1 | /* |
---|
2 | * Copyright (c) 2015 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 | #if HAVE_STRUCT__THREAD_QUEUE_QUEUE |
---|
20 | |
---|
21 | #include <sys/lock.h> |
---|
22 | #include <errno.h> |
---|
23 | |
---|
24 | #include <rtems/score/atomic.h> |
---|
25 | #include <rtems/score/chainimpl.h> |
---|
26 | #include <rtems/score/threadimpl.h> |
---|
27 | #include <rtems/score/threadqimpl.h> |
---|
28 | #include <rtems/score/todimpl.h> |
---|
29 | #include <rtems/score/watchdogimpl.h> |
---|
30 | |
---|
31 | #define CONDITION_TQ_OPERATIONS &_Thread_queue_Operations_FIFO |
---|
32 | |
---|
33 | typedef struct { |
---|
34 | Thread_queue_Syslock_queue Queue; |
---|
35 | } Condition_Control; |
---|
36 | |
---|
37 | RTEMS_STATIC_ASSERT( |
---|
38 | offsetof( Condition_Control, Queue ) |
---|
39 | == offsetof( struct _Condition_Control, _Queue ), |
---|
40 | CONDITION_CONTROL_QUEUE |
---|
41 | ); |
---|
42 | |
---|
43 | RTEMS_STATIC_ASSERT( |
---|
44 | sizeof( Condition_Control ) == sizeof( struct _Condition_Control ), |
---|
45 | CONDITION_CONTROL_SIZE |
---|
46 | ); |
---|
47 | |
---|
48 | static Condition_Control *_Condition_Get( |
---|
49 | struct _Condition_Control *_condition |
---|
50 | ) |
---|
51 | { |
---|
52 | return (Condition_Control *) _condition; |
---|
53 | } |
---|
54 | |
---|
55 | static Thread_Control *_Condition_Queue_acquire_critical( |
---|
56 | Condition_Control *condition, |
---|
57 | ISR_lock_Context *lock_context |
---|
58 | ) |
---|
59 | { |
---|
60 | Thread_Control *executing; |
---|
61 | |
---|
62 | executing = _Thread_Executing; |
---|
63 | _Thread_queue_Queue_acquire_critical( |
---|
64 | &condition->Queue.Queue, |
---|
65 | &executing->Potpourri_stats, |
---|
66 | lock_context |
---|
67 | ); |
---|
68 | |
---|
69 | return executing; |
---|
70 | } |
---|
71 | |
---|
72 | static void _Condition_Queue_release( |
---|
73 | Condition_Control *condition, |
---|
74 | ISR_lock_Context *lock_context |
---|
75 | ) |
---|
76 | { |
---|
77 | _Thread_queue_Queue_release( &condition->Queue.Queue, lock_context ); |
---|
78 | } |
---|
79 | |
---|
80 | static Per_CPU_Control *_Condition_Do_wait( |
---|
81 | struct _Condition_Control *_condition, |
---|
82 | Watchdog_Interval timeout, |
---|
83 | ISR_lock_Context *lock_context |
---|
84 | ) |
---|
85 | { |
---|
86 | Condition_Control *condition; |
---|
87 | Thread_Control *executing; |
---|
88 | Per_CPU_Control *cpu_self; |
---|
89 | |
---|
90 | condition = _Condition_Get( _condition ); |
---|
91 | executing = _Condition_Queue_acquire_critical( condition, lock_context ); |
---|
92 | cpu_self = _Thread_Dispatch_disable_critical( lock_context ); |
---|
93 | |
---|
94 | executing->Wait.return_code = 0; |
---|
95 | _Thread_queue_Enqueue_critical( |
---|
96 | &condition->Queue.Queue, |
---|
97 | CONDITION_TQ_OPERATIONS, |
---|
98 | executing, |
---|
99 | STATES_WAITING_FOR_SYS_LOCK_CONDITION, |
---|
100 | timeout, |
---|
101 | ETIMEDOUT, |
---|
102 | lock_context |
---|
103 | ); |
---|
104 | |
---|
105 | return cpu_self; |
---|
106 | } |
---|
107 | |
---|
108 | void _Condition_Wait( |
---|
109 | struct _Condition_Control *_condition, |
---|
110 | struct _Mutex_Control *_mutex |
---|
111 | ) |
---|
112 | { |
---|
113 | ISR_lock_Context lock_context; |
---|
114 | Per_CPU_Control *cpu_self; |
---|
115 | |
---|
116 | _ISR_lock_ISR_disable( &lock_context ); |
---|
117 | cpu_self = _Condition_Do_wait( _condition, 0, &lock_context ); |
---|
118 | |
---|
119 | _Mutex_Release( _mutex ); |
---|
120 | _Thread_Dispatch_enable( cpu_self ); |
---|
121 | _Mutex_Acquire( _mutex ); |
---|
122 | } |
---|
123 | |
---|
124 | int _Condition_Wait_timed( |
---|
125 | struct _Condition_Control *_condition, |
---|
126 | struct _Mutex_Control *_mutex, |
---|
127 | const struct timespec *abstime |
---|
128 | ) |
---|
129 | { |
---|
130 | ISR_lock_Context lock_context; |
---|
131 | Per_CPU_Control *cpu_self; |
---|
132 | Thread_Control *executing; |
---|
133 | int eno; |
---|
134 | Watchdog_Interval ticks; |
---|
135 | |
---|
136 | _ISR_lock_ISR_disable( &lock_context ); |
---|
137 | |
---|
138 | switch ( _TOD_Absolute_timeout_to_ticks( abstime, &ticks ) ) { |
---|
139 | case TOD_ABSOLUTE_TIMEOUT_INVALID: |
---|
140 | _ISR_lock_ISR_enable( &lock_context ); |
---|
141 | return EINVAL; |
---|
142 | case TOD_ABSOLUTE_TIMEOUT_IS_IN_PAST: |
---|
143 | case TOD_ABSOLUTE_TIMEOUT_IS_NOW: |
---|
144 | _ISR_lock_ISR_enable( &lock_context ); |
---|
145 | return ETIMEDOUT; |
---|
146 | default: |
---|
147 | break; |
---|
148 | } |
---|
149 | |
---|
150 | cpu_self = _Condition_Do_wait( _condition, ticks, &lock_context ); |
---|
151 | |
---|
152 | _Mutex_Release( _mutex ); |
---|
153 | executing = cpu_self->executing; |
---|
154 | _Thread_Dispatch_enable( cpu_self ); |
---|
155 | eno = (int) executing->Wait.return_code; |
---|
156 | _Mutex_Acquire( _mutex ); |
---|
157 | |
---|
158 | return eno; |
---|
159 | } |
---|
160 | |
---|
161 | void _Condition_Wait_recursive( |
---|
162 | struct _Condition_Control *_condition, |
---|
163 | struct _Mutex_recursive_Control *_mutex |
---|
164 | ) |
---|
165 | { |
---|
166 | ISR_lock_Context lock_context; |
---|
167 | Per_CPU_Control *cpu_self; |
---|
168 | unsigned int nest_level; |
---|
169 | |
---|
170 | _ISR_lock_ISR_disable( &lock_context ); |
---|
171 | cpu_self = _Condition_Do_wait( _condition, 0, &lock_context ); |
---|
172 | |
---|
173 | nest_level = _mutex->_nest_level; |
---|
174 | _mutex->_nest_level = 0; |
---|
175 | _Mutex_recursive_Release( _mutex ); |
---|
176 | _Thread_Dispatch_enable( cpu_self ); |
---|
177 | _Mutex_recursive_Acquire( _mutex ); |
---|
178 | _mutex->_nest_level = nest_level; |
---|
179 | } |
---|
180 | |
---|
181 | int _Condition_Wait_recursive_timed( |
---|
182 | struct _Condition_Control *_condition, |
---|
183 | struct _Mutex_recursive_Control *_mutex, |
---|
184 | const struct timespec *abstime |
---|
185 | ) |
---|
186 | { |
---|
187 | ISR_lock_Context lock_context; |
---|
188 | Per_CPU_Control *cpu_self; |
---|
189 | Thread_Control *executing; |
---|
190 | int eno; |
---|
191 | unsigned int nest_level; |
---|
192 | Watchdog_Interval ticks; |
---|
193 | |
---|
194 | _ISR_lock_ISR_disable( &lock_context ); |
---|
195 | |
---|
196 | switch ( _TOD_Absolute_timeout_to_ticks( abstime, &ticks ) ) { |
---|
197 | case TOD_ABSOLUTE_TIMEOUT_INVALID: |
---|
198 | _ISR_lock_ISR_enable( &lock_context ); |
---|
199 | return EINVAL; |
---|
200 | case TOD_ABSOLUTE_TIMEOUT_IS_IN_PAST: |
---|
201 | case TOD_ABSOLUTE_TIMEOUT_IS_NOW: |
---|
202 | _ISR_lock_ISR_enable( &lock_context ); |
---|
203 | return ETIMEDOUT; |
---|
204 | default: |
---|
205 | break; |
---|
206 | } |
---|
207 | |
---|
208 | cpu_self = _Condition_Do_wait( _condition, ticks, &lock_context ); |
---|
209 | |
---|
210 | nest_level = _mutex->_nest_level; |
---|
211 | _mutex->_nest_level = 0; |
---|
212 | _Mutex_recursive_Release( _mutex ); |
---|
213 | executing = cpu_self->executing; |
---|
214 | _Thread_Dispatch_enable( cpu_self ); |
---|
215 | eno = (int) executing->Wait.return_code; |
---|
216 | _Mutex_recursive_Acquire( _mutex ); |
---|
217 | _mutex->_nest_level = nest_level; |
---|
218 | |
---|
219 | return eno; |
---|
220 | } |
---|
221 | |
---|
222 | static int _Condition_Wake( struct _Condition_Control *_condition, int count ) |
---|
223 | { |
---|
224 | Condition_Control *condition; |
---|
225 | ISR_lock_Context lock_context; |
---|
226 | Thread_queue_Heads *heads; |
---|
227 | Chain_Control unblock; |
---|
228 | Chain_Node *node; |
---|
229 | Chain_Node *tail; |
---|
230 | int woken; |
---|
231 | |
---|
232 | condition = _Condition_Get( _condition ); |
---|
233 | _ISR_lock_ISR_disable( &lock_context ); |
---|
234 | _Condition_Queue_acquire_critical( condition, &lock_context ); |
---|
235 | |
---|
236 | /* |
---|
237 | * In common uses cases of condition variables there are normally no threads |
---|
238 | * on the queue, so check this condition early. |
---|
239 | */ |
---|
240 | heads = condition->Queue.Queue.heads; |
---|
241 | if ( __predict_true( heads == NULL ) ) { |
---|
242 | _Condition_Queue_release( condition, &lock_context ); |
---|
243 | |
---|
244 | return 0; |
---|
245 | } |
---|
246 | |
---|
247 | woken = 0; |
---|
248 | _Chain_Initialize_empty( &unblock ); |
---|
249 | while ( count > 0 && heads != NULL ) { |
---|
250 | const Thread_queue_Operations *operations; |
---|
251 | Thread_Control *first; |
---|
252 | bool do_unblock; |
---|
253 | |
---|
254 | operations = CONDITION_TQ_OPERATIONS; |
---|
255 | first = ( *operations->first )( heads ); |
---|
256 | |
---|
257 | do_unblock = _Thread_queue_Extract_locked( |
---|
258 | &condition->Queue.Queue, |
---|
259 | operations, |
---|
260 | first |
---|
261 | ); |
---|
262 | if (do_unblock) { |
---|
263 | _Chain_Append_unprotected( &unblock, &first->Wait.Node.Chain ); |
---|
264 | } |
---|
265 | |
---|
266 | ++woken; |
---|
267 | --count; |
---|
268 | heads = condition->Queue.Queue.heads; |
---|
269 | } |
---|
270 | |
---|
271 | node = _Chain_First( &unblock ); |
---|
272 | tail = _Chain_Tail( &unblock ); |
---|
273 | if ( node != tail ) { |
---|
274 | Per_CPU_Control *cpu_self; |
---|
275 | |
---|
276 | cpu_self = _Thread_Dispatch_disable_critical( &lock_context ); |
---|
277 | _Condition_Queue_release( condition, &lock_context ); |
---|
278 | |
---|
279 | do { |
---|
280 | Thread_Control *thread; |
---|
281 | Chain_Node *next; |
---|
282 | |
---|
283 | next = _Chain_Next( node ); |
---|
284 | thread = THREAD_CHAIN_NODE_TO_THREAD( node ); |
---|
285 | _Thread_Timer_remove( thread ); |
---|
286 | _Thread_Unblock( thread ); |
---|
287 | |
---|
288 | node = next; |
---|
289 | } while ( node != tail ); |
---|
290 | |
---|
291 | _Thread_Dispatch_enable( cpu_self ); |
---|
292 | } else { |
---|
293 | _Condition_Queue_release( condition, &lock_context ); |
---|
294 | } |
---|
295 | |
---|
296 | return woken; |
---|
297 | } |
---|
298 | |
---|
299 | void _Condition_Signal( struct _Condition_Control *_condition ) |
---|
300 | { |
---|
301 | _Condition_Wake( _condition, 1 ); |
---|
302 | } |
---|
303 | |
---|
304 | void _Condition_Broadcast( struct _Condition_Control *_condition ) |
---|
305 | { |
---|
306 | _Condition_Wake( _condition, INT_MAX ); |
---|
307 | } |
---|
308 | |
---|
309 | #endif /* HAVE_STRUCT__THREAD_QUEUE_QUEUE */ |
---|