diff options
| author | Denys Vlasenko <vda.linux@googlemail.com> | 2025-10-11 23:48:04 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2025-10-11 23:48:04 +0200 |
| commit | 3ff3cb483db4165a6d1d4d05bb1f957b4fa5a9b4 (patch) | |
| tree | 8bf344747b5e1e6eb0cf731566f29000fddad16c | |
| parent | 3621595939e43a831d66f6b757d4f410029bff95 (diff) | |
ntpd: set tmx.maxerror properly - avoid STA_UNSYNC
function old new delta
update_local_clock 872 951 +79
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
| -rw-r--r-- | networking/ntpd.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/networking/ntpd.c b/networking/ntpd.c index dd0a9c91f..efe9f5326 100644 --- a/networking/ntpd.c +++ b/networking/ntpd.c @@ -1645,7 +1645,7 @@ update_local_clock(peer_t *p) /* 65536 is one ppm */ tmx.freq = G.discipline_freq_drift * 65536e6; #endif - tmx.modes = ADJ_OFFSET | ADJ_STATUS | ADJ_TIMECONST;// | ADJ_MAXERROR | ADJ_ESTERROR; + tmx.modes = ADJ_OFFSET | ADJ_STATUS | ADJ_TIMECONST | ADJ_MAXERROR | ADJ_ESTERROR; tmx.offset = (long)(offset * 1000000); /* usec */ if (SLEW_THRESHOLD < STEP_THRESHOLD) { @@ -1738,16 +1738,23 @@ update_local_clock(peer_t *p) if (tmx.constant < 0) tmx.constant = 0; - //tmx.esterror = (uint32_t)(clock_jitter * 1e6); - //tmx.maxerror = (uint32_t)((sys_rootdelay / 2 + sys_rootdisp) * 1e6); + /* For ADJ_MAXERROR and ADJ_ESTERROR: */ + /* kernel increments this by 500us each second, sets STA_UNSYNC if exceeds 16 seconds: */ + tmx.maxerror = (uint32_t)((G.rootdelay / 2 + G.rootdisp) * 1000000.0); + /* (without ADJ_MAXERROR, time adjustment still works, but kernel uses + * conservative maxerror value and quickly sets STA_UNSYNC) + */ + /* esterror is not used by kernel, presumably may be used by other programs reading adjtimex result: */ + tmx.esterror = (uint32_t)(G.discipline_jitter * 1000000.0); + rc = adjtimex(&tmx); if (rc < 0) bb_simple_perror_msg_and_die("adjtimex"); /* NB: here kernel returns constant == G.poll_exp, not == G.poll_exp - 4. * Not sure why. Perhaps it is normal. */ - VERB4 bb_error_msg("adjtimex:%d freq:%ld offset:%+ld status:0x%x", - rc, (long)tmx.freq, (long)tmx.offset, tmx.status); + VERB4 bb_error_msg("adjtimex:%d freq:%ld offset:%+ld esterror:%ld maxerror:%ld status:0x%x", + rc, (long)tmx.freq, (long)tmx.offset, (long)tmx.esterror, (long)tmx.maxerror, tmx.status); G.kernel_freq_drift = tmx.freq / 65536; VERB2 bb_error_msg("update from:%s offset:%+f delay:%f jitter:%f clock drift:%+.3fppm tc:%d", p->p_dotted, |