* [PATCH net-next 1/3] net: do not use skb_mac_header() in qdisc_pkt_len_init()
2023-03-21 16:45 [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Eric Dumazet
@ 2023-03-21 16:45 ` Eric Dumazet
2023-03-22 11:25 ` Simon Horman
2023-03-21 16:45 ` [PATCH net-next 2/3] sch_cake: do not use skb_mac_header() in cake_overhead() Eric Dumazet
` (3 subsequent siblings)
4 siblings, 1 reply; 10+ messages in thread
From: Eric Dumazet @ 2023-03-21 16:45 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski, Paolo Abeni
Cc: Simon Horman, netdev, eric.dumazet, Eric Dumazet
We want to remove our use of skb_mac_header() in tx paths,
eg remove skb_reset_mac_header() from __dev_queue_xmit().
Idea is that ndo_start_xmit() can get the mac header
simply looking at skb->data.
Signed-off-by: Eric Dumazet <edumazet@google•com>
---
net/core/dev.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index c7853192563d2ee6cd43293c84b9ae5073346580..c610efc5fcd60247799c6ee7fd1b3fb429cabfb5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3733,25 +3733,25 @@ static void qdisc_pkt_len_init(struct sk_buff *skb)
* we add to pkt_len the headers size of all segments
*/
if (shinfo->gso_size && skb_transport_header_was_set(skb)) {
- unsigned int hdr_len;
u16 gso_segs = shinfo->gso_segs;
+ unsigned int hdr_len;
/* mac layer + network layer */
- hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
+ hdr_len = skb_transport_offset(skb);
/* + transport layer */
if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
const struct tcphdr *th;
struct tcphdr _tcphdr;
- th = skb_header_pointer(skb, skb_transport_offset(skb),
+ th = skb_header_pointer(skb, hdr_len,
sizeof(_tcphdr), &_tcphdr);
if (likely(th))
hdr_len += __tcp_hdrlen(th);
} else {
struct udphdr _udphdr;
- if (skb_header_pointer(skb, skb_transport_offset(skb),
+ if (skb_header_pointer(skb, hdr_len,
sizeof(_udphdr), &_udphdr))
hdr_len += sizeof(struct udphdr);
}
--
2.40.0.rc2.332.ga46443480c-goog
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH net-next 2/3] sch_cake: do not use skb_mac_header() in cake_overhead()
2023-03-21 16:45 [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Eric Dumazet
2023-03-21 16:45 ` [PATCH net-next 1/3] net: do not use skb_mac_header() in qdisc_pkt_len_init() Eric Dumazet
@ 2023-03-21 16:45 ` Eric Dumazet
2023-03-22 11:26 ` Simon Horman
2023-03-21 16:45 ` [PATCH net-next 3/3] net/sched: remove two skb_mac_header() uses Eric Dumazet
` (2 subsequent siblings)
4 siblings, 1 reply; 10+ messages in thread
From: Eric Dumazet @ 2023-03-21 16:45 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski, Paolo Abeni
Cc: Simon Horman, netdev, eric.dumazet, Eric Dumazet
We want to remove our use of skb_mac_header() in tx paths,
eg remove skb_reset_mac_header() from __dev_queue_xmit().
Idea is that ndo_start_xmit() can get the mac header
simply looking at skb->data.
Signed-off-by: Eric Dumazet <edumazet@google•com>
---
net/sched/sch_cake.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index 7970217b565a4ebbee3797ec0e5fb5667c5be795..891e007d5c0bf972a686b892c13d647e46b3274b 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -1360,7 +1360,7 @@ static u32 cake_overhead(struct cake_sched_data *q, const struct sk_buff *skb)
return cake_calc_overhead(q, len, off);
/* borrowed from qdisc_pkt_len_init() */
- hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
+ hdr_len = skb_transport_offset(skb);
/* + transport layer */
if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 |
@@ -1368,14 +1368,14 @@ static u32 cake_overhead(struct cake_sched_data *q, const struct sk_buff *skb)
const struct tcphdr *th;
struct tcphdr _tcphdr;
- th = skb_header_pointer(skb, skb_transport_offset(skb),
+ th = skb_header_pointer(skb, hdr_len,
sizeof(_tcphdr), &_tcphdr);
if (likely(th))
hdr_len += __tcp_hdrlen(th);
} else {
struct udphdr _udphdr;
- if (skb_header_pointer(skb, skb_transport_offset(skb),
+ if (skb_header_pointer(skb, hdr_len,
sizeof(_udphdr), &_udphdr))
hdr_len += sizeof(struct udphdr);
}
--
2.40.0.rc2.332.ga46443480c-goog
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH net-next 3/3] net/sched: remove two skb_mac_header() uses
2023-03-21 16:45 [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Eric Dumazet
2023-03-21 16:45 ` [PATCH net-next 1/3] net: do not use skb_mac_header() in qdisc_pkt_len_init() Eric Dumazet
2023-03-21 16:45 ` [PATCH net-next 2/3] sch_cake: do not use skb_mac_header() in cake_overhead() Eric Dumazet
@ 2023-03-21 16:45 ` Eric Dumazet
2023-03-22 11:26 ` Simon Horman
2023-03-21 17:13 ` [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Vladimir Oltean
2023-03-23 5:50 ` patchwork-bot+netdevbpf
4 siblings, 1 reply; 10+ messages in thread
From: Eric Dumazet @ 2023-03-21 16:45 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski, Paolo Abeni
Cc: Simon Horman, netdev, eric.dumazet, Eric Dumazet
tcf_mirred_act() and tcf_mpls_act() can use skb_network_offset()
instead of relying on skb_mac_header().
Signed-off-by: Eric Dumazet <edumazet@google•com>
---
net/sched/act_mirred.c | 2 +-
net/sched/act_mpls.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 8037ec9b1d311486d803159b3f2f77eedf6b31d3..ec43764e92e7ba66586310628d78a6b184957fd2 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -295,7 +295,7 @@ TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb,
at_nh = skb->data == skb_network_header(skb);
if (at_nh != expects_nh) {
mac_len = skb_at_tc_ingress(skb) ? skb->mac_len :
- skb_network_header(skb) - skb_mac_header(skb);
+ skb_network_offset(skb);
if (expects_nh) {
/* target device/action expect data at nh */
skb_pull_rcsum(skb2, mac_len);
diff --git a/net/sched/act_mpls.c b/net/sched/act_mpls.c
index 809f7928a1be622671e47b8bdf384a8a10349926..1010dc632874ec5f4f0517f0512ab3ed30f14e24 100644
--- a/net/sched/act_mpls.c
+++ b/net/sched/act_mpls.c
@@ -69,7 +69,7 @@ TC_INDIRECT_SCOPE int tcf_mpls_act(struct sk_buff *skb,
skb_push_rcsum(skb, skb->mac_len);
mac_len = skb->mac_len;
} else {
- mac_len = skb_network_header(skb) - skb_mac_header(skb);
+ mac_len = skb_network_offset(skb);
}
ret = READ_ONCE(m->tcf_action);
--
2.40.0.rc2.332.ga46443480c-goog
^ permalink raw reply related [flat|nested] 10+ messages in thread* Re: [PATCH net-next 0/3] net: remove some skb_mac_header assumptions
2023-03-21 16:45 [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Eric Dumazet
` (2 preceding siblings ...)
2023-03-21 16:45 ` [PATCH net-next 3/3] net/sched: remove two skb_mac_header() uses Eric Dumazet
@ 2023-03-21 17:13 ` Vladimir Oltean
2023-03-21 18:41 ` Eric Dumazet
2023-03-23 5:50 ` patchwork-bot+netdevbpf
4 siblings, 1 reply; 10+ messages in thread
From: Vladimir Oltean @ 2023-03-21 17:13 UTC (permalink / raw)
To: Eric Dumazet
Cc: David S . Miller, Jakub Kicinski, Paolo Abeni, Simon Horman,
netdev, eric.dumazet
Hi Eric,
On Tue, Mar 21, 2023 at 04:45:16PM +0000, Eric Dumazet wrote:
> Historically, we tried o maintain skb_mac_header available in most of
> networking paths.
>
> When reaching ndo_start_xmit() handlers, skb_mac_header() should always
> be skb->data.
>
> With recent additions of skb_mac_header_was_set() and
> DEBUG_NET_WARN_ON_ONCE() in skb_mac_header(), we can attempt
> to remove our reliance on skb_mac_header in TX paths.
>
> When this effort completes we will remove skb_reset_mac_header()
> from __dev_queue_xmit() and replace it by
> skb_unset_mac_header() on DEBUG_NET builds.
>
> Eric Dumazet (3):
> net: do not use skb_mac_header() in qdisc_pkt_len_init()
> sch_cake: do not use skb_mac_header() in cake_overhead()
> net/sched: remove two skb_mac_header() uses
>
> net/core/dev.c | 8 ++++----
> net/sched/act_mirred.c | 2 +-
> net/sched/act_mpls.c | 2 +-
> net/sched/sch_cake.c | 6 +++---
> 4 files changed, 9 insertions(+), 9 deletions(-)
>
> --
> 2.40.0.rc2.332.ga46443480c-goog
>
skb_mac_header() shows quite a few hits in net/dsa/ as well, in functions
that contain "xmit" in the name. Should those be changed as well?
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH net-next 0/3] net: remove some skb_mac_header assumptions
2023-03-21 17:13 ` [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Vladimir Oltean
@ 2023-03-21 18:41 ` Eric Dumazet
0 siblings, 0 replies; 10+ messages in thread
From: Eric Dumazet @ 2023-03-21 18:41 UTC (permalink / raw)
To: Vladimir Oltean
Cc: David S . Miller, Jakub Kicinski, Paolo Abeni, Simon Horman,
netdev, eric.dumazet
On Tue, Mar 21, 2023 at 10:13 AM Vladimir Oltean <olteanv@gmail•com> wrote:
>
> Hi Eric,
>
> skb_mac_header() shows quite a few hits in net/dsa/ as well, in functions
> that contain "xmit" in the name. Should those be changed as well?
Hi Vladimir.
Yes, any help that you can provide (especially if you can test
patches) will be much welcomed.
Thanks !
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH net-next 0/3] net: remove some skb_mac_header assumptions
2023-03-21 16:45 [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Eric Dumazet
` (3 preceding siblings ...)
2023-03-21 17:13 ` [PATCH net-next 0/3] net: remove some skb_mac_header assumptions Vladimir Oltean
@ 2023-03-23 5:50 ` patchwork-bot+netdevbpf
4 siblings, 0 replies; 10+ messages in thread
From: patchwork-bot+netdevbpf @ 2023-03-23 5:50 UTC (permalink / raw)
To: Eric Dumazet; +Cc: davem, kuba, pabeni, simon.horman, netdev, eric.dumazet
Hello:
This series was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel•org>:
On Tue, 21 Mar 2023 16:45:16 +0000 you wrote:
> Historically, we tried o maintain skb_mac_header available in most of
> networking paths.
>
> When reaching ndo_start_xmit() handlers, skb_mac_header() should always
> be skb->data.
>
> With recent additions of skb_mac_header_was_set() and
> DEBUG_NET_WARN_ON_ONCE() in skb_mac_header(), we can attempt
> to remove our reliance on skb_mac_header in TX paths.
>
> [...]
Here is the summary with links:
- [net-next,1/3] net: do not use skb_mac_header() in qdisc_pkt_len_init()
https://git.kernel.org/netdev/net-next/c/f5fca219ad45
- [net-next,2/3] sch_cake: do not use skb_mac_header() in cake_overhead()
https://git.kernel.org/netdev/net-next/c/e495a9673caf
- [net-next,3/3] net/sched: remove two skb_mac_header() uses
https://git.kernel.org/netdev/net-next/c/b3be94885af4
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 10+ messages in thread