@@ -97,3 +97,4 @@ u32 minmax_running_min(struct minmax *m, u32 win, u32 t, u32 meas)
return minmax_subwin_update(m, win, &val);
}
+EXPORT_SYMBOL(minmax_running_min);
@@ -371,6 +371,8 @@ struct rxrpc_peer {
spinlock_t rtt_input_lock; /* RTT lock for input routine */
ktime_t rtt_last_req; /* Time of last RTT request */
unsigned int rtt_count; /* Number of samples we've got */
+ unsigned int rtt_taken; /* Number of samples taken (wrapping) */
+ struct minmax min_rtt; /* Estimated minimum RTT */
u32 srtt_us; /* smoothed round trip time << 3 in usecs */
u32 mdev_us; /* medium deviation */
@@ -127,16 +127,27 @@ static void rxrpc_set_rto(struct rxrpc_peer *peer)
peer->rto_us = rxrpc_bound_rto(rto);
}
-static void rxrpc_ack_update_rtt(struct rxrpc_peer *peer, long rtt_us)
+static void rxrpc_update_rtt_min(struct rxrpc_peer *peer, ktime_t resp_time, long rtt_us)
+{
+ /* Window size 5mins in approx usec (ipv4.sysctl_tcp_min_rtt_wlen) */
+ u32 wlen_us = 5ULL * NSEC_PER_SEC / 1024;
+
+ minmax_running_min(&peer->min_rtt, wlen_us, resp_time / 1024,
+ (u32)rtt_us ? : jiffies_to_usecs(1));
+}
+
+static void rxrpc_ack_update_rtt(struct rxrpc_peer *peer, ktime_t resp_time, long rtt_us)
{
if (rtt_us < 0)
return;
- //rxrpc_update_rtt_min(peer, rtt_us);
+ /* Update RACK min RTT [RFC8985 6.1 Step 1]. */
+ rxrpc_update_rtt_min(peer, resp_time, rtt_us);
+
rxrpc_rtt_estimator(peer, rtt_us);
rxrpc_set_rto(peer);
- /* RFC6298: only reset backoff on valid RTT measurement. */
+ /* Only reset backoff on valid RTT measurement [RFC6298]. */
peer->backoff = 0;
}
@@ -157,9 +168,10 @@ void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
return;
spin_lock(&peer->rtt_input_lock);
- rxrpc_ack_update_rtt(peer, rtt_us);
+ rxrpc_ack_update_rtt(peer, resp_time, rtt_us);
if (peer->rtt_count < 3)
peer->rtt_count++;
+ peer->rtt_taken++;
spin_unlock(&peer->rtt_input_lock);
trace_rxrpc_rtt_rx(call, why, rtt_slot, send_serial, resp_serial,
Generate rtt_min as this is required by RACK-TLP. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: "David S. Miller" <davem@davemloft.net> cc: Eric Dumazet <edumazet@google.com> cc: Jakub Kicinski <kuba@kernel.org> cc: Paolo Abeni <pabeni@redhat.com> cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org --- lib/win_minmax.c | 1 + net/rxrpc/ar-internal.h | 2 ++ net/rxrpc/rtt.c | 20 ++++++++++++++++---- 3 files changed, 19 insertions(+), 4 deletions(-)