[Intel-gfx] [PATCH 18/29] drm/i915: Convert 'trace_irq' to use requests rather than seqnos

[John.C.Harrison at Intel.com]

From: John Harrison <John.C.Harrison at Intel.com>

Updated the trace_irq code to use requests instead of seqnos. This includes
reference counting the request object to ensure it sticks around when required.
Note that getting access to the reference counting functions means moving the
inline i915_trace_irq_get() function from intel_ringbuffer.h to i915_drv.h.

For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h         |    7 +++++++
 drivers/gpu/drm/i915/i915_gem.c         |    6 +++---
 drivers/gpu/drm/i915/i915_trace.h       |    2 +-
 drivers/gpu/drm/i915/intel_ringbuffer.h |    8 +-------
 4 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 3e6082b..6137b51 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3060,4 +3060,11 @@ wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms)
 	}
 }
 
+static inline void i915_trace_irq_get(struct intel_engine_cs *ring,
+				      struct drm_i915_gem_request *req)
+{
+	if (ring->trace_irq_req == NULL && ring->irq_get(ring))
+		i915_gem_request_assign(&ring->trace_irq_req, req);
+}
+
 #endif
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 774ab9f..34dd703 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2714,10 +2714,10 @@ i915_gem_retire_requests_ring(struct intel_engine_cs *ring)
 		i915_gem_free_request(request);
 	}
 
-	if (unlikely(ring->trace_irq_seqno &&
-		     i915_seqno_passed(seqno, ring->trace_irq_seqno))) {
+	if (unlikely(ring->trace_irq_req &&
+		     i915_seqno_passed(seqno, i915_gem_request_get_seqno(ring->trace_irq_req)))) {
 		ring->irq_put(ring);
-		ring->trace_irq_seqno = 0;
+		i915_gem_request_assign(&ring->trace_irq_req, NULL);
 	}
 
 	while (!list_empty(&ring->delayed_free_list)) {
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index 66616f7..0242089 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -369,7 +369,7 @@ TRACE_EVENT(i915_gem_ring_dispatch,
 			   __entry->ring = ring->id;
 			   __entry->seqno = i915_gem_request_get_seqno(req);
 			   __entry->flags = flags;
-			   i915_trace_irq_get(ring, __entry->seqno);
+			   i915_trace_irq_get(ring, req);
 			   ),
 
 	    TP_printk("dev=%u, ring=%u, seqno=%u, flags=%x",
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 0451233..eb754cf5 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -142,7 +142,7 @@ struct  intel_engine_cs {
 
 	unsigned irq_refcount; /* protected by dev_priv->irq_lock */
 	u32		irq_enable_mask;	/* bitmask to enable ring interrupt */
-	u32		trace_irq_seqno;
+	struct drm_i915_gem_request *trace_irq_req;
 	bool __must_check (*irq_get)(struct intel_engine_cs *ring);
 	void		(*irq_put)(struct intel_engine_cs *ring);
 
@@ -437,12 +437,6 @@ intel_ring_get_request(struct intel_engine_cs *ring)
 	return ring->outstanding_lazy_request;
 }
 
-static inline void i915_trace_irq_get(struct intel_engine_cs *ring, u32 seqno)
-{
-	if (ring->trace_irq_seqno == 0 && ring->irq_get(ring))
-		ring->trace_irq_seqno = seqno;
-}
-
 /* DRI warts */
 int intel_render_ring_init_dri(struct drm_device *dev, u64 start, u32 size);
 
-- 
1.7.9.5