Hi Am 24.06.21 um 10:06 schrieb Jani Nikula:
On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:For KMS drivers, replace the IRQ check in VBLANK ioctls with a check for vblank support. IRQs might be enabled wthout vblanking being supported. This change also removes the DRM framework's only dependency on IRQ state for non-legacy drivers. For legacy drivers with userspace modesetting, the original test remains in drm_wait_vblank_ioctl(). v3: * optimize test in drm_wait_vblank_ioctl() for KMS case (Liviu) * update docs for drm_irq_uninstall() v2: * keep the old test for legacy drivers in drm_wait_vblank_ioctl() (Daniel) Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx> --- drivers/gpu/drm/drm_irq.c | 13 ++++--------- drivers/gpu/drm/drm_vblank.c | 16 ++++++++++++---- 2 files changed, 16 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index c3bd664ea733..945dd82e2ea3 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -74,10 +74,8 @@ * only supports devices with a single interrupt on the main device stored in * &drm_device.dev and set as the device paramter in drm_dev_alloc(). * - * These IRQ helpers are strictly optional. Drivers which roll their own only - * need to set &drm_device.irq_enabled to signal the DRM core that vblank - * interrupts are working. Since these helpers don't automatically clean up the - * requested interrupt like e.g. devm_request_irq() they're not really + * These IRQ helpers are strictly optional. Since these helpers don't automatically + * clean up the requested interrupt like e.g. devm_request_irq() they're not really * recommended. */@@ -91,9 +89,7 @@* and after the installation. * * This is the simplified helper interface provided for drivers with no special - * needs. Drivers which need to install interrupt handlers for multiple - * interrupts must instead set &drm_device.irq_enabled to signal the DRM core - * that vblank interrupts are available. + * needs. * * @irq must match the interrupt number that would be passed to request_irq(), * if called directly instead of using this helper function. @@ -156,8 +152,7 @@ EXPORT_SYMBOL(drm_irq_install); * * Calls the driver's &drm_driver.irq_uninstall function and unregisters the IRQ * handler. This should only be called by drivers which used drm_irq_install() - * to set up their interrupt handler. Other drivers must only reset - * &drm_device.irq_enabled to false. + * to set up their interrupt handler. * * Note that for kernel modesetting drivers it is a bug if this function fails. * The sanity checks are only to catch buggy user modesetting drivers which call diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 3417e1ac7918..10fe16bafcb6 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -1748,8 +1748,16 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, unsigned int pipe_index; unsigned int flags, pipe, high_pipe;- if (!dev->irq_enabled)- return -EOPNOTSUPP; +#if defined(CONFIG_DRM_LEGACY) + if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) { + if (!dev->irq_enabled) + return -EOPNOTSUPP; + } else /* if DRIVER_MODESET */ +#endif + { + if (!drm_dev_has_vblank(dev)) + return -EOPNOTSUPP; + }Sheesh I hate this kind of inline #ifdefs. Two alternate suggestions that I believe should be as just efficient:
Or how about:
static bool drm_wait_vblank_supported(struct drm_device *dev)
{
if defined(CONFIG_DRM_LEGACY)
if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY)))
return dev->irq_enabled;
#endif
return drm_dev_has_vblank(dev);
}
?
It's inline, but still readable.
Best regards
Thomas
1) The more verbose: #if defined(CONFIG_DRM_LEGACY) static bool drm_wait_vblank_supported(struct drm_device *dev) { if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) return dev->irq_enabled; else return drm_dev_has_vblank(dev); } #else static bool drm_wait_vblank_supported(struct drm_device *dev) { return drm_dev_has_vblank(dev); } #endif 2) The more compact: static bool drm_wait_vblank_supported(struct drm_device *dev) { if (IS_ENABLED(CONFIG_DRM_LEGACY) && unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) return dev->irq_enabled; else return drm_dev_has_vblank(dev); } Then, in drm_wait_vblank_ioctl(). if (!drm_wait_vblank_supported(dev)) return -EOPNOTSUPP; The compiler should do the right thing without any explicit inline keywords etc. BR, Jani.if (vblwait->request.type & _DRM_VBLANK_SIGNAL)return -EINVAL; @@ -2023,7 +2031,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EOPNOTSUPP;- if (!dev->irq_enabled)+ if (!drm_dev_has_vblank(dev)) return -EOPNOTSUPP;crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id);@@ -2082,7 +2090,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EOPNOTSUPP;- if (!dev->irq_enabled)+ if (!drm_dev_has_vblank(dev)) return -EOPNOTSUPP;crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id);
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
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