Commit 53bbfa9e authored by Ingo Molnar's avatar Ingo Molnar
Browse files

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: default avatarIngo Molnar <mingo@elte.hu>
parent fdcedf7b

kernel/time/ntp.c

+81 −48
Original line number Diff line number Diff line 
/*

 * 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) */



/* USER_HZ period (usecs): */

unsigned long			tick_usec = TICK_USEC;



/* ACTHZ period (nsecs): */

unsigned long			tick_nsec;



u64				tick_length;

static u64			tick_length_base;



static struct hrtimer		leap_timer;



#define MAX_TICKADJ		500		/* microsecs */

#define MAX_TICKADJ_SCALED	(((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \

				  NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)

#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)	*/



/*

 * 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)

{

	u64 old_tick_length_base = tick_length_base;
@@ -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++;
@@ -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))

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