141 lines
4.7 KiB
Diff
141 lines
4.7 KiB
Diff
From 0cb3bd52e6dd3680aa900045d3c837d1098d8da8 Mon Sep 17 00:00:00 2001
|
|
From: cwalker <cole.walker@windriver.com>
|
|
Date: Tue, 20 Feb 2024 17:25:17 +0000
|
|
Subject: [PATCH 58/58] Implement logic to skip updates with offset spike.
|
|
|
|
This change allows ts2phc to be configured to ignore timing updates that
|
|
have a large offset spike in order to mitigate the resulting timing
|
|
skew.
|
|
|
|
In some circumstances on realtime systems with high CPU load, the
|
|
timestamp consumed by ts2phc can be delayed in reaching ts2phc and
|
|
results in the offset calculation attempting to speed the clock up by a
|
|
large margin.
|
|
|
|
This change causes ts2phc to ignore updates that would greatly skew the
|
|
clock when ts2phc is already in a synchronized state.
|
|
|
|
The global configuration option "max_phc_update_skip_cnt" is provided to
|
|
allow users to specify how many consecutive offset spike incidents will
|
|
be ignored before adjusting the clock. The default value is 120. The
|
|
behaviour can be disabled by setting max_phc_update_skip_cnt to 0.
|
|
|
|
This code is ported from a proposed upstream patch found here:
|
|
https://sourceforge.net/p/linuxptp/mailman/message/44114092/
|
|
|
|
Signed-off-by: cwalker <cole.walker@windriver.com>
|
|
---
|
|
config.c | 1 +
|
|
ts2phc.c | 3 +++
|
|
ts2phc_slave.c | 26 ++++++++++++++++++++++++--
|
|
3 files changed, 28 insertions(+), 2 deletions(-)
|
|
diff --git a/config.c b/config.c
|
|
index ef17463..b53d8f4 100644
|
|
--- a/config.c
|
|
+++ b/config.c
|
|
@@ -347,6 +347,7 @@ struct config_item config_tab[] = {
|
|
GLOB_ITEM_INT("verbose", 0, 0, 1),
|
|
GLOB_ITEM_INT("write_phase_mode", 0, 0, 1),
|
|
GLOB_ITEM_INT("default_sync", 1, 0, 1),
|
|
+ PORT_ITEM_INT("max_phc_update_skip_cnt", 120, 0, 14400),
|
|
};
|
|
|
|
static struct unicast_master_table *current_uc_mtab;
|
|
diff --git a/ts2phc.c b/ts2phc.c
|
|
index 2342858..a59dc5f 100644
|
|
--- a/ts2phc.c
|
|
+++ b/ts2phc.c
|
|
@@ -15,6 +15,8 @@
|
|
#include "ts2phc_slave.h"
|
|
#include "version.h"
|
|
|
|
+int max_phc_update_skip_count;
|
|
+
|
|
struct interface {
|
|
STAILQ_ENTRY(interface) list;
|
|
};
|
|
@@ -146,6 +148,7 @@ int main(int argc, char *argv[])
|
|
print_set_verbose(config_get_int(cfg, NULL, "verbose"));
|
|
print_set_syslog(config_get_int(cfg, NULL, "use_syslog"));
|
|
print_set_level(config_get_int(cfg, NULL, "logging_level"));
|
|
+ max_phc_update_skip_count = config_get_int(cfg, NULL, "max_phc_update_skip_cnt");
|
|
|
|
STAILQ_FOREACH(iface, &cfg->interfaces, list) {
|
|
if (1 == config_get_int(cfg, interface_name(iface), "ts2phc.master")) {
|
|
diff --git a/ts2phc_slave.c b/ts2phc_slave.c
|
|
index 749efe5..126c502 100644
|
|
--- a/ts2phc_slave.c
|
|
+++ b/ts2phc_slave.c
|
|
@@ -29,6 +29,8 @@
|
|
#define SAMPLE_WEIGHT 1.0
|
|
#define SERVO_SYNC_INTERVAL 1.0
|
|
|
|
+extern int max_phc_update_skip_count;
|
|
+
|
|
struct ts2phc_slave {
|
|
char *name;
|
|
STAILQ_ENTRY(ts2phc_slave) list;
|
|
@@ -42,6 +44,8 @@ struct ts2phc_slave {
|
|
clockid_t clk;
|
|
int no_adj;
|
|
int fd;
|
|
+ int max_offset_skip_count;
|
|
+ int current_offset_skip_count;
|
|
};
|
|
|
|
struct ts2phc_slave_array {
|
|
@@ -218,6 +222,9 @@ static struct ts2phc_slave *ts2phc_slave_create(struct config *cfg, const char *
|
|
if (ts2phc_slave_clear_fifo(slave)) {
|
|
goto no_ext_ts;
|
|
}
|
|
+ slave->max_offset_skip_count = max_phc_update_skip_count;
|
|
+ slave->current_offset_skip_count = 0;
|
|
+ pr_debug("PHC slave %s has skip cnt %d", device, slave->max_offset_skip_count);
|
|
|
|
return slave;
|
|
no_ext_ts:
|
|
@@ -275,6 +282,18 @@ static int ts2phc_slave_event(struct ts2phc_slave *slave,
|
|
return 0;
|
|
}
|
|
|
|
+ if ((slave->state == SERVO_LOCKED) || (slave->state == SERVO_LOCKED_STABLE)) {
|
|
+ if (llabs(offset) >= NS_PER_SEC / 2) {
|
|
+ if (slave->current_offset_skip_count < slave->max_offset_skip_count) {
|
|
+ pr_debug("Offset spike detected. Skip current PHC update %s offset %10" PRId64 " s%d freq %+7.0f",
|
|
+ slave->name, offset, slave->state, adj);
|
|
+ slave->current_offset_skip_count++;
|
|
+ pr_debug("Current skip count: %i", slave->current_offset_skip_count);
|
|
+ return 0;
|
|
+ }
|
|
+ }
|
|
+ }
|
|
+
|
|
adj = servo_sample(slave->servo, offset, extts_ts,
|
|
SAMPLE_WEIGHT, &slave->state);
|
|
|
|
@@ -290,6 +309,9 @@ static int ts2phc_slave_event(struct ts2phc_slave *slave,
|
|
break;
|
|
case SERVO_LOCKED:
|
|
case SERVO_LOCKED_STABLE:
|
|
+ if (llabs(offset) < 500) {
|
|
+ slave->current_offset_skip_count = 0;
|
|
+ }
|
|
clockadj_set_freq(slave->clk, -adj);
|
|
break;
|
|
}
|
|
@@ -336,10 +358,10 @@ static enum extts_result ts2phc_slave_offset(struct ts2phc_slave *slave,
|
|
*local_ts = event_ns + slave->correction;
|
|
|
|
pr_debug("%s extts index %u at %lld.%09u corr %d src %" PRIi64
|
|
- ".%ld diff %" PRId64,
|
|
+ ".%ld diff %" PRId64 " servo state %d",
|
|
slave->name, event.index, event.t.sec, event.t.nsec,
|
|
slave->correction,
|
|
- (int64_t) source_ts.tv_sec, source_ts.tv_nsec, *offset);
|
|
+ (int64_t) source_ts.tv_sec, source_ts.tv_nsec, *offset, slave->state);
|
|
|
|
return EXTTS_OK;
|
|
}
|
|
--
|
|
2.30.2
|