| Message ID | 1461576105-3204-1-git-send-email-maarten.lankhorst@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Apr 25, 2016 at 11:21 AM, Maarten Lankhorst <maarten.lankhorst@linux.intel.com> wrote: > async_page_flip is a unrelated flag and should not be used for > testing support. It's up to the drivers to fail if they don't > support async commit. > > Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Once more (summary of our irc discussion): - DRM_MODE_PAGE_FLIP_ASYNC = flipping with tearing, i.e. not vblank synced. Gives you lower latency and unrestricted rendering, aka benchmark mode. Needs special hw support and on intel only supported on the primary plane. I think a better way to almost get all the benefits of async by simply implementing a queue of flips that all get collapsed to the next vblank. - async atomic commit = non-blocking ioctl. Two entirely orthogonal things (you could do blocking atomic commit with async flip, but doesn't make much sense). Maybe instead we need a better documentation for the FLIP_ASYNC flag? -Daniel > --- > drivers/gpu/drm/drm_atomic.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 984567057688..af8957b60388 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -1587,10 +1587,6 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > if (arg->reserved) > return -EINVAL; > > - if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) && > - !dev->mode_config.async_page_flip) > - return -EINVAL; > - > /* can't test and expect an event at the same time. */ > if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) && > (arg->flags & DRM_MODE_PAGE_FLIP_EVENT)) > -- > 2.1.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
Op 25-04-16 om 11:35 schreef Daniel Vetter: > On Mon, Apr 25, 2016 at 11:21 AM, Maarten Lankhorst > <maarten.lankhorst@linux.intel.com> wrote: >> async_page_flip is a unrelated flag and should not be used for >> testing support. It's up to the drivers to fail if they don't >> support async commit. >> >> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> > Once more (summary of our irc discussion): > > - DRM_MODE_PAGE_FLIP_ASYNC = flipping with tearing, i.e. not vblank > synced. Gives you lower latency and unrestricted rendering, aka > benchmark mode. Needs special hw support and on intel only supported > on the primary plane. I think a better way to almost get all the > benefits of async by simply implementing a queue of flips that all get > collapsed to the next vblank. > > - async atomic commit = non-blocking ioctl. > > Two entirely orthogonal things (you could do blocking atomic commit > with async flip, but doesn't make much sense). > > Maybe instead we need a better documentation for the FLIP_ASYNC flag? > yeah it's confusing, especially with atomic async commit. Maybe rename to nonblocking commit? ~Maarten
On Mon, Apr 25, 2016 at 11:37 AM, Maarten Lankhorst <maarten.lankhorst@linux.intel.com> wrote: > Op 25-04-16 om 11:35 schreef Daniel Vetter: >> On Mon, Apr 25, 2016 at 11:21 AM, Maarten Lankhorst >> <maarten.lankhorst@linux.intel.com> wrote: >>> async_page_flip is a unrelated flag and should not be used for >>> testing support. It's up to the drivers to fail if they don't >>> support async commit. >>> >>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> >> Once more (summary of our irc discussion): >> >> - DRM_MODE_PAGE_FLIP_ASYNC = flipping with tearing, i.e. not vblank >> synced. Gives you lower latency and unrestricted rendering, aka >> benchmark mode. Needs special hw support and on intel only supported >> on the primary plane. I think a better way to almost get all the >> benefits of async by simply implementing a queue of flips that all get >> collapsed to the next vblank. >> >> - async atomic commit = non-blocking ioctl. >> >> Two entirely orthogonal things (you could do blocking atomic commit >> with async flip, but doesn't make much sense). >> >> Maybe instead we need a better documentation for the FLIP_ASYNC flag? >> > yeah it's confusing, especially with atomic async commit. Maybe rename to nonblocking commit? Well uabi renaming train left the station, but internally we can definitely do that. s/drm_atomic_async_commit/drm_atomic_nonblocking_commit/ plus s/async/nonblocking/ in the driver's ->atomic_commit hooks sounds like a very fine idea. Volunteered? -Daniel
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 984567057688..af8957b60388 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1587,10 +1587,6 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, if (arg->reserved) return -EINVAL; - if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) && - !dev->mode_config.async_page_flip) - return -EINVAL; - /* can't test and expect an event at the same time. */ if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) && (arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
async_page_flip is a unrelated flag and should not be used for testing support. It's up to the drivers to fail if they don't support async commit. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> --- drivers/gpu/drm/drm_atomic.c | 4 ---- 1 file changed, 4 deletions(-)