Re: [PATCH 7/8] drm/qxl: Use drm_fb_helper deferred_io support

[Daniel Vetter <daniel@ffwll.ch>]

On Wed, Apr 20, 2016 at 05:25:28PM +0200, Noralf Trønnes wrote:
> Use the fbdev deferred io support in drm_fb_helper.
> The (struct fb_ops *)->fb_{fillrect,copyarea,imageblit} functions will
> now be deferred in the same way that mmap damage is, instead of being
> flushed directly.
> This patch has only been compile tested.
> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> ---
>  drivers/gpu/drm/qxl/qxl_display.c |   9 +-
>  drivers/gpu/drm/qxl/qxl_drv.h     |   7 +-
>  drivers/gpu/drm/qxl/qxl_fb.c      | 220 ++++++++++----------------------------
>  drivers/gpu/drm/qxl/qxl_kms.c     |   4 -
>  4 files changed, 62 insertions(+), 178 deletions(-)
> 
> diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
> index 030409a..9a03524 100644
> --- a/drivers/gpu/drm/qxl/qxl_display.c
> +++ b/drivers/gpu/drm/qxl/qxl_display.c
> @@ -465,7 +465,7 @@ static const struct drm_crtc_funcs qxl_crtc_funcs = {
>  	.page_flip = qxl_crtc_page_flip,
>  };
>  
> -static void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb)
> +void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb)
>  {
>  	struct qxl_framebuffer *qxl_fb = to_qxl_framebuffer(fb);
>  
> @@ -527,12 +527,13 @@ int
>  qxl_framebuffer_init(struct drm_device *dev,
>  		     struct qxl_framebuffer *qfb,
>  		     const struct drm_mode_fb_cmd2 *mode_cmd,
> -		     struct drm_gem_object *obj)
> +		     struct drm_gem_object *obj,
> +		     const struct drm_framebuffer_funcs *funcs)

There should be no need at all to have a separate fb funcs table for the
fbdev fb. Both /should/ be able to use the exact same (already existing)
->dirty() callback. We need this only in CMA because CMA is a midlayer
used by multiple drivers.

With that change you should be able to condense this patch down to pretty
much just removing lines. Which is Good (tm).

Cheers, Daniel

>  {
>  	int ret;
>  
>  	qfb->obj = obj;
> -	ret = drm_framebuffer_init(dev, &qfb->base, &qxl_fb_funcs);
> +	ret = drm_framebuffer_init(dev, &qfb->base, funcs);
>  	if (ret) {
>  		qfb->obj = NULL;
>  		return ret;
> @@ -999,7 +1000,7 @@ qxl_user_framebuffer_create(struct drm_device *dev,
>  	if (qxl_fb == NULL)
>  		return NULL;
>  
> -	ret = qxl_framebuffer_init(dev, qxl_fb, mode_cmd, obj);
> +	ret = qxl_framebuffer_init(dev, qxl_fb, mode_cmd, obj, &qxl_fb_funcs);
>  	if (ret) {
>  		kfree(qxl_fb);
>  		drm_gem_object_unreference_unlocked(obj);
> diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h
> index 3f3897e..3ad6604 100644
> --- a/drivers/gpu/drm/qxl/qxl_drv.h
> +++ b/drivers/gpu/drm/qxl/qxl_drv.h
> @@ -324,8 +324,6 @@ struct qxl_device {
>  	struct workqueue_struct *gc_queue;
>  	struct work_struct gc_work;
>  
> -	struct work_struct fb_work;
> -
>  	struct drm_property *hotplug_mode_update_property;
>  	int monitors_config_width;
>  	int monitors_config_height;
> @@ -389,11 +387,13 @@ int qxl_get_handle_for_primary_fb(struct qxl_device *qdev,
>  void qxl_fbdev_set_suspend(struct qxl_device *qdev, int state);
>  
>  /* qxl_display.c */
> +void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb);
>  int
>  qxl_framebuffer_init(struct drm_device *dev,
>  		     struct qxl_framebuffer *rfb,
>  		     const struct drm_mode_fb_cmd2 *mode_cmd,
> -		     struct drm_gem_object *obj);
> +		     struct drm_gem_object *obj,
> +		     const struct drm_framebuffer_funcs *funcs);
>  void qxl_display_read_client_monitors_config(struct qxl_device *qdev);
>  void qxl_send_monitors_config(struct qxl_device *qdev);
>  int qxl_create_monitors_object(struct qxl_device *qdev);
> @@ -553,7 +553,6 @@ int qxl_irq_init(struct qxl_device *qdev);
>  irqreturn_t qxl_irq_handler(int irq, void *arg);
>  
>  /* qxl_fb.c */
> -int qxl_fb_init(struct qxl_device *qdev);
>  bool qxl_fbdev_qobj_is_fb(struct qxl_device *qdev, struct qxl_bo *qobj);
>  
>  int qxl_debugfs_add_files(struct qxl_device *qdev,
> diff --git a/drivers/gpu/drm/qxl/qxl_fb.c b/drivers/gpu/drm/qxl/qxl_fb.c
> index 06f032d..090dcee 100644
> --- a/drivers/gpu/drm/qxl/qxl_fb.c
> +++ b/drivers/gpu/drm/qxl/qxl_fb.c
> @@ -30,6 +30,7 @@
>  #include "drm/drm.h"
>  #include "drm/drm_crtc.h"
>  #include "drm/drm_crtc_helper.h"
> +#include "drm/drm_rect.h"
>  #include "qxl_drv.h"
>  
>  #include "qxl_object.h"
> @@ -46,15 +47,6 @@ struct qxl_fbdev {
>  	struct list_head delayed_ops;
>  	void *shadow;
>  	int size;
> -
> -	/* dirty memory logging */
> -	struct {
> -		spinlock_t lock;
> -		unsigned x1;
> -		unsigned y1;
> -		unsigned x2;
> -		unsigned y2;
> -	} dirty;
>  };
>  
>  static void qxl_fb_image_init(struct qxl_fb_image *qxl_fb_image,
> @@ -82,169 +74,18 @@ static void qxl_fb_image_init(struct qxl_fb_image *qxl_fb_image,
>  	}
>  }
>  
> -static void qxl_fb_dirty_flush(struct fb_info *info)
> -{
> -	struct qxl_fbdev *qfbdev = info->par;
> -	struct qxl_device *qdev = qfbdev->qdev;
> -	struct qxl_fb_image qxl_fb_image;
> -	struct fb_image *image = &qxl_fb_image.fb_image;
> -	unsigned long flags;
> -	u32 x1, x2, y1, y2;
> -
> -	/* TODO: hard coding 32 bpp */
> -	int stride = qfbdev->qfb.base.pitches[0];
> -
> -	spin_lock_irqsave(&qfbdev->dirty.lock, flags);
> -
> -	x1 = qfbdev->dirty.x1;
> -	x2 = qfbdev->dirty.x2;
> -	y1 = qfbdev->dirty.y1;
> -	y2 = qfbdev->dirty.y2;
> -	qfbdev->dirty.x1 = 0;
> -	qfbdev->dirty.x2 = 0;
> -	qfbdev->dirty.y1 = 0;
> -	qfbdev->dirty.y2 = 0;
> -
> -	spin_unlock_irqrestore(&qfbdev->dirty.lock, flags);
> -
> -	/*
> -	 * we are using a shadow draw buffer, at qdev->surface0_shadow
> -	 */
> -	qxl_io_log(qdev, "dirty x[%d, %d], y[%d, %d]", x1, x2, y1, y2);
> -	image->dx = x1;
> -	image->dy = y1;
> -	image->width = x2 - x1 + 1;
> -	image->height = y2 - y1 + 1;
> -	image->fg_color = 0xffffffff; /* unused, just to avoid uninitialized
> -					 warnings */
> -	image->bg_color = 0;
> -	image->depth = 32;	     /* TODO: take from somewhere? */
> -	image->cmap.start = 0;
> -	image->cmap.len = 0;
> -	image->cmap.red = NULL;
> -	image->cmap.green = NULL;
> -	image->cmap.blue = NULL;
> -	image->cmap.transp = NULL;
> -	image->data = qfbdev->shadow + (x1 * 4) + (stride * y1);
> -
> -	qxl_fb_image_init(&qxl_fb_image, qdev, info, NULL);
> -	qxl_draw_opaque_fb(&qxl_fb_image, stride);
> -}
> -
> -static void qxl_dirty_update(struct qxl_fbdev *qfbdev,
> -			     int x, int y, int width, int height)
> -{
> -	struct qxl_device *qdev = qfbdev->qdev;
> -	unsigned long flags;
> -	int x2, y2;
> -
> -	x2 = x + width - 1;
> -	y2 = y + height - 1;
> -
> -	spin_lock_irqsave(&qfbdev->dirty.lock, flags);
> -
> -	if ((qfbdev->dirty.y2 - qfbdev->dirty.y1) &&
> -	    (qfbdev->dirty.x2 - qfbdev->dirty.x1)) {
> -		if (qfbdev->dirty.y1 < y)
> -			y = qfbdev->dirty.y1;
> -		if (qfbdev->dirty.y2 > y2)
> -			y2 = qfbdev->dirty.y2;
> -		if (qfbdev->dirty.x1 < x)
> -			x = qfbdev->dirty.x1;
> -		if (qfbdev->dirty.x2 > x2)
> -			x2 = qfbdev->dirty.x2;
> -	}
> -
> -	qfbdev->dirty.x1 = x;
> -	qfbdev->dirty.x2 = x2;
> -	qfbdev->dirty.y1 = y;
> -	qfbdev->dirty.y2 = y2;
> -
> -	spin_unlock_irqrestore(&qfbdev->dirty.lock, flags);
> -
> -	schedule_work(&qdev->fb_work);
> -}
> -
> -static void qxl_deferred_io(struct fb_info *info,
> -			    struct list_head *pagelist)
> -{
> -	struct qxl_fbdev *qfbdev = info->par;
> -	unsigned long start, end, min, max;
> -	struct page *page;
> -	int y1, y2;
> -
> -	min = ULONG_MAX;
> -	max = 0;
> -	list_for_each_entry(page, pagelist, lru) {
> -		start = page->index << PAGE_SHIFT;
> -		end = start + PAGE_SIZE - 1;
> -		min = min(min, start);
> -		max = max(max, end);
> -	}
> -
> -	if (min < max) {
> -		y1 = min / info->fix.line_length;
> -		y2 = (max / info->fix.line_length) + 1;
> -		qxl_dirty_update(qfbdev, 0, y1, info->var.xres, y2 - y1);
> -	}
> -};
> -
>  static struct fb_deferred_io qxl_defio = {
>  	.delay		= QXL_DIRTY_DELAY,
> -	.deferred_io	= qxl_deferred_io,
> +	.deferred_io	= drm_fb_helper_deferred_io,
>  };
>  
> -static void qxl_fb_fillrect(struct fb_info *info,
> -			    const struct fb_fillrect *rect)
> -{
> -	struct qxl_fbdev *qfbdev = info->par;
> -
> -	sys_fillrect(info, rect);
> -	qxl_dirty_update(qfbdev, rect->dx, rect->dy, rect->width,
> -			 rect->height);
> -}
> -
> -static void qxl_fb_copyarea(struct fb_info *info,
> -			    const struct fb_copyarea *area)
> -{
> -	struct qxl_fbdev *qfbdev = info->par;
> -
> -	sys_copyarea(info, area);
> -	qxl_dirty_update(qfbdev, area->dx, area->dy, area->width,
> -			 area->height);
> -}
> -
> -static void qxl_fb_imageblit(struct fb_info *info,
> -			     const struct fb_image *image)
> -{
> -	struct qxl_fbdev *qfbdev = info->par;
> -
> -	sys_imageblit(info, image);
> -	qxl_dirty_update(qfbdev, image->dx, image->dy, image->width,
> -			 image->height);
> -}
> -
> -static void qxl_fb_work(struct work_struct *work)
> -{
> -	struct qxl_device *qdev = container_of(work, struct qxl_device, fb_work);
> -	struct qxl_fbdev *qfbdev = qdev->mode_info.qfbdev;
> -
> -	qxl_fb_dirty_flush(qfbdev->helper.fbdev);
> -}
> -
> -int qxl_fb_init(struct qxl_device *qdev)
> -{
> -	INIT_WORK(&qdev->fb_work, qxl_fb_work);
> -	return 0;
> -}
> -
>  static struct fb_ops qxlfb_ops = {
>  	.owner = THIS_MODULE,
>  	.fb_check_var = drm_fb_helper_check_var,
>  	.fb_set_par = drm_fb_helper_set_par, /* TODO: copy vmwgfx */
> -	.fb_fillrect = qxl_fb_fillrect,
> -	.fb_copyarea = qxl_fb_copyarea,
> -	.fb_imageblit = qxl_fb_imageblit,
> +	.fb_fillrect = drm_fb_helper_sys_fillrect,
> +	.fb_copyarea = drm_fb_helper_sys_copyarea,
> +	.fb_imageblit = drm_fb_helper_sys_imageblit,
>  	.fb_pan_display = drm_fb_helper_pan_display,
>  	.fb_blank = drm_fb_helper_blank,
>  	.fb_setcmap = drm_fb_helper_setcmap,
> @@ -338,6 +179,53 @@ out_unref:
>  	return ret;
>  }
>  
> +static int qxlfb_framebuffer_dirty(struct drm_framebuffer *fb,
> +				   struct drm_file *file_priv,
> +				   unsigned flags, unsigned color,
> +				   struct drm_clip_rect *clips,
> +				   unsigned num_clips)
> +{
> +	struct qxl_device *qdev = fb->dev->dev_private;
> +	struct fb_info *info = qdev->fbdev_info;
> +	struct qxl_fbdev *qfbdev = info->par;
> +	struct qxl_fb_image qxl_fb_image;
> +	struct fb_image *image = &qxl_fb_image.fb_image;
> +
> +	/* TODO: hard coding 32 bpp */
> +	int stride = qfbdev->qfb.base.pitches[0];
> +
> +	/*
> +	 * we are using a shadow draw buffer, at qdev->surface0_shadow
> +	 */
> +	qxl_io_log(qdev, "dirty x[%d, %d], y[%d, %d]", clips->x1, clips->x2,
> +		   clips->y1, clips->y2);
> +	image->dx = clips->x1;
> +	image->dy = clips->y1;
> +	image->width = drm_clip_rect_width(clips);
> +	image->height = drm_clip_rect_height(clips);
> +	image->fg_color = 0xffffffff; /* unused, just to avoid uninitialized
> +					 warnings */
> +	image->bg_color = 0;
> +	image->depth = 32;	     /* TODO: take from somewhere? */
> +	image->cmap.start = 0;
> +	image->cmap.len = 0;
> +	image->cmap.red = NULL;
> +	image->cmap.green = NULL;
> +	image->cmap.blue = NULL;
> +	image->cmap.transp = NULL;
> +	image->data = qfbdev->shadow + (clips->x1 * 4) + (stride * clips->y1);
> +
> +	qxl_fb_image_init(&qxl_fb_image, qdev, info, NULL);
> +	qxl_draw_opaque_fb(&qxl_fb_image, stride);
> +
> +	return 0;
> +}
> +
> +static const struct drm_framebuffer_funcs qxlfb_fb_funcs = {
> +	.destroy = qxl_user_framebuffer_destroy,
> +	.dirty = qxlfb_framebuffer_dirty,
> +};
> +
>  static int qxlfb_create(struct qxl_fbdev *qfbdev,
>  			struct drm_fb_helper_surface_size *sizes)
>  {
> @@ -383,7 +271,8 @@ static int qxlfb_create(struct qxl_fbdev *qfbdev,
>  
>  	info->par = qfbdev;
>  
> -	qxl_framebuffer_init(qdev->ddev, &qfbdev->qfb, &mode_cmd, gobj);
> +	qxl_framebuffer_init(qdev->ddev, &qfbdev->qfb, &mode_cmd, gobj,
> +			     &qxlfb_fb_funcs);
>  
>  	fb = &qfbdev->qfb.base;
>  
> @@ -504,7 +393,6 @@ int qxl_fbdev_init(struct qxl_device *qdev)
>  	qfbdev->qdev = qdev;
>  	qdev->mode_info.qfbdev = qfbdev;
>  	spin_lock_init(&qfbdev->delayed_ops_lock);
> -	spin_lock_init(&qfbdev->dirty.lock);
>  	INIT_LIST_HEAD(&qfbdev->delayed_ops);
>  
>  	drm_fb_helper_prepare(qdev->ddev, &qfbdev->helper,
> diff --git a/drivers/gpu/drm/qxl/qxl_kms.c b/drivers/gpu/drm/qxl/qxl_kms.c
> index b2977a1..2319800 100644
> --- a/drivers/gpu/drm/qxl/qxl_kms.c
> +++ b/drivers/gpu/drm/qxl/qxl_kms.c
> @@ -261,10 +261,6 @@ static int qxl_device_init(struct qxl_device *qdev,
>  	qdev->gc_queue = create_singlethread_workqueue("qxl_gc");
>  	INIT_WORK(&qdev->gc_work, qxl_gc_work);
>  
> -	r = qxl_fb_init(qdev);
> -	if (r)
> -		return r;
> -
>  	return 0;
>  }
>  
> -- 
> 2.2.2
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch