1 /* Copyright (c) 2000, 2010, 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 #ifdef __cplusplus 28 extern "C" { 29 #endif 30 31 #include <my_pthread.h> 32 #include <my_list.h> 33 34 struct st_thr_lock; 35 extern ulong locks_immediate,locks_waited ; 36 37 /* 38 Important: if a new lock type is added, a matching lock description 39 must be added to sql_test.cc's lock_descriptions array. 40 */ 41 enum thr_lock_type { TL_IGNORE=-1, 42 TL_UNLOCK, /* UNLOCK ANY LOCK */ 43 /* 44 Parser only! At open_tables() becomes TL_READ or 45 TL_READ_NO_INSERT depending on the binary log format 46 (SBR/RBR) and on the table category (log table). 47 Used for tables that are read by statements which 48 modify tables. 49 */ 50 TL_READ_DEFAULT, 51 TL_READ, /* Read lock */ 52 TL_READ_WITH_SHARED_LOCKS, 53 /* High prior. than TL_WRITE. Allow concurrent insert */ 54 TL_READ_HIGH_PRIORITY, 55 /* READ, Don't allow concurrent insert */ 56 TL_READ_NO_INSERT, 57 /* 58 Write lock, but allow other threads to read / write. 59 Used by BDB tables in MySQL to mark that someone is 60 reading/writing to the table. 61 */ 62 TL_WRITE_ALLOW_WRITE, 63 /* 64 WRITE lock used by concurrent insert. Will allow 65 READ, if one could use concurrent insert on table. 66 */ 67 TL_WRITE_CONCURRENT_INSERT, 68 /* Write used by INSERT DELAYED. Allows READ locks */ 69 TL_WRITE_DELAYED, 70 /* 71 parser only! Late bound low_priority flag. 72 At open_tables() becomes thd->update_lock_default. 73 */ 74 TL_WRITE_DEFAULT, 75 /* WRITE lock that has lower priority than TL_READ */ 76 TL_WRITE_LOW_PRIORITY, 77 /* Normal WRITE lock */ 78 TL_WRITE, 79 /* Abort new lock request with an error */ 80 TL_WRITE_ONLY}; 81 82 enum enum_thr_lock_result { THR_LOCK_SUCCESS= 0, THR_LOCK_ABORTED= 1, 83 THR_LOCK_WAIT_TIMEOUT= 2, THR_LOCK_DEADLOCK= 3 }; 84 85 86 extern ulong max_write_lock_count; 87 extern my_bool thr_lock_inited; 88 extern enum thr_lock_type thr_upgraded_concurrent_insert_lock; 89 90 /* 91 A description of the thread which owns the lock. The address 92 of an instance of this structure is used to uniquely identify the thread. 93 */ 94 95 typedef struct st_thr_lock_info 96 { 97 pthread_t thread; 98 my_thread_id thread_id; 99 } THR_LOCK_INFO; 100 101 102 typedef struct st_thr_lock_data { 103 THR_LOCK_INFO *owner; 104 struct st_thr_lock_data *next,**prev; 105 struct st_thr_lock *lock; 106 mysql_cond_t *cond; 107 enum thr_lock_type type; 108 void *status_param; /* Param to status functions */ 109 void *debug_print_param; 110 struct PSI_table *m_psi; 111 } THR_LOCK_DATA; 112 113 struct st_lock_list { 114 THR_LOCK_DATA *data,**last; 115 }; 116 117 typedef struct st_thr_lock { 118 LIST list; 119 mysql_mutex_t mutex; 120 struct st_lock_list read_wait; 121 struct st_lock_list read; 122 struct st_lock_list write_wait; 123 struct st_lock_list write; 124 /* write_lock_count is incremented for write locks and reset on read locks */ 125 ulong write_lock_count; 126 uint read_no_write_count; 127 void (*get_status)(void*, int); /* When one gets a lock */ 128 void (*copy_status)(void*,void*); 129 void (*update_status)(void*); /* Before release of write */ 130 void (*restore_status)(void*); /* Before release of read */ 131 my_bool (*check_status)(void *); 132 } THR_LOCK; 133 134 135 extern LIST *thr_lock_thread_list; 136 extern mysql_mutex_t THR_LOCK_lock; 137 138 my_bool init_thr_lock(void); /* Must be called once/thread */ 139 void thr_lock_info_init(THR_LOCK_INFO *info); 140 void thr_lock_init(THR_LOCK *lock); 141 void thr_lock_delete(THR_LOCK *lock); 142 void thr_lock_data_init(THR_LOCK *lock,THR_LOCK_DATA *data, 143 void *status_param); 144 enum enum_thr_lock_result thr_lock(THR_LOCK_DATA *data, 145 THR_LOCK_INFO *owner, 146 enum thr_lock_type lock_type, 147 ulong lock_wait_timeout); 148 void thr_unlock(THR_LOCK_DATA *data); 149 enum enum_thr_lock_result thr_multi_lock(THR_LOCK_DATA **data, 150 uint count, THR_LOCK_INFO *owner, 151 ulong lock_wait_timeout); 152 void thr_multi_unlock(THR_LOCK_DATA **data,uint count); 153 void 154 thr_lock_merge_status(THR_LOCK_DATA **data, uint count); 155 void thr_abort_locks(THR_LOCK *lock, my_bool upgrade_lock); 156 my_bool thr_abort_locks_for_thread(THR_LOCK *lock, my_thread_id thread); 157 void thr_print_locks(void); /* For debugging */ 158 my_bool thr_upgrade_write_delay_lock(THR_LOCK_DATA *data, 159 enum thr_lock_type new_lock_type, 160 ulong lock_wait_timeout); 161 void thr_downgrade_write_lock(THR_LOCK_DATA *data, 162 enum thr_lock_type new_lock_type); 163 my_bool thr_reschedule_write_lock(THR_LOCK_DATA *data, 164 ulong lock_wait_timeout); 165 void thr_set_lock_wait_callback(void (*before_wait)(void), 166 void (*after_wait)(void)); 167 #ifdef __cplusplus 168 } 169 #endif 170 #endif /* _thr_lock_h */ 171