[PATCH] NTP: ntp-helper functions

This patch cleans up a commonly repeated set of changes to the NTP state
variables by adding two helper inline functions:

ntp_clear(): Clears the ntp state variables

ntp_synced(): Returns 1 if the system is synced with a time server.

This was compile tested for alpha, arm, i386, x86-64, ppc64, s390, sparc,
sparc64.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/include/linux/timex.h b/include/linux/timex.h
index 74fdd07d3792..7e050a2cc35b 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -260,6 +260,29 @@ extern long pps_calcnt;		/* calibration intervals */
 extern long pps_errcnt;         /* calibration errors */
 extern long pps_stbcnt;         /* stability limit exceeded */
 
+/**
+ * ntp_clear - Clears the NTP state variables
+ *
+ * Must be called while holding a write on the xtime_lock
+ */
+static inline void ntp_clear(void)
+{
+        time_adjust = 0;                /* stop active adjtime() */
+        time_status |= STA_UNSYNC;
+        time_maxerror = NTP_PHASE_LIMIT;
+        time_esterror = NTP_PHASE_LIMIT;
+}
+
+/**
+ * ntp_synced - Returns 1 if the NTP status is not UNSYNC
+ *
+ */
+static inline int ntp_synced(void)
+{
+        return !(time_status & STA_UNSYNC);
+}
+
+
 #ifdef CONFIG_TIME_INTERPOLATION
 
 #define TIME_SOURCE_CPU 0