[PATCH v3 07/10] drm/msm/A6xx: Add traces for preemption

[Antonino Maniscalco]

Add trace points corresponding to preemption being triggered and being
completed for latency measurement purposes.

Signed-off-by: Antonino Maniscalco <antomani103 at gmail.com>
Tested-by: Neil Armstrong <neil.armstrong at linaro.org> # on SM8650-QRD
---
 drivers/gpu/drm/msm/adreno/a6xx_preempt.c |  7 +++++++
 drivers/gpu/drm/msm/msm_gpu_trace.h       | 28 ++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_preempt.c b/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
index ec44f44d925f..ca9d36c107f2 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
@@ -7,6 +7,7 @@
 #include "a6xx_gpu.h"
 #include "a6xx_gmu.xml.h"
 #include "msm_mmu.h"
+#include "msm_gpu_trace.h"
 
 /*
  * Try to transition the preemption state from old to new. Return
@@ -143,6 +144,8 @@ void a6xx_preempt_irq(struct msm_gpu *gpu)
 
 	set_preempt_state(a6xx_gpu, PREEMPT_NONE);
 
+	trace_msm_gpu_preemption_irq(a6xx_gpu->cur_ring->id);
+
 	/*
 	 * Retrigger preemption to avoid a deadlock that might occur when preemption
 	 * is skipped due to it being already in flight when requested.
@@ -264,6 +267,10 @@ void a6xx_preempt_trigger(struct msm_gpu *gpu)
 	 */
 	ring->skip_inline_wptr = false;
 
+	trace_msm_gpu_preemption_trigger(
+		a6xx_gpu->cur_ring ? a6xx_gpu->cur_ring->id : -1,
+		ring ? ring->id : -1);
+
 	spin_unlock_irqrestore(&ring->preempt_lock, flags);
 
 	gpu_write64(gpu,
diff --git a/drivers/gpu/drm/msm/msm_gpu_trace.h b/drivers/gpu/drm/msm/msm_gpu_trace.h
index ac40d857bc45..7f863282db0d 100644
--- a/drivers/gpu/drm/msm/msm_gpu_trace.h
+++ b/drivers/gpu/drm/msm/msm_gpu_trace.h
@@ -177,6 +177,34 @@ TRACE_EVENT(msm_gpu_resume,
 		TP_printk("%u", __entry->dummy)
 );
 
+TRACE_EVENT(msm_gpu_preemption_trigger,
+		TP_PROTO(int ring_id_from, int ring_id_to),
+		TP_ARGS(ring_id_from, ring_id_to),
+		TP_STRUCT__entry(
+			__field(int, ring_id_from)
+			__field(int, ring_id_to)
+			),
+		TP_fast_assign(
+			__entry->ring_id_from = ring_id_from;
+			__entry->ring_id_to = ring_id_to;
+			),
+		TP_printk("preempting %u -> %u",
+			  __entry->ring_id_from,
+			  __entry->ring_id_to)
+);
+
+TRACE_EVENT(msm_gpu_preemption_irq,
+		TP_PROTO(u32 ring_id),
+		TP_ARGS(ring_id),
+		TP_STRUCT__entry(
+			__field(u32, ring_id)
+			),
+		TP_fast_assign(
+			__entry->ring_id = ring_id;
+			),
+		TP_printk("preempted to %u", __entry->ring_id)
+);
+
 #endif
 
 #undef TRACE_INCLUDE_PATH

-- 
2.46.0