diff --git a/src/timedata.cpp b/src/timedata.cpp
index d346070d0..2c71247ae 100644
--- a/src/timedata.cpp
+++ b/src/timedata.cpp
@@ -1,127 +1,127 @@
 // Copyright (c) 2014-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <timedata.h>
 
 #include <netaddress.h>
 #include <node/ui_interface.h>
 #include <sync.h>
 #include <util/system.h>
 #include <util/translation.h>
 #include <warnings.h>
 
-static RecursiveMutex cs_nTimeOffset;
-static int64_t nTimeOffset GUARDED_BY(cs_nTimeOffset) = 0;
+static Mutex g_timeoffset_mutex;
+static int64_t nTimeOffset GUARDED_BY(g_timeoffset_mutex) = 0;
 
 /**
  * "Never go to sea with two chronometers; take one or three."
  * Our three time sources are:
  *  - System clock
  *  - Median of other nodes clocks
  *  - The user (asking the user to fix the system clock if the first two
  * disagree)
  */
 int64_t GetTimeOffset() {
-    LOCK(cs_nTimeOffset);
+    LOCK(g_timeoffset_mutex);
     return nTimeOffset;
 }
 
 int64_t GetAdjustedTime() {
     return GetTime() + GetTimeOffset();
 }
 
 static uint64_t abs64(int64_t n) {
     const uint64_t un = n;
     return (n >= 0) ? un : -un;
 }
 
 #define BITCOIN_TIMEDATA_MAX_SAMPLES 200
 
 void AddTimeData(const CNetAddr &ip, int64_t nOffsetSample) {
-    LOCK(cs_nTimeOffset);
+    LOCK(g_timeoffset_mutex);
     // Ignore duplicates
     static std::set<CNetAddr> setKnown;
     if (setKnown.size() == BITCOIN_TIMEDATA_MAX_SAMPLES) {
         return;
     }
     if (!setKnown.insert(ip).second) {
         return;
     }
 
     // Add data
     static CMedianFilter<int64_t> vTimeOffsets(BITCOIN_TIMEDATA_MAX_SAMPLES, 0);
     vTimeOffsets.input(nOffsetSample);
     LogPrint(BCLog::NET,
              "added time data, samples %d, offset %+d (%+d minutes)\n",
              vTimeOffsets.size(), nOffsetSample, nOffsetSample / 60);
 
     // There is a known issue here (see issue #4521):
     //
     // - The structure vTimeOffsets contains up to 200 elements, after which any
     // new element added to it will not increase its size, replacing the oldest
     // element.
     //
     // - The condition to update nTimeOffset includes checking whether the
     // number of elements in vTimeOffsets is odd, which will never happen after
     // there are 200 elements.
     //
     // But in this case the 'bug' is protective against some attacks, and may
     // actually explain why we've never seen attacks which manipulate the clock
     // offset.
     //
     // So we should hold off on fixing this and clean it up as part of a timing
     // cleanup that strengthens it in a number of other ways.
     //
     if (vTimeOffsets.size() >= 5 && vTimeOffsets.size() % 2 == 1) {
         int64_t nMedian = vTimeOffsets.median();
         std::vector<int64_t> vSorted = vTimeOffsets.sorted();
         // Only let other nodes change our time by so much
         if (abs64(nMedian) <=
             uint64_t(std::max<int64_t>(
                 0, gArgs.GetArg("-maxtimeadjustment",
                                 DEFAULT_MAX_TIME_ADJUSTMENT)))) {
             nTimeOffset = nMedian;
         } else {
             nTimeOffset = 0;
 
             static bool fDone;
             if (!fDone) {
                 // If nobody has a time different than ours but within 5 minutes
                 // of ours, give a warning
                 bool fMatch = false;
                 for (const int64_t nOffset : vSorted) {
                     if (nOffset != 0 && abs64(nOffset) < 5 * 60) {
                         fMatch = true;
                     }
                 }
 
                 if (!fMatch) {
                     fDone = true;
                     bilingual_str strMessage =
                         strprintf(_("Please check that your computer's date "
                                     "and time are correct! If your clock is "
                                     "wrong, %s will not work properly."),
                                   PACKAGE_NAME);
                     SetMiscWarning(strMessage.translated);
                     uiInterface.ThreadSafeMessageBox(
                         strMessage, "", CClientUIInterface::MSG_WARNING);
                 }
             }
         }
 
         if (LogAcceptCategory(BCLog::NET)) {
             for (const int64_t n : vSorted) {
                 LogPrintToBeContinued(BCLog::NET, "%+d  ", n);
             }
 
             LogPrintToBeContinued(BCLog::NET, "|  ");
             LogPrint(BCLog::NET, "nTimeOffset = %+d  (%+d minutes)\n",
                      nTimeOffset, nTimeOffset / 60);
         }
     }
 }