Commit 64764cf6 authored by Sven Schnelle's avatar Sven Schnelle Committed by Alexander Gordeev
Browse files

s390/stp: Remove leap second support 



With moving time steering to userspace, there's no need
to handle leap seconds inside the kernel. Remove it.

Signed-off-by: default avatarSven Schnelle <svens@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent 94ecbf1e

arch/s390/kernel/time.c

+0 −77
Original line number Diff line number Diff line
@@ -558,81 +558,6 @@ static int stp_sync_clock(void *data) 
	return 0;

}



static int stp_clear_leap(void)

{

	struct __kernel_timex txc;

	int ret;



	memset(&txc, 0, sizeof(txc));



	ret = do_adjtimex(&txc);

	if (ret < 0)

		return ret;



	txc.modes = ADJ_STATUS;

	txc.status &= ~(STA_INS|STA_DEL);

	return do_adjtimex(&txc);

}



static void stp_check_leap(void)

{

	struct stp_stzi stzi;

	struct stp_lsoib *lsoib = &stzi.lsoib;

	struct __kernel_timex txc;

	int64_t timediff;

	int leapdiff, ret;



	if (!stp_info.lu || !check_sync_clock()) {

		/*

		 * Either a scheduled leap second was removed by the operator,

		 * or STP is out of sync. In both cases, clear the leap second

		 * kernel flags.

		 */

		if (stp_clear_leap() < 0)

			pr_err("failed to clear leap second flags\n");

		return;

	}



	if (chsc_stzi(stp_page, &stzi, sizeof(stzi))) {

		pr_err("stzi failed\n");

		return;

	}



	timediff = tod_to_ns(lsoib->nlsout - get_tod_clock()) / NSEC_PER_SEC;

	leapdiff = lsoib->nlso - lsoib->also;



	if (leapdiff != 1 && leapdiff != -1) {

		pr_err("Cannot schedule %d leap seconds\n", leapdiff);

		return;

	}



	if (timediff < 0) {

		if (stp_clear_leap() < 0)

			pr_err("failed to clear leap second flags\n");

	} else if (timediff < 7200) {

		memset(&txc, 0, sizeof(txc));

		ret = do_adjtimex(&txc);

		if (ret < 0)

			return;



		txc.modes = ADJ_STATUS;

		if (leapdiff > 0)

			txc.status |= STA_INS;

		else

			txc.status |= STA_DEL;

		ret = do_adjtimex(&txc);

		if (ret < 0)

			pr_err("failed to set leap second flags\n");

		/* arm Timer to clear leap second flags */

		mod_timer(&stp_timer, jiffies + secs_to_jiffies(14400));

	} else {

		/* The day the leap second is scheduled for hasn't been reached. Retry

		 * in one hour.

		 */

		mod_timer(&stp_timer, jiffies + secs_to_jiffies(3600));

	}

}



/*

 * STP work. Check for the STP state and take over the clock

 * synchronization if the STP clock source is usable.
@@ -674,8 +599,6 @@ static void stp_work_fn(struct work_struct *work) 
		 * Retry after a second.

		 */

		mod_timer(&stp_timer, jiffies + msecs_to_jiffies(MSEC_PER_SEC));

	else if (stp_info.lu)

		stp_check_leap();



out_unlock:

	mutex_unlock(&stp_mutex);