diff options
Diffstat (limited to 'net/rxrpc/call_event.c')
-rw-r--r-- | net/rxrpc/call_event.c | 217 |
1 files changed, 141 insertions, 76 deletions
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c index 6143204..4f00476 100644 --- a/net/rxrpc/call_event.c +++ b/net/rxrpc/call_event.c @@ -24,28 +24,56 @@ /* * Set the timer */ -static void rxrpc_set_timer(struct rxrpc_call *call) +void rxrpc_set_timer(struct rxrpc_call *call, enum rxrpc_timer_trace why, + ktime_t now) { - unsigned long t, now = jiffies; + unsigned long t_j, now_j = jiffies; + ktime_t t; + bool queue = false; - _enter("{%ld,%ld,%ld:%ld}", - call->ack_at - now, call->resend_at - now, call->expire_at - now, - call->timer.expires - now); - read_lock_bh(&call->state_lock); if (call->state < RXRPC_CALL_COMPLETE) { - t = call->ack_at; - if (time_before(call->resend_at, t)) + t = call->expire_at; + if (!ktime_after(t, now)) + goto out; + + if (!ktime_after(call->resend_at, now)) { + call->resend_at = call->expire_at; + if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events)) + queue = true; + } else if (ktime_before(call->resend_at, t)) { t = call->resend_at; - if (time_before(call->expire_at, t)) - t = call->expire_at; - if (!timer_pending(&call->timer) || - time_before(t, call->timer.expires)) { - _debug("set timer %ld", t - now); - mod_timer(&call->timer, t); } + + if (!ktime_after(call->ack_at, now)) { + call->ack_at = call->expire_at; + if (!test_and_set_bit(RXRPC_CALL_EV_ACK, &call->events)) + queue = true; + } else if (ktime_before(call->ack_at, t)) { + t = call->ack_at; + } + + t_j = nsecs_to_jiffies(ktime_to_ns(ktime_sub(t, now))); + t_j += jiffies; + + /* We have to make sure that the calculated jiffies value falls + * at or after the nsec value, or we may loop ceaselessly + * because the timer times out, but we haven't reached the nsec + * timeout yet. + */ + t_j++; + + if (call->timer.expires != t_j || !timer_pending(&call->timer)) { + mod_timer(&call->timer, t_j); + trace_rxrpc_timer(call, why, now, now_j); + } + + if (queue) + rxrpc_queue_call(call); } + +out: read_unlock_bh(&call->state_lock); } @@ -54,14 +82,14 @@ static void rxrpc_set_timer(struct rxrpc_call *call) */ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, u16 skew, u32 serial, bool immediate, - bool background) + bool background, + enum rxrpc_propose_ack_trace why) { - unsigned long now, ack_at, expiry = rxrpc_soft_ack_delay; + enum rxrpc_propose_ack_outcome outcome = rxrpc_propose_ack_use; + unsigned int expiry = rxrpc_soft_ack_delay; + ktime_t now, ack_at; s8 prior = rxrpc_ack_priority[ack_reason]; - _enter("{%d},%s,%%%x,%u", - call->debug_id, rxrpc_acks(ack_reason), serial, immediate); - /* Update DELAY, IDLE, REQUESTED and PING_RESPONSE ACK serial * numbers, but we don't alter the timeout. */ @@ -70,15 +98,18 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, call->ackr_reason, rxrpc_ack_priority[call->ackr_reason]); if (ack_reason == call->ackr_reason) { if (RXRPC_ACK_UPDATEABLE & (1 << ack_reason)) { + outcome = rxrpc_propose_ack_update; call->ackr_serial = serial; call->ackr_skew = skew; } if (!immediate) - return; + goto trace; } else if (prior > rxrpc_ack_priority[call->ackr_reason]) { call->ackr_reason = ack_reason; call->ackr_serial = serial; call->ackr_skew = skew; + } else { + outcome = rxrpc_propose_ack_subsume; } switch (ack_reason) { @@ -94,6 +125,7 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, expiry = rxrpc_soft_ack_delay; break; + case RXRPC_ACK_PING: case RXRPC_ACK_IDLE: if (rxrpc_idle_ack_delay < expiry) expiry = rxrpc_idle_ack_delay; @@ -104,7 +136,6 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, break; } - now = jiffies; if (test_bit(RXRPC_CALL_EV_ACK, &call->events)) { _debug("already scheduled"); } else if (immediate || expiry == 0) { @@ -113,42 +144,56 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, background) rxrpc_queue_call(call); } else { - ack_at = now + expiry; - _debug("deferred ACK %ld < %ld", expiry, call->ack_at - now); - if (time_before(ack_at, call->ack_at)) { + now = ktime_get_real(); + ack_at = ktime_add_ms(now, expiry); + if (ktime_before(ack_at, call->ack_at)) { call->ack_at = ack_at; - rxrpc_set_timer(call); + rxrpc_set_timer(call, rxrpc_timer_set_for_ack, now); } } + +trace: + trace_rxrpc_propose_ack(call, why, ack_reason, serial, immediate, + background, outcome); } /* * propose an ACK be sent, locking the call structure */ void rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, - u16 skew, u32 serial, bool immediate, bool background) + u16 skew, u32 serial, bool immediate, bool background, + enum rxrpc_propose_ack_trace why) { spin_lock_bh(&call->lock); __rxrpc_propose_ACK(call, ack_reason, skew, serial, - immediate, background); + immediate, background, why); spin_unlock_bh(&call->lock); } /* + * Handle congestion being detected by the retransmit timeout. + */ +static void rxrpc_congestion_timeout(struct rxrpc_call *call) +{ + set_bit(RXRPC_CALL_RETRANS_TIMEOUT, &call->flags); +} + +/* * Perform retransmission of NAK'd and unack'd packets. */ -static void rxrpc_resend(struct rxrpc_call *call) +static void rxrpc_resend(struct rxrpc_call *call, ktime_t now) { - struct rxrpc_wire_header *whdr; struct rxrpc_skb_priv *sp; struct sk_buff *skb; rxrpc_seq_t cursor, seq, top; - unsigned long resend_at, now; + ktime_t max_age, oldest, ack_ts; int ix; - u8 annotation; + u8 annotation, anno_type, retrans = 0, unacked = 0; _enter("{%d,%d}", call->tx_hard_ack, call->tx_top); + max_age = ktime_sub_ms(now, rxrpc_resend_timeout); + spin_lock_bh(&call->lock); cursor = call->tx_hard_ack; @@ -161,68 +206,82 @@ static void rxrpc_resend(struct rxrpc_call *call) * the packets in the Tx buffer we're going to resend and what the new * resend timeout will be. */ - now = jiffies; - resend_at = now + rxrpc_resend_timeout; - seq = cursor + 1; - do { + oldest = now; + for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; - if (annotation == RXRPC_TX_ANNO_ACK) + anno_type = annotation & RXRPC_TX_ANNO_MASK; + annotation &= ~RXRPC_TX_ANNO_MASK; + if (anno_type == RXRPC_TX_ANNO_ACK) continue; skb = call->rxtx_buffer[ix]; - rxrpc_see_skb(skb); + rxrpc_see_skb(skb, rxrpc_skb_tx_seen); sp = rxrpc_skb(skb); - if (annotation == RXRPC_TX_ANNO_UNACK) { - if (time_after(sp->resend_at, now)) { - if (time_before(sp->resend_at, resend_at)) - resend_at = sp->resend_at; + if (anno_type == RXRPC_TX_ANNO_UNACK) { + if (ktime_after(skb->tstamp, max_age)) { + if (ktime_before(skb->tstamp, oldest)) + oldest = skb->tstamp; continue; } + if (!(annotation & RXRPC_TX_ANNO_RESENT)) + unacked++; } /* Okay, we need to retransmit a packet. */ - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS; - seq++; - } while (before_eq(seq, top)); + call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation; + retrans++; + trace_rxrpc_retransmit(call, seq, annotation | anno_type, + ktime_to_ns(ktime_sub(skb->tstamp, max_age))); + } + + call->resend_at = ktime_add_ms(oldest, rxrpc_resend_timeout); - call->resend_at = resend_at; + if (unacked) + rxrpc_congestion_timeout(call); + + /* If there was nothing that needed retransmission then it's likely + * that an ACK got lost somewhere. Send a ping to find out instead of + * retransmitting data. + */ + if (!retrans) { + rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now); + spin_unlock_bh(&call->lock); + ack_ts = ktime_sub(now, call->acks_latest_ts); + if (ktime_to_ns(ack_ts) < call->peer->rtt) + goto out; + rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false, + rxrpc_propose_ack_ping_for_lost_ack); + rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK); + goto out; + } /* Now go through the Tx window and perform the retransmissions. We * have to drop the lock for each send. If an ACK comes in whilst the * lock is dropped, it may clear some of the retransmission markers for * packets that it soft-ACKs. */ - seq = cursor + 1; - do { + for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; - if (annotation != RXRPC_TX_ANNO_RETRANS) + anno_type = annotation & RXRPC_TX_ANNO_MASK; + if (anno_type != RXRPC_TX_ANNO_RETRANS) continue; skb = call->rxtx_buffer[ix]; - rxrpc_get_skb(skb); + rxrpc_get_skb(skb, rxrpc_skb_tx_got); spin_unlock_bh(&call->lock); - sp = rxrpc_skb(skb); - - /* Each Tx packet needs a new serial number */ - sp->hdr.serial = atomic_inc_return(&call->conn->serial); - whdr = (struct rxrpc_wire_header *)skb->head; - whdr->serial = htonl(sp->hdr.serial); - - if (rxrpc_send_data_packet(call->conn, skb) < 0) { - call->resend_at = now + 2; - rxrpc_free_skb(skb); + if (rxrpc_send_data_packet(call, skb, true) < 0) { + rxrpc_free_skb(skb, rxrpc_skb_tx_freed); return; } if (rxrpc_is_client_call(call)) rxrpc_expose_client_call(call); - sp->resend_at = now + rxrpc_resend_timeout; - rxrpc_free_skb(skb); + rxrpc_free_skb(skb, rxrpc_skb_tx_freed); spin_lock_bh(&call->lock); /* We need to clear the retransmit state, but there are two @@ -230,18 +289,25 @@ static void rxrpc_resend(struct rxrpc_call *call) * received and the packet might have been hard-ACK'd (in which * case it will no longer be in the buffer). */ - if (after(seq, call->tx_hard_ack) && - (call->rxtx_annotations[ix] == RXRPC_TX_ANNO_RETRANS || - call->rxtx_annotations[ix] == RXRPC_TX_ANNO_NAK)) - call->rxtx_annotations[ix] = RXRPC_TX_ANNO_UNACK; + if (after(seq, call->tx_hard_ack)) { + annotation = call->rxtx_annotations[ix]; + anno_type = annotation & RXRPC_TX_ANNO_MASK; + if (anno_type == RXRPC_TX_ANNO_RETRANS || + anno_type == RXRPC_TX_ANNO_NAK) { + annotation &= ~RXRPC_TX_ANNO_MASK; + annotation |= RXRPC_TX_ANNO_UNACK; + } + annotation |= RXRPC_TX_ANNO_RESENT; + call->rxtx_annotations[ix] = annotation; + } if (after(call->tx_hard_ack, seq)) seq = call->tx_hard_ack; - seq++; - } while (before_eq(seq, top)); + } out_unlock: spin_unlock_bh(&call->lock); +out: _leave(""); } @@ -252,7 +318,7 @@ void rxrpc_process_call(struct work_struct *work) { struct rxrpc_call *call = container_of(work, struct rxrpc_call, processor); - unsigned long now; + ktime_t now; rxrpc_see_call(call); @@ -271,14 +337,14 @@ recheck_state: goto out_put; } - now = jiffies; - if (time_after_eq(now, call->expire_at)) { + now = ktime_get_real(); + if (ktime_before(call->expire_at, now)) { rxrpc_abort_call("EXP", call, 0, RX_CALL_TIMEOUT, ETIME); set_bit(RXRPC_CALL_EV_ABORT, &call->events); + goto recheck_state; } - if (test_and_clear_bit(RXRPC_CALL_EV_ACK, &call->events) || - time_after_eq(now, call->ack_at)) { + if (test_and_clear_bit(RXRPC_CALL_EV_ACK, &call->events)) { call->ack_at = call->expire_at; if (call->ackr_reason) { rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK); @@ -286,13 +352,12 @@ recheck_state: } } - if (test_and_clear_bit(RXRPC_CALL_EV_RESEND, &call->events) || - time_after_eq(now, call->resend_at)) { - rxrpc_resend(call); + if (test_and_clear_bit(RXRPC_CALL_EV_RESEND, &call->events)) { + rxrpc_resend(call, now); goto recheck_state; } - rxrpc_set_timer(call); + rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now); /* other events may have been raised since we started checking */ if (call->events && call->state < RXRPC_CALL_COMPLETE) { |