1 /* Copyright (c) 2000, 2013, 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 as published by
5 the Free Software Foundation; version 2 of the License.
6
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11
12 You should have received a copy of the GNU General Public License
13 along with this program; if not, write to the Free Software
14 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
15
16 /*
17 * sql_manager.cc
18 * This thread manages various maintenance tasks.
19 *
20 * o Flushing the tables every flush_time seconds.
21 * o Berkeley DB: removing unneeded log files.
22 */
23
24 #include "mariadb.h"
25 #include "sql_priv.h"
26 #include "sql_manager.h"
27 #include "sql_base.h" // flush_tables
28
29 static bool volatile manager_thread_in_use = 0;
30 static bool abort_manager = false;
31
32 pthread_t manager_thread;
33 mysql_mutex_t LOCK_manager;
34 mysql_cond_t COND_manager;
35
36 struct handler_cb {
37 struct handler_cb *next;
38 void (*action)(void *);
39 void *data;
40 };
41
42 static struct handler_cb *cb_list; // protected by LOCK_manager
43
mysql_manager_submit(void (* action)(void *),void * data)44 bool mysql_manager_submit(void (*action)(void *), void *data)
45 {
46 bool result= FALSE;
47 DBUG_ASSERT(manager_thread_in_use);
48 struct handler_cb **cb;
49 mysql_mutex_lock(&LOCK_manager);
50 cb= &cb_list;
51 while (*cb)
52 cb= &(*cb)->next;
53 *cb= (struct handler_cb *)my_malloc(PSI_INSTRUMENT_ME,
54 sizeof(struct handler_cb), MYF(MY_WME));
55 if (!*cb)
56 result= TRUE;
57 else
58 {
59 (*cb)->next= NULL;
60 (*cb)->action= action;
61 (*cb)->data= data;
62 }
63 mysql_cond_signal(&COND_manager);
64 mysql_mutex_unlock(&LOCK_manager);
65 return result;
66 }
67
handle_manager(void * arg)68 pthread_handler_t handle_manager(void *arg __attribute__((unused)))
69 {
70 int error = 0;
71 struct timespec abstime;
72 bool reset_flush_time = TRUE;
73 my_thread_init();
74 DBUG_ENTER("handle_manager");
75
76 pthread_detach_this_thread();
77 manager_thread = pthread_self();
78 mysql_mutex_lock(&LOCK_manager);
79 while (!abort_manager)
80 {
81 /* XXX: This will need to be made more general to handle different
82 * polling needs. */
83 if (flush_time)
84 {
85 if (reset_flush_time)
86 {
87 set_timespec(abstime, flush_time);
88 reset_flush_time = FALSE;
89 }
90 while ((!error || error == EINTR) && !abort_manager && !cb_list)
91 error= mysql_cond_timedwait(&COND_manager, &LOCK_manager, &abstime);
92
93 if (error == ETIMEDOUT || error == ETIME)
94 {
95 tc_purge();
96 error = 0;
97 reset_flush_time = TRUE;
98 }
99 }
100 else
101 {
102 while ((!error || error == EINTR) && !abort_manager && !cb_list)
103 error= mysql_cond_wait(&COND_manager, &LOCK_manager);
104 }
105
106 struct handler_cb *cb= cb_list;
107 cb_list= NULL;
108 mysql_mutex_unlock(&LOCK_manager);
109
110 while (cb)
111 {
112 struct handler_cb *next= cb->next;
113 cb->action(cb->data);
114 my_free(cb);
115 cb= next;
116 }
117 mysql_mutex_lock(&LOCK_manager);
118 }
119 manager_thread_in_use = 0;
120 mysql_mutex_unlock(&LOCK_manager);
121 mysql_mutex_destroy(&LOCK_manager);
122 mysql_cond_destroy(&COND_manager);
123 DBUG_LEAVE; // Can't use DBUG_RETURN after my_thread_end
124 my_thread_end();
125 return (NULL);
126 }
127
128
129 /* Start handle manager thread */
start_handle_manager()130 void start_handle_manager()
131 {
132 DBUG_ENTER("start_handle_manager");
133 abort_manager = false;
134 {
135 pthread_t hThread;
136 int err;
137 manager_thread_in_use = 1;
138 mysql_cond_init(key_COND_manager, &COND_manager,NULL);
139 mysql_mutex_init(key_LOCK_manager, &LOCK_manager, NULL);
140 if ((err= mysql_thread_create(key_thread_handle_manager, &hThread,
141 &connection_attrib, handle_manager, 0)))
142 sql_print_warning("Can't create handle_manager thread (errno: %M)", err);
143 }
144 DBUG_VOID_RETURN;
145 }
146
147
148 /* Initiate shutdown of handle manager thread */
stop_handle_manager()149 void stop_handle_manager()
150 {
151 DBUG_ENTER("stop_handle_manager");
152 if (manager_thread_in_use)
153 {
154 mysql_mutex_lock(&LOCK_manager);
155 abort_manager = true;
156 DBUG_PRINT("quit", ("initiate shutdown of handle manager thread: %lu",
157 (ulong)manager_thread));
158 mysql_cond_signal(&COND_manager);
159 mysql_mutex_unlock(&LOCK_manager);
160 }
161 DBUG_VOID_RETURN;
162 }
163
164