systemd/0094-timesyncd-allow-two-mi...

95 lines
3.7 KiB
Diff

From 8269ab5ca37ca93f52ec1766d673e85887aa0ebe Mon Sep 17 00:00:00 2001
From: Michal Schmidt <mschmidt@redhat.com>
Date: Wed, 10 Sep 2014 19:55:59 +0200
Subject: [PATCH] timesyncd: allow two missed replies before reselecting server
Upstream commit:
commit e8206972be6a7ebeb198cd0d400bc7a94a6a5fc5
Author: Miroslav Lichvar <mlichvar@redhat.com>
Date: Tue Sep 2 14:29:51 2014 +0200
timesyncd: allow two missed replies before reselecting server
After receiving a reply from the server, allow two missed replies before
switching to another server to avoid unnecessary clock hopping when
packets are getting lost in the network.
Conflicts:
src/timesync/timesyncd-manager.c
---
src/timesync/timesyncd.c | 27 ++++++++++++++++++---------
src/timesync/timesyncd.h | 1 +
2 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/src/timesync/timesyncd.c b/src/timesync/timesyncd.c
index 589c5ec521..7470f4db97 100644
--- a/src/timesync/timesyncd.c
+++ b/src/timesync/timesyncd.c
@@ -94,6 +94,9 @@
/* Maximum acceptable root distance in seconds. */
#define NTP_MAX_ROOT_DISTANCE 5.0
+/* Maximum number of missed replies before selecting another source. */
+#define NTP_MAX_MISSED_REPLIES 2
+
/*
* "NTP timestamps are represented as a 64-bit unsigned fixed-point number,
* in seconds relative to 0h on 1 January 1900."
@@ -277,15 +280,18 @@ static int manager_send_request(Manager *m) {
return r;
}
- r = sd_event_add_time(
- m->event,
- &m->event_timeout,
- clock_boottime_or_monotonic(),
- now(clock_boottime_or_monotonic()) + TIMEOUT_USEC, 0,
- manager_timeout, m);
- if (r < 0) {
- log_error("Failed to arm timeout timer: %s", strerror(-r));
- return r;
+ m->missed_replies++;
+ if (m->missed_replies > NTP_MAX_MISSED_REPLIES) {
+ r = sd_event_add_time(
+ m->event,
+ &m->event_timeout,
+ clock_boottime_or_monotonic(),
+ now(clock_boottime_or_monotonic()) + TIMEOUT_USEC, 0,
+ manager_timeout, m);
+ if (r < 0) {
+ log_error("Failed to arm timeout timer: %s", strerror(-r));
+ return r;
+ }
}
return 0;
@@ -627,6 +633,8 @@ static int manager_receive_response(sd_event_source *source, int fd, uint32_t re
return 0;
}
+ m->missed_replies = 0;
+
/* check our "time cookie" (we just stored nanoseconds in the fraction field) */
if (be32toh(ntpmsg.origin_time.sec) != m->trans_time.tv_sec + OFFSET_1900_1970 ||
be32toh(ntpmsg.origin_time.frac) != m->trans_time.tv_nsec) {
@@ -791,6 +799,7 @@ static int manager_begin(Manager *m) {
assert_return(m->current_server_name, -EHOSTUNREACH);
assert_return(m->current_server_address, -EHOSTUNREACH);
+ m->missed_replies = NTP_MAX_MISSED_REPLIES;
m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
sockaddr_pretty(&m->current_server_address->sockaddr.sa, m->current_server_address->socklen, true, &pretty);
diff --git a/src/timesync/timesyncd.h b/src/timesync/timesyncd.h
index 04d83f0cc9..bcd14f71f6 100644
--- a/src/timesync/timesyncd.h
+++ b/src/timesync/timesyncd.h
@@ -61,6 +61,7 @@ struct Manager {
ServerName *current_server_name;
ServerAddress *current_server_address;
int server_socket;
+ int missed_replies;
uint64_t packet_count;
sd_event_source *event_timeout;