Re: [PATCH 4/7] perf: be less pessimistic when scheduling events

From: Peter Zijlstra
Date: Mon Feb 10 2014 - 12:59:07 EST


On Mon, Feb 10, 2014 at 05:44:21PM +0000, Mark Rutland wrote:
> This patch makes ctx_flexible_sched_in attempt to schedule every group
> in the flexible_groups list even when earlier groups failed to schedule,
> enabling more groups to be scheduled simultaneously.

Since you're basically free to create as many events as you want, you can
(as an unprivilidged user) make the context switch to and from your task
arbitrarily expensive.

So no, that's not going to fly.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/