[Intel-gfx] [PATCH v2 1/9] drm/i915: Include engine->last_submitted_seqno in GPU error state

[Chris Wilson]

It's useful to look at the last seqno submitted on a particular engine
and compare it against the HWS value to check for irregularities.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c   | 6 ++++--
 drivers/gpu/drm/i915/i915_drv.h       | 1 +
 drivers/gpu/drm/i915/i915_gpu_error.c | 2 ++
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index a2e3af02c292..906e5424e488 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1363,8 +1363,10 @@ static int i915_hangcheck_info(struct seq_file *m, void *unused)
 
 	for_each_engine_id(engine, dev_priv, id) {
 		seq_printf(m, "%s:\n", engine->name);
-		seq_printf(m, "\tseqno = %x [current %x]\n",
-			   engine->hangcheck.seqno, seqno[id]);
+		seq_printf(m, "\tseqno = %x [current %x, last %x]\n",
+			   engine->hangcheck.seqno,
+			   seqno[id],
+			   engine->last_submitted_seqno);
 		seq_printf(m, "\tACTHD = 0x%08llx [current 0x%08llx]\n",
 			   (long long)engine->hangcheck.acthd,
 			   (long long)acthd[id]);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a1f78f275c55..c7ce452d35ad 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -495,6 +495,7 @@ struct drm_i915_error_state {
 		u32 cpu_ring_head;
 		u32 cpu_ring_tail;
 
+		u32 last_seqno;
 		u32 semaphore_seqno[I915_NUM_ENGINES - 1];
 
 		/* Register state */
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 9b55409d91b3..9463cb4e9323 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -296,6 +296,7 @@ static void i915_ring_error_state(struct drm_i915_error_state_buf *m,
 		}
 	}
 	err_printf(m, "  seqno: 0x%08x\n", ring->seqno);
+	err_printf(m, "  last_seqno: 0x%08x\n", ring->last_seqno);
 	err_printf(m, "  waiting: %s\n", yesno(ring->waiting));
 	err_printf(m, "  ring->head: 0x%08x\n", ring->cpu_ring_head);
 	err_printf(m, "  ring->tail: 0x%08x\n", ring->cpu_ring_tail);
@@ -931,6 +932,7 @@ static void i915_record_ring_state(struct drm_device *dev,
 	ering->instpm = I915_READ(RING_INSTPM(engine->mmio_base));
 	ering->seqno = engine->get_seqno(engine, false);
 	ering->acthd = intel_ring_get_active_head(engine);
+	ering->last_seqno = engine->last_submitted_seqno;
 	ering->start = I915_READ_START(engine);
 	ering->head = I915_READ_HEAD(engine);
 	ering->tail = I915_READ_TAIL(engine);
-- 
2.8.0.rc3