1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
11 #include <sys/timerfd.h>
13 #include <rte_memory.h>
14 #include <rte_interrupts.h>
15 #include <rte_alarm.h>
16 #include <rte_common.h>
17 #include <rte_per_lcore.h>
19 #include <rte_launch.h>
20 #include <rte_lcore.h>
21 #include <rte_errno.h>
22 #include <rte_spinlock.h>
23 #include <eal_private.h>
27 #define TFD_NONBLOCK O_NONBLOCK
30 #define NS_PER_US 1000
31 #define US_PER_MS 1000
34 #define US_PER_S (US_PER_MS * MS_PER_S)
37 #ifdef CLOCK_MONOTONIC_RAW /* Defined in glibc bits/time.h */
38 #define CLOCK_TYPE_ID CLOCK_MONOTONIC_RAW
40 #define CLOCK_TYPE_ID CLOCK_MONOTONIC
44 LIST_ENTRY(alarm_entry) next;
46 rte_eal_alarm_callback cb_fn;
48 volatile uint8_t executing;
49 volatile pthread_t executing_id;
52 static LIST_HEAD(alarm_list, alarm_entry) alarm_list = LIST_HEAD_INITIALIZER();
53 static rte_spinlock_t alarm_list_lk = RTE_SPINLOCK_INITIALIZER;
55 static struct rte_intr_handle intr_handle = {.fd = -1 };
56 static int handler_registered = 0;
57 static void eal_alarm_callback(void *arg);
60 rte_eal_alarm_init(void)
62 intr_handle.type = RTE_INTR_HANDLE_ALARM;
63 /* create a timerfd file descriptor */
64 intr_handle.fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK);
65 if (intr_handle.fd == -1)
76 eal_alarm_callback(void *arg __rte_unused)
79 struct alarm_entry *ap;
81 rte_spinlock_lock(&alarm_list_lk);
82 while ((ap = LIST_FIRST(&alarm_list)) !=NULL &&
83 clock_gettime(CLOCK_TYPE_ID, &now) == 0 &&
84 (ap->time.tv_sec < now.tv_sec || (ap->time.tv_sec == now.tv_sec &&
85 (ap->time.tv_usec * NS_PER_US) <= now.tv_nsec))) {
87 ap->executing_id = pthread_self();
88 rte_spinlock_unlock(&alarm_list_lk);
90 ap->cb_fn(ap->cb_arg);
92 rte_spinlock_lock(&alarm_list_lk);
94 LIST_REMOVE(ap, next);
98 if (!LIST_EMPTY(&alarm_list)) {
99 struct itimerspec atime = { .it_interval = { 0, 0 } };
101 ap = LIST_FIRST(&alarm_list);
102 atime.it_value.tv_sec = ap->time.tv_sec;
103 atime.it_value.tv_nsec = ap->time.tv_usec * NS_PER_US;
104 /* perform borrow for subtraction if necessary */
105 if (now.tv_nsec > (ap->time.tv_usec * NS_PER_US))
106 atime.it_value.tv_sec--, atime.it_value.tv_nsec += US_PER_S * NS_PER_US;
108 atime.it_value.tv_sec -= now.tv_sec;
109 atime.it_value.tv_nsec -= now.tv_nsec;
110 timerfd_settime(intr_handle.fd, 0, &atime, NULL);
112 rte_spinlock_unlock(&alarm_list_lk);
116 rte_eal_alarm_set(uint64_t us, rte_eal_alarm_callback cb_fn, void *cb_arg)
120 struct alarm_entry *ap, *new_alarm;
122 /* Check parameters, including that us won't cause a uint64_t overflow */
123 if (us < 1 || us > (UINT64_MAX - US_PER_S) || cb_fn == NULL)
126 new_alarm = calloc(1, sizeof(*new_alarm));
127 if (new_alarm == NULL)
130 /* use current time to calculate absolute time of alarm */
131 clock_gettime(CLOCK_TYPE_ID, &now);
133 new_alarm->cb_fn = cb_fn;
134 new_alarm->cb_arg = cb_arg;
135 new_alarm->time.tv_usec = ((now.tv_nsec / NS_PER_US) + us) % US_PER_S;
136 new_alarm->time.tv_sec = now.tv_sec + (((now.tv_nsec / NS_PER_US) + us) / US_PER_S);
138 rte_spinlock_lock(&alarm_list_lk);
139 if (!handler_registered) {
140 /* registration can fail, callback can be registered later */
141 if (rte_intr_callback_register(&intr_handle,
142 eal_alarm_callback, NULL) == 0)
143 handler_registered = 1;
146 if (LIST_EMPTY(&alarm_list))
147 LIST_INSERT_HEAD(&alarm_list, new_alarm, next);
149 LIST_FOREACH(ap, &alarm_list, next) {
150 if (ap->time.tv_sec > new_alarm->time.tv_sec ||
151 (ap->time.tv_sec == new_alarm->time.tv_sec &&
152 ap->time.tv_usec > new_alarm->time.tv_usec)){
153 LIST_INSERT_BEFORE(ap, new_alarm, next);
156 if (LIST_NEXT(ap, next) == NULL) {
157 LIST_INSERT_AFTER(ap, new_alarm, next);
163 if (LIST_FIRST(&alarm_list) == new_alarm) {
164 struct itimerspec alarm_time = {
165 .it_interval = {0, 0},
167 .tv_sec = us / US_PER_S,
168 .tv_nsec = (us % US_PER_S) * NS_PER_US,
171 ret |= timerfd_settime(intr_handle.fd, 0, &alarm_time, NULL);
173 rte_spinlock_unlock(&alarm_list_lk);
179 rte_eal_alarm_cancel(rte_eal_alarm_callback cb_fn, void *cb_arg)
181 struct alarm_entry *ap, *ap_prev;
193 rte_spinlock_lock(&alarm_list_lk);
194 /* remove any matches at the start of the list */
195 while ((ap = LIST_FIRST(&alarm_list)) != NULL &&
196 cb_fn == ap->cb_fn &&
197 (cb_arg == (void *)-1 || cb_arg == ap->cb_arg)) {
199 if (ap->executing == 0) {
200 LIST_REMOVE(ap, next);
204 /* If calling from other context, mark that alarm is executing
205 * so loop can spin till it finish. Otherwise we are trying to
206 * cancel our self - mark it by EINPROGRESS */
207 if (pthread_equal(ap->executing_id, pthread_self()) == 0)
217 /* now go through list, removing entries not at start */
218 LIST_FOREACH(ap, &alarm_list, next) {
219 /* this won't be true first time through */
220 if (cb_fn == ap->cb_fn &&
221 (cb_arg == (void *)-1 || cb_arg == ap->cb_arg)) {
223 if (ap->executing == 0) {
224 LIST_REMOVE(ap, next);
228 } else if (pthread_equal(ap->executing_id, pthread_self()) == 0)
235 rte_spinlock_unlock(&alarm_list_lk);
236 } while (executing != 0);
238 if (count == 0 && err == 0)