On Mon, Jul 16, 2018 at 02:22:56PM -0400, Sean Paul wrote: > On Sat, Jul 14, 2018 at 03:23:32PM +0300, Haneen Mohammed wrote: > > Implement the set_crc_source() callback. > > Compute CRC using crc32 on the visible part of the framebuffer. > > Use ordered workqueue to compute and add CRC at the end of a vblank. > > > > Use appropriate synchronization methods since the crc computation must > > be atomic wrt the generated vblank event for a given atomic update, > > > > Signed-off-by: Haneen Mohammed <hamohammed.sa@xxxxxxxxx> > > Hey Haneen, > Thanks for revising this patch set. Things are looking good across the series, > just a few more comments :-) > Thank you so much for the review! > > --- > > Changes in v2: > > - Include this patch in this patchset. > > > > drivers/gpu/drm/vkms/Makefile | 2 +- > > drivers/gpu/drm/vkms/vkms_crtc.c | 60 ++++++++++++++++++++++++++----- > > drivers/gpu/drm/vkms/vkms_drv.c | 1 + > > drivers/gpu/drm/vkms/vkms_drv.h | 21 +++++++++++ > > drivers/gpu/drm/vkms/vkms_plane.c | 10 ++++++ > > 5 files changed, 85 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile > > index 986297da51bf..37966914f70b 100644 > > --- a/drivers/gpu/drm/vkms/Makefile > > +++ b/drivers/gpu/drm/vkms/Makefile > > @@ -1,3 +1,3 @@ > > -vkms-y := vkms_drv.o vkms_plane.o vkms_output.o vkms_crtc.o vkms_gem.o > > +vkms-y := vkms_drv.o vkms_plane.o vkms_output.o vkms_crtc.o vkms_gem.o vkms_crc.o > > > > obj-$(CONFIG_DRM_VKMS) += vkms.o > > diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c > > index 26babb85ca77..f3a674db33b8 100644 > > --- a/drivers/gpu/drm/vkms/vkms_crtc.c > > +++ b/drivers/gpu/drm/vkms/vkms_crtc.c > > @@ -10,18 +10,36 @@ > > #include <drm/drm_atomic_helper.h> > > #include <drm/drm_crtc_helper.h> > > > > -static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer) > > +static void _vblank_handle(struct vkms_output *output) > > { > > - struct vkms_output *output = container_of(timer, struct vkms_output, > > - vblank_hrtimer); > > struct drm_crtc *crtc = &output->crtc; > > - int ret_overrun; > > + struct vkms_crtc_state *state = to_vkms_crtc_state(crtc->state); > > bool ret; > > > > + int crc_enabled = 0; > > + > > + spin_lock(&output->lock); > > + crc_enabled = output->crc_enabled; > > Aside from the implicit bool -> int cast, I don't think you need this local var, > just use output->crc_enabled directly below. > > > ret = drm_crtc_handle_vblank(crtc); > > if (!ret) > > DRM_ERROR("vkms failure on handling vblank"); > > This would be more useful with the error code printed. > I think this only returns false on failure. Also I've noticed most of the usage of drm_crtc_handle_vblank don't check the return value, should I do the same as well and drop ret and error message? > > > > + if (state && crc_enabled) { > > + state->n_frame = drm_crtc_accurate_vblank_count(crtc); > > + queue_work(output->crc_workq, &state->crc_work); > > + } > > + > > + spin_unlock(&output->lock); > > +} > > + > > +static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer) > > +{ > > + struct vkms_output *output = container_of(timer, struct vkms_output, > > + vblank_hrtimer); > > + int ret_overrun; > > + > > + _vblank_handle(output); > > + > > ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer, > > output->period_ns); > > > > @@ -97,6 +115,8 @@ vkms_atomic_crtc_duplicate_state(struct drm_crtc *crtc) > > > > __drm_atomic_helper_crtc_duplicate_state(crtc, &vkms_state->base); > > > > + INIT_WORK(&vkms_state->crc_work, vkms_crc_work_handle); > > + > > return &vkms_state->base; > > } > > > > @@ -104,11 +124,18 @@ static void vkms_atomic_crtc_destroy_state(struct drm_crtc *crtc, > > struct drm_crtc_state *state) > > { > > struct vkms_crtc_state *vkms_state; > > + struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc); > > > > vkms_state = to_vkms_crtc_state(state); > > > > __drm_atomic_helper_crtc_destroy_state(state); > > - kfree(vkms_state); > > + > > + if (vkms_state) { > > + flush_workqueue(vkms_out->crc_workq); > > I'm a little worried about this bit. Since the workqueue is per-output, is it > possible you'll be waiting for more frames to complete than you need to be? > I see, maybe I should flush per work_struct instead? > > + drm_framebuffer_put(&vkms_state->data.fb); > > + memset(&vkms_state->data, 0, sizeof(struct vkms_crc_data)); > > + kfree(vkms_state); > > + } > > } > > > > static const struct drm_crtc_funcs vkms_crtc_funcs = { > > @@ -120,6 +147,7 @@ static const struct drm_crtc_funcs vkms_crtc_funcs = { > > .atomic_destroy_state = vkms_atomic_crtc_destroy_state, > > .enable_vblank = vkms_enable_vblank, > > .disable_vblank = vkms_disable_vblank, > > + .set_crc_source = vkms_set_crc_source, > > }; > > > > static void vkms_crtc_atomic_enable(struct drm_crtc *crtc, > > @@ -134,26 +162,37 @@ static void vkms_crtc_atomic_disable(struct drm_crtc *crtc, > > drm_crtc_vblank_off(crtc); > > } > > > > +static void vkms_crtc_atomic_begin(struct drm_crtc *crtc, > > + struct drm_crtc_state *old_crtc_state) > > +{ > > + struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc); > > + > > + spin_lock_irq(&vkms_output->lock); > > Hmm, you can't lock across atomic_begin/flush. What is this protecting against? > I did this per Daniel recommendation: 1- spin_lock_irq -> vkms_crtc_atomic_begin 2- update vkms_crc_data and get ref to fb -> vkms_primary_plane_update 3- spin_unlock_irq after vblank event -> vkms_crtc_atomic_flush > > +} > > + > > static void vkms_crtc_atomic_flush(struct drm_crtc *crtc, > > struct drm_crtc_state *old_crtc_state) > > { > > - unsigned long flags; > > + struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc); > > > > if (crtc->state->event) { > > - spin_lock_irqsave(&crtc->dev->event_lock, flags); > > + spin_lock(&crtc->dev->event_lock); > > What's the rationale behind this change? > hm I am not sure if this is correct, but I assume because spin_lock_irq in atomic_begin would disable interrupts and since this is before we unlock vkms_output->lock with spin_unlock_irq so irqsave here is not necessary? > > > > if (drm_crtc_vblank_get(crtc) != 0) > > drm_crtc_send_vblank_event(crtc, crtc->state->event); > > else > > drm_crtc_arm_vblank_event(crtc, crtc->state->event); > > > > - spin_unlock_irqrestore(&crtc->dev->event_lock, flags); > > + spin_unlock(&crtc->dev->event_lock); > > > > crtc->state->event = NULL; > > } > > + > > + spin_unlock_irq(&vkms_output->lock); > > } > > > > static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = { > > + .atomic_begin = vkms_crtc_atomic_begin, > > .atomic_flush = vkms_crtc_atomic_flush, > > .atomic_enable = vkms_crtc_atomic_enable, > > .atomic_disable = vkms_crtc_atomic_disable, > > @@ -162,6 +201,7 @@ static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = { > > int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc, > > struct drm_plane *primary, struct drm_plane *cursor) > > { > > + struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc); > > int ret; > > > > ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor, > > @@ -173,5 +213,9 @@ int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc, > > > > drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs); > > > > + spin_lock_init(&vkms_out->lock); > > + > > + vkms_out->crc_workq = alloc_ordered_workqueue("vkms_crc_workq", 0); > > + > > return ret; > > } > > diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c > > index 37aa2ef33b21..5d78bd97e69c 100644 > > --- a/drivers/gpu/drm/vkms/vkms_drv.c > > +++ b/drivers/gpu/drm/vkms/vkms_drv.c > > @@ -46,6 +46,7 @@ static void vkms_release(struct drm_device *dev) > > platform_device_unregister(vkms->platform); > > drm_mode_config_cleanup(&vkms->drm); > > drm_dev_fini(&vkms->drm); > > + destroy_workqueue(vkms->output.crc_workq); > > } > > > > static struct drm_driver vkms_driver = { > > diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h > > index bf811d0ec349..95985649768c 100644 > > --- a/drivers/gpu/drm/vkms/vkms_drv.h > > +++ b/drivers/gpu/drm/vkms/vkms_drv.h > > @@ -20,12 +20,23 @@ static const u32 vkms_formats[] = { > > DRM_FORMAT_XRGB8888, > > }; > > > > +struct vkms_crc_data { > > + struct drm_rect src; > > + struct drm_framebuffer fb; > > +}; > > + > > /** > > * vkms_crtc_state - Driver specific CRTC state > > * @base: base CRTC state > > + * @crc_work: work struct to compute and add CRC entries > > + * @data: data required for CRC computation > > + * @n_frame: frame number for computed CRC > > */ > > struct vkms_crtc_state { > > struct drm_crtc_state base; > > + struct work_struct crc_work; > > + struct vkms_crc_data data; > > + unsigned int n_frame; > > }; > > > > struct vkms_output { > > @@ -35,6 +46,11 @@ struct vkms_output { > > struct hrtimer vblank_hrtimer; > > ktime_t period_ns; > > struct drm_pending_vblank_event *event; > > + bool crc_enabled; > > Where is this set to true? > Oh sorry I forgot to add a vkms_crc.c which sets crc_enabled in set_crc_source callback! I'll work on fixing the issues you mentioned here and the other patches as well, thank you so much again! Haneen > > + /* ordered wq for crc_work */ > > + struct workqueue_struct *crc_workq; > > + /* protects concurrent access to crc_data */ > > + spinlock_t lock; > > }; > > > > struct vkms_device { > > @@ -95,4 +111,9 @@ void *vkms_gem_vmap(struct drm_gem_object *obj); > > > > void vkms_gem_vunmap(struct drm_gem_object *obj); > > > > +/* CRC Support */ > > +int vkms_set_crc_source(struct drm_crtc *crtc, const char *src_name, > > + size_t *values_cnt); > > +void vkms_crc_work_handle(struct work_struct *work); > > + > > #endif /* _VKMS_DRV_H_ */ > > diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c > > index aaf7c35faed6..1e0ee8ca8bd6 100644 > > --- a/drivers/gpu/drm/vkms/vkms_plane.c > > +++ b/drivers/gpu/drm/vkms/vkms_plane.c > > @@ -24,6 +24,16 @@ static const struct drm_plane_funcs vkms_plane_funcs = { > > static void vkms_primary_plane_update(struct drm_plane *plane, > > struct drm_plane_state *old_state) > > { > > + struct vkms_crtc_state *state; > > + > > + if (!plane->state->crtc || !plane->state->fb) > > + return; > > + > > + state = to_vkms_crtc_state(plane->state->crtc->state); > > + memcpy(&state->data.src, &plane->state->src, sizeof(struct drm_rect)); > > + memcpy(&state->data.fb, plane->state->fb, > > + sizeof(struct drm_framebuffer)); > > + drm_framebuffer_get(&state->data.fb); > > } > > > > static int vkms_plane_atomic_check(struct drm_plane *plane, > > -- > > 2.17.1 > > > > -- > Sean Paul, Software Engineer, Google / Chromium OS _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel