On Tue, Sep 27, 2016 at 08:39:59AM -0700, Eric Dumazet wrote: ... > > + } > > + if (sk && !atomic_inc_not_zero(&sk->sk_refcnt)) > > + sk = NULL; > > Minor detail, but note that raw sockets do not use rcu (yet) > > Since you have read_lock(&hashinfo->lock), no writer can suddenly change > sk->sk_refcnt to a zero value. > > Therefore, a mere "sock_hold(sk)" should be enough to get a reference on > the socket. > > Using atomic_inc_not_zero() also works, but might distract/confuse the > next guy trying to understand this code ;)
Oh, I see. Thanks Eric! I'll update the patch (hopefully tonight) and send it out (need to finish urgent task atm).