drm/i915: Merge i915_request.flags with i915_request.fence.flags

As we already have a flags field buried within i915_request, reuse it!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200106114234.2529613-3-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c

@@ -2173,7 +2173,7 @@ static int eb_submit(struct i915_execbuffer *eb)
 	}
 
 	if (intel_context_nopreempt(eb->context))
-		eb->request->flags |= I915_REQUEST_NOPREEMPT;
+		__set_bit(I915_FENCE_FLAG_NOPREEMPT, &eb->request->fence.flags);
 
 	return 0;
 }

drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c

@@ -199,7 +199,7 @@ int intel_engine_pulse(struct intel_engine_cs *engine)
 		goto out_unlock;
 	}
 
-	rq->flags |= I915_REQUEST_SENTINEL;
+	__set_bit(I915_FENCE_FLAG_SENTINEL, &rq->fence.flags);
 	idle_pulse(engine, rq);
 
 	__i915_request_commit(rq);

drivers/gpu/drm/i915/gt/intel_lrc.c

@@ -1538,8 +1538,8 @@ static bool can_merge_rq(const struct i915_request *prev,
 	if (i915_request_completed(next))
 		return true;
 
-	if (unlikely((prev->flags ^ next->flags) &
-		     (I915_REQUEST_NOPREEMPT | I915_REQUEST_SENTINEL)))
+	if (unlikely((prev->fence.flags ^ next->fence.flags) &
+		     (I915_FENCE_FLAG_NOPREEMPT | I915_FENCE_FLAG_SENTINEL)))
 		return false;
 
 	if (!can_merge_ctx(prev->context, next->context))

drivers/gpu/drm/i915/gt/intel_rps.c

@@ -777,7 +777,7 @@ void intel_rps_boost(struct i915_request *rq)
 	spin_lock_irqsave(&rq->lock, flags);
 	if (!i915_request_has_waitboost(rq) &&
 	    !dma_fence_is_signaled_locked(&rq->fence)) {
-		rq->flags |= I915_REQUEST_WAITBOOST;
+		set_bit(I915_FENCE_FLAG_BOOST, &rq->fence.flags);
 
 		if (!atomic_fetch_inc(&rps->num_waiters) &&
 		    READ_ONCE(rps->cur_freq) < rps->boost_freq)

drivers/gpu/drm/i915/gt/selftest_lrc.c

@@ -1153,7 +1153,7 @@ static int live_nopreempt(void *arg)
 		}
 
 		/* Low priority client, but unpreemptable! */
-		rq_a->flags |= I915_REQUEST_NOPREEMPT;
+		__set_bit(I915_FENCE_FLAG_NOPREEMPT, &rq_a->fence.flags);
 
 		i915_request_add(rq_a);
 		if (!igt_wait_for_spinner(&a.spin, rq_a)) {

drivers/gpu/drm/i915/i915_request.c

@@ -658,7 +658,6 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp)
 	rq->engine = ce->engine;
 	rq->ring = ce->ring;
 	rq->execution_mask = ce->engine->mask;
-	rq->flags = 0;
 
 	RCU_INIT_POINTER(rq->timeline, tl);
 	RCU_INIT_POINTER(rq->hwsp_cacheline, tl->hwsp_cacheline);

drivers/gpu/drm/i915/i915_request.h

@@ -77,6 +77,38 @@ enum {
 	 * a request is on the various signal_list.
 	 */
 	I915_FENCE_FLAG_SIGNAL,
+
+	/*
+	 * I915_FENCE_FLAG_NOPREEMPT - this request should not be preempted
+	 *
+	 * The execution of some requests should not be interrupted. This is
+	 * a sensitive operation as it makes the request super important,
+	 * blocking other higher priority work. Abuse of this flag will
+	 * lead to quality of service issues.
+	 */
+	I915_FENCE_FLAG_NOPREEMPT,
+
+	/*
+	 * I915_FENCE_FLAG_SENTINEL - this request should be last in the queue
+	 *
+	 * A high priority sentinel request may be submitted to clear the
+	 * submission queue. As it will be the only request in-flight, upon
+	 * execution all other active requests will have been preempted and
+	 * unsubmitted. This preemptive pulse is used to re-evaluate the
+	 * in-flight requests, particularly in cases where an active context
+	 * is banned and those active requests need to be cancelled.
+	 */
+	I915_FENCE_FLAG_SENTINEL,
+
+	/*
+	 * I915_FENCE_FLAG_BOOST - upclock the gpu for this request
+	 *
+	 * Some requests are more important than others! In particular, a
+	 * request that the user is waiting on is typically required for
+	 * interactive latency, for which we want to minimise by upclocking
+	 * the GPU. Here we track such boost requests on a per-request basis.
+	 */
+	I915_FENCE_FLAG_BOOST,
 };
 
 /**
@@ -225,11 +257,6 @@ struct i915_request {
 	/** Time at which this request was emitted, in jiffies. */
 	unsigned long emitted_jiffies;
 
-	unsigned long flags;
-#define I915_REQUEST_WAITBOOST	BIT(0)
-#define I915_REQUEST_NOPREEMPT	BIT(1)
-#define I915_REQUEST_SENTINEL	BIT(2)
-
 	/** timeline->request entry for this request */
 	struct list_head link;
 
@@ -442,18 +469,18 @@ static inline void i915_request_mark_complete(struct i915_request *rq)
 
 static inline bool i915_request_has_waitboost(const struct i915_request *rq)
 {
-	return rq->flags & I915_REQUEST_WAITBOOST;
+	return test_bit(I915_FENCE_FLAG_BOOST, &rq->fence.flags);
 }
 
 static inline bool i915_request_has_nopreempt(const struct i915_request *rq)
 {
 	/* Preemption should only be disabled very rarely */
-	return unlikely(rq->flags & I915_REQUEST_NOPREEMPT);
+	return unlikely(test_bit(I915_FENCE_FLAG_NOPREEMPT, &rq->fence.flags));
 }
 
 static inline bool i915_request_has_sentinel(const struct i915_request *rq)
 {
-	return unlikely(rq->flags & I915_REQUEST_SENTINEL);
+	return unlikely(test_bit(I915_FENCE_FLAG_SENTINEL, &rq->fence.flags));
 }
 
 static inline struct intel_timeline *