From 8e4f2a4d593d765a722cc983d201e63e615e9b0f Mon Sep 17 00:00:00 2001
From: Andre Puschmann <andre@softwareradiosystems.com>
Date: Wed, 26 Feb 2020 10:50:40 +0100
Subject: [PATCH] add UE parameter to enable TTI stats calculations

---
 srsue/hdr/stack/ue_stack_base.h |  1 +
 srsue/src/main.cc               |  6 +++++-
 srsue/src/stack/ue_stack_lte.cc | 16 +++++++++-------
 srsue/ue.conf.example           |  3 +++
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/srsue/hdr/stack/ue_stack_base.h b/srsue/hdr/stack/ue_stack_base.h
index cfd17c127..2a23961ab 100644
--- a/srsue/hdr/stack/ue_stack_base.h
+++ b/srsue/hdr/stack/ue_stack_base.h
@@ -66,6 +66,7 @@ typedef struct {
   std::string      ue_category_str;
   nas_args_t       nas;
   gw_args_t        gw;
+  bool             have_tti_time_stats;
 } stack_args_t;
 
 class ue_stack_base
diff --git a/srsue/src/main.cc b/srsue/src/main.cc
index 3d7b9c21f..4fdee34ae 100644
--- a/srsue/src/main.cc
+++ b/srsue/src/main.cc
@@ -366,7 +366,11 @@ static int parse_args(all_args_t* args, int argc, char* argv[])
 
     ("general.metrics_csv_filename",
        bpo::value<string>(&args->general.metrics_csv_filename)->default_value("/tmp/ue_metrics.csv"),
-       "Metrics CSV filename");
+       "Metrics CSV filename")
+
+    ("stack.have_tti_time_stats",
+        bpo::value<bool>(&args->stack.have_tti_time_stats)->default_value(true),
+        "Calculate TTI execution statistics");
 
   // Positional options - config file location
   bpo::options_description position("Positional options");
diff --git a/srsue/src/stack/ue_stack_lte.cc b/srsue/src/stack/ue_stack_lte.cc
index 175051089..59eb762dc 100644
--- a/srsue/src/stack/ue_stack_lte.cc
+++ b/srsue/src/stack/ue_stack_lte.cc
@@ -295,8 +295,15 @@ void ue_stack_lte::run_tti_impl(uint32_t tti)
   nas.run_tti(tti);
   timers.step_all();
 
-  auto end = std::chrono::steady_clock::now();
-  calc_tti_stats(std::chrono::duration_cast<std::chrono::microseconds>(end - start).count());
+  if (args.have_tti_time_stats) {
+    auto end = std::chrono::steady_clock::now();
+    calc_tti_stats(std::chrono::duration_cast<std::chrono::microseconds>(end - start).count());
+  }
+
+  // print warning if PHY pushes new TTI messages faster than we process them
+  if (pending_tasks.size(sync_queue_id) > SYNC_QUEUE_WARN_THRESHOLD) {
+    log.warning("Detected slow task processing (sync_queue_len=%zd).\n", pending_tasks.size(sync_queue_id));
+  }
 }
 
 void ue_stack_lte::calc_tti_stats(const uint32_t duration_us)
@@ -319,11 +326,6 @@ void ue_stack_lte::calc_tti_stats(const uint32_t duration_us)
 
     proc_time.clear();
   }
-
-  // print warning if PHY pushes new TTI messages faster than we process them
-  if (pending_tasks.size(sync_queue_id) > SYNC_QUEUE_WARN_THRESHOLD) {
-    log.warning("Detected slow task processing (sync_queue_len=%zd).\n", pending_tasks.size(sync_queue_id));
-  }
 }
 
 /********************
diff --git a/srsue/ue.conf.example b/srsue/ue.conf.example
index 4ccc91b6b..1ef676c06 100644
--- a/srsue/ue.conf.example
+++ b/srsue/ue.conf.example
@@ -348,8 +348,11 @@ enable = false
 #
 # metrics_csv_filename: File path to use for CSV metrics.
 #
+# have_tti_time_stats:  Calculate TTI execution statistics using system clock
+#
 #####################################################################
 [general]
 #metrics_csv_enable  = false
 #metrics_period_secs = 1
 #metrics_csv_filename = /tmp/ue_metrics.csv
+#have_tti_time_stats = true
\ No newline at end of file