From a435ef6b88c987c50ae63be4d885a632b9b5040f Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 9 Mar 2019 00:29:58 +0000 Subject: [PATCH] rxrpc: Fix client call queueing, waiting for channel BugLink: https://bugs.launchpad.net/bugs/1821074 [ Upstream commit 69ffaebb90369ce08657b5aea4896777b9d6e8fc ] rxrpc_get_client_conn() adds a new call to the front of the waiting_calls queue if the connection it's going to use already exists. This is bad as it allows calls to get starved out. Fix this by adding to the tail instead. Also change the other enqueue point in the same function to put it on the front (ie. when we have a new connection). This makes the point that in the case of a new connection the new call goes at the front (though it doesn't actually matter since the queue should be unoccupied). Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects") Signed-off-by: David Howells Reviewed-by: Marc Dionne Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Seth Forshee --- net/rxrpc/conn_client.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c index b2adfa825363..5cf6d9f4761d 100644 --- a/net/rxrpc/conn_client.c +++ b/net/rxrpc/conn_client.c @@ -353,7 +353,7 @@ static int rxrpc_get_client_conn(struct rxrpc_sock *rx, * normally have to take channel_lock but we do this before anyone else * can see the connection. */ - list_add_tail(&call->chan_wait_link, &candidate->waiting_calls); + list_add(&call->chan_wait_link, &candidate->waiting_calls); if (cp->exclusive) { call->conn = candidate; @@ -432,7 +432,7 @@ found_extant_conn: call->conn = conn; call->security_ix = conn->security_ix; call->service_id = conn->service_id; - list_add(&call->chan_wait_link, &conn->waiting_calls); + list_add_tail(&call->chan_wait_link, &conn->waiting_calls); spin_unlock(&conn->channel_lock); _leave(" = 0 [extant %d]", conn->debug_id); return 0; -- 2.39.5