| Message ID | 547E6832.4070403@cn.fujitsu.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, 2014-12-03 at 09:32 +0800, Duan Jiong wrote: > xchg is atomic, so there is no necessary to use spin_lock/spin_unlock > to protect it. > > Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> > --- > net/ipv6/ipv6_sockglue.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c > index e1a9583..92ca907 100644 > --- a/net/ipv6/ipv6_sockglue.c > +++ b/net/ipv6/ipv6_sockglue.c > @@ -112,9 +112,7 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk, > } > opt = xchg(&inet6_sk(sk)->opt, opt); > } else { > - spin_lock(&sk->sk_dst_lock); > opt = xchg(&inet6_sk(sk)->opt, opt); > - spin_unlock(&sk->sk_dst_lock); > } > sk_dst_reset(sk); > Why keeping 2 copies of opt = xchg(&inet6_sk(sk)->opt, opt); then ? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/03/2014 09:57 AM, Eric Dumazet wrote: > On Wed, 2014-12-03 at 09:32 +0800, Duan Jiong wrote: >> xchg is atomic, so there is no necessary to use spin_lock/spin_unlock >> to protect it. >> >> Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> >> --- >> net/ipv6/ipv6_sockglue.c | 2 -- >> 1 file changed, 2 deletions(-) >> >> diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c >> index e1a9583..92ca907 100644 >> --- a/net/ipv6/ipv6_sockglue.c >> +++ b/net/ipv6/ipv6_sockglue.c >> @@ -112,9 +112,7 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk, >> } >> opt = xchg(&inet6_sk(sk)->opt, opt); >> } else { >> - spin_lock(&sk->sk_dst_lock); >> opt = xchg(&inet6_sk(sk)->opt, opt); >> - spin_unlock(&sk->sk_dst_lock); >> } >> sk_dst_reset(sk); >> > > Why keeping 2 copies of opt = xchg(&inet6_sk(sk)->opt, opt); then ? > Thanks for you remind, i didn't notice that. The else statement could be removed, opt = xchg(&inet6_sk(sk)->opt, opt); should be moved out, and i will send v2. Thanks, Duan > > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index e1a9583..92ca907 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -112,9 +112,7 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk, } opt = xchg(&inet6_sk(sk)->opt, opt); } else { - spin_lock(&sk->sk_dst_lock); opt = xchg(&inet6_sk(sk)->opt, opt); - spin_unlock(&sk->sk_dst_lock); } sk_dst_reset(sk);
xchg is atomic, so there is no necessary to use spin_lock/spin_unlock to protect it. Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> --- net/ipv6/ipv6_sockglue.c | 2 -- 1 file changed, 2 deletions(-)