diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt index 1fb5c553aedd..b5407163d53b 100644 --- a/Documentation/networking/rxrpc.txt +++ b/Documentation/networking/rxrpc.txt @@ -280,6 +280,18 @@ Interaction with the user of the RxRPC socket: nominated by a socket option. +Notes on sendmsg: + + (*) MSG_WAITALL can be set to tell sendmsg to ignore signals if the peer is + making progress at accepting packets within a reasonable time such that we + manage to queue up all the data for transmission. This requires the + client to accept at least one packet per 2*RTT time period. + + If this isn't set, sendmsg() will return immediately, either returning + EINTR/ERESTARTSYS if nothing was consumed or returning the amount of data + consumed. + + Notes on recvmsg: (*) If there's a sequence of data messages belonging to a particular call on diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c index 172a4f9747ac..bb1e2caa1720 100644 --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -407,7 +407,7 @@ int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, call->request_size); msg.msg_control = NULL; msg.msg_controllen = 0; - msg.msg_flags = (call->send_pages ? MSG_MORE : 0); + msg.msg_flags = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0); /* We have to change the state *before* sending the last packet as * rxrpc might give us the reply before it returns from sending the @@ -538,15 +538,26 @@ static void afs_deliver_to_call(struct afs_call *call) */ static int afs_wait_for_call_to_complete(struct afs_call *call) { + signed long rtt2, timeout; int ret; + u64 rtt; + u32 life, last_life; DECLARE_WAITQUEUE(myself, current); _enter(""); + rtt = rxrpc_kernel_get_rtt(afs_socket, call->rxcall); + rtt2 = nsecs_to_jiffies64(rtt) * 2; + if (rtt2 < 2) + rtt2 = 2; + + timeout = rtt2; + last_life = rxrpc_kernel_check_life(afs_socket, call->rxcall); + add_wait_queue(&call->waitq, &myself); for (;;) { - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(TASK_UNINTERRUPTIBLE); /* deliver any messages that are in the queue */ if (call->state < AFS_CALL_COMPLETE && call->need_attention) { @@ -556,10 +567,20 @@ static int afs_wait_for_call_to_complete(struct afs_call *call) continue; } - if (call->state == AFS_CALL_COMPLETE || - signal_pending(current)) + if (call->state == AFS_CALL_COMPLETE) break; - schedule(); + + life = rxrpc_kernel_check_life(afs_socket, call->rxcall); + if (timeout == 0 && + life == last_life && signal_pending(current)) + break; + + if (life != last_life) { + timeout = rtt2; + last_life = life; + } + + timeout = schedule_timeout(timeout); } remove_wait_queue(&call->waitq, &myself); diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c index 9ea6f972767e..2d9edc656ca3 100644 --- a/net/rxrpc/sendmsg.c +++ b/net/rxrpc/sendmsg.c @@ -37,13 +37,87 @@ struct rxrpc_send_params { bool upgrade; /* If the connection is upgradeable */ }; +/* + * Wait for space to appear in the Tx queue or a signal to occur. + */ +static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx, + struct rxrpc_call *call, + long *timeo) +{ + for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + if (call->tx_top - call->tx_hard_ack < + min_t(unsigned int, call->tx_winsize, + call->cong_cwnd + call->cong_extra)) + return 0; + + if (call->state >= RXRPC_CALL_COMPLETE) + return call->error; + + if (signal_pending(current)) + return sock_intr_errno(*timeo); + + trace_rxrpc_transmit(call, rxrpc_transmit_wait); + mutex_unlock(&call->user_mutex); + *timeo = schedule_timeout(*timeo); + if (mutex_lock_interruptible(&call->user_mutex) < 0) + return sock_intr_errno(*timeo); + } +} + +/* + * Wait for space to appear in the Tx queue uninterruptibly, but with + * a timeout of 2*RTT if no progress was made and a signal occurred. + */ +static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx, + struct rxrpc_call *call) +{ + rxrpc_seq_t tx_start, tx_win; + signed long rtt2, timeout; + u64 rtt; + + rtt = READ_ONCE(call->peer->rtt); + rtt2 = nsecs_to_jiffies64(rtt) * 2; + if (rtt2 < 1) + rtt2 = 1; + + timeout = rtt2; + tx_start = READ_ONCE(call->tx_hard_ack); + + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + + tx_win = READ_ONCE(call->tx_hard_ack); + if (call->tx_top - tx_win < + min_t(unsigned int, call->tx_winsize, + call->cong_cwnd + call->cong_extra)) + return 0; + + if (call->state >= RXRPC_CALL_COMPLETE) + return call->error; + + if (timeout == 0 && + tx_win == tx_start && signal_pending(current)) + return -EINTR; + + if (tx_win != tx_start) { + timeout = rtt2; + tx_start = tx_win; + } + + trace_rxrpc_transmit(call, rxrpc_transmit_wait); + timeout = schedule_timeout(timeout); + } +} + /* * wait for space to appear in the transmit/ACK window * - caller holds the socket locked */ static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx, struct rxrpc_call *call, - long *timeo) + long *timeo, + bool waitall) { DECLARE_WAITQUEUE(myself, current); int ret; @@ -53,30 +127,10 @@ static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx, add_wait_queue(&call->waitq, &myself); - for (;;) { - set_current_state(TASK_INTERRUPTIBLE); - ret = 0; - if (call->tx_top - call->tx_hard_ack < - min_t(unsigned int, call->tx_winsize, - call->cong_cwnd + call->cong_extra)) - break; - if (call->state >= RXRPC_CALL_COMPLETE) { - ret = call->error; - break; - } - if (signal_pending(current)) { - ret = sock_intr_errno(*timeo); - break; - } - - trace_rxrpc_transmit(call, rxrpc_transmit_wait); - mutex_unlock(&call->user_mutex); - *timeo = schedule_timeout(*timeo); - if (mutex_lock_interruptible(&call->user_mutex) < 0) { - ret = sock_intr_errno(*timeo); - break; - } - } + if (waitall) + ret = rxrpc_wait_for_tx_window_nonintr(rx, call); + else + ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo); remove_wait_queue(&call->waitq, &myself); set_current_state(TASK_RUNNING); @@ -254,7 +308,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx, if (msg->msg_flags & MSG_DONTWAIT) goto maybe_error; ret = rxrpc_wait_for_tx_window(rx, call, - &timeo); + &timeo, + msg->msg_flags & MSG_WAITALL); if (ret < 0) goto maybe_error; }