recieve: disable NAPI busy polling

This avoids adding one reference per peer to the napi_hash hashtable, as
normally done by netif_napi_add(). Since we potentially could have up to
2^20 peers this would make busy polling very slow globally.

This approach is preferable to having only a single napi struct because
we get one gro_list per peer, which means packets can be combined nicely
even if we have a large number of peers.

This is also done by gro_cells_init() in net/core/gro_cells.c .

Signed-off-by: Thomas Gschwantner <tharre3@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/peer.c b/src/peer.c
index 3d2fff0..e8081f5 100644
--- a/src/peer.c
+++ b/src/peer.c
@@ -56,6 +56,7 @@ struct wireguard_peer *peer_create(struct wireguard_device *wg, const u8 public_
 	list_add_tail(&peer->peer_list, &wg->peer_list);
 	pubkey_hashtable_add(&wg->peer_hashtable, peer);
 	peer->last_sent_handshake = ktime_get_boot_fast_ns() - (u64)(REKEY_TIMEOUT + 1) * NSEC_PER_SEC;
+	set_bit(NAPI_STATE_NO_BUSY_POLL, &peer->napi.state);
 	netif_napi_add(wg->dev, &peer->napi, packet_rx_poll, NAPI_POLL_WEIGHT);
 	napi_enable(&peer->napi);
 	pr_debug("%s: Peer %llu created\n", wg->dev->name, peer->internal_id);