search for: tun_msg_ptr

On Thu, Sep 06, 2018 at 12:05:23PM +0800, Jason Wang wrote: > This patch introduces to a new tun/tap specific msg_control: > > #define TUN_MSG_UBUF 1 > #define TUN_MSG_PTR 2 > struct tun_msg_ctl { > int type; > void *ptr; > }; > > This allows us to pass different kinds of msg_control through > sendmsg(). The first supported type is ubuf (TUN_MSG_UBUF) which will > be used by the existed vhost_net zerocopy code. The second is XD...

On Thu, Sep 06, 2018 at 12:05:25PM +0800, Jason Wang wrote: > This patch implement TUN_MSG_PTR msg_control type. This type allows > the caller to pass an array of XDP buffs to tuntap through ptr field > of the tun_msg_control. Tap will build skb through those XDP buffers. > > This will avoid lots of indirect calls thus improves the icache > utilization and allows to do XDP ba...

..._of(sock, struct tun_file, socket); struct tun_struct *tun = tun_get(tfile); struct tun_msg_ctl *ctl = m->msg_control; @@ -2477,10 +2469,28 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) if (!tun) return -EBADFD; - if (ctl && ctl->type == TUN_MSG_PTR) { - ret = tun_xdp_one(tun, tfile, ctl->ptr); - if (!ret) - ret = total_len; + if (ctl && ((ctl->type & 0xF) == TUN_MSG_PTR)) { + int n = ctl->type >> 16; + + preempt_disable(); + rcu_read_lock(); + + for (i = 0; i < n; i++) { + struct xdp_buff *x = (struct x...

On Thu, Sep 06, 2018 at 12:05:24PM +0800, Jason Wang wrote: > This patch implement TUN_MSG_PTR msg_control type. This type allows > the caller to pass an array of XDP buffs to tuntap through ptr field > of the tun_msg_control. If an XDP program is attached, tuntap can run > XDP program directly. If not, tuntap will build skb and do a fast > receiving since part of the work has be...

On Wed, Sep 12, 2018 at 11:17:09AM +0800, Jason Wang wrote: > +static void vhost_tx_batch(struct vhost_net *net, > + struct vhost_net_virtqueue *nvq, > + struct socket *sock, > + struct msghdr *msghdr) > +{ > + struct tun_msg_ctl ctl = { > + .type = TUN_MSG_PTR, > + .num = nvq->batched_xdp, > + .ptr = nvq->xdp, > + }; > + int err; > + > + if (nvq->batched_xdp == 0) > + goto signal_used; > + > + msghdr->msg_control = &ctl; > + err = sock->ops->sendmsg(sock, msghdr, 0); > + if (unlikely(err < 0))...

This patch implement TUN_MSG_PTR msg_control type. This type allows the caller to pass an array of XDP buffs to tuntap through ptr field of the tun_msg_control. Tap will build skb through those XDP buffers. This will avoid lots of indirect calls thus improves the icache utilization and allows to do XDP batched flushing when doing...

Hi all: This series tries to batch submitting packets to underlayer socket through msg_control during sendmsg(). This is done by: 1) Doing userspace copy inside vhost_net 2) Build XDP buff 3) Batch at most 64 (VHOST_NET_BATCH) XDP buffs and submit them once through msg_control during sendmsg(). 4) Underlayer sockets can use XDP buffs directly when XDP is enalbed, or build skb based on XDP

This patch implement TUN_MSG_PTR msg_control type. This type allows the caller to pass an array of XDP buffs to tuntap through ptr field of the tun_msg_control. If an XDP program is attached, tuntap can run XDP program directly. If not, tuntap will build skb and do a fast receiving since part of the work has been done by vhost_net...

Hi all: We do not support XDP batching for TUN since it can only receive one packet a time from vhost_net. This series tries to remove this limitation by: - introduce a TUN specific msg_control that can hold a pointer to an array of XDP buffs - try copy and build XDP buff in vhost_net - store XDP buffs in an array and submit them once for every N packets from vhost_net - since TUN can only

Hi all: This series tries to batch submitting packets to underlayer socket through msg_control during sendmsg(). This is done by: 1) Doing userspace copy inside vhost_net 2) Build XDP buff 3) Batch at most 64 (VHOST_NET_BATCH) XDP buffs and submit them once through msg_control during sendmsg(). 4) Underlayer sockets can use XDP buffs directly when XDP is enalbed, or build skb based on XDP

Hi all: This series tries to batch submitting packets to underlayer socket through msg_control during sendmsg(). This is done by: 1) Doing userspace copy inside vhost_net 2) Build XDP buff 3) Batch at most 64 (VHOST_NET_BATCH) XDP buffs and submit them once through msg_control during sendmsg(). 4) Underlayer sockets can use XDP buffs directly when XDP is enalbed, or build skb based on XDP

This patch introduces to a new tun/tap specific msg_control: #define TUN_MSG_UBUF 1 #define TUN_MSG_PTR 2 struct tun_msg_ctl { int type; void *ptr; }; This allows us to pass different kinds of msg_control through sendmsg(). The first supported type is ubuf (TUN_MSG_UBUF) which will be used by the existed vhost_net zerocopy code. The second is XDP buff, which allows vhost_net to pass X...

...tpage->count; + } else { + tun_put_page(tpage); + tpage->page = page; + tpage->count = 1; + } return 0; } } @@ -2480,6 +2500,7 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) return -EBADFD; if (ctl && (ctl->type == TUN_MSG_PTR)) { + struct tun_page tpage = {0}; int n = ctl->num; int flush = 0; @@ -2488,7 +2509,7 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) for (i = 0; i < n; i++) { xdp = &((struct xdp_buff *)ctl->ptr)[i]; - tun_xdp_one(tun, tfile, xdp...

...nvq->done_idx = 0; > } > > +static void vhost_tx_batch(struct vhost_net *net, > + struct vhost_net_virtqueue *nvq, > + struct socket *sock, > + struct msghdr *msghdr) > +{ > + struct tun_msg_ctl ctl = { > + .type = nvq->batched_xdp << 16 | TUN_MSG_PTR, > + .ptr = nvq->xdp, > + }; > + int err; > + > + if (nvq->batched_xdp == 0) > + goto signal_used; > + > + msghdr->msg_control = &ctl; > + err = sock->ops->sendmsg(sock, msghdr, 0); > + if (unlikely(err < 0)) { > + vq_err(&nvq->vq, &q...

...nvq->done_idx = 0; > } > > +static void vhost_tx_batch(struct vhost_net *net, > + struct vhost_net_virtqueue *nvq, > + struct socket *sock, > + struct msghdr *msghdr) > +{ > + struct tun_msg_ctl ctl = { > + .type = nvq->batched_xdp << 16 | TUN_MSG_PTR, > + .ptr = nvq->xdp, > + }; > + int err; > + > + if (nvq->batched_xdp == 0) > + goto signal_used; > + > + msghdr->msg_control = &ctl; > + err = sock->ops->sendmsg(sock, msghdr, 0); > + if (unlikely(err < 0)) { > + vq_err(&nvq->vq, &q...

We do a get_page() which involves a atomic operation. This patch tries to mitigate a per packet atomic operation by maintaining a reference bias which is initially USHRT_MAX. Each time a page is got, instead of calling get_page() we decrease the bias and when we find it's time to use a new page we will decrease the bias at one time through __page_cache_drain_cache(). Testpmd(virtio_user +

...signal_used(struct vhost_net_virtqueue *nvq) nvq->done_idx = 0; } +static void vhost_tx_batch(struct vhost_net *net, + struct vhost_net_virtqueue *nvq, + struct socket *sock, + struct msghdr *msghdr) +{ + struct tun_msg_ctl ctl = { + .type = nvq->batched_xdp << 16 | TUN_MSG_PTR, + .ptr = nvq->xdp, + }; + int err; + + if (nvq->batched_xdp == 0) + goto signal_used; + + msghdr->msg_control = &ctl; + err = sock->ops->sendmsg(sock, msghdr, 0); + if (unlikely(err < 0)) { + vq_err(&nvq->vq, "Fail to batch sending packets\n"); + return;...

...+453,37 @@ static void vhost_net_signal_used(struct vhost_net_virtqueue *nvq) nvq->done_idx = 0; } +static void vhost_tx_batch(struct vhost_net *net, + struct vhost_net_virtqueue *nvq, + struct socket *sock, + struct msghdr *msghdr) +{ + struct tun_msg_ctl ctl = { + .type = TUN_MSG_PTR, + .num = nvq->batched_xdp, + .ptr = nvq->xdp, + }; + int err; + + if (nvq->batched_xdp == 0) + goto signal_used; + + msghdr->msg_control = &ctl; + err = sock->ops->sendmsg(sock, msghdr, 0); + if (unlikely(err < 0)) { + vq_err(&nvq->vq, "Fail to batch sendin...

...gt;> >> +static void vhost_tx_batch(struct vhost_net *net, >> + struct vhost_net_virtqueue *nvq, >> + struct socket *sock, >> + struct msghdr *msghdr) >> +{ >> + struct tun_msg_ctl ctl = { >> + .type = nvq->batched_xdp << 16 | TUN_MSG_PTR, >> + .ptr = nvq->xdp, >> + }; >> + int err; >> + >> + if (nvq->batched_xdp == 0) >> + goto signal_used; >> + >> + msghdr->msg_control = &ctl; >> + err = sock->ops->sendmsg(sock, msghdr, 0); >> + if (unlikely(err <...