This patch adds similar retry logic to more places where read() is used, to
reduce flakyness in slow CI environment.

Signed-off-by: Yucong Sun <redacted>
---
 .../selftests/bpf/prog_tests/sockmap_listen.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c
index 6a5df28f9a3d..5c5979046523 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c

@@ -949,6 +949,7 @@ static void redir_to_connected(int family, int sotype, int sock_mapfd,
        int err, n;
        u32 key;
        char b;
+       int retries = 100;

        zero_verdict_count(verd_mapfd);

@@ -1001,10 +1002,15 @@ static void redir_to_connected(int family, int sotype, int sock_mapfd,
                goto close_peer1;
        if (pass != 1)
                FAIL("%s: want pass count 1, have %d", log_prefix, pass);
-
+again:
        n = read(c0, &b, 1);
-       if (n < 0)
+       if (n < 0) {
+               if (errno == EAGAIN && retries--) {