[Intel-gfx] [PATCH 14/17] drm/i915: Add stats for GuC log buffer flush interrupts

[akash.goel at intel.com]

From: Akash Goel <akash.goel at intel.com>

GuC firmware sends an interrupt to flush the log buffer when it
becomes half full. GuC firmware also tracks how many times the
buffer overflowed.
It would be useful to maintain a statistics of how many flush
interrupts were received and for which type of log buffer,
along with the overflow count of each buffer type.
Augmented i915_log_info debugfs to report back these statistics.

Signed-off-by: Akash Goel <akash.goel at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c        | 26 ++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_guc_submission.c |  8 ++++++++
 drivers/gpu/drm/i915/i915_irq.c            |  1 +
 drivers/gpu/drm/i915/intel_guc.h           |  6 ++++++
 4 files changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 3c9c7f7..888a18a 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2538,6 +2538,30 @@ static int i915_guc_load_status_info(struct seq_file *m, void *data)
 	return 0;
 }
 
+static void i915_guc_log_info(struct seq_file *m,
+				 struct drm_i915_private *dev_priv)
+{
+	struct intel_guc *guc = &dev_priv->guc;
+
+	seq_printf(m, "\nGuC logging stats:\n");
+
+	seq_printf(m, "\tISR:   flush count %10u, overflow count %8u\n",
+		guc->log.flush_count[GUC_ISR_LOG_BUFFER],
+		guc->log.total_overflow_count[GUC_ISR_LOG_BUFFER]);
+
+	seq_printf(m, "\tDPC:   flush count %10u, overflow count %8u\n",
+		guc->log.flush_count[GUC_DPC_LOG_BUFFER],
+		guc->log.total_overflow_count[GUC_DPC_LOG_BUFFER]);
+
+	seq_printf(m, "\tCRASH: flush count %10u, overflow count %8u\n",
+		guc->log.flush_count[GUC_CRASH_DUMP_LOG_BUFFER],
+		guc->log.total_overflow_count[GUC_CRASH_DUMP_LOG_BUFFER]);
+
+	seq_printf(m, "\tTotal flush interrupt count: %u\n",
+			guc->log.flush_interrupt_count);
+
+}
+
 static void i915_guc_client_info(struct seq_file *m,
 				 struct drm_i915_private *dev_priv,
 				 struct i915_guc_client *client)
@@ -2611,6 +2635,8 @@ static int i915_guc_info(struct seq_file *m, void *data)
 	seq_printf(m, "\nGuC execbuf client @ %p:\n", guc.execbuf_client);
 	i915_guc_client_info(m, dev_priv, &client);
 
+	i915_guc_log_info(m, dev_priv);
+
 	/* Add more as required ... */
 
 	return 0;
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index c1e637f..9c94a43 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -914,6 +914,14 @@ static void guc_read_update_log_buffer(struct drm_device *dev)
 		log_buffer_state_local = *log_buffer_state;
 		buffer_size = log_buffer_state_local.size;
 
+		guc->log.flush_count[i] += log_buffer_state_local.flush_to_file;
+		if (log_buffer_state_local.buffer_full_cnt !=
+					guc->log.prev_overflow_count[i]) {
+			guc->log.prev_overflow_count[i] =
+					log_buffer_state_local.buffer_full_cnt;
+			guc->log.total_overflow_count[i]++;
+		}
+
 		if (log_buffer_copy_state) {
 			/* First copy the state structure */
 			memcpy(log_buffer_copy_state, &log_buffer_state_local,
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index bdd7a67..c3fb67e 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1711,6 +1711,7 @@ static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 gt_iir)
 						&dev_priv->guc.events_work);
 			}
 		}
+		dev_priv->guc.log.flush_interrupt_count++;
 		spin_unlock(&dev_priv->irq_lock);
 	}
 }
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
index 611f4a7..e911a32 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -128,6 +128,12 @@ struct intel_guc_log {
 	struct workqueue_struct *wq;
 	void *buf_addr;
 	struct rchan *relay_chan;
+
+	/* logging related stats */
+	u32 flush_interrupt_count;
+	u32 prev_overflow_count[GUC_MAX_LOG_BUFFER];
+	u32 total_overflow_count[GUC_MAX_LOG_BUFFER];
+	u32 flush_count[GUC_MAX_LOG_BUFFER];
 };
 
 struct intel_guc {
-- 
1.9.2