[Intel-gfx] [PATCH 1/1] Let userspace know if they can trust timeslicing by including it as part of the I915_PARAM_HAS_SCHEDULER::I915_SCHEDULER_CAP_TIMESLICING

[Tvrtko Ursulin]

+ dri-devel as per process

On 25/05/2021 14:55, Tejas Upadhyay wrote:
> v2: Only declare timeslicing if we can safely preempt userspace.

Commit message got butchered up somehow so you'll need to fix that at 
some point.

Regards,

Tvrtko

> Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing")
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>   drivers/gpu/drm/i915/gt/intel_engine_user.c | 1 +
>   include/uapi/drm/i915_drm.h                 | 1 +
>   2 files changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c
> index 3cca7ea2d6ea..12d165566ed2 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_user.c
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c
> @@ -98,6 +98,7 @@ static void set_scheduler_caps(struct drm_i915_private *i915)
>   		MAP(HAS_PREEMPTION, PREEMPTION),
>   		MAP(HAS_SEMAPHORES, SEMAPHORES),
>   		MAP(SUPPORTS_STATS, ENGINE_BUSY_STATS),
> +		MAP(TIMESLICE_BIT, TIMESLICING),
>   #undef MAP
>   	};
>   	struct intel_engine_cs *engine;
> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index c2c7759b7d2e..af2212d6113c 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -572,6 +572,7 @@ typedef struct drm_i915_irq_wait {
>   #define   I915_SCHEDULER_CAP_PREEMPTION	(1ul << 2)
>   #define   I915_SCHEDULER_CAP_SEMAPHORES	(1ul << 3)
>   #define   I915_SCHEDULER_CAP_ENGINE_BUSY_STATS	(1ul << 4)
> +#define   I915_SCHEDULER_CAP_TIMESLICING	(1ul << 5)
>   
>   #define I915_PARAM_HUC_STATUS		 42
>   
>