On Tue, Apr 18, 2017 at 12:45 PM, Eric Dumazet <eduma...@google.com> wrote: > When a RST packet is processed, we send two wakeup events to interested > polling users. > > First one by a sk->sk_error_report(sk) from tcp_reset(), > followed by a sk->sk_state_change(sk) from tcp_done(). > > Depending on machine load and luck, poll() can either return POLLERR, > or POLLIN|POLLOUT|POLLERR|POLLHUP (this happens on 99 % of the cases) > > This is probably fine, but we can avoid the confusion by reordering > things so that we have more TCP fields updated before the first wakeup. > > This might even allow us to remove some barriers we added in the past. > > Signed-off-by: Eric Dumazet <eduma...@google.com>
Acked-by: Soheil Hassas Yeganeh <soh...@google.com> > --- > net/ipv4/tcp_input.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c > index > a5838858c362cd3270296001ceaae341e9e9bf01..37e2aa925f62395cfb48145cd3a76b6afebb64b1 > 100644 > --- a/net/ipv4/tcp_input.c > +++ b/net/ipv4/tcp_input.c > @@ -4008,10 +4008,10 @@ void tcp_reset(struct sock *sk) > /* This barrier is coupled with smp_rmb() in tcp_poll() */ > smp_wmb(); > > + tcp_done(sk); > + > if (!sock_flag(sk, SOCK_DEAD)) > sk->sk_error_report(sk); > - > - tcp_done(sk); > } > > /* > -- > 2.12.2.762.g0e3151a226-goog > Thanks, Eric. Nice improvement!
