From ce42ae6ffd0429a764a3dd9e6afefeb5b1b541a7 Mon Sep 17 00:00:00 2001
From: Andrew Kryczka <andrewkr@fb.com>
Date: Tue, 7 Dec 2021 16:22:52 -0800
Subject: [PATCH] Fix Statistics in db_stress (#9260)

Summary:
The `Statistics` objects are meant to be shared across translation
units, but this was prevented by declaring them static. We need to
ensure they are defined once in the program. The effect is now
`StressTest::PrintStatistics()` can actually print statistics since it
now sees non-null values when `--statistics=1`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9260

Reviewed By: zhichao-cao

Differential Revision: D32910162

Pulled By: ajkr

fbshipit-source-id: c926d6f556177987bee5fa3cbc87597803b230ee
---
 TARGETS                          |  1 +
 db_stress_tool/CMakeLists.txt    |  1 +
 db_stress_tool/db_stress_stat.cc | 17 +++++++++++++++++
 db_stress_tool/db_stress_stat.h  |  5 +++--
 src.mk                           |  1 +
 5 files changed, 23 insertions(+), 2 deletions(-)
 create mode 100644 db_stress_tool/db_stress_stat.cc

diff --git a/TARGETS b/TARGETS
index 903d7e5f3..c33545cfd 100644
--- a/TARGETS
+++ b/TARGETS
@@ -871,6 +871,7 @@ cpp_library(
         "db_stress_tool/db_stress_gflags.cc",
         "db_stress_tool/db_stress_listener.cc",
         "db_stress_tool/db_stress_shared_state.cc",
+        "db_stress_tool/db_stress_stat.cc",
         "db_stress_tool/db_stress_test_base.cc",
         "db_stress_tool/db_stress_tool.cc",
         "db_stress_tool/expected_state.cc",
diff --git a/db_stress_tool/CMakeLists.txt b/db_stress_tool/CMakeLists.txt
index 68001967e..afbc5fa20 100644
--- a/db_stress_tool/CMakeLists.txt
+++ b/db_stress_tool/CMakeLists.txt
@@ -7,6 +7,7 @@ add_executable(db_stress${ARTIFACT_SUFFIX}
   db_stress_gflags.cc
   db_stress_listener.cc
   db_stress_shared_state.cc
+  db_stress_stat.cc
   db_stress_test_base.cc
   db_stress_tool.cc
   expected_state.cc
diff --git a/db_stress_tool/db_stress_stat.cc b/db_stress_tool/db_stress_stat.cc
new file mode 100644
index 000000000..6a7883a52
--- /dev/null
+++ b/db_stress_tool/db_stress_stat.cc
@@ -0,0 +1,17 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#ifdef GFLAGS
+
+#include "db_stress_tool/db_stress_stat.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats;
+std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats_secondaries;
+
+}  // namespace ROCKSDB_NAMESPACE
+
+#endif  // GFLAGS
diff --git a/db_stress_tool/db_stress_stat.h b/db_stress_tool/db_stress_stat.h
index 429cf3b2a..5b38c6e2b 100644
--- a/db_stress_tool/db_stress_stat.h
+++ b/db_stress_tool/db_stress_stat.h
@@ -21,9 +21,10 @@ DECLARE_bool(histogram);
 DECLARE_bool(progress_reports);
 
 namespace ROCKSDB_NAMESPACE {
+
 // Database statistics
-static std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats;
-static std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats_secondaries;
+extern std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats;
+extern std::shared_ptr<ROCKSDB_NAMESPACE::Statistics> dbstats_secondaries;
 
 class Stats {
  private:
diff --git a/src.mk b/src.mk
index 12718c66b..f53a417ba 100644
--- a/src.mk
+++ b/src.mk
@@ -349,6 +349,7 @@ STRESS_LIB_SOURCES =                                            \
   db_stress_tool/db_stress_gflags.cc                           \
   db_stress_tool/db_stress_listener.cc                         \
   db_stress_tool/db_stress_shared_state.cc                     \
+  db_stress_tool/db_stress_stat.cc                             \
   db_stress_tool/db_stress_test_base.cc                        \
   db_stress_tool/db_stress_tool.cc                             \
   db_stress_tool/expected_state.cc                             \