From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Mon, 18 Aug 2014 11:06:38 +0000 (+0200)
Subject: rtc: improve accuracy of preinit step
X-Git-Tag: 1.31-pre1~16
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=38ac08111410e5d3f8e0f1e6b699809b149a488a;p=thirdparty%2Fchrony.git

rtc: improve accuracy of preinit step
---

diff --git a/rtc_linux.c b/rtc_linux.c
index c0c8a69e..64d41992 100644
--- a/rtc_linux.c
+++ b/rtc_linux.c
@@ -1027,8 +1027,12 @@ RTC_Linux_TimePreInit(void)
       }
 
       /* Correct time */
-      new_sys_time.tv_sec = rtc_t - (time_t)(0.5 + accumulated_error);
-      new_sys_time.tv_usec = 0;
+
+      new_sys_time.tv_sec = rtc_t;
+      /* Average error in the RTC reading */
+      new_sys_time.tv_usec = 500000;
+
+      UTI_AddDoubleToTimeval(&new_sys_time, -accumulated_error, &new_sys_time);
 
       /* Set system time only if the step is larger than 1 second */
       if (!(gettimeofday(&old_sys_time, NULL) < 0) &&