Hi Tomi and Sakari,
Another comment (probably more annoying).
On Fri, Jan 07, 2022 at 09:52:06PM +0200, Laurent Pinchart wrote:
> On Tue, Nov 30, 2021 at 04:15:10PM +0200, Tomi Valkeinen wrote:
> > From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> >
> > This moves the pipe and stream_count fields from struct media_entity to
> > struct media_pad. Effectively streams become pad-specific rather than
> > being entity specific, allowing several independent streams to traverse a
> > single entity and an entity to be part of several streams.
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> > Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> >
> > - Update documentation to use 'pads'
> > - Use the media pad iterator in media_entity.c
> > - Update rcar-dma.c to use the new per-pad stream count
> > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> >
> > - Fix cleanup in the error path of __media_pipeline_start()
> > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > ---
> > drivers/media/mc/mc-entity.c | 68 +++++++++++--------
> > drivers/media/platform/exynos4-is/fimc-isp.c | 2 +-
> > drivers/media/platform/exynos4-is/fimc-lite.c | 2 +-
> > drivers/media/platform/omap3isp/isp.c | 2 +-
> > drivers/media/platform/omap3isp/ispvideo.c | 2 +-
> > drivers/media/platform/omap3isp/ispvideo.h | 2 +-
> > drivers/media/platform/rcar-vin/rcar-core.c | 16 +++--
> > drivers/media/platform/rcar-vin/rcar-dma.c | 2 +-
> > drivers/media/platform/xilinx/xilinx-dma.c | 2 +-
> > drivers/media/platform/xilinx/xilinx-dma.h | 2 +-
> > drivers/staging/media/imx/imx-media-utils.c | 2 +-
> > drivers/staging/media/omap4iss/iss.c | 2 +-
> > drivers/staging/media/omap4iss/iss_video.c | 2 +-
> > drivers/staging/media/omap4iss/iss_video.h | 2 +-
> > include/media/media-entity.h | 21 +++---
> > 15 files changed, 74 insertions(+), 55 deletions(-)
> >
> > diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
> > index 2b438c481812..8ad4cb845f4a 100644
> > --- a/drivers/media/mc/mc-entity.c
> > +++ b/drivers/media/mc/mc-entity.c
> > @@ -424,24 +424,30 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
> >
> > while ((pad = media_graph_walk_next(graph))) {
> > struct media_entity *entity = pad->entity;
> > + bool skip_validation = pad->pipe != NULL;
> > + struct media_pad *iter;
> >
> > DECLARE_BITMAP(active, MEDIA_ENTITY_MAX_PADS);
> > DECLARE_BITMAP(has_no_links, MEDIA_ENTITY_MAX_PADS);
> >
> > - entity->stream_count++;
> > + ret = 0;
> >
> > - if (entity->pipe && entity->pipe != pipe) {
> > - pr_err("Pipe active for %s. Can't start for %s\n",
> > - entity->name,
> > - pad_err->entity->name);
> > - ret = -EBUSY;
> > - goto error;
> > + media_entity_for_each_pad(entity, iter) {
> > + if (iter->pipe && iter->pipe != pipe) {
> > + pr_err("Pipe active for %s. Can't start for %s\n",
> > + entity->name, iter->entity->name);
>
> 'iter' is a pad of 'entity'. As 'entity' is set to 'pad->entity',
> 'entity' and 'iter->entity' are the same. The message should be
> reworked.
>
> > + ret = -EBUSY;
> > + } else {
> > + iter->pipe = pipe;
> > + }
> > + iter->stream_count++;
> > }
> >
> > - entity->pipe = pipe;
> > + if (ret)
> > + goto error;
> >
> > - /* Already streaming --- no need to check. */
> > - if (entity->stream_count > 1)
> > + /* Already part of the pipeline, skip validation. */
> > + if (skip_validation)
> > continue;
> >
> > if (!entity->ops || !entity->ops->link_validate)
> > @@ -510,20 +516,23 @@ __must_check int __media_pipeline_start(struct media_entity *entity,
> > media_graph_walk_start(graph, pad_err);
> >
> > while ((pad_err = media_graph_walk_next(graph))) {
> > - struct media_entity *entity_err = pad_err->entity;
> > -
> > - /* Sanity check for negative stream_count */
> > - if (!WARN_ON_ONCE(entity_err->stream_count <= 0)) {
> > - entity_err->stream_count--;
> > - if (entity_err->stream_count == 0)
> > - entity_err->pipe = NULL;
> > + struct media_entity *entity = pad_err->entity;
> > + struct media_pad *iter;
> > +
> > + media_entity_for_each_pad(entity, iter) {
> > + /* Sanity check for negative stream_count */
> > + if (!WARN_ON_ONCE(iter->stream_count <= 0)) {
> > + --iter->stream_count;
> > + if (iter->stream_count == 0)
> > + iter->pipe = NULL;
> > + }
> > }
> >
> > /*
> > * We haven't increased stream_count further than this
> > * so we quit here.
> > */
> > - if (pad_err == pad)
> > + if (pad_err->entity == pad->entity)
> > break;
> > }
> >
> > @@ -550,7 +559,7 @@ EXPORT_SYMBOL_GPL(media_pipeline_start);
> >
> > void __media_pipeline_stop(struct media_entity *entity)
> > {
> > - struct media_pipeline *pipe = entity->pipe;
> > + struct media_pipeline *pipe = entity->pads->pipe;
> > struct media_graph *graph = &pipe->graph;
> > struct media_pad *pad;
> >
> > @@ -565,12 +574,15 @@ void __media_pipeline_stop(struct media_entity *entity)
> >
> > while ((pad = media_graph_walk_next(graph))) {
> > struct media_entity *entity = pad->entity;
> > -
> > - /* Sanity check for negative stream_count */
> > - if (!WARN_ON_ONCE(entity->stream_count <= 0)) {
> > - entity->stream_count--;
> > - if (entity->stream_count == 0)
> > - entity->pipe = NULL;
> > + struct media_pad *iter;
> > +
> > + media_entity_for_each_pad(entity, iter) {
> > + /* Sanity check for negative stream_count */
> > + if (!WARN_ON_ONCE(iter->stream_count <= 0)) {
> > + iter->stream_count--;
> > + if (iter->stream_count == 0)
> > + iter->pipe = NULL;
> > + }
> > }
> > }
> >
> > @@ -840,7 +852,7 @@ int __media_entity_setup_link(struct media_link *link, u32 flags)
> > {
> > const u32 mask = MEDIA_LNK_FL_ENABLED;
> > struct media_device *mdev;
> > - struct media_entity *source, *sink;
> > + struct media_pad *source, *sink;
> > int ret = -EBUSY;
> >
> > if (link == NULL)
> > @@ -856,8 +868,8 @@ int __media_entity_setup_link(struct media_link *link, u32 flags)
> > if (link->flags == flags)
> > return 0;
> >
> > - source = link->source->entity;
> > - sink = link->sink->entity;
> > + source = link->source;
> > + sink = link->sink;
> >
> > if (!(link->flags & MEDIA_LNK_FL_DYNAMIC) &&
> > (source->stream_count || sink->stream_count))
> > diff --git a/drivers/media/platform/exynos4-is/fimc-isp.c b/drivers/media/platform/exynos4-is/fimc-isp.c
> > index 855235bea46d..80274e29ccc5 100644
> > --- a/drivers/media/platform/exynos4-is/fimc-isp.c
> > +++ b/drivers/media/platform/exynos4-is/fimc-isp.c
> > @@ -226,7 +226,7 @@ static int fimc_isp_subdev_set_fmt(struct v4l2_subdev *sd,
> > }
> > }
> > } else {
> > - if (sd->entity.stream_count == 0) {
> > + if (sd->entity.pads->stream_count == 0) {
> > if (fmt->pad == FIMC_ISP_SD_PAD_SINK) {
> > struct v4l2_subdev_format format = *fmt;
> >
> > diff --git a/drivers/media/platform/exynos4-is/fimc-lite.c b/drivers/media/platform/exynos4-is/fimc-lite.c
> > index aaa3af0493ce..67bfb1ad2ba2 100644
> > --- a/drivers/media/platform/exynos4-is/fimc-lite.c
> > +++ b/drivers/media/platform/exynos4-is/fimc-lite.c
> > @@ -1073,7 +1073,7 @@ static int fimc_lite_subdev_set_fmt(struct v4l2_subdev *sd,
> > mutex_lock(&fimc->lock);
> >
> > if ((atomic_read(&fimc->out_path) == FIMC_IO_ISP &&
> > - sd->entity.stream_count > 0) ||
> > + sd->entity.pads->stream_count > 0) ||
> > (atomic_read(&fimc->out_path) == FIMC_IO_DMA &&
> > vb2_is_busy(&fimc->vb_queue))) {
> > mutex_unlock(&fimc->lock);
> > diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c
> > index 20f59c59ff8a..28aab16d7662 100644
> > --- a/drivers/media/platform/omap3isp/isp.c
> > +++ b/drivers/media/platform/omap3isp/isp.c
> > @@ -936,7 +936,7 @@ static int isp_pipeline_is_last(struct media_entity *me)
> > struct isp_pipeline *pipe;
> > struct media_pad *pad;
> >
> > - if (!me->pipe)
> > + if (!me->pads->pipe)
> > return 0;
> > pipe = to_isp_pipeline(me);
> > if (pipe->stream_state == ISP_PIPELINE_STREAM_STOPPED)
> > diff --git a/drivers/media/platform/omap3isp/ispvideo.c b/drivers/media/platform/omap3isp/ispvideo.c
> > index 5c1cbb1a9003..a8438040c4aa 100644
> > --- a/drivers/media/platform/omap3isp/ispvideo.c
> > +++ b/drivers/media/platform/omap3isp/ispvideo.c
> > @@ -1094,7 +1094,7 @@ isp_video_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
> > /* Start streaming on the pipeline. No link touching an entity in the
> > * pipeline can be activated or deactivated once streaming is started.
> > */
> > - pipe = video->video.entity.pipe
> > + pipe = video->video.entity.pads->pipe
> > ? to_isp_pipeline(&video->video.entity) : &video->pipe;
> >
> > ret = media_entity_enum_init(&pipe->ent_enum, &video->isp->media_dev);
> > diff --git a/drivers/media/platform/omap3isp/ispvideo.h b/drivers/media/platform/omap3isp/ispvideo.h
> > index a0908670c0cf..4c9c5b719ec5 100644
> > --- a/drivers/media/platform/omap3isp/ispvideo.h
> > +++ b/drivers/media/platform/omap3isp/ispvideo.h
> > @@ -100,7 +100,7 @@ struct isp_pipeline {
> > };
> >
> > #define to_isp_pipeline(__e) \
> > - container_of((__e)->pipe, struct isp_pipeline, pipe)
> > + container_of((__e)->pads->pipe, struct isp_pipeline, pipe)
> >
> > static inline int isp_pipeline_ready(struct isp_pipeline *pipe)
> > {
> > diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> > index 33957cc9118c..e59453d6b7c3 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-core.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> > @@ -132,13 +132,17 @@ static int rvin_group_link_notify(struct media_link *link, u32 flags,
> > return 0;
> >
> > /*
> > - * Don't allow link changes if any entity in the graph is
> > - * streaming, modifying the CHSEL register fields can disrupt
> > - * running streams.
> > + * Don't allow link changes if any stream in the graph is active as
> > + * modifying the CHSEL register fields can disrupt running streams.
> > */
> > - media_device_for_each_entity(entity, &group->mdev)
> > - if (entity->stream_count)
> > - return -EBUSY;
> > + media_device_for_each_entity(entity, &group->mdev) {
> > + struct media_pad *iter;
> > +
> > + media_entity_for_each_pad(entity, iter) {
> > + if (iter->stream_count)
> > + return -EBUSY;
> > + }
> > + }
> >
> > mutex_lock(&group->lock);
> >
> > diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
> > index f5f722ab1d4e..80b7ae47d165 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-dma.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-dma.c
> > @@ -1231,7 +1231,7 @@ static int rvin_set_stream(struct rvin_dev *vin, int on)
> > */
> > mdev = vin->vdev.entity.graph_obj.mdev;
> > mutex_lock(&mdev->graph_mutex);
> > - pipe = sd->entity.pipe ? sd->entity.pipe : &vin->vdev.pipe;
> > + pipe = sd->entity.pads->pipe ? sd->entity.pads->pipe : &vin->vdev.pipe;
> > ret = __media_pipeline_start(&vin->vdev.entity, pipe);
> > mutex_unlock(&mdev->graph_mutex);
> > if (ret)
> > diff --git a/drivers/media/platform/xilinx/xilinx-dma.c b/drivers/media/platform/xilinx/xilinx-dma.c
> > index d33f99c6ffa4..03ee19d00041 100644
> > --- a/drivers/media/platform/xilinx/xilinx-dma.c
> > +++ b/drivers/media/platform/xilinx/xilinx-dma.c
> > @@ -402,7 +402,7 @@ static int xvip_dma_start_streaming(struct vb2_queue *vq, unsigned int count)
> > * Use the pipeline object embedded in the first DMA object that starts
> > * streaming.
> > */
> > - pipe = dma->video.entity.pipe
> > + pipe = dma->video.entity.pads->pipe
> > ? to_xvip_pipeline(&dma->video.entity) : &dma->pipe;
> >
> > ret = media_pipeline_start(&dma->video.entity, &pipe->pipe);
> > diff --git a/drivers/media/platform/xilinx/xilinx-dma.h b/drivers/media/platform/xilinx/xilinx-dma.h
> > index 2378bdae57ae..69ced71a5696 100644
> > --- a/drivers/media/platform/xilinx/xilinx-dma.h
> > +++ b/drivers/media/platform/xilinx/xilinx-dma.h
> > @@ -47,7 +47,7 @@ struct xvip_pipeline {
> >
> > static inline struct xvip_pipeline *to_xvip_pipeline(struct media_entity *e)
> > {
> > - return container_of(e->pipe, struct xvip_pipeline, pipe);
> > + return container_of(e->pads->pipe, struct xvip_pipeline, pipe);
> > }
> >
> > /**
> > diff --git a/drivers/staging/media/imx/imx-media-utils.c b/drivers/staging/media/imx/imx-media-utils.c
> > index 6f90acf9c725..535da4dda3c6 100644
> > --- a/drivers/staging/media/imx/imx-media-utils.c
> > +++ b/drivers/staging/media/imx/imx-media-utils.c
> > @@ -913,7 +913,7 @@ int imx_media_pipeline_set_stream(struct imx_media_dev *imxmd,
> > __media_pipeline_stop(entity);
> > } else {
> > v4l2_subdev_call(sd, video, s_stream, 0);
> > - if (entity->pipe)
> > + if (entity->pads->pipe)
> > __media_pipeline_stop(entity);
> > }
> >
> > diff --git a/drivers/staging/media/omap4iss/iss.c b/drivers/staging/media/omap4iss/iss.c
> > index 68588e9dab0b..4c6f25aa8b57 100644
> > --- a/drivers/staging/media/omap4iss/iss.c
> > +++ b/drivers/staging/media/omap4iss/iss.c
> > @@ -548,7 +548,7 @@ static int iss_pipeline_is_last(struct media_entity *me)
> > struct iss_pipeline *pipe;
> > struct media_pad *pad;
> >
> > - if (!me->pipe)
> > + if (!me->pads->pipe)
> > return 0;
> > pipe = to_iss_pipeline(me);
> > if (pipe->stream_state == ISS_PIPELINE_STREAM_STOPPED)
> > diff --git a/drivers/staging/media/omap4iss/iss_video.c b/drivers/staging/media/omap4iss/iss_video.c
> > index 8c25ad73a81e..b74f7891711d 100644
> > --- a/drivers/staging/media/omap4iss/iss_video.c
> > +++ b/drivers/staging/media/omap4iss/iss_video.c
> > @@ -871,7 +871,7 @@ iss_video_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
> > * Start streaming on the pipeline. No link touching an entity in the
> > * pipeline can be activated or deactivated once streaming is started.
> > */
> > - pipe = pad->entity->pipe
> > + pipe = pad->pipe
> > ? to_iss_pipeline(pad->entity) : &video->pipe;
> > pipe->external = NULL;
> > pipe->external_rate = 0;
> > diff --git a/drivers/staging/media/omap4iss/iss_video.h b/drivers/staging/media/omap4iss/iss_video.h
> > index 526281bf0051..9b8ec27bf87d 100644
> > --- a/drivers/staging/media/omap4iss/iss_video.h
> > +++ b/drivers/staging/media/omap4iss/iss_video.h
> > @@ -91,7 +91,7 @@ struct iss_pipeline {
> > };
> >
> > #define to_iss_pipeline(__e) \
> > - container_of((__e)->pipe, struct iss_pipeline, pipe)
> > + container_of((__e)->pads->pipe, struct iss_pipeline, pipe)
> >
> > static inline int iss_pipeline_ready(struct iss_pipeline *pipe)
> > {
> > diff --git a/include/media/media-entity.h b/include/media/media-entity.h
> > index 5f6eed24e63f..c9d97c902d05 100644
> > --- a/include/media/media-entity.h
> > +++ b/include/media/media-entity.h
> > @@ -180,15 +180,24 @@ enum media_pad_signal_type {
> > *
> > * @graph_obj: Embedded structure containing the media object common data
> > * @entity: Entity this pad belongs to
> > + * @pipe: Pipeline this pad belongs to
> > + * @stream_count: Stream count for the pad
> > * @index: Pad index in the entity pads array, numbered from 0 to n
> > * @sig_type: Type of the signal inside a media pad
> > * @flags: Pad flags, as defined in
> > * :ref:`include/uapi/linux/media.h <media_header>`
> > * (seek for ``MEDIA_PAD_FL_*``)
> > + * .. note::
> > + *
> > + * @stream_count reference count must never be negative, but is a signed
> > + * integer on purpose: a simple ``WARN_ON(<0)`` check can be used to
> > + * detect reference count bugs that would make it negative.
> > */
> > struct media_pad {
> > struct media_gobj graph_obj; /* must be first field in struct */
> > struct media_entity *entity;
> > + struct media_pipeline *pipe;
> > + int stream_count;
This doesn't seem enough to me. When carrying multiple streams, it seems
to me that a pad can be part of multiple pipelines. This can be the case
for instance of the source pad of a CSI-2 transmitter or the sink pad of
a CSI-2 receiver.
What do you think ?
> > u16 index;
> > enum media_pad_signal_type sig_type;
> > unsigned long flags;
> > @@ -267,9 +276,7 @@ enum media_entity_type {
> > * @pads: Pads array with the size defined by @num_pads.
> > * @links: List of data links.
> > * @ops: Entity operations.
> > - * @stream_count: Stream count for the entity.
> > * @use_count: Use count for the entity.
> > - * @pipe: Pipeline this entity belongs to.
> > * @info: Union with devnode information. Kept just for backward
> > * compatibility.
> > * @info.dev: Contains device major and minor info.
> > @@ -282,10 +289,9 @@ enum media_entity_type {
> > *
> > * .. note::
> > *
> > - * @stream_count and @use_count reference counts must never be
> > - * negative, but are signed integers on purpose: a simple ``WARN_ON(<0)``
> > - * check can be used to detect reference count bugs that would make them
> > - * negative.
> > + * @use_count reference count must never be negative, but is a signed
> > + * integer on purpose: a simple ``WARN_ON(<0)`` check can be used to
> > + * detect reference count bugs that would make it negative.
> > */
> > struct media_entity {
> > struct media_gobj graph_obj; /* must be first field in struct */
> > @@ -304,11 +310,8 @@ struct media_entity {
> >
> > const struct media_entity_operations *ops;
> >
> > - int stream_count;
> > int use_count;
> >
> > - struct media_pipeline *pipe;
> > -
> > union {
> > struct {
> > u32 major;
--
Regards,
Laurent Pinchart
