From 4fd506cfe132471735407da41f2cf3ca8ffbbed9 Mon Sep 17 00:00:00 2001
From: German Andryeyev <German.Andryeyev@amd.com>
Date: Wed, 30 Jun 2021 14:36:10 -0400
Subject: [PATCH] SWDEV-289378 - Avoid CPU TS overwrite if GPU TS is available

Change-Id: I2fc1a43c048b4fa1e42f27c4cf5c72fc7ae84e9c
---
 rocclr/device/rocm/rocvirtual.hpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/rocclr/device/rocm/rocvirtual.hpp b/rocclr/device/rocm/rocvirtual.hpp
index 64f556e412..fcf75b094e 100644
--- a/rocclr/device/rocm/rocvirtual.hpp
+++ b/rocclr/device/rocm/rocvirtual.hpp
@@ -131,7 +131,14 @@ class Timestamp : public amd::HeapObject {
   void start() { start_ = amd::Os::timeNanos(); }
 
   // End a timestamp (get timestamp from OS)
-  void end() { end_ = amd::Os::timeNanos(); }
+  void end() {
+    // Timestamp value can be updated by HW profiling if current command had a stall.
+    // Although CPU TS should be still valid in this situation, there are cases in VM mode
+    // when CPU timeline is out of sync with GPU timeline and shifted time can be reported
+    if (end_ != 0) {
+      end_ = amd::Os::timeNanos();
+    }
+  }
 
   static void setGpuTicksToTime(double ticksToTime) { ticksToTime_ = ticksToTime; }
   static double getGpuTicksToTime() { return ticksToTime_; }