From 57a95a700155345c658936a3b2ca492f36192691 Mon Sep 17 00:00:00 2001
From: Tomas Kolda <koldat@gmail.com>
Date: Wed, 27 Jan 2016 21:00:42 +0100
Subject: [PATCH] Making use of GetSystemTimePreciseAsFileTime dynamic - code
 review fixes

---
 db/auto_roll_logger.cc |  4 +++-
 port/win/env_win.cc    | 20 +++++++-------------
 2 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/db/auto_roll_logger.cc b/db/auto_roll_logger.cc
index c984b4810b..b8ba14c834 100644
--- a/db/auto_roll_logger.cc
+++ b/db/auto_roll_logger.cc
@@ -32,9 +32,11 @@ Status AutoRollLogger::ResetLogger() {
 }
 
 void AutoRollLogger::RollLogFile() {
+  // This function is called when log is rotating. Two rotations
+  // can happen quickly (NowMicro returns same value). To not overwrite
+  // previous log file we increment by one micro second and try again.
   uint64_t now = env_->NowMicros();
   std::string old_fname;
-  // Try to check target name only 10 times at most
   for (int i = 0; i < 10; i++) {
     old_fname = OldInfoLogFileName(
       dbname_, now, db_absolute_path_, db_log_dir_);
diff --git a/port/win/env_win.cc b/port/win/env_win.cc
index 87a25569c8..1ae0b19326 100644
--- a/port/win/env_win.cc
+++ b/port/win/env_win.cc
@@ -2110,28 +2110,22 @@ class WinEnv : public Env {
   std::vector<ThreadPool> thread_pools_;
   mutable std::mutex mu_;
   std::vector<std::thread> threads_to_join_;
-  static FnGetSystemTimePreciseAsFileTime GetSystemTimePreciseAsFileTime_;
-  static bool GetSystemTimePreciseAsFileTimeInitialized_;
+  FnGetSystemTimePreciseAsFileTime GetSystemTimePreciseAsFileTime_;
 };
 
-FnGetSystemTimePreciseAsFileTime WinEnv::GetSystemTimePreciseAsFileTime_ = NULL;
-bool WinEnv::GetSystemTimePreciseAsFileTimeInitialized_ = false;
-
 WinEnv::WinEnv()
     : checkedDiskForMmap_(false),
       forceMmapOff(false),
       page_size_(4 * 1012),
       allocation_granularity_(page_size_),
       perf_counter_frequency_(0),
-      thread_pools_(Priority::TOTAL) {
+      thread_pools_(Priority::TOTAL),
+      GetSystemTimePreciseAsFileTime_(NULL) {
 
-  if (!GetSystemTimePreciseAsFileTimeInitialized_) {
-    HMODULE module = GetModuleHandle("kernel32.dll");
-    if (module != NULL) {
-      GetSystemTimePreciseAsFileTime_ = (FnGetSystemTimePreciseAsFileTime)GetProcAddress(
-        module, "GetSystemTimePreciseAsFileTime");
-    }
-    GetSystemTimePreciseAsFileTimeInitialized_ = true;
+  HMODULE module = GetModuleHandle("kernel32.dll");
+  if (module != NULL) {
+    GetSystemTimePreciseAsFileTime_ = (FnGetSystemTimePreciseAsFileTime)GetProcAddress(
+      module, "GetSystemTimePreciseAsFileTime");
   }
 
   SYSTEM_INFO sinfo;