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Date: Thu, 1 Sep 2016 12:06:31 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Gilad Ben Yossef <giladb@mellanox.com>,
        Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [PATCH v15 04/13] task_isolation: add initial support
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On Tue, Aug 30, 2016 at 11:32:16AM -0400, Chris Metcalf wrote:
> On 8/30/2016 3:58 AM, Peter Zijlstra wrote:

> >What !? I really don't get this, what are you waiting for? Why is
> >rescheduling making things better.
> 
> We need to wait for the last dyntick to fire before we can return to
> userspace.  There are plenty of options as to what we can do in the
> meanwhile.

Why not keep your _TIF_TASK_ISOLATION_FOO flag set and re-enter the
loop?

I really don't see how setting TIF_NEED_RESCHED is helping anything.