For now, only CLOCK_REALTIME can be UTC. This may stay this way forever but
now we have a clean separation between codepaths where CLOCK_REALTIME is
required and codepaths any UTC clock should take.
The main motiviation behind this change is removal of sync_offset_direction.
It has to be computed on the fly based on the source and destination when we
have multiple clocks supported and automatic following of ptp4l state
changes implemented.
Signed-off-by: Jiri Benc <jb...@redhat.com>
---
phc2sys.c | 60 +++++++++++++++++++++++++++++-------------------------------
1 files changed, 29 insertions(+), 31 deletions(-)
diff --git a/phc2sys.c b/phc2sys.c
index 825d7328af15..6c86b4d9f028 100644
--- a/phc2sys.c
+++ b/phc2sys.c
@@ -130,6 +130,7 @@ struct clock {
LIST_ENTRY(clock) list;
clockid_t clkid;
int sysoff_supported;
+ int is_utc;
struct servo *servo;
enum servo_state servo_state;
const char *source_label;
@@ -146,7 +147,7 @@ struct node {
int phc_readings;
double phc_interval;
int sync_offset;
- int sync_offset_direction;
+ int forced_sync_offset;
int leap;
int leap_set;
int kernel_leap;
@@ -161,6 +162,15 @@ static int update_sync_offset(struct node *node);
static int clock_handle_leap(struct node *node, struct clock *clock,
int64_t offset, uint64_t ts, int do_leap);
+static int64_t get_sync_offset(struct node *node, struct clock *src)
+{
+ int direction = node->forced_sync_offset;
+
+ if (!direction)
+ direction = node->master->is_utc - src->is_utc;
+ return (int64_t)node->sync_offset * NS_PER_SEC * direction;
+}
+
static void update_clock_stats(struct clock *clock, unsigned int max_count,
int64_t offset, double freq, int64_t delay)
{
@@ -206,9 +216,7 @@ static void update_clock(struct node *node, struct clock
*clock,
if (clock_handle_leap(node, clock, offset, ts, do_leap))
return;
- if (node->sync_offset_direction)
- offset += node->sync_offset * NS_PER_SEC *
- node->sync_offset_direction;
+ offset += get_sync_offset(node, clock);
if (clock->sanity_check && clockcheck_sample(clock->sanity_check, ts))
servo_reset(clock->servo);
@@ -290,7 +298,7 @@ static int do_pps_loop(struct node *node, struct clock
*clock, int fd)
if (src == CLOCK_INVALID) {
/* The sync offset can't be applied with PPS alone. */
- node->sync_offset_direction = 0;
+ node->sync_offset = 0;
} else {
enable_pps_output(node->master->clkid);
}
@@ -558,15 +566,14 @@ static int clock_handle_leap(struct node *node, struct
clock *clock,
if (!node->leap && !do_leap)
return 0;
- if (clock->clkid != CLOCK_REALTIME &&
- node->master->clkid != CLOCK_REALTIME)
+ if (clock->is_utc == node->master->is_utc)
return 0;
/* If the system clock is the master clock, get a time stamp from
it, as it is the clock which will include the leap second. */
- if (node->master->clkid == CLOCK_REALTIME) {
+ if (node->master->is_utc) {
struct timespec tp;
- if (clock_gettime(CLOCK_REALTIME, &tp)) {
+ if (clock_gettime(node->master->clkid, &tp)) {
pr_err("failed to read clock: %m");
return -1;
}
@@ -575,11 +582,8 @@ static int clock_handle_leap(struct node *node, struct
clock *clock,
/* If the clock will be stepped, the time stamp has to be the
target time. Ignore possible 1 second error in UTC offset. */
- if (clock->clkid == CLOCK_REALTIME &&
- clock->servo_state == SERVO_UNLOCKED) {
- ts -= offset + node->sync_offset * NS_PER_SEC *
- node->sync_offset_direction;
- }
+ if (clock->is_utc && clock->servo_state == SERVO_UNLOCKED)
+ ts -= get_sync_offset(node, clock);
/* Suspend clock updates in the last second before midnight. */
if (is_utc_ambiguous(ts)) {
@@ -610,10 +614,12 @@ static int clock_add(struct node *node, clockid_t clkid)
c->clkid = clkid;
c->servo_state = SERVO_UNLOCKED;
- if (c->clkid == CLOCK_REALTIME)
+ if (c->clkid == CLOCK_REALTIME) {
c->source_label = "sys";
- else
+ c->is_utc = 1;
+ } else {
c->source_label = "phc";
+ }
if (node->stats_max_count > 0) {
c->offset_stats = stats_create();
@@ -698,7 +704,7 @@ int main(int argc, char *argv[])
clockid_t src = CLOCK_INVALID;
clockid_t dst = CLOCK_REALTIME;
int c, domain_number = 0, pps_fd = -1;
- int r, wait_sync = 0, forced_sync_offset = 0;
+ int r, wait_sync = 0;
int print_level = LOG_INFO, use_syslog = 1, verbose = 0;
double phc_rate;
struct node node = {
@@ -779,8 +785,7 @@ int main(int argc, char *argv[])
if (get_arg_val_i(c, optarg, &node.sync_offset,
INT_MIN, INT_MAX))
return -1;
- node.sync_offset_direction = -1;
- forced_sync_offset = 1;
+ node.forced_sync_offset = -1;
break;
case 'L':
if (get_arg_val_i(c, optarg, &node.sanity_freq_limit,
0, INT_MAX))
@@ -841,7 +846,7 @@ int main(int argc, char *argv[])
goto bad_usage;
}
- if (!wait_sync && !forced_sync_offset) {
+ if (!wait_sync && !node.forced_sync_offset) {
fprintf(stderr,
"time offset must be specified using -w or -O\n");
goto bad_usage;
@@ -870,24 +875,17 @@ int main(int argc, char *argv[])
pr_notice("Waiting for ptp4l...");
}
- if (!forced_sync_offset) {
+ if (!node.forced_sync_offset) {
r = run_pmc_get_utc_offset(&node, 1000);
if (r <= 0) {
pr_err("failed to get UTC offset");
return -1;
}
-
- if (src != CLOCK_REALTIME &&
- dst == CLOCK_REALTIME)
- node.sync_offset_direction = 1;
- else if (src == CLOCK_REALTIME &&
- dst != CLOCK_REALTIME)
- node.sync_offset_direction = -1;
- else
- node.sync_offset_direction = 0;
}
- if (forced_sync_offset || !node.sync_offset_direction)
+ if (node.forced_sync_offset ||
+ (src != CLOCK_REALTIME && dst != CLOCK_REALTIME) ||
+ src == CLOCK_INVALID)
close_pmc(&node);
}
--
1.7.6.5
------------------------------------------------------------------------------
Learn Graph Databases - Download FREE O'Reilly Book
"Graph Databases" is the definitive new guide to graph databases and their
applications. Written by three acclaimed leaders in the field,
this first edition is now available. Download your free book today!
http://p.sf.net/sfu/13534_NeoTech
_______________________________________________
Linuxptp-devel mailing list
Linuxptp-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
