diff options
| -rw-r--r-- | net/packet/af_packet.c | 76 |
1 files changed, 59 insertions, 17 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ad3d9ff56541..ffa67205f698 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1234,27 +1234,68 @@ static void packet_free_pending(struct packet_sock *po) free_percpu(po->tx_ring.pending_refcnt); } -static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) +#define ROOM_POW_OFF 2 +#define ROOM_NONE 0x0 +#define ROOM_LOW 0x1 +#define ROOM_NORMAL 0x2 + +static bool __tpacket_has_room(struct packet_sock *po, int pow_off) { - struct sock *sk = &po->sk; - bool has_room; + int idx, len; + + len = po->rx_ring.frame_max + 1; + idx = po->rx_ring.head; + if (pow_off) + idx += len >> pow_off; + if (idx >= len) + idx -= len; + return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL); +} - if (po->prot_hook.func != tpacket_rcv) - return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize) - <= sk->sk_rcvbuf; +static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off) +{ + int idx, len; + + len = po->rx_ring.prb_bdqc.knum_blocks; + idx = po->rx_ring.prb_bdqc.kactive_blk_num; + if (pow_off) + idx += len >> pow_off; + if (idx >= len) + idx -= len; + 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) +{ + 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; + if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF)) + return ROOM_NORMAL; + else if (avail > 0) + return ROOM_LOW; + else + return ROOM_NONE; + } spin_lock(&sk->sk_receive_queue.lock); - if (po->tp_version == TPACKET_V3) - has_room = prb_lookup_block(po, &po->rx_ring, - po->rx_ring.prb_bdqc.kactive_blk_num, - TP_STATUS_KERNEL); - else - has_room = packet_lookup_frame(po, &po->rx_ring, - po->rx_ring.head, - TP_STATUS_KERNEL); + if (po->tp_version == TPACKET_V3) { + if (__tpacket_v3_has_room(po, ROOM_POW_OFF)) + ret = ROOM_NORMAL; + else if (__tpacket_v3_has_room(po, 0)) + ret = ROOM_LOW; + } else { + if (__tpacket_has_room(po, ROOM_POW_OFF)) + ret = ROOM_NORMAL; + else if (__tpacket_has_room(po, 0)) + ret = ROOM_LOW; + } spin_unlock(&sk->sk_receive_queue.lock); - return has_room; + return ret; } static void packet_sock_destruct(struct sock *sk) @@ -1325,12 +1366,13 @@ static unsigned int fanout_demux_rollover(struct packet_fanout *f, unsigned int i, j; po = pkt_sk(f->arr[idx]); - if (try_self && packet_rcv_has_room(po, skb)) + if (try_self && packet_rcv_has_room(po, skb) != ROOM_NONE) return idx; i = j = min_t(int, po->rollover->sock, num - 1); do { - if (i != idx && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) { + if (i != idx && + packet_rcv_has_room(pkt_sk(f->arr[i]), skb) == ROOM_NORMAL) { if (i != j) po->rollover->sock = i; return i; |