On Wed, Sep 05, 2018 at 04:03:26PM +0200, Daniel Vetter wrote:

On Tue, Sep 04, 2018 at 12:18:17AM +0300, Haneen Mohammed wrote:

...

crtc_state is accessed by both vblank_handle() and the ordered work_struct handle vkms_crc_work_handle() to retrieve and or update the frame number for computed CRC.

Since work_struct can fail, add frame_end to account for missing frame numbers.

Use (frame_[start/end]) for synchronization between hrtimer callback and ordered work_struct handle.

This patch passes the following subtests from igt kms_pipe_crc_basic test: bad-source, read-crc-pipe-A, read-crc-pipe-A-frame-sequence, nonblocking-crc-pipe-A, nonblocking-crc-pipe-A-frame-sequence

Signed-off-by: Haneen Mohammed hamohammed.sa@gmail.com

v2:

• use u64 with spinlock instead of atomic_t
• add out label for common exit routine @vkms_crc_work_handle()

Yup I think that looks good, thanks for your patch. Applied.

btw, do you still plan to type up a vkms.rst for documentation, so that we could put a few of the todo items there? Or should I do that? Next outreachy round starts soon, we need to get this ready. -Daniel

I did prepare a patch for vkms.rst but since most of the todos I've so far are related to the cursor patch, I planed to send it after I submit the cursor patch. I'll send both out by the end of today.

...

drivers/gpu/drm/vkms/vkms_crc.c | 36 ++++++++++++++++++++++++++++++-- drivers/gpu/drm/vkms/vkms_crtc.c | 16 ++++++++++++-- drivers/gpu/drm/vkms/vkms_drv.h | 8 +++++-- 3 files changed, 54 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_crc.c b/drivers/gpu/drm/vkms/vkms_crc.c index ed47d67cecd6..68db42f15086 100644 --- a/drivers/gpu/drm/vkms/vkms_crc.c +++ b/drivers/gpu/drm/vkms/vkms_crc.c @@ -34,6 +34,15 @@ static uint32_t _vkms_get_crc(struct vkms_crc_data *crc_data) return crc; }

+/**

• • vkms_crc_work_handle - ordered work_struct to compute CRC
• • @work: work_struct
• • Work handler for computing CRCs. work_struct scheduled in
• • an ordered workqueue that's periodically scheduled to run by
• • _vblank_handle() and flushed at vkms_atomic_crtc_destroy_state().
• */

void vkms_crc_work_handle(struct work_struct *work) { struct vkms_crtc_state *crtc_state = container_of(work, @@ -45,8 +54,18 @@ void vkms_crc_work_handle(struct work_struct *work) output); struct vkms_crc_data *primary_crc = NULL; struct drm_plane *plane;

• u32 crc32 = 0;

• u64 frame_start, frame_end;

• unsigned long flags;

• spin_lock_irqsave(&out->state_lock, flags);

• frame_start = crtc_state->frame_start;

• frame_end = crtc_state->frame_end;

• spin_unlock_irqrestore(&out->state_lock, flags);

• /* _vblank_handle() hasn't updated frame_start yet */

• if (!frame_start || frame_start == frame_end)

• goto out;
  
  

  drm_for_each_plane(plane, &vdev->drm) { struct vkms_plane_state *vplane_state;

@@ -67,7 +86,20 @@ void vkms_crc_work_handle(struct work_struct *work) if (primary_crc) crc32 = _vkms_get_crc(primary_crc);

• drm_crtc_add_crc_entry(crtc, true, crtc_state->n_frame, &crc32);

• frame_end = drm_crtc_accurate_vblank_count(crtc);
• /* queue_work can fail to schedule crc_work; add crc for

• * missing frames
  

• */
  

• while (frame_start <= frame_end)

• drm_crtc_add_crc_entry(crtc, true, frame_start++, &crc32);
  

+out:

• /* to avoid using the same value for frame number again */
• spin_lock_irqsave(&out->state_lock, flags);
• crtc_state->frame_end = frame_end;
• crtc_state->frame_start = 0;
• spin_unlock_irqrestore(&out->state_lock, flags);

}

static int vkms_crc_parse_source(const char *src_name, bool *enabled) diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c index 9d0b1a325a78..177bbcb38306 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -22,8 +22,19 @@ static void _vblank_handle(struct vkms_output *output) DRM_ERROR("vkms failure on handling vblank");

if (state && output->crc_enabled) {

• state->n_frame = drm_crtc_accurate_vblank_count(crtc);
  

• queue_work(output->crc_workq, &state->crc_work);
  

• u64 frame = drm_crtc_accurate_vblank_count(crtc);
  

• /* update frame_start only if a queued vkms_crc_work_handle()
  

•  * has read the data
  

•  */
  

• spin_lock(&output->state_lock);
  

• if (!state->frame_start)
  

• 	state->frame_start = frame;
  

• spin_unlock(&output->state_lock);
  

• ret = queue_work(output->crc_workq, &state->crc_work);
  

• if (!ret)
  

• 	DRM_WARN("failed to queue vkms_crc_work_handle");
  

  }

  spin_unlock(&output->lock);

@@ -211,6 +222,7 @@ int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc, drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);

spin_lock_init(&vkms_out->lock);

• spin_lock_init(&vkms_out->state_lock);

  vkms_out->crc_workq = alloc_ordered_workqueue("vkms_crc_workq", 0);

diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h index 2017a2ccc43d..80af6d3a65e7 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.h +++ b/drivers/gpu/drm/vkms/vkms_drv.h @@ -39,12 +39,14 @@ struct vkms_plane_state {

• vkms_crtc_state - Driver specific CRTC state
• @base: base CRTC state
• @crc_work: work struct to compute and add CRC entries

• • @n_frame: frame number for computed CRC

• • @n_frame_start: start frame number for computed CRC
• • @n_frame_end: end frame number for computed CRC
  */

struct vkms_crtc_state { struct drm_crtc_state base; struct work_struct crc_work;

• unsigned int n_frame;

• u64 frame_start;
• u64 frame_end;

};

struct vkms_output { @@ -59,6 +61,8 @@ struct vkms_output { struct workqueue_struct *crc_workq; /* protects concurrent access to crc_data */ spinlock_t lock;

• /* protects concurrent access to crtc_state */
• spinlock_t state_lock;

};

struct vkms_device {

2.17.1

-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch