@@ -12,6 +12,10 @@
SEC("struct_ops/"#name) \
BPF_PROG(name, args)
+#ifndef SOL_TCP
+#define SOL_TCP 6
+#endif
+
#define tcp_jiffies32 ((__u32)bpf_jiffies64())
struct sock_common {
@@ -4,37 +4,18 @@
#include <linux/err.h>
#include <netinet/tcp.h>
#include <test_progs.h>
+#include "network_helpers.h"
#include "bpf_dctcp.skel.h"
#include "bpf_cubic.skel.h"
#include "bpf_tcp_nogpl.skel.h"
+#include "bpf_dctcp_release.skel.h"
#define min(a, b) ((a) < (b) ? (a) : (b))
static const unsigned int total_bytes = 10 * 1024 * 1024;
-static const struct timeval timeo_sec = { .tv_sec = 10 };
-static const size_t timeo_optlen = sizeof(timeo_sec);
static int expected_stg = 0xeB9F;
static int stop, duration;
-static int settimeo(int fd)
-{
- int err;
-
- err = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec,
- timeo_optlen);
- if (CHECK(err == -1, "setsockopt(fd, SO_RCVTIMEO)", "errno:%d\n",
- errno))
- return -1;
-
- err = setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeo_sec,
- timeo_optlen);
- if (CHECK(err == -1, "setsockopt(fd, SO_SNDTIMEO)", "errno:%d\n",
- errno))
- return -1;
-
- return 0;
-}
-
static int settcpca(int fd, const char *tcp_ca)
{
int err;
@@ -61,7 +42,7 @@ static void *server(void *arg)
goto done;
}
- if (settimeo(fd)) {
+ if (settimeo(fd, 0)) {
err = -errno;
goto done;
}
@@ -114,7 +95,7 @@ static void do_test(const char *tcp_ca, const struct bpf_map *sk_stg_map)
}
if (settcpca(lfd, tcp_ca) || settcpca(fd, tcp_ca) ||
- settimeo(lfd) || settimeo(fd))
+ settimeo(lfd, 0) || settimeo(fd, 0))
goto done;
/* bind, listen and start server thread to accept */
@@ -267,6 +248,76 @@ static void test_invalid_license(void)
libbpf_set_print(old_print_fn);
}
+static void test_dctcp_fallback(void)
+{
+ int err, lfd = -1, cli_fd = -1, srv_fd = -1;
+ struct network_helper_opts opts = {
+ .cc = "cubic",
+ };
+ struct bpf_dctcp *dctcp_skel;
+ struct bpf_link *link = NULL;
+ char srv_cc[16];
+ socklen_t cc_len = sizeof(srv_cc);
+
+ dctcp_skel = bpf_dctcp__open();
+ if (!ASSERT_OK_PTR(dctcp_skel, "dctcp_skel"))
+ return;
+ strcpy(dctcp_skel->rodata->fallback, "cubic");
+ if (!ASSERT_OK(bpf_dctcp__load(dctcp_skel), "bpf_dctcp__load"))
+ goto done;
+
+ link = bpf_map__attach_struct_ops(dctcp_skel->maps.dctcp);
+ if (!ASSERT_OK_PTR(link, "dctcp link"))
+ goto done;
+
+ lfd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
+ if (!ASSERT_GE(lfd, 0, "lfd") ||
+ !ASSERT_OK(settcpca(lfd, "bpf_dctcp"), "lfd=>bpf_dctcp"))
+ goto done;
+
+ cli_fd = connect_to_fd_opts(lfd, &opts);
+ if (!ASSERT_GE(cli_fd, 0, "cli_fd"))
+ goto done;
+
+ srv_fd = accept(lfd, NULL, 0);
+ if (!ASSERT_GE(srv_fd, 0, "srv_fd"))
+ goto done;
+ ASSERT_STREQ(dctcp_skel->bss->cc_res, "cubic", "cc_res");
+
+ err = getsockopt(srv_fd, SOL_TCP, TCP_CONGESTION, srv_cc, &cc_len);
+ if (!ASSERT_OK(err, "getsockopt(srv_fd, TCP_CONGESTION)"))
+ goto done;
+ ASSERT_STREQ(srv_cc, "cubic", "srv_fd cc");
+
+done:
+ bpf_link__destroy(link);
+ bpf_dctcp__destroy(dctcp_skel);
+ if (lfd != -1)
+ close(lfd);
+ if (srv_fd != -1)
+ close(srv_fd);
+ if (cli_fd != -1)
+ close(cli_fd);
+}
+
+static void test_rel_setsockopt(void)
+{
+ struct bpf_dctcp_release *rel_skel;
+ libbpf_print_fn_t old_print_fn;
+
+ err_str = "unknown func bpf_setsockopt";
+ found = false;
+
+ old_print_fn = libbpf_set_print(libbpf_debug_print);
+ rel_skel = bpf_dctcp_release__open_and_load();
+ libbpf_set_print(old_print_fn);
+
+ ASSERT_ERR_PTR(rel_skel, "rel_skel");
+ ASSERT_TRUE(found, "expected_err_msg");
+
+ bpf_dctcp_release__destroy(rel_skel);
+}
+
void test_bpf_tcp_ca(void)
{
if (test__start_subtest("dctcp"))
@@ -275,4 +326,8 @@ void test_bpf_tcp_ca(void)
test_cubic();
if (test__start_subtest("invalid_license"))
test_invalid_license();
+ if (test__start_subtest("dctcp_fallback"))
+ test_dctcp_fallback();
+ if (test__start_subtest("rel_setsockopt"))
+ test_rel_setsockopt();
}
@@ -17,6 +17,9 @@
char _license[] SEC("license") = "GPL";
+volatile const char fallback[TCP_CA_NAME_MAX];
+const char bpf_dctcp[] = "bpf_dctcp";
+char cc_res[TCP_CA_NAME_MAX];
int stg_result = 0;
struct {
@@ -57,6 +60,23 @@ void BPF_PROG(dctcp_init, struct sock *sk)
struct dctcp *ca = inet_csk_ca(sk);
int *stg;
+ if (!(tp->ecn_flags & TCP_ECN_OK) && fallback[0]) {
+ /* Switch to fallback */
+ bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)fallback, sizeof(fallback));
+ /* Switch back to myself which the bpf trampoline
+ * stopped calling dctcp_init recursively.
+ */
+ bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)bpf_dctcp, sizeof(bpf_dctcp));
+ /* Switch back to fallback */
+ bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)fallback, sizeof(fallback));
+ bpf_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)cc_res, sizeof(cc_res));
+ return;
+ }
+
ca->prior_rcv_nxt = tp->rcv_nxt;
ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA);
ca->loss_cwnd = 0;
new file mode 100644
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include <stddef.h>
+#include <linux/bpf.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/tcp.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "bpf_tcp_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+const char cubic[] = "cubic";
+
+void BPF_STRUCT_OPS(dctcp_nouse_release, struct sock *sk)
+{
+ bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)cubic, sizeof(cubic));
+}
+
+SEC(".struct_ops")
+struct tcp_congestion_ops dctcp_rel = {
+ .release = (void *)dctcp_nouse_release,
+ .name = "bpf_dctcp_rel",
+};
This patch makes the bpf_dctcp test to fallback to cubic by using setsockopt(TCP_CONGESTION) when the tcp flow is not ecn ready. It also checks setsockopt() is not available to release(). The settimeo() from the network_helpers.h is used, so the local one is removed. Signed-off-by: Martin KaFai Lau <kafai@fb.com> --- tools/testing/selftests/bpf/bpf_tcp_helpers.h | 4 + .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 101 ++++++++++++++---- tools/testing/selftests/bpf/progs/bpf_dctcp.c | 20 ++++ .../selftests/bpf/progs/bpf_dctcp_release.c | 26 +++++ 4 files changed, 128 insertions(+), 23 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/bpf_dctcp_release.c