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Date: Mon, 29 Jul 2024 19:15:59 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Justin Lai <justinlai0215@realtek.com>
Cc: <davem@davemloft.net>, <edumazet@google.com>, <pabeni@redhat.com>,
 <linux-kernel@vger.kernel.org>, <netdev@vger.kernel.org>, <andrew@lunn.ch>,
 <jiri@resnulli.us>, <horms@kernel.org>, <rkannoth@marvell.com>,
 <jdamato@fastly.com>, <pkshih@realtek.com>, <larry.chiu@realtek.com>
Subject: Re: [PATCH net-next v25 02/13] rtase: Implement the .ndo_open
 function
Message-ID: <20240729191559.1683ec63@kernel.org>
In-Reply-To: <20240729062121.335080-3-justinlai0215@realtek.com>
References: <20240729062121.335080-1-justinlai0215@realtek.com>
	<20240729062121.335080-3-justinlai0215@realtek.com>
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On Mon, 29 Jul 2024 14:21:10 +0800 Justin Lai wrote:
> +	page = page_pool_dev_alloc_pages(tp->page_pool);
> +	if (!page) {
> +		netdev_err(tp->dev, "failed to alloc page\n");
> +		goto err_out;
> +	}
> +
> +	buf_addr = page_address(page);
> +	mapping = page_pool_get_dma_addr(page);
> +
> +	skb = build_skb(buf_addr, PAGE_SIZE);

Don't build_skb() before packet was received.

One of the benefits of build_skb() is that the skb is supposed
to be more likely to be still in CPU cache.