[Intel-gfx] [PATCH v2 1/3] drm/i915: Check for matching ringbuffer in logical_ring_wait_request()

[Deepak S]

On Wednesday 19 November 2014 01:37 AM, Dave Gordon wrote:
> The request queue is per-engine, and may therefore contain requests
> from several different contexts/ringbuffers. In determining which
> request to wait for, this function should only consider requests
> from the ringbuffer that it's checking for space, and ignore any
> that it finds that belong to other contexts.
>
> Signed-off-by: Dave Gordon <david.s.gordon at intel.com>
> ---
>   drivers/gpu/drm/i915/intel_lrc.c |   10 ++++++++++
>   1 file changed, 10 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index 2a1a719..1003b3a 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -835,6 +835,16 @@ static int logical_ring_wait_request(struct intel_ringbuffer *ringbuf,
>   	}
>   
>   	list_for_each_entry(request, &ring->request_list, list) {
> +		/*
> +		 * The request queue is per-engine, so can contain requests
> +		 * from multiple ringbuffers. Here, we must ignore any that
> +		 * aren't from the ringbuffer we're considering.
> +		 */
> +		struct intel_context *ctx = request->ctx;
> +		if (ctx->engine[ring->id].ringbuf != ringbuf)
> +			continue;
> +
> +		/* Would completion of this request free enough space? */
>   		if (__intel_ring_space(request->tail, ringbuf->tail,
>   				       ringbuf->size) >= bytes) {
>   			seqno = request->seqno;

Looks fine to me
Reviewed-by: Deepak S <deepak.s at linux.intel.com>