From: Long Li <longli@microsoft.com>
Date: Fri, 17 Jul 2020 20:18:29 +0000 (-0700)
Subject: bus/vmbus: use SMP memory barrier for signaling read
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=52c9a533b4179e9d16dfdc03410440c39b61e5af;p=dpdk.git

bus/vmbus: use SMP memory barrier for signaling read

rte_smp_mb() uses the same locked ADD as the in-kernel vmbus driver,
and it has slightly performance improvement over rte_mb().

Signed-off-by: Long Li <longli@microsoft.com>
---

diff --git a/drivers/bus/vmbus/vmbus_channel.c b/drivers/bus/vmbus/vmbus_channel.c
index ff2985c257..4f5578e2c6 100644
--- a/drivers/bus/vmbus/vmbus_channel.c
+++ b/drivers/bus/vmbus/vmbus_channel.c
@@ -214,7 +214,7 @@ void rte_vmbus_chan_signal_read(struct vmbus_channel *chan, uint32_t bytes_read)
 		return;
 
 	/* Make sure reading of pending happens after new read index */
-	rte_mb();
+	rte_smp_mb();
 
 	pending_sz = rbr->vbr->pending_send;
 	if (!pending_sz)