While I haven't seen us take too long in nv50_crc_ctx_flip_work() outside of users with kernel logging on a serial port, it probably would be a good idea to check how long we take just in case we need to go faster in the future.

Cc: Martin Peres martin.peres@free.fr Cc: Jeremy Cline jcline@redhat.com Cc: Simon Ser contact@emersion.fr Signed-off-by: Lyude Paul lyude@redhat.com --- drivers/gpu/drm/nouveau/dispnv50/crc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv50/crc.c b/drivers/gpu/drm/nouveau/dispnv50/crc.c index 3c50b29a37ff..ef942248345c 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/crc.c +++ b/drivers/gpu/drm/nouveau/dispnv50/crc.c @@ -86,6 +86,8 @@ static void nv50_crc_ctx_flip_work(struct kthread_work *base) struct drm_crtc *crtc = &head->base.base; struct drm_device *dev = crtc->dev; struct nv50_disp *disp = nv50_disp(dev); + const uint64_t start_vbl = drm_crtc_vblank_count(crtc); + uint64_t end_vbl; u8 new_idx = crc->ctx_idx ^ 1;

/* @@ -94,9 +96,7 @@ static void nv50_crc_ctx_flip_work(struct kthread_work *base) */ if (!mutex_trylock(&disp->mutex)) { drm_dbg_kms(dev, "Lock contended, delaying CRC ctx flip for %s\n", crtc->name); - drm_vblank_work_schedule(work, - drm_crtc_vblank_count(crtc) + 1, - true); + drm_vblank_work_schedule(work, start_vbl + 1, true); return; }

@@ -107,6 +107,12 @@ static void nv50_crc_ctx_flip_work(struct kthread_work *base) nv50_crc_program_ctx(head, &crc->ctx[new_idx]); mutex_unlock(&disp->mutex);

+ end_vbl = drm_crtc_vblank_count(crtc); + if (unlikely(end_vbl != start_vbl)) + NV_ERROR(nouveau_drm(dev), + "Failed to flip CRC context on %s on time (%llu > %llu)\n", + crtc->name, end_vbl, start_vbl); + spin_lock_irq(&crc->lock); crc->ctx_changed = true; spin_unlock_irq(&crc->lock);