[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAPhsuW7ZEHf91co+xczJrkKAwKFMaoB=sCwuGUiOZ-x1Wk06Rw@mail.gmail.com>
Date: Mon, 28 Jan 2019 09:24:13 -0800
From: Song Liu <liu.song.a23@...il.com>
To: Stanislav Fomichev <sdf@...ichev.me>
Cc: Stanislav Fomichev <sdf@...gle.com>,
Networking <netdev@...r.kernel.org>,
"David S . Miller" <davem@...emloft.net>,
Alexei Starovoitov <ast@...nel.org>,
Daniel Borkmann <daniel@...earbox.net>
Subject: Re: [PATCH bpf-next v2 2/3] bpf: add BPF_PROG_TEST_RUN support for
flow dissector
On Fri, Jan 25, 2019 at 4:56 PM Stanislav Fomichev <sdf@...ichev.me> wrote:
>
> On 01/25, Song Liu wrote:
> > On Thu, Jan 24, 2019 at 8:53 AM Stanislav Fomichev <sdf@...gle.com> wrote:
> > >
> > > The input is packet data, the output is struct bpf_flow_key. This should
> > > make it easy to test flow dissector programs without elaborate
> > > setup.
> > >
> > > Signed-off-by: Stanislav Fomichev <sdf@...gle.com>
> > > ---
> > > include/linux/bpf.h | 3 ++
> > > net/bpf/test_run.c | 82 +++++++++++++++++++++++++++++++++++++++++++++
> > > net/core/filter.c | 1 +
> > > 3 files changed, 86 insertions(+)
> > >
> > > diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> > > index e734f163bd0b..701ef954a258 100644
> > > --- a/include/linux/bpf.h
> > > +++ b/include/linux/bpf.h
> > > @@ -397,6 +397,9 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
> > > union bpf_attr __user *uattr);
> > > int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
> > > union bpf_attr __user *uattr);
> > > +int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
> > > + const union bpf_attr *kattr,
> > > + union bpf_attr __user *uattr);
> > >
> > > /* an array of programs to be executed under rcu_lock.
> > > *
> > > diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
> > > index fa2644d276ef..2c5172b33209 100644
> > > --- a/net/bpf/test_run.c
> > > +++ b/net/bpf/test_run.c
> > > @@ -240,3 +240,85 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
> > > kfree(data);
> > > return ret;
> > > }
> > > +
> > > +int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
> > > + const union bpf_attr *kattr,
> > > + union bpf_attr __user *uattr)
> >
> > I think this function duplicates a lot of logic from bpf_prog_test_run_skb().
> > Can we somehow reuse bpf_prog_test_run_skb()?
> I did that initially
> (https://marc.info/?l=linux-netdev&m=154830227529929&w=2), but then
> Alexey suggested that there is not much to reuse (plus can hinder the
> test performance of the existing types).
I see.
Acked-by: Song Liu <songliubraving@...com>
Thanks!
> >
> > Thanks,
> > Song
> >
> >
> > > +{
> > > + u32 size = kattr->test.data_size_in;
> > > + u32 repeat = kattr->test.repeat;
> > > + struct bpf_flow_keys flow_keys;
> > > + u64 time_start, time_spent = 0;
> > > + struct bpf_skb_data_end *cb;
> > > + u32 retval, duration;
> > > + struct sk_buff *skb;
> > > + struct sock *sk;
> > > + void *data;
> > > + int ret;
> > > + u32 i;
> > > +
> > > + if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR)
> > > + return -EINVAL;
> > > +
> > > + data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
> > > + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
> > > + if (IS_ERR(data))
> > > + return PTR_ERR(data);
> > > +
> > > + sk = kzalloc(sizeof(*sk), GFP_USER);
> > > + if (!sk) {
> > > + kfree(data);
> > > + return -ENOMEM;
> > > + }
> > > + sock_net_set(sk, current->nsproxy->net_ns);
> > > + sock_init_data(NULL, sk);
> > > +
> > > + skb = build_skb(data, 0);
> > > + if (!skb) {
> > > + kfree(data);
> > > + kfree(sk);
> > > + return -ENOMEM;
> > > + }
> > > + skb->sk = sk;
> > > +
> > > + skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
> > > + __skb_put(skb, size);
> > > + skb->protocol = eth_type_trans(skb,
> > > + current->nsproxy->net_ns->loopback_dev);
> > > + skb_reset_network_header(skb);
> > > +
> > > + cb = (struct bpf_skb_data_end *)skb->cb;
> > > + cb->qdisc_cb.flow_keys = &flow_keys;
> > > +
> > > + if (!repeat)
> > > + repeat = 1;
> > > +
> > > + time_start = ktime_get_ns();
> > > + for (i = 0; i < repeat; i++) {
> > > + preempt_disable();
> > > + rcu_read_lock();
> > > + retval = __skb_flow_bpf_dissect(prog, skb,
> > > + &flow_keys_dissector,
> > > + &flow_keys);
> > > + rcu_read_unlock();
> > > + preempt_enable();
> > > +
> > > + if (need_resched()) {
> > > + if (signal_pending(current))
> > > + break;
> > > + time_spent += ktime_get_ns() - time_start;
> > > + cond_resched();
> > > + time_start = ktime_get_ns();
> > > + }
> > > + }
> > > + time_spent += ktime_get_ns() - time_start;
> > > + do_div(time_spent, repeat);
> > > + duration = time_spent > U32_MAX ? U32_MAX : (u32)time_spent;
> > > +
> > > + ret = bpf_test_finish(kattr, uattr, &flow_keys, sizeof(flow_keys),
> > > + retval, duration);
> > > +
> > > + kfree_skb(skb);
> > > + kfree(sk);
> > > + return ret;
> > > +}
> > > diff --git a/net/core/filter.c b/net/core/filter.c
> > > index 2b3b436ef545..ff4641dae2be 100644
> > > --- a/net/core/filter.c
> > > +++ b/net/core/filter.c
> > > @@ -7690,6 +7690,7 @@ const struct bpf_verifier_ops flow_dissector_verifier_ops = {
> > > };
> > >
> > > const struct bpf_prog_ops flow_dissector_prog_ops = {
> > > + .test_run = bpf_prog_test_run_flow_dissector,
> > > };
> > >
> > > int sk_detach_filter(struct sock *sk)
> > > --
> > > 2.20.1.321.g9e740568ce-goog
> > >
Powered by blists - more mailing lists