1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
9 #include <sys/timerfd.h>
11 #include <rte_interrupts.h>
12 #include <rte_alarm.h>
13 #include <rte_common.h>
14 #include <rte_errno.h>
15 #include <rte_spinlock.h>
16 #include <rte_eal_trace.h>
18 #include <eal_private.h>
22 #define TFD_NONBLOCK O_NONBLOCK
25 #define NS_PER_US 1000
26 #define US_PER_MS 1000
29 #define US_PER_S (US_PER_MS * MS_PER_S)
32 #ifdef CLOCK_MONOTONIC_RAW /* Defined in glibc bits/time.h */
33 #define CLOCK_TYPE_ID CLOCK_MONOTONIC_RAW
35 #define CLOCK_TYPE_ID CLOCK_MONOTONIC
39 LIST_ENTRY(alarm_entry) next;
41 rte_eal_alarm_callback cb_fn;
43 volatile uint8_t executing;
44 volatile pthread_t executing_id;
47 static LIST_HEAD(alarm_list, alarm_entry) alarm_list = LIST_HEAD_INITIALIZER();
48 static rte_spinlock_t alarm_list_lk = RTE_SPINLOCK_INITIALIZER;
50 static struct rte_intr_handle *intr_handle;
51 static int handler_registered = 0;
52 static void eal_alarm_callback(void *arg);
55 rte_eal_alarm_cleanup(void)
57 rte_intr_instance_free(intr_handle);
61 rte_eal_alarm_init(void)
64 intr_handle = rte_intr_instance_alloc(RTE_INTR_INSTANCE_F_PRIVATE);
65 if (intr_handle == NULL) {
66 RTE_LOG(ERR, EAL, "Fail to allocate intr_handle\n");
70 if (rte_intr_type_set(intr_handle, RTE_INTR_HANDLE_ALARM))
73 /* create a timerfd file descriptor */
74 if (rte_intr_fd_set(intr_handle,
75 timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK)))
78 if (rte_intr_fd_get(intr_handle) == -1)
83 rte_intr_instance_free(intr_handle);
89 eal_alarm_callback(void *arg __rte_unused)
92 struct alarm_entry *ap;
94 rte_spinlock_lock(&alarm_list_lk);
95 while ((ap = LIST_FIRST(&alarm_list)) !=NULL &&
96 clock_gettime(CLOCK_TYPE_ID, &now) == 0 &&
97 (ap->time.tv_sec < now.tv_sec || (ap->time.tv_sec == now.tv_sec &&
98 (ap->time.tv_usec * NS_PER_US) <= now.tv_nsec))) {
100 ap->executing_id = pthread_self();
101 rte_spinlock_unlock(&alarm_list_lk);
103 ap->cb_fn(ap->cb_arg);
105 rte_spinlock_lock(&alarm_list_lk);
107 LIST_REMOVE(ap, next);
111 if (!LIST_EMPTY(&alarm_list)) {
112 struct itimerspec atime = { .it_interval = { 0, 0 } };
114 ap = LIST_FIRST(&alarm_list);
115 atime.it_value.tv_sec = ap->time.tv_sec;
116 atime.it_value.tv_nsec = ap->time.tv_usec * NS_PER_US;
117 /* perform borrow for subtraction if necessary */
118 if (now.tv_nsec > (ap->time.tv_usec * NS_PER_US))
119 atime.it_value.tv_sec--, atime.it_value.tv_nsec += US_PER_S * NS_PER_US;
121 atime.it_value.tv_sec -= now.tv_sec;
122 atime.it_value.tv_nsec -= now.tv_nsec;
123 timerfd_settime(rte_intr_fd_get(intr_handle), 0, &atime, NULL);
125 rte_spinlock_unlock(&alarm_list_lk);
129 rte_eal_alarm_set(uint64_t us, rte_eal_alarm_callback cb_fn, void *cb_arg)
133 struct alarm_entry *ap, *new_alarm;
135 /* Check parameters, including that us won't cause a uint64_t overflow */
136 if (us < 1 || us > (UINT64_MAX - US_PER_S) || cb_fn == NULL)
139 new_alarm = calloc(1, sizeof(*new_alarm));
140 if (new_alarm == NULL)
143 /* use current time to calculate absolute time of alarm */
144 clock_gettime(CLOCK_TYPE_ID, &now);
146 new_alarm->cb_fn = cb_fn;
147 new_alarm->cb_arg = cb_arg;
148 new_alarm->time.tv_usec = ((now.tv_nsec / NS_PER_US) + us) % US_PER_S;
149 new_alarm->time.tv_sec = now.tv_sec + (((now.tv_nsec / NS_PER_US) + us) / US_PER_S);
151 rte_spinlock_lock(&alarm_list_lk);
152 if (!handler_registered) {
153 /* registration can fail, callback can be registered later */
154 if (rte_intr_callback_register(intr_handle,
155 eal_alarm_callback, NULL) == 0)
156 handler_registered = 1;
159 if (LIST_EMPTY(&alarm_list))
160 LIST_INSERT_HEAD(&alarm_list, new_alarm, next);
162 LIST_FOREACH(ap, &alarm_list, next) {
163 if (ap->time.tv_sec > new_alarm->time.tv_sec ||
164 (ap->time.tv_sec == new_alarm->time.tv_sec &&
165 ap->time.tv_usec > new_alarm->time.tv_usec)){
166 LIST_INSERT_BEFORE(ap, new_alarm, next);
169 if (LIST_NEXT(ap, next) == NULL) {
170 LIST_INSERT_AFTER(ap, new_alarm, next);
176 if (LIST_FIRST(&alarm_list) == new_alarm) {
177 struct itimerspec alarm_time = {
178 .it_interval = {0, 0},
180 .tv_sec = us / US_PER_S,
181 .tv_nsec = (us % US_PER_S) * NS_PER_US,
184 ret |= timerfd_settime(rte_intr_fd_get(intr_handle), 0, &alarm_time, NULL);
186 rte_spinlock_unlock(&alarm_list_lk);
188 rte_eal_trace_alarm_set(us, cb_fn, cb_arg, ret);
193 rte_eal_alarm_cancel(rte_eal_alarm_callback cb_fn, void *cb_arg)
195 struct alarm_entry *ap, *ap_prev;
207 rte_spinlock_lock(&alarm_list_lk);
208 /* remove any matches at the start of the list */
209 while ((ap = LIST_FIRST(&alarm_list)) != NULL &&
210 cb_fn == ap->cb_fn &&
211 (cb_arg == (void *)-1 || cb_arg == ap->cb_arg)) {
213 if (ap->executing == 0) {
214 LIST_REMOVE(ap, next);
218 /* If calling from other context, mark that alarm is executing
219 * so loop can spin till it finish. Otherwise we are trying to
220 * cancel our self - mark it by EINPROGRESS */
221 if (pthread_equal(ap->executing_id, pthread_self()) == 0)
231 /* now go through list, removing entries not at start */
232 LIST_FOREACH(ap, &alarm_list, next) {
233 /* this won't be true first time through */
234 if (cb_fn == ap->cb_fn &&
235 (cb_arg == (void *)-1 || cb_arg == ap->cb_arg)) {
237 if (ap->executing == 0) {
238 LIST_REMOVE(ap, next);
242 } else if (pthread_equal(ap->executing_id, pthread_self()) == 0)
249 rte_spinlock_unlock(&alarm_list_lk);
250 } while (executing != 0);
252 if (count == 0 && err == 0)
257 rte_eal_trace_alarm_cancel(cb_fn, cb_arg, count);