On Sat, 2011-08-06 at 16:44 +0800, Wu Fengguang wrote:
> + pos_bw = bw * pos_ratio >> BANDWIDTH_CALC_SHIFT;
> + pos_bw++; /* this avoids bdi->dirty_ratelimit get stuck in 0 */
> +
> + pos_ratio *= bdi->avg_write_bandwidth;
> + do_div(pos_ratio, dirty_bw | 1);
> + ref_bw = bw * pos_ratio >> BANDWIDTH_CALC_SHIFT;
when written out that results in:
bw * pos_ratio * bdi->avg_write_bandwidth
ref_bw = -----------------------------------------
dirty_bw
which would suggest you write it like:
ref_bw = div_u64((u64)pos_bw * bdi->avg_write_bandwidth, dirty_bw | 1);
since pos_bw is already bw * pos_ratio per the above.
Or am I missing something?
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href