Re: [PATCH] perf/core: Enable the bp only if the .disable field is 0.

Jiri Olsa
2017-11-27T09:25:40Z

On Sun, Nov 26, 2017 at 10:50:27PM -0800, Milind Chabbi wrote:
> On Sun, Nov 26, 2017 at 10:43 PM, Milind Chabbi <chabbi.milind@gmail.com> wrote:
> > Signed-off-by: Milind Chabbi <chabbi.milind@gmail.com>
> > ---
> > kernel/events/core.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/events/core.c b/kernel/events/core.c
> > index 35747a58ffb4..1b8eae85e9de 100644
> > --- a/kernel/events/core.c
> > +++ b/kernel/events/core.c
> > @@ -2659,7 +2659,8 @@ static int perf_event_modify_breakpoint(struct perf_event *bp,
> > return err;
> > }
> >
> > - _perf_event_enable(bp);
> > + if (!attr->disabled)
> > + _perf_event_enable(bp);
> > return 0;
> > }
> >
> > --
> > 2.14.1
> >
>
> Hi Jirka,
> Thanks for your changes for proper accounting of the bp.
> This additional change is needed so that we do not enable the bp if
> the user has not asked to enable it.
> I did the testing for ioctl and it continues to show the significant
> speedups that I had originally seen.

right, I'll merge this in and post

thanks,
jirka