sunrpc: use better NUMA affinities

Use NUMA aware allocations to reduce latencies and increase throughput.

sunrpc kthreads can use kthread_create_on_node() if pool_mode is
"percpu" or "pernode", and svc_prepare_thread()/svc_init_buffer() can
also take into account NUMA node affinity for memory allocations.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: "J. Bruce Fields" <bfields@fieldses.org>
CC: Neil Brown <neilb@suse.de>
CC: David Miller <davem@davemloft.net>
Reviewed-by: Greg Banks <gnb@fastmail.fm>
[bfields@redhat.com: fix up caller nfs41_callback_up]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index abfff9d..c061b9a 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -282,7 +282,7 @@
 	/*
 	 * Create the kernel thread and wait for it to start.
 	 */
-	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
+	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
 	if (IS_ERR(nlmsvc_rqst)) {
 		error = PTR_ERR(nlmsvc_rqst);
 		nlmsvc_rqst = NULL;