rxrpc: Obtain RTT data by requesting ACKs on DATA packets

[mirror_ubuntu-zesty-kernel.git] / net / rxrpc / call_event.c

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 34ad967f2d818e259a82cb5ee1335a843737dc48..adb2ec61e21f16643ae7caf5533514d1d7d9de5b 100644 (file)
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -142,12 +142,14 @@ static void rxrpc_resend(struct rxrpc_call *call)
        struct rxrpc_skb_priv *sp;
        struct sk_buff *skb;
        rxrpc_seq_t cursor, seq, top;
-       unsigned long resend_at, now;
+       ktime_t now = ktime_get_real(), max_age, oldest, resend_at;
        int ix;
        u8 annotation, anno_type;
 
        _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;
@@ -160,8 +162,7 @@ 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;
+       oldest = now;
        for (seq = cursor + 1; before_eq(seq, top); seq++) {
                ix = seq & RXRPC_RXTX_BUFF_MASK;
                annotation = call->rxtx_annotations[ix];
@@ -175,9 +176,9 @@ static void rxrpc_resend(struct rxrpc_call *call)
                sp = rxrpc_skb(skb);
 
                if (anno_type == 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 (ktime_after(skb->tstamp, max_age)) {
+                               if (ktime_before(skb->tstamp, oldest))
+                                       oldest = skb->tstamp;
                                continue;
                        }
                }
@@ -186,7 +187,8 @@ static void rxrpc_resend(struct rxrpc_call *call)
                call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation;
        }
 
-       call->resend_at = resend_at;
+       resend_at = ktime_sub(ktime_add_ns(oldest, rxrpc_resend_timeout), now);
+       call->resend_at = jiffies + nsecs_to_jiffies(ktime_to_ns(resend_at));
 
        /* 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
@@ -205,15 +207,12 @@ static void rxrpc_resend(struct rxrpc_call *call)
                spin_unlock_bh(&call->lock);
 
                if (rxrpc_send_data_packet(call, skb) < 0) {
-                       call->resend_at = now + 2;
                        rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
                        return;
                }
 
                if (rxrpc_is_client_call(call))
                        rxrpc_expose_client_call(call);
-               sp = rxrpc_skb(skb);
-               sp->resend_at = now + rxrpc_resend_timeout;
 
                rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
                spin_lock_bh(&call->lock);