Re: [RFC][PATCH v2] sched/rt: Use IPI to trigger RT task push migration instead of pulling

From: Steven Rostedt
Date: Thu Feb 26 2015 - 07:45:23 EST


On Thu, 26 Feb 2015 08:49:07 +0100
Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> Yes, notice that we don't start iterating at the beginning; this in on
> purpose. If we start iterating at the beginning, _every_ cpu will again
> pile up on the first one.
>
> By starting at the current cpu, each cpu will start iteration some place
> else and hopefully, with a big enough system, different CPUs end up on a
> different rto cpu.

Note, v3 doesn't start at the current CPU, it starts at the original
CPU again. As the start of every IPI comes from a different CPU, this
still keeps a restart from clobbering the same CPU.

-- Steve
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