blob: 002a0b3ba608096049b5fe4e9b15e9405747ea0c [file] [log] [blame]
From 7952ab380f296e782076410965a976479f252737 Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Thu, 20 Aug 2020 15:13:00 +0100
Subject: [PATCH] rxrpc: Make rxrpc_kernel_get_srtt() indicate validity
commit 1d4adfaf65746203861c72d9d78de349eb97d528 upstream.
Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned
smoothed RTT. If we haven't had any valid samples yet, the SRTT isn't
useful.
Fixes: c410bf01933e ("rxrpc: Fix the excessive initial retransmission timeout")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c
index 02e976ca5732..51ee3dd79700 100644
--- a/fs/afs/fs_probe.c
+++ b/fs/afs/fs_probe.c
@@ -92,8 +92,8 @@ void afs_fileserver_probe_result(struct afs_call *call)
}
}
- rtt_us = rxrpc_kernel_get_srtt(call->net->socket, call->rxcall);
- if (rtt_us < server->probe.rtt) {
+ if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) &&
+ rtt_us < server->probe.rtt) {
server->probe.rtt = rtt_us;
alist->preferred = index;
have_result = true;
diff --git a/fs/afs/vl_probe.c b/fs/afs/vl_probe.c
index e3aa013c2177..081b7e5b13f5 100644
--- a/fs/afs/vl_probe.c
+++ b/fs/afs/vl_probe.c
@@ -92,8 +92,8 @@ void afs_vlserver_probe_result(struct afs_call *call)
}
}
- rtt_us = rxrpc_kernel_get_srtt(call->net->socket, call->rxcall);
- if (rtt_us < server->probe.rtt) {
+ if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) &&
+ rtt_us < server->probe.rtt) {
server->probe.rtt = rtt_us;
alist->preferred = index;
have_result = true;
diff --git a/include/net/af_rxrpc.h b/include/net/af_rxrpc.h
index ab988940bf04..55b980b21f4b 100644
--- a/include/net/af_rxrpc.h
+++ b/include/net/af_rxrpc.h
@@ -59,7 +59,7 @@ bool rxrpc_kernel_abort_call(struct socket *, struct rxrpc_call *,
void rxrpc_kernel_end_call(struct socket *, struct rxrpc_call *);
void rxrpc_kernel_get_peer(struct socket *, struct rxrpc_call *,
struct sockaddr_rxrpc *);
-u32 rxrpc_kernel_get_srtt(struct socket *, struct rxrpc_call *);
+bool rxrpc_kernel_get_srtt(struct socket *, struct rxrpc_call *, u32 *);
int rxrpc_kernel_charge_accept(struct socket *, rxrpc_notify_rx_t,
rxrpc_user_attach_call_t, unsigned long, gfp_t,
unsigned int);
diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c
index efce27802a74..e011594adcd1 100644
--- a/net/rxrpc/peer_object.c
+++ b/net/rxrpc/peer_object.c
@@ -500,11 +500,21 @@ EXPORT_SYMBOL(rxrpc_kernel_get_peer);
* rxrpc_kernel_get_srtt - Get a call's peer smoothed RTT
* @sock: The socket on which the call is in progress.
* @call: The call to query
+ * @_srtt: Where to store the SRTT value.
*
- * Get the call's peer smoothed RTT.
+ * Get the call's peer smoothed RTT in uS.
*/
-u32 rxrpc_kernel_get_srtt(struct socket *sock, struct rxrpc_call *call)
+bool rxrpc_kernel_get_srtt(struct socket *sock, struct rxrpc_call *call,
+ u32 *_srtt)
{
- return call->peer->srtt_us >> 3;
+ struct rxrpc_peer *peer = call->peer;
+
+ if (peer->rtt_count == 0) {
+ *_srtt = 1000000; /* 1S */
+ return false;
+ }
+
+ *_srtt = call->peer->srtt_us >> 3;
+ return true;
}
EXPORT_SYMBOL(rxrpc_kernel_get_srtt);
--
2.27.0