[Intel-gfx] [PATCH v2] drm/i915: suppress atomic commit error message under gvt-g env

[Niu, Bing]

Hi ville:
thanks for acked-by and will fix that missing space :)

-----Original Message-----
From: Ville Syrjälä [mailto:ville.syrjala at linux.intel.com] 
Sent: Wednesday, March 08, 2017 12:13 AM
To: Niu, Bing <bing.niu at intel.com>
Cc: intel-gfx at lists.freedesktop.org; Lv, Zhiyuan <zhiyuan.lv at intel.com>; Wang, Zhi A <zhi.a.wang at intel.com>
Subject: Re: [Intel-gfx][PATCH v2] drm/i915: suppress atomic commit error message under gvt-g env

On Tue, Mar 07, 2017 at 12:46:35PM -0500, bing.niu at intel.com wrote:
> From: Bing Niu <bing.niu at intel.com>
> 
> under virtualization enviroment, it is possible guest update pipe 
> registers across vblank intervals due to overhead of mmio traps or vm 
> schedule out. However, it is safe since those pipe update happen in 
> virual registers and will not be committed to hardware. suppress that 
> atomic commit error message under virtualization case to avoid 
> confusing user.
> 
> v2: per ville's comment: return early and against Maarten's patch
> 
> Signed-off-by: Bing Niu <bing.niu at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_sprite.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_sprite.c 
> b/drivers/gpu/drm/i915/intel_sprite.c
> index 375ca91..b7849ca 100644
> --- a/drivers/gpu/drm/i915/intel_sprite.c
> +++ b/drivers/gpu/drm/i915/intel_sprite.c
> @@ -161,6 +161,7 @@ void intel_pipe_update_end(struct intel_crtc *crtc, struct intel_flip_work *work
>  	int scanline_end = intel_get_crtc_scanline(crtc);
>  	u32 end_vbl_count = intel_crtc_get_vblank_counter(crtc);
>  	ktime_t end_vbl_time = ktime_get();
> +	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
>  
>  	if (work) {
>  		work->flip_queued_vblank = end_vbl_count; @@ -186,6 +187,9 @@ void 
> intel_pipe_update_end(struct intel_crtc *crtc, struct intel_flip_work 
> *work
>  
>  	local_irq_enable();
>  
> +	if(intel_vgpu_active(dev_priv))
          ^
missing space	  

I don't understand why it's OK fail atomicity guarantees for vgpu, but I don't really care either. So I'm fine with this.

Acked-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

> +		return;
> +
>  	if (crtc->debug.start_vbl_count &&
>  	    crtc->debug.start_vbl_count != end_vbl_count) {
>  		DRM_ERROR("Atomic update failure on pipe %c (start=%u end=%u) time 
> %lld us, min %d, max %d, scanline start %d, end %d\n",
> --
> 2.7.4

--
Ville Syrjälä
Intel OTC