xiaomi-sm8450/android_kernel_xiaomi_sm8450
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[TCP]: Don't set SKB owner in tcp_transmit_skb().

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The data itself is already charged to the SKB, doing
the skb_set_owner_w() just generates a lot of noise and
extra atomics we don't really need.

Lmbench improvements on lat_tcp are minimal:

before:
TCP latency using localhost: 23.2701 microseconds
TCP latency using localhost: 23.1994 microseconds
TCP latency using localhost: 23.2257 microseconds

after:
TCP latency using localhost: 22.8380 microseconds
TCP latency using localhost: 22.9465 microseconds
TCP latency using localhost: 22.8462 microseconds

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller
2006-11-09 19:58:25 -08:00
parent ef56e622c6
commit 931731123a
8 changed files with 10 additions and 12 deletions
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3
net/ipv4/tcp_output.c
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@@ -426,7 +426,6 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
th = (struct tcphdr *) skb_push(skb, tcp_header_size);
skb->h.th = th;
skb_set_owner_w(skb, sk);
/* Build TCP header and checksum it. */
th->source = inet->sport;
@@ -479,7 +478,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
if (after(tcb->end_seq, tp->snd_nxt) || tcb->seq == tcb->end_seq)
TCP_INC_STATS(TCP_MIB_OUTSEGS);
err = icsk->icsk_af_ops->queue_xmit(skb, 0);
err = icsk->icsk_af_ops->queue_xmit(skb, sk, 0);
if (likely(err <= 0))
return err;