diff options
| author | Ingo Molnar <mingo@kernel.org> | 2016-12-11 13:07:13 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-12-11 13:07:13 +0100 |
| commit | 6f38751510073cc054c5dffc3339b22f9385ceed (patch) | |
| tree | b7704b2d3388293118a6794f7a858e8891bcec60 /net/ipv4/tcp_input.c | |
| parent | f4ec57b632fe15ed7a355099cb96ed4b647416de (diff) | |
| parent | 045169816b31b10faed984b01c390db1b32ee4c1 (diff) | |
Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a27b9c0e27c0..c71d49ce0c93 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -128,6 +128,23 @@ int sysctl_tcp_invalid_ratelimit __read_mostly = HZ/2; #define REXMIT_LOST 1 /* retransmit packets marked lost */ #define REXMIT_NEW 2 /* FRTO-style transmit of unsent/new packets */ +static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb) +{ + static bool __once __read_mostly; + + if (!__once) { + struct net_device *dev; + + __once = true; + + rcu_read_lock(); + dev = dev_get_by_index_rcu(sock_net(sk), skb->skb_iif); + pr_warn("%s: Driver has suspect GRO implementation, TCP performance may be compromised.\n", + dev ? dev->name : "Unknown driver"); + rcu_read_unlock(); + } +} + /* Adapt the MSS value used to make delayed ack decision to the * real world. */ @@ -144,7 +161,10 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb) */ len = skb_shinfo(skb)->gso_size ? : skb->len; if (len >= icsk->icsk_ack.rcv_mss) { - icsk->icsk_ack.rcv_mss = len; + icsk->icsk_ack.rcv_mss = min_t(unsigned int, len, + tcp_sk(sk)->advmss); + if (unlikely(icsk->icsk_ack.rcv_mss != len)) + tcp_gro_dev_warn(sk, skb); } else { /* Otherwise, we make more careful check taking into account, * that SACKs block is variable. |