 126 struct st_lock_list write_wait; 127 struct st_lock_list write; 128 /* write_lock_count is incremented for write locks and reset on read locks */ 129 ulong write_lock_count; 130 uint read_no_write_count; 131 void (*get_status)(void*, int); /* When one gets a lock */ 132 void (*copy_status)(void*,void*); 133 void (*update_status)(void*); /* Before release of write */ 134 void (*restore_status)(void*); /* Before release of read */ 135 my_bool (*check_status)(void *); 136 } THR_LOCK; 137 138 139 extern LIST *thr_lock_thread_list; 140 extern mysql_mutex_t THR_LOCK_lock; 141 142 void thr_lock_info_init(THR_LOCK_INFO *info, my_thread_id thread_id, 143 mysql_cond_t *suspend); 144 void thr_lock_init(THR_LOCK *lock); 145 void thr_lock_delete(THR_LOCK *lock); 146 void thr_lock_data_init(THR_LOCK *lock,THR_LOCK_DATA *data, 147 void *status_param); 148 enum enum_thr_lock_result thr_lock(THR_LOCK_DATA *data, 149 THR_LOCK_INFO *owner, 150 enum thr_lock_type lock_type, 151 ulong lock_wait_timeout); 152 void thr_unlock(THR_LOCK_DATA *data); 153 enum enum_thr_lock_result thr_multi_lock(THR_LOCK_DATA **data, 154 uint count, THR_LOCK_INFO *owner, 155 ulong lock_wait_timeout); 156 void thr_multi_unlock(THR_LOCK_DATA **data,uint count); 157 void 158 thr_lock_merge_status(THR_LOCK_DATA **data, uint count); 159 void thr_abort_locks(THR_LOCK *lock, my_bool upgrade_lock); 160 void thr_abort_locks_for_thread(THR_LOCK *lock, my_thread_id thread); 161 void thr_print_locks(void); /* For debugging */ 162 void thr_downgrade_write_lock(THR_LOCK_DATA *data, 163 enum thr_lock_type new_lock_type); 164 void thr_set_lock_wait_callback(void (*before_wait)(void), 165 void (*after_wait)(void)); 166 #ifdef __cplusplus 167 } 168 #endif 169 #endif /* _thr_lock_h */ 170