hi;
i am trying to write a kernel for 8051/80552 controller.i want to know answers
to following questions.
1.consider following case.task a with higher priority is running.other lower priority task b is blocked.it receives a message and becomes rtr.but scheduler keeps a active because of high.prio.now b receives another
event say an interrupt.still a is running due to higher prio.after a blocks on certain conditon b starts running.now how are the unblocking events to be processed?i can use
fifo logic to inform programmer about the unblocking event.here the time sequence shall be obeyed.
the other choice is i give a complete snapshot of types of events pending viz.interrupt and message.then programmer can decide the order of processing.

what is preferred?

2.task can often be blocked for an event upto a certain time.i am referring to timeout setting.if multiple tasks are setting timeout periods then on every timeout interrupt some extensive calculaton as regards to individual timing has to be done.is there a limit on how many tasks max.can ask for timeout?because if a large no.of them ask for timeout it might take a lot of time.

is there any standard data structure/algorithm for it?

thanks
pranav phatak