revert support for monotonic clock - it is not faster than realtime

include/spdlog/details/os.h

@@ -35,20 +35,6 @@ namespace details
 namespace os
 {
 
-#if defined __linux__ && defined SPDLOG_CLOCK_MONOTONIC
-inline uint64_t clock_offset()
-{
-    timespec ts_realtime;
-    ::clock_gettime(CLOCK_REALTIME, &ts_realtime);
-    timespec ts_monotonic;
-    ::clock_gettime(CLOCK_MONOTONIC, &ts_monotonic);
-
-    const uint64_t realtime = ts_realtime.tv_sec * 1000000000 + ts_realtime.tv_nsec;
-    const uint64_t monotonic = ts_monotonic.tv_sec * 1000000000 + ts_monotonic.tv_nsec;
-    return realtime - monotonic;
-}
-#endif
-
 inline spdlog::log_clock::time_point now()
 {
 
@@ -59,14 +45,7 @@ inline spdlog::log_clock::time_point now()
                std::chrono::duration_cast<typename log_clock::duration>(
                    std::chrono::seconds(ts.tv_sec) + std::chrono::nanoseconds(ts.tv_nsec)));
 
-#elif defined __linux__ && defined SPDLOG_CLOCK_MONOTONIC
-    static const auto offset = std::chrono::nanoseconds(clock_offset());
 
-    timespec ts;
-    ::clock_gettime(CLOCK_MONOTONIC, &ts);
-    return std::chrono::time_point<log_clock, typename log_clock::duration>(
-               std::chrono::duration_cast<typename log_clock::duration>(
-                   offset + std::chrono::seconds(ts.tv_sec) + std::chrono::nanoseconds(ts.tv_nsec)));
 #else
     return log_clock::now();
 #endif

include/spdlog/tweakme.h

@@ -17,14 +17,6 @@
 ///////////////////////////////////////////////////////////////////////////////
 
 
-///////////////////////////////////////////////////////////////////////////////
-// Under Linux, the much faster CLOCK_MONOTONIC clock can be used.
-// This clock is more accurate than CLOCK_REALTIME_COARSE and faster than regular clock.
-// Uncomment to use it instead of the regular clock.
-// #define SPDLOG_CLOCK_MONOTONIC
-///////////////////////////////////////////////////////////////////////////////
-
-
 ///////////////////////////////////////////////////////////////////////////////
 // Uncomment if date/time logging is not needed.
 // This will prevent spdlog from quering the clock on each log call.