[PATCH v2 01/14] v4l: vsp1: Fill display list headers without holding dlm spinlock

[Laurent Pinchart]

The display list headers are filled using information from the display
list only. Lower the display list manager spinlock contention by filling
the headers without holding the lock.

Signed-off-by: Laurent Pinchart 
---
 drivers/media/platform/vsp1/vsp1_dl.c | 6 --
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/vsp1/vsp1_dl.c 
b/drivers/media/platform/vsp1/vsp1_dl.c
index aaf17b13fd78..dc47e236c780 100644
--- a/drivers/media/platform/vsp1/vsp1_dl.c
+++ b/drivers/media/platform/vsp1/vsp1_dl.c
@@ -483,8 +483,6 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl)
unsigned long flags;
bool update;
 
-   spin_lock_irqsave(&dlm->lock, flags);
-
if (dl->dlm->mode == VSP1_DL_MODE_HEADER) {
struct vsp1_dl_list *dl_child;
 
@@ -501,7 +499,11 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl)
 
vsp1_dl_list_fill_header(dl_child, last);
}
+   }
 
+   spin_lock_irqsave(&dlm->lock, flags);
+
+   if (dl->dlm->mode == VSP1_DL_MODE_HEADER) {
/*
 * Commit the head display list to hardware. Chained headers
 * will auto-start.
-- 
Regards,

Laurent Pinchart

Re: [PATCH v2 01/14] v4l: vsp1: Fill display list headers without holding dlm spinlock

[Kieran Bingham]

Hi Laurent,

Starts easy ... (I haven't gone through these in numerical order of course :D)

On 26/06/17 19:12, Laurent Pinchart wrote:
> The display list headers are filled using information from the display
> list only. Lower the display list manager spinlock contention by filling
> the headers without holding the lock.
> 
> Signed-off-by: Laurent Pinchart 

Reviewed-by: Kieran Bingham 

> ---
>  drivers/media/platform/vsp1/vsp1_dl.c | 6 --
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/vsp1/vsp1_dl.c 
> b/drivers/media/platform/vsp1/vsp1_dl.c
> index aaf17b13fd78..dc47e236c780 100644
> --- a/drivers/media/platform/vsp1/vsp1_dl.c
> +++ b/drivers/media/platform/vsp1/vsp1_dl.c
> @@ -483,8 +483,6 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl)
>   unsigned long flags;
>   bool update;
>  
> - spin_lock_irqsave(&dlm->lock, flags);
> -
>   if (dl->dlm->mode == VSP1_DL_MODE_HEADER) {
>   struct vsp1_dl_list *dl_child;
>  
> @@ -501,7 +499,11 @@ void vsp1_dl_list_commit(struct vsp1_dl_list *dl)
>  
>   vsp1_dl_list_fill_header(dl_child, last);
>   }
> + }
>  
> + spin_lock_irqsave(&dlm->lock, flags);
> +
> + if (dl->dlm->mode == VSP1_DL_MODE_HEADER) {
>   /*
>* Commit the head display list to hardware. Chained headers
>* will auto-start.
> 

Re: [PATCH v2 01/14] v4l: vsp1: Fill display list headers without holding dlm spinlock

[Mauro Carvalho Chehab]

Em Thu, 13 Jul 2017 13:48:40 +0100
Kieran Bingham  escreveu:

> Hi Laurent,
> 
> Starts easy ... (I haven't gone through these in numerical order of course :D)
> 
> On 26/06/17 19:12, Laurent Pinchart wrote:
> > The display list headers are filled using information from the display
> > list only. Lower the display list manager spinlock contention by filling
> > the headers without holding the lock.
> > 
> > Signed-off-by: Laurent Pinchart  
> >  
> 
> Reviewed-by: Kieran Bingham 
Acked-by: Mauro Carvalho Chehab 

Thanks,
Mauro