bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Magnus Karlsson <magnus.karlsson@gmail.com>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: "Magnus Karlsson" <magnus.karlsson@intel.com>,
	"Björn Töpel" <bjorn.topel@intel.com>,
	"Alexei Starovoitov" <ast@kernel.org>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"Network Development" <netdev@vger.kernel.org>,
	"Jonathan Lemon" <jonathan.lemon@gmail.com>,
	"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
	bpf <bpf@vger.kernel.org>
Subject: Re: [PATCH bpf v2] xsk: improve documentation for AF_XDP
Date: Sun, 20 Oct 2019 21:12:01 +0200	[thread overview]
Message-ID: <CAJ8uoz18+4fFP_JMu0kzFehZceATs5aAD8VUMQY2ax-S2=7Pvg@mail.gmail.com> (raw)
In-Reply-To: <20191020172503.qeee2olqxxnynm6v@ast-mbp.dhcp.thefacebook.com>

On Sun, Oct 20, 2019 at 7:25 PM Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
>
> On Sun, Oct 20, 2019 at 10:13:49AM +0200, Magnus Karlsson wrote:
> > On Sat, Oct 19, 2019 at 11:48 AM Alexei Starovoitov
> > <alexei.starovoitov@gmail.com> wrote:
> > >
> > > On Fri, Oct 18, 2019 at 11:33:40AM +0200, Magnus Karlsson wrote:
> > > > +
> > > > +   #include <linux/bpf.h>
> > > > +   #include "bpf_helpers.h"
> > > > +
> > > > +   #define MAX_SOCKS 16
> > > > +
> > > > +   struct {
> > > > +        __uint(type, BPF_MAP_TYPE_XSKMAP);
> > > > +        __uint(max_entries, MAX_SOCKS);
> > > > +        __uint(key_size, sizeof(int));
> > > > +        __uint(value_size, sizeof(int));
> > > > +   } xsks_map SEC(".maps");
> > > > +
> > > > +   struct {
> > > > +        __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
> > > > +        __uint(max_entries, 1);
> > > > +        __type(key, int);
> > > > +        __type(value, unsigned int);
> > > > +   } rr_map SEC(".maps");
> > >
> > > hmm. does xsks_map compile?
> >
> > Yes. Actually, I wrote a new sample to demonstrate this feature and to
> > test the code above. I will send that patch set (contains some small
> > additions to libbpf also to be able to support this) to bpf-next.
> > Though, if I used the __type declarations of the rr_map PERCPU_ARRAY I
> > got this warning: "pr_warning("Error in
> > bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n")", so I had
> > to change it to the type above that is also used for SOCKMAP. Some
> > enablement that is missing for XSKMAP? Have not dug into it.
>
> Ahh. Right. xskmap explicitly prohibits BTF for key/value.
> const struct bpf_map_ops xsk_map_ops = {
>         ...
>         .map_check_btf = map_check_no_btf,
> };
> I guess it's time to add support for it.

Agreed. I will implement that in a separate patch set for bpf-next and
include a patch to update the documentation too in that patch set.

>

      reply	other threads:[~2019-10-20 19:12 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-18  9:33 [PATCH bpf v2] xsk: improve documentation for AF_XDP Magnus Karlsson
2019-10-18 23:27 ` Alexei Starovoitov
2019-10-20  8:13   ` Magnus Karlsson
2019-10-20 17:25     ` Alexei Starovoitov
2019-10-20 19:12       ` Magnus Karlsson [this message]

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='CAJ8uoz18+4fFP_JMu0kzFehZceATs5aAD8VUMQY2ax-S2=7Pvg@mail.gmail.com' \
    --to=magnus.karlsson@gmail.com \
    --cc=alexei.starovoitov@gmail.com \
    --cc=ast@kernel.org \
    --cc=bjorn.topel@intel.com \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=jonathan.lemon@gmail.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=magnus.karlsson@intel.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 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).