Re: [PATCH 00/83] AMD HSA kernel driver

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Jul 16, 2014 at 10:21:14AM +0200, Daniel Vetter wrote:
> On Tue, Jul 15, 2014 at 7:53 PM, Bridgman, John <John.Bridgman@amd.com> wrote:
> [snip away the discussion about hsa device discover, I'm hijacking
> this thread just for the event/fence stuff here.]
> 
> > ... There's an event mechanism still to come - mostly for communicating fences and shader interrupts back to userspace, but also used for "device change" notifications, so no polling of sysfs.
> 
> That could would be interesting. On i915 my plan is to internally use
> the recently added struct fence from Maarten. For the external
> interface for userspace that wants explicit control over fences I'm
> leaning towards polishing the android syncpt stuff (currently in
> staging). But in any case I _really_ want to avoid that we end up with
> multiple different and incompatible explicit fencing interfaces on
> linux.

I agree, and I'll say it stronger than that, we WILL NOT have different
and incompatible fencing interfaces in the kernel.  That way lies
madness.

John, take a look at what is now in linux-next, it should provide what
you need here, right?

thanks,

greg k-h