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Diffstat (limited to 'net/rxrpc/peer_event.c')
-rw-r--r--net/rxrpc/peer_event.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index 7f749505e699..d01eb9a06448 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -348,3 +348,99 @@ void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
trace_rxrpc_rtt_rx(call, why, send_serial, resp_serial, rtt,
usage, avg);
}
+
+/*
+ * Perform keep-alive pings with VERSION packets to keep any NAT alive.
+ */
+void rxrpc_peer_keepalive_worker(struct work_struct *work)
+{
+ struct rxrpc_net *rxnet =
+ container_of(work, struct rxrpc_net, peer_keepalive_work);
+ struct rxrpc_peer *peer;
+ unsigned long delay;
+ ktime_t base, now = ktime_get_real();
+ s64 diff;
+ u8 cursor, slot;
+
+ base = rxnet->peer_keepalive_base;
+ cursor = rxnet->peer_keepalive_cursor;
+
+ _enter("%u,%lld", cursor, ktime_sub(now, base));
+
+next_bucket:
+ diff = ktime_to_ns(ktime_sub(now, base));
+ if (diff < 0)
+ goto resched;
+
+ _debug("at %u", cursor);
+ spin_lock_bh(&rxnet->peer_hash_lock);
+next_peer:
+ if (!rxnet->live) {
+ spin_unlock_bh(&rxnet->peer_hash_lock);
+ goto out;
+ }
+
+ /* Everything in the bucket at the cursor is processed this second; the
+ * bucket at cursor + 1 goes now + 1s and so on...
+ */
+ if (hlist_empty(&rxnet->peer_keepalive[cursor])) {
+ if (hlist_empty(&rxnet->peer_keepalive_new)) {
+ spin_unlock_bh(&rxnet->peer_hash_lock);
+ goto emptied_bucket;
+ }
+
+ hlist_move_list(&rxnet->peer_keepalive_new,
+ &rxnet->peer_keepalive[cursor]);
+ }
+
+ peer = hlist_entry(rxnet->peer_keepalive[cursor].first,
+ struct rxrpc_peer, keepalive_link);
+ hlist_del_init(&peer->keepalive_link);
+ if (!rxrpc_get_peer_maybe(peer))
+ goto next_peer;
+
+ spin_unlock_bh(&rxnet->peer_hash_lock);
+
+ _debug("peer %u {%pISp}", peer->debug_id, &peer->srx.transport);
+
+recalc:
+ diff = ktime_divns(ktime_sub(peer->last_tx_at, base), NSEC_PER_SEC);
+ if (diff < -30 || diff > 30)
+ goto send; /* LSW of 64-bit time probably wrapped on 32-bit */
+ diff += RXRPC_KEEPALIVE_TIME - 1;
+ if (diff < 0)
+ goto send;
+
+ slot = (diff > RXRPC_KEEPALIVE_TIME - 1) ? RXRPC_KEEPALIVE_TIME - 1 : diff;
+ if (slot == 0)
+ goto send;
+
+ /* A transmission to this peer occurred since last we examined it so
+ * put it into the appropriate future bucket.
+ */
+ slot = (slot + cursor) % ARRAY_SIZE(rxnet->peer_keepalive);
+ spin_lock_bh(&rxnet->peer_hash_lock);
+ hlist_add_head(&peer->keepalive_link, &rxnet->peer_keepalive[slot]);
+ rxrpc_put_peer(peer);
+ goto next_peer;
+
+send:
+ rxrpc_send_keepalive(peer);
+ now = ktime_get_real();
+ goto recalc;
+
+emptied_bucket:
+ cursor++;
+ if (cursor >= ARRAY_SIZE(rxnet->peer_keepalive))
+ cursor = 0;
+ base = ktime_add_ns(base, NSEC_PER_SEC);
+ goto next_bucket;
+
+resched:
+ rxnet->peer_keepalive_base = base;
+ rxnet->peer_keepalive_cursor = cursor;
+ delay = nsecs_to_jiffies(-diff) + 1;
+ timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);
+out:
+ _leave("");
+}