On Thu, Apr 14, 2016 at 06:29:38PM -0700, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
>
> Now a drm_pending_event can either send a real drm_event or signal a
> fence, or both. It allow us to signal via fences when the buffer is
> displayed on the screen. Which in turn means that the previous buffer
> is not in use anymore and can be freed or sent back to another driver
> for processing.
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
Do you have atomic igt testcase that exercise all the combinations of
drm_event and in/out-fences and make sure it all keeps working? Tomeu
already converted that over to be a generic testcase.
> ---
> drivers/gpu/drm/drm_atomic.c | 19 +++++++++++++------
> drivers/gpu/drm/drm_fops.c | 5 +++--
> drivers/gpu/drm/drm_irq.c | 7 +++++++
> include/drm/drmP.h | 1 +
> 4 files changed, 24 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 6702502..0b95526 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -1431,7 +1431,8 @@ EXPORT_SYMBOL(drm_atomic_async_commit);
> */
>
> static struct drm_pending_vblank_event *create_vblank_event(
> - struct drm_device *dev, struct drm_file *file_priv, uint64_t
> user_data)
> + struct drm_device *dev, struct drm_file *file_priv,
> + struct fence *fence, uint64_t user_data)
> {
> struct drm_pending_vblank_event *e = NULL;
> int ret;
> @@ -1444,12 +1445,17 @@ static struct drm_pending_vblank_event
> *create_vblank_event(
> e->event.base.length = sizeof(e->event);
> e->event.user_data = user_data;
>
> - ret = drm_event_reserve_init(dev, file_priv, &e->base, &e->event.base);
> - if (ret) {
> - kfree(e);
> - return NULL;
> + if (file_priv) {
> + ret = drm_event_reserve_init(dev, file_priv, &e->base,
> + &e->event.base);
> + if (ret) {
> + kfree(e);
> + return NULL;
> + }
> }
>
> + e->base.fence = fence;
> +
> return e;
> }
>
> @@ -1676,7 +1682,8 @@ retry:
> for_each_crtc_in_state(state, crtc, crtc_state, i) {
> struct drm_pending_vblank_event *e;
>
> - e = create_vblank_event(dev, file_priv, arg->user_data);
> + e = create_vblank_event(dev, file_priv, NULL,
> + arg->user_data);
> if (!e) {
> ret = -ENOMEM;
> goto out;
> diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
> index aeef58e..38def49 100644
> --- a/drivers/gpu/drm/drm_fops.c
> +++ b/drivers/gpu/drm/drm_fops.c
> @@ -801,8 +801,9 @@ void drm_send_event_locked(struct drm_device *dev, struct
> drm_pending_event *e)
> {
> assert_spin_locked(&dev->event_lock);
>
> - if (!e->file_priv) {
> - e->destroy(e);
> + if (!e->file_priv || !e->event) {
This would be a bug: e->file_priv != NULL iff e->event != NULL. How did
this happen?
> + if (e->destroy)
> + e->destroy(e);
> return;
> }
>
> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
> index 3c1a6f1..0c5d7cb 100644
> --- a/drivers/gpu/drm/drm_irq.c
> +++ b/drivers/gpu/drm/drm_irq.c
> @@ -41,6 +41,7 @@
>
> #include <linux/vgaarb.h>
> #include <linux/export.h>
> +#include <linux/fence.h>
>
> /* Access macro for slots in vblank timestamp ringbuffer. */
> #define vblanktimestamp(dev, pipe, count) \
> @@ -1124,6 +1125,12 @@ void drm_send_vblank_event(struct drm_device *dev,
> unsigned int pipe,
> now = get_drm_timestamp();
> }
> e->pipe = pipe;
> +
> + if (e->base.fence) {
> + fence_signal(e->base.fence);
> + fence_put(e->base.fence);
> + }
I'd put this into drm_send_event_locked even. In case we send out fences
for other events too (e.g. exynos uses drm_event for rendering ...).
-Daniel
> +
> send_vblank_event(dev, e, seq, &now);
> }
> EXPORT_SYMBOL(drm_send_vblank_event);
> diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> index 3c8422c..8f83c2a 100644
> --- a/include/drm/drmP.h
> +++ b/include/drm/drmP.h
> @@ -282,6 +282,7 @@ struct drm_ioctl_desc {
> /* Event queued up for userspace to read */
> struct drm_pending_event {
> struct drm_event *event;
> + struct fence *fence;
> struct list_head link;
> struct list_head pending_link;
> struct drm_file *file_priv;
> --
> 2.5.5
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
