Re: [patch V2 24/24] cpu/hotplug: Convert hotplug locking to percpu rwsem

From: Steven Rostedt
Date: Wed May 10 2017 - 13:15:46 EST


On Wed, 10 May 2017 12:30:57 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:


> I finally got some time to look at this. I'm looking at your commit:
>
> commit b53e5129c4c7ab47ec4f709fd8f5784ca45fb46d
> Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Date: Sun Apr 23 12:17:13 2017 +0200
>
> trace/perf: Cure hotplug lock ordering issues
>
> What were the circular locking dependencies that were uncovered.
>
> event_mutex could possibly be broken up, if that helps. It sorta became
> a catch all for various modifications to tracing.
>

I checked out the commit before this and started playing with it. I see
some of the issues now. I'll look more into it.

-- Steve