[PATCH v3 2/2] coresight: core: Disable helpers for devices that fail to enable

[Mike Leach]

On Tue, 15 Apr 2025 at 14:51, James Clark <james.clark at linaro.org> wrote:
>
>
>
> On 08/04/2025 8:59 pm, Yabin Cui wrote:
> > When enabling a SINK or LINK type coresight device fails, the
> > associated helpers should be disabled.
> >
> > Signed-off-by: Yabin Cui <yabinc at google.com>
> > Suggested-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> > ---
> >   drivers/hwtracing/coresight/coresight-core.c | 9 +++++++--
> >   1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> > index fb43ef6a3b1f..a56ba9087538 100644
> > --- a/drivers/hwtracing/coresight/coresight-core.c
> > +++ b/drivers/hwtracing/coresight/coresight-core.c
> > @@ -486,8 +486,10 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode,
> >                        * that need disabling. Disabling the path here
> >                        * would mean we could disrupt an existing session.
> >                        */
> > -                     if (ret)
> > +                     if (ret) {
> > +                             coresight_disable_helpers(csdev);
>
> Hi Yabin,
>
> Unfortunately coresight_disable_helpers() takes a path pointer now so
> this needs to be updated.
>
> I tested with that change made and it works ok.
>
> >                               goto out;
> > +                     }
> >                       break;
> >               case CORESIGHT_DEV_TYPE_SOURCE:
> >                       /* sources are enabled from either sysFS or Perf */
> > @@ -496,10 +498,13 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode,
> >                       parent = list_prev_entry(nd, link)->csdev;
> >                       child = list_next_entry(nd, link)->csdev;
> >                       ret = coresight_enable_link(csdev, parent, child, source);
> > -                     if (ret)
> > +                     if (ret) {
> > +                             coresight_disable_helpers(csdev);
> >                               goto err;
> > +                     }
> >                       break;
> >               default:
> > +                     coresight_disable_helpers(csdev);
>
> Minor nit, you could collapse these last two into "goto
> err_disable_helpers" and add another label before err: that disables
> helpers before falling through to err:.
>
> Other than that:
>
> Reviewed-by: James Clark <james.clark at linaro.org>
>
> >                       goto err;
> >               }
> >       }
>

Subject to James' comments -

Reviewed-by: Mike Leach <mike.leach at linaro.org>


-- 
Mike Leach
Principal Engineer, ARM Ltd.
Manchester Design Centre. UK