selftests/bpf: Add tracing tests for walking skb and req.

Add tracing tests for walking skb->sk and req->sk.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-9-alexei.starovoitov@gmail.com

dccp/tcp: Remove an unused argument in inet_csk_listen_start().

The commit 1295e2cf3065 ("inet: minor optimization for backlog setting in
listen(2)") added change so that sk_max_ack_backlog is initialised earlier
in inet_dccp_listen() and inet_listen(). Since then, we no longer use
backlog in inet_csk_listen_start(), so let's remove it.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Richard Sailer <richard_siegfried@systemli.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP

This patch tests storing the task's related info into the
bpf_sk_storage by fentry/fexit tracing at listen, accept,
and connect. It also tests the raw_tp at inet_sock_set_state.

A negative test is done by tracing the bpf_sk_storage_free()
and using bpf_sk_storage_get() at the same time. It ensures
this bpf program cannot load.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201112211320.2587537-1-kafai@fb.com