Hans Verkuil <hverk...@xs4all.nl> wrote on Mon [2016-Oct-17 16:17:15 +0200]:
> On 09/28/2016 11:20 PM, Benoit Parrot wrote:
> > From: Nikhil Devshatwar <nikhil...@ti.com>
> > 
> > Current VPE driver does not start the job until all the buffers for
> > a transaction are not queued. When running in multiple context, this might
> 
> I think this should be: s/not queued/queued/, right?

Yep, will fix that.

> 
> > increase the processing latency.
> > 
> > Alternate solution would be to try to continue the same context as long as
> > buffers for the transaction are ready; else switch the context. This may
> > increase number of context switches but it reduces latency significantly.
> > 
> > In this approach, the job_ready always succeeds as long as there are
> > buffers on the CAPTURE and OUTPUT stream. Processing may start immediately
> > as the first 2 iterations don't need extra source buffers. Shift all the
> > source buffers after each iteration and remove the oldest buffer.
> > 
> > Also, with this removes the constraint of pre buffering 3 buffers before
> > call to STREAMON in case of de-interlacing.
> > 
> > Signed-off-by: Nikhil Devshatwar <nikhil...@ti.com>
> > Signed-off-by: Benoit Parrot <bpar...@ti.com>
> > ---
> >  drivers/media/platform/ti-vpe/vpe.c | 32 ++++++++++++++++----------------
> >  1 file changed, 16 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/media/platform/ti-vpe/vpe.c 
> > b/drivers/media/platform/ti-vpe/vpe.c
> > index a0b29685fb69..9c38eff5df46 100644
> > --- a/drivers/media/platform/ti-vpe/vpe.c
> > +++ b/drivers/media/platform/ti-vpe/vpe.c
> > @@ -898,15 +898,14 @@ static struct vpe_ctx *file2ctx(struct file *file)
> >  static int job_ready(void *priv)
> >  {
> >     struct vpe_ctx *ctx = priv;
> > -   int needed = ctx->bufs_per_job;
> >  
> > -   if (ctx->deinterlacing && ctx->src_vbs[2] == NULL)
> > -           needed += 2;    /* need additional two most recent fields */
> > -
> > -   if (v4l2_m2m_num_src_bufs_ready(ctx->fh.m2m_ctx) < needed)
> > -           return 0;
> > -
> > -   if (v4l2_m2m_num_dst_bufs_ready(ctx->fh.m2m_ctx) < needed)
> > +   /*
> > +    * This check is needed as this might be called directly from driver
> > +    * When called by m2m framework, this will always satisy, but when
> 
> typo: satisfy

Will fix.

> 
> > +    * called from vpe_irq, this might fail. (src stream with zero buffers)
> > +    */
> > +   if (v4l2_m2m_num_src_bufs_ready(ctx->fh.m2m_ctx) <= 0 ||
> > +           v4l2_m2m_num_dst_bufs_ready(ctx->fh.m2m_ctx) <= 0)
> >             return 0;
> >  
> >     return 1;
> > @@ -1116,19 +1115,20 @@ static void device_run(void *priv)
> >     struct sc_data *sc = ctx->dev->sc;
> >     struct vpe_q_data *d_q_data = &ctx->q_data[Q_DATA_DST];
> >  
> > -   if (ctx->deinterlacing && ctx->src_vbs[2] == NULL) {
> > -           ctx->src_vbs[2] = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > -           WARN_ON(ctx->src_vbs[2] == NULL);
> > -           ctx->src_vbs[1] = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > -           WARN_ON(ctx->src_vbs[1] == NULL);
> > -   }
> > -
> >     ctx->src_vbs[0] = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> >     WARN_ON(ctx->src_vbs[0] == NULL);
> >     ctx->dst_vb = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> >     WARN_ON(ctx->dst_vb == NULL);
> >  
> >     if (ctx->deinterlacing) {
> > +
> > +           if (ctx->src_vbs[2] == NULL) {
> > +                   ctx->src_vbs[2] = ctx->src_vbs[0];
> > +                   WARN_ON(ctx->src_vbs[2] == NULL);
> > +                   ctx->src_vbs[1] = ctx->src_vbs[0];
> > +                   WARN_ON(ctx->src_vbs[1] == NULL);
> > +           }
> > +
> >             /*
> >              * we have output the first 2 frames through line average, we
> >              * now switch to EDI de-interlacer
> > @@ -1349,7 +1349,7 @@ static irqreturn_t vpe_irq(int irq_vpe, void *data)
> >     }
> >  
> >     ctx->bufs_completed++;
> > -   if (ctx->bufs_completed < ctx->bufs_per_job) {
> > +   if (ctx->bufs_completed < ctx->bufs_per_job && job_ready(ctx)) {
> >             device_run(ctx);
> >             goto handled;
> >     }
> > 
> 
> Regards,
> 
>       Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to