From: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
To: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Lorenzo Bianconi <lorenzo@kernel.org>, bpf <bpf@vger.kernel.org>,
Netdev <netdev@vger.kernel.org>,
David Miller <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
shayagr@amazon.com, "Jubran, Samih" <sameehj@amazon.com>,
John Fastabend <john.fastabend@gmail.com>,
David Ahern <dsahern@kernel.org>,
Jesper Dangaard Brouer <brouer@redhat.com>,
Eelco Chaudron <echaudro@redhat.com>,
Jason Wang <jasowang@redhat.com>,
Saeed Mahameed <saeed@kernel.org>,
Maciej Fijalkowski <maciej.fijalkowski@intel.com>,
"Karlsson, Magnus" <magnus.karlsson@intel.com>,
Tirthendu <tirthendu.sarkar@intel.com>
Subject: Re: [PATCH v9 bpf-next 07/14] net: xdp: add multi-buff support to xdp_build_skb_from_frame
Date: Tue, 29 Jun 2021 20:34:05 +0200 [thread overview]
Message-ID: <YNtnnT8kEgT5KdWF@lore-desk> (raw)
In-Reply-To: <CAKgT0Ue=74BPWFDFYtWEA9DnNj35PgigDZAwCc5N6X=QpKz4GA@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 2284 bytes --]
> On Mon, Jun 14, 2021 at 5:51 AM Lorenzo Bianconi <lorenzo@kernel.org> wrote:
> >
> > Introduce xdp multi-buff support to
> > __xdp_build_skb_from_frame/xdp_build_skb_from_frame
> > utility routines.
> >
> > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> > ---
> > net/core/xdp.c | 13 +++++++++++++
> > 1 file changed, 13 insertions(+)
> >
> > diff --git a/net/core/xdp.c b/net/core/xdp.c
> > index f61c63115c95..71bedf6049a1 100644
> > --- a/net/core/xdp.c
> > +++ b/net/core/xdp.c
> > @@ -582,9 +582,15 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
> > struct sk_buff *skb,
> > struct net_device *dev)
> > {
> > + struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);
> > unsigned int headroom, frame_size;
> > + int i, num_frags = 0;
> > void *hard_start;
> >
> > + /* xdp multi-buff frame */
> > + if (unlikely(xdp_frame_is_mb(xdpf)))
> > + num_frags = sinfo->nr_frags;
> > +
> > /* Part of headroom was reserved to xdpf */
> > headroom = sizeof(*xdpf) + xdpf->headroom;
> >
> > @@ -603,6 +609,13 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
> > if (xdpf->metasize)
> > skb_metadata_set(skb, xdpf->metasize);
> >
> > + for (i = 0; i < num_frags; i++)
> > + skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
> > + skb_frag_page(&sinfo->frags[i]),
> > + skb_frag_off(&sinfo->frags[i]),
> > + skb_frag_size(&sinfo->frags[i]),
> > + xdpf->frame_sz);
> > +
>
> So this is assuming the header frame and all of the frags are using
> the same size. Rather than reading the frags out and then writing them
> back, why not just directly rewrite the nr_frags, add the total size
> to skb->len and skb->data_len, and then update the truesize?
ack, thx. I will look into it.
Regards,
Lorenzo
>
> Actually, I think you might need to store the truesize somewhere in
> addition to the data_len that you were storing in the shared info.
>
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]
next prev parent reply other threads:[~2021-06-29 18:34 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-14 12:49 [PATCH v9 bpf-next 00/14] mvneta: introduce XDP multi-buffer support Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 01/14] net: skbuff: add data_len field to skb_shared_info Lorenzo Bianconi
2021-06-28 19:58 ` Alexander Duyck
2021-06-29 12:44 ` Lorenzo Bianconi
2021-06-29 17:08 ` Jakub Kicinski
2021-06-29 18:18 ` Alexander Duyck
2021-06-29 18:37 ` Jakub Kicinski
2021-06-29 19:11 ` Jesper Dangaard Brouer
2021-06-29 19:18 ` Lorenzo Bianconi
2021-06-29 20:45 ` Alexander Duyck
2021-06-14 12:49 ` [PATCH v9 bpf-next 02/14] xdp: introduce flags field in xdp_buff/xdp_frame Lorenzo Bianconi
2021-06-28 20:14 ` Alexander Duyck
2021-06-29 12:43 ` Lorenzo Bianconi
2021-06-29 13:07 ` Alexander Duyck
2021-06-29 13:25 ` Lorenzo Bianconi
2021-07-05 15:52 ` Lorenzo Bianconi
2021-07-05 21:35 ` Alexander Duyck
2021-07-06 11:53 ` Lorenzo Bianconi
2021-07-06 14:04 ` Alexander Duyck
2021-07-06 17:47 ` Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 03/14] net: mvneta: update mb bit before passing the xdp buffer to eBPF layer Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 04/14] xdp: add multi-buff support to xdp_return_{buff/frame} Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 05/14] net: mvneta: add multi buffer support to XDP_TX Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 06/14] net: mvneta: enable jumbo frames for XDP Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 07/14] net: xdp: add multi-buff support to xdp_build_skb_from_frame Lorenzo Bianconi
2021-06-28 21:05 ` Alexander Duyck
2021-06-29 18:34 ` Lorenzo Bianconi [this message]
2021-06-14 12:49 ` [PATCH v9 bpf-next 08/14] bpf: add multi-buff support to the bpf_xdp_adjust_tail() API Lorenzo Bianconi
2021-06-22 23:37 ` John Fastabend
2021-06-24 9:26 ` Eelco Chaudron
2021-06-24 14:24 ` John Fastabend
2021-06-24 15:16 ` Zvi Effron
2021-06-29 13:19 ` Lorenzo Bianconi
2021-06-29 13:27 ` Toke Høiland-Jørgensen
2021-07-06 21:44 ` Backwards compatibility for XDP multi-buff (was: Re: [PATCH v9 bpf-next 08/14] bpf: add multi-buff support to the bpf_xdp_adjust_tail() API) Toke Høiland-Jørgensen
2021-06-14 12:49 ` [PATCH v9 bpf-next 09/14] bpf: introduce bpf_xdp_get_buff_len helper Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 10/14] bpf: add multi-buffer support to xdp copy helpers Lorenzo Bianconi
2021-06-22 23:49 ` John Fastabend
2021-06-24 9:42 ` Eelco Chaudron
2021-06-24 14:28 ` John Fastabend
2021-06-25 8:25 ` Eelco Chaudron
2021-06-29 13:23 ` Lorenzo Bianconi
2021-07-06 10:15 ` Eelco Chaudron
2021-06-14 12:49 ` [PATCH v9 bpf-next 11/14] bpf: move user_size out of bpf_test_init Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 12/14] bpf: introduce multibuff support to bpf_prog_test_run_xdp() Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 13/14] bpf: test_run: add xdp_shared_info pointer in bpf_test_finish signature Lorenzo Bianconi
2021-06-14 12:49 ` [PATCH v9 bpf-next 14/14] bpf: update xdp_adjust_tail selftest to include multi-buffer Lorenzo Bianconi
2021-06-22 23:18 ` [PATCH v9 bpf-next 00/14] mvneta: introduce XDP multi-buffer support John Fastabend
2021-06-23 3:41 ` David Ahern
2021-06-23 5:48 ` John Fastabend
2021-06-23 14:40 ` David Ahern
2021-06-24 14:22 ` John Fastabend
2021-07-01 7:56 ` Magnus Karlsson
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=YNtnnT8kEgT5KdWF@lore-desk \
--to=lorenzo.bianconi@redhat.com \
--cc=alexander.duyck@gmail.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=brouer@redhat.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=dsahern@kernel.org \
--cc=echaudro@redhat.com \
--cc=jasowang@redhat.com \
--cc=john.fastabend@gmail.com \
--cc=kuba@kernel.org \
--cc=lorenzo@kernel.org \
--cc=maciej.fijalkowski@intel.com \
--cc=magnus.karlsson@intel.com \
--cc=netdev@vger.kernel.org \
--cc=saeed@kernel.org \
--cc=sameehj@amazon.com \
--cc=shayagr@amazon.com \
--cc=tirthendu.sarkar@intel.com \
/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;
as well as URLs for NNTP newsgroup(s).