diff options
| author | Eric Dumazet <edumazet@google.com> | 2016-10-20 06:24:58 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-10-20 17:24:32 +0200 |
| commit | 9652dc2eb9e40d100e0a3abfdcc0ea852c8be254 (patch) | |
| tree | e3efd14c1b27eba8a65381fa769023fb9f473831 | |
| parent | net: smc91x: fix neponset breakage by pxa u16 writes (diff) | |
| download | linux-9652dc2eb9e40d100e0a3abfdcc0ea852c8be254.tar.xz linux-9652dc2eb9e40d100e0a3abfdcc0ea852c8be254.zip | |
tcp: relax listening_hash operations
softirq handlers use RCU protection to lookup listeners,
and write operations all happen from process context.
We do not need to block BH for dump operations.
Also SYN_RECV since request sockets are stored in the ehash table :
1) inet_diag_dump_icsk() no longer need to clear
cb->args[3] and cb->args[4] that were used as cursors while
iterating the old per listener hash table.
2) Also factorize a test : No need to scan listening_hash[]
if r->id.idiag_dport is not zero.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/inet_diag.c | 16 | ||||
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 6 |
2 files changed, 7 insertions, 15 deletions
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index e4d16fc5bbb3..0a1d4a896a26 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -863,7 +863,7 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb, s_num = num = cb->args[2]; if (cb->args[0] == 0) { - if (!(idiag_states & TCPF_LISTEN)) + if (!(idiag_states & TCPF_LISTEN) || r->id.idiag_dport) goto skip_listen_ht; for (i = s_i; i < INET_LHTABLE_SIZE; i++) { @@ -872,7 +872,7 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb, num = 0; ilb = &hashinfo->listening_hash[i]; - spin_lock_bh(&ilb->lock); + spin_lock(&ilb->lock); sk_for_each(sk, &ilb->head) { struct inet_sock *inet = inet_sk(sk); @@ -892,26 +892,18 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb, r->id.idiag_sport) goto next_listen; - if (r->id.idiag_dport || - cb->args[3] > 0) - goto next_listen; - if (inet_csk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) { - spin_unlock_bh(&ilb->lock); + spin_unlock(&ilb->lock); goto done; } next_listen: - cb->args[3] = 0; - cb->args[4] = 0; ++num; } - spin_unlock_bh(&ilb->lock); + spin_unlock(&ilb->lock); s_num = 0; - cb->args[3] = 0; - cb->args[4] = 0; } skip_listen_ht: cb->args[0] = 1; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index bd5e8d10893f..83b3d0b8c481 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1893,7 +1893,7 @@ static void *listening_get_next(struct seq_file *seq, void *cur) if (!sk) { get_head: ilb = &tcp_hashinfo.listening_hash[st->bucket]; - spin_lock_bh(&ilb->lock); + spin_lock(&ilb->lock); sk = sk_head(&ilb->head); st->offset = 0; goto get_sk; @@ -1911,7 +1911,7 @@ get_sk: return sk; icsk = inet_csk(sk); } - spin_unlock_bh(&ilb->lock); + spin_unlock(&ilb->lock); st->offset = 0; if (++st->bucket < INET_LHTABLE_SIZE) goto get_head; @@ -2119,7 +2119,7 @@ static void tcp_seq_stop(struct seq_file *seq, void *v) switch (st->state) { case TCP_SEQ_STATE_LISTENING: if (v != SEQ_START_TOKEN) - spin_unlock_bh(&tcp_hashinfo.listening_hash[st->bucket].lock); + spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock); break; case TCP_SEQ_STATE_ESTABLISHED: if (v) |