function old new delta
poll_interval 57 52 -5
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
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;
}