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From: Greg Kurz <gkurz@linux.vnet.ibm.com>
To: Catalin Vasile <catalinvasile92@gmail.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [vhost-net] handle_tx: extract data from vq when !zcopy_used
Date: Fri, 10 Apr 2015 17:14:34 +0200	[thread overview]
Message-ID: <20150410171434.20f0b91f@bahia.local> (raw)
In-Reply-To: <CAOMf8tonLt2sUi-LYBc_Ytp5xkVOHKmX=Z+V5NXY_Yn68KJBDA@mail.gmail.com>

On Fri, 10 Apr 2015 15:58:33 +0300
Catalin Vasile <catalinvasile92@gmail.com> wrote:

> I'm really confused.
> Where does vhost-net (handle_tx) actually extract data from vq when zero
> copy is not used?
> I just see it popping a vq element, but not actually copying anything from
> there.

vhost-net just passes the pointers to the socket, whether zero copy is used
or not:

err = sock->ops->sendmsg(NULL, sock, &msg, len);

BTW, I think virtualization@lists.linux-foundation.org would have been more
appropriate since this isn't a about QEMU.

Cheers.

--
Greg

      reply	other threads:[~2015-04-10 15:14 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-10 12:58 [Qemu-devel] [vhost-net] handle_tx: extract data from vq when !zcopy_used Catalin Vasile
2015-04-10 15:14 ` Greg Kurz [this message]

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