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Re: nested interrupts
>
> As I was explained here, a main purpose of a DSR is to avoid
> scheduler's ready list manipulation from an interrupt. DSR mechanism
> serializes access to the scheduler (to suspend or resume a thread, or
> to send a message), thus completely avoiding disabling interrupts when
> posting. Quite neat. There is a price to pay, however, since DSR
> mechanism nearly doubles the time between posting interrupt and thread
> resumption. Bearing this in mind, the only thing DSR absolutely has to
> do is to notify the scheduler. All the rest ought to be done either in
> an ISR or in a thread.
>
> Regards,
> Sergei Slobodov
Thanks for your explanation. But as I knew, ISRs should be as short as
possible to reduce the time of masking interrupts and other non-critical
stuff can be processed in DSRs. So I don't understand what the following
means:
"Bearing this in mind, the only thing DSR absolutely has to do is to
notify the scheduler. All the rest ought to be done either in an ISR or
in a thread."