Le mardi 05 juillet 2011 à 08:54 -0700, Dan Magenheimer a écrit : > In working on a kernel project called RAMster* (where RAM on a > remote system may be used for clean page cache pages and for swap > pages), I found I have need for a kernel socket to be used when > in non-preemptible state. I admit to being a networking idiot, > but I have been successfully using the following small patch. > I'm not sure whether I am lucky so far... perhaps more > sockets or larger/different loads will require a lot more > changes (or maybe even make my objective impossible). > So I thought I'd post it for comment. I'd appreciate > any thoughts or suggestions. > > Thanks, > Dan > > * http://events.linuxfoundation.org/events/linuxcon/magenheimer > > diff -Napur linux-2.6.37/net/core/sock.c linux-2.6.37-ramster/net/core/sock.c > --- linux-2.6.37/net/core/sock.c 2011-07-03 19:14:52.267853088 -0600 > +++ linux-2.6.37-ramster/net/core/sock.c 2011-07-03 19:10:04.340980799 -0600 > @@ -1587,6 +1587,14 @@ static void __lock_sock(struct sock *sk) > __acquires(&sk->sk_lock.slock) > { > DEFINE_WAIT(wait); > + if (!preemptible()) { > + while (sock_owned_by_user(sk)) { > + spin_unlock_bh(&sk->sk_lock.slock); > + cpu_relax(); > + spin_lock_bh(&sk->sk_lock.slock); > + } > + return; > + } Hmm, was this tested on UP machine ? > > for (;;) { > prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, > @@ -1623,7 +1631,8 @@ static void __release_sock(struct sock * > * This is safe to do because we've taken the backlog > * queue private: > */ > - cond_resched_softirq(); > + if (preemptible()) > + cond_resched_softirq(); > skb = next; > } while (skb != NULL); -- 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=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>