From: lw@cn.fujitsu.com (Li Wei)
To: kernelnewbies@lists.kernelnewbies.org
Subject: Regarding skb and skb_frags
Date: Tue, 13 May 2014 11:04:32 +0800 [thread overview]
Message-ID: <53718BC0.90108@cn.fujitsu.com> (raw)
In-Reply-To: <CA+aCy1EhbKOxj9sdkEjdBWO=3TZE+gUqx6dROMvnSPfkW+hFoA@mail.gmail.com>
On 05/01/2014 06:42 PM, Pranay Srivastava wrote:
> I was going through a function
>
> dev_alloc_skb
>
> and it seems that the skb_frags are created only if the data length
> passed is > PAGE_SIZE.
>
> My question is that an Ethernet frame won't be bigger than 1500 bytes
> [correct?] so there never will be skb_frags for Ethernet frames.
No, you should consider TSO and GSO things.
Thanks
> However I've seen skb_frags appeared when sending large data.
>
> I'm not sure how to understand this. Does the driver pokes IP header
> to check how many fragments would be coming and decides (on the rcv
> side) how much to pass in dev_alloc_skb ?
>
> Thanks
>
prev parent reply other threads:[~2014-05-13 3:04 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-01 10:42 Regarding skb and skb_frags Pranay Srivastava
2014-05-01 13:59 ` Valdis.Kletnieks at vt.edu
2014-05-01 14:09 ` Pranay Srivastava
2014-05-01 16:20 ` Jeff Haran
2014-05-02 3:16 ` Pranay Srivastava
2014-05-02 16:21 ` Jeff Haran
2014-05-13 3:04 ` Li Wei [this message]
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