summaryrefslogtreecommitdiffstats
path: root/net/ipv4/tcp_output.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@kernel.org>2013-10-15 07:05:06 +0200
committerIngo Molnar <mingo@kernel.org>2013-10-15 07:05:18 +0200
commit426ee9e3bbc478ed9c0a079a4270f6095f0eb975 (patch)
treed8f295e2e516a61b2ab8ccb49f5b1d9fb67979bd /net/ipv4/tcp_output.c
parentb7af41a1bc255c0098c37a4bcf5c7e5e168ce875 (diff)
parent61e6cfa80de5760bbe406f4e815b7739205754d2 (diff)
Merge tag 'v3.12-rc5' into perf/core
Merge Linux v3.12-rc5, to pick up the latest fixes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c17
1 files changed, 11 insertions, 6 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 7c83cb8bf13..e6bb8256e59 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -895,8 +895,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
skb_orphan(skb);
skb->sk = sk;
- skb->destructor = (sysctl_tcp_limit_output_bytes > 0) ?
- tcp_wfree : sock_wfree;
+ skb->destructor = tcp_wfree;
atomic_add(skb->truesize, &sk->sk_wmem_alloc);
/* Build TCP header and checksum it. */
@@ -1840,7 +1839,6 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
while ((skb = tcp_send_head(sk))) {
unsigned int limit;
-
tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
BUG_ON(!tso_segs);
@@ -1869,13 +1867,20 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
break;
}
- /* TSQ : sk_wmem_alloc accounts skb truesize,
- * including skb overhead. But thats OK.
+ /* TCP Small Queues :
+ * Control number of packets in qdisc/devices to two packets / or ~1 ms.
+ * This allows for :
+ * - better RTT estimation and ACK scheduling
+ * - faster recovery
+ * - high rates
*/
- if (atomic_read(&sk->sk_wmem_alloc) >= sysctl_tcp_limit_output_bytes) {
+ limit = max(skb->truesize, sk->sk_pacing_rate >> 10);
+
+ if (atomic_read(&sk->sk_wmem_alloc) > limit) {
set_bit(TSQ_THROTTLED, &tp->tsq_flags);
break;
}
+
limit = mss_now;
if (tso_segs > 1 && !tcp_urg_mode(tp))
limit = tcp_mss_split_point(sk, skb, mss_now,