Messages in this thread | | | Date | Mon, 11 May 2015 15:25:12 -0400 | From | Chris Metcalf <> | Subject | Re: [PATCH 0/6] support "dataplane" mode for nohz_full |
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On 05/11/2015 03:19 PM, Mike Galbraith wrote: > I really shouldn't have acked nohz_full -> isolcpus. Beside the fact > that old static isolcpus was_supposed_ to crawl off and die, I know > beyond doubt that having isolated a cpu as well as you can definitely > does NOT imply that said cpu should become tickless.
True, at a high level, I agree that it would be better to have a top-level concept like Frederic's proposed ISOLATION that includes isolcpus and nohz_cpu (and other stuff as needed).
That said, what you wrote above is wrong; even with the patch you acked, setting isolcpus does not automatically turn on nohz_full for a given cpu. The patch made it true the other way around: when you say nohz_full, you automatically get isolcpus on that cpu too. That does, at least, make sense for the semantics of nohz_full.
-- Chris Metcalf, EZChip Semiconductor http://www.ezchip.com
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