From fdcedf7b75808dd72c3cc0b931be11b04d75c60a Mon Sep 17 00:00:00 2001
From: john stultz <johnstul@us.ibm.com>
Date: Wed, 18 Feb 2009 16:02:22 -0800
Subject: time: apply NTP frequency/tick changes immediately

Since the GENERIC_TIME changes landed, the adjtimex behavior changed
for struct timex.tick and .freq changed. When the tick or freq value
is set, we adjust the tick_length_base in ntp_update_frequency().
However, this new value doesn't get applied to tick_length until the
next second (via second_overflow).

This means some applications that do quick time tweaking do not see the
requested change made as quickly as expected.

I've run a few tests with this change, and ntpd still functions fine.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 7 +++++++
 1 file changed, 7 insertions(+)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index f5f793d9241..e1fa3689a90 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -51,6 +51,7 @@ static long ntp_tick_adj;
 
 static void ntp_update_frequency(void)
 {
+	u64 old_tick_length_base = tick_length_base;
 	u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
 				<< NTP_SCALE_SHIFT;
 	second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
@@ -60,6 +61,12 @@ static void ntp_update_frequency(void)
 
 	tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
 	tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
+
+	/*
+	 * Don't wait for the next second_overflow, apply
+	 * the change to the tick length immediately
+	 */
+	tick_length += tick_length_base - old_tick_length_base;
 }
 
 static void ntp_update_offset(long offset)
-- 
cgit v1.2.3


From 53bbfa9e9437e70b322368e82c723112d690e304 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Wed, 20 Feb 2008 07:58:42 +0100
Subject: time: ntp: clean up kernel/time/ntp.c

Impact: cleanup, no functionality changed

Make this file a bit more readable by applying a consistent coding style.

No code changed:

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2552	    170	    168	   2890	    b4a	ntp.o.before
   2552	    170	    168	   2890	    b4a	ntp.o.after

md5:
   eae1275df0b7d6290c13f6f6f8f05c8c  ntp.o.before.asm
   eae1275df0b7d6290c13f6f6f8f05c8c  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 129 ++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 81 insertions(+), 48 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index e1fa3689a90..3479ec48e60 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -1,53 +1,81 @@
 /*
- * linux/kernel/time/ntp.c
- *
  * NTP state machine interfaces and logic.
  *
  * This code was mainly moved from kernel/timer.c and kernel/time.c
  * Please see those files for relevant copyright info and historical
  * changelogs.
  */
-
-#include <linux/mm.h>
-#include <linux/time.h>
-#include <linux/timex.h>
-#include <linux/jiffies.h>
-#include <linux/hrtimer.h>
 #include <linux/capability.h>
-#include <linux/math64.h>
 #include <linux/clocksource.h>
 #include <linux/workqueue.h>
-#include <asm/timex.h>
+#include <linux/hrtimer.h>
+#include <linux/jiffies.h>
+#include <linux/math64.h>
+#include <linux/timex.h>
+#include <linux/time.h>
+#include <linux/mm.h>
 
 /*
- * Timekeeping variables
+ * NTP timekeeping variables:
  */
-unsigned long tick_usec = TICK_USEC; 		/* USER_HZ period (usec) */
-unsigned long tick_nsec;			/* ACTHZ period (nsec) */
-u64 tick_length;
-static u64 tick_length_base;
 
-static struct hrtimer leap_timer;
+/* USER_HZ period (usecs): */
+unsigned long			tick_usec = TICK_USEC;
+
+/* ACTHZ period (nsecs): */
+unsigned long			tick_nsec;
 
-#define MAX_TICKADJ		500		/* microsecs */
-#define MAX_TICKADJ_SCALED	(((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \
-				  NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
+u64				tick_length;
+static u64			tick_length_base;
+
+static struct hrtimer		leap_timer;
+
+#define MAX_TICKADJ		500		/* usecs */
+#define MAX_TICKADJ_SCALED \
+  (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
 
 /*
  * phase-lock loop variables
  */
-/* TIME_ERROR prevents overwriting the CMOS clock */
-static int time_state = TIME_OK;	/* clock synchronization status	*/
-int time_status = STA_UNSYNC;		/* clock status bits		*/
-static long time_tai;			/* TAI offset (s)		*/
-static s64 time_offset;			/* time adjustment (ns)		*/
-static long time_constant = 2;		/* pll time constant		*/
-long time_maxerror = NTP_PHASE_LIMIT;	/* maximum error (us)		*/
-long time_esterror = NTP_PHASE_LIMIT;	/* estimated error (us)		*/
-static s64 time_freq;			/* frequency offset (scaled ns/s)*/
-static long time_reftime;		/* time at last adjustment (s)	*/
-long time_adjust;
-static long ntp_tick_adj;
+
+/*
+ * clock synchronization status
+ *
+ * (TIME_ERROR prevents overwriting the CMOS clock)
+ */
+static int			time_state = TIME_OK;
+
+/* clock status bits:							*/
+int				time_status = STA_UNSYNC;
+
+/* TAI offset (secs):							*/
+static long			time_tai;
+
+/* time adjustment (nsecs):						*/
+static s64			time_offset;
+
+/* pll time constant:							*/
+static long			time_constant = 2;
+
+/* maximum error (usecs):						*/
+long				time_maxerror = NTP_PHASE_LIMIT;
+
+/* estimated error (usecs):						*/
+long				time_esterror = NTP_PHASE_LIMIT;
+
+/* frequency offset (scaled nsecs/secs):				*/
+static s64			time_freq;
+
+/* time at last adjustment (secs):					*/
+static long			time_reftime;
+
+long				time_adjust;
+
+static long			ntp_tick_adj;
+
+/*
+ * NTP methods:
+ */
 
 static void ntp_update_frequency(void)
 {
@@ -118,15 +146,15 @@ static void ntp_update_offset(long offset)
  */
 void ntp_clear(void)
 {
-	time_adjust = 0;		/* stop active adjtime() */
-	time_status |= STA_UNSYNC;
-	time_maxerror = NTP_PHASE_LIMIT;
-	time_esterror = NTP_PHASE_LIMIT;
+	time_adjust	= 0;		/* stop active adjtime() */
+	time_status	|= STA_UNSYNC;
+	time_maxerror	= NTP_PHASE_LIMIT;
+	time_esterror	= NTP_PHASE_LIMIT;
 
 	ntp_update_frequency();
 
-	tick_length = tick_length_base;
-	time_offset = 0;
+	tick_length	= tick_length_base;
+	time_offset	= 0;
 }
 
 /*
@@ -147,8 +175,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 		xtime.tv_sec--;
 		wall_to_monotonic.tv_sec++;
 		time_state = TIME_OOP;
-		printk(KERN_NOTICE "Clock: "
-		       "inserting leap second 23:59:60 UTC\n");
+		printk(KERN_NOTICE
+			"Clock: inserting leap second 23:59:60 UTC\n");
 		hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC);
 		res = HRTIMER_RESTART;
 		break;
@@ -157,8 +185,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
 		time_tai--;
 		wall_to_monotonic.tv_sec--;
 		time_state = TIME_WAIT;
-		printk(KERN_NOTICE "Clock: "
-		       "deleting leap second 23:59:59 UTC\n");
+		printk(KERN_NOTICE
+			"Clock: deleting leap second 23:59:59 UTC\n");
 		break;
 	case TIME_OOP:
 		time_tai++;
@@ -199,10 +227,10 @@ void second_overflow(void)
 	 * Compute the phase adjustment for the next second. The offset is
 	 * reduced by a fixed factor times the time constant.
 	 */
-	tick_length = tick_length_base;
-	time_adj = shift_right(time_offset, SHIFT_PLL + time_constant);
-	time_offset -= time_adj;
-	tick_length += time_adj;
+	tick_length	= tick_length_base;
+	time_adj	= shift_right(time_offset, SHIFT_PLL + time_constant);
+	time_offset	-= time_adj;
+	tick_length	+= time_adj;
 
 	if (unlikely(time_adjust)) {
 		if (time_adjust > MAX_TICKADJ) {
@@ -240,12 +268,13 @@ static void sync_cmos_clock(struct work_struct *work)
 	 * This code is run on a timer.  If the clock is set, that timer
 	 * may not expire at the correct time.  Thus, we adjust...
 	 */
-	if (!ntp_synced())
+	if (!ntp_synced()) {
 		/*
 		 * Not synced, exit, do not restart a timer (if one is
 		 * running, let it run out).
 		 */
 		return;
+	}
 
 	getnstimeofday(&now);
 	if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
@@ -277,7 +306,8 @@ static void notify_cmos_timer(void)
 static inline void notify_cmos_timer(void) { }
 #endif
 
-/* adjtimex mainly allows reading (and writing, if superuser) of
+/*
+ * adjtimex mainly allows reading (and writing, if superuser) of
  * kernel time-keeping variables. used by xntpd.
  */
 int do_adjtimex(struct timex *txc)
@@ -298,7 +328,10 @@ int do_adjtimex(struct timex *txc)
 		 if (txc->modes && !capable(CAP_SYS_TIME))
 			return -EPERM;
 
-		/* if the quartz is off by more than 10% something is VERY wrong! */
+		/*
+		 * if the quartz is off by more than 10% then
+		 * something is VERY wrong!
+		 */
 		if (txc->modes & ADJ_TICK &&
 		    (txc->tick <  900000/USER_HZ ||
 		     txc->tick > 1100000/USER_HZ))
-- 
cgit v1.2.3


From 3c972c2444dcb7088999c32b8c5a7ab3b8a6c0b6 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 12:06:57 +0100
Subject: time: ntp: simplify the second_overflow() code flow

Impact: cleanup, no functionality changed

Instead of a hierarchy of conditions, transform them to clean
gradual conditions and return's.

This makes the flow easier to read and makes the purpose of
the function easier to understand.

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2552	    170	    168	   2890	    b4a	ntp.o.before
   2552	    170	    168	   2890	    b4a	ntp.o.after

md5:
   eae1275df0b7d6290c13f6f6f8f05c8c  ntp.o.before.asm
   eae1275df0b7d6290c13f6f6f8f05c8c  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 3479ec48e60..1fa6615b317 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -232,19 +232,24 @@ void second_overflow(void)
 	time_offset	-= time_adj;
 	tick_length	+= time_adj;
 
-	if (unlikely(time_adjust)) {
-		if (time_adjust > MAX_TICKADJ) {
-			time_adjust -= MAX_TICKADJ;
-			tick_length += MAX_TICKADJ_SCALED;
-		} else if (time_adjust < -MAX_TICKADJ) {
-			time_adjust += MAX_TICKADJ;
-			tick_length -= MAX_TICKADJ_SCALED;
-		} else {
-			tick_length += (s64)(time_adjust * NSEC_PER_USEC /
-					NTP_INTERVAL_FREQ) << NTP_SCALE_SHIFT;
-			time_adjust = 0;
-		}
+	if (!time_adjust)
+		return;
+
+	if (time_adjust > MAX_TICKADJ) {
+		time_adjust -= MAX_TICKADJ;
+		tick_length += MAX_TICKADJ_SCALED;
+		return;
 	}
+
+	if (time_adjust < -MAX_TICKADJ) {
+		time_adjust += MAX_TICKADJ;
+		tick_length -= MAX_TICKADJ_SCALED;
+		return;
+	}
+
+	tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
+							 << NTP_SCALE_SHIFT;
+	time_adjust = 0;
 }
 
 #ifdef CONFIG_GENERIC_CMOS_UPDATE
-- 
cgit v1.2.3


From bbd1267690bb6940d0722dd33e929442c0409c01 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 12:11:11 +0100
Subject: time: ntp: simplify the MAX_TICKADJ_SCALED definition

Impact: cleanup, no functionality changed

There's an ugly u64 typecase in the MAX_TICKADJ_SCALED definition,
this can be eliminated by making the MAX_TICKADJ constant's type
64-bit (signed).

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2504	    114	    136	   2754	    ac2	ntp.o.before
   2504	    114	    136	   2754	    ac2	ntp.o.after

md5:
   41f3009debc9b397d7394dd77d912f0a  ntp.o.before.asm
   41f3009debc9b397d7394dd77d912f0a  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 1fa6615b317..2b758c935c6 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -30,9 +30,9 @@ static u64			tick_length_base;
 
 static struct hrtimer		leap_timer;
 
-#define MAX_TICKADJ		500		/* usecs */
+#define MAX_TICKADJ		500LL		/* usecs */
 #define MAX_TICKADJ_SCALED \
-  (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
+	(((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
 
 /*
  * phase-lock loop variables
-- 
cgit v1.2.3


From 9ce616aaefcb9309cb9c49a36310ebda6061b98b Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 12:42:59 +0100
Subject: time: ntp: clean up ntp_update_frequency()

Impact: cleanup, no functionality changed

Prepare a refactoring of ntp_update_frequency().

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2504	    114	    136	   2754	    ac2	ntp.o.before
   2504	    114	    136	   2754	    ac2	ntp.o.after

md5:
   41f3009debc9b397d7394dd77d912f0a  ntp.o.before.asm
   41f3009debc9b397d7394dd77d912f0a  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 2b758c935c6..7d281d9fbe3 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -77,24 +77,33 @@ static long			ntp_tick_adj;
  * NTP methods:
  */
 
+/*
+ * Update (tick_length, tick_length_base, tick_nsec), based
+ * on (tick_usec, ntp_tick_adj, time_freq):
+ */
 static void ntp_update_frequency(void)
 {
-	u64 old_tick_length_base = tick_length_base;
-	u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
-				<< NTP_SCALE_SHIFT;
-	second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
-	second_length += time_freq;
+	u64 prev_base;
+	u64 second_length;
+
+	prev_base = tick_length_base;
+
+	second_length		 = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
+						<< NTP_SCALE_SHIFT;
+
+	second_length		+= (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
+	second_length		+= time_freq;
 
-	tick_length_base = second_length;
+	tick_length_base	 = second_length;
 
-	tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
-	tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
+	tick_nsec		 = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
+	tick_length_base	 = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
 
 	/*
 	 * Don't wait for the next second_overflow, apply
 	 * the change to the tick length immediately
 	 */
-	tick_length += tick_length_base - old_tick_length_base;
+	tick_length		+= tick_length_base - prev_base;
 }
 
 static void ntp_update_offset(long offset)
-- 
cgit v1.2.3


From bc26c31d446bc9c24cd6f7003777a05fe268ae48 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 12:17:36 +0100
Subject: time: ntp: refactor up ntp_update_frequency()

Impact: cleanup, no functionality changed

Change ntp_update_frequency() from a hard to follow code
flow that uses global variables as temporaries, to a clean
input+output flow.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 7d281d9fbe3..f1abad73857 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -83,10 +83,8 @@ static long			ntp_tick_adj;
  */
 static void ntp_update_frequency(void)
 {
-	u64 prev_base;
 	u64 second_length;
-
-	prev_base = tick_length_base;
+	u64 new_base;
 
 	second_length		 = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
 						<< NTP_SCALE_SHIFT;
@@ -94,16 +92,15 @@ static void ntp_update_frequency(void)
 	second_length		+= (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
 	second_length		+= time_freq;
 
-	tick_length_base	 = second_length;
-
 	tick_nsec		 = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
-	tick_length_base	 = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
+	new_base		 = div_u64(second_length, NTP_INTERVAL_FREQ);
 
 	/*
 	 * Don't wait for the next second_overflow, apply
-	 * the change to the tick length immediately
+	 * the change to the tick length immediately:
 	 */
-	tick_length		+= tick_length_base - prev_base;
+	tick_length		+= new_base - tick_length_base;
+	tick_length_base	 = new_base;
 }
 
 static void ntp_update_offset(long offset)
-- 
cgit v1.2.3


From f939890b6687e05c42361655fb6610fa08f5a601 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 12:57:49 +0100
Subject: time: ntp: refactor and clean up ntp_update_offset()

Impact: cleanup, no functionality changed

- introduce the ntp_update_offset_fll() helper
- clean up the flow and variable naming

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2504	    114	    136	   2754	    ac2	ntp.o.before
   2504	    114	    136	   2754	    ac2	ntp.o.after

md5:
   01f7b8e1a5472a3056f9e4ae84d46315  ntp.o.before.asm
   01f7b8e1a5472a3056f9e4ae84d46315  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 44 ++++++++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 14 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index f1abad73857..ee437e1445d 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -103,10 +103,27 @@ static void ntp_update_frequency(void)
 	tick_length_base	 = new_base;
 }
 
+static inline s64 ntp_update_offset_fll(s64 freq_adj, s64 offset64, long secs)
+{
+	time_status &= ~STA_MODE;
+
+	if (secs < MINSEC)
+		return freq_adj;
+
+	if (!(time_status & STA_FLL) && (secs <= MAXSEC))
+		return freq_adj;
+
+	freq_adj += div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
+	time_status |= STA_MODE;
+
+	return freq_adj;
+}
+
 static void ntp_update_offset(long offset)
 {
-	long mtemp;
 	s64 freq_adj;
+	s64 offset64;
+	long secs;
 
 	if (!(time_status & STA_PLL))
 		return;
@@ -127,22 +144,21 @@ static void ntp_update_offset(long offset)
 	 */
 	if (time_status & STA_FREQHOLD || time_reftime == 0)
 		time_reftime = xtime.tv_sec;
-	mtemp = xtime.tv_sec - time_reftime;
+
+	secs = xtime.tv_sec - time_reftime;
 	time_reftime = xtime.tv_sec;
 
-	freq_adj = (s64)offset * mtemp;
-	freq_adj <<= NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant);
-	time_status &= ~STA_MODE;
-	if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
-		freq_adj += div_s64((s64)offset << (NTP_SCALE_SHIFT - SHIFT_FLL),
-				    mtemp);
-		time_status |= STA_MODE;
-	}
-	freq_adj += time_freq;
-	freq_adj = min(freq_adj, MAXFREQ_SCALED);
-	time_freq = max(freq_adj, -MAXFREQ_SCALED);
+	offset64    = offset;
+	freq_adj    = (offset64 * secs) <<
+			(NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant));
+
+	freq_adj    = ntp_update_offset_fll(freq_adj, offset64, secs);
+
+	freq_adj    = min(freq_adj + time_freq, MAXFREQ_SCALED);
+
+	time_freq   = max(freq_adj, -MAXFREQ_SCALED);
 
-	time_offset = div_s64((s64)offset << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ);
+	time_offset = div_s64(offset64 << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ);
 }
 
 /**
-- 
cgit v1.2.3


From 478b7aab1682246a3d1e76e27a0aecb2f0013379 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 13:22:23 +0100
Subject: time: ntp: simplify ntp_update_offset_fll()

Impact: cleanup, no functionality changed

Change ntp_update_offset_fll() to delta logic instead of
absolute value logic. This eliminates 'freq_adj' from the
function.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index ee437e1445d..5202dde2f0a 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -103,20 +103,19 @@ static void ntp_update_frequency(void)
 	tick_length_base	 = new_base;
 }
 
-static inline s64 ntp_update_offset_fll(s64 freq_adj, s64 offset64, long secs)
+static inline s64 ntp_update_offset_fll(s64 offset64, long secs)
 {
 	time_status &= ~STA_MODE;
 
 	if (secs < MINSEC)
-		return freq_adj;
+		return 0;
 
 	if (!(time_status & STA_FLL) && (secs <= MAXSEC))
-		return freq_adj;
+		return 0;
 
-	freq_adj += div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
 	time_status |= STA_MODE;
 
-	return freq_adj;
+	return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
 }
 
 static void ntp_update_offset(long offset)
@@ -152,7 +151,7 @@ static void ntp_update_offset(long offset)
 	freq_adj    = (offset64 * secs) <<
 			(NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant));
 
-	freq_adj    = ntp_update_offset_fll(freq_adj, offset64, secs);
+	freq_adj    += ntp_update_offset_fll(offset64, secs);
 
 	freq_adj    = min(freq_adj + time_freq, MAXFREQ_SCALED);
 
-- 
cgit v1.2.3


From c7986acba211e8285e14c9603fb89e6f4ea0b9f8 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 13:29:09 +0100
Subject: time: ntp: micro-optimize ntp_update_offset()

Impact: cleanup, no functionality changed

The time_reftime update in ntp_update_offset() to xtime.tv_sec
is a convoluted way of saying that we want to freeze the frequency
and want the 'secs' delta to be 0. Also make this branch unlikely.

This shaves off 8 bytes from the code size:

   text	   data	    bss	    dec	    hex	filename
   2504	    114	    136	   2754	    ac2	ntp.o.before
   2496	    114	    136	   2746	    aba	ntp.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 5202dde2f0a..580a3502869 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -141,10 +141,10 @@ static void ntp_update_offset(long offset)
 	 * Select how the frequency is to be controlled
 	 * and in which mode (PLL or FLL).
 	 */
-	if (time_status & STA_FREQHOLD || time_reftime == 0)
-		time_reftime = xtime.tv_sec;
-
 	secs = xtime.tv_sec - time_reftime;
+	if (unlikely(time_status & STA_FREQHOLD || time_reftime == 0))
+		secs = 0;
+
 	time_reftime = xtime.tv_sec;
 
 	offset64    = offset;
-- 
cgit v1.2.3


From 10dd31a7a17254d6ba793305fc590455393e610e Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 13:38:40 +0100
Subject: time: ntp: fix bug in ntp_update_offset() & do_adjtimex()

Impact: change (fix) the way the NTP PLL seconds offset is initialized/tracked

Fix a bug and do a micro-optimization:

When PLL is enabled we do not reset time_reftime. If the PLL
was off for a long time (for example after bootup), this is
arguably the wrong thing to do.

We already had a hack for the common boot-time case in
ntp_update_offset(), in form of:

	if (unlikely(time_status & STA_FREQHOLD || time_reftime == 0))
 		secs = 0;

But the update delta should be reset later on too - not just when
the PLL is enabled for the first time after bootup.

So do it on !STA_PLL -> STA_PLL transitions.

This changes behavior, as previously if ntpd was disabled for
a long time and we restarted it, we'd run from that last update,
with a very large delta.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 580a3502869..fc08eb10ced 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -142,7 +142,7 @@ static void ntp_update_offset(long offset)
 	 * and in which mode (PLL or FLL).
 	 */
 	secs = xtime.tv_sec - time_reftime;
-	if (unlikely(time_status & STA_FREQHOLD || time_reftime == 0))
+	if (unlikely(time_status & STA_FREQHOLD))
 		secs = 0;
 
 	time_reftime = xtime.tv_sec;
@@ -394,6 +394,13 @@ int do_adjtimex(struct timex *txc)
 			}
 			/* only set allowed bits */
 			time_status &= STA_RONLY;
+			/*
+			 * If we turn on PLL adjustments then reset the
+			 * reference time to current time.
+			 */
+			if (!(time_status & STA_PLL) && (txc->status & STA_PLL))
+				time_reftime = xtime.tv_sec;
+
 			time_status |= txc->status & ~STA_RONLY;
 
 			switch (time_state) {
-- 
cgit v1.2.3


From 80f2257116474ceed5fccab510b4f7245c0f49d7 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 15:15:32 +0100
Subject: time: ntp: refactor do_adjtimex()

Impact: cleanup, no functionality changed

do_adjtimex() is currently a monster function with a maze of
branches. Refactor the txc->modes setting aspects of it into
two new helper functions:

	process_adj_status()
	process_adjtimex_modes()

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2512	    114	    136	   2762	    aca	ntp.o.before
   2512	    114	    136	   2762	    aca	ntp.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 182 +++++++++++++++++++++++++++++-------------------------
 1 file changed, 99 insertions(+), 83 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index fc08eb10ced..aded09be98c 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -332,6 +332,102 @@ static void notify_cmos_timer(void)
 static inline void notify_cmos_timer(void) { }
 #endif
 
+
+/*
+ * Propagate a new txc->status value into the NTP state:
+ */
+static inline void process_adj_status(struct timex *txc, struct timespec *ts)
+{
+	long now;
+
+	if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) {
+		time_state = TIME_OK;
+		time_status = STA_UNSYNC;
+	}
+	/* only set allowed bits */
+	time_status &= STA_RONLY;
+
+	/*
+	 * If we turn on PLL adjustments then reset the
+	 * reference time to current time.
+	 */
+	if (!(time_status & STA_PLL) && (txc->status & STA_PLL))
+		time_reftime = xtime.tv_sec;
+
+	time_status |= txc->status & ~STA_RONLY;
+
+	switch (time_state) {
+	case TIME_OK:
+	start_timer:
+		now = ts->tv_sec;
+		if (time_status & STA_INS) {
+			time_state = TIME_INS;
+			now += 86400 - now % 86400;
+			hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
+		} else if (time_status & STA_DEL) {
+			time_state = TIME_DEL;
+			now += 86400 - (now + 1) % 86400;
+			hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
+		}
+		break;
+	case TIME_INS:
+	case TIME_DEL:
+		time_state = TIME_OK;
+		goto start_timer;
+	case TIME_WAIT:
+		if (!(time_status & (STA_INS | STA_DEL)))
+			time_state = TIME_OK;
+		break;
+	case TIME_OOP:
+		hrtimer_restart(&leap_timer);
+		break;
+	}
+}
+/*
+ * Called with the xtime lock held, so we can access and modify
+ * all the global NTP state:
+ */
+static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts)
+{
+	if (txc->modes & ADJ_STATUS)
+		process_adj_status(txc, ts);
+
+	if (txc->modes & ADJ_NANO)
+		time_status |= STA_NANO;
+	if (txc->modes & ADJ_MICRO)
+		time_status &= ~STA_NANO;
+
+	if (txc->modes & ADJ_FREQUENCY) {
+		time_freq = (s64)txc->freq * PPM_SCALE;
+		time_freq = min(time_freq, MAXFREQ_SCALED);
+		time_freq = max(time_freq, -MAXFREQ_SCALED);
+	}
+
+	if (txc->modes & ADJ_MAXERROR)
+		time_maxerror = txc->maxerror;
+	if (txc->modes & ADJ_ESTERROR)
+		time_esterror = txc->esterror;
+
+	if (txc->modes & ADJ_TIMECONST) {
+		time_constant = txc->constant;
+		if (!(time_status & STA_NANO))
+			time_constant += 4;
+		time_constant = min(time_constant, (long)MAXTC);
+		time_constant = max(time_constant, 0l);
+	}
+
+	if (txc->modes & ADJ_TAI && txc->constant > 0)
+		time_tai = txc->constant;
+
+	if (txc->modes & ADJ_OFFSET)
+		ntp_update_offset(txc->offset);
+	if (txc->modes & ADJ_TICK)
+		tick_usec = txc->tick;
+
+	if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
+		ntp_update_frequency();
+}
+
 /*
  * adjtimex mainly allows reading (and writing, if superuser) of
  * kernel time-keeping variables. used by xntpd.
@@ -383,90 +479,10 @@ int do_adjtimex(struct timex *txc)
 		txc->offset = save_adjust;
 		goto adj_done;
 	}
-	if (txc->modes) {
-		long sec;
-
-		if (txc->modes & ADJ_STATUS) {
-			if ((time_status & STA_PLL) &&
-			    !(txc->status & STA_PLL)) {
-				time_state = TIME_OK;
-				time_status = STA_UNSYNC;
-			}
-			/* only set allowed bits */
-			time_status &= STA_RONLY;
-			/*
-			 * If we turn on PLL adjustments then reset the
-			 * reference time to current time.
-			 */
-			if (!(time_status & STA_PLL) && (txc->status & STA_PLL))
-				time_reftime = xtime.tv_sec;
-
-			time_status |= txc->status & ~STA_RONLY;
-
-			switch (time_state) {
-			case TIME_OK:
-			start_timer:
-				sec = ts.tv_sec;
-				if (time_status & STA_INS) {
-					time_state = TIME_INS;
-					sec += 86400 - sec % 86400;
-					hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
-				} else if (time_status & STA_DEL) {
-					time_state = TIME_DEL;
-					sec += 86400 - (sec + 1) % 86400;
-					hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
-				}
-				break;
-			case TIME_INS:
-			case TIME_DEL:
-				time_state = TIME_OK;
-				goto start_timer;
-				break;
-			case TIME_WAIT:
-				if (!(time_status & (STA_INS | STA_DEL)))
-					time_state = TIME_OK;
-				break;
-			case TIME_OOP:
-				hrtimer_restart(&leap_timer);
-				break;
-			}
-		}
-
-		if (txc->modes & ADJ_NANO)
-			time_status |= STA_NANO;
-		if (txc->modes & ADJ_MICRO)
-			time_status &= ~STA_NANO;
 
-		if (txc->modes & ADJ_FREQUENCY) {
-			time_freq = (s64)txc->freq * PPM_SCALE;
-			time_freq = min(time_freq, MAXFREQ_SCALED);
-			time_freq = max(time_freq, -MAXFREQ_SCALED);
-		}
-
-		if (txc->modes & ADJ_MAXERROR)
-			time_maxerror = txc->maxerror;
-		if (txc->modes & ADJ_ESTERROR)
-			time_esterror = txc->esterror;
-
-		if (txc->modes & ADJ_TIMECONST) {
-			time_constant = txc->constant;
-			if (!(time_status & STA_NANO))
-				time_constant += 4;
-			time_constant = min(time_constant, (long)MAXTC);
-			time_constant = max(time_constant, 0l);
-		}
-
-		if (txc->modes & ADJ_TAI && txc->constant > 0)
-			time_tai = txc->constant;
-
-		if (txc->modes & ADJ_OFFSET)
-			ntp_update_offset(txc->offset);
-		if (txc->modes & ADJ_TICK)
-			tick_usec = txc->tick;
-
-		if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
-			ntp_update_frequency();
-	}
+	/* If there are input parameters, then process them: */
+	if (txc->modes)
+		process_adjtimex_modes(txc, &ts);
 
 	txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ,
 				  NTP_SCALE_SHIFT);
-- 
cgit v1.2.3


From e96291653b2e4df02f160b574070f6e632868e5e Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 15:35:18 +0100
Subject: time: ntp: refactor do_adjtimex() some more

Impact: cleanup, no functionality changed

Further simplify do_adjtimex():

 - introduce the ntp_start_leap_timer() helper function
 - eliminate the goto adj_done complication

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 61 ++++++++++++++++++++++++++++++++-----------------------
 1 file changed, 36 insertions(+), 25 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index aded09be98c..4346ed6e623 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -332,14 +332,33 @@ static void notify_cmos_timer(void)
 static inline void notify_cmos_timer(void) { }
 #endif
 
+/*
+ * Start the leap seconds timer:
+ */
+static inline void ntp_start_leap_timer(struct timespec *ts)
+{
+	long now = ts->tv_sec;
+
+	if (time_status & STA_INS) {
+		time_state = TIME_INS;
+		now += 86400 - now % 86400;
+		hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
+
+		return;
+	}
+
+	if (time_status & STA_DEL) {
+		time_state = TIME_DEL;
+		now += 86400 - (now + 1) % 86400;
+		hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
+	}
+}
 
 /*
  * Propagate a new txc->status value into the NTP state:
  */
 static inline void process_adj_status(struct timex *txc, struct timespec *ts)
 {
-	long now;
-
 	if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) {
 		time_state = TIME_OK;
 		time_status = STA_UNSYNC;
@@ -358,22 +377,12 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
 
 	switch (time_state) {
 	case TIME_OK:
-	start_timer:
-		now = ts->tv_sec;
-		if (time_status & STA_INS) {
-			time_state = TIME_INS;
-			now += 86400 - now % 86400;
-			hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-		} else if (time_status & STA_DEL) {
-			time_state = TIME_DEL;
-			now += 86400 - (now + 1) % 86400;
-			hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-		}
+		ntp_start_leap_timer(ts);
 		break;
 	case TIME_INS:
 	case TIME_DEL:
 		time_state = TIME_OK;
-		goto start_timer;
+		ntp_start_leap_timer(ts);
 	case TIME_WAIT:
 		if (!(time_status & (STA_INS | STA_DEL)))
 			time_state = TIME_OK;
@@ -394,6 +403,7 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts
 
 	if (txc->modes & ADJ_NANO)
 		time_status |= STA_NANO;
+
 	if (txc->modes & ADJ_MICRO)
 		time_status &= ~STA_NANO;
 
@@ -405,6 +415,7 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts
 
 	if (txc->modes & ADJ_MAXERROR)
 		time_maxerror = txc->maxerror;
+
 	if (txc->modes & ADJ_ESTERROR)
 		time_esterror = txc->esterror;
 
@@ -421,6 +432,7 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts
 
 	if (txc->modes & ADJ_OFFSET)
 		ntp_update_offset(txc->offset);
+
 	if (txc->modes & ADJ_TICK)
 		tick_usec = txc->tick;
 
@@ -457,7 +469,7 @@ int do_adjtimex(struct timex *txc)
 		if (txc->modes & ADJ_TICK &&
 		    (txc->tick <  900000/USER_HZ ||
 		     txc->tick > 1100000/USER_HZ))
-				return -EINVAL;
+			return -EINVAL;
 
 		if (txc->modes & ADJ_STATUS && time_state != TIME_OK)
 			hrtimer_cancel(&leap_timer);
@@ -467,7 +479,6 @@ int do_adjtimex(struct timex *txc)
 
 	write_seqlock_irq(&xtime_lock);
 
-	/* If there are input parameters, then process them */
 	if (txc->modes & ADJ_ADJTIME) {
 		long save_adjust = time_adjust;
 
@@ -477,19 +488,18 @@ int do_adjtimex(struct timex *txc)
 			ntp_update_frequency();
 		}
 		txc->offset = save_adjust;
-		goto adj_done;
-	}
+	} else {
 
-	/* If there are input parameters, then process them: */
-	if (txc->modes)
-		process_adjtimex_modes(txc, &ts);
+		/* If there are input parameters, then process them: */
+		if (txc->modes)
+			process_adjtimex_modes(txc, &ts);
 
-	txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ,
+		txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ,
 				  NTP_SCALE_SHIFT);
-	if (!(time_status & STA_NANO))
-		txc->offset /= NSEC_PER_USEC;
+		if (!(time_status & STA_NANO))
+			txc->offset /= NSEC_PER_USEC;
+	}
 
-adj_done:
 	result = time_state;	/* mostly `TIME_OK' */
 	if (time_status & (STA_UNSYNC|STA_CLOCKERR))
 		result = TIME_ERROR;
@@ -514,6 +524,7 @@ adj_done:
 	txc->calcnt	   = 0;
 	txc->errcnt	   = 0;
 	txc->stbcnt	   = 0;
+
 	write_sequnlock_irq(&xtime_lock);
 
 	txc->time.tv_sec = ts.tv_sec;
-- 
cgit v1.2.3


From 2b9d1496e7835a603c340e8f0dd81f4b74d5f248 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 15:48:43 +0100
Subject: time: ntp: make 64-bit constants more robust

Impact: cleanup, no functionality changed

 - make PPM_SCALE an explicit s64 constant, to
   remove (s64) casts from usage sites.

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2536	    114	    136	   2786	    ae2	ntp.o.before
   2536	    114	    136	   2786	    ae2	ntp.o.after

md5:
   40a7728d1188aa18e83e21a81fa7b150  ntp.o.before.asm
   40a7728d1188aa18e83e21a81fa7b150  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 4346ed6e623..7447d57e021 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -408,7 +408,7 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts
 		time_status &= ~STA_NANO;
 
 	if (txc->modes & ADJ_FREQUENCY) {
-		time_freq = (s64)txc->freq * PPM_SCALE;
+		time_freq = txc->freq * PPM_SCALE;
 		time_freq = min(time_freq, MAXFREQ_SCALED);
 		time_freq = max(time_freq, -MAXFREQ_SCALED);
 	}
@@ -505,7 +505,7 @@ int do_adjtimex(struct timex *txc)
 		result = TIME_ERROR;
 
 	txc->freq	   = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) *
-					 (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT);
+					 PPM_SCALE_INV, NTP_SCALE_SHIFT);
 	txc->maxerror	   = time_maxerror;
 	txc->esterror	   = time_esterror;
 	txc->status	   = time_status;
-- 
cgit v1.2.3


From 069569e025706f27f939785f86a94d5d8ce55dce Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 16:03:37 +0100
Subject: time: ntp: simplify ntp_tick_adj calculations

Impact: micro-optimization

Convert the (internal) ntp_tick_adj value we store from unscaled
units to scaled units. This is a constant that we never modify,
so scaling it up once during bootup is enough - we dont have to
do it for every adjustment step.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 7447d57e021..a3fe7ef2d83 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -71,7 +71,8 @@ static long			time_reftime;
 
 long				time_adjust;
 
-static long			ntp_tick_adj;
+/* constant (boot-param configurable) NTP tick adjustment (upscaled)	*/
+static s64			ntp_tick_adj;
 
 /*
  * NTP methods:
@@ -89,7 +90,7 @@ static void ntp_update_frequency(void)
 	second_length		 = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
 						<< NTP_SCALE_SHIFT;
 
-	second_length		+= (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
+	second_length		+= ntp_tick_adj;
 	second_length		+= time_freq;
 
 	tick_nsec		 = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
@@ -540,6 +541,8 @@ int do_adjtimex(struct timex *txc)
 static int __init ntp_tick_adj_setup(char *str)
 {
 	ntp_tick_adj = simple_strtol(str, NULL, 0);
+	ntp_tick_adj <<= NTP_SCALE_SHIFT;
+
 	return 1;
 }
 
-- 
cgit v1.2.3


From 39854fe8c165872d743f6a0c4860ca2de8e45ac9 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Sun, 22 Feb 2009 16:06:58 +0100
Subject: time: ntp: clean up second_overflow()

Impact: cleanup, no functionality changed

The 'time_adj' local variable is named in a very confusing
way because it almost shadows the 'time_adjust' global
variable - which is used in this same function.

Rename it to 'delta' - to make them stand apart more clearly.

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2545	    114	    144	   2803	    af3	ntp.o.before
   2545	    114	    144	   2803	    af3	ntp.o.after

md5:
   1bf0b3be564512279ba7cee299d1d2be  ntp.o.before.asm
   1bf0b3be564512279ba7cee299d1d2be  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index a3fe7ef2d83..c74eb7d9d85 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -236,7 +236,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
  */
 void second_overflow(void)
 {
-	s64 time_adj;
+	s64 delta;
 
 	/* Bump the maxerror field */
 	time_maxerror += MAXFREQ / NSEC_PER_USEC;
@@ -249,10 +249,11 @@ void second_overflow(void)
 	 * Compute the phase adjustment for the next second. The offset is
 	 * reduced by a fixed factor times the time constant.
 	 */
-	tick_length	= tick_length_base;
-	time_adj	= shift_right(time_offset, SHIFT_PLL + time_constant);
-	time_offset	-= time_adj;
-	tick_length	+= time_adj;
+	tick_length	 = tick_length_base;
+
+	delta		 = shift_right(time_offset, SHIFT_PLL + time_constant);
+	time_offset	-= delta;
+	tick_length	+= delta;
 
 	if (!time_adjust)
 		return;
-- 
cgit v1.2.3


From a2a5ac8650b570bea3cb3614f77739dcd07d6632 Mon Sep 17 00:00:00 2001
From: John Stultz <johnstul@us.ibm.com>
Date: Thu, 26 Feb 2009 09:46:14 -0800
Subject: time: ntp: fix bug in ntp_update_offset() & do_adjtimex(), fix

The time_status conditional was accidentally placed right after we clear
the checked time_status bits, which causes us to take the conditional
every time through. This fixes it by moving the conditional to before we
clear the time_status bits.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Clark Williams <williams@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/time/ntp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'kernel/time')

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index c74eb7d9d85..7fc64375ff4 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -365,8 +365,6 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
 		time_state = TIME_OK;
 		time_status = STA_UNSYNC;
 	}
-	/* only set allowed bits */
-	time_status &= STA_RONLY;
 
 	/*
 	 * If we turn on PLL adjustments then reset the
@@ -375,6 +373,8 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
 	if (!(time_status & STA_PLL) && (txc->status & STA_PLL))
 		time_reftime = xtime.tv_sec;
 
+	/* only set allowed bits */
+	time_status &= STA_RONLY;
 	time_status |= txc->status & ~STA_RONLY;
 
 	switch (time_state) {
-- 
cgit v1.2.3