From d6833e42786e050e7522d6a91a9361e54085897d Mon Sep 17 00:00:00 2001 From: Sultan Alsawaf Date: Wed, 29 Apr 2020 14:59:20 -0600 Subject: wireguard: send: remove errant newline from packet_encrypt_worker This commit removes a useless newline at the end of a scope, which doesn't add anything in the way of organization or readability. Signed-off-by: Sultan Alsawaf Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller --- drivers/net/wireguard/send.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/net/wireguard/send.c') diff --git a/drivers/net/wireguard/send.c b/drivers/net/wireguard/send.c index 7348c10cbae3..3e030d614df5 100644 --- a/drivers/net/wireguard/send.c +++ b/drivers/net/wireguard/send.c @@ -304,7 +304,6 @@ void wg_packet_encrypt_worker(struct work_struct *work) } wg_queue_enqueue_per_peer(&PACKET_PEER(first)->tx_queue, first, state); - } } -- cgit v1.2.3 From 4005f5c3c9d006157ba716594e0d70c88a235c5e Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Wed, 6 May 2020 15:33:04 -0600 Subject: wireguard: send/receive: cond_resched() when processing worker ringbuffers Users with pathological hardware reported CPU stalls on CONFIG_ PREEMPT_VOLUNTARY=y, because the ringbuffers would stay full, meaning these workers would never terminate. That turned out not to be okay on systems without forced preemption, which Sultan observed. This commit adds a cond_resched() to the bottom of each loop iteration, so that these workers don't hog the core. Note that we don't need this on the napi poll worker, since that terminates after its budget is expended. Suggested-by: Sultan Alsawaf Reported-by: Wang Jian Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller --- drivers/net/wireguard/receive.c | 2 ++ drivers/net/wireguard/send.c | 4 ++++ 2 files changed, 6 insertions(+) (limited to 'drivers/net/wireguard/send.c') diff --git a/drivers/net/wireguard/receive.c b/drivers/net/wireguard/receive.c index 267f202f1931..2566e13a292d 100644 --- a/drivers/net/wireguard/receive.c +++ b/drivers/net/wireguard/receive.c @@ -516,6 +516,8 @@ void wg_packet_decrypt_worker(struct work_struct *work) &PACKET_CB(skb)->keypair->receiving)) ? PACKET_STATE_CRYPTED : PACKET_STATE_DEAD; wg_queue_enqueue_per_peer_napi(skb, state); + if (need_resched()) + cond_resched(); } } diff --git a/drivers/net/wireguard/send.c b/drivers/net/wireguard/send.c index 3e030d614df5..dc3079e17c7f 100644 --- a/drivers/net/wireguard/send.c +++ b/drivers/net/wireguard/send.c @@ -281,6 +281,8 @@ void wg_packet_tx_worker(struct work_struct *work) wg_noise_keypair_put(keypair, false); wg_peer_put(peer); + if (need_resched()) + cond_resched(); } } @@ -304,6 +306,8 @@ void wg_packet_encrypt_worker(struct work_struct *work) } wg_queue_enqueue_per_peer(&PACKET_PEER(first)->tx_queue, first, state); + if (need_resched()) + cond_resched(); } } -- cgit v1.2.3 From 243f2148937adc72bcaaa590d482d599c936efde Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Wed, 6 May 2020 15:33:06 -0600 Subject: wireguard: send/receive: use explicit unlikely branch instead of implicit coalescing It's very unlikely that send will become true. It's nearly always false between 0 and 120 seconds of a session, and in most cases becomes true only between 120 and 121 seconds before becoming false again. So, unlikely(send) is clearly the right option here. What happened before was that we had this complex boolean expression with multiple likely and unlikely clauses nested. Since this is evaluated left-to-right anyway, the whole thing got converted to unlikely. So, we can clean this up to better represent what's going on. The generated code is the same. Suggested-by: Sultan Alsawaf Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller --- drivers/net/wireguard/receive.c | 13 ++++++------- drivers/net/wireguard/send.c | 15 ++++++--------- 2 files changed, 12 insertions(+), 16 deletions(-) (limited to 'drivers/net/wireguard/send.c') diff --git a/drivers/net/wireguard/receive.c b/drivers/net/wireguard/receive.c index 2566e13a292d..3bb5b9ae7cd1 100644 --- a/drivers/net/wireguard/receive.c +++ b/drivers/net/wireguard/receive.c @@ -226,21 +226,20 @@ void wg_packet_handshake_receive_worker(struct work_struct *work) static void keep_key_fresh(struct wg_peer *peer) { struct noise_keypair *keypair; - bool send = false; + bool send; if (peer->sent_lastminute_handshake) return; rcu_read_lock_bh(); keypair = rcu_dereference_bh(peer->keypairs.current_keypair); - if (likely(keypair && READ_ONCE(keypair->sending.is_valid)) && - keypair->i_am_the_initiator && - unlikely(wg_birthdate_has_expired(keypair->sending.birthdate, - REJECT_AFTER_TIME - KEEPALIVE_TIMEOUT - REKEY_TIMEOUT))) - send = true; + send = keypair && READ_ONCE(keypair->sending.is_valid) && + keypair->i_am_the_initiator && + wg_birthdate_has_expired(keypair->sending.birthdate, + REJECT_AFTER_TIME - KEEPALIVE_TIMEOUT - REKEY_TIMEOUT); rcu_read_unlock_bh(); - if (send) { + if (unlikely(send)) { peer->sent_lastminute_handshake = true; wg_packet_send_queued_handshake_initiation(peer, false); } diff --git a/drivers/net/wireguard/send.c b/drivers/net/wireguard/send.c index dc3079e17c7f..6687db699803 100644 --- a/drivers/net/wireguard/send.c +++ b/drivers/net/wireguard/send.c @@ -124,20 +124,17 @@ void wg_packet_send_handshake_cookie(struct wg_device *wg, static void keep_key_fresh(struct wg_peer *peer) { struct noise_keypair *keypair; - bool send = false; + bool send; rcu_read_lock_bh(); keypair = rcu_dereference_bh(peer->keypairs.current_keypair); - if (likely(keypair && READ_ONCE(keypair->sending.is_valid)) && - (unlikely(atomic64_read(&keypair->sending.counter.counter) > - REKEY_AFTER_MESSAGES) || - (keypair->i_am_the_initiator && - unlikely(wg_birthdate_has_expired(keypair->sending.birthdate, - REKEY_AFTER_TIME))))) - send = true; + send = keypair && READ_ONCE(keypair->sending.is_valid) && + (atomic64_read(&keypair->sending.counter.counter) > REKEY_AFTER_MESSAGES || + (keypair->i_am_the_initiator && + wg_birthdate_has_expired(keypair->sending.birthdate, REKEY_AFTER_TIME))); rcu_read_unlock_bh(); - if (send) + if (unlikely(send)) wg_packet_send_queued_handshake_initiation(peer, false); } -- cgit v1.2.3