Hi everybody, I have a question related to implementation of tsk_lock() for Cortex-M3. The manual says that the function disables the timer interrupt and thus prevents the RTOS from switching. But disabling the interrupt and clearing a pending interrupt flag are sometimes completely different stories. If I call tsk_lock() and immediately after it call tsk_ulock() the other tasks should not suffer, other than experience a few usec delay. What we found is that if the timer interrupt is due to happen between the calls of tsk_lock and tsk_unlock, the interrupt will be lost regardless of how quickly you call tsk_unlock. Which to me is an error - the tsk_lock should only disable the interrupt but keep the pending flag if it comes while the ISR is disabled, so that the ISR is called after tsk_unlock. Otherwise tasks that are waiting on os_dly_wait will miss a sys clock. Which is what we see. Can anybody comment if this is how it was designed? Thanks.
The tsk_lock() and tsk_unlock() are never used in RTX for Cortex-M library. Both functions are there for compatibility reasons with ARM library.
Instead of tsk_lock/tsk_unlock you might consider using __svc functions. They are never interrupted by RTX kernel.