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Message-ID: <41e4b0e3-ecc0-43ca-a6cd-4a6beb0ceb8f@datenfreihafen.org>
Date: Mon, 3 Jun 2024 11:33:28 +0200
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MIME-Version: 1.0
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Subject: Re: [PATCH] net: mac802154: Fix racy device stats updates by
 DEV_STATS_INC() and DEV_STATS_ADD()
To: Yunshui Jiang <jiangyunshui@kylinos.cn>, linux-kernel@vger.kernel.org,
 netdev@vger.kernel.org, linux-wpan@vger.kernel.org
Cc: alex.aring@gmail.com, miquel.raynal@bootlin.com, davem@davemloft.net
References: <20240531080739.2608969-1-jiangyunshui@kylinos.cn>
Content-Language: en-US
From: Stefan Schmidt <stefan@datenfreihafen.org>
In-Reply-To: <20240531080739.2608969-1-jiangyunshui@kylinos.cn>
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Hello.

On 31.05.24 10:07, Yunshui Jiang wrote:
> mac802154 devices update their dev->stats fields locklessly. Therefore
> these counters should be updated atomically. Adopt SMP safe DEV_STATS_INC()
> and DEV_STATS_ADD() to achieve this.
> 
> Signed-off-by: Yunshui Jiang <jiangyunshui@kylinos.cn>
> ---
>   net/mac802154/tx.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
> index 2a6f1ed763c9..6fbed5bb5c3e 100644
> --- a/net/mac802154/tx.c
> +++ b/net/mac802154/tx.c
> @@ -34,8 +34,8 @@ void ieee802154_xmit_sync_worker(struct work_struct *work)
>   	if (res)
>   		goto err_tx;
>   
> -	dev->stats.tx_packets++;
> -	dev->stats.tx_bytes += skb->len;
> +	DEV_STATS_INC(dev, tx_packets);
> +	DEV_STATS_ADD(dev, tx_bytes, skb->len);
>   
>   	ieee802154_xmit_complete(&local->hw, skb, false);
>   
> @@ -90,8 +90,8 @@ ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
>   		if (ret)
>   			goto err_wake_netif_queue;
>   
> -		dev->stats.tx_packets++;
> -		dev->stats.tx_bytes += len;
> +		DEV_STATS_INC(dev, tx_packets);
> +		DEV_STATS_ADD(dev, tx_bytes, len);
>   	} else {
>   		local->tx_skb = skb;
>   		queue_work(local->workqueue, &local->sync_tx_work);

This patch has been applied to the wpan tree and will be
part of the next pull request to net. Thanks!

regards
Stefan Schmidt