On Fri, Apr 26, 2019 at 10:55:02AM -0700, Stanislav Fomichev wrote:
> On 04/26, Martin KaFai Lau wrote:
> > This patch rides on an existing BPF_PROG_TYPE_CGROUP_SKB test
> > (test_sock_fields.c) to do a TCP end-to-end test on the new
> > bpf_sk_storage_* helpers.
> >
> > Signed-off-by: Martin KaFai Lau <[email protected]>
> > ---
> > tools/testing/selftests/bpf/bpf_helpers.h | 5 +
> > .../bpf/progs/test_sock_fields_kern.c | 49 ++++++++
> > .../testing/selftests/bpf/test_sock_fields.c | 115 +++++++++++++++---
> > 3 files changed, 153 insertions(+), 16 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_helpers.h
> > b/tools/testing/selftests/bpf/bpf_helpers.h
> > index 59e221586cf7..6e80b66d7fb1 100644
> > --- a/tools/testing/selftests/bpf/bpf_helpers.h
> > +++ b/tools/testing/selftests/bpf/bpf_helpers.h
> > @@ -211,6 +211,11 @@ static int (*bpf_strtol)(const char *buf, unsigned
> > long long buf_len,
> > static int (*bpf_strtoul)(const char *buf, unsigned long long buf_len,
> > unsigned long long flags, unsigned long *res) =
> > (void *) BPF_FUNC_strtoul;
> > +static void *(*bpf_sk_storage_get)(void *map, struct bpf_sock *sk,
> > + void *value, __u64 flags) =
> > + (void *) BPF_FUNC_sk_storage_get;
> > +static int (*bpf_sk_storage_delete)(void *map, struct bpf_sock *sk) =
> > + (void *)BPF_FUNC_sk_storage_delete;
> >
> > /* llvm builtin functions that eBPF C program may use to
> > * emit BPF_LD_ABS and BPF_LD_IND instructions
> > diff --git a/tools/testing/selftests/bpf/progs/test_sock_fields_kern.c
> > b/tools/testing/selftests/bpf/progs/test_sock_fields_kern.c
> > index 37328f148538..93ef3e039da3 100644
> > --- a/tools/testing/selftests/bpf/progs/test_sock_fields_kern.c
> > +++ b/tools/testing/selftests/bpf/progs/test_sock_fields_kern.c
> > @@ -55,6 +55,31 @@ struct bpf_map_def SEC("maps") linum_map = {
> > .max_entries = __NR_BPF_LINUM_ARRAY_IDX,
> > };
> >
> > +struct bpf_spinlock_cnt {
> > + struct bpf_spin_lock lock;
> > + __u32 cnt;
> > +};
> > +
> > +struct bpf_map_def SEC("maps") sk_pkt_out_cnt = {
> > + .type = BPF_MAP_TYPE_SK_STORAGE,
> > + .key_size = sizeof(int),
> > + .value_size = sizeof(struct bpf_spinlock_cnt),
> > + .max_entries = 0,
> > + .map_flags = BPF_F_NO_PREALLOC,
> > +};
> > +
> > +BPF_ANNOTATE_KV_PAIR(sk_pkt_out_cnt, int, struct bpf_spinlock_cnt);
> > +
> > +struct bpf_map_def SEC("maps") sk_pkt_out_cnt10 = {
> > + .type = BPF_MAP_TYPE_SK_STORAGE,
> > + .key_size = sizeof(int),
> > + .value_size = sizeof(struct bpf_spinlock_cnt),
> > + .max_entries = 0,
> > + .map_flags = BPF_F_NO_PREALLOC,
> > +};
> > +
> > +BPF_ANNOTATE_KV_PAIR(sk_pkt_out_cnt10, int, struct bpf_spinlock_cnt);
> > +
> > static bool is_loopback6(__u32 *a6)
> > {
> > return !a6[0] && !a6[1] && !a6[2] && a6[3] == bpf_htonl(1);
> > @@ -120,7 +145,9 @@ static void tpcpy(struct bpf_tcp_sock *dst,
> > SEC("cgroup_skb/egress")
> > int egress_read_sock_fields(struct __sk_buff *skb)
> > {
> > + struct bpf_spinlock_cnt cli_cnt_init = { .lock = 0, .cnt = 0xeB9F };
> > __u32 srv_idx = ADDR_SRV_IDX, cli_idx = ADDR_CLI_IDX, result_idx;
> > + struct bpf_spinlock_cnt *pkt_out_cnt, *pkt_out_cnt10;
> > struct sockaddr_in6 *srv_sa6, *cli_sa6;
> > struct bpf_tcp_sock *tp, *tp_ret;
> > struct bpf_sock *sk, *sk_ret;
> > @@ -161,6 +188,28 @@ int egress_read_sock_fields(struct __sk_buff *skb)
> > skcpy(sk_ret, sk);
> > tpcpy(tp_ret, tp);
> >
> > + if (result_idx == EGRESS_SRV_IDX) {
> > + /* The userspace has created it for srv sk */
> > + pkt_out_cnt = bpf_sk_storage_get(&sk_pkt_out_cnt, sk, 0, 0);
> > + pkt_out_cnt10 = bpf_sk_storage_get(&sk_pkt_out_cnt10, sk,
> > + 0, 0);
> > + } else {
> > + pkt_out_cnt = bpf_sk_storage_get(&sk_pkt_out_cnt, sk,
> > + &cli_cnt_init,
> > + BPF_SK_STORAGE_GET_F_CREATE);
> > + pkt_out_cnt10 = bpf_sk_storage_get(&sk_pkt_out_cnt10,
> > + sk, &cli_cnt_init,
> > + BPF_SK_STORAGE_GET_F_CREATE);
> > + }
> > +
> > + if (!pkt_out_cnt || !pkt_out_cnt10)
> > + RETURN;
> > +
> [..]
> > + pkt_out_cnt->cnt += 1;
> > + bpf_spin_lock(&pkt_out_cnt10->lock);
> > + pkt_out_cnt10->cnt += 10;
> > + bpf_spin_unlock(&pkt_out_cnt10->lock);
> Any reason only cnt10 is spin-locked? I see both of them use
> bpf_spinlock_cnt struct.
Intentionally one takes lock and one does not as a test.
I will add one comment here.
>
> > +
> > RETURN;
> > }
> >
> > diff --git a/tools/testing/selftests/bpf/test_sock_fields.c
> > b/tools/testing/selftests/bpf/test_sock_fields.c
> > index dcae7f664dce..550baf8aa1ca 100644
> > --- a/tools/testing/selftests/bpf/test_sock_fields.c
> > +++ b/tools/testing/selftests/bpf/test_sock_fields.c
> > @@ -35,6 +35,11 @@ enum bpf_linum_array_idx {
> > __NR_BPF_LINUM_ARRAY_IDX,
> > };
> >
> > +struct bpf_spinlock_cnt {
> > + struct bpf_spin_lock lock;
> > + __u32 cnt;
> > +};
> > +
> > #define CHECK(condition, tag, format...) ({
> > \
> > int __ret = !!(condition); \
> > if (__ret) { \
> > @@ -50,6 +55,8 @@ enum bpf_linum_array_idx {
> > #define DATA_LEN sizeof(DATA)
> >
> > static struct sockaddr_in6 srv_sa6, cli_sa6;
> > +static int sk_pkt_out_cnt10_fd;
> > +static int sk_pkt_out_cnt_fd;
> > static int linum_map_fd;
> > static int addr_map_fd;
> > static int tp_map_fd;
> > @@ -220,28 +227,90 @@ static void check_result(void)
> > "Unexpected listen_tp", "Check listen_tp output.
> > ingress_linum:%u",
> > ingress_linum);
> >
> > - CHECK(srv_tp.data_segs_out != 1 ||
> > + CHECK(srv_tp.data_segs_out != 2 ||
> > srv_tp.data_segs_in ||
> > srv_tp.snd_cwnd != 10 ||
> > srv_tp.total_retrans ||
> > - srv_tp.bytes_acked != DATA_LEN,
> > + srv_tp.bytes_acked != 2 * DATA_LEN,
> > "Unexpected srv_tp", "Check srv_tp output. egress_linum:%u",
> > egress_linum);
> >
> > CHECK(cli_tp.data_segs_out ||
> > - cli_tp.data_segs_in != 1 ||
> > + cli_tp.data_segs_in != 2 ||
> > cli_tp.snd_cwnd != 10 ||
> > cli_tp.total_retrans ||
> > - cli_tp.bytes_received != DATA_LEN,
> > + cli_tp.bytes_received != 2 * DATA_LEN,
> > "Unexpected cli_tp", "Check cli_tp output. egress_linum:%u",
> > egress_linum);
> > }
> >
> > +static void check_sk_pkt_out_cnt(int accept_fd, int cli_fd)
> > +{
> > + struct bpf_spinlock_cnt pkt_out_cnt = {} , pkt_out_cnt10 = {};
> > + int err;
> > +
> > + pkt_out_cnt.cnt = ~0;
> > + pkt_out_cnt10.cnt = ~0;
> > + err = bpf_map_lookup_elem(sk_pkt_out_cnt_fd, &accept_fd, &pkt_out_cnt);
> > + if (!err)
> > + err = bpf_map_lookup_elem(sk_pkt_out_cnt10_fd, &accept_fd,
> > + &pkt_out_cnt10);
> > +
> > + /* The bpf prog only counts for fullsock and
> > + * passive conneciton did not become fullsock until 3WHS
> > + * had been finished.
> > + * The bpf prog only counted two data packet out but we
> > + * specially init accept_fd's pkt_out_cnt by 2 in
> > + * init_sk_storage(). Hence, 4 here.
> > + */
> > + CHECK(err || pkt_out_cnt.cnt != 4 || pkt_out_cnt10.cnt != 40,
> > + "bpf_map_lookup_elem(sk_pkt_out_cnt, &accept_fd)",
> > + "err:%d errno:%d pkt_out_cnt:%u pkt_out_cnt10:%u",
> > + err, errno, pkt_out_cnt.cnt, pkt_out_cnt10.cnt);
> > +
> > + pkt_out_cnt.cnt = ~0;
> > + pkt_out_cnt10.cnt = ~0;
> > + err = bpf_map_lookup_elem(sk_pkt_out_cnt_fd, &cli_fd, &pkt_out_cnt);
> > + if (!err)
> > + err = bpf_map_lookup_elem(sk_pkt_out_cnt10_fd, &cli_fd,
> > + &pkt_out_cnt10);
> > + /* Active connection is fullsock from the beginning.
> > + * 1 SYN and 1 ACK during 3WHS
> > + * 2 Acks on data packet.
> > + *
> > + * The bpf_prog initialized it to 0xeB9F.
> > + */
> > + CHECK(err || pkt_out_cnt.cnt != 0xeB9F + 4 ||
> > + pkt_out_cnt10.cnt != 0xeB9F + 40,
> > + "bpf_map_lookup_elem(sk_pkt_out_cnt, &cli_fd)",
> > + "err:%d errno:%d pkt_out_cnt:%u pkt_out_cnt10:%u",
> > + err, errno, pkt_out_cnt.cnt, pkt_out_cnt10.cnt);
> > +}
> > +
> > +static void init_sk_storage(int sk_fd, __u32 pkt_out_cnt)
> > +{
> > + struct bpf_spinlock_cnt scnt = {};
> > + int err;
> > +
> > + scnt.cnt = pkt_out_cnt;
> > + err = bpf_map_update_elem(sk_pkt_out_cnt_fd, &sk_fd, &scnt,
> > + BPF_NOEXIST);
> > + CHECK(err, "bpf_map_update_elem(sk_pkt_out_cnt_fd)",
> > + "err:%d errno:%d", err, errno);
> > +
> > + scnt.cnt *= 10;
> > + err = bpf_map_update_elem(sk_pkt_out_cnt10_fd, &sk_fd, &scnt,
> > + BPF_NOEXIST);
> > + CHECK(err, "bpf_map_update_elem(sk_pkt_out_cnt10_fd)",
> > + "err:%d errno:%d", err, errno);
> > +}
> > +
> > static void test(void)
> > {
> > int listen_fd, cli_fd, accept_fd, epfd, err;
> > struct epoll_event ev;
> > socklen_t addrlen;
> > + int i;
> >
> > addrlen = sizeof(struct sockaddr_in6);
> > ev.events = EPOLLIN;
> > @@ -308,24 +377,30 @@ static void test(void)
> > accept_fd, errno);
> > close(listen_fd);
> >
> > - /* Send some data from accept_fd to cli_fd */
> > - err = send(accept_fd, DATA, DATA_LEN, 0);
> > - CHECK(err != DATA_LEN, "send(accept_fd)", "err:%d errno:%d",
> > - err, errno);
> > -
> > - /* Have some timeout in recv(cli_fd). Just in case. */
> > ev.data.fd = cli_fd;
> > err = epoll_ctl(epfd, EPOLL_CTL_ADD, cli_fd, &ev);
> > CHECK(err, "epoll_ctl(EPOLL_CTL_ADD, cli_fd)", "err:%d errno:%d",
> > err, errno);
> >
> > - err = epoll_wait(epfd, &ev, 1, 1000);
> > - CHECK(err != 1 || ev.data.fd != cli_fd,
> > - "epoll_wait(cli_fd)", "err:%d errno:%d ev.data.fd:%d cli_fd:%d",
> > - err, errno, ev.data.fd, cli_fd);
> > + init_sk_storage(accept_fd, 2);
> >
> > - err = recv(cli_fd, NULL, 0, MSG_TRUNC);
> > - CHECK(err, "recv(cli_fd)", "err:%d errno:%d", err, errno);
> > + for (i = 0; i < 2; i++) {
> > + /* Send some data from accept_fd to cli_fd */
> > + err = send(accept_fd, DATA, DATA_LEN, 0);
> > + CHECK(err != DATA_LEN, "send(accept_fd)", "err:%d errno:%d",
> > + err, errno);
> > +
> > + /* Have some timeout in recv(cli_fd). Just in case. */
> > + err = epoll_wait(epfd, &ev, 1, 1000);
> > + CHECK(err != 1 || ev.data.fd != cli_fd,
> > + "epoll_wait(cli_fd)", "err:%d errno:%d ev.data.fd:%d
> > cli_fd:%d",
> > + err, errno, ev.data.fd, cli_fd);
> > +
> > + err = recv(cli_fd, NULL, 0, MSG_TRUNC);
> > + CHECK(err, "recv(cli_fd)", "err:%d errno:%d", err, errno);
> > + }
> > +
> > + check_sk_pkt_out_cnt(accept_fd, cli_fd);
> >
> > close(epfd);
> > close(accept_fd);
> > @@ -395,6 +470,14 @@ int main(int argc, char **argv)
> > CHECK(!map, "cannot find linum_map", "(null)");
> > linum_map_fd = bpf_map__fd(map);
> >
> > + map = bpf_object__find_map_by_name(obj, "sk_pkt_out_cnt");
> > + CHECK(!map, "cannot find sk_pkt_out_cnt", "(null)");
> > + sk_pkt_out_cnt_fd = bpf_map__fd(map);
> > +
> > + map = bpf_object__find_map_by_name(obj, "sk_pkt_out_cnt10");
> > + CHECK(!map, "cannot find sk_pkt_out_cnt10", "(null)");
> > + sk_pkt_out_cnt10_fd = bpf_map__fd(map);
> > +
> > test();
> >
> > bpf_object__close(obj);
> > --
> > 2.17.1
> >
