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tcp: set TCP_KEEPCNT locklessly

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tp->keepalive_probes can be set locklessly, readers
are already taking care of this field being potentially
set by other threads.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2023-08-04 14:46:14 +00:00 committed by David S. Miller
parent 6fd70a6b4e
commit 84485080cb
1 changed files with 2 additions and 8 deletions
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10
net/ipv4/tcp.c
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@ -3358,10 +3358,8 @@ int tcp_sock_set_keepcnt(struct sock *sk, int val)
if (val < 1 || val > MAX_TCP_KEEPCNT)
return -EINVAL;
lock_sock(sk);
/* Paired with READ_ONCE() in keepalive_probes() */
WRITE_ONCE(tcp_sk(sk)->keepalive_probes, val);
release_sock(sk);
return 0;
}
EXPORT_SYMBOL(tcp_sock_set_keepcnt);
@ -3471,6 +3469,8 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
return tcp_sock_set_user_timeout(sk, val);
case TCP_KEEPINTVL:
return tcp_sock_set_keepintvl(sk, val);
case TCP_KEEPCNT:
return tcp_sock_set_keepcnt(sk, val);
}
sockopt_lock_sock(sk);
@ -3568,12 +3568,6 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
case TCP_KEEPIDLE:
err = tcp_sock_set_keepidle_locked(sk, val);
break;
case TCP_KEEPCNT:
if (val < 1 || val > MAX_TCP_KEEPCNT)
err = -EINVAL;
else
WRITE_ONCE(tp->keepalive_probes, val);
break;
case TCP_SAVE_SYN:
/* 0: disable, 1: enable, 2: start from ether_header */
if (val < 0 || val > 2)