1 | /* |
---|
2 | * Copyright (c) 2015, 2016 embedded brains GmbH. All rights reserved. |
---|
3 | * |
---|
4 | * embedded brains GmbH |
---|
5 | * Dornierstr. 4 |
---|
6 | * 82178 Puchheim |
---|
7 | * Germany |
---|
8 | * <rtems@embedded-brains.de> |
---|
9 | * |
---|
10 | * The license and distribution terms for this file may be |
---|
11 | * found in the file LICENSE in this distribution or at |
---|
12 | * http://www.rtems.org/license/LICENSE. |
---|
13 | */ |
---|
14 | |
---|
15 | #if HAVE_CONFIG_H |
---|
16 | #include "config.h" |
---|
17 | #endif |
---|
18 | |
---|
19 | #include <sys/lock.h> |
---|
20 | #include <errno.h> |
---|
21 | #include <limits.h> |
---|
22 | |
---|
23 | #include <rtems/score/atomic.h> |
---|
24 | #include <rtems/score/chainimpl.h> |
---|
25 | #include <rtems/score/threadimpl.h> |
---|
26 | #include <rtems/score/threadqimpl.h> |
---|
27 | #include <rtems/score/todimpl.h> |
---|
28 | #include <rtems/score/watchdogimpl.h> |
---|
29 | |
---|
30 | #define CONDITION_TQ_OPERATIONS &_Thread_queue_Operations_FIFO |
---|
31 | |
---|
32 | typedef struct { |
---|
33 | Thread_queue_Syslock_queue Queue; |
---|
34 | } Condition_Control; |
---|
35 | |
---|
36 | RTEMS_STATIC_ASSERT( |
---|
37 | offsetof( Condition_Control, Queue ) |
---|
38 | == offsetof( struct _Condition_Control, _Queue ), |
---|
39 | CONDITION_CONTROL_QUEUE |
---|
40 | ); |
---|
41 | |
---|
42 | RTEMS_STATIC_ASSERT( |
---|
43 | sizeof( Condition_Control ) == sizeof( struct _Condition_Control ), |
---|
44 | CONDITION_CONTROL_SIZE |
---|
45 | ); |
---|
46 | |
---|
47 | static Condition_Control *_Condition_Get( |
---|
48 | struct _Condition_Control *_condition |
---|
49 | ) |
---|
50 | { |
---|
51 | return (Condition_Control *) _condition; |
---|
52 | } |
---|
53 | |
---|
54 | static Thread_Control *_Condition_Queue_acquire_critical( |
---|
55 | Condition_Control *condition, |
---|
56 | Thread_queue_Context *queue_context |
---|
57 | ) |
---|
58 | { |
---|
59 | Thread_Control *executing; |
---|
60 | |
---|
61 | executing = _Thread_Executing; |
---|
62 | _Thread_queue_Queue_acquire_critical( |
---|
63 | &condition->Queue.Queue, |
---|
64 | &executing->Potpourri_stats, |
---|
65 | &queue_context->Lock_context.Lock_context |
---|
66 | ); |
---|
67 | |
---|
68 | return executing; |
---|
69 | } |
---|
70 | |
---|
71 | static void _Condition_Queue_release( |
---|
72 | Condition_Control *condition, |
---|
73 | Thread_queue_Context *queue_context |
---|
74 | ) |
---|
75 | { |
---|
76 | _Thread_queue_Queue_release( |
---|
77 | &condition->Queue.Queue, |
---|
78 | &queue_context->Lock_context.Lock_context |
---|
79 | ); |
---|
80 | } |
---|
81 | |
---|
82 | typedef struct { |
---|
83 | Thread_queue_Context Base; |
---|
84 | struct _Mutex_Control *mutex; |
---|
85 | } Condition_Enqueue_context; |
---|
86 | |
---|
87 | static void _Condition_Mutex_release( Thread_queue_Context *queue_context ) |
---|
88 | { |
---|
89 | Condition_Enqueue_context *context; |
---|
90 | |
---|
91 | context = (Condition_Enqueue_context *) queue_context; |
---|
92 | _Mutex_Release( context->mutex ); |
---|
93 | } |
---|
94 | |
---|
95 | static void _Condition_Enqueue_no_timeout( |
---|
96 | Thread_queue_Queue *queue, |
---|
97 | Thread_Control *the_thread, |
---|
98 | Per_CPU_Control *cpu_self, |
---|
99 | Thread_queue_Context *queue_context |
---|
100 | ) |
---|
101 | { |
---|
102 | _Condition_Mutex_release( queue_context ); |
---|
103 | } |
---|
104 | |
---|
105 | static void _Condition_Enqueue_with_timeout( |
---|
106 | Thread_queue_Queue *queue, |
---|
107 | Thread_Control *the_thread, |
---|
108 | Per_CPU_Control *cpu_self, |
---|
109 | Thread_queue_Context *queue_context |
---|
110 | ) |
---|
111 | { |
---|
112 | _Thread_queue_Add_timeout_realtime_timespec( |
---|
113 | queue, |
---|
114 | the_thread, |
---|
115 | cpu_self, |
---|
116 | queue_context |
---|
117 | ); |
---|
118 | _Condition_Mutex_release( queue_context ); |
---|
119 | } |
---|
120 | |
---|
121 | static Thread_Control *_Condition_Do_wait( |
---|
122 | struct _Condition_Control *_condition, |
---|
123 | struct _Mutex_Control *_mutex, |
---|
124 | Condition_Enqueue_context *context |
---|
125 | ) |
---|
126 | { |
---|
127 | Condition_Control *condition; |
---|
128 | Thread_Control *executing; |
---|
129 | |
---|
130 | context->mutex = _mutex; |
---|
131 | condition = _Condition_Get( _condition ); |
---|
132 | _ISR_lock_ISR_disable( &context->Base.Lock_context.Lock_context ); |
---|
133 | executing = _Condition_Queue_acquire_critical( condition, &context->Base ); |
---|
134 | _Thread_queue_Context_set_thread_state( |
---|
135 | &context->Base, |
---|
136 | STATES_WAITING_FOR_CONDITION_VARIABLE |
---|
137 | ); |
---|
138 | _Thread_queue_Enqueue( |
---|
139 | &condition->Queue.Queue, |
---|
140 | CONDITION_TQ_OPERATIONS, |
---|
141 | executing, |
---|
142 | &context->Base |
---|
143 | ); |
---|
144 | |
---|
145 | return executing; |
---|
146 | } |
---|
147 | |
---|
148 | void _Condition_Wait( |
---|
149 | struct _Condition_Control *_condition, |
---|
150 | struct _Mutex_Control *_mutex |
---|
151 | ) |
---|
152 | { |
---|
153 | Condition_Enqueue_context context; |
---|
154 | |
---|
155 | _Thread_queue_Context_initialize( &context.Base ); |
---|
156 | _Thread_queue_Context_set_enqueue_callout( |
---|
157 | &context.Base, |
---|
158 | _Condition_Enqueue_no_timeout |
---|
159 | ); |
---|
160 | _Condition_Do_wait( _condition, _mutex, &context ); |
---|
161 | _Mutex_Acquire( _mutex ); |
---|
162 | } |
---|
163 | |
---|
164 | int _Condition_Wait_timed( |
---|
165 | struct _Condition_Control *_condition, |
---|
166 | struct _Mutex_Control *_mutex, |
---|
167 | const struct timespec *abstime |
---|
168 | ) |
---|
169 | { |
---|
170 | Condition_Enqueue_context context; |
---|
171 | Thread_Control *executing; |
---|
172 | int eno; |
---|
173 | |
---|
174 | _Thread_queue_Context_initialize( &context.Base ); |
---|
175 | _Thread_queue_Context_set_enqueue_callout( |
---|
176 | &context.Base, |
---|
177 | _Condition_Enqueue_with_timeout |
---|
178 | ); |
---|
179 | _Thread_queue_Context_set_timeout_argument( &context.Base, abstime ); |
---|
180 | executing = _Condition_Do_wait( _condition, _mutex, &context ); |
---|
181 | eno = STATUS_GET_POSIX( _Thread_Wait_get_status( executing ) ); |
---|
182 | _Mutex_Acquire( _mutex ); |
---|
183 | |
---|
184 | return eno; |
---|
185 | } |
---|
186 | |
---|
187 | static unsigned int _Condition_Unnest_mutex( |
---|
188 | struct _Mutex_recursive_Control *_mutex |
---|
189 | ) |
---|
190 | { |
---|
191 | unsigned int nest_level; |
---|
192 | |
---|
193 | nest_level = _mutex->_nest_level; |
---|
194 | _mutex->_nest_level = 0; |
---|
195 | |
---|
196 | return nest_level; |
---|
197 | } |
---|
198 | |
---|
199 | void _Condition_Wait_recursive( |
---|
200 | struct _Condition_Control *_condition, |
---|
201 | struct _Mutex_recursive_Control *_mutex |
---|
202 | ) |
---|
203 | { |
---|
204 | Condition_Enqueue_context context; |
---|
205 | unsigned int nest_level; |
---|
206 | |
---|
207 | _Thread_queue_Context_initialize( &context.Base ); |
---|
208 | _Thread_queue_Context_set_enqueue_callout( |
---|
209 | &context.Base, |
---|
210 | _Condition_Enqueue_no_timeout |
---|
211 | ); |
---|
212 | nest_level = _Condition_Unnest_mutex( _mutex ); |
---|
213 | _Condition_Do_wait( _condition, &_mutex->_Mutex, &context ); |
---|
214 | _Mutex_recursive_Acquire( _mutex ); |
---|
215 | _mutex->_nest_level = nest_level; |
---|
216 | } |
---|
217 | |
---|
218 | int _Condition_Wait_recursive_timed( |
---|
219 | struct _Condition_Control *_condition, |
---|
220 | struct _Mutex_recursive_Control *_mutex, |
---|
221 | const struct timespec *abstime |
---|
222 | ) |
---|
223 | { |
---|
224 | Condition_Enqueue_context context; |
---|
225 | Thread_Control *executing; |
---|
226 | int eno; |
---|
227 | unsigned int nest_level; |
---|
228 | |
---|
229 | _Thread_queue_Context_initialize( &context.Base ); |
---|
230 | _Thread_queue_Context_set_enqueue_callout( |
---|
231 | &context.Base, |
---|
232 | _Condition_Enqueue_with_timeout |
---|
233 | ); |
---|
234 | _Thread_queue_Context_set_timeout_argument( &context.Base, abstime ); |
---|
235 | nest_level = _Condition_Unnest_mutex( _mutex ); |
---|
236 | executing = _Condition_Do_wait( _condition, &_mutex->_Mutex, &context ); |
---|
237 | eno = STATUS_GET_POSIX( _Thread_Wait_get_status( executing ) ); |
---|
238 | _Mutex_recursive_Acquire( _mutex ); |
---|
239 | _mutex->_nest_level = nest_level; |
---|
240 | |
---|
241 | return eno; |
---|
242 | } |
---|
243 | |
---|
244 | typedef struct { |
---|
245 | Thread_queue_Context Base; |
---|
246 | int count; |
---|
247 | } Condition_Flush_context; |
---|
248 | |
---|
249 | static Thread_Control *_Condition_Flush_filter( |
---|
250 | Thread_Control *the_thread, |
---|
251 | Thread_queue_Queue *queue, |
---|
252 | Thread_queue_Context *queue_context |
---|
253 | ) |
---|
254 | { |
---|
255 | Condition_Flush_context *context; |
---|
256 | |
---|
257 | context = (Condition_Flush_context *) queue_context; |
---|
258 | |
---|
259 | if ( context->count <= 0 ) { |
---|
260 | return NULL; |
---|
261 | } |
---|
262 | |
---|
263 | --context->count; |
---|
264 | |
---|
265 | return the_thread; |
---|
266 | } |
---|
267 | |
---|
268 | static void _Condition_Wake( struct _Condition_Control *_condition, int count ) |
---|
269 | { |
---|
270 | Condition_Control *condition; |
---|
271 | Condition_Flush_context context; |
---|
272 | |
---|
273 | condition = _Condition_Get( _condition ); |
---|
274 | _Thread_queue_Context_initialize( &context.Base ); |
---|
275 | _ISR_lock_ISR_disable( &context.Base.Lock_context.Lock_context ); |
---|
276 | _Condition_Queue_acquire_critical( condition, &context.Base ); |
---|
277 | |
---|
278 | /* |
---|
279 | * In common uses cases of condition variables there are normally no threads |
---|
280 | * on the queue, so check this condition early. |
---|
281 | */ |
---|
282 | if ( |
---|
283 | RTEMS_PREDICT_TRUE( _Thread_queue_Is_empty( &condition->Queue.Queue ) ) |
---|
284 | ) { |
---|
285 | _Condition_Queue_release( condition, &context.Base ); |
---|
286 | return; |
---|
287 | } |
---|
288 | |
---|
289 | context.count = count; |
---|
290 | _Thread_queue_Flush_critical( |
---|
291 | &condition->Queue.Queue, |
---|
292 | CONDITION_TQ_OPERATIONS, |
---|
293 | _Condition_Flush_filter, |
---|
294 | &context.Base |
---|
295 | ); |
---|
296 | } |
---|
297 | |
---|
298 | void _Condition_Signal( struct _Condition_Control *_condition ) |
---|
299 | { |
---|
300 | _Condition_Wake( _condition, 1 ); |
---|
301 | } |
---|
302 | |
---|
303 | void _Condition_Broadcast( struct _Condition_Control *_condition ) |
---|
304 | { |
---|
305 | _Condition_Wake( _condition, INT_MAX ); |
---|
306 | } |
---|