Root/
1 | /* |
2 | * net/tipc/handler.c: TIPC signal handling |
3 | * |
4 | * Copyright (c) 2000-2006, Ericsson AB |
5 | * Copyright (c) 2005, Wind River Systems |
6 | * All rights reserved. |
7 | * |
8 | * Redistribution and use in source and binary forms, with or without |
9 | * modification, are permitted provided that the following conditions are met: |
10 | * |
11 | * 1. Redistributions of source code must retain the above copyright |
12 | * notice, this list of conditions and the following disclaimer. |
13 | * 2. Redistributions in binary form must reproduce the above copyright |
14 | * notice, this list of conditions and the following disclaimer in the |
15 | * documentation and/or other materials provided with the distribution. |
16 | * 3. Neither the names of the copyright holders nor the names of its |
17 | * contributors may be used to endorse or promote products derived from |
18 | * this software without specific prior written permission. |
19 | * |
20 | * Alternatively, this software may be distributed under the terms of the |
21 | * GNU General Public License ("GPL") version 2 as published by the Free |
22 | * Software Foundation. |
23 | * |
24 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
25 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
28 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
29 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
30 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
31 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
32 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
33 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
34 | * POSSIBILITY OF SUCH DAMAGE. |
35 | */ |
36 | |
37 | #include "core.h" |
38 | |
39 | struct queue_item { |
40 | struct list_head next_signal; |
41 | void (*handler) (unsigned long); |
42 | unsigned long data; |
43 | }; |
44 | |
45 | static struct kmem_cache *tipc_queue_item_cache; |
46 | static struct list_head signal_queue_head; |
47 | static DEFINE_SPINLOCK(qitem_lock); |
48 | static int handler_enabled; |
49 | |
50 | static void process_signal_queue(unsigned long dummy); |
51 | |
52 | static DECLARE_TASKLET_DISABLED(tipc_tasklet, process_signal_queue, 0); |
53 | |
54 | |
55 | unsigned int tipc_k_signal(Handler routine, unsigned long argument) |
56 | { |
57 | struct queue_item *item; |
58 | |
59 | if (!handler_enabled) { |
60 | err("Signal request ignored by handler\n"); |
61 | return -ENOPROTOOPT; |
62 | } |
63 | |
64 | spin_lock_bh(&qitem_lock); |
65 | item = kmem_cache_alloc(tipc_queue_item_cache, GFP_ATOMIC); |
66 | if (!item) { |
67 | err("Signal queue out of memory\n"); |
68 | spin_unlock_bh(&qitem_lock); |
69 | return -ENOMEM; |
70 | } |
71 | item->handler = routine; |
72 | item->data = argument; |
73 | list_add_tail(&item->next_signal, &signal_queue_head); |
74 | spin_unlock_bh(&qitem_lock); |
75 | tasklet_schedule(&tipc_tasklet); |
76 | return 0; |
77 | } |
78 | |
79 | static void process_signal_queue(unsigned long dummy) |
80 | { |
81 | struct queue_item *__volatile__ item; |
82 | struct list_head *l, *n; |
83 | |
84 | spin_lock_bh(&qitem_lock); |
85 | list_for_each_safe(l, n, &signal_queue_head) { |
86 | item = list_entry(l, struct queue_item, next_signal); |
87 | list_del(&item->next_signal); |
88 | spin_unlock_bh(&qitem_lock); |
89 | item->handler(item->data); |
90 | spin_lock_bh(&qitem_lock); |
91 | kmem_cache_free(tipc_queue_item_cache, item); |
92 | } |
93 | spin_unlock_bh(&qitem_lock); |
94 | } |
95 | |
96 | int tipc_handler_start(void) |
97 | { |
98 | tipc_queue_item_cache = |
99 | kmem_cache_create("tipc_queue_items", sizeof(struct queue_item), |
100 | 0, SLAB_HWCACHE_ALIGN, NULL); |
101 | if (!tipc_queue_item_cache) |
102 | return -ENOMEM; |
103 | |
104 | INIT_LIST_HEAD(&signal_queue_head); |
105 | tasklet_enable(&tipc_tasklet); |
106 | handler_enabled = 1; |
107 | return 0; |
108 | } |
109 | |
110 | void tipc_handler_stop(void) |
111 | { |
112 | struct list_head *l, *n; |
113 | struct queue_item *item; |
114 | |
115 | if (!handler_enabled) |
116 | return; |
117 | |
118 | handler_enabled = 0; |
119 | tasklet_disable(&tipc_tasklet); |
120 | tasklet_kill(&tipc_tasklet); |
121 | |
122 | spin_lock_bh(&qitem_lock); |
123 | list_for_each_safe(l, n, &signal_queue_head) { |
124 | item = list_entry(l, struct queue_item, next_signal); |
125 | list_del(&item->next_signal); |
126 | kmem_cache_free(tipc_queue_item_cache, item); |
127 | } |
128 | spin_unlock_bh(&qitem_lock); |
129 | |
130 | kmem_cache_destroy(tipc_queue_item_cache); |
131 | } |
132 | |
133 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9