From: Eric Dumazet <edumazet@google.com>
Date: Wed, 8 Jun 2022 08:46:38 -0700
Subject: devlink: adopt u64_stats_t
Patch-mainline: v6.0-rc1
Git-commit: 958751e0807d5b2316cc4c7c2834ba9a0fe1b9e8
References: jsc#PED-1549

As explained in commit 316580b69d0a ("u64_stats: provide u64_stats_t type")
we should use u64_stats_t and related accessors to avoid load/store tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/core/devlink.c |   28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -8001,8 +8001,8 @@ static int devlink_nl_cmd_health_reporte
 }
 
 struct devlink_stats {
-	u64 rx_bytes;
-	u64 rx_packets;
+	u64_stats_t rx_bytes;
+	u64_stats_t rx_packets;
 	struct u64_stats_sync syncp;
 };
 
@@ -8159,12 +8159,12 @@ static void devlink_trap_stats_read(stru
 		cpu_stats = per_cpu_ptr(trap_stats, i);
 		do {
 			start = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
-			rx_packets = cpu_stats->rx_packets;
-			rx_bytes = cpu_stats->rx_bytes;
+			rx_packets = u64_stats_read(&cpu_stats->rx_packets);
+			rx_bytes = u64_stats_read(&cpu_stats->rx_bytes);
 		} while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, start));
 
-		stats->rx_packets += rx_packets;
-		stats->rx_bytes += rx_bytes;
+		u64_stats_add(&stats->rx_packets, rx_packets);
+		u64_stats_add(&stats->rx_bytes, rx_bytes);
 	}
 }
 
@@ -8182,11 +8182,13 @@ devlink_trap_group_stats_put(struct sk_b
 		return -EMSGSIZE;
 
 	if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_PACKETS,
-			      stats.rx_packets, DEVLINK_ATTR_PAD))
+			      u64_stats_read(&stats.rx_packets),
+			      DEVLINK_ATTR_PAD))
 		goto nla_put_failure;
 
 	if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_BYTES,
-			      stats.rx_bytes, DEVLINK_ATTR_PAD))
+			      u64_stats_read(&stats.rx_bytes),
+			      DEVLINK_ATTR_PAD))
 		goto nla_put_failure;
 
 	nla_nest_end(msg, attr);
@@ -8226,11 +8228,13 @@ static int devlink_trap_stats_put(struct
 		goto nla_put_failure;
 
 	if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_PACKETS,
-			      stats.rx_packets, DEVLINK_ATTR_PAD))
+			      u64_stats_read(&stats.rx_packets),
+			      DEVLINK_ATTR_PAD))
 		goto nla_put_failure;
 
 	if (nla_put_u64_64bit(msg, DEVLINK_ATTR_STATS_RX_BYTES,
-			      stats.rx_bytes, DEVLINK_ATTR_PAD))
+			      u64_stats_read(&stats.rx_bytes),
+			      DEVLINK_ATTR_PAD))
 		goto nla_put_failure;
 
 	nla_nest_end(msg, attr);
@@ -11743,8 +11747,8 @@ devlink_trap_stats_update(struct devlink
 
 	stats = this_cpu_ptr(trap_stats);
 	u64_stats_update_begin(&stats->syncp);
-	stats->rx_bytes += skb_len;
-	stats->rx_packets++;
+	u64_stats_add(&stats->rx_bytes, skb_len);
+	u64_stats_inc(&stats->rx_packets);
 	u64_stats_update_end(&stats->syncp);
 }