From a4310fa2f24687888ce80fdb0e88583561a23700 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Wed, 31 Oct 2018 10:37:46 +0100 Subject: can: dev: can_get_echo_skb(): factor out non sending code to __can_get_echo_skb() This patch factors out all non sending parts of can_get_echo_skb() into a seperate function __can_get_echo_skb(), so that it can be re-used in an upcoming patch. Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- include/linux/can/dev.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index a83e1f632eb7..f01623aef2f7 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -169,6 +169,7 @@ void can_change_state(struct net_device *dev, struct can_frame *cf, void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, unsigned int idx); +struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr); unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); void can_free_echo_skb(struct net_device *dev, unsigned int idx); -- cgit v1.3-14-g43fede From 55059f2b7f868cd43b3ad30e28e18347e1b46ace Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Tue, 18 Sep 2018 11:40:38 +0200 Subject: can: rx-offload: introduce can_rx_offload_get_echo_skb() and can_rx_offload_queue_sorted() functions Current CAN framework can't guarantee proper/chronological order of RX and TX-ECHO messages. To make this possible, drivers should use this functions instead of can_get_echo_skb(). Signed-off-by: Oleksij Rempel Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- drivers/net/can/rx-offload.c | 46 ++++++++++++++++++++++++++++++++++++++++++ include/linux/can/rx-offload.h | 4 ++++ 2 files changed, 50 insertions(+) (limited to 'include') diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c index c7d05027a7a0..c368686e2164 100644 --- a/drivers/net/can/rx-offload.c +++ b/drivers/net/can/rx-offload.c @@ -211,6 +211,52 @@ int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload) } EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_fifo); +int can_rx_offload_queue_sorted(struct can_rx_offload *offload, + struct sk_buff *skb, u32 timestamp) +{ + struct can_rx_offload_cb *cb; + unsigned long flags; + + if (skb_queue_len(&offload->skb_queue) > + offload->skb_queue_len_max) + return -ENOMEM; + + cb = can_rx_offload_get_cb(skb); + cb->timestamp = timestamp; + + spin_lock_irqsave(&offload->skb_queue.lock, flags); + __skb_queue_add_sort(&offload->skb_queue, skb, can_rx_offload_compare); + spin_unlock_irqrestore(&offload->skb_queue.lock, flags); + + can_rx_offload_schedule(offload); + + return 0; +} +EXPORT_SYMBOL_GPL(can_rx_offload_queue_sorted); + +unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, + unsigned int idx, u32 timestamp) +{ + struct net_device *dev = offload->dev; + struct net_device_stats *stats = &dev->stats; + struct sk_buff *skb; + u8 len; + int err; + + skb = __can_get_echo_skb(dev, idx, &len); + if (!skb) + return 0; + + err = can_rx_offload_queue_sorted(offload, skb, timestamp); + if (err) { + stats->rx_errors++; + stats->tx_fifo_errors++; + } + + return len; +} +EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb); + int can_rx_offload_irq_queue_err_skb(struct can_rx_offload *offload, struct sk_buff *skb) { if (skb_queue_len(&offload->skb_queue) > diff --git a/include/linux/can/rx-offload.h b/include/linux/can/rx-offload.h index cb31683bbe15..01a7c9e5d8d8 100644 --- a/include/linux/can/rx-offload.h +++ b/include/linux/can/rx-offload.h @@ -41,6 +41,10 @@ int can_rx_offload_add_timestamp(struct net_device *dev, struct can_rx_offload * int can_rx_offload_add_fifo(struct net_device *dev, struct can_rx_offload *offload, unsigned int weight); int can_rx_offload_irq_offload_timestamp(struct can_rx_offload *offload, u64 reg); int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload); +int can_rx_offload_queue_sorted(struct can_rx_offload *offload, + struct sk_buff *skb, u32 timestamp); +unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, + unsigned int idx, u32 timestamp); int can_rx_offload_irq_queue_err_skb(struct can_rx_offload *offload, struct sk_buff *skb); void can_rx_offload_reset(struct can_rx_offload *offload); void can_rx_offload_del(struct can_rx_offload *offload); -- cgit v1.3-14-g43fede From 4530ec36bb1e0d24f41c33229694adacda3d5d89 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Tue, 18 Sep 2018 11:40:40 +0200 Subject: can: rx-offload: rename can_rx_offload_irq_queue_err_skb() to can_rx_offload_queue_tail() This function has nothing todo with error. Signed-off-by: Oleksij Rempel Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- drivers/net/can/flexcan.c | 4 ++-- drivers/net/can/rx-offload.c | 5 +++-- include/linux/can/rx-offload.h | 3 ++- 3 files changed, 7 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 41a175f80c4b..5923bd0ec118 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -610,7 +610,7 @@ static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr) if (tx_errors) dev->stats.tx_errors++; - can_rx_offload_irq_queue_err_skb(&priv->offload, skb); + can_rx_offload_queue_tail(&priv->offload, skb); } static void flexcan_irq_state(struct net_device *dev, u32 reg_esr) @@ -650,7 +650,7 @@ static void flexcan_irq_state(struct net_device *dev, u32 reg_esr) if (unlikely(new_state == CAN_STATE_BUS_OFF)) can_bus_off(dev); - can_rx_offload_irq_queue_err_skb(&priv->offload, skb); + can_rx_offload_queue_tail(&priv->offload, skb); } static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload) diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c index c368686e2164..2ce4fa8698c7 100644 --- a/drivers/net/can/rx-offload.c +++ b/drivers/net/can/rx-offload.c @@ -257,7 +257,8 @@ unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, } EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb); -int can_rx_offload_irq_queue_err_skb(struct can_rx_offload *offload, struct sk_buff *skb) +int can_rx_offload_queue_tail(struct can_rx_offload *offload, + struct sk_buff *skb) { if (skb_queue_len(&offload->skb_queue) > offload->skb_queue_len_max) @@ -268,7 +269,7 @@ int can_rx_offload_irq_queue_err_skb(struct can_rx_offload *offload, struct sk_b return 0; } -EXPORT_SYMBOL_GPL(can_rx_offload_irq_queue_err_skb); +EXPORT_SYMBOL_GPL(can_rx_offload_queue_tail); static int can_rx_offload_init_queue(struct net_device *dev, struct can_rx_offload *offload, unsigned int weight) { diff --git a/include/linux/can/rx-offload.h b/include/linux/can/rx-offload.h index 01a7c9e5d8d8..8268811a697e 100644 --- a/include/linux/can/rx-offload.h +++ b/include/linux/can/rx-offload.h @@ -45,7 +45,8 @@ int can_rx_offload_queue_sorted(struct can_rx_offload *offload, struct sk_buff *skb, u32 timestamp); unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, unsigned int idx, u32 timestamp); -int can_rx_offload_irq_queue_err_skb(struct can_rx_offload *offload, struct sk_buff *skb); +int can_rx_offload_queue_tail(struct can_rx_offload *offload, + struct sk_buff *skb); void can_rx_offload_reset(struct can_rx_offload *offload); void can_rx_offload_del(struct can_rx_offload *offload); void can_rx_offload_enable(struct can_rx_offload *offload); -- cgit v1.3-14-g43fede From 7150ceaacb27f7b3bf494e72cd4be4e11612dfff Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 12 Nov 2018 22:33:22 +0000 Subject: rxrpc: Fix life check The life-checking function, which is used by kAFS to make sure that a call is still live in the event of a pending signal, only samples the received packet serial number counter; it doesn't actually provoke a change in the counter, rather relying on the server to happen to give us a packet in the time window. Fix this by adding a function to force a ping to be transmitted. kAFS then keeps track of whether there's been a stall, and if so, uses the new function to ping the server, resetting the timeout to allow the reply to come back. If there's a stall, a ping and the call is *still* stalled in the same place after another period, then the call will be aborted. Fixes: bc5e3a546d55 ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals") Fixes: f4d15fb6f99a ("rxrpc: Provide functions for allowing cleaner handling of signals") Signed-off-by: David Howells Signed-off-by: David S. Miller --- Documentation/networking/rxrpc.txt | 17 +++++++++++------ fs/afs/rxrpc.c | 11 ++++++++++- include/net/af_rxrpc.h | 3 ++- include/trace/events/rxrpc.h | 2 ++ net/rxrpc/af_rxrpc.c | 27 +++++++++++++++++++++++---- 5 files changed, 48 insertions(+), 12 deletions(-) (limited to 'include') diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt index 605e00cdd6be..89f1302d593a 100644 --- a/Documentation/networking/rxrpc.txt +++ b/Documentation/networking/rxrpc.txt @@ -1056,18 +1056,23 @@ The kernel interface functions are as follows: u32 rxrpc_kernel_check_life(struct socket *sock, struct rxrpc_call *call); + void rxrpc_kernel_probe_life(struct socket *sock, + struct rxrpc_call *call); - This returns a number that is updated when ACKs are received from the peer - (notably including PING RESPONSE ACKs which we can elicit by sending PING - ACKs to see if the call still exists on the server). The caller should - compare the numbers of two calls to see if the call is still alive after - waiting for a suitable interval. + The first function returns a number that is updated when ACKs are received + from the peer (notably including PING RESPONSE ACKs which we can elicit by + sending PING ACKs to see if the call still exists on the server). The + caller should compare the numbers of two calls to see if the call is still + alive after waiting for a suitable interval. This allows the caller to work out if the server is still contactable and if the call is still alive on the server whilst waiting for the server to process a client operation. - This function may transmit a PING ACK. + The second function causes a ping ACK to be transmitted to try to provoke + the peer into responding, which would then cause the value returned by the + first function to change. Note that this must be called in TASK_RUNNING + state. (*) Get reply timestamp. diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c index 59970886690f..a7b44863d502 100644 --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -576,6 +576,7 @@ static long afs_wait_for_call_to_complete(struct afs_call *call, { signed long rtt2, timeout; long ret; + bool stalled = false; u64 rtt; u32 life, last_life; @@ -609,12 +610,20 @@ static long afs_wait_for_call_to_complete(struct afs_call *call, life = rxrpc_kernel_check_life(call->net->socket, call->rxcall); if (timeout == 0 && - life == last_life && signal_pending(current)) + life == last_life && signal_pending(current)) { + if (stalled) break; + __set_current_state(TASK_RUNNING); + rxrpc_kernel_probe_life(call->net->socket, call->rxcall); + timeout = rtt2; + stalled = true; + continue; + } if (life != last_life) { timeout = rtt2; last_life = life; + stalled = false; } timeout = schedule_timeout(timeout); diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h index de587948042a..1adefe42c0a6 100644 --- a/include/net/af_rxrpc.h +++ b/include/net/af_rxrpc.h @@ -77,7 +77,8 @@ int rxrpc_kernel_retry_call(struct socket *, struct rxrpc_call *, struct sockaddr_rxrpc *, struct key *); int rxrpc_kernel_check_call(struct socket *, struct rxrpc_call *, enum rxrpc_call_completion *, u32 *); -u32 rxrpc_kernel_check_life(struct socket *, struct rxrpc_call *); +u32 rxrpc_kernel_check_life(const struct socket *, const struct rxrpc_call *); +void rxrpc_kernel_probe_life(struct socket *, struct rxrpc_call *); u32 rxrpc_kernel_get_epoch(struct socket *, struct rxrpc_call *); bool rxrpc_kernel_get_reply_time(struct socket *, struct rxrpc_call *, ktime_t *); diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h index 573d5b901fb1..5b50fe4906d2 100644 --- a/include/trace/events/rxrpc.h +++ b/include/trace/events/rxrpc.h @@ -181,6 +181,7 @@ enum rxrpc_timer_trace { enum rxrpc_propose_ack_trace { rxrpc_propose_ack_client_tx_end, rxrpc_propose_ack_input_data, + rxrpc_propose_ack_ping_for_check_life, rxrpc_propose_ack_ping_for_keepalive, rxrpc_propose_ack_ping_for_lost_ack, rxrpc_propose_ack_ping_for_lost_reply, @@ -380,6 +381,7 @@ enum rxrpc_tx_point { #define rxrpc_propose_ack_traces \ EM(rxrpc_propose_ack_client_tx_end, "ClTxEnd") \ EM(rxrpc_propose_ack_input_data, "DataIn ") \ + EM(rxrpc_propose_ack_ping_for_check_life, "ChkLife") \ EM(rxrpc_propose_ack_ping_for_keepalive, "KeepAlv") \ EM(rxrpc_propose_ack_ping_for_lost_ack, "LostAck") \ EM(rxrpc_propose_ack_ping_for_lost_reply, "LostRpl") \ diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c index 64362d078da8..a2522f9d71e2 100644 --- a/net/rxrpc/af_rxrpc.c +++ b/net/rxrpc/af_rxrpc.c @@ -375,16 +375,35 @@ EXPORT_SYMBOL(rxrpc_kernel_end_call); * getting ACKs from the server. Returns a number representing the life state * which can be compared to that returned by a previous call. * - * If this is a client call, ping ACKs will be sent to the server to find out - * whether it's still responsive and whether the call is still alive on the - * server. + * If the life state stalls, rxrpc_kernel_probe_life() should be called and + * then 2RTT waited. */ -u32 rxrpc_kernel_check_life(struct socket *sock, struct rxrpc_call *call) +u32 rxrpc_kernel_check_life(const struct socket *sock, + const struct rxrpc_call *call) { return call->acks_latest; } EXPORT_SYMBOL(rxrpc_kernel_check_life); +/** + * rxrpc_kernel_probe_life - Poke the peer to see if it's still alive + * @sock: The socket the call is on + * @call: The call to check + * + * In conjunction with rxrpc_kernel_check_life(), allow a kernel service to + * find out whether a call is still alive by pinging it. This should cause the + * life state to be bumped in about 2*RTT. + * + * The must be called in TASK_RUNNING state on pain of might_sleep() objecting. + */ +void rxrpc_kernel_probe_life(struct socket *sock, struct rxrpc_call *call) +{ + rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false, + rxrpc_propose_ack_ping_for_check_life); + rxrpc_send_ack_packet(call, true, NULL); +} +EXPORT_SYMBOL(rxrpc_kernel_probe_life); + /** * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call. * @sock: The socket the call is on -- cgit v1.3-14-g43fede