[Intel-gfx] [PATCH v6 18/20] drm/i915: Watchdog timeout: DRM kernel interface to set the timeout

[Daniele Ceraolo Spurio]

On 18/04/17 13:23, Michel Thierry wrote:
> Final enablement patch for GPU hang detection using watchdog timeout.
> Using the gem_context_setparam ioctl, users can specify the desired
> timeout value in microseconds, and the driver will do the conversion to
> 'timestamps'.
>
> The recommended default watchdog threshold for video engines is 60000 us,
> since this has been _empirically determined_ to be a good compromise for
> low-latency requirements and low rate of false positives. The default
> register value is ~106000us and the theoretical max value (all 1s) is
> 353 seconds.
>
> Note, UABI engine ids and i915 engine ids are different, and this patch
> uses the i915 ones. Some kind of mapping table [1] is required if we
> decide to use the UABI engine ids.
>
> [1] http://patchwork.freedesktop.org/patch/msgid/20170329135831.30254-2-chris@chris-wilson.co.uk

Now that we have class and instance definitions, could it be worth to 
use those instead to index the engines? If we pair it with the engine 
discovery ioctl that Tvrtko proposed we could have something that is 
reasonably future-proof.

Thanks,
Daniele