| Message ID | 20240408125753.470419-5-amorenoz@redhat.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: openvswitch: Add sample multicasting. | expand |
[copying my previous reply since this version actually has netdev@ in Cc] On 4/8/24 14:57, Adrian Moreno wrote: > If the action has a user_cookie, pass it along to the sample so it can > be easily identified. > > Signed-off-by: Adrian Moreno <amorenoz@redhat.com> > --- > net/sched/act_sample.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) Nit: some spaces in the subject would be nice. > > diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c > index a69b53d54039..5c3f86ec964a 100644 > --- a/net/sched/act_sample.c > +++ b/net/sched/act_sample.c > @@ -165,9 +165,11 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, > const struct tc_action *a, > struct tcf_result *res) > { > + u8 cookie_data[TC_COOKIE_MAX_SIZE] = {}; > struct tcf_sample *s = to_sample(a); > struct psample_group *psample_group; > struct psample_metadata md = {}; > + struct tc_cookie *user_cookie; > int retval; > > tcf_lastuse_update(&s->tcf_tm); > @@ -189,6 +191,16 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, > if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) > skb_push(skb, skb->mac_len); > > + rcu_read_lock(); > + user_cookie = rcu_dereference(a->user_cookie); > + if (user_cookie) { > + memcpy(cookie_data, user_cookie->data, > + user_cookie->len); > + md.user_cookie = cookie_data; > + md.user_cookie_len = user_cookie->len; > + } > + rcu_read_unlock(); Not sure what is better - extending rcu critical section beyond psample_sample_packet() or copying the cookie... What do you think? > + > md.trunc_size = s->truncate ? s->trunc_size : skb->len; > psample_sample_packet(psample_group, skb, s->rate, &md); >
On 4/8/24 15:20, Ilya Maximets wrote: > [copying my previous reply since this version actually has netdev@ in Cc] > > On 4/8/24 14:57, Adrian Moreno wrote: >> If the action has a user_cookie, pass it along to the sample so it can >> be easily identified. >> >> Signed-off-by: Adrian Moreno <amorenoz@redhat.com> >> --- >> net/sched/act_sample.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) > > Nit: some spaces in the subject would be nice. > >> >> diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c >> index a69b53d54039..5c3f86ec964a 100644 >> --- a/net/sched/act_sample.c >> +++ b/net/sched/act_sample.c >> @@ -165,9 +165,11 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, >> const struct tc_action *a, >> struct tcf_result *res) >> { >> + u8 cookie_data[TC_COOKIE_MAX_SIZE] = {}; >> struct tcf_sample *s = to_sample(a); >> struct psample_group *psample_group; >> struct psample_metadata md = {}; >> + struct tc_cookie *user_cookie; >> int retval; >> >> tcf_lastuse_update(&s->tcf_tm); >> @@ -189,6 +191,16 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, >> if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) >> skb_push(skb, skb->mac_len); >> >> + rcu_read_lock(); >> + user_cookie = rcu_dereference(a->user_cookie); >> + if (user_cookie) { >> + memcpy(cookie_data, user_cookie->data, >> + user_cookie->len); >> + md.user_cookie = cookie_data; >> + md.user_cookie_len = user_cookie->len; >> + } >> + rcu_read_unlock(); > > Not sure what is better - extending rcu critical section > beyond psample_sample_packet() or copying the cookie... > What do you think? Ha! I also scratched my head on this one. I tried to follow all the possible paths and, as far as I could tell, there is no explicit sleeping involved. However, there is a call to yield() towards the end of netlink_broadcast_filtered() that made me think it's safer to copy the cookie which, in this particular case, is fairly limited in size. Have I missed something? > >> + >> md.trunc_size = s->truncate ? s->trunc_size : skb->len; >> psample_sample_packet(psample_group, skb, s->rate, &md); >> >
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c index a69b53d54039..5c3f86ec964a 100644 --- a/net/sched/act_sample.c +++ b/net/sched/act_sample.c @@ -165,9 +165,11 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, const struct tc_action *a, struct tcf_result *res) { + u8 cookie_data[TC_COOKIE_MAX_SIZE] = {}; struct tcf_sample *s = to_sample(a); struct psample_group *psample_group; struct psample_metadata md = {}; + struct tc_cookie *user_cookie; int retval; tcf_lastuse_update(&s->tcf_tm); @@ -189,6 +191,16 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) skb_push(skb, skb->mac_len); + rcu_read_lock(); + user_cookie = rcu_dereference(a->user_cookie); + if (user_cookie) { + memcpy(cookie_data, user_cookie->data, + user_cookie->len); + md.user_cookie = cookie_data; + md.user_cookie_len = user_cookie->len; + } + rcu_read_unlock(); + md.trunc_size = s->truncate ? s->trunc_size : skb->len; psample_sample_packet(psample_group, skb, s->rate, &md);
If the action has a user_cookie, pass it along to the sample so it can be easily identified. Signed-off-by: Adrian Moreno <amorenoz@redhat.com> --- net/sched/act_sample.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)