From: Andrew Gallatin <gallatin@myri.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jon Mason <mason@myri.com>, David Miller <davem@davemloft.net>,
netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next] myri10ge: fix truesize underestimation
Date: Thu, 20 Oct 2011 17:04:11 -0400 [thread overview]
Message-ID: <4EA08CCB.8030207@myri.com> (raw)
In-Reply-To: <1319144356.2854.36.camel@edumazet-laptop>
On 10/20/11 16:59, Eric Dumazet wrote:
> Le jeudi 20 octobre 2011 à 16:45 -0400, Andrew Gallatin a écrit :
>> On 10/20/11 16:44, Eric Dumazet wrote:
>>> Le jeudi 20 octobre 2011 à 15:33 -0500, Jon Mason a écrit :
>>>> On Thu, Oct 20, 2011 at 3:10 PM, Eric Dumazet<eric.dumazet@gmail.com> wrote:
>>>>> skb->truesize must account for allocated memory, not the used part of
>>>>> it. Doing this work is important to avoid unexpected OOM situations.
>>>>>
>>>>> Signed-off-by: Eric Dumazet<eric.dumazet@gmail.com>
>>>>
>>>> Acked-by: Jon Mason<mason@myri.com>
>>>
>>> Thanks for reviewing Jon !
>>>
>>>
>>
>> Please wait a second.. I think the patch is incorrect.
>>
>> There is already code in myri10ge_rx_skb_build() which
>> attempts to set the truesize. However, it sets it to
>> the used, rather than the allocated size so it is apparently
>> incorrect.
>>
>> I'd prefer we fix that code.
>
> Well, I believe I did exactly that :)
>
> truesize of initial skb is fine.
>
> Then for everay frag added, you must add to skb-truesize the allocated
> memory for this frag.
>
> You add frags of a given size (small or big)
>
> In the end, its truesize += bytes * number_of_frags
>
> (bytes being small_size or big_size)
>
>
OK, I'm feeling foolish. I somehow missed the first hunk
of your patch (some local change made it not apply cleanly, and
I did not notice that).
Yes, your patch is correct. Sorry for the hassle!
Acked-by: Andrew Gallatin <gallatin@myri.com>
next prev parent reply other threads:[~2011-10-20 21:04 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-10-20 20:10 [PATCH net-next] myri10ge: fix truesize underestimation Eric Dumazet
2011-10-20 20:33 ` Jon Mason
2011-10-20 20:44 ` Eric Dumazet
2011-10-20 20:45 ` Andrew Gallatin
2011-10-20 20:59 ` Eric Dumazet
2011-10-20 21:03 ` David Miller
2011-10-20 21:04 ` Andrew Gallatin [this message]
2011-10-20 21:06 ` Eric Dumazet
2011-10-20 21:42 ` David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4EA08CCB.8030207@myri.com \
--to=gallatin@myri.com \
--cc=davem@davemloft.net \
--cc=eric.dumazet@gmail.com \
--cc=mason@myri.com \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.