diff options
-rw-r--r-- | net/packet/af_packet.c | 38 | ||||
-rw-r--r-- | net/packet/internal.h | 1 |
2 files changed, 32 insertions, 7 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ffa6720..3a383fd 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1265,14 +1265,14 @@ static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off) return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL); } -static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) +static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) { struct sock *sk = &po->sk; int ret = ROOM_NONE; if (po->prot_hook.func != tpacket_rcv) { int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc) - - skb->truesize; + - (skb ? skb->truesize : 0); if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF)) return ROOM_NORMAL; else if (avail > 0) @@ -1281,7 +1281,6 @@ static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) return ROOM_NONE; } - spin_lock(&sk->sk_receive_queue.lock); if (po->tp_version == TPACKET_V3) { if (__tpacket_v3_has_room(po, ROOM_POW_OFF)) ret = ROOM_NORMAL; @@ -1293,7 +1292,26 @@ static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) else if (__tpacket_has_room(po, 0)) ret = ROOM_LOW; } - spin_unlock(&sk->sk_receive_queue.lock); + + return ret; +} + +static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) +{ + int ret; + bool has_room; + + if (po->prot_hook.func == tpacket_rcv) { + spin_lock(&po->sk.sk_receive_queue.lock); + ret = __packet_rcv_has_room(po, skb); + spin_unlock(&po->sk.sk_receive_queue.lock); + } else { + ret = __packet_rcv_has_room(po, skb); + } + + has_room = ret == ROOM_NORMAL; + if (po->pressure == has_room) + xchg(&po->pressure, !has_room); return ret; } @@ -1362,7 +1380,7 @@ static unsigned int fanout_demux_rollover(struct packet_fanout *f, unsigned int idx, bool try_self, unsigned int num) { - struct packet_sock *po; + struct packet_sock *po, *po_next; unsigned int i, j; po = pkt_sk(f->arr[idx]); @@ -1371,8 +1389,9 @@ static unsigned int fanout_demux_rollover(struct packet_fanout *f, i = j = min_t(int, po->rollover->sock, num - 1); do { - if (i != idx && - packet_rcv_has_room(pkt_sk(f->arr[i]), skb) == ROOM_NORMAL) { + po_next = pkt_sk(f->arr[i]); + if (po_next != po && !po_next->pressure && + packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) { if (i != j) po->rollover->sock = i; return i; @@ -3000,6 +3019,9 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, if (skb == NULL) goto out; + if (pkt_sk(sk)->pressure) + packet_rcv_has_room(pkt_sk(sk), NULL); + if (pkt_sk(sk)->has_vnet_hdr) { struct virtio_net_hdr vnet_hdr = { 0 }; @@ -3755,6 +3777,8 @@ static unsigned int packet_poll(struct file *file, struct socket *sock, TP_STATUS_KERNEL)) mask |= POLLIN | POLLRDNORM; } + if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL) + xchg(&po->pressure, 0); spin_unlock_bh(&sk->sk_receive_queue.lock); spin_lock_bh(&sk->sk_write_queue.lock); if (po->tx_ring.pg_vec) { diff --git a/net/packet/internal.h b/net/packet/internal.h index a9d33a2..22d7d77 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -105,6 +105,7 @@ struct packet_sock { auxdata:1, origdev:1, has_vnet_hdr:1; + int pressure; int ifindex; /* bound device */ __be16 num; struct packet_rollover *rollover; |