Re: [PATCH V4] perf: event preserve and create across cpu hotplug

From: Mukesh Ojha
Date: Tue Jun 18 2019 - 09:45:35 EST



On 6/18/2019 5:53 PM, Peter Zijlstra wrote:
On Tue, Jun 18, 2019 at 02:24:51PM +0530, Mukesh Ojha wrote:
Perf framework doesn't allow preserving CPU events across
CPU hotplugs. The events are scheduled out as and when the
CPU walks offline. Moreover, the framework also doesn't
allow the clients to create events on an offline CPU. As
a result, the clients have to keep on monitoring the CPU
state until it comes back online.

Therefore,
That's not a therefore. There's a distinct lack of rationale here. Why
do you want this?

Thanks Peter for coming back on this.

Missed to send the coverletter,
https://lkml.org/lkml/2019/5/31/438
Will resend this with coverletter.

Btw, This patch

is based on suggestion given by you on this
https://lkml.org/lkml/2018/2/16/763


Thanks.
Mukesh


Thanks.
Mukesh