Hi Sakari,
On Wed, Jan 16, 2019 at 12:34:07AM +0200, Sakari Ailus wrote:
> On Wed, Jan 16, 2019 at 12:21:36AM +0200, Laurent Pinchart wrote:
> > On Fri, Nov 02, 2018 at 12:31:17AM +0100, Niklas Söderlund wrote:
> >> From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> >>
> >> Instead of iterating over graph entities during the walk, iterate the pads
> >> through which the entity was first reached. This is required in order to
> >> make the entity pipeline pad-based rather than entity based.
> >>
> >> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> >> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> >> ---
> >> Documentation/media/kapi/mc-core.rst | 7 ++-
> >> drivers/media/media-entity.c | 46 ++++++++++--------
> >> drivers/media/platform/exynos4-is/media-dev.c | 20 ++++----
> >> drivers/media/platform/omap3isp/ispvideo.c | 17 +++----
> >> drivers/media/platform/vsp1/vsp1_video.c | 12 ++---
> >> drivers/media/platform/xilinx/xilinx-dma.c | 12 ++---
> >> drivers/media/v4l2-core/v4l2-mc.c | 25 +++++-----
> >> .../staging/media/davinci_vpfe/vpfe_video.c | 47 ++++++++++---------
> >> drivers/staging/media/omap4iss/iss_video.c | 34 +++++++-------
> >> include/media/media-entity.h | 7 +--
> >> 10 files changed, 122 insertions(+), 105 deletions(-)
> >
> > [snip]
> >
> >> diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c
> >> index 51d2a571c06db6a3..5813639c63b56a2c 100644
> >> --- a/drivers/media/platform/exynos4-is/media-dev.c
> >> +++ b/drivers/media/platform/exynos4-is/media-dev.c
> >> @@ -1135,7 +1135,7 @@ static int __fimc_md_modify_pipeline(struct media_entity *entity, bool enable)
> >> static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
> >> struct media_graph *graph)
> >> {
> >> - struct media_entity *entity_err = entity;
> >> + struct media_pad *pad, *pad_err = entity->pads;
> >> int ret;
> >>
> >> /*
> >> @@ -1144,13 +1144,13 @@ static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
> >> * through active links. This is needed as we cannot power on/off the
> >> * subdevs in random order.
> >> */
> >> - media_graph_walk_start(graph, entity->pads);
> >> + media_graph_walk_start(graph, pad_err);
> >
> > I would keep entity->pads here as we're not dealing with an error path.
> >
> >>
> >> - while ((entity = media_graph_walk_next(graph))) {
> >> - if (!is_media_entity_v4l2_video_device(entity))
> >> + while ((pad = media_graph_walk_next(graph))) {
> >> + if (!is_media_entity_v4l2_video_device(pad->entity))
> >> continue;
> >>
> >> - ret = __fimc_md_modify_pipeline(entity, enable);
> >> + ret = __fimc_md_modify_pipeline(pad->entity, enable);
> >>
> >> if (ret < 0)
> >> goto err;
> >> @@ -1159,15 +1159,15 @@ static int __fimc_md_modify_pipelines(struct media_entity *entity, bool enable,
> >> return 0;
> >>
> >> err:
> >> - media_graph_walk_start(graph, entity_err->pads);
> >> + media_graph_walk_start(graph, pad_err);
> >>
> >> - while ((entity_err = media_graph_walk_next(graph))) {
> >> - if (!is_media_entity_v4l2_video_device(entity_err))
> >> + while ((pad_err = media_graph_walk_next(graph))) {
> >> + if (!is_media_entity_v4l2_video_device(pad_err->entity))
> >> continue;
> >>
> >> - __fimc_md_modify_pipeline(entity_err, !enable);
> >> + __fimc_md_modify_pipeline(pad_err->entity, !enable);
> >>
> >> - if (entity_err == entity)
> >> + if (pad_err == pad)
> >> break;
> >> }
> >>
> >
> > [snip]
> >
> >> diff --git a/drivers/media/v4l2-core/v4l2-mc.c b/drivers/media/v4l2-core/v4l2-mc.c
> >> index 9ed480fe5b6e4762..98edd47b2f0ae747 100644
> >> --- a/drivers/media/v4l2-core/v4l2-mc.c
> >> +++ b/drivers/media/v4l2-core/v4l2-mc.c
> >> @@ -339,13 +339,14 @@ EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
> >> static int pipeline_pm_use_count(struct media_entity *entity,
> >> struct media_graph *graph)
> >> {
> >> + struct media_pad *pad;
> >> int use = 0;
> >>
> >> media_graph_walk_start(graph, entity->pads);
> >>
> >> - while ((entity = media_graph_walk_next(graph))) {
> >> - if (is_media_entity_v4l2_video_device(entity))
> >> - use += entity->use_count;
> >> + while ((pad = media_graph_walk_next(graph))) {
> >> + if (is_media_entity_v4l2_video_device(pad->entity))
> >> + use += pad->entity->use_count;
> >> }
> >>
> >> return use;
> >> @@ -398,7 +399,7 @@ static int pipeline_pm_power_one(struct media_entity *entity, int change)
> >> static int pipeline_pm_power(struct media_entity *entity, int change,
> >> struct media_graph *graph)
> >> {
> >> - struct media_entity *first = entity;
> >> + struct media_pad *tmp_pad, *pad;
> >
> > How about pad_err instead of tmp_pad, like in the exynos driver ? Or
> > possible first_pad to retain the "first" name ?
>
> Why? This is just a pad. It's an iterator. first_pad or pad_err are
> misleading as such. If you don't like tmp_pad, how about "pad2"? The "pad"
> variable is still used for a similar purpose.
The variable is a pad iterator used in the error path, which can't use
the pad pointer as we need to stop iterating when we reach it. first_pad
is a bad idea, but pad_err would convey the meaning.
> >
> >> int ret = 0;
> >>
> >> if (!change)
> >> @@ -406,19 +407,19 @@ static int pipeline_pm_power(struct media_entity *entity, int change,
> >>
> >> media_graph_walk_start(graph, entity->pads);
> >>
> >> - while (!ret && (entity = media_graph_walk_next(graph)))
> >> - if (is_media_entity_v4l2_subdev(entity))
> >> - ret = pipeline_pm_power_one(entity, change);
> >> + while (!ret && (pad = media_graph_walk_next(graph)))
> >> + if (is_media_entity_v4l2_subdev(pad->entity))
> >> + ret = pipeline_pm_power_one(pad->entity, change);
> >>
> >> if (!ret)
> >> return ret;
> >>
> >> - media_graph_walk_start(graph, first->pads);
> >> + media_graph_walk_start(graph, entity->pads);
> >>
> >> - while ((first = media_graph_walk_next(graph))
> >> - && first != entity)
> >> - if (is_media_entity_v4l2_subdev(first))
> >> - pipeline_pm_power_one(first, -change);
> >> + while ((tmp_pad = media_graph_walk_next(graph))
> >> + && tmp_pad != pad)
> >> + if (is_media_entity_v4l2_subdev(tmp_pad->entity))
> >> + pipeline_pm_power_one(tmp_pad->entity, -change);
> >>
> >> return ret;
> >> }
> >
> > [snip]
> >
> >> diff --git a/include/media/media-entity.h b/include/media/media-entity.h
> >> index 99c7606f01317741..cde6350d752bb0ae 100644
> >> --- a/include/media/media-entity.h
> >> +++ b/include/media/media-entity.h
> >> @@ -952,10 +952,11 @@ void media_graph_walk_start(struct media_graph *graph, struct media_pad *pad);
> >> * The graph structure must have been previously initialized with a call to
> >> * media_graph_walk_start().
> >> *
> >> - * Return: returns the next entity in the graph or %NULL if the whole graph
> >> - * have been traversed.
> >> + * Return: returns the next pad in the graph or %NULL if the whole
> >> + * graph have been traversed. The pad which is returned is the pad
> >
> > s/have been/has/been/
> > s/The pad which is returned/The returned pad/
> >
> >> + * through which a new entity is reached when parsing the graph.
> >
> > through which the entity was reached when walking the graph.
>
> I'd keep "new", as the intent is to underline that it's a new entity not
> yet reached while walking the graph.
"through which the new entity was reached when walking the graph" then ?
> >
> > With these addressed,
> >
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> >
> >> */
> >> -struct media_entity *media_graph_walk_next(struct media_graph *graph);
> >> +struct media_pad *media_graph_walk_next(struct media_graph *graph);
> >>
> >> /**
> >> * media_pipeline_start - Mark a pipeline as streaming
--
Regards,
Laurent Pinchart
