On Wed, Jul 15, 2020 at 11:29 AM Maxim Mikityanskiy
<maximmi@xxxxxxxxxxxx> wrote:
>
> On 2020-07-10 17:16, Magnus Karlsson wrote:
> > Move the fill and completion rings from the umem to the buffer
> > pool. This so that we in a later commit can share the umem
> > between multiple HW queue ids. In this case, we need one fill and
> > completion ring per queue id. As the buffer pool is per queue id
> > and napi id this is a natural place for it and one umem
> > struture can be shared between these buffer pools.
> >
> > Signed-off-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
> > ---
> > include/net/xdp_sock.h | 4 ++--
> > include/net/xsk_buff_pool.h | 2 +-
> > net/xdp/xdp_umem.c | 15 ---------------
> > net/xdp/xsk.c | 44 ++++++++++++++++++++++++--------------------
> > net/xdp/xsk_buff_pool.c | 20 +++++++++++++++-----
> > net/xdp/xsk_diag.c | 10 ++++++----
> > 6 files changed, 48 insertions(+), 47 deletions(-)
> >
> > diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
> > index b9bb118..5eb59b7 100644
> > --- a/include/net/xdp_sock.h
> > +++ b/include/net/xdp_sock.h
> > @@ -18,8 +18,6 @@ struct xsk_queue;
> > struct xdp_buff;
> >
> > struct xdp_umem {
> > - struct xsk_queue *fq;
> > - struct xsk_queue *cq;
> > u64 size;
> > u32 headroom;
> > u32 chunk_size;
> > @@ -73,6 +71,8 @@ struct xdp_sock {
> > struct list_head map_list;
> > /* Protects map_list */
> > spinlock_t map_list_lock;
> > + struct xsk_queue *fq_tmp; /* Only as tmp storage before bind */
> > + struct xsk_queue *cq_tmp; /* Only as tmp storage before bind */
> > };
> >
> > #ifdef CONFIG_XDP_SOCKETS
> > diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h
> > index ff8592d5..0423303 100644
> > --- a/include/net/xsk_buff_pool.h
> > +++ b/include/net/xsk_buff_pool.h
> > @@ -30,6 +30,7 @@ struct xdp_buff_xsk {
> >
> > struct xsk_buff_pool {
> > struct xsk_queue *fq;
> > + struct xsk_queue *cq;
> > struct list_head free_list;
> > dma_addr_t *dma_pages;
> > struct xdp_buff_xsk *heads;
> > @@ -57,7 +58,6 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
> > struct xdp_umem *umem);
> > int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev,
> > u16 queue_id, u16 flags);
> > -void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq);
> > void xp_destroy(struct xsk_buff_pool *pool);
> > void xp_release(struct xdp_buff_xsk *xskb);
> > void xp_get_pool(struct xsk_buff_pool *pool);
> > diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
> > index f290345..7d86a63 100644
> > --- a/net/xdp/xdp_umem.c
> > +++ b/net/xdp/xdp_umem.c
> > @@ -85,16 +85,6 @@ static void xdp_umem_release(struct xdp_umem *umem)
> >
> > ida_simple_remove(&umem_ida, umem->id);
> >
> > - if (umem->fq) {
> > - xskq_destroy(umem->fq);
> > - umem->fq = NULL;
> > - }
> > -
> > - if (umem->cq) {
> > - xskq_destroy(umem->cq);
> > - umem->cq = NULL;
> > - }
> > -
> > xdp_umem_unpin_pages(umem);
> >
> > xdp_umem_unaccount_pages(umem);
> > @@ -278,8 +268,3 @@ struct xdp_umem *xdp_umem_create(struct xdp_umem_reg *mr)
> >
> > return umem;
> > }
> > -
> > -bool xdp_umem_validate_queues(struct xdp_umem *umem)
> > -{
> > - return umem->fq && umem->cq;
> > -}
> > diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
> > index caaf298..b44b150 100644
> > --- a/net/xdp/xsk.c
> > +++ b/net/xdp/xsk.c
> > @@ -36,7 +36,7 @@ static DEFINE_PER_CPU(struct list_head, xskmap_flush_list);
> > bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
> > {
> > return READ_ONCE(xs->rx) && READ_ONCE(xs->umem) &&
> > - READ_ONCE(xs->umem->fq);
> > + (xs->pool->fq || READ_ONCE(xs->fq_tmp));
> > }
> >
> > void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool)
> > @@ -46,7 +46,7 @@ void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool)
> > if (umem->need_wakeup & XDP_WAKEUP_RX)
> > return;
> >
> > - umem->fq->ring->flags |= XDP_RING_NEED_WAKEUP;
> > + pool->fq->ring->flags |= XDP_RING_NEED_WAKEUP;
> > umem->need_wakeup |= XDP_WAKEUP_RX;
> > }
> > EXPORT_SYMBOL(xsk_set_rx_need_wakeup);
> > @@ -76,7 +76,7 @@ void xsk_clear_rx_need_wakeup(struct xsk_buff_pool *pool)
> > if (!(umem->need_wakeup & XDP_WAKEUP_RX))
> > return;
> >
> > - umem->fq->ring->flags &= ~XDP_RING_NEED_WAKEUP;
> > + pool->fq->ring->flags &= ~XDP_RING_NEED_WAKEUP;
> > umem->need_wakeup &= ~XDP_WAKEUP_RX;
> > }
> > EXPORT_SYMBOL(xsk_clear_rx_need_wakeup);
> > @@ -254,7 +254,7 @@ static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp,
> > static void xsk_flush(struct xdp_sock *xs)
> > {
> > xskq_prod_submit(xs->rx);
> > - __xskq_cons_release(xs->umem->fq);
> > + __xskq_cons_release(xs->pool->fq);
> > sock_def_readable(&xs->sk);
> > }
> >
> > @@ -297,7 +297,7 @@ void __xsk_map_flush(void)
> >
> > void xsk_tx_completed(struct xsk_buff_pool *pool, u32 nb_entries)
> > {
> > - xskq_prod_submit_n(pool->umem->cq, nb_entries);
> > + xskq_prod_submit_n(pool->cq, nb_entries);
> > }
> > EXPORT_SYMBOL(xsk_tx_completed);
> >
> > @@ -329,7 +329,7 @@ bool xsk_tx_peek_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc)
> > * if there is space in it. This avoids having to implement
> > * any buffering in the Tx path.
> > */
> > - if (xskq_prod_reserve_addr(umem->cq, desc->addr))
> > + if (xskq_prod_reserve_addr(pool->cq, desc->addr))
> > goto out;
> >
> > xskq_cons_release(xs->tx);
> > @@ -367,7 +367,7 @@ static void xsk_destruct_skb(struct sk_buff *skb)
> > unsigned long flags;
> >
> > spin_lock_irqsave(&xs->tx_completion_lock, flags);
> > - xskq_prod_submit_addr(xs->umem->cq, addr);
> > + xskq_prod_submit_addr(xs->pool->cq, addr);
> > spin_unlock_irqrestore(&xs->tx_completion_lock, flags);
> >
> > sock_wfree(skb);
> > @@ -411,7 +411,7 @@ static int xsk_generic_xmit(struct sock *sk)
> > * if there is space in it. This avoids having to implement
> > * any buffering in the Tx path.
> > */
> > - if (unlikely(err) || xskq_prod_reserve(xs->umem->cq)) {
> > + if (unlikely(err) || xskq_prod_reserve(xs->pool->cq)) {
> > kfree_skb(skb);
> > goto out;
> > }
> > @@ -629,6 +629,11 @@ static struct socket *xsk_lookup_xsk_from_fd(int fd)
> > return sock;
> > }
> >
> > +static bool xsk_validate_queues(struct xdp_sock *xs)
> > +{
> > + return xs->fq_tmp && xs->cq_tmp;
> > +}
> > +
> > static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
> > {
> > struct sockaddr_xdp *sxdp = (struct sockaddr_xdp *)addr;
> > @@ -685,6 +690,12 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
> > goto out_unlock;
> > }
> >
> > + if (xs->fq_tmp || xs->cq_tmp) {
> > + /* Do not allow setting your own fq or cq. */
> > + err = -EINVAL;
> > + goto out_unlock;
> > + }
> > +
> > sock = xsk_lookup_xsk_from_fd(sxdp->sxdp_shared_umem_fd);
> > if (IS_ERR(sock)) {
> > err = PTR_ERR(sock);
> > @@ -709,7 +720,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
> > xdp_get_umem(umem_xs->umem);
> > WRITE_ONCE(xs->umem, umem_xs->umem);
> > sockfd_put(sock);
> > - } else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) {
> > + } else if (!xs->umem || !xsk_validate_queues(xs)) {
> > err = -EINVAL;
> > goto out_unlock;
> > } else {
> > @@ -844,11 +855,9 @@ static int xsk_setsockopt(struct socket *sock, int level, int optname,
> > return -EINVAL;
> > }
> >
> > - q = (optname == XDP_UMEM_FILL_RING) ? &xs->umem->fq :
> > - &xs->umem->cq;
> > + q = (optname == XDP_UMEM_FILL_RING) ? &xs->fq_tmp :
> > + &xs->cq_tmp;
> > err = xsk_init_queue(entries, q, true);
> > - if (optname == XDP_UMEM_FILL_RING)
> > - xp_set_fq(xs->pool, *q);
> > mutex_unlock(&xs->mutex);
> > return err;
> > }
> > @@ -995,7 +1004,6 @@ static int xsk_mmap(struct file *file, struct socket *sock,
> > unsigned long size = vma->vm_end - vma->vm_start;
> > struct xdp_sock *xs = xdp_sk(sock->sk);
> > struct xsk_queue *q = NULL;
> > - struct xdp_umem *umem;
> > unsigned long pfn;
> > struct page *qpg;
> >
> > @@ -1007,16 +1015,12 @@ static int xsk_mmap(struct file *file, struct socket *sock,
> > } else if (offset == XDP_PGOFF_TX_RING) {
> > q = READ_ONCE(xs->tx);
> > } else {
> > - umem = READ_ONCE(xs->umem);
> > - if (!umem)
> > - return -EINVAL;
> > -
> > /* Matches the smp_wmb() in XDP_UMEM_REG */
> > smp_rmb();
> > if (offset == XDP_UMEM_PGOFF_FILL_RING)
> > - q = READ_ONCE(umem->fq);
> > + q = READ_ONCE(xs->fq_tmp);
> > else if (offset == XDP_UMEM_PGOFF_COMPLETION_RING)
> > - q = READ_ONCE(umem->cq);
> > + q = READ_ONCE(xs->cq_tmp);
> > }
> >
> > if (!q)
> > diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
> > index d450fb7..32720f2 100644
> > --- a/net/xdp/xsk_buff_pool.c
> > +++ b/net/xdp/xsk_buff_pool.c
> > @@ -66,6 +66,11 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
> > INIT_LIST_HEAD(&pool->free_list);
> > refcount_set(&pool->users, 1);
> >
> > + pool->fq = xs->fq_tmp;
> > + pool->cq = xs->cq_tmp;
> > + xs->fq_tmp = NULL;
> > + xs->cq_tmp = NULL;
> > +
> > for (i = 0; i < pool->free_heads_cnt; i++) {
> > xskb = &pool->heads[i];
> > xskb->pool = pool;
> > @@ -82,11 +87,6 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
> > return NULL;
> > }
> >
> > -void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq)
> > -{
> > - pool->fq = fq;
> > -}
> > -
> > void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
> > {
> > u32 i;
> > @@ -190,6 +190,16 @@ static void xp_release_deferred(struct work_struct *work)
> > xp_clear_dev(pool);
> > rtnl_unlock();
> >
> > + if (pool->fq) {
> > + xskq_destroy(pool->fq);
> > + pool->fq = NULL;
> > + }
> > +
> > + if (pool->cq) {
> > + xskq_destroy(pool->cq);
> > + pool->cq = NULL;
> > + }
> > +
>
> It looks like xskq_destroy is missing for fq_tmp and cq_tmp, which is
> needed in some cases, e.g., if bind() wasn't called at all, or if
> xsk_bind failed with EINVAL.
Thanks Max. Will spin a v3.
/Magnus
> > xdp_put_umem(pool->umem);
> > xp_destroy(pool);
> > }
> > diff --git a/net/xdp/xsk_diag.c b/net/xdp/xsk_diag.c
> > index 0163b26..1936423 100644
> > --- a/net/xdp/xsk_diag.c
> > +++ b/net/xdp/xsk_diag.c
> > @@ -46,6 +46,7 @@ static int xsk_diag_put_rings_cfg(const struct xdp_sock *xs,
> >
> > static int xsk_diag_put_umem(const struct xdp_sock *xs, struct sk_buff *nlskb)
> > {
> > + struct xsk_buff_pool *pool = xs->pool;
> > struct xdp_umem *umem = xs->umem;
> > struct xdp_diag_umem du = {};
> > int err;
> > @@ -67,10 +68,11 @@ static int xsk_diag_put_umem(const struct xdp_sock *xs, struct sk_buff *nlskb)
> >
> > err = nla_put(nlskb, XDP_DIAG_UMEM, sizeof(du), &du);
> >
> > - if (!err && umem->fq)
> > - err = xsk_diag_put_ring(umem->fq, XDP_DIAG_UMEM_FILL_RING, nlskb);
> > - if (!err && umem->cq) {
> > - err = xsk_diag_put_ring(umem->cq, XDP_DIAG_UMEM_COMPLETION_RING,
> > + if (!err && pool->fq)
> > + err = xsk_diag_put_ring(pool->fq,
> > + XDP_DIAG_UMEM_FILL_RING, nlskb);
> > + if (!err && pool->cq) {
> > + err = xsk_diag_put_ring(pool->cq, XDP_DIAG_UMEM_COMPLETION_RING,
> > nlskb);
> > }
> > return err;
> >
>
