On Monday, June 22, 2015 09:13:23 Sven Eckelmann wrote:
The 64-bit gw_factor is divided by BATADV_TQ_LOCAL_WINDOW_SIZE ** 2 * 64. But the rest of the calculation has nothing to do with the tq window size end therefore the calculation is just (tmp_gw_factor / (64 ** 3)).
The problem with 64 bit div is that it doesn't work on systems without native 64 bit div support. It has to be emulated using do_div or div_u64. The change in f63c54bba31d ("batman-adv: Avoid u32 overflow during gateway select") only compiled on such systems because the compiler converted the div to a (tmp_gw_factor >> 18). Making this explicit avoids having build problems in the future when BATADV_TQ_LOCAL_WINDOW_SIZE is changed in such a way that (BATADV_TQ_LOCAL_WINDOW_SIZE ** 2 * 64) is not a power of two.
Signed-off-by: Sven Eckelmann sven@narfation.org
gateway_client.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
Applied in revision 013aab3.
Thanks, Marek