xen-netfront: respect user provided max_queues

Originally that parameter was always reset to num_online_cpus during
module initialisation, which renders it useless.

The fix is to only set max_queues to num_online_cpus when user has not
provided a value.

Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Tested-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 32a844056fd43dda647e1c3c6b9983bdfa04d17d)
Signed-off-by: Annie Li <annie.li@oracle.com>

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index e27e6d2ea6d283cc3508579b38e8fb27b8ade035..b9c637a0036b5a8f2df110a27a2aadfc817114e3 100644 (file)
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -2132,8 +2132,11 @@ static int __init netif_init(void)
 
        pr_info("Initialising Xen virtual ethernet driver\n");
 
-       /* Allow as many queues as there are CPUs, by default */
-       xennet_max_queues = num_online_cpus();
+       /* Allow as many queues as there are CPUs if user has not
+        * specified a value.
+        */
+       if (xennet_max_queues == 0)
+               xennet_max_queues = num_online_cpus();
 
        return xenbus_register_frontend(&netfront_driver);
 }