| Message ID | 20250228100730.670587-1-dqfext@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [RFC,net-next,v3] ppp: use IFF_NO_QUEUE in virtual interfaces | expand |
Qingfang Deng <dqfext@gmail.com> writes: > For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly > forwards packets to the underlying network stack and never returns > anything other than 1. So these interfaces do not require a qdisc, > and the IFF_NO_QUEUE flag should be set. > > Introduces a direct_xmit flag in struct ppp_channel to indicate when > IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel() > for relevant protocols. > > Signed-off-by: Qingfang Deng <dqfext@gmail.com> > --- > v3: > Move direct_xmit above the unused "latency" member to avoid > confusion. Should I remove it instead? If it really is unused, I think removing it is better to remove it, yeah :) -Toke
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 6220866258fc..815108c98b78 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -3493,6 +3493,10 @@ ppp_connect_channel(struct channel *pch, int unit) ret = -ENOTCONN; goto outl; } + if (pch->chan->direct_xmit) + ppp->dev->priv_flags |= IFF_NO_QUEUE; + else + ppp->dev->priv_flags &= ~IFF_NO_QUEUE; spin_unlock_bh(&pch->downl); if (pch->file.hdrlen > ppp->file.hdrlen) ppp->file.hdrlen = pch->file.hdrlen; diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c index 2ea4f4890d23..68e631718ab0 100644 --- a/drivers/net/ppp/pppoe.c +++ b/drivers/net/ppp/pppoe.c @@ -693,6 +693,7 @@ static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2; po->chan.private = sk; po->chan.ops = &pppoe_chan_ops; + po->chan.direct_xmit = true; error = ppp_register_net_channel(dev_net(dev), &po->chan); if (error) { diff --git a/drivers/net/ppp/pptp.c b/drivers/net/ppp/pptp.c index 689687bd2574..5feaa70b5f47 100644 --- a/drivers/net/ppp/pptp.c +++ b/drivers/net/ppp/pptp.c @@ -465,6 +465,7 @@ static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.mtu -= PPTP_HEADER_OVERHEAD; po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header); + po->chan.direct_xmit = true; error = ppp_register_channel(&po->chan); if (error) { pr_err("PPTP: failed to register PPP channel (%d)\n", error); diff --git a/include/linux/ppp_channel.h b/include/linux/ppp_channel.h index 45e6e427ceb8..53b62e145078 100644 --- a/include/linux/ppp_channel.h +++ b/include/linux/ppp_channel.h @@ -42,6 +42,7 @@ struct ppp_channel { int hdrlen; /* amount of headroom channel needs */ void *ppp; /* opaque to channel */ int speed; /* transfer rate (bytes/second) */ + bool direct_xmit; /* no qdisc, xmit directly */ /* the following is not used at present */ int latency; /* overhead time in milliseconds */ }; diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 53baf2dd5d5d..fc5c2fd8f34c 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -806,6 +806,7 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.private = sk; po->chan.ops = &pppol2tp_chan_ops; po->chan.mtu = pppol2tp_tunnel_mtu(tunnel); + po->chan.direct_xmit = true; error = ppp_register_net_channel(sock_net(sk), &po->chan); if (error) {
For PPPoE, PPTP, and PPPoL2TP, the start_xmit() function directly forwards packets to the underlying network stack and never returns anything other than 1. So these interfaces do not require a qdisc, and the IFF_NO_QUEUE flag should be set. Introduces a direct_xmit flag in struct ppp_channel to indicate when IFF_NO_QUEUE should be applied. The flag is set in ppp_connect_channel() for relevant protocols. Signed-off-by: Qingfang Deng <dqfext@gmail.com> --- v3: Move direct_xmit above the unused "latency" member to avoid confusion. Should I remove it instead? drivers/net/ppp/ppp_generic.c | 4 ++++ drivers/net/ppp/pppoe.c | 1 + drivers/net/ppp/pptp.c | 1 + include/linux/ppp_channel.h | 1 + net/l2tp/l2tp_ppp.c | 1 + 5 files changed, 8 insertions(+)