[PATCH v6 net-next 2/5] net: mscc: ocelot: remove unnecessary stat reading from ethtool

[Colin Foster <colin.foster@in-advantage.com>]

The ocelot_update_stats function only needs to read from one port, yet it
was updating the stats for all ports. Update to only read the stats that
are necessary.

Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
---
 drivers/net/ethernet/mscc/ocelot.c | 33 +++++++++++++++---------------
 1 file changed, 16 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 6933dff1dd37..ab36732e7d3f 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1738,27 +1738,24 @@ void ocelot_get_strings(struct ocelot *ocelot, int port, u32 sset, u8 *data)
 EXPORT_SYMBOL(ocelot_get_strings);
 
 /* Caller must hold &ocelot->stats_lock */
-static void ocelot_update_stats(struct ocelot *ocelot)
+static void ocelot_update_stats_for_port(struct ocelot *ocelot, int port)
 {
-	int i, j;
+	int j;
 
-	for (i = 0; i < ocelot->num_phys_ports; i++) {
-		/* Configure the port to read the stats from */
-		ocelot_write(ocelot, SYS_STAT_CFG_STAT_VIEW(i), SYS_STAT_CFG);
+	/* Configure the port to read the stats from */
+	ocelot_write(ocelot, SYS_STAT_CFG_STAT_VIEW(port), SYS_STAT_CFG);
 
-		for (j = 0; j < ocelot->num_stats; j++) {
-			u32 val;
-			unsigned int idx = i * ocelot->num_stats + j;
+	for (j = 0; j < ocelot->num_stats; j++) {
+		u32 val;
+		unsigned int idx = port * ocelot->num_stats + j;
 
-			val = ocelot_read_rix(ocelot, SYS_COUNT_RX_OCTETS,
-					      ocelot->stats_layout[j].offset);
+		val = ocelot_read_rix(ocelot, SYS_COUNT_RX_OCTETS,
+				      ocelot->stats_layout[j].offset);
 
-			if (val < (ocelot->stats[idx] & U32_MAX))
-				ocelot->stats[idx] += (u64)1 << 32;
+		if (val < (ocelot->stats[idx] & U32_MAX))
+			ocelot->stats[idx] += (u64)1 << 32;
 
-			ocelot->stats[idx] = (ocelot->stats[idx] &
-					      ~(u64)U32_MAX) + val;
-		}
+		ocelot->stats[idx] = (ocelot->stats[idx] & ~(u64)U32_MAX) + val;
 	}
 }
 
@@ -1767,9 +1764,11 @@ static void ocelot_check_stats_work(struct work_struct *work)
 	struct delayed_work *del_work = to_delayed_work(work);
 	struct ocelot *ocelot = container_of(del_work, struct ocelot,
 					     stats_work);
+	int i;
 
 	mutex_lock(&ocelot->stats_lock);
-	ocelot_update_stats(ocelot);
+	for (i = 0; i < ocelot->num_phys_ports; i++)
+		ocelot_update_stats_for_port(ocelot, i);
 	mutex_unlock(&ocelot->stats_lock);
 
 	queue_delayed_work(ocelot->stats_queue, &ocelot->stats_work,
@@ -1783,7 +1782,7 @@ void ocelot_get_ethtool_stats(struct ocelot *ocelot, int port, u64 *data)
 	mutex_lock(&ocelot->stats_lock);
 
 	/* check and update now */
-	ocelot_update_stats(ocelot);
+	ocelot_update_stats_for_port(ocelot, port);
 
 	/* Copy all counters */
 	for (i = 0; i < ocelot->num_stats; i++)
-- 
2.25.1