To clear event(s) of another thread

[xiaomin]

chibi RT provides API to clear event in current task with chEvtGetAndClearEvents(eventmask_t). Now what I need is to clear event(s) of another thread. Suppose I know the thread reference, it seems I can just lock and directly manipulate thd->epending &= ~event. But is it safe? Shall I check thread priority? Shall I check whether the other thread is already in ready to run list? Is there any other protection I should add?

[Giovanni]

Hi,

It would be safe if done in a critical zone, so use chSysLock/Unlock.

Giovanni

[faisal]

Hi,

It would be safe if done in a critical zone, so use chSysLock/Unlock.

Giovanni

Wouldn't one also need to preform a reschedule before exiting the critical zone?

[Giovanni]

Clearing events would not wake up a thread so rescheduling is not required. It only has to be performed after that the state of the ready list has changed, usually after calling chSchReadyI().

Giovanni