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| author | Alexei Starovoitov <ast@kernel.org> | 2018-07-02 18:37:12 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-07-02 18:37:12 -0700 |
| commit | 39d393cf209697babc53f8b29e6aecd6acd8509e (patch) | |
| tree | e8ab093eacf899194e27a120f8ede438ca3fece3 /net | |
| parent | d0fbad0aec1df29717fab736eb24c8a49cf2c70b (diff) | |
| parent | a9744f7ca200c756e6f8c65b633770a2da711651 (diff) | |
| download | lwn-39d393cf209697babc53f8b29e6aecd6acd8509e.tar.gz lwn-39d393cf209697babc53f8b29e6aecd6acd8509e.zip | |
Merge branch 'af_xdp-fixes'
Magnus Karlsson says:
====================
This patch set fixes three bugs in the SKB TX path of AF_XDP.
Details in the individual commits.
The structure of the patch set is as follows:
Patch 1: Fix for lost completion message
Patch 2-3: Fix for possible multiple completions of single packet
Patch 4: Fix potential race during error
Changes from v1:
* Added explanation of race in commit message of patch 4.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/xdp/xsk.c | 10 | ||||
| -rw-r--r-- | net/xdp/xsk_queue.h | 9 |
2 files changed, 9 insertions, 10 deletions
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 59fb7d3c36a3..7d220cbd09b6 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -199,8 +199,11 @@ static void xsk_destruct_skb(struct sk_buff *skb) { u64 addr = (u64)(long)skb_shinfo(skb)->destructor_arg; struct xdp_sock *xs = xdp_sk(skb->sk); + unsigned long flags; + spin_lock_irqsave(&xs->tx_completion_lock, flags); WARN_ON_ONCE(xskq_produce_addr(xs->umem->cq, addr)); + spin_unlock_irqrestore(&xs->tx_completion_lock, flags); sock_wfree(skb); } @@ -268,15 +271,15 @@ static int xsk_generic_xmit(struct sock *sk, struct msghdr *m, skb->destructor = xsk_destruct_skb; err = dev_direct_xmit(skb, xs->queue_id); + xskq_discard_desc(xs->tx); /* Ignore NET_XMIT_CN as packet might have been sent */ if (err == NET_XMIT_DROP || err == NETDEV_TX_BUSY) { - err = -EAGAIN; - /* SKB consumed by dev_direct_xmit() */ + /* SKB completed but not sent */ + err = -EBUSY; goto out; } sent_frame = true; - xskq_discard_desc(xs->tx); } out: @@ -755,6 +758,7 @@ static int xsk_create(struct net *net, struct socket *sock, int protocol, xs = xdp_sk(sk); mutex_init(&xs->mutex); + spin_lock_init(&xs->tx_completion_lock); local_bh_disable(); sock_prot_inuse_add(net, &xsk_proto, 1); diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index ef6a6f0ec949..52ecaf770642 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -62,14 +62,9 @@ static inline u32 xskq_nb_avail(struct xsk_queue *q, u32 dcnt) return (entries > dcnt) ? dcnt : entries; } -static inline u32 xskq_nb_free_lazy(struct xsk_queue *q, u32 producer) -{ - return q->nentries - (producer - q->cons_tail); -} - static inline u32 xskq_nb_free(struct xsk_queue *q, u32 producer, u32 dcnt) { - u32 free_entries = xskq_nb_free_lazy(q, producer); + u32 free_entries = q->nentries - (producer - q->cons_tail); if (free_entries >= dcnt) return free_entries; @@ -129,7 +124,7 @@ static inline int xskq_produce_addr(struct xsk_queue *q, u64 addr) { struct xdp_umem_ring *ring = (struct xdp_umem_ring *)q->ring; - if (xskq_nb_free(q, q->prod_tail, LAZY_UPDATE_THRESHOLD) == 0) + if (xskq_nb_free(q, q->prod_tail, 1) == 0) return -ENOSPC; ring->desc[q->prod_tail++ & q->ring_mask] = addr; |