xref: /freebsd/sys/compat/linuxkpi/common/src/linux_hrtimer.c (revision 47dd1d1b619cc035b82b49a91a25544309ff95ae)
1 /*-
2  * Copyright (c) 2017 Mark Johnston <markj@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice unmodified, this list of conditions, and the following
9  *    disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/lock.h>
32 #include <sys/mutex.h>
33 #include <sys/time.h>
34 
35 #include <machine/cpu.h>
36 
37 #include <linux/hrtimer.h>
38 
39 static void
40 hrtimer_call_handler(void *arg)
41 {
42 	struct hrtimer *hrtimer;
43 	enum hrtimer_restart ret;
44 
45 	hrtimer = arg;
46 	ret = hrtimer->function(hrtimer);
47 	MPASS(ret == HRTIMER_NORESTART);
48 	callout_deactivate(&hrtimer->callout);
49 }
50 
51 bool
52 linux_hrtimer_active(struct hrtimer *hrtimer)
53 {
54 	bool ret;
55 
56 	mtx_lock(&hrtimer->mtx);
57 	ret = callout_active(&hrtimer->callout);
58 	mtx_unlock(&hrtimer->mtx);
59 	return (ret);
60 }
61 
62 /*
63  * Cancel active hrtimer.
64  * Return 1 if timer was active and cancellation succeeded, or 0 otherwise.
65  */
66 int
67 linux_hrtimer_cancel(struct hrtimer *hrtimer)
68 {
69 
70 	return (callout_drain(&hrtimer->callout) > 0);
71 }
72 
73 void
74 linux_hrtimer_init(struct hrtimer *hrtimer)
75 {
76 
77 	hrtimer->function = NULL;
78 	mtx_init(&hrtimer->mtx, "hrtimer", NULL, MTX_DEF | MTX_RECURSE);
79 	callout_init_mtx(&hrtimer->callout, &hrtimer->mtx, 0);
80 }
81 
82 void
83 linux_hrtimer_set_expires(struct hrtimer *hrtimer __unused,
84     ktime_t time __unused)
85 {
86 }
87 
88 void
89 linux_hrtimer_start(struct hrtimer *hrtimer, ktime_t time)
90 {
91 
92 	linux_hrtimer_start_range_ns(hrtimer, time, 0);
93 }
94 
95 void
96 linux_hrtimer_start_range_ns(struct hrtimer *hrtimer, ktime_t time, int64_t nsec)
97 {
98 
99 	mtx_lock(&hrtimer->mtx);
100 	callout_reset_sbt(&hrtimer->callout, nstosbt(time), nstosbt(nsec),
101 	    hrtimer_call_handler, hrtimer, 0);
102 	mtx_unlock(&hrtimer->mtx);
103 }
104