xref: /xnu-11215/bsd/net/devtimer.c (revision bb611c8f)
1 /*
2  * Copyright (c) 2004,2007-2008 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 /*
30  * devtimer.c
31  * - timer source based on <kern/thread_call.h>
32  */
33 
34 /*
35  * Modification History:
36  *
37  * June 22, 2004	Dieter Siegmund ([email protected])
38  * - created
39  */
40 #include <sys/param.h>
41 #include <sys/kernel.h>
42 #include <sys/malloc.h>
43 #include <kern/thread_call.h>
44 #include <net/devtimer.h>
45 #include <os/refcnt.h>
46 
47 #ifdef DEVTIMER_DEBUG
48 #define _devtimer_printf        printf
49 #else /* !DEVTIMER_DEBUG */
50 static __inline__ void
51 _devtimer_printf(__unused const char * fmt, ...)
52 {
53 }
54 #endif /* !DEVTIMER_DEBUG */
55 
56 struct devtimer_s {
57 	void *                      dt_callout;
58 	devtimer_timeout_func       dt_timeout_func;
59 	devtimer_process_func       dt_process_func;
60 	void *                      dt_arg0;
61 	void *                      dt_arg1;
62 	void *                      dt_arg2;
63 	int                         dt_generation;
64 	struct os_refcnt            dt_retain_count;
65 };
66 
67 #define M_DEVTIMER      M_DEVBUF
68 
69 static __inline__ void
70 timeval_add(struct timeval tv1, struct timeval tv2,
71     struct timeval * result)
72 {
73 	result->tv_sec = tv1.tv_sec + tv2.tv_sec;
74 	result->tv_usec = tv1.tv_usec + tv2.tv_usec;
75 	if (result->tv_usec > DEVTIMER_USECS_PER_SEC) {
76 		result->tv_usec -= DEVTIMER_USECS_PER_SEC;
77 		result->tv_sec++;
78 	}
79 	return;
80 }
81 
82 static __inline__ uint64_t
83 timeval_to_absolutetime(struct timeval tv)
84 {
85 	uint64_t    secs;
86 	uint64_t    usecs;
87 
88 	clock_interval_to_absolutetime_interval(tv.tv_sec, NSEC_PER_SEC,
89 	    &secs);
90 	clock_interval_to_absolutetime_interval(tv.tv_usec, NSEC_PER_USEC,
91 	    &usecs);
92 	return secs + usecs;
93 }
94 
95 
96 __private_extern__ int
97 devtimer_valid(devtimer_ref timer)
98 {
99 	return timer->dt_callout != NULL;
100 }
101 
102 __private_extern__ void
103 devtimer_retain(devtimer_ref timer)
104 {
105 	os_ref_retain(&timer->dt_retain_count);
106 }
107 
108 __private_extern__ void
109 devtimer_invalidate(devtimer_ref timer)
110 {
111 	devtimer_cancel(timer);
112 	timer->dt_arg0 = NULL;
113 	if (timer->dt_callout != NULL) {
114 		thread_call_free(timer->dt_callout);
115 		timer->dt_callout = NULL;
116 	}
117 	return;
118 }
119 
120 __private_extern__ void
121 devtimer_release(devtimer_ref timer)
122 {
123 	if (os_ref_release(&timer->dt_retain_count) == 0) {
124 		devtimer_invalidate(timer);
125 		FREE(timer, M_DEVTIMER);
126 		_devtimer_printf("devtimer: timer released\n");
127 	}
128 }
129 
130 static void
131 devtimer_process(void * param0, void * param1)
132 {
133 	int                         generation = *(int*)param1;
134 	devtimer_process_func       process_func;
135 	devtimer_timeout_func       timeout_func;
136 	devtimer_ref                timer = (devtimer_ref)param0;
137 
138 	process_func = timer->dt_process_func;
139 	if (process_func != NULL) {
140 		(*process_func)(timer, devtimer_process_func_event_lock);
141 	}
142 	timeout_func = timer->dt_timeout_func;
143 	if (timeout_func != NULL) {
144 		timer->dt_timeout_func = NULL;
145 		if (timer->dt_generation == generation) {
146 			(*timeout_func)(timer->dt_arg0, timer->dt_arg1, timer->dt_arg2);
147 		}
148 	}
149 	devtimer_release(timer);
150 	if (process_func != NULL) {
151 		(*process_func)(timer, devtimer_process_func_event_unlock);
152 	}
153 	return;
154 }
155 
156 __private_extern__ void *
157 devtimer_arg0(devtimer_ref timer)
158 {
159 	return timer->dt_arg0;
160 }
161 
162 __private_extern__ devtimer_ref
163 devtimer_create(devtimer_process_func process_func, void * arg0)
164 {
165 	devtimer_ref        timer;
166 
167 	timer = _MALLOC(sizeof(*timer), M_DEVTIMER, M_WAITOK | M_ZERO);
168 	if (timer == NULL) {
169 		return timer;
170 	}
171 	os_ref_init(&timer->dt_retain_count, NULL);
172 	timer->dt_callout = thread_call_allocate(devtimer_process, timer);
173 	if (timer->dt_callout == NULL) {
174 		_devtimer_printf("devtimer: thread_call_allocate failed\n");
175 		devtimer_release(timer);
176 		timer = NULL;
177 	}
178 	timer->dt_process_func = process_func;
179 	timer->dt_arg0 = arg0;
180 	return timer;
181 }
182 
183 __private_extern__ void
184 devtimer_set_absolute(devtimer_ref timer,
185     struct timeval abs_time,
186     devtimer_timeout_func timeout_func,
187     void * arg1, void * arg2)
188 {
189 	if (timer->dt_callout == NULL) {
190 		printf("devtimer_set_absolute: uninitialized/freed timer\n");
191 		return;
192 	}
193 	devtimer_cancel(timer);
194 	if (timeout_func == NULL) {
195 		return;
196 	}
197 	timer->dt_timeout_func = timeout_func;
198 	timer->dt_arg1 = arg1;
199 	timer->dt_arg2 = arg2;
200 	_devtimer_printf("devtimer: wakeup time is (%d.%d)\n",
201 	    abs_time.tv_sec, abs_time.tv_usec);
202 	timer->dt_generation++;
203 	devtimer_retain(timer);
204 	thread_call_enter1_delayed(timer->dt_callout,
205 	    &timer->dt_generation,
206 	    timeval_to_absolutetime(abs_time));
207 	return;
208 }
209 
210 __private_extern__ void
211 devtimer_set_relative(devtimer_ref timer,
212     struct timeval rel_time,
213     devtimer_timeout_func timeout_func,
214     void * arg1, void * arg2)
215 {
216 	struct timeval              abs_time;
217 	struct timeval              current_time;
218 
219 	current_time = devtimer_current_time();
220 	timeval_add(current_time, rel_time, &abs_time);
221 	devtimer_set_absolute(timer, abs_time, timeout_func, arg1, arg2);
222 	return;
223 }
224 
225 __private_extern__ void
226 devtimer_cancel(devtimer_ref timer)
227 {
228 	if (timer->dt_timeout_func != NULL) {
229 		timer->dt_timeout_func = NULL;
230 		if (timer->dt_callout != NULL) {
231 			_devtimer_printf("devtimer: cancelling timer source\n");
232 			if (thread_call_cancel(timer->dt_callout)) {
233 				devtimer_release(timer);
234 			} else {
235 				_devtimer_printf("devtimer: delayed release\n");
236 			}
237 		}
238 	}
239 	return;
240 }
241 
242 __private_extern__ int
243 devtimer_enabled(devtimer_ref timer)
244 {
245 	return timer->dt_timeout_func != NULL;
246 }
247 
248 __private_extern__ int32_t
249 devtimer_current_secs(void)
250 {
251 	struct timeval      tv;
252 
253 	tv = devtimer_current_time();
254 	return tv.tv_sec;
255 }
256 
257 __private_extern__ struct timeval
258 devtimer_current_time(void)
259 {
260 	struct timeval      tv;
261 	clock_sec_t sec;
262 	clock_usec_t usec;
263 
264 	clock_get_system_microtime(&sec, &usec);
265 	tv.tv_sec = sec;
266 	tv.tv_usec = usec;
267 	return tv;
268 }
269