Re: preempt_disable and sleep()

From: Sven-Thorsten Dietrich
Date: Thu May 13 2010 - 14:43:43 EST


On Fri, 2010-05-14 at 00:02 +0530, ratheesh k wrote:
> I am running RT linux .
>
> /* code snippet */
>
> preempt_disable()
> ...........
> sleep(10);
> '............
> preempt_enable()
>
>
> will this sleep() will cause reschedule ?.
>

Why would you do this?

If you had tried this code, you would have seen the corresponding stack
dump on the console.

> if an interrupt comes while premption is disabled , how it is handled ?.
>

Depends on the number of (idle) cores, the setting of CONFIG_PREEMPT_[]
and the type of interrupt.

RT threaded IRQs would not run until preemption is enabled on a single
core system.



> Thanks,
> Ratheesh
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