Re: [PATCH v4 2/2] soc: qcom: add l2 cache perf events driver
From: Mark Rutland
Date: Fri Sep 02 2016 - 06:06:42 EST
On Thu, Sep 01, 2016 at 05:30:52PM +0100, Mark Rutland wrote:
> On Tue, Aug 30, 2016 at 01:01:33PM -0400, Neil Leeder wrote:
> > +static DEFINE_MUTEX(l2cache_pmu_mutex);
>
> A mutex (which can sleep) is not safe for the hotplug state machine
> stuff. See recent patches to the arm_pmu code.
>
> That's further subsumed by the multi-instance stuff, so this (and the
> list) will not be necessary shortly.
This has *just* landed in tip. See the smp/hotplug branch [1]. The
arm_pmu change [2] should serve as an example of what to do.
Thanks,
Mark.
[1] https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/log/?h=smp/hotplug
[2] https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?h=smp/hotplug&id=cc727977acb0fe05b7aa1f00cccb893530820895