fix minor bug in add_repeating_timer_us, and add some comments (#621)

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Graham Sanderson 2021-10-25 09:32:02 -05:00 committed by GitHub
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commit 05418b4e71
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2 changed files with 46 additions and 14 deletions

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@ -416,9 +416,12 @@ void alarm_pool_destroy(alarm_pool_t *pool);
* @param time the timestamp when (after which) the callback should fire * @param time the timestamp when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls before or during this call before the alarm can be set,
* @return >0 the alarm id * then the callback should be called during (by) this function instead
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return >0 the alarm id for an active (at the time of return) alarm
* @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past); alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past);
@ -438,9 +441,12 @@ alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, ala
* @param us the delay (from now) in microseconds when (after which) the callback should fire * @param us the delay (from now) in microseconds when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls during this call before the alarm can be set,
* then the callback should be called during (by) this function instead
* @return >0 the alarm id * @return >0 the alarm id
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
static inline alarm_id_t alarm_pool_add_alarm_in_us(alarm_pool_t *pool, uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) { static inline alarm_id_t alarm_pool_add_alarm_in_us(alarm_pool_t *pool, uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) {
@ -462,9 +468,12 @@ static inline alarm_id_t alarm_pool_add_alarm_in_us(alarm_pool_t *pool, uint64_t
* @param ms the delay (from now) in milliseconds when (after which) the callback should fire * @param ms the delay (from now) in milliseconds when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls before or during this call before the alarm can be set,
* then the callback should be called during (by) this function instead
* @return >0 the alarm id * @return >0 the alarm id
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
static inline alarm_id_t alarm_pool_add_alarm_in_ms(alarm_pool_t *pool, uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) { static inline alarm_id_t alarm_pool_add_alarm_in_ms(alarm_pool_t *pool, uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) {
@ -496,9 +505,12 @@ bool alarm_pool_cancel_alarm(alarm_pool_t *pool, alarm_id_t alarm_id);
* @param time the timestamp when (after which) the callback should fire * @param time the timestamp when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls before or during this call before the alarm can be set,
* then the callback should be called during (by) this function instead
* @return >0 the alarm id * @return >0 the alarm id
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
static inline alarm_id_t add_alarm_at(absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past) { static inline alarm_id_t add_alarm_at(absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past) {
@ -519,9 +531,12 @@ static inline alarm_id_t add_alarm_at(absolute_time_t time, alarm_callback_t cal
* @param us the delay (from now) in microseconds when (after which) the callback should fire * @param us the delay (from now) in microseconds when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls during this call before the alarm can be set,
* then the callback should be called during (by) this function instead
* @return >0 the alarm id * @return >0 the alarm id
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
static inline alarm_id_t add_alarm_in_us(uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) { static inline alarm_id_t add_alarm_in_us(uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) {
@ -542,9 +557,12 @@ static inline alarm_id_t add_alarm_in_us(uint64_t us, alarm_callback_t callback,
* @param ms the delay (from now) in milliseconds when (after which) the callback should fire * @param ms the delay (from now) in milliseconds when (after which) the callback should fire
* @param callback the callback function * @param callback the callback function
* @param user_data user data to pass to the callback function * @param user_data user data to pass to the callback function
* @param fire_if_past if true, this method will call the callback itself before returning 0 if the timestamp happens before or during this method call * @param fire_if_past if true, and the alarm time falls during this call before the alarm can be set,
* then the callback should be called during (by) this function instead
* @return >0 the alarm id * @return >0 the alarm id
* @return 0 the target timestamp was during or before this method call (whether the callback was called depends on fire_if_past) * @return 0 if the alarm time passed before or during the call AND there is no active alarm to return the id of.
* The latter can either happen because fire_if_past was false (i.e. no timer was ever created),
* or if the callback <i>was</i> called during this method but the callback cancelled itself by returning 0
* @return -1 if there were no alarm slots available * @return -1 if there were no alarm slots available
*/ */
static inline alarm_id_t add_alarm_in_ms(uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) { static inline alarm_id_t add_alarm_in_ms(uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) {

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@ -219,18 +219,26 @@ alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, ala
do { do {
uint8_t id_high = 0; uint8_t id_high = 0;
uint32_t save = spin_lock_blocking(pool->lock); uint32_t save = spin_lock_blocking(pool->lock);
pheap_node_id_t id = add_alarm_under_lock(pool, time, callback, user_data, 0, false, &missed); pheap_node_id_t id = add_alarm_under_lock(pool, time, callback, user_data, 0, false, &missed);
if (id) id_high = *get_entry_id_high(pool, id); if (id) id_high = *get_entry_id_high(pool, id);
spin_unlock(pool->lock, save); spin_unlock(pool->lock, save);
if (!id) { if (!id) {
// no space in pheap to allocate an alarm
return -1; return -1;
} }
// note that if missed was true, then the id was never added to the pheap (because we
// passed false for create_if_past arg above)
public_id = missed ? 0 : make_public_id(id_high, id); public_id = missed ? 0 : make_public_id(id_high, id);
if (missed && fire_if_past) { if (missed && fire_if_past) {
// ... so if fire_if_past == true we call the callback
int64_t repeat = callback(public_id, user_data); int64_t repeat = callback(public_id, user_data);
// if not repeated we have no id to return so set public_id to 0,
// otherwise we need to repeat, but will assign a new id next time
// todo arguably this does mean that the id passed to the first callback may differ from subsequent calls
if (!repeat) { if (!repeat) {
public_id = 0; public_id = 0;
break; break;
@ -240,6 +248,10 @@ alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, ala
time = delayed_by_us(get_absolute_time(), (uint64_t)repeat); time = delayed_by_us(get_absolute_time(), (uint64_t)repeat);
} }
} else { } else {
// either:
// a) missed == false && public_id is > 0
// b) missed == true && fire_if_past == false && public_id = 0
// but we are done in either case
break; break;
} }
} while (true); } while (true);
@ -302,7 +314,9 @@ bool alarm_pool_add_repeating_timer_us(alarm_pool_t *pool, int64_t delay_us, rep
out->user_data = user_data; out->user_data = user_data;
out->alarm_id = alarm_pool_add_alarm_at(pool, make_timeout_time_us((uint64_t)(delay_us >= 0 ? delay_us : -delay_us)), out->alarm_id = alarm_pool_add_alarm_at(pool, make_timeout_time_us((uint64_t)(delay_us >= 0 ? delay_us : -delay_us)),
repeating_timer_callback, out, true); repeating_timer_callback, out, true);
return out->alarm_id > 0; // note that if out->alarm_id is 0, then the callback was called during the above call (fire_if_past == true)
// and then the callback removed itself.
return out->alarm_id >= 0;
} }
bool cancel_repeating_timer(repeating_timer_t *timer) { bool cancel_repeating_timer(repeating_timer_t *timer) {