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commit c0e49c708814ec783726fe92202371847703c5ed
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Author: Miroslav Lichvar <mlichvar@redhat.com>
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Date:   Mon Nov 12 17:27:58 2018 +0100
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    sysoff: Initialize data for ioctl(PTP_SYS_OFFSET).
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    This fixes valgrind errors.
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    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
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diff --git a/sysoff.c b/sysoff.c
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index f7b6240..407a01c 100644
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--- a/sysoff.c
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+++ b/sysoff.c
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@@ -18,6 +18,7 @@
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  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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  */
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 #include <stdio.h>
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+#include <string.h>
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 #include <sys/ioctl.h>
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 #include <linux/ptp_clock.h>
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@@ -76,6 +77,7 @@ int sysoff_measure(int fd, int n_samples,
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 		   int64_t *result, uint64_t *ts, int64_t *delay)
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 {
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 	struct ptp_sys_offset pso;
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+	memset(&pso, 0, sizeof(pso));
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 	pso.n_samples = n_samples;
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 	if (ioctl(fd, PTP_SYS_OFFSET, &pso)) {
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 		perror("ioctl PTP_SYS_OFFSET");
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commit 93baf34adb81046a5e1c3b9a3e685029f2046993
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Author: Miroslav Lichvar <mlichvar@redhat.com>
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Date:   Mon Nov 12 17:27:59 2018 +0100
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    sysoff: Extend API for different sysoff methods.
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    The kernel supports different PTP_SYS_OFFSET* ioctls. Use the sysoff
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    enum to allow selecting between them in sysoff_measure().
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    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
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diff --git a/phc2sys.c b/phc2sys.c
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index 15f8d75..2cd477a 100644
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--- a/phc2sys.c
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+++ b/phc2sys.c
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@@ -74,7 +74,7 @@ struct clock {
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 	LIST_ENTRY(clock) dst_list;
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 	clockid_t clkid;
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 	int phc_index;
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-	int sysoff_supported;
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+	int sysoff_method;
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 	int is_utc;
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 	int dest_only;
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 	int state;
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@@ -255,9 +255,8 @@ static struct clock *clock_add(struct node *node, char *device)
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 		c->servo = servo_add(node, c);
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 	if (clkid != CLOCK_INVALID && clkid != CLOCK_REALTIME)
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-		c->sysoff_supported = (SYSOFF_SUPPORTED ==
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-				       sysoff_probe(CLOCKID_TO_FD(clkid),
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-						    node->phc_readings));
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+		c->sysoff_method = sysoff_probe(CLOCKID_TO_FD(clkid),
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+						node->phc_readings);
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 	LIST_INSERT_HEAD(&node->clocks, c, list);
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 	return c;
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@@ -784,11 +783,12 @@ static int do_loop(struct node *node, int subscriptions)
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 				continue;
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 			if (clock->clkid == CLOCK_REALTIME &&
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-			    node->master->sysoff_supported) {
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+			    node->master->sysoff_method >= 0) {
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 				/* use sysoff */
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 				if (sysoff_measure(CLOCKID_TO_FD(node->master->clkid),
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+						   node->master->sysoff_method,
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 						   node->phc_readings,
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-						   &offset, &ts, &delay))
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+						   &offset, &ts, &delay) < 0)
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 					return -1;
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 			} else {
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 				/* use phc */
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diff --git a/phc_ctl.c b/phc_ctl.c
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index 4a78a19..b9a9cf4 100644
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--- a/phc_ctl.c
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+++ b/phc_ctl.c
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@@ -367,10 +367,12 @@ static int do_cmp(clockid_t clkid, int cmdc, char *cmdv[])
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 	struct timespec ts, rta, rtb;
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 	int64_t sys_offset, delay = 0, offset;
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 	uint64_t sys_ts;
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+	int method;
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-	if (SYSOFF_SUPPORTED ==
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-	    sysoff_measure(CLOCKID_TO_FD(clkid),
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-			   9, &sys_offset, &sys_ts, &delay)) {
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+	method = sysoff_probe(CLOCKID_TO_FD(clkid), 9);
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+
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+	if (method >= 0 && sysoff_measure(CLOCKID_TO_FD(clkid), method, 9,
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+					  &sys_offset, &sys_ts, &delay) >= 0) {
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 		pr_notice( "offset from CLOCK_REALTIME is %"PRId64"ns\n",
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 			sys_offset);
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 		return 0;
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diff --git a/sysoff.c b/sysoff.c
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index 407a01c..f709a9b 100644
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--- a/sysoff.c
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+++ b/sysoff.c
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@@ -73,8 +73,8 @@ static int64_t sysoff_estimate(struct ptp_clock_time *pct, int n_samples,
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 	return samples[0].offset;
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 }
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-int sysoff_measure(int fd, int n_samples,
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-		   int64_t *result, uint64_t *ts, int64_t *delay)
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+static int sysoff_basic(int fd, int n_samples,
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+			int64_t *result, uint64_t *ts, int64_t *delay)
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 {
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 	struct ptp_sys_offset pso;
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 	memset(&pso, 0, sizeof(pso));
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@@ -84,13 +84,24 @@ int sysoff_measure(int fd, int n_samples,
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 		return SYSOFF_RUN_TIME_MISSING;
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 	}
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 	*result = sysoff_estimate(pso.ts, n_samples, ts, delay);
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-	return SYSOFF_SUPPORTED;
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+	return SYSOFF_BASIC;
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+}
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+
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+int sysoff_measure(int fd, int method, int n_samples,
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+		   int64_t *result, uint64_t *ts, int64_t *delay)
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+{
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+	switch (method) {
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+	case SYSOFF_BASIC:
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+		return sysoff_basic(fd, n_samples, result, ts, delay);
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+	}
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+	return SYSOFF_COMPILE_TIME_MISSING;
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 }
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 int sysoff_probe(int fd, int n_samples)
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 {
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 	int64_t junk, delay;
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 	uint64_t ts;
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+	int i;
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 	if (n_samples > PTP_MAX_SAMPLES) {
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 		fprintf(stderr, "warning: %d exceeds kernel max readings %d\n",
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@@ -99,7 +110,13 @@ int sysoff_probe(int fd, int n_samples)
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 		return SYSOFF_RUN_TIME_MISSING;
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 	}
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-	return sysoff_measure(fd, n_samples, &junk, &ts, &delay);
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+	for (i = 0; i < SYSOFF_LAST; i++) {
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+		if (sysoff_measure(fd, i, n_samples, &junk, &ts, &delay) < 0)
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+			continue;
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+		return i;
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+	}
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+
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+	return SYSOFF_RUN_TIME_MISSING;
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 }
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 #else /* !PTP_SYS_OFFSET */
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diff --git a/sysoff.h b/sysoff.h
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index cb70265..02ecdfa 100644
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--- a/sysoff.h
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+++ b/sysoff.h
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@@ -21,13 +21,14 @@
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 #include <stdint.h>
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 enum {
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-	SYSOFF_SUPPORTED,
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-	SYSOFF_COMPILE_TIME_MISSING,
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-	SYSOFF_RUN_TIME_MISSING,
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+	SYSOFF_COMPILE_TIME_MISSING = -2,
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+	SYSOFF_RUN_TIME_MISSING = -1,
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+	SYSOFF_BASIC,
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+	SYSOFF_LAST,
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 };
63054e
 
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 /**
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- * Check to see if the PTP_SYS_OFFSET ioctl is supported.
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+ * Check to see if a PTP_SYS_OFFSET ioctl is supported.
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  * @param fd  An open file descriptor to a PHC device.
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  * @return  One of the SYSOFF_ enumeration values.
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  */
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@@ -36,11 +37,12 @@ int sysoff_probe(int fd, int n_samples);
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 /**
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  * Measure the offset between a PHC and the system time.
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  * @param fd         An open file descriptor to a PHC device.
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+ * @param method     A non-negative SYSOFF_ value returned by sysoff_probe().
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  * @param n_samples  The number of consecutive readings to make.
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  * @param result     The estimated offset in nanoseconds.
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  * @param ts         The system time corresponding to the 'result'.
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  * @param delay      The delay in reading of the clock in nanoseconds.
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  * @return  One of the SYSOFF_ enumeration values.
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  */
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-int sysoff_measure(int fd, int n_samples,
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+int sysoff_measure(int fd, int method, int n_samples,
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 		   int64_t *result, uint64_t *ts, int64_t *delay);
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63054e
commit 192b8e315c4585489d7aa7f59683035998805e40
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Author: Miroslav Lichvar <mlichvar@redhat.com>
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Date:   Mon Nov 12 17:28:00 2018 +0100
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    sysoff: Add support for PTP_SYS_OFFSET_PRECISE ioctl.
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    This ioctl uses cross timestamping for a more accurate measurement of
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    the offset. It is supported on some onboard Intel NICs using the e1000e
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    driver and a virtual PHC with the ptp_kvm driver.
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    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
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diff --git a/sysoff.c b/sysoff.c
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index f709a9b..9f65d95 100644
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--- a/sysoff.c
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+++ b/sysoff.c
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@@ -22,6 +22,7 @@
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 #include <sys/ioctl.h>
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 #include <linux/ptp_clock.h>
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+#include "print.h"
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 #include "sysoff.h"
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 #define NS_PER_SEC 1000000000LL
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@@ -39,6 +40,23 @@ static struct {
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 	uint64_t timestamp;
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 } samples[PTP_MAX_SAMPLES];
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+static int sysoff_precise(int fd, int64_t *result, uint64_t *ts)
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+{
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+#ifdef PTP_SYS_OFFSET_PRECISE
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+	struct ptp_sys_offset_precise pso;
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+	memset(&pso, 0, sizeof(pso));
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+	if (ioctl(fd, PTP_SYS_OFFSET_PRECISE, &pso)) {
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+		pr_debug("ioctl PTP_SYS_OFFSET_PRECISE: %m");
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+		return SYSOFF_RUN_TIME_MISSING;
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+	}
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+	*result = pctns(&pso.sys_realtime) - pctns(&pso.device);
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+	*ts = pctns(&pso.sys_realtime);
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+	return SYSOFF_PRECISE;
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+#else
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+	return SYSOFF_COMPILE_TIME_MISSING;
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+#endif
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+}
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+
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 static void insertion_sort(int length, int64_t interval, int64_t offset, uint64_t ts)
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 {
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 	int i = length - 1;
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@@ -91,6 +109,9 @@ int sysoff_measure(int fd, int method, int n_samples,
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 		   int64_t *result, uint64_t *ts, int64_t *delay)
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 {
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 	switch (method) {
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+	case SYSOFF_PRECISE:
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+		*delay = 0;
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+		return sysoff_precise(fd, result, ts);
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 	case SYSOFF_BASIC:
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 		return sysoff_basic(fd, n_samples, result, ts, delay);
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 	}
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diff --git a/sysoff.h b/sysoff.h
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index 02ecdfa..37f7353 100644
63054e
--- a/sysoff.h
63054e
+++ b/sysoff.h
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@@ -23,6 +23,7 @@
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 enum {
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 	SYSOFF_COMPILE_TIME_MISSING = -2,
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 	SYSOFF_RUN_TIME_MISSING = -1,
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+	SYSOFF_PRECISE,
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 	SYSOFF_BASIC,
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 	SYSOFF_LAST,
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 };
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63054e
commit 68a9011c9d7d859920da339ba59c14dc1d617a45
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Author: Miroslav Lichvar <mlichvar@redhat.com>
63054e
Date:   Mon Nov 12 17:28:01 2018 +0100
63054e
63054e
    sysoff: Add support for PTP_SYS_OFFSET_EXTENDED ioctl.
63054e
    
63054e
    This is a more accurate variant of the the PTP_SYS_OFFSET ioctl, which
63054e
    will probably be supported in future kernel versions.
63054e
    
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    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
63054e
63054e
diff --git a/sysoff.c b/sysoff.c
63054e
index 9f65d95..b993ee9 100644
63054e
--- a/sysoff.c
63054e
+++ b/sysoff.c
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@@ -71,17 +71,23 @@ static void insertion_sort(int length, int64_t interval, int64_t offset, uint64_
63054e
 	samples[i+1].timestamp = ts;
63054e
 }
63054e
 
63054e
-static int64_t sysoff_estimate(struct ptp_clock_time *pct, int n_samples,
63054e
-			       uint64_t *ts, int64_t *delay)
63054e
+static int64_t sysoff_estimate(struct ptp_clock_time *pct, int extended,
63054e
+			       int n_samples, uint64_t *ts, int64_t *delay)
63054e
 {
63054e
 	int64_t t1, t2, tp;
63054e
 	int64_t interval, offset;
63054e
 	int i;
63054e
 
63054e
 	for (i = 0; i < n_samples; i++) {
63054e
-		t1 = pctns(&pct[2*i]);
63054e
-		tp = pctns(&pct[2*i+1]);
63054e
-		t2 = pctns(&pct[2*i+2]);
63054e
+		if (extended) {
63054e
+			t1 = pctns(&pct[3*i]);
63054e
+			tp = pctns(&pct[3*i+1]);
63054e
+			t2 = pctns(&pct[3*i+2]);
63054e
+		} else {
63054e
+			t1 = pctns(&pct[2*i]);
63054e
+			tp = pctns(&pct[2*i+1]);
63054e
+			t2 = pctns(&pct[2*i+2]);
63054e
+		}
63054e
 		interval = t2 - t1;
63054e
 		offset = (t2 + t1) / 2 - tp;
63054e
 		insertion_sort(i, interval, offset, (t2 + t1) / 2);
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@@ -91,6 +97,24 @@ static int64_t sysoff_estimate(struct ptp_clock_time *pct, int n_samples,
63054e
 	return samples[0].offset;
63054e
 }
63054e
 
63054e
+static int sysoff_extended(int fd, int n_samples,
63054e
+			   int64_t *result, uint64_t *ts, int64_t *delay)
63054e
+{
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+#ifdef PTP_SYS_OFFSET_EXTENDED
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+	struct ptp_sys_offset_extended pso;
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+	memset(&pso, 0, sizeof(pso));
63054e
+	pso.n_samples = n_samples;
63054e
+	if (ioctl(fd, PTP_SYS_OFFSET_EXTENDED, &pso)) {
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+		pr_debug("ioctl PTP_SYS_OFFSET_EXTENDED: %m");
63054e
+		return SYSOFF_RUN_TIME_MISSING;
63054e
+	}
63054e
+	*result = sysoff_estimate(&pso.ts[0][0], 1, n_samples, ts, delay);
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+	return SYSOFF_EXTENDED;
63054e
+#else
63054e
+	return SYSOFF_COMPILE_TIME_MISSING;
63054e
+#endif
63054e
+}
63054e
+
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 static int sysoff_basic(int fd, int n_samples,
63054e
 			int64_t *result, uint64_t *ts, int64_t *delay)
63054e
 {
63054e
@@ -101,7 +125,7 @@ static int sysoff_basic(int fd, int n_samples,
63054e
 		perror("ioctl PTP_SYS_OFFSET");
63054e
 		return SYSOFF_RUN_TIME_MISSING;
63054e
 	}
63054e
-	*result = sysoff_estimate(pso.ts, n_samples, ts, delay);
63054e
+	*result = sysoff_estimate(pso.ts, 0, n_samples, ts, delay);
63054e
 	return SYSOFF_BASIC;
63054e
 }
63054e
 
63054e
@@ -112,6 +136,8 @@ int sysoff_measure(int fd, int method, int n_samples,
63054e
 	case SYSOFF_PRECISE:
63054e
 		*delay = 0;
63054e
 		return sysoff_precise(fd, result, ts);
63054e
+	case SYSOFF_EXTENDED:
63054e
+		return sysoff_extended(fd, n_samples, result, ts, delay);
63054e
 	case SYSOFF_BASIC:
63054e
 		return sysoff_basic(fd, n_samples, result, ts, delay);
63054e
 	}
63054e
diff --git a/sysoff.h b/sysoff.h
63054e
index 37f7353..79d2290 100644
63054e
--- a/sysoff.h
63054e
+++ b/sysoff.h
63054e
@@ -24,6 +24,7 @@ enum {
63054e
 	SYSOFF_COMPILE_TIME_MISSING = -2,
63054e
 	SYSOFF_RUN_TIME_MISSING = -1,
63054e
 	SYSOFF_PRECISE,
63054e
+	SYSOFF_EXTENDED,
63054e
 	SYSOFF_BASIC,
63054e
 	SYSOFF_LAST,
63054e
 };
63054e
63054e
commit 8142da41b61fb5b9ee4ad8f5ab56adb0447cd37b
63054e
Author: Miroslav Lichvar <mlichvar@redhat.com>
63054e
Date:   Mon Nov 12 17:28:02 2018 +0100
63054e
63054e
    phc2sys: Use reversed sysoff when synchronizing to system clock.
63054e
    
63054e
    If synchronizing a PHC to the system clock, use one of the
63054e
    PTP_SYS_OFFSET ioctls (if supported) to measure the offset between the
63054e
    two clocks. Negate the offset and switch the timestamp before passing
63054e
    them to the servo.
63054e
    
63054e
    This makes the synchronization between PHC and system clock symmetric.
63054e
    
63054e
    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
63054e
63054e
diff --git a/phc2sys.c b/phc2sys.c
63054e
index 2cd477a..b8f1ea0 100644
63054e
--- a/phc2sys.c
63054e
+++ b/phc2sys.c
63054e
@@ -790,6 +790,16 @@ static int do_loop(struct node *node, int subscriptions)
63054e
 						   node->phc_readings,
63054e
 						   &offset, &ts, &delay) < 0)
63054e
 					return -1;
63054e
+			} else if (node->master->clkid == CLOCK_REALTIME &&
63054e
+				   clock->sysoff_method >= 0) {
63054e
+				/* use reversed sysoff */
63054e
+				if (sysoff_measure(CLOCKID_TO_FD(clock->clkid),
63054e
+						   clock->sysoff_method,
63054e
+						   node->phc_readings,
63054e
+						   &offset, &ts, &delay) < 0)
63054e
+					return -1;
63054e
+				ts += offset;
63054e
+				offset = -offset;
63054e
 			} else {
63054e
 				/* use phc */
63054e
 				if (!read_phc(node->master->clkid, clock->clkid,
0c2424
commit e0580929f451e685d92cd10d80b76f39e9b09a97
0c2424
Author: Richard Cochran <richardcochran@gmail.com>
0c2424
Date:   Tue Dec 24 11:09:34 2019 -0800
0c2424
0c2424
    phc2sys: Fix frequency estimation when synchronizing a PHC to the system clock.
0c2424
    
0c2424
    When synchronizing a PHC to the Linux system clock (CLOCK_REALTIME),
0c2424
    the phc2sys uses the sysoff method, reversing the master and slave
0c2424
    roles.
0c2424
    
0c2424
    The offset between a master clock and a slave clock is given by
0c2424
    
0c2424
        offset = slave_ts - master_ts,
0c2424
    
0c2424
    and the call to sysoff_measure() provides the 'offset' and 'slave_ts'
0c2424
    values.  The needed local time stamp on the 'master' is given by
0c2424
    
0c2424
        master_ts = slave_ts - offset,
0c2424
    
0c2424
    but the code calcuates
0c2424
    
0c2424
        master_ts = slave_ts + offset.
0c2424
    
0c2424
    When passed to the servo, the local time stamp is used to estimate the
0c2424
    frequency offset between the two clocks before starting the main
0c2424
    synchronization loop.  The effect of the bug may be seen with a simple
0c2424
    test.  Here is a sample output with the existing code.
0c2424
    
0c2424
        $ sudo testptp -d /dev/ptp1 -f 62400000
0c2424
        frequency adjustment okay
0c2424
        $ sudo ./phc2sys -m -q -c eth6 -s CLOCK_REALTIME -O0
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        phc2sys[90221.239]: eth6 sys offset 191001318 s0 freq -62400000 delay   5547
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        phc2sys[90222.239]: eth6 sys offset 253380897 s1 freq  +8265884 delay   5507
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        phc2sys[90223.239]: eth6 sys offset  -8301685 s2 freq    -35801 delay   5487
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        phc2sys[90224.239]: eth6 sys offset  -8297136 s2 freq  -2521757 delay   5531
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        phc2sys[90225.239]: eth6 sys offset  -5806117 s2 freq  -2519879 delay   5542
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        phc2sys[90226.239]: eth6 sys offset  -3317009 s2 freq  -1772606 delay   5495
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        phc2sys[90227.240]: eth6 sys offset  -1575231 s2 freq  -1025931 delay   5505
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        phc2sys[90228.240]: eth6 sys offset   -580249 s2 freq   -503518 delay   5524
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        phc2sys[90229.240]: eth6 sys offset   -107770 s2 freq   -205114 delay   5519
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        phc2sys[90230.240]: eth6 sys offset     66298 s2 freq    -63377 delay   5490
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        phc2sys[90230.881]: eth6 sys offset     86942 s2 freq    -22844 delay   5495
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    And this is the output with the bug fix in place.
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        $ sudo testptp -d /dev/ptp1 -f 62400000
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        frequency adjustment okay
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        $ sudo ./phc2sys -m -q -c eth6 -s CLOCK_REALTIME -O0
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        phc2sys[90365.624]: eth6 sys offset 311912675 s0 freq -62400000 delay   5490
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        phc2sys[90366.624]: eth6 sys offset 374292766 s1 freq  -31098 delay   5642
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        phc2sys[90367.624]: eth6 sys offset     -3825 s2 freq  -34923 delay   5617
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        phc2sys[90368.625]: eth6 sys offset         6 s2 freq  -32240 delay   5564
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        phc2sys[90369.625]: eth6 sys offset      1241 s2 freq  -31003 delay   5605
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        phc2sys[90370.625]: eth6 sys offset      1131 s2 freq  -30741 delay   5600
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        phc2sys[90371.625]: eth6 sys offset       801 s2 freq  -30732 delay   5621
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        phc2sys[90372.625]: eth6 sys offset       458 s2 freq  -30834 delay   5640
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        phc2sys[90373.626]: eth6 sys offset       186 s2 freq  -30969 delay   5598
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        phc2sys[90374.626]: eth6 sys offset       134 s2 freq  -30965 delay   5599
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        phc2sys[90375.626]: eth6 sys offset        43 s2 freq  -31016 delay   5595
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        phc2sys[90375.681]: eth6 sys offset       -32 s2 freq  -31078 delay   5541
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    This patch fixes the issue by correcting the calculation of the local
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    time stamp value.
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    Fixes: 8142da41b61f ("phc2sys: Use reversed sysoff when synchronizing to system clock.")
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    Signed-off-by: Richard Cochran <richardcochran@gmail.com>
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    Reported-by: Cliff Spradlin <cspradlin@google.com>
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    Tested-by: Vladimir Oltean <olteanv@gmail.com>
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diff --git a/phc2sys.c b/phc2sys.c
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index 28c657a..c0b7b3d 100644
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--- a/phc2sys.c
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+++ b/phc2sys.c
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@@ -770,8 +770,8 @@ static int do_loop(struct node *node, int subscriptions)
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 						   node->phc_readings,
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 						   &offset, &ts, &delay) < 0)
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 					return -1;
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-				ts += offset;
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 				offset = -offset;
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+				ts += offset;
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 			} else {
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 				/* use phc */
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 				if (!read_phc(node->master->clkid, clock->clkid,