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 48 if (ret == HRTIMER_RESTART) { 49 callout_schedule_sbt(&hrtimer->callout, 50 nstosbt(hrtimer->expires), nstosbt(hrtimer->precision), 0); 51 } else { 52 callout_deactivate(&hrtimer->callout); 53 } 54 } 55 56 bool 57 linux_hrtimer_active(struct hrtimer *hrtimer) 58 { 59 bool ret; 60 61 mtx_lock(&hrtimer->mtx); 62 ret = callout_active(&hrtimer->callout); 63 mtx_unlock(&hrtimer->mtx); 64 65 return (ret); 66 } 67 68 /* 69 * Try to cancel active hrtimer. 70 * Return 1 if timer was active and cancellation succeeded, 0 if timer was 71 * inactive, or -1 if the timer is being serviced and can't be cancelled. 72 */ 73 int 74 linux_hrtimer_try_to_cancel(struct hrtimer *hrtimer) 75 { 76 int ret; 77 78 mtx_lock(&hrtimer->mtx); 79 ret = callout_stop(&hrtimer->callout); 80 mtx_unlock(&hrtimer->mtx); 81 if (ret > 0) { 82 return (1); 83 } else if (ret < 0) { 84 return (0); 85 } else { 86 return (-1); 87 } 88 } 89 90 /* 91 * Cancel active hrtimer. 92 * Return 1 if timer was active and cancellation succeeded, or 0 otherwise. 93 */ 94 int 95 linux_hrtimer_cancel(struct hrtimer *hrtimer) 96 { 97 98 return (callout_drain(&hrtimer->callout) > 0); 99 } 100 101 void 102 linux_hrtimer_init(struct hrtimer *hrtimer) 103 { 104 105 memset(hrtimer, 0, sizeof(*hrtimer)); 106 mtx_init(&hrtimer->mtx, "hrtimer", NULL, 107 MTX_DEF | MTX_RECURSE | MTX_NOWITNESS); 108 callout_init_mtx(&hrtimer->callout, &hrtimer->mtx, 0); 109 } 110 111 void 112 linux_hrtimer_set_expires(struct hrtimer *hrtimer, ktime_t time) 113 { 114 hrtimer->expires = ktime_to_ns(time); 115 } 116 117 void 118 linux_hrtimer_start(struct hrtimer *hrtimer, ktime_t time) 119 { 120 121 linux_hrtimer_start_range_ns(hrtimer, time, 0); 122 } 123 124 void 125 linux_hrtimer_start_range_ns(struct hrtimer *hrtimer, ktime_t time, 126 int64_t nsec) 127 { 128 129 mtx_lock(&hrtimer->mtx); 130 hrtimer->precision = nsec; 131 callout_reset_sbt(&hrtimer->callout, nstosbt(ktime_to_ns(time)), 132 nstosbt(nsec), hrtimer_call_handler, hrtimer, 0); 133 mtx_unlock(&hrtimer->mtx); 134 } 135 136 void 137 linux_hrtimer_forward_now(struct hrtimer *hrtimer, ktime_t interval) 138 { 139 140 mtx_lock(&hrtimer->mtx); 141 callout_reset_sbt(&hrtimer->callout, nstosbt(ktime_to_ns(interval)), 142 nstosbt(hrtimer->precision), hrtimer_call_handler, hrtimer, 0); 143 mtx_unlock(&hrtimer->mtx); 144 } 145