net: mscc: ocelot: remove unnecessary stat reading from ethtool

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>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mscc/ocelot.c

@@ -1746,17 +1746,16 @@ 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_port_update_stats(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);
+	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;
+		unsigned int idx = port * ocelot->num_stats + j;
 
 		val = ocelot_read_rix(ocelot, SYS_COUNT_RX_OCTETS,
 				      ocelot->stats_layout[j].offset);
@@ -1764,9 +1763,7 @@ static void ocelot_update_stats(struct ocelot *ocelot)
 		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;
 	}
 }
 
@@ -1775,9 +1772,11 @@ 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_port_update_stats(ocelot, i);
 	mutex_unlock(&ocelot->stats_lock);
 
 	queue_delayed_work(ocelot->stats_queue, &ocelot->stats_work,
@@ -1791,7 +1790,7 @@ 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_port_update_stats(ocelot, port);
 
 	/* Copy all counters */
 	for (i = 0; i < ocelot->num_stats; i++)