Re: [PATCH 0/2] perf/hw_breakpoint: Fix breakpoint overcommit issue

[Frederic Weisbecker]

On Mon, Jul 15, 2019 at 02:47:37PM +0200, Peter Zijlstra wrote:
> On Thu, Jul 11, 2019 at 12:53:05PM +0200, Peter Zijlstra wrote:
> > > I wish we could use event->ctx->task instead but on pmu::init() there
> > > is no ctx yet (we could pass the task in parameter though) 
> > 
> > Right, that should be fairly easy.
> > 
> > > and on event->destroy() it's TASK_TOMBSTONE and retrieving the task at
> > > that time would be non trivial.
> > 
> > Well, right, we can maybe make TOMBSTONE be the LSB instead of the whole
> > word, then we can recover the task pointer... *yuck* though.
> 
> Something like the attached, completely untested patches.
> 
> I didn't do the hw_breakpoint bit, because I got lost in that, but this
> basically provides what you asked for I think.
> 

Thanks they look good! I can take them and work on top if you like.