From a51f2a1de475b8ecec8acfdb5da58426ea833f30 Mon Sep 17 00:00:00 2001
From: Alejandro Leal Conejos <alejandro.leal@srs.io>
Date: Mon, 7 Jun 2021 15:10:04 +0200
Subject: [PATCH] Fills the value of the number of cpus for the
 system_metrics_t and initiliaze its value to 0 when executing 2 measures in
 less than 100 ms.

---
 lib/include/srsran/system/sys_metrics.h | 17 +++++++++--------
 lib/src/system/sys_metrics_processor.cc | 16 +++++++++++++++-
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/lib/include/srsran/system/sys_metrics.h b/lib/include/srsran/system/sys_metrics.h
index fb05aa2c3..92baba422 100644
--- a/lib/include/srsran/system/sys_metrics.h
+++ b/lib/include/srsran/system/sys_metrics.h
@@ -13,6 +13,7 @@
 #ifndef SRSRAN_SYS_METRICS_H
 #define SRSRAN_SYS_METRICS_H
 
+#include <array>
 #include <cstdint>
 
 namespace srsran {
@@ -21,14 +22,14 @@ constexpr uint32_t metrics_max_supported_cpu = 32u;
 
 /// Metrics of cpu usage, memory consumption and number of thread used by the process.
 struct sys_metrics_t {
-  uint32_t process_realmem_kB    = 0;
-  uint32_t process_virtualmem_kB = 0;
-  float    process_realmem       = 0.f;
-  uint32_t thread_count          = 0;
-  float    process_cpu_usage     = 0.f;
-  float    system_mem            = 0.f;
-  uint32_t cpu_count             = 0;
-  float    cpu_load[metrics_max_supported_cpu];
+  uint32_t                                     process_realmem_kB    = 0;
+  uint32_t                                     process_virtualmem_kB = 0;
+  float                                        process_realmem       = 0.f;
+  uint32_t                                     thread_count          = 0;
+  float                                        process_cpu_usage     = 0.f;
+  float                                        system_mem            = 0.f;
+  uint32_t                                     cpu_count             = 0;
+  std::array<float, metrics_max_supported_cpu> cpu_load;
 };
 
 } // namespace srsran
diff --git a/lib/src/system/sys_metrics_processor.cc b/lib/src/system/sys_metrics_processor.cc
index 408027c6b..d5d616cf6 100644
--- a/lib/src/system/sys_metrics_processor.cc
+++ b/lib/src/system/sys_metrics_processor.cc
@@ -49,6 +49,20 @@ sys_metrics_processor::proc_stats_info::proc_stats_info()
       arg_end >> env_start >> env_end >> exit_code;
 }
 
+/// Returns a null sys_metrics_t with the cpu count field filled.
+static sys_metrics_t create_null_metrics()
+{
+  sys_metrics_t metrics;
+
+  if (cpu_count > metrics_max_supported_cpu) {
+    return metrics;
+  }
+
+  metrics.cpu_count = cpu_count;
+  metrics.cpu_load.fill(0.f);
+  return metrics;
+}
+
 sys_metrics_t sys_metrics_processor::get_metrics()
 {
   auto     current_time = std::chrono::steady_clock::now();
@@ -58,7 +72,7 @@ sys_metrics_t sys_metrics_processor::get_metrics()
   // The time elapsed between 2 measures must be greater that 100 milliseconds.
   if (measure_interval_ms < 100u) {
     logger.warning("Interval less than 100ms, skipping measurement.");
-    return {};
+    return create_null_metrics();
   }
 
   sys_metrics_t metrics;