On Tue, May 02, 2023 at 08:51 AM -07, John Fastabend wrote:
> When session gracefully shutdowns epoll needs to wake up and any recv()
> readers should return 0 not the -EAGAIN they previously returned.
>
> Note we use epoll instead of select to test the epoll wake on shutdown
> event as well.
>
> Signed-off-by: John Fastabend <john.fastabend@xxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/sockmap_basic.c | 68 +++++++++++++++++++
> .../bpf/progs/test_sockmap_pass_prog.c | 32 +++++++++
> 2 files changed, 100 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_pass_prog.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
> index 0ce25a967481..f9f611618e45 100644
> --- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
> +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
> @@ -2,6 +2,7 @@
> // Copyright (c) 2020 Cloudflare
> #include <error.h>
> #include <netinet/tcp.h>
> +#include <sys/epoll.h>
>
> #include "test_progs.h"
> #include "test_skmsg_load_helpers.skel.h"
> @@ -9,8 +10,11 @@
> #include "test_sockmap_invalid_update.skel.h"
> #include "test_sockmap_skb_verdict_attach.skel.h"
> #include "test_sockmap_progs_query.skel.h"
> +#include "test_sockmap_pass_prog.skel.h"
> #include "bpf_iter_sockmap.skel.h"
>
> +#include "sockmap_helpers.h"
> +
> #define TCP_REPAIR 19 /* TCP sock is under repair right now */
>
> #define TCP_REPAIR_ON 1
> @@ -350,6 +354,68 @@ static void test_sockmap_progs_query(enum bpf_attach_type attach_type)
> test_sockmap_progs_query__destroy(skel);
> }
>
> +#define MAX_EVENTS 10
> +static void test_sockmap_skb_verdict_shutdown(void)
> +{
> + int n, err, map, verdict, s, c0, c1, p0, p1;
> + struct epoll_event ev, events[MAX_EVENTS];
> + struct test_sockmap_pass_prog *skel;
> + int epollfd;
> + int zero = 0;
> + char b;
> +
> + skel = test_sockmap_pass_prog__open_and_load();
> + if (!ASSERT_OK_PTR(skel, "open_and_load"))
> + return;
> +
> + verdict = bpf_program__fd(skel->progs.prog_skb_verdict);
> + map = bpf_map__fd(skel->maps.sock_map_rx);
> +
> + err = bpf_prog_attach(verdict, map, BPF_SK_SKB_STREAM_VERDICT, 0);
> + if (!ASSERT_OK(err, "bpf_prog_attach"))
> + goto out;
> +
> + s = socket_loopback(AF_INET, SOCK_STREAM);
> + if (s < 0)
> + goto out;
> + err = create_socket_pairs(s, AF_INET, SOCK_STREAM, &c0, &c1, &p0, &p1);
> + if (err < 0)
> + goto out;
> +
> + err = bpf_map_update_elem(map, &zero, &c1, BPF_NOEXIST);
> + if (err < 0)
> + goto out_close;
> +
> + shutdown(c0, SHUT_RDWR);
> + shutdown(p1, SHUT_WR);
> +
> + ev.events = EPOLLIN;
> + ev.data.fd = c1;
> +
> + epollfd = epoll_create1(0);
> + if (!ASSERT_GT(epollfd, -1, "epoll_create(0)"))
> + goto out_close;
> + err = epoll_ctl(epollfd, EPOLL_CTL_ADD, c1, &ev);
> + if (!ASSERT_OK(err, "epoll_ctl(EPOLL_CTL_ADD)"))
> + goto out_close;
> + err = epoll_wait(epollfd, events, MAX_EVENTS, -1);
> + if (!ASSERT_EQ(err, 1, "epoll_wait(fd)"))
> + goto out_close;
> +
> + n = recv(c1, &b, 1, SOCK_NONBLOCK);
> + ASSERT_EQ(n, 0, "recv_timeout(fin)");
> + n = recv(p0, &b, 1, SOCK_NONBLOCK);
> + ASSERT_EQ(n, 0, "recv_timeout(fin)");
> +
> +out_close:
> + close(c0);
> + close(p0);
> + close(c1);
> + close(p1);
> +out:
> + test_sockmap_pass_prog__destroy(skel);
> +}
> +
This test has me scratching my head. I don't grasp what we're testing
with (c0, p0) socket pair, since c0 is not in any sockmap?
