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authorDenys Vlasenko <vda.linux@googlemail.com>2010-01-11 00:31:59 (GMT)
committer Denys Vlasenko <vda.linux@googlemail.com>2010-01-11 00:31:59 (GMT)
commit12628b77970b46290ed75ecae55afe65297b3e35 (patch)
tree4c2da785709fb5f8d0a19d6573d5ad7efc7ed1a8
parent725b5a387a392f6282756c649adf411e30535eb5 (diff)
downloadbusybox-12628b77970b46290ed75ecae55afe65297b3e35.tar.gz
busybox-12628b77970b46290ed75ecae55afe65297b3e35.tar.bz2
ntpd: expose more data to the script; more eagerly drop to lower poll
function old new delta run_script 340 395 +55 recv_and_process_peer_pkt 817 869 +52 passwd_main 1027 1058 +31 ntpd_main 845 855 +10 update_local_clock 853 823 -30 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 4/1 up/down: 148/-30) Total: 118 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--networking/ntpd.c72
1 files changed, 46 insertions, 26 deletions
diff --git a/networking/ntpd.c b/networking/ntpd.c
index c28d768..092c444 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -49,24 +49,26 @@
#define RETRY_INTERVAL 5 /* on error, retry in N secs */
#define RESPONSE_INTERVAL 15 /* wait for reply up to N secs */
-#define FREQ_TOLERANCE 0.000015 /* % frequency tolerance (15 PPM) */
-#define BURSTPOLL 0
-#define MINPOLL 4 /* % minimum poll interval (6: 64 s) */
-#define MAXPOLL 12 /* % maximum poll interval (12: 1.1h, 17: 36.4h) (was 17) */
-#define MINDISP 0.01 /* % minimum dispersion (s) */
-#define MAXDISP 16 /* maximum dispersion (s) */
-#define MAXSTRAT 16 /* maximum stratum (infinity metric) */
-#define MAXDIST 1 /* % distance threshold (s) */
-#define MIN_SELECTED 1 /* % minimum intersection survivors */
-#define MIN_CLUSTERED 3 /* % minimum cluster survivors */
-
-#define MAXDRIFT 0.000500 /* frequency drift we can correct (500 PPM) */
-
/* Clock discipline parameters and constants */
#define STEP_THRESHOLD 0.128 /* step threshold (s) */
#define WATCH_THRESHOLD 150 /* stepout threshold (s). std ntpd uses 900 (11 mins (!)) */
/* NB: set WATCH_THRESHOLD to ~60 when debugging to save time) */
-#define PANIC_THRESHOLD 1000 /* panic threshold (s) */
+//UNUSED: #define PANIC_THRESHOLD 1000 /* panic threshold (s) */
+
+#define FREQ_TOLERANCE 0.000015 /* frequency tolerance (15 PPM) */
+#define BURSTPOLL 0 /* initial poll */
+#define MINPOLL 4 /* minimum poll interval (6: 64 s) */
+#define BIGPOLL 10 /* drop to lower poll at any trouble (10: 17 min) */
+#define MAXPOLL 12 /* maximum poll interval (12: 1.1h, 17: 36.4h) (was 17) */
+#define POLLDOWN_OFFSET (STEP_THRESHOLD / 3) /* actively lower poll when we see such big offsets */
+#define MINDISP 0.01 /* minimum dispersion (s) */
+#define MAXDISP 16 /* maximum dispersion (s) */
+#define MAXSTRAT 16 /* maximum stratum (infinity metric) */
+#define MAXDIST 1 /* distance threshold (s) */
+#define MIN_SELECTED 1 /* minimum intersection survivors */
+#define MIN_CLUSTERED 3 /* minimum cluster survivors */
+
+#define MAXDRIFT 0.000500 /* frequency drift we can correct (500 PPM) */
/* Poll-adjust threshold.
* When we see that offset is small enough compared to discipline jitter,
@@ -686,10 +688,10 @@ send_query_to_peer(peer_t *p)
}
-static void run_script(const char *action)
+static void run_script(const char *action, double offset)
{
char *argv[3];
- char *env1, *env2, *env3;
+ char *env1, *env2, *env3, *env4;
if (!G.script_name)
return;
@@ -706,9 +708,12 @@ static void run_script(const char *action)
putenv(env2);
env3 = xasprintf("%s=%u", "poll_interval", 1 << G.poll_exp);
putenv(env3);
+ env4 = xasprintf("%s=%f", "offset", offset);
+ putenv(env4);
/* Other items of potential interest: selected peer,
* rootdelay, reftime, rootdisp, refid, ntp_status,
- * last_update_offset, last_update_recv_time, discipline_jitter
+ * last_update_offset, last_update_recv_time, discipline_jitter,
+ * how many peers have reachable_bits = 0?
*/
/* Don't want to wait: it may run hwclock --systohc, and that
@@ -719,9 +724,11 @@ static void run_script(const char *action)
unsetenv("stratum");
unsetenv("freq_drift_ppm");
unsetenv("poll_interval");
+ unsetenv("offset");
free(env1);
free(env2);
free(env3);
+ free(env4);
G.last_script_run = G.cur_time;
}
@@ -1095,10 +1102,14 @@ update_local_clock(peer_t *p)
abs_offset = fabs(offset);
+#if 0
+ /* If needed, -S script can detect this by looking at $offset
+ * env var and kill parent */
/* If the offset is too large, give up and go home */
if (abs_offset > PANIC_THRESHOLD) {
bb_error_msg_and_die("offset %f far too big, exiting", offset);
}
+#endif
/* If this is an old update, for instance as the result
* of a system peer change, avoid it. We never use
@@ -1185,7 +1196,7 @@ update_local_clock(peer_t *p)
G.poll_exp = MINPOLL;
G.stratum = MAXSTRAT;
- run_script("step");
+ run_script("step", offset);
if (G.discipline_state == STATE_NSET) {
set_new_values(STATE_FREQ, /*offset:*/ 0, recv_time);
@@ -1274,7 +1285,7 @@ update_local_clock(peer_t *p)
}
if (G.stratum != p->lastpkt_stratum + 1) {
G.stratum = p->lastpkt_stratum + 1;
- run_script("stratum");
+ run_script("stratum", offset);
}
}
@@ -1371,10 +1382,8 @@ update_local_clock(peer_t *p)
tmx.freq, tmx.offset, tmx.constant, tmx.status);
}
#endif
- if (G.kernel_freq_drift != tmx.freq / 65536) {
- G.kernel_freq_drift = tmx.freq / 65536;
- VERB2 bb_error_msg("kernel clock drift: %ld ppm", G.kernel_freq_drift);
- }
+ G.kernel_freq_drift = tmx.freq / 65536;
+ VERB2 bb_error_msg("update offset:%f, clock drift:%ld ppm", G.last_update_offset, G.kernel_freq_drift);
return 1; /* "ok to increase poll interval" */
}
@@ -1538,9 +1547,19 @@ recv_and_process_peer_pkt(peer_t *p)
rc = -1;
if (q) {
rc = 0;
- if (!(option_mask32 & OPT_w))
+ if (!(option_mask32 & OPT_w)) {
rc = update_local_clock(q);
+ /* If drift is dangerously large, immediately
+ * drop poll interval one step down.
+ */
+ if (q->filter_offset < -POLLDOWN_OFFSET
+ || q->filter_offset > POLLDOWN_OFFSET
+ ) {
+ goto poll_down;
+ }
+ }
}
+ /* else: no peer selected, rc = -1: we want to poll more often */
if (rc != 0) {
/* Adjust the poll interval by comparing the current offset
@@ -1572,7 +1591,8 @@ recv_and_process_peer_pkt(peer_t *p)
}
} else {
G.polladj_count -= G.poll_exp * 2;
- if (G.polladj_count < -POLLADJ_LIMIT) {
+ if (G.polladj_count < -POLLADJ_LIMIT || G.poll_exp >= BIGPOLL) {
+ poll_down:
G.polladj_count = 0;
if (G.poll_exp > MINPOLL) {
llist_t *item;
@@ -1910,7 +1930,7 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
&& G.cur_time - G.last_script_run > 11*60
) {
/* Useful for updating battery-backed RTC and such */
- run_script("periodic");
+ run_script("periodic", G.last_update_offset);
gettime1900d(); /* sets G.cur_time */
}
continue;