Re: [PATCH HACK RFC] cpu: Prevent late-arriving interrupts from disrupting offline
From: Dietmar Eggemann
Date: Tue Jun 04 2019 - 09:33:32 EST
On 6/4/19 9:45 AM, Paul E. McKenney wrote:
On Mon, Jun 03, 2019 at 03:39:18PM +0200, Dietmar Eggemann wrote:
On 6/3/19 1:44 PM, Mark Rutland wrote:
On Mon, Jun 03, 2019 at 10:38:48AM +0200, Peter Zijlstra wrote:
On Sat, Jun 01, 2019 at 06:12:53PM -0700, Paul E. McKenney wrote:
Scheduling-clock interrupts can arrive late in the CPU-offline process,
[...]
05981277a4de1ad6 ("arm64: Use common outgoing-CPU-notification code")
... but it looks like Paul's patch to do so [1] fell through the cracks;
I'm not aware of any reason that shouldn't have been taken.
[1] https://lore.kernel.org/lkml/1431467407-1223-8-git-send-email-paulmck@xxxxxxxxxxxxxxxxxx/
Paul, do you want to resend that?
Please do. We're carrying this patch out-of-tree for while now in
our EAS integration to get cpu hotplug tests passing on TC2 (arm).
Huh. It still applies. But I have no means of testing it.
We can do the testing part on our TC2 platform, i.e. we're testing it
with each of our EAS mainline integration right now.
https://developer.arm.com/tools-and-software/open-source-software/linux-kernel/energy-aware-scheduling/eas-mainline-development
http://linux-arm.org/git?p=linux-power.git;a=commit;h=8cd16f1dc2cd896a0b1e2010b4992b33fdc11fe0
And it looks like the reason I dropped it was that I didn't get any
response from the maintainer. I sent a message to this effect to
linux-arm-kernel@xxxxxxxxxxxxxxxxxxx and linux@xxxxxxxxxxxxxxxx on May
21, 2015.
So here it is again. ;-)
I have queued this locally. Left to myself, I add the two of you on its
Cc: list and run it through my normal process. But given the history,
I would still want either an ack from the maintainer or, better, for
the maintainer to take the patch.
Or is there a better way for us to proceed on this?
You could send this patch also to linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
and cc rmk to get his opinion on the patch.
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