1 /*-
2 * Copyright (c) 2017 Mark Johnston <[email protected]>
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 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/lock.h>
30 #include <sys/mutex.h>
31 #include <sys/time.h>
32
33 #include <machine/cpu.h>
34
35 #include <linux/hrtimer.h>
36
37 static void
hrtimer_call_handler(void * arg)38 hrtimer_call_handler(void *arg)
39 {
40 struct hrtimer *hrtimer;
41 enum hrtimer_restart ret;
42
43 hrtimer = arg;
44 ret = hrtimer->function(hrtimer);
45
46 if (ret == HRTIMER_RESTART) {
47 callout_schedule_sbt(&hrtimer->callout,
48 nstosbt(hrtimer->expires), nstosbt(hrtimer->precision), 0);
49 } else {
50 callout_deactivate(&hrtimer->callout);
51 }
52 }
53
54 bool
linux_hrtimer_active(struct hrtimer * hrtimer)55 linux_hrtimer_active(struct hrtimer *hrtimer)
56 {
57 bool ret;
58
59 mtx_lock(&hrtimer->mtx);
60 ret = callout_active(&hrtimer->callout);
61 mtx_unlock(&hrtimer->mtx);
62
63 return (ret);
64 }
65
66 /*
67 * Try to cancel active hrtimer.
68 * Return 1 if timer was active and cancellation succeeded, 0 if timer was
69 * inactive, or -1 if the timer is being serviced and can't be cancelled.
70 */
71 int
linux_hrtimer_try_to_cancel(struct hrtimer * hrtimer)72 linux_hrtimer_try_to_cancel(struct hrtimer *hrtimer)
73 {
74 int ret;
75
76 mtx_lock(&hrtimer->mtx);
77 ret = callout_stop(&hrtimer->callout);
78 mtx_unlock(&hrtimer->mtx);
79 if (ret > 0) {
80 return (1);
81 } else if (ret < 0) {
82 return (0);
83 } else {
84 return (-1);
85 }
86 }
87
88 /*
89 * Cancel active hrtimer.
90 * Return 1 if timer was active and cancellation succeeded, or 0 otherwise.
91 */
92 int
linux_hrtimer_cancel(struct hrtimer * hrtimer)93 linux_hrtimer_cancel(struct hrtimer *hrtimer)
94 {
95
96 return (callout_drain(&hrtimer->callout) > 0);
97 }
98
99 void
linux_hrtimer_init(struct hrtimer * hrtimer)100 linux_hrtimer_init(struct hrtimer *hrtimer)
101 {
102
103 memset(hrtimer, 0, sizeof(*hrtimer));
104 mtx_init(&hrtimer->mtx, "hrtimer", NULL,
105 MTX_DEF | MTX_RECURSE | MTX_NOWITNESS);
106 callout_init_mtx(&hrtimer->callout, &hrtimer->mtx, 0);
107 }
108
109 void
linux_hrtimer_set_expires(struct hrtimer * hrtimer,ktime_t time)110 linux_hrtimer_set_expires(struct hrtimer *hrtimer, ktime_t time)
111 {
112 hrtimer->expires = ktime_to_ns(time);
113 }
114
115 void
linux_hrtimer_start(struct hrtimer * hrtimer,ktime_t time)116 linux_hrtimer_start(struct hrtimer *hrtimer, ktime_t time)
117 {
118
119 linux_hrtimer_start_range_ns(hrtimer, time, 0);
120 }
121
122 void
linux_hrtimer_start_range_ns(struct hrtimer * hrtimer,ktime_t time,int64_t nsec)123 linux_hrtimer_start_range_ns(struct hrtimer *hrtimer, ktime_t time,
124 int64_t nsec)
125 {
126
127 mtx_lock(&hrtimer->mtx);
128 hrtimer->precision = nsec;
129 callout_reset_sbt(&hrtimer->callout, nstosbt(ktime_to_ns(time)),
130 nstosbt(nsec), hrtimer_call_handler, hrtimer, 0);
131 mtx_unlock(&hrtimer->mtx);
132 }
133
134 void
linux_hrtimer_forward_now(struct hrtimer * hrtimer,ktime_t interval)135 linux_hrtimer_forward_now(struct hrtimer *hrtimer, ktime_t interval)
136 {
137
138 mtx_lock(&hrtimer->mtx);
139 callout_reset_sbt(&hrtimer->callout, nstosbt(ktime_to_ns(interval)),
140 nstosbt(hrtimer->precision), hrtimer_call_handler, hrtimer, 0);
141 mtx_unlock(&hrtimer->mtx);
142 }
143