| Message ID | 20200115121652.7050-3-tzimmermann@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: Clean up VBLANK callbacks in struct drm_driver | expand |
On Wed, Jan 15, 2020 at 01:16:33PM +0100, Thomas Zimmermann wrote: > VBLANK interrupts can be disabled immediately or with a delay, where the > latter is the default. The former option can be selected by setting > get_vblank_timestamp, and enabling vblank_disable_immediate in struct > drm_device. > > The setup is only evaluated once when DRM initializes VBLANKs. Evaluating > the settings on each use of vblank_disable_immediate will allow for easy > integration of CRTC VBLANK functions. > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > --- > drivers/gpu/drm/drm_vblank.c | 31 ++++++++++++++----------------- > 1 file changed, 14 insertions(+), 17 deletions(-) > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 3f1dd54cc8bb..abb085c67d82 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -481,19 +481,6 @@ int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) > > DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); > > - /* Driver specific high-precision vblank timestamping supported? */ > - if (dev->driver->get_vblank_timestamp) > - DRM_INFO("Driver supports precise vblank timestamp query.\n"); > - else > - DRM_INFO("No driver support for vblank timestamp query.\n"); > - > - /* Must have precise timestamping for reliable vblank instant disable */ > - if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { > - dev->vblank_disable_immediate = false; > - DRM_INFO("Setting vblank_disable_immediate to false because " > - "get_vblank_timestamp == NULL\n"); > - } Which drivers are so broken they set vblank_disable_immediate to true without having the vfunc specified? IMO this code should just go away (or converted to a WARN). > - > return 0; > > err: > @@ -1070,6 +1057,15 @@ int drm_crtc_vblank_get(struct drm_crtc *crtc) > } > EXPORT_SYMBOL(drm_crtc_vblank_get); > > +static bool __vblank_disable_immediate(struct drm_device *dev, unsigned int pipe) > +{ > + if (!dev->vblank_disable_immediate) > + return false; > + if (!dev->driver->get_vblank_timestamp) > + return false; > + return true; > +} > + > static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) > { > struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; > @@ -1086,7 +1082,7 @@ static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) > return; > else if (drm_vblank_offdelay < 0) > vblank_disable_fn(&vblank->disable_timer); > - else if (!dev->vblank_disable_immediate) > + else if (__vblank_disable_immediate(dev, pipe)) > mod_timer(&vblank->disable_timer, > jiffies + ((drm_vblank_offdelay * HZ)/1000)); > } > @@ -1663,7 +1659,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, > /* If the counter is currently enabled and accurate, short-circuit > * queries to return the cached timestamp of the last vblank. > */ > - if (dev->vblank_disable_immediate && > + if (__vblank_disable_immediate(dev, pipe) && > drm_wait_vblank_is_query(vblwait) && > READ_ONCE(vblank->enabled)) { > drm_wait_vblank_reply(dev, pipe, &vblwait->reply); > @@ -1820,7 +1816,7 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) > * been signaled. The disable has to be last (after > * drm_handle_vblank_events) so that the timestamp is always accurate. > */ > - disable_irq = (dev->vblank_disable_immediate && > + disable_irq = (__vblank_disable_immediate(dev, pipe) && > drm_vblank_offdelay > 0 && > !atomic_read(&vblank->refcount)); > > @@ -1893,7 +1889,8 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, > pipe = drm_crtc_index(crtc); > > vblank = &dev->vblank[pipe]; > - vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled); > + vblank_enabled = __vblank_disable_immediate(dev, pipe) && > + READ_ONCE(vblank->enabled); > > if (!vblank_enabled) { > ret = drm_crtc_vblank_get(crtc); > -- > 2.24.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Hi Am 15.01.20 um 15:37 schrieb Ville Syrjälä: > On Wed, Jan 15, 2020 at 01:16:33PM +0100, Thomas Zimmermann wrote: >> VBLANK interrupts can be disabled immediately or with a delay, where the >> latter is the default. The former option can be selected by setting >> get_vblank_timestamp, and enabling vblank_disable_immediate in struct >> drm_device. >> >> The setup is only evaluated once when DRM initializes VBLANKs. Evaluating >> the settings on each use of vblank_disable_immediate will allow for easy >> integration of CRTC VBLANK functions. >> >> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> >> --- >> drivers/gpu/drm/drm_vblank.c | 31 ++++++++++++++----------------- >> 1 file changed, 14 insertions(+), 17 deletions(-) >> >> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c >> index 3f1dd54cc8bb..abb085c67d82 100644 >> --- a/drivers/gpu/drm/drm_vblank.c >> +++ b/drivers/gpu/drm/drm_vblank.c >> @@ -481,19 +481,6 @@ int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) >> >> DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); >> >> - /* Driver specific high-precision vblank timestamping supported? */ >> - if (dev->driver->get_vblank_timestamp) >> - DRM_INFO("Driver supports precise vblank timestamp query.\n"); >> - else >> - DRM_INFO("No driver support for vblank timestamp query.\n"); >> - >> - /* Must have precise timestamping for reliable vblank instant disable */ >> - if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { >> - dev->vblank_disable_immediate = false; >> - DRM_INFO("Setting vblank_disable_immediate to false because " >> - "get_vblank_timestamp == NULL\n"); >> - } > > Which drivers are so broken they set vblank_disable_immediate to true > without having the vfunc specified? IMO this code should just go away > (or converted to a WARN). It's probably not a problem in practice. I'll put WARN_ON around the condition. Best regards Thomas > >> - >> return 0; >> >> err: >> @@ -1070,6 +1057,15 @@ int drm_crtc_vblank_get(struct drm_crtc *crtc) >> } >> EXPORT_SYMBOL(drm_crtc_vblank_get); >> >> +static bool __vblank_disable_immediate(struct drm_device *dev, unsigned int pipe) >> +{ >> + if (!dev->vblank_disable_immediate) >> + return false; >> + if (!dev->driver->get_vblank_timestamp) >> + return false; >> + return true; >> +} >> + >> static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) >> { >> struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; >> @@ -1086,7 +1082,7 @@ static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) >> return; >> else if (drm_vblank_offdelay < 0) >> vblank_disable_fn(&vblank->disable_timer); >> - else if (!dev->vblank_disable_immediate) >> + else if (__vblank_disable_immediate(dev, pipe)) >> mod_timer(&vblank->disable_timer, >> jiffies + ((drm_vblank_offdelay * HZ)/1000)); >> } >> @@ -1663,7 +1659,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, >> /* If the counter is currently enabled and accurate, short-circuit >> * queries to return the cached timestamp of the last vblank. >> */ >> - if (dev->vblank_disable_immediate && >> + if (__vblank_disable_immediate(dev, pipe) && >> drm_wait_vblank_is_query(vblwait) && >> READ_ONCE(vblank->enabled)) { >> drm_wait_vblank_reply(dev, pipe, &vblwait->reply); >> @@ -1820,7 +1816,7 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) >> * been signaled. The disable has to be last (after >> * drm_handle_vblank_events) so that the timestamp is always accurate. >> */ >> - disable_irq = (dev->vblank_disable_immediate && >> + disable_irq = (__vblank_disable_immediate(dev, pipe) && >> drm_vblank_offdelay > 0 && >> !atomic_read(&vblank->refcount)); >> >> @@ -1893,7 +1889,8 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, >> pipe = drm_crtc_index(crtc); >> >> vblank = &dev->vblank[pipe]; >> - vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled); >> + vblank_enabled = __vblank_disable_immediate(dev, pipe) && >> + READ_ONCE(vblank->enabled); >> >> if (!vblank_enabled) { >> ret = drm_crtc_vblank_get(crtc); >> -- >> 2.24.1 >> >> _______________________________________________ >> Intel-gfx mailing list >> Intel-gfx@lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx >
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 3f1dd54cc8bb..abb085c67d82 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -481,19 +481,6 @@ int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); - /* Driver specific high-precision vblank timestamping supported? */ - if (dev->driver->get_vblank_timestamp) - DRM_INFO("Driver supports precise vblank timestamp query.\n"); - else - DRM_INFO("No driver support for vblank timestamp query.\n"); - - /* Must have precise timestamping for reliable vblank instant disable */ - if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { - dev->vblank_disable_immediate = false; - DRM_INFO("Setting vblank_disable_immediate to false because " - "get_vblank_timestamp == NULL\n"); - } - return 0; err: @@ -1070,6 +1057,15 @@ int drm_crtc_vblank_get(struct drm_crtc *crtc) } EXPORT_SYMBOL(drm_crtc_vblank_get); +static bool __vblank_disable_immediate(struct drm_device *dev, unsigned int pipe) +{ + if (!dev->vblank_disable_immediate) + return false; + if (!dev->driver->get_vblank_timestamp) + return false; + return true; +} + static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) { struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; @@ -1086,7 +1082,7 @@ static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) return; else if (drm_vblank_offdelay < 0) vblank_disable_fn(&vblank->disable_timer); - else if (!dev->vblank_disable_immediate) + else if (__vblank_disable_immediate(dev, pipe)) mod_timer(&vblank->disable_timer, jiffies + ((drm_vblank_offdelay * HZ)/1000)); } @@ -1663,7 +1659,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, /* If the counter is currently enabled and accurate, short-circuit * queries to return the cached timestamp of the last vblank. */ - if (dev->vblank_disable_immediate && + if (__vblank_disable_immediate(dev, pipe) && drm_wait_vblank_is_query(vblwait) && READ_ONCE(vblank->enabled)) { drm_wait_vblank_reply(dev, pipe, &vblwait->reply); @@ -1820,7 +1816,7 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) * been signaled. The disable has to be last (after * drm_handle_vblank_events) so that the timestamp is always accurate. */ - disable_irq = (dev->vblank_disable_immediate && + disable_irq = (__vblank_disable_immediate(dev, pipe) && drm_vblank_offdelay > 0 && !atomic_read(&vblank->refcount)); @@ -1893,7 +1889,8 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, pipe = drm_crtc_index(crtc); vblank = &dev->vblank[pipe]; - vblank_enabled = dev->vblank_disable_immediate && READ_ONCE(vblank->enabled); + vblank_enabled = __vblank_disable_immediate(dev, pipe) && + READ_ONCE(vblank->enabled); if (!vblank_enabled) { ret = drm_crtc_vblank_get(crtc);
VBLANK interrupts can be disabled immediately or with a delay, where the latter is the default. The former option can be selected by setting get_vblank_timestamp, and enabling vblank_disable_immediate in struct drm_device. The setup is only evaluated once when DRM initializes VBLANKs. Evaluating the settings on each use of vblank_disable_immediate will allow for easy integration of CRTC VBLANK functions. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> --- drivers/gpu/drm/drm_vblank.c | 31 ++++++++++++++----------------- 1 file changed, 14 insertions(+), 17 deletions(-)