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Date: Tue, 18 Mar 2003 19:04:07 -0800
From: Andrew Morton <akpm@digeo.com>
To: george anzinger <george@mvista.com>
Cc: async@cc.gatech.edu, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] limits on SCHED_FIFO tasks
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george anzinger <george@mvista.com> wrote:
>
> If the issue is regaining control after some RT task goes into a loop, 
> the way this is usually done is to keep a session around with a higher 
> priority.  Using this concept, one might provide tools that, from 
> userland, insure that such a session exists prior to launching the 
> "suspect" code.  I fail to see the need for this sort of code in the 
> kernel.

That works, until your shell calls ext3_mark_inode_dirty(), which blocks on
kjournald activity.  kjournald is SCHED_OTHER, and never runs...