1 /* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. 2 Copyright (c) 2017, MariaDB Corporation. 3 4 This program is free software; you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation; version 2 of the License. 7 8 This program is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY; without even the implied warranty of 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 GNU General Public License for more details. 12 13 You should have received a copy of the GNU General Public License 14 along with this program; if not, write to the Free Software 15 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ 16 17 /* For use with thr_lock:s */ 18 19 #ifndef _thr_lock_h 20 #define _thr_lock_h 21 #ifdef __cplusplus 22 extern "C" { 23 #endif 24 #include <my_pthread.h> 25 #include <my_list.h> 26 27 struct st_thr_lock; 28 extern ulong locks_immediate,locks_waited ; 29 30 /* 31 Important: if a new lock type is added, a matching lock description 32 must be added to sql_test.cc's lock_descriptions array. 33 */ 34 enum thr_lock_type { TL_IGNORE=-1, 35 TL_UNLOCK, /* UNLOCK ANY LOCK */ 36 /* 37 Parser only! At open_tables() becomes TL_READ or 38 TL_READ_NO_INSERT depending on the binary log format 39 (SBR/RBR) and on the table category (log table). 40 Used for tables that are read by statements which 41 modify tables. 42 */ 43 TL_READ_DEFAULT, 44 TL_READ, /* Read lock */ 45 TL_READ_WITH_SHARED_LOCKS, 46 /* High prior. than TL_WRITE. Allow concurrent insert */ 47 TL_READ_HIGH_PRIORITY, 48 /* READ, Don't allow concurrent insert */ 49 TL_READ_NO_INSERT, 50 /* 51 Write lock, but allow other threads to read / write. 52 Used by BDB tables in MySQL to mark that someone is 53 reading/writing to the table. 54 */ 55 TL_WRITE_ALLOW_WRITE, 56 /* 57 WRITE lock used by concurrent insert. Will allow 58 READ, if one could use concurrent insert on table. 59 */ 60 TL_WRITE_CONCURRENT_INSERT, 61 /* Write used by INSERT DELAYED. Allows READ locks */ 62 TL_WRITE_DELAYED, 63 /* 64 parser only! Late bound low_priority flag. 65 At open_tables() becomes thd->update_lock_default. 66 */ 67 TL_WRITE_DEFAULT, 68 /* WRITE lock that has lower priority than TL_READ */ 69 TL_WRITE_LOW_PRIORITY, 70 /* Normal WRITE lock */ 71 TL_WRITE, 72 /* Abort new lock request with an error */ 73 TL_WRITE_ONLY}; 74 75 enum enum_thr_lock_result { THR_LOCK_SUCCESS= 0, THR_LOCK_ABORTED= 1, 76 THR_LOCK_WAIT_TIMEOUT= 2, THR_LOCK_DEADLOCK= 3 }; 77 78 79 /* Priority for locks */ 80 #define THR_LOCK_LATE_PRIV 1U /* For locks to be merged with org lock */ 81 #define THR_LOCK_MERGE_PRIV 2U /* For merge tables */ 82 83 #define THR_UNLOCK_UPDATE_STATUS 1U 84 85 extern ulong max_write_lock_count; 86 extern my_bool thr_lock_inited; 87 extern enum thr_lock_type thr_upgraded_concurrent_insert_lock; 88 89 /* 90 A description of the thread which owns the lock. The address 91 of an instance of this structure is used to uniquely identify the thread. 92 */ 93 94 typedef struct st_thr_lock_info 95 { 96 pthread_t thread; 97 my_thread_id thread_id; 98 void *mysql_thd; // THD pointer 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 void *status_param; /* Param to status functions */ 108 void *debug_print_param; /* For error messages */ 109 struct PSI_table *m_psi; 110 enum thr_lock_type type; 111 enum thr_lock_type org_type; /* Cache for MariaDB */ 112 uint priority; 113 } THR_LOCK_DATA; 114 115 struct st_lock_list { 116 THR_LOCK_DATA *data,**last; 117 }; 118 119 typedef struct st_thr_lock { 120 LIST list; 121 mysql_mutex_t mutex; 122 struct st_lock_list read_wait; 123 struct st_lock_list read; 124 struct st_lock_list write_wait; 125 struct st_lock_list write; 126 /* write_lock_count is incremented for write locks and reset on read locks */ 127 ulong write_lock_count; 128 uint read_no_write_count; 129 my_bool (*get_status)(void*, my_bool);/* Called when one gets a lock */ 130 void (*copy_status)(void*,void*); 131 void (*update_status)(void*); /* Before release of write */ 132 void (*restore_status)(void*); /* Before release of read */ 133 my_bool (*start_trans)(void*); /* When all locks are taken */ 134 my_bool (*check_status)(void *); 135 void (*fix_status)(void *, void *);/* For thr_merge_locks() */ 136 const char *name; /* Used for error reporting */ 137 my_bool allow_multiple_concurrent_insert; 138 } THR_LOCK; 139 140 141 extern LIST *thr_lock_thread_list; 142 extern mysql_mutex_t THR_LOCK_lock; 143 struct st_my_thread_var; 144 145 my_bool init_thr_lock(void); /* Must be called once/thread */ 146 void thr_lock_info_init(THR_LOCK_INFO *info, struct st_my_thread_var *tmp); 147 void thr_lock_init(THR_LOCK *lock); 148 void thr_lock_delete(THR_LOCK *lock); 149 void thr_lock_data_init(THR_LOCK *lock,THR_LOCK_DATA *data, 150 void *status_param); 151 void thr_unlock(THR_LOCK_DATA *data, uint unlock_flags); 152 enum enum_thr_lock_result thr_multi_lock(THR_LOCK_DATA **data, 153 uint count, THR_LOCK_INFO *owner, 154 ulong lock_wait_timeout); 155 void thr_multi_unlock(THR_LOCK_DATA **data,uint count, uint unlock_flags); 156 void thr_merge_locks(THR_LOCK_DATA **data, uint org_count, uint new_count); 157 void thr_abort_locks(THR_LOCK *lock, my_bool upgrade_lock); 158 my_bool thr_abort_locks_for_thread(THR_LOCK *lock, my_thread_id thread); 159 void thr_print_locks(void); /* For debugging */ 160 my_bool thr_upgrade_write_delay_lock(THR_LOCK_DATA *data, 161 enum thr_lock_type new_lock_type, 162 ulong lock_wait_timeout); 163 void thr_downgrade_write_lock(THR_LOCK_DATA *data, 164 enum thr_lock_type new_lock_type); 165 my_bool thr_reschedule_write_lock(THR_LOCK_DATA *data, 166 ulong lock_wait_timeout); 167 void thr_set_lock_wait_callback(void (*before_wait)(void), 168 void (*after_wait)(void)); 169 170 #ifdef WITH_WSREP 171 typedef my_bool (* wsrep_thd_is_brute_force_fun)(const MYSQL_THD, my_bool); 172 typedef my_bool(* wsrep_abort_thd_fun)(MYSQL_THD, MYSQL_THD, my_bool); 173 typedef my_bool (* wsrep_on_fun)(const MYSQL_THD); 174 void wsrep_thr_lock_init( 175 wsrep_thd_is_brute_force_fun bf_fun, wsrep_abort_thd_fun abort_fun, 176 my_bool debug, my_bool convert_LOCK_to_trx, wsrep_on_fun on_fun); 177 #endif 178 179 #ifdef __cplusplus 180 } 181 #endif 182 #endif /* _thr_lock_h */ 183