[Intel-gfx] [PATCH 01/55] drm/i915: Re-instate request->uniq becuase it is extremely useful

[John.C.Harrison at Intel.com]

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

The seqno value cannot always be used when debugging issues via trace
points. This is because it can be reset back to start, especially
during TDR type tests. Also, when the scheduler arrives the seqno is
only valid while a given request is executing on the hardware. While
the request is simply queued waiting for submission, it's seqno value
will be zero (meaning invalid).

For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h   |    4 ++++
 drivers/gpu/drm/i915/i915_gem.c   |    1 +
 drivers/gpu/drm/i915/i915_trace.h |   13 +++++++++----
 drivers/gpu/drm/i915/intel_lrc.c  |    2 ++
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1038f5c..0347eb9 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1882,6 +1882,8 @@ struct drm_i915_private {
 
 	bool edp_low_vswing;
 
+	uint32_t request_uniq;
+
 	/*
 	 * NOTE: This is the dri1/ums dungeon, don't add stuff here. Your patch
 	 * will be rejected. Instead look for a better place.
@@ -2160,6 +2162,8 @@ struct drm_i915_gem_request {
 	/** process identifier submitting this request */
 	struct pid *pid;
 
+	uint32_t uniq;
+
 	/**
 	 * The ELSP only accepts two elements at a time, so we queue
 	 * context/tail pairs on a given queue (ring->execlist_queue) until the
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index cc206f1..68f1d1e 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2657,6 +2657,7 @@ int i915_gem_request_alloc(struct intel_engine_cs *ring,
 		goto err;
 
 	req->ring = ring;
+	req->uniq = dev_priv->request_uniq++;
 
 	if (i915.enable_execlists)
 		ret = intel_logical_ring_alloc_request_extras(req, ctx);
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index 497cba5..6cbc280 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -504,6 +504,7 @@ DECLARE_EVENT_CLASS(i915_gem_request,
 	    TP_STRUCT__entry(
 			     __field(u32, dev)
 			     __field(u32, ring)
+			     __field(u32, uniq)
 			     __field(u32, seqno)
 			     ),
 
@@ -512,11 +513,13 @@ DECLARE_EVENT_CLASS(i915_gem_request,
 						i915_gem_request_get_ring(req);
 			   __entry->dev = ring->dev->primary->index;
 			   __entry->ring = ring->id;
+			   __entry->uniq = req ? req->uniq : 0;
 			   __entry->seqno = i915_gem_request_get_seqno(req);
 			   ),
 
-	    TP_printk("dev=%u, ring=%u, seqno=%u",
-		      __entry->dev, __entry->ring, __entry->seqno)
+	    TP_printk("dev=%u, ring=%u, uniq=%u, seqno=%u",
+		      __entry->dev, __entry->ring, __entry->uniq,
+		      __entry->seqno)
 );
 
 DEFINE_EVENT(i915_gem_request, i915_gem_request_add,
@@ -561,6 +564,7 @@ TRACE_EVENT(i915_gem_request_wait_begin,
 	    TP_STRUCT__entry(
 			     __field(u32, dev)
 			     __field(u32, ring)
+			     __field(u32, uniq)
 			     __field(u32, seqno)
 			     __field(bool, blocking)
 			     ),
@@ -576,13 +580,14 @@ TRACE_EVENT(i915_gem_request_wait_begin,
 						i915_gem_request_get_ring(req);
 			   __entry->dev = ring->dev->primary->index;
 			   __entry->ring = ring->id;
+			   __entry->uniq = req ? req->uniq : 0;
 			   __entry->seqno = i915_gem_request_get_seqno(req);
 			   __entry->blocking =
 				     mutex_is_locked(&ring->dev->struct_mutex);
 			   ),
 
-	    TP_printk("dev=%u, ring=%u, seqno=%u, blocking=%s",
-		      __entry->dev, __entry->ring,
+	    TP_printk("dev=%u, ring=%u, uniq=%u, seqno=%u, blocking=%s",
+		      __entry->dev, __entry->ring, __entry->uniq,
 		      __entry->seqno, __entry->blocking ?  "yes (NB)" : "no")
 );
 
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 96ae90a..6a5ed07 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -549,6 +549,7 @@ static int execlists_context_queue(struct intel_engine_cs *ring,
 				   struct drm_i915_gem_request *request)
 {
 	struct drm_i915_gem_request *cursor;
+	struct drm_i915_private *dev_priv = ring->dev->dev_private;
 	int num_elements = 0;
 
 	if (to != ring->default_context)
@@ -565,6 +566,7 @@ static int execlists_context_queue(struct intel_engine_cs *ring,
 		request->ring = ring;
 		request->ctx = to;
 		kref_init(&request->ref);
+		request->uniq = dev_priv->request_uniq++;
 		i915_gem_context_reference(request->ctx);
 	} else {
 		i915_gem_request_reference(request);
-- 
1.7.9.5