| Message ID | 20210622141002.11590-1-tzimmermann@suse.de |
|---|---|
| Headers | show |
| Series | Deprecate struct drm_device.irq_enabled | expand |
Hello, On Tue, Jun 22, 2021 at 04:09:44PM +0200, Thomas Zimmermann 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(). > > v2: > * keep the old test for legacy drivers in > drm_wait_vblank_ioctl() (Daniel) > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > --- > drivers/gpu/drm/drm_irq.c | 10 +++------- > drivers/gpu/drm/drm_vblank.c | 13 +++++++++---- > 2 files changed, 12 insertions(+), 11 deletions(-) > > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c > index c3bd664ea733..1d7785721323 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. > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 3417e1ac7918..a98a4aad5037 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -1748,8 +1748,13 @@ 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 (drm_core_check_feature(dev, DRIVER_MODESET)) { > + if (!drm_dev_has_vblank(dev)) > + return -EOPNOTSUPP; > + } else { > + if (!dev->irq_enabled) > + return -EOPNOTSUPP; > + } For a system call that is used quite a lot by userspace we have increased the code size in a noticeable way. Can we not cache it privately? Best regards, Liviu > > if (vblwait->request.type & _DRM_VBLANK_SIGNAL) > return -EINVAL; > @@ -2023,7 +2028,7 @@ 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 +2087,7 @@ 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); > -- > 2.32.0 >
On Tue, Jun 22, 2021 at 04:09:46PM +0200, Thomas Zimmermann wrote: > The field drm_device.irq_enabled is only used by legacy drivers > with userspace modesetting. Don't set it in malidp. > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Acked-by: Liviu Dudau <liviu.dudau@arm.com> Best regards, Liviu > --- > drivers/gpu/drm/arm/malidp_drv.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c > index de59f3302516..78d15b04b105 100644 > --- a/drivers/gpu/drm/arm/malidp_drv.c > +++ b/drivers/gpu/drm/arm/malidp_drv.c > @@ -847,8 +847,6 @@ static int malidp_bind(struct device *dev) > if (ret < 0) > goto irq_init_fail; > > - drm->irq_enabled = true; > - > ret = drm_vblank_init(drm, drm->mode_config.num_crtc); > if (ret < 0) { > DRM_ERROR("failed to initialise vblank\n"); > @@ -874,7 +872,6 @@ static int malidp_bind(struct device *dev) > vblank_fail: > malidp_se_irq_fini(hwdev); > malidp_de_irq_fini(hwdev); > - drm->irq_enabled = false; > irq_init_fail: > drm_atomic_helper_shutdown(drm); > component_unbind_all(dev, drm); > @@ -909,7 +906,6 @@ static void malidp_unbind(struct device *dev) > drm_atomic_helper_shutdown(drm); > malidp_se_irq_fini(hwdev); > malidp_de_irq_fini(hwdev); > - drm->irq_enabled = false; > component_unbind_all(dev, drm); > of_node_put(malidp->crtc.port); > malidp->crtc.port = NULL; > -- > 2.32.0 >
On Tue, Jun 22, 2021 at 07:11:33PM +0300, Laurent Pinchart wrote: > Hi Thomas, > > Thank you for the patches. > > On Tue, Jun 22, 2021 at 04:09:40PM +0200, Thomas Zimmermann wrote: > > Remove references to struct drm_device.irq_enabled from modern > > DRM drivers and core. > > > > KMS drivers enable IRQs for their devices internally. They don't > > have to keep track of the IRQ state via irq_enabled. For vblanking, > > it's cleaner to test for vblanking support directly than to test > > for enabled IRQs. > > > > This used to be a single patch, [1] but it's now a full series. > > > > The first 3 patches replace instances of irq_enabled that are not > > required. > > > > Patch 4 fixes vblank ioctls to actually test for vblank support > > instead of IRQs. > > > > THe rest of the patchset removes irq_enabled from all non-legacy > > drivers. The only exception is omapdrm, which has an internal > > dpendency on the field's value. For this drivers, the state gets > > duplicated internally. > > > > With the patchset applied, drivers can later switch over to plain > > Linux IRQ interfaces and DRM's IRQ midlayer can be declared legacy. > > > > v2: > > * keep the original test for legacy drivers in > > drm_wait_vblank_ioctl() (Daniel) > > > > [1] https://lore.kernel.org/dri-devel/20210608090301.4752-1-tzimmermann@suse.de/ > > > > Thomas Zimmermann (22): > > drm/amdgpu: Track IRQ state in local device state > > drm/hibmc: Call drm_irq_uninstall() unconditionally > > drm/radeon: Track IRQ state in local device state > > drm: Don't test for IRQ support in VBLANK ioctls > > drm/komeda: Don't set struct drm_device.irq_enabled > > drm/malidp: Don't set struct drm_device.irq_enabled > > drm/exynos: Don't set struct drm_device.irq_enabled > > drm/kirin: Don't set struct drm_device.irq_enabled > > drm/imx: Don't set struct drm_device.irq_enabled > > drm/mediatek: Don't set struct drm_device.irq_enabled > > drm/nouveau: Don't set struct drm_device.irq_enabled > > drm/omapdrm: Track IRQ state in local device state > > drm/rockchip: Don't set struct drm_device.irq_enabled > > drm/sti: Don't set struct drm_device.irq_enabled > > drm/stm: Don't set struct drm_device.irq_enabled > > drm/sun4i: Don't set struct drm_device.irq_enabled > > drm/tegra: Don't set struct drm_device.irq_enabled > > drm/tidss: Don't use struct drm_device.irq_enabled > > drm/vc4: Don't set struct drm_device.irq_enabled > > drm/vmwgfx: Don't set struct drm_device.irq_enabled > > drm/xlnx: Don't set struct drm_device.irq_enabled > > drm/zte: Don't set struct drm_device.irq_enabled > > The list seems to be missing armada, rcar-du and vkms. It would also be > nice to address i915 if possible. In addition to this, for all the existing patches, Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > > drivers/gpu/drm/amd/amdgpu/amdgpu_irq.c | 6 +++--- > > drivers/gpu/drm/arm/display/komeda/komeda_kms.c | 4 ---- > > drivers/gpu/drm/arm/malidp_drv.c | 4 ---- > > drivers/gpu/drm/drm_irq.c | 10 +++------- > > drivers/gpu/drm/drm_vblank.c | 13 +++++++++---- > > drivers/gpu/drm/exynos/exynos_drm_drv.c | 10 ---------- > > drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 3 +-- > > drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c | 2 -- > > drivers/gpu/drm/imx/dcss/dcss-kms.c | 3 --- > > drivers/gpu/drm/imx/imx-drm-core.c | 11 ----------- > > drivers/gpu/drm/mediatek/mtk_drm_drv.c | 6 ------ > > drivers/gpu/drm/nouveau/nouveau_drm.c | 3 --- > > drivers/gpu/drm/omapdrm/omap_drv.h | 2 ++ > > drivers/gpu/drm/omapdrm/omap_irq.c | 6 +++--- > > drivers/gpu/drm/radeon/radeon_fence.c | 2 +- > > drivers/gpu/drm/radeon/radeon_irq_kms.c | 16 ++++++++-------- > > drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 6 ------ > > drivers/gpu/drm/sti/sti_compositor.c | 2 -- > > drivers/gpu/drm/stm/ltdc.c | 3 --- > > drivers/gpu/drm/sun4i/sun4i_drv.c | 2 -- > > drivers/gpu/drm/tegra/drm.c | 7 ------- > > drivers/gpu/drm/tidss/tidss_irq.c | 3 --- > > drivers/gpu/drm/vc4/vc4_kms.c | 1 - > > drivers/gpu/drm/vmwgfx/vmwgfx_irq.c | 8 -------- > > drivers/gpu/drm/xlnx/zynqmp_dpsub.c | 2 -- > > drivers/gpu/drm/zte/zx_drm_drv.c | 6 ------ > > 26 files changed, 30 insertions(+), 111 deletions(-) > > > > > > base-commit: 8c1323b422f8473421682ba783b5949ddd89a3f4 > > prerequisite-patch-id: c2b2f08f0eccc9f5df0c0da49fa1d36267deb11d > > prerequisite-patch-id: c67e5d886a47b7d0266d81100837557fda34cb24
Hi Liviu Am 22.06.21 um 17:25 schrieb Liviu Dudau: > Hello, > > On Tue, Jun 22, 2021 at 04:09:44PM +0200, Thomas Zimmermann 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(). >> >> v2: >> * keep the old test for legacy drivers in >> drm_wait_vblank_ioctl() (Daniel) >> >> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> >> --- >> drivers/gpu/drm/drm_irq.c | 10 +++------- >> drivers/gpu/drm/drm_vblank.c | 13 +++++++++---- >> 2 files changed, 12 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c >> index c3bd664ea733..1d7785721323 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. >> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c >> index 3417e1ac7918..a98a4aad5037 100644 >> --- a/drivers/gpu/drm/drm_vblank.c >> +++ b/drivers/gpu/drm/drm_vblank.c >> @@ -1748,8 +1748,13 @@ 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 (drm_core_check_feature(dev, DRIVER_MODESET)) { >> + if (!drm_dev_has_vblank(dev)) >> + return -EOPNOTSUPP; >> + } else { >> + if (!dev->irq_enabled) >> + return -EOPNOTSUPP; >> + } > > For a system call that is used quite a lot by userspace we have increased the code size > in a noticeable way. Can we not cache it privately? I'm not quite sure that I understand your concern. The additionally called functions are trivial one-liners; probably inlined anyway. However, irq_enabled is only relevant for legacy drivers and will eventually disappear behind CONFIG_DRM_LEGACY. We can rewrite the test like this: ifdef CONFIG_DRM_LEGACY if (unlikely(check_feature(dev, DRIVER_LEGACY))) { if (!irq_enabled) return; } else #endif { if (!has_vblank_support(dev)) return; } As CONFIG_DRM_LEGACY is most likely disabled on concurrent systems, we'd get a single test for the modern drivers. If DRM_LEGACYis on, the compiler at least knows that the else branch is preferred. Best regards Thomas -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
Am 22.06.21 um 18:11 schrieb Laurent Pinchart: > Hi Thomas, > > Thank you for the patches. > > On Tue, Jun 22, 2021 at 04:09:40PM +0200, Thomas Zimmermann wrote: >> Remove references to struct drm_device.irq_enabled from modern >> DRM drivers and core. >> >> KMS drivers enable IRQs for their devices internally. They don't >> have to keep track of the IRQ state via irq_enabled. For vblanking, >> it's cleaner to test for vblanking support directly than to test >> for enabled IRQs. >> >> This used to be a single patch, [1] but it's now a full series. >> >> The first 3 patches replace instances of irq_enabled that are not >> required. >> >> Patch 4 fixes vblank ioctls to actually test for vblank support >> instead of IRQs. >> >> THe rest of the patchset removes irq_enabled from all non-legacy >> drivers. The only exception is omapdrm, which has an internal >> dpendency on the field's value. For this drivers, the state gets >> duplicated internally. >> >> With the patchset applied, drivers can later switch over to plain >> Linux IRQ interfaces and DRM's IRQ midlayer can be declared legacy. >> >> v2: >> * keep the original test for legacy drivers in >> drm_wait_vblank_ioctl() (Daniel) >> >> [1] https://lore.kernel.org/dri-devel/20210608090301.4752-1-tzimmermann@suse.de/ >> >> Thomas Zimmermann (22): >> drm/amdgpu: Track IRQ state in local device state >> drm/hibmc: Call drm_irq_uninstall() unconditionally >> drm/radeon: Track IRQ state in local device state >> drm: Don't test for IRQ support in VBLANK ioctls >> drm/komeda: Don't set struct drm_device.irq_enabled >> drm/malidp: Don't set struct drm_device.irq_enabled >> drm/exynos: Don't set struct drm_device.irq_enabled >> drm/kirin: Don't set struct drm_device.irq_enabled >> drm/imx: Don't set struct drm_device.irq_enabled >> drm/mediatek: Don't set struct drm_device.irq_enabled >> drm/nouveau: Don't set struct drm_device.irq_enabled >> drm/omapdrm: Track IRQ state in local device state >> drm/rockchip: Don't set struct drm_device.irq_enabled >> drm/sti: Don't set struct drm_device.irq_enabled >> drm/stm: Don't set struct drm_device.irq_enabled >> drm/sun4i: Don't set struct drm_device.irq_enabled >> drm/tegra: Don't set struct drm_device.irq_enabled >> drm/tidss: Don't use struct drm_device.irq_enabled >> drm/vc4: Don't set struct drm_device.irq_enabled >> drm/vmwgfx: Don't set struct drm_device.irq_enabled >> drm/xlnx: Don't set struct drm_device.irq_enabled >> drm/zte: Don't set struct drm_device.irq_enabled > > The list seems to be missing armada, rcar-du and vkms. It would also be > nice to address i915 if possible. Indeed. I grepped for \>irq_enabled. But some few drivers use .irq_enabled. I'll fix this in the patchset's next iteration. Thanks for double checking. Best regards Thomas
Hi Thomas, On Wed, Jun 23, 2021 at 08:43:07AM +0200, Thomas Zimmermann wrote: > Hi Liviu > > Am 22.06.21 um 17:25 schrieb Liviu Dudau: > > Hello, > > > > On Tue, Jun 22, 2021 at 04:09:44PM +0200, Thomas Zimmermann 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(). > > > > > > v2: > > > * keep the old test for legacy drivers in > > > drm_wait_vblank_ioctl() (Daniel) > > > > > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > > > --- > > > drivers/gpu/drm/drm_irq.c | 10 +++------- > > > drivers/gpu/drm/drm_vblank.c | 13 +++++++++---- > > > 2 files changed, 12 insertions(+), 11 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c > > > index c3bd664ea733..1d7785721323 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. > > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > > > index 3417e1ac7918..a98a4aad5037 100644 > > > --- a/drivers/gpu/drm/drm_vblank.c > > > +++ b/drivers/gpu/drm/drm_vblank.c > > > @@ -1748,8 +1748,13 @@ 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 (drm_core_check_feature(dev, DRIVER_MODESET)) { > > > + if (!drm_dev_has_vblank(dev)) > > > + return -EOPNOTSUPP; > > > + } else { > > > + if (!dev->irq_enabled) > > > + return -EOPNOTSUPP; > > > + } > > > > For a system call that is used quite a lot by userspace we have increased the code size > > in a noticeable way. Can we not cache it privately? > > I'm not quite sure that I understand your concern. The additionally called > functions are trivial one-liners; probably inlined anyway. They are inlined. However we replace the pointer dereference (which can be calculated at compile time as offset from a base pointer) with the code in drm_core_check_all_features() that does 3 pointer dereferences, masking and logical AND before checking for matching value. > > However, irq_enabled is only relevant for legacy drivers and will eventually > disappear behind CONFIG_DRM_LEGACY. We can rewrite the test like this: I get the point that irq_enabled is legacy. However the IOCTL call is not and usually is used in time critical code to wait for vblank before starting the old buffers for a new frame. At 60Hz that's probably less of a concern, but at 120Hz refresh rate and reduced vblank time your time slice allocation for new work matters. Best regards, Liviu > > ifdef CONFIG_DRM_LEGACY > if (unlikely(check_feature(dev, DRIVER_LEGACY))) { > if (!irq_enabled) > return; > } else > #endif > { > if (!has_vblank_support(dev)) > return; > } > > As CONFIG_DRM_LEGACY is most likely disabled on concurrent systems, we'd get > a single test for the modern drivers. If DRM_LEGACYis on, the compiler at > least knows that the else branch is preferred. > > Best regards > Thomas > > -- > Thomas Zimmermann > Graphics Driver Developer > SUSE Software Solutions Germany GmbH > Maxfeldstr. 5, 90409 Nürnberg, Germany > (HRB 36809, AG Nürnberg) > Geschäftsführer: Felix Imendörffer >