aboutsummaryrefslogtreecommitdiffstats
path: root/net
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2015-06-11 09:15:16 -0700
committerDavid S. Miller <davem@davemloft.net>2015-06-11 16:33:11 -0700
commit51466a7545b73b7ad7bcfb33410d2823ccfaa501 (patch)
treef12fe132349a599b567efc45a092bbf2f591ea3d /net
parenta7eea416cb08a514f94c0ca5ff30c18783fab054 (diff)
tcp: fill shinfo->gso_type at last moment
Our goal is to touch skb_shinfo(skb) only when absolutely needed, to avoid two cache line misses in TCP output path for last skb that is considered but not sent because of various conditions (cwnd, tso defer, receiver window, TSQ...) A packet is GSO only when skb_shinfo(skb)->gso_size is not zero. We can set skb_shinfo(skb)->gso_type to sk->sk_gso_type even for non GSO packets. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/tcp_input.c8
-rw-r--r--net/ipv4/tcp_output.c4
2 files changed, 3 insertions, 9 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index d4f76ab6e136..70a6fa8ecbd3 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1316,16 +1316,12 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
* code can come after this skb later on it's better to keep
* setting gso_size to something.
*/
- if (!skb_shinfo(prev)->gso_size) {
+ if (!skb_shinfo(prev)->gso_size)
skb_shinfo(prev)->gso_size = mss;
- skb_shinfo(prev)->gso_type = sk->sk_gso_type;
- }
/* CHECKME: To clear or not to clear? Mimics normal skb currently */
- if (tcp_skb_pcount(skb) <= 1) {
+ if (tcp_skb_pcount(skb) <= 1)
skb_shinfo(skb)->gso_size = 0;
- skb_shinfo(skb)->gso_type = 0;
- }
/* Difference in this won't matter, both ACKed by the same cumul. ACK */
TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index eeb59befaf06..a51f7aab27d6 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -412,7 +412,6 @@ static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags)
tcp_skb_pcount_set(skb, 1);
shinfo->gso_size = 0;
- shinfo->gso_type = 0;
TCP_SKB_CB(skb)->seq = seq;
if (flags & (TCPHDR_SYN | TCPHDR_FIN))
@@ -1003,6 +1002,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
}
tcp_options_write((__be32 *)(th + 1), tp, &opts);
+ skb_shinfo(skb)->gso_type = sk->sk_gso_type;
if (likely((tcb->tcp_flags & TCPHDR_SYN) == 0))
tcp_ecn_send(sk, skb, tcp_header_size);
@@ -1080,11 +1080,9 @@ static void tcp_set_skb_tso_segs(const struct sock *sk, struct sk_buff *skb,
*/
tcp_skb_pcount_set(skb, 1);
shinfo->gso_size = 0;
- shinfo->gso_type = 0;
} else {
tcp_skb_pcount_set(skb, DIV_ROUND_UP(skb->len, mss_now));
shinfo->gso_size = mss_now;
- shinfo->gso_type = sk->sk_gso_type;
}
}

Privacy Policy