From: Stephen Hemminger <stephen@networkplumber.org>
Date: Wed, 6 Sep 2017 13:53:06 -0700
Patch-mainline: v4.14-rc1
Subject: hv_netvsc: avoid unnecessary wakeups on subchannel creation
Git-commit: 8f2bb1de73344dbedd4195016b782bee7bf3598f
References: fate#323887

Only need to wakeup the initiator after all sub-channels
are opened.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Olaf Hering <ohering@suse.de>
---
 drivers/net/hyperv/rndis_filter.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1048,8 +1048,8 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
 	else
 		netdev_notice(ndev, "sub channel open failed: %d\n", ret);
 
-	atomic_inc(&nvscdev->open_chn);
-	wake_up(&nvscdev->subchan_open);
+	if (atomic_inc_return(&nvscdev->open_chn) == nvscdev->num_chn)
+		wake_up(&nvscdev->subchan_open);
 }
 
 /* Open sub-channels after completing the handling of the device probe.