From 3e78f6f955ebdc010bb0b8f78622bf701e594b69 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 9 Feb 2014 15:35:04 +0100 Subject: [PATCH] htpd: trivial simplification in random interval selection function old new delta poll_interval 57 52 -5 Signed-off-by: Denys Vlasenko --- networking/ntpd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/networking/ntpd.c b/networking/ntpd.c index 03fe448ca..bf8ef0a89 100644 --- a/networking/ntpd.c +++ b/networking/ntpd.c @@ -1660,13 +1660,14 @@ retry_interval(void) static unsigned poll_interval(int exponent) { - unsigned interval, r; + unsigned interval, r, mask; exponent = G.poll_exp + exponent; if (exponent < 0) exponent = 0; interval = 1 << exponent; + mask = ((interval-1) >> 4) | 1; r = random(); - interval += ((r & (interval-1)) >> 4) + ((r >> 8) & 1); /* + 1/16 of interval, max */ + interval += r & mask; /* ~ random(0..1) * interval/16 */ VERB4 bb_error_msg("chose poll interval:%u (poll_exp:%d exp:%d)", interval, G.poll_exp, exponent); return interval; } -- 2.25.1