1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
/* Copyright (C) 2007 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Implementation for the thread scheduler
*/
#ifdef USE_PRAGMA_INTERFACE
#pragma implementation
#endif
#include <mysql_priv.h>
/*
'Dummy' functions to be used when we don't need any handling for a scheduler
event
*/
static bool init_dummy(void) {return 0;}
static void post_kill_dummy(THD* thd) {}
static void end_dummy(void) {}
static bool end_thread_dummy(THD *thd, bool cache_thread) { return 0; }
/*
Initialize default scheduler with dummy functions so that setup functions
only need to declare those that are relvant for their usage
*/
scheduler_functions::scheduler_functions()
:init(init_dummy),
init_new_connection_thread(init_new_connection_handler_thread),
add_connection(0), // Must be defined
post_kill_notification(post_kill_dummy),
end_thread(end_thread_dummy), end(end_dummy)
{}
/*
End connection, in case when we are using 'no-threads'
*/
static bool no_threads_end(THD *thd, bool put_in_cache)
{
unlink_thd(thd);
pthread_mutex_unlock(&LOCK_thread_count);
return 1; // Abort handle_one_connection
}
/*
Initailize scheduler for --thread-handling=no-threads
*/
void one_thread_scheduler(scheduler_functions* func)
{
func->max_threads= 1;
#ifndef EMBEDDED_LIBRARY
func->add_connection= handle_connection_in_main_thread;
#endif
func->init_new_connection_thread= init_dummy;
func->end_thread= no_threads_end;
}
/*
Initialize scheduler for --thread-handling=one-thread-per-connection
*/
#ifndef EMBEDDED_LIBRARY
void one_thread_per_connection_scheduler(scheduler_functions* func)
{
func->max_threads= max_connections;
func->add_connection= create_thread_to_handle_connection;
func->end_thread= one_thread_per_connection_end;
}
#endif /* EMBEDDED_LIBRARY */
|