On Wed, Sep 09, 2020 at 02:15:55PM -0400, Neal Cardwell wrote:
> Now that the previous patches ensure that all call sites for
> tcp_set_congestion_control() want to initialize congestion control, we
> can simplify tcp_set_congestion_control() by removing the reinit
> argument and the code to support it.
>
> Signed-off-by: Neal Cardwell <ncardw...@google.com>
> Acked-by: Yuchung Cheng <ych...@google.com>
> Acked-by: Kevin Yang <y...@google.com>
> Signed-off-by: Eric Dumazet <eduma...@google.com>
> Cc: Lawrence Brakmo <bra...@fb.com>
> ---
> include/net/tcp.h | 2 +-
> net/core/filter.c | 3 +--
> net/ipv4/tcp.c | 2 +-
> net/ipv4/tcp_cong.c | 11 ++---------
> 4 files changed, 5 insertions(+), 13 deletions(-)
>
> diff --git a/include/net/tcp.h b/include/net/tcp.h
> index e85d564446c6..f857146c17a5 100644
> --- a/include/net/tcp.h
> +++ b/include/net/tcp.h
> @@ -1104,7 +1104,7 @@ void tcp_get_available_congestion_control(char *buf,
> size_t len);
> void tcp_get_allowed_congestion_control(char *buf, size_t len);
> int tcp_set_allowed_congestion_control(char *allowed);
> int tcp_set_congestion_control(struct sock *sk, const char *name, bool load,
> - bool reinit, bool cap_net_admin);
> + bool cap_net_admin);
> u32 tcp_slow_start(struct tcp_sock *tp, u32 acked);
> void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w, u32 acked);
>
> diff --git a/net/core/filter.c b/net/core/filter.c
> index b26c04924fa3..0bd0a97ee951 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -4451,8 +4451,7 @@ static int _bpf_setsockopt(struct sock *sk, int level,
> int optname,
> strncpy(name, optval, min_t(long, optlen,
> TCP_CA_NAME_MAX-1));
> name[TCP_CA_NAME_MAX-1] = 0;
> - ret = tcp_set_congestion_control(sk, name, false,
> - true, true);
> + ret = tcp_set_congestion_control(sk, name, false, true);
> } else {
> struct inet_connection_sock *icsk = inet_csk(sk);
> struct tcp_sock *tp = tcp_sk(sk);
> diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
> index 7360d3db2b61..e58ab9db73ff 100644
> --- a/net/ipv4/tcp.c
> +++ b/net/ipv4/tcp.c
> @@ -3050,7 +3050,7 @@ static int do_tcp_setsockopt(struct sock *sk, int
> level, int optname,
> name[val] = 0;
>
> lock_sock(sk);
> - err = tcp_set_congestion_control(sk, name, true, true,
> + err = tcp_set_congestion_control(sk, name, true,
>
> ns_capable(sock_net(sk)->user_ns,
> CAP_NET_ADMIN));
> release_sock(sk);
> diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
> index d18d7a1ce4ce..a9b0fb52a1ec 100644
> --- a/net/ipv4/tcp_cong.c
> +++ b/net/ipv4/tcp_cong.c
> @@ -341,7 +341,7 @@ int tcp_set_allowed_congestion_control(char *val)
> * already initialized.
> */
> int tcp_set_congestion_control(struct sock *sk, const char *name, bool load,
> - bool reinit, bool cap_net_admin)
> + bool cap_net_admin)
> {
> struct inet_connection_sock *icsk = inet_csk(sk);
> const struct tcp_congestion_ops *ca;
> @@ -365,15 +365,8 @@ int tcp_set_congestion_control(struct sock *sk, const
> char *name, bool load,
> if (!ca) {
> err = -ENOENT;
> } else if (!load) {
nit.
I think this "else if (!load)" case can be completely removed and simply
allow it to fall through to the last
"else { tcp_reinit_congestion_control(sk, ca); }" .
> - const struct tcp_congestion_ops *old_ca = icsk->icsk_ca_ops;
> -
> if (bpf_try_module_get(ca, ca->owner)) {
> - if (reinit) {
> - tcp_reinit_congestion_control(sk, ca);
> - } else {
> - icsk->icsk_ca_ops = ca;
> - bpf_module_put(old_ca, old_ca->owner);
> - }
> + tcp_reinit_congestion_control(sk, ca);
> } else {
> err = -EBUSY;
> }
> --
> 2.28.0.526.ge36021eeef-goog
>
