[dpdk-stable] patch 'net/sfc: request MAC stats upload immediately on port start' has been queued to stable release 17.05.2

[Yuanhan Liu]

Hi,

FYI, your patch has been queued to stable release 17.05.2

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 08/24/17. So please
shout if anyone has objections.

Thanks.

	--yliu

---
>From f68f6ccbede3f6b683b9d46a4f61ead29ff15241 Mon Sep 17 00:00:00 2001
From: Ivan Malov <ivan.malov at oktetlabs.ru>
Date: Sat, 8 Jul 2017 16:16:55 +0100
Subject: [PATCH] net/sfc: request MAC stats upload immediately on port start

[ upstream commit 3b257f7e6c0fb5daa7b5f3b08e992effb45341e9 ]

If MAC stats refresh is arranged to be done by periodic DMA,
the first DMA transaction is unlikely to occur right on the
port start; if the user tries to get stats right after port
start and before the transaction occurs, bogus figures will
be collected; a one-off stats upload on port start is a fix

Fixes: 1caab2f1e684 ("net/sfc: add basic statistics")

Signed-off-by: Ivan Malov <ivan.malov at oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko at solarflare.com>
---
 drivers/net/sfc/sfc_port.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/net/sfc/sfc_port.c b/drivers/net/sfc/sfc_port.c
index ee96bcd..87affc9 100644
--- a/drivers/net/sfc/sfc_port.c
+++ b/drivers/net/sfc/sfc_port.c
@@ -242,6 +242,18 @@ sfc_port_start(struct sfc_adapter *sa)
 		}
 	}
 
+	if ((port->mac_stats_update_period_ms != 0) &&
+	    port->mac_stats_periodic_dma_supported) {
+		/*
+		 * Request an explicit MAC stats upload immediately to
+		 * preclude bogus figures readback if the user decides
+		 * to read stats before periodic DMA is really started
+		 */
+		rc = efx_mac_stats_upload(sa->nic, &port->mac_stats_dma_mem);
+		if (rc != 0)
+			goto fail_mac_stats_upload;
+	}
+
 	sfc_log_init(sa, "disable MAC drain");
 	rc = efx_mac_drain(sa->nic, B_FALSE);
 	if (rc != 0)
@@ -262,6 +274,7 @@ fail_mac_drain:
 	(void)efx_mac_stats_periodic(sa->nic, &port->mac_stats_dma_mem,
 				     0, B_FALSE);
 
+fail_mac_stats_upload:
 fail_mac_stats_periodic:
 fail_mcast_address_list_set:
 fail_mac_filter_set:
-- 
2.7.4