On Wed, 2022-07-27 at 10:46 +0800, Yu Zhe wrote: > time_is_before_jiffies deals with timer wrapping correctly. > > Signed-off-by: Yu Zhe <yuzhe@xxxxxxxxxxxx> > --- > net/decnet/dn_route.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c > index 552a53f1d5d0..0a4bed0bc2e3 100644 > --- a/net/decnet/dn_route.c > +++ b/net/decnet/dn_route.c > @@ -201,7 +201,7 @@ static void dn_dst_check_expire(struct timer_list *unused) > } > spin_unlock(&dn_rt_hash_table[i].lock); > > - if ((jiffies - now) > 0) > + if (time_is_before_jiffies(now)) Uhmm... it looks like the wrap-around condition can happen only in theory: 'now' is initialized just before entering this loop, and we will break as soon as jiffies increment. The wrap-around could happen only if a single iteration of the loop takes more than LONG_MAX jiffies. If that happens, we have a completely different kind of much more serious problem, I think ;) So this change is mostly for core readability's sake. I personally find more readable: if (jiffies != now) Cheers, Paolo p.s. given the above I guess this is for the net-next tree, right?
