RE: Bug 71331 - mlock yields processor to lower priority process

[Mike Galbraith]

On Fri, 2014-03-21 at 12:18 +0000, jimmie.davis@xxxxxxxxxx wrote:

> As the submitter of the bug, let me give you my perspective.
> SCHED_FIFO means run my task until it blocks or a higher priority task
> pre-empts it.  Period.

It blocked.
> 
> mlock() doesn't block. check the man page.
> 
I don't see that specified.

(or how it could be, but what do I know, IANIPL)

> Any other way and you are not able to use priority based scheduling. 

Sure you can, allocate and lock down resources before entering critical
sections.

If you think donning a SCHED_FIFO super-suit should make your task
unstoppable, you're gonna be very disappointed.  Fact is if your
Juggernaut bumps ever so gently into a contended sleeping variety lock
(and in the rt kernel that means nearly every lock), it will block.

-Mike

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