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(sizeof(struct handler_cb), MYF(MY_WME));
54 if (!*cb)
55 result= TRUE;
56 else
57 {
58 (*cb)->next= NULL;
59 (*cb)->action= action;
60 (*cb)->data= data;
61 }
62 mysql_cond_signal(&COND_manager);
63 mysql_mutex_unlock(&LOCK_manager);
64 return result;
65 }
66
handle_manager(void * arg)67 pthread_handler_t handle_manager(void *arg __attribute__((unused)))
68 {
69 int error = 0;
70 struct timespec abstime;
71 bool reset_flush_time = TRUE;
72 my_thread_init();
73 DBUG_ENTER("handle_manager");
74
75 pthread_detach_this_thread();
76 manager_thread = pthread_self();
77 mysql_mutex_lock(&LOCK_manager);
78 while (!abort_manager)
79 {
80 /* XXX: This will need to be made more general to handle different
81 * polling needs. */
82 if (flush_time)
83 {
84 if (reset_flush_time)
85 {
86 set_timespec(abstime, flush_time);
87 reset_flush_time = FALSE;
88 }
89 while ((!error || error == EINTR) && !abort_manager && !cb_list)
90 error= mysql_cond_timedwait(&COND_manager, &LOCK_manager, &abstime);
91
92 if (error == ETIMEDOUT || error == ETIME)
93 {
94 tc_purge();
95 error = 0;
96 reset_flush_time = TRUE;
97 }
98 }
99 else
100 {
101 while ((!error || error == EINTR) && !abort_manager && !cb_list)
102 error= mysql_cond_wait(&COND_manager, &LOCK_manager);
103 }
104
105 struct handler_cb *cb= cb_list;
106 cb_list= NULL;
107 mysql_mutex_unlock(&LOCK_manager);
108
109 while (cb)
110 {
111 struct handler_cb *next= cb->next;
112 cb->action(cb->data);
113 my_free(cb);
114 cb= next;
115 }
116 mysql_mutex_lock(&LOCK_manager);
117 }
118 manager_thread_in_use = 0;
119 mysql_mutex_unlock(&LOCK_manager);
120 mysql_mutex_destroy(&LOCK_manager);
121 mysql_cond_destroy(&COND_manager);
122 DBUG_LEAVE; // Can't use DBUG_RETURN after my_thread_end
123 my_thread_end();
124 return (NULL);
125 }
126
127
128 /* Start handle manager thread */
start_handle_manager()129 void start_handle_manager()
130 {
131 DBUG_ENTER("start_handle_manager");
132 abort_manager = false;
133 {
134 pthread_t hThread;
135 int err;
136 manager_thread_in_use = 1;
137 mysql_cond_init(key_COND_manager, &COND_manager,NULL);
138 mysql_mutex_init(key_LOCK_manager, &LOCK_manager, NULL);
139 if ((err= mysql_thread_create(key_thread_handle_manager, &hThread,
140 &connection_attrib, handle_manager, 0)))
141 sql_print_warning("Can't create handle_manager thread (errno: %M)", err);
142 }
143 DBUG_VOID_RETURN;
144 }
145
146
147 /* Initiate shutdown of handle manager thread */
stop_handle_manager()148 void stop_handle_manager()
149 {
150 DBUG_ENTER("stop_handle_manager");
151 if (manager_thread_in_use)
152 {
153 mysql_mutex_lock(&LOCK_manager);
154 abort_manager = true;
155 DBUG_PRINT("quit", ("initiate shutdown of handle manager thread: %lu",
156 (ulong)manager_thread));
157 mysql_cond_signal(&COND_manager);
158 mysql_mutex_unlock(&LOCK_manager);
159 }
160 DBUG_VOID_RETURN;
161 }
162
163