* [PATCH v3 net-next 1/2] tcp: use data length instead of skb->len in tcp_probe
@ 2018-05-28 15:35 Yafang Shao
2018-05-28 15:35 ` [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path Yafang Shao
0 siblings, 1 reply; 6+ messages in thread
From: Yafang Shao @ 2018-05-28 15:35 UTC (permalink / raw)
To: songliubraving, edumazet, davem; +Cc: netdev, linux-kernel, Yafang Shao
At this point skb->len is including tcp header length, so it is meaningless
to user. data length could be more helpful, with which we can easily filter
out the packet without payload.
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
v3: tcp_hdr() is a little expensive than skb->data, so replace it with
skb->data.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
include/trace/events/tcp.h | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index c1a5284..7ff0446 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -236,7 +236,7 @@
__field(__u16, sport)
__field(__u16, dport)
__field(__u32, mark)
- __field(__u16, length)
+ __field(__u16, data_len)
__field(__u32, snd_nxt)
__field(__u32, snd_una)
__field(__u32, snd_cwnd)
@@ -250,6 +250,7 @@
TP_fast_assign(
const struct tcp_sock *tp = tcp_sk(sk);
const struct inet_sock *inet = inet_sk(sk);
+ const struct tcphdr *th = (const struct tcphdr *)skb->data;
memset(__entry->saddr, 0, sizeof(struct sockaddr_in6));
memset(__entry->daddr, 0, sizeof(struct sockaddr_in6));
@@ -261,7 +262,7 @@
__entry->dport = ntohs(inet->inet_dport);
__entry->mark = skb->mark;
- __entry->length = skb->len;
+ __entry->data_len = skb->len - __tcp_hdrlen(th);
__entry->snd_nxt = tp->snd_nxt;
__entry->snd_una = tp->snd_una;
__entry->snd_cwnd = tp->snd_cwnd;
@@ -272,9 +273,9 @@
__entry->sock_cookie = sock_gen_cookie(sk);
),
- TP_printk("src=%pISpc dest=%pISpc mark=%#x length=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
+ TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
__entry->saddr, __entry->daddr, __entry->mark,
- __entry->length, __entry->snd_nxt, __entry->snd_una,
+ __entry->data_len, __entry->snd_nxt, __entry->snd_una,
__entry->snd_cwnd, __entry->ssthresh, __entry->snd_wnd,
__entry->srtt, __entry->rcv_wnd, __entry->sock_cookie)
);
--
1.8.3.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path
2018-05-28 15:35 [PATCH v3 net-next 1/2] tcp: use data length instead of skb->len in tcp_probe Yafang Shao
@ 2018-05-28 15:35 ` Yafang Shao
2018-05-28 16:36 ` Eric Dumazet
0 siblings, 1 reply; 6+ messages in thread
From: Yafang Shao @ 2018-05-28 15:35 UTC (permalink / raw)
To: songliubraving, edumazet, davem; +Cc: netdev, linux-kernel, Yafang Shao
This is additional to the commit ea1627c20c34 ("tcp: minor optimizations around tcp_hdr() usage").
At this point, skb->data is same with tcp_hdr() as tcp header has not
been pulled yet.
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
net/ipv4/tcp_ipv4.c | 2 +-
net/ipv6/tcp_ipv6.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index adbdb50..d179386 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1486,7 +1486,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
sk->sk_rx_dst = NULL;
}
}
- tcp_rcv_established(sk, skb, tcp_hdr(skb));
+ tcp_rcv_established(sk, skb, (const struct tcphdr *)skb->data);
return 0;
}
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7d47c2b..1c633ff 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1322,7 +1322,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
}
}
- tcp_rcv_established(sk, skb, tcp_hdr(skb));
+ tcp_rcv_established(sk, skb, (const struct tcphdr *)skb->data);
if (opt_skb)
goto ipv6_pktoptions;
return 0;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path
2018-05-28 15:35 ` [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path Yafang Shao
@ 2018-05-28 16:36 ` Eric Dumazet
2018-05-29 0:41 ` Yafang Shao
0 siblings, 1 reply; 6+ messages in thread
From: Eric Dumazet @ 2018-05-28 16:36 UTC (permalink / raw)
To: laoar.shao; +Cc: songliubraving, David Miller, netdev, LKML
On Mon, May 28, 2018 at 8:36 AM Yafang Shao <laoar.shao@gmail.com> wrote:
> This is additional to the commit ea1627c20c34 ("tcp: minor optimizations
around tcp_hdr() usage").
> At this point, skb->data is same with tcp_hdr() as tcp header has not
> been pulled yet.
> Cc: Eric Dumazet <edumazet@google.com>
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> ---
> net/ipv4/tcp_ipv4.c | 2 +-
> net/ipv6/tcp_ipv6.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index adbdb50..d179386 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -1486,7 +1486,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff
*skb)
> sk->sk_rx_dst = NULL;
> }
> }
> - tcp_rcv_established(sk, skb, tcp_hdr(skb));
> + tcp_rcv_established(sk, skb, (const struct tcphdr
*)skb->data);
> return 0;
> }
> diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
> index 7d47c2b..1c633ff 100644
> --- a/net/ipv6/tcp_ipv6.c
> +++ b/net/ipv6/tcp_ipv6.c
> @@ -1322,7 +1322,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct
sk_buff *skb)
> }
> }
> - tcp_rcv_established(sk, skb, tcp_hdr(skb));
> + tcp_rcv_established(sk, skb, (const struct tcphdr
*)skb->data);
> if (opt_skb)
> goto ipv6_pktoptions;
> return 0;
> --
> 1.8.3.1
I would rather remove the third parameter of tcp_rcv_established() instead
of duplicating the cast.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path
2018-05-28 16:36 ` Eric Dumazet
@ 2018-05-29 0:41 ` Yafang Shao
2018-05-29 4:53 ` Eric Dumazet
0 siblings, 1 reply; 6+ messages in thread
From: Yafang Shao @ 2018-05-29 0:41 UTC (permalink / raw)
To: Eric Dumazet; +Cc: Song Liu, David Miller, netdev, LKML
On Tue, May 29, 2018 at 12:36 AM, Eric Dumazet <edumazet@google.com> wrote:
> On Mon, May 28, 2018 at 8:36 AM Yafang Shao <laoar.shao@gmail.com> wrote:
>
>> This is additional to the commit ea1627c20c34 ("tcp: minor optimizations
> around tcp_hdr() usage").
>> At this point, skb->data is same with tcp_hdr() as tcp header has not
>> been pulled yet.
>
>> Cc: Eric Dumazet <edumazet@google.com>
>> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
>> ---
>> net/ipv4/tcp_ipv4.c | 2 +-
>> net/ipv6/tcp_ipv6.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>
>> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
>> index adbdb50..d179386 100644
>> --- a/net/ipv4/tcp_ipv4.c
>> +++ b/net/ipv4/tcp_ipv4.c
>> @@ -1486,7 +1486,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff
> *skb)
>> sk->sk_rx_dst = NULL;
>> }
>> }
>> - tcp_rcv_established(sk, skb, tcp_hdr(skb));
>> + tcp_rcv_established(sk, skb, (const struct tcphdr
> *)skb->data);
>> return 0;
>> }
>
>> diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
>> index 7d47c2b..1c633ff 100644
>> --- a/net/ipv6/tcp_ipv6.c
>> +++ b/net/ipv6/tcp_ipv6.c
>> @@ -1322,7 +1322,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct
> sk_buff *skb)
>> }
>> }
>
>> - tcp_rcv_established(sk, skb, tcp_hdr(skb));
>> + tcp_rcv_established(sk, skb, (const struct tcphdr
> *)skb->data);
>> if (opt_skb)
>> goto ipv6_pktoptions;
>> return 0;
>> --
>> 1.8.3.1
>
>
> I would rather remove the third parameter of tcp_rcv_established() instead
> of duplicating the cast.
OK.
And what about introducing a new helper tcp_hdr_fast() ?
/* use it when tcp header has not been pulled yet */
static inline struct tcphdr *tcp_hdr_fast(const struct sk_buff *skb)
{
return (const struct tcphdr *)skb->data;
}
That could help us to use this optimized one instead of the original
one if possilbe.
Thanks
Yafang
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path
2018-05-29 0:41 ` Yafang Shao
@ 2018-05-29 4:53 ` Eric Dumazet
2018-05-29 11:08 ` Yafang Shao
0 siblings, 1 reply; 6+ messages in thread
From: Eric Dumazet @ 2018-05-29 4:53 UTC (permalink / raw)
To: Yafang Shao, Eric Dumazet; +Cc: Song Liu, David Miller, netdev, LKML
On 05/28/2018 05:41 PM, Yafang Shao wrote:
> OK.
>
> And what about introducing a new helper tcp_hdr_fast() ?
>
> /* use it when tcp header has not been pulled yet */
> static inline struct tcphdr *tcp_hdr_fast(const struct sk_buff *skb)
>
> {
>
> return (const struct tcphdr *)skb->data;
>
> }
>
>
> That could help us to use this optimized one instead of the original
> one if possilbe.
I would rather not add such macro...
The call site needs to know what is going on, so having a macro like that would not help.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path
2018-05-29 4:53 ` Eric Dumazet
@ 2018-05-29 11:08 ` Yafang Shao
0 siblings, 0 replies; 6+ messages in thread
From: Yafang Shao @ 2018-05-29 11:08 UTC (permalink / raw)
To: Eric Dumazet; +Cc: Eric Dumazet, Song Liu, David Miller, netdev, LKML
On Tue, May 29, 2018 at 12:53 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
>
> On 05/28/2018 05:41 PM, Yafang Shao wrote:
>
>> OK.
>>
>> And what about introducing a new helper tcp_hdr_fast() ?
>>
>> /* use it when tcp header has not been pulled yet */
>> static inline struct tcphdr *tcp_hdr_fast(const struct sk_buff *skb)
>>
>> {
>>
>> return (const struct tcphdr *)skb->data;
>>
>> }
>>
>>
>> That could help us to use this optimized one instead of the original
>> one if possilbe.
>
>
> I would rather not add such macro...
>
> The call site needs to know what is going on, so having a macro like that would not help.
OK
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2018-05-29 11:09 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-05-28 15:35 [PATCH v3 net-next 1/2] tcp: use data length instead of skb->len in tcp_probe Yafang Shao
2018-05-28 15:35 ` [PATCH v3 net-next 2/2] tcp: minor optimization around tcp_hdr() usage in tcp receive path Yafang Shao
2018-05-28 16:36 ` Eric Dumazet
2018-05-29 0:41 ` Yafang Shao
2018-05-29 4:53 ` Eric Dumazet
2018-05-29 11:08 ` Yafang Shao
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