Commit 7ec88e4b authored by Arnd Bergmann's avatar Arnd Bergmann Committed by John Stultz
Browse files

ntp/pps: use timespec64 for hardpps() 



There is only one user of the hardpps function in the kernel, so
it makes sense to atomically change it over to using 64-bit
timestamps for y2038 safety. In the hardpps implementation,
we also need to change the pps_normtime structure, which is
similar to struct timespec and also requires a 64-bit
seconds portion.

This introduces two temporary variables in pps_kc_event() to
do the conversion, they will be removed again in the next step,
which seemed preferable to having a larger patch changing it
all at the same time.

Acked-by: default avatarRichard Cochran <richardcochran@gmail.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
parent 9ffecb10

drivers/pps/kc.c

+3 −1
Original line number Diff line number Diff line
@@ -113,10 +113,12 @@ void pps_kc_event(struct pps_device *pps, struct pps_event_time *ts, 
		int event)

{

	unsigned long flags;

	struct timespec64 real = timespec_to_timespec64(ts->ts_real);

	struct timespec64 raw = timespec_to_timespec64(ts->ts_raw);



	/* Pass some events to kernel consumer if activated */

	spin_lock_irqsave(&pps_kc_hardpps_lock, flags);

	if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode)

		hardpps(&ts->ts_real, &ts->ts_raw);

		hardpps(&real, &raw);

	spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags);

}

include/linux/timex.h

+1 −1
Original line number Diff line number Diff line
@@ -152,7 +152,7 @@ extern unsigned long tick_nsec; /* SHIFTED_HZ period (nsec) */ 
#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)



extern int do_adjtimex(struct timex *);

extern void hardpps(const struct timespec *, const struct timespec *);

extern void hardpps(const struct timespec64 *, const struct timespec64 *);



int read_current_timer(unsigned long *timer_val);

void ntp_notify_cmos_timer(void);

kernel/time/ntp.c

+6 −6
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ static time64_t ntp_next_leap_sec = TIME64_MAX; 
static int pps_valid;		/* signal watchdog counter */

static long pps_tf[3];		/* phase median filter */

static long pps_jitter;		/* current jitter (ns) */

static struct timespec pps_fbase; /* beginning of the last freq interval */

static struct timespec64 pps_fbase; /* beginning of the last freq interval */

static int pps_shift;		/* current interval duration (s) (shift) */

static int pps_intcnt;		/* interval counter */

static s64 pps_freq;		/* frequency offset (scaled ns/s) */
@@ -773,13 +773,13 @@ int __do_adjtimex(struct timex *txc, struct timespec64 *ts, s32 *time_tai) 
 * pps_normtime.nsec has a range of ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ]

 * while timespec.tv_nsec has a range of [0, NSEC_PER_SEC) */

struct pps_normtime {

	__kernel_time_t	sec;	/* seconds */

	s64		sec;	/* seconds */

	long		nsec;	/* nanoseconds */

};



/* normalize the timestamp so that nsec is in the

   ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] interval */

static inline struct pps_normtime pps_normalize_ts(struct timespec ts)

static inline struct pps_normtime pps_normalize_ts(struct timespec64 ts)

{

	struct pps_normtime norm = {

		.sec = ts.tv_sec,
@@ -861,7 +861,7 @@ static long hardpps_update_freq(struct pps_normtime freq_norm) 
		pps_errcnt++;

		pps_dec_freq_interval();

		printk_deferred(KERN_ERR

			"hardpps: PPSERROR: interval too long - %ld s\n",

			"hardpps: PPSERROR: interval too long - %lld s\n",

			freq_norm.sec);

		return 0;

	}
@@ -948,7 +948,7 @@ static void hardpps_update_phase(long error) 
 * This code is based on David Mills's reference nanokernel

 * implementation. It was mostly rewritten but keeps the same idea.

 */

void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)

void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)

{

	struct pps_normtime pts_norm, freq_norm;
@@ -969,7 +969,7 @@ void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) 
	}



	/* ok, now we have a base for frequency calculation */

	freq_norm = pps_normalize_ts(timespec_sub(*raw_ts, pps_fbase));

	freq_norm = pps_normalize_ts(timespec64_sub(*raw_ts, pps_fbase));



	/* check that the signal is in the range

	 * [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */

kernel/time/ntp_internal.h

+1 −1
Original line number Diff line number Diff line
@@ -9,5 +9,5 @@ extern ktime_t ntp_get_next_leap(void); 
extern int second_overflow(unsigned long secs);

extern int ntp_validate_timex(struct timex *);

extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);

extern void __hardpps(const struct timespec *, const struct timespec *);

extern void __hardpps(const struct timespec64 *, const struct timespec64 *);

#endif /* _LINUX_NTP_INTERNAL_H */

kernel/time/timekeeping.c

+1 −1
Original line number Diff line number Diff line
@@ -2025,7 +2025,7 @@ int do_adjtimex(struct timex *txc) 
/**

 * hardpps() - Accessor function to NTP __hardpps function

 */

void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)

void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)

{

	unsigned long flags;

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