Re: [PATCH 1/3] perf, pt, coresight: Clean up address filter structure

From: Will Deacon
Date: Thu Jan 18 2018 - 12:06:33 EST


On Thu, Jan 18, 2018 at 09:59:26AM -0700, Mathieu Poirier wrote:
> On 17 January 2018 at 05:31, Alexander Shishkin
> <alexander.shishkin@xxxxxxxxxxxxxxx> wrote:
> > On Tue, Feb 07, 2017 at 10:50:50AM -0700, Mathieu Poirier wrote:
> >> > index 39106ae61b..d7a11faac1 100644
> >> > --- a/kernel/events/core.c
> >> > +++ b/kernel/events/core.c
> >> > @@ -8194,7 +8194,8 @@ static void perf_event_addr_filters_apply(struct perf_event *event)
> >> > * * for kernel addresses: <start address>[/<size>]
> >> > * * for object files: <start address>[/<size>]@</path/to/object/file>
> >> > *
> >> > - * if <size> is not specified, the range is treated as a single address.
> >> > + * if <size> is not specified or is zero, the range is treated as a single
> >> > + * address; not valid for ACTION=="filter".
> >>
> >> Now that a size of 0 can't be specified with a "filter" action, I'm
> >> good with that statement.
> >
> > Hi Mathieu, I completely lost track of this.
> >
> > Following is the commit I found dangilng in one of my local branches.
> > Does this make sense to you? Thanks!
>
> Oh boy! That's a whole year ago... Give me some time to wrap my
> brain around it again.

Do we need anything for SPE, or is this only applicable to certain types of
tracing PMUs?

Will