[Bug 97872] GPU hang with libva (gstreamer)

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=97872

--- Comment #18 from Sean V Kelley <seanvk at posteo.de> ---
> On 25 DFómh 2016, at 22:49, bugzilla-daemon at freedesktop.org <mailto:bugzilla-daemon at freedesktop.org> wrote:
> 
> 
> Comment # 16 <https://bugs.freedesktop.org/show_bug.cgi?id=97872#c16> on bug 97872 <https://bugs.freedesktop.org/show_bug.cgi?id=97872> from haihao <mailto:haihao.xiang at intel.com>
> (In reply to Sean V Kelley from comment #13 <x-msg://4/show_bug.cgi?id=97872#c13>)
> > Haihao,
> > 
> > The 2nd VDBOX on SKL is not a complete VDBOX, it only contains MFX. I would
> > recommend shunting all MFX workloads to the 2nd VDBOX and using the 1st
> > VDBOX for HCP, VDENC, HuC.
> 
> Usually user doesn't use different codecs at the same time. I don't think using
> BSD1 only for MFX is better choice for VP8/H264/MPEG2 etc.

You can’t assume that.  In fact, VDENC will likely dominate. 
> > What we need for a permanent fix is an i915
> > kernel patch that manages the loads between the engines based on input from
> > UMD.
> 
> Currently i915 kernel can manage the loads between the engines.  But i915
> kernel doesn't know HCP/HuC commands must be ran from the 2nd ring unless UMD
> driver can tell the kernel. which is why I915_EXEC_BSD_RING1 and
> I915_EXEC_BSD_RING2 are added to the execution ioctl.

Yes, that is the whole point of the patch submitted to the i915, but it is
still a hack.  I’m well aware of how this works.  And that means every time we
use a new codec that is not balanced between the VDBoxen we add the hack flag. 
Again, we need to do better.

Sean
> > 
> > So, while I find you patch servicable for the immediate need, I want to see
> > a long term fix along the lines above that I suggest.  I will look into the
> > kernel patch.
> > 
> > Thanks,
> > 
> > Sean
> 
> You are receiving this mail because:
> You are the QA Contact for the bug.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20161026/f3d5f020/attachment.html>