From: Toshiaki Makita <toshiaki.makita1@gmail.com>
To: Jesper Dangaard Brouer <brouer@redhat.com>,
Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Cc: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
netdev@vger.kernel.org,
Jakub Kicinski <jakub.kicinski@netronome.com>,
John Fastabend <john.fastabend@gmail.com>
Subject: Re: [PATCH v7 bpf-next 05/10] veth: Handle xdp_frames in xdp napi ring
Date: Thu, 2 Aug 2018 22:17:53 +0900 [thread overview]
Message-ID: <4402804f-bf7b-9ca0-baa9-1415884b0a80@gmail.com> (raw)
In-Reply-To: <20180802134548.2230455b@redhat.com>
On 18/08/02 (木) 20:45, Jesper Dangaard Brouer wrote:
> On Thu, 2 Aug 2018 19:55:09 +0900
> Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> wrote:
>
>> + headroom = frame->data - delta - (void *)frame;
>
> Your calculation of headroom is still adding an assumption that
> xdp_frame is located in the top of data area, that is unnecessary.
>
> The headroom can be calculated as:
>
> headroom = sizeof(struct xdp_frame) + frame->headroom - delta;
Thanks. But I'm not sure I get what you are requesting.
Supposing xdp_frame is not located in the top of data area, what ensures
that additional sizeof(struct xdp_frame) can be used?
Toshiaki Makita
next prev parent reply other threads:[~2018-08-02 15:09 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-02 10:55 [PATCH v7 bpf-next 00/10] veth: Driver XDP Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 01/10] net: Export skb_headers_offset_update Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 02/10] veth: Add driver XDP Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 03/10] veth: Avoid drops by oversized packets when XDP is enabled Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 04/10] xdp: Helper function to clear kernel pointers in xdp_frame Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 05/10] veth: Handle xdp_frames in xdp napi ring Toshiaki Makita
2018-08-02 11:45 ` Jesper Dangaard Brouer
2018-08-02 13:17 ` Toshiaki Makita [this message]
2018-08-02 13:53 ` Jesper Dangaard Brouer
2018-08-02 14:10 ` Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 06/10] veth: Add ndo_xdp_xmit Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 07/10] bpf: Make redirect_info accessible from modules Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 08/10] xdp: Helpers for disabling napi_direct of xdp_return_frame Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 09/10] veth: Add XDP TX and REDIRECT Toshiaki Makita
2018-08-02 10:55 ` [PATCH v7 bpf-next 10/10] veth: Support per queue XDP ring Toshiaki Makita
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=4402804f-bf7b-9ca0-baa9-1415884b0a80@gmail.com \
--to=toshiaki.makita1@gmail.com \
--cc=ast@kernel.org \
--cc=brouer@redhat.com \
--cc=daniel@iogearbox.net \
--cc=jakub.kicinski@netronome.com \
--cc=john.fastabend@gmail.com \
--cc=makita.toshiaki@lab.ntt.co.jp \
--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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox