diff options
| -rw-r--r-- | os/rt/include/chvt.h | 92 | ||||
| -rw-r--r-- | os/rt/src/chvt.c | 44 |
2 files changed, 85 insertions, 51 deletions
diff --git a/os/rt/include/chvt.h b/os/rt/include/chvt.h index b2118df07..01dc38ac6 100644 --- a/os/rt/include/chvt.h +++ b/os/rt/include/chvt.h @@ -340,6 +340,26 @@ static inline bool chVTIsArmedI(virtual_timer_t *vtp) { }
/**
+ * @brief Returns @p true if the specified timer is armed.
+ * @pre The timer must have been initialized using @p chVTObjectInit()
+ * or @p chVTDoSetI().
+ *
+ * @param[in] vtp the @p virtual_timer_t structure pointer
+ * @return true if the timer is armed.
+ *
+ * @api
+ */
+static inline bool chVTIsArmed(virtual_timer_t *vtp) {
+ bool b;
+
+ chSysLock();
+ b = chVTIsArmedI(vtp);
+ chSysUnlock();
+
+ return b;
+}
+
+/**
* @brief Disables a Virtual Timer.
* @note The timer is first checked and disabled only if armed.
* @pre The timer must have been initialized using @p chVTObjectInit()
@@ -466,35 +486,43 @@ static inline void chVTDoTickI(void) { }
#else /* CH_CFG_ST_TIMEDELTA > 0 */
virtual_timer_t *vtp;
+ systime_t now, delta;
+
+ /* First timer to be processed.*/
+ vtp = ch.vtlist.vt_next;
+ now = chVTGetSystemTimeX();
/* The list is assumed to be non-empty because an tick interrupt just
occurred.*/
- chDbgAssert(&ch.vtlist != (virtual_timers_list_t *)ch.vtlist.vt_next,
+ chDbgAssert(&ch.vtlist != (virtual_timers_list_t *)vtp,
"timers list empty");
- /* First timer to be processed, its time is assumed to be between
- "vt_lasttime" and "now".*/
- vtp = ch.vtlist.vt_next;
-
+ /* The timer time is assumed to be between "vt_lasttime" and "now".*/
chDbgAssert(chVTIsTimeWithinX(ch.vtlist.vt_lasttime + vtp->vt_delta,
ch.vtlist.vt_lasttime,
- chVTGetSystemTimeX() + 1),
+ now + 1),
"out of time window");
- /* Timers processing loop.*/
- while (true) {
- systime_t now;
+ /* All timers within the time window are triggered and removed,
+ note that the loop is stopped by the timers header having
+ "ch.vtlist.vt_delta == (systime_t)-1" which is greater than
+ all deltas.*/
+ while (vtp->vt_delta <= now - ch.vtlist.vt_lasttime) {
vtfunc_t fn;
/* The "last time" becomes this timer's expiration time.*/
ch.vtlist.vt_lasttime += vtp->vt_delta;
- /* The timer is removed from the list and marked as non-armed.*/
vtp->vt_next->vt_prev = (virtual_timer_t *)&ch.vtlist;
ch.vtlist.vt_next = vtp->vt_next;
fn = vtp->vt_func;
vtp->vt_func = NULL;
+ /* if the list becomes empty then the timer is stopped.*/
+ if (ch.vtlist.vt_next == (virtual_timer_t *)&ch.vtlist) {
+ port_timer_stop_alarm();
+ }
+
/* Leaving the system critical zone in order to execute the callback
and in order to give a preemption chance to higher priority
interrupts.*/
@@ -507,37 +535,27 @@ static inline void chVTDoTickI(void) { of the list.*/
chSysLockFromISR();
- /* If the list is empty then ending the loop, the list has to be
- re-checked because new timers could have been added/removed from
- within the callback or other ISRs.*/
+ /* Next element in the list, the current time could have advanced so
+ recalculating the time window.*/
vtp = ch.vtlist.vt_next;
- if (&ch.vtlist == (virtual_timers_list_t *)vtp) {
- /* Timers list empty, stopping alarms.*/
- port_timer_stop_alarm();
- return;
- }
-
- /* Getting the current system time and calculating the time window since
- the last time has expired.*/
now = chVTGetSystemTimeX();
+ }
- /* The next element is outside the current time window, the loop
- is stopped here.*/
- if (vtp->vt_delta > now - ch.vtlist.vt_lasttime) {
- /* Updating the alarm to the next deadline, deadline that must not be
- closer in time than the minimum time delta.*/
- systime_t delta = ch.vtlist.vt_lasttime + vtp->vt_delta - now;
- if (delta < (systime_t)CH_CFG_ST_TIMEDELTA) {
- delta = (systime_t)CH_CFG_ST_TIMEDELTA;
- }
- port_timer_set_alarm(now + delta);
-
- chDbgAssert((chVTGetSystemTimeX() - ch.vtlist.vt_lasttime) < delta,
- "exceeding delta");
-
- return;
- }
+ /* if the list is empty, nothing else to do.*/
+ if (ch.vtlist.vt_next == (virtual_timer_t *)&ch.vtlist) {
+ return;
}
+
+ /* Recalculating the next alarm time.*/
+ delta = ch.vtlist.vt_lasttime + vtp->vt_delta - now;
+ if (delta < (systime_t)CH_CFG_ST_TIMEDELTA) {
+ delta = (systime_t)CH_CFG_ST_TIMEDELTA;
+ }
+ port_timer_set_alarm(now + delta);
+
+ chDbgAssert((chVTGetSystemTimeX() - ch.vtlist.vt_lasttime) <=
+ (now + delta - ch.vtlist.vt_lasttime),
+ "exceeding delta");
#endif /* CH_CFG_ST_TIMEDELTA > 0 */
}
diff --git a/os/rt/src/chvt.c b/os/rt/src/chvt.c index 1d7661cb9..58fce1f6d 100644 --- a/os/rt/src/chvt.c +++ b/os/rt/src/chvt.c @@ -101,40 +101,56 @@ void chVTDoSetI(virtual_timer_t *vtp, systime_t delay, vtp->vt_par = par;
vtp->vt_func = vtfunc;
- p = ch.vtlist.vt_next;
#if CH_CFG_ST_TIMEDELTA > 0
{
systime_t now = chVTGetSystemTimeX();
- /* If the requested delay is lower than the minimum safe delta then it
- is raised to the minimum safe value.*/
- if (delay < (systime_t)CH_CFG_ST_TIMEDELTA) {
- delay = (systime_t)CH_CFG_ST_TIMEDELTA;
- }
+ /* Special case where the timers list is empty.*/
+ if (&ch.vtlist == (virtual_timers_list_t *)ch.vtlist.vt_next) {
+ /* If the requested delay is lower than the minimum safe delta then it
+ is raised to the minimum safe value.*/
+ if (delay < (systime_t)CH_CFG_ST_TIMEDELTA) {
+ delay = (systime_t)CH_CFG_ST_TIMEDELTA;
+ }
- if (&ch.vtlist == (virtual_timers_list_t *)p) {
/* The delta list is empty, the current time becomes the new
- delta list base time.*/
+ delta list base time, the timer is inserted.*/
ch.vtlist.vt_lasttime = now;
+ ch.vtlist.vt_next = vtp;
+ ch.vtlist.vt_prev = vtp;
+ vtp->vt_next = (virtual_timer_t *)&ch.vtlist;
+ vtp->vt_prev = (virtual_timer_t *)&ch.vtlist;
+ vtp->vt_delta = delay;
+
+ /* Being the first element in the list the alarm timer is started.*/
port_timer_start_alarm(ch.vtlist.vt_lasttime + delay);
+
+ return;
}
- else {
+
+ /* Special case where the timer will be placed as first element in a
+ non-empty list, the alarm needs to be recalculated.*/
+ if ((now + delay) < (ch.vtlist.vt_lasttime + ch.vtlist.vt_next->vt_delta)) {
+ /* If the requested delay is lower than the minimum safe delta then it
+ is raised to the minimum safe value.*/
+ if (delay < (systime_t)CH_CFG_ST_TIMEDELTA) {
+ delay = (systime_t)CH_CFG_ST_TIMEDELTA;
+ }
+
/* Now the delay is calculated as delta from the last tick interrupt
time.*/
delay += now - ch.vtlist.vt_lasttime;
- /* If the specified delay is closer in time than the first element
- in the delta list then it becomes the next alarm event in time.*/
- if (delay < p->vt_delta) {
- port_timer_set_alarm(ch.vtlist.vt_lasttime + delay);
- }
+ /* New alarm deadline.*/
+ port_timer_set_alarm(ch.vtlist.vt_lasttime + delay);
}
}
#endif /* CH_CFG_ST_TIMEDELTA > 0 */
/* The delta list is scanned in order to find the correct position for
this timer. */
+ p = ch.vtlist.vt_next;
while (p->vt_delta < delay) {
delay -= p->vt_delta;
p = p->vt_next;
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