Subject: [PATCH net-next,v2,2/2] net: update netdev_rx_csum_fault() print dump only once

From: Tanner Love <[email-masked]>
Date: Wed, 26 May 2021 19:13:36 -0400

From: Tanner Love <[email-masked]>

Printing this stack dump multiple times does not provide additional
useful information, and consumes time in the data path. Printing once
is sufficient.

Signed-off-by: Tanner Love <[email-masked]>
Acked-by: Eric Dumazet <[email-masked]>
Acked-by: Mahesh Bandewar <[email-masked]>
---
 net/core/dev.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index febb23708184..af2d109b7266 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -148,6 +148,7 @@
 #include <net/devlink.h>
 #include <linux/pm_runtime.h>
 #include <linux/prandom.h>
+#include <linux/once_lite.h>
 
 #include "net-sysfs.h"
 
@@ -3487,13 +3488,16 @@ EXPORT_SYMBOL(__skb_gso_segment);
 
 /* Take action when hardware reception checksum errors are detected. */
 #ifdef CONFIG_BUG
+static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
+{
+	pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
+	skb_dump(KERN_ERR, skb, true);
+	dump_stack();
+}
+
 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 {
-	if (net_ratelimit()) {
-		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
-		skb_dump(KERN_ERR, skb, true);
-		dump_stack();
-	}
+	DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb);
 }
 EXPORT_SYMBOL(netdev_rx_csum_fault);
 #endif
-- 
2.32.0.rc0.204.g9fa02ecfa5-goog