Re: [9fans] Quick question on stopping a process that waits for IO

["Roman V. Shaposhnik" <rvs@sun.com>]

erik quanstrom wrote:
>> How? If there's a stop message already written to /proc/n/ctl. Once
>> that is done, the process is guaranteed to be in 2 states and those
>> states only: continue waiting for the I/O, being actually Stopped.
>> Both of the don't let the scheduler take it to the runqueue.
>>
>
> here's the senerio, i think  (works fine on a single processor)
> a			b
> acquire debug lock
> sleep			complete io
> 			sched
> 			run a bit
> 			syscall
> wakeup
But how "run a bit" could possibly happen if after the "stop" message
being sent right after the "complete io" the "b" process goes into
a "Stopped" state?

Thanks,
Roman.