From f26f127183f6e9e5d6b86f5f8dc9420e514ada6c Mon Sep 17 00:00:00 2001
From: Martin Duffy <martin.duffy@kitware.com>
Date: Mon, 9 Jun 2025 11:06:02 -0400
Subject: instrumentation: Reuse single cmsys::SystemInformation

---
 Source/cmInstrumentation.cxx | 49 ++++++++++++++++++++++++++------------------
 Source/cmInstrumentation.h   | 24 +++++++++++++++-------
 2 files changed, 46 insertions(+), 27 deletions(-)

diff --git a/Source/cmInstrumentation.cxx b/Source/cmInstrumentation.cxx
index 3d743dc..5ff709d 100644
--- a/Source/cmInstrumentation.cxx
+++ b/Source/cmInstrumentation.cxx
@@ -3,11 +3,11 @@
 #include <chrono>
 #include <ctime>
 #include <iomanip>
-#include <memory>
 #include <set>
 #include <sstream>
 #include <utility>
 
+#include <cm/memory>
 #include <cm/optional>
 
 #include <cm3p/json/writer.h>
@@ -126,6 +126,14 @@ void cmInstrumentation::LoadQueries()
   }
 }
 
+cmsys::SystemInformation& cmInstrumentation::GetSystemInformation()
+{
+  if (!this->systemInformation) {
+    this->systemInformation = cm::make_unique<cmsys::SystemInformation>();
+  }
+  return *this->systemInformation;
+}
+
 bool cmInstrumentation::ReadJSONQueries(std::string const& directory)
 {
   cmsys::Directory d;
@@ -210,8 +218,7 @@ bool cmInstrumentation::HasPreOrPostBuildHook() const
 int cmInstrumentation::CollectTimingData(cmInstrumentationQuery::Hook hook)
 {
   // Don't run collection if hook is disabled
-  if (hook != cmInstrumentationQuery::Hook::Manual &&
-      this->hooks.find(hook) == this->hooks.end()) {
+  if (hook != cmInstrumentationQuery::Hook::Manual && !this->HasHook(hook)) {
     return 0;
   }
 
@@ -299,36 +306,38 @@ int cmInstrumentation::CollectTimingData(cmInstrumentationQuery::Hook hook)
 void cmInstrumentation::InsertDynamicSystemInformation(
   Json::Value& root, std::string const& prefix)
 {
-  cmsys::SystemInformation info;
   Json::Value data;
-  info.RunCPUCheck();
-  info.RunMemoryCheck();
+  double memory;
+  double load;
+  this->GetDynamicSystemInformation(memory, load);
   if (!root.isMember("dynamicSystemInformation")) {
     root["dynamicSystemInformation"] = Json::objectValue;
   }
   root["dynamicSystemInformation"][cmStrCat(prefix, "HostMemoryUsed")] =
-    (double)info.GetHostMemoryUsed();
-  root["dynamicSystemInformation"][cmStrCat(prefix, "CPULoadAverage")] =
-    info.GetLoadAverage();
+    memory;
+  root["dynamicSystemInformation"][cmStrCat(prefix, "CPULoadAverage")] = load;
 }
 
 void cmInstrumentation::GetDynamicSystemInformation(double& memory,
                                                     double& load)
 {
-  cmsys::SystemInformation info;
-  Json::Value data;
-  info.RunCPUCheck();
-  info.RunMemoryCheck();
+  cmsys::SystemInformation& info = this->GetSystemInformation();
+  if (!this->ranSystemChecks) {
+    info.RunCPUCheck();
+    info.RunMemoryCheck();
+    this->ranSystemChecks = true;
+  }
   memory = (double)info.GetHostMemoryUsed();
   load = info.GetLoadAverage();
 }
 
 void cmInstrumentation::InsertStaticSystemInformation(Json::Value& root)
 {
-  cmsys::SystemInformation info;
-  info.RunCPUCheck();
-  info.RunOSCheck();
-  info.RunMemoryCheck();
+  cmsys::SystemInformation& info = this->GetSystemInformation();
+  if (!this->ranOSCheck) {
+    info.RunOSCheck();
+    this->ranOSCheck = true;
+  }
   Json::Value infoRoot;
   infoRoot["familyId"] = info.GetFamilyID();
   infoRoot["hostname"] = info.GetHostname();
@@ -408,7 +417,7 @@ std::string cmInstrumentation::InstrumentTest(
     this->InsertDynamicSystemInformation(root, "after");
   }
 
-  cmsys::SystemInformation info;
+  cmsys::SystemInformation& info = this->GetSystemInformation();
   std::string file_name = cmStrCat(
     "test-",
     this->ComputeSuffixHash(cmStrCat(command_str, info.GetProcessId())),
@@ -468,7 +477,7 @@ int cmInstrumentation::InstrumentCommand(
   // Exit early if configure didn't generate a query
   if (reloadQueriesAfterCommand) {
     this->LoadQueries();
-    if (!this->hasQuery) {
+    if (!this->HasQuery()) {
       return ret;
     }
     if (this->HasQuery(
@@ -530,7 +539,7 @@ int cmInstrumentation::InstrumentCommand(
   root["workingDir"] = cmSystemTools::GetLogicalWorkingDirectory();
 
   // Write Json
-  cmsys::SystemInformation info;
+  cmsys::SystemInformation& info = this->GetSystemInformation();
   std::string const& file_name = cmStrCat(
     command_type, "-",
     this->ComputeSuffixHash(cmStrCat(command_str, info.GetProcessId())),
diff --git a/Source/cmInstrumentation.h b/Source/cmInstrumentation.h
index b044885..aeec33b 100644
--- a/Source/cmInstrumentation.h
+++ b/Source/cmInstrumentation.h
@@ -11,9 +11,13 @@
 #include <string>
 #include <vector>
 
+#include <cm/memory>
 #include <cm/optional>
 
 #include <cm3p/json/value.h>
+#ifndef CMAKE_BOOTSTRAP
+#  include <cmsys/SystemInformation.hxx>
+#endif
 #include <stdint.h>
 
 #include "cmInstrumentationQuery.h"
@@ -60,13 +64,13 @@ private:
   void WriteInstrumentationJson(Json::Value& index,
                                 std::string const& directory,
                                 std::string const& file_name);
-  static void InsertStaticSystemInformation(Json::Value& index);
-  static void GetDynamicSystemInformation(double& memory, double& load);
-  static void InsertDynamicSystemInformation(Json::Value& index,
-                                             std::string const& instant);
-  static void InsertTimingData(
-    Json::Value& root, std::chrono::steady_clock::time_point steadyStart,
-    std::chrono::system_clock::time_point systemStart);
+  void InsertStaticSystemInformation(Json::Value& index);
+  void GetDynamicSystemInformation(double& memory, double& load);
+  void InsertDynamicSystemInformation(Json::Value& index,
+                                      std::string const& instant);
+  void InsertTimingData(Json::Value& root,
+                        std::chrono::steady_clock::time_point steadyStart,
+                        std::chrono::system_clock::time_point systemStart);
   bool HasQueryFile(std::string const& file);
   static std::string GetCommandStr(std::vector<std::string> const& args);
   static std::string ComputeSuffixHash(std::string const& command_str);
@@ -84,4 +88,10 @@ private:
   std::map<std::string, std::string> cdashSnippetsMap;
   Json::Value preTestStats;
   bool hasQuery = false;
+  bool ranSystemChecks = false;
+  bool ranOSCheck = false;
+#ifndef CMAKE_BOOTSTRAP
+  std::unique_ptr<cmsys::SystemInformation> systemInformation;
+  cmsys::SystemInformation& GetSystemInformation();
+#endif
 };
-- 
cgit v0.12