From: Paul Chaignon <paul.chaignon@gmail.com>
To: Eduard Zingerman <eddyz87@gmail.com>
Cc: bpf@vger.kernel.org, ast@kernel.org, andrii@kernel.org,
daniel@iogearbox.net, martin.lau@linux.dev, kernel-team@fb.com,
yonghong.song@linux.dev,
Alexei Starovoitov <alexei.starovoitov@gmail.com>
Subject: Re: [PATCH bpf-next v4 09/14] bpf: simplify liveness to use (callsite, depth) keyed func_instances
Date: Mon, 13 Apr 2026 15:31:04 +0200 [thread overview]
Message-ID: <adzwGJXuXcVbF5H1@Tunnel> (raw)
In-Reply-To: <fb4290b261d2265e9cf64cd6f67df9d0e1a1ac74.camel@gmail.com>
On Fri, Apr 10, 2026 at 02:42:53PM -0700, Eduard Zingerman wrote:
> On Fri, 2026-04-10 at 23:39 +0200, Paul Chaignon wrote:
>
> [...]
>
> > I tested this series with Cilium's complexity test suite [1]. We have a
> > lot of different configuration and some producing larger programs than
> > covered in the cover letter.
> >
> > Overall, the impact is quite good. It reduces the number of processed
> > instructions by more than 60k instructions for some of our largest
> > programs. It also increases the number of processed instructions by up
> > to 20k in fewer other cases, but I think it's manageable because they
> > are not the largest programs so we have some room. The mean diff over
> > all programs is a reduction of a few thousands processed instructions.
>
> Hi Paul,
>
> Thank you for testing this series!
> Are the regressing program open-source?
> If so, could you please point to a few?
Hi Eduard,
Yes, all programs tested are from Cilium OSS. [1] shows the overall
results grouped by program (each line covers multiple configurations).
I've uploaded details for programs (a) tail_nodeport_nat_ingress_ipv4
and (b) tail_handle_ipv4_cont with configurations for which your
patchset causes an increase in complexity. The object file at [2]
contains program (a) compiled with the Cilium configuration from [3].
The impact of your patchset on that program is at [4]. For program (b),
see [5, 6, 7].
These programs are quite large so not the easiest to dig into.
Unfortunately, I'm not seeing anything obvious that differentiate the
programs with a positive impact from those with a negative impact.
Don't hesitate if I can do anything to help! I can also share the
verifier logs if that helps.
1: https://pchaigno.github.io/assets/static-liveness-complexity/complexity-results.png
2: https://pchaigno.github.io/assets/static-liveness-complexity/bpf_host-3.o
3: https://github.com/cilium/cilium/blob/12955851fc2f0c25f01d0df27a66c0ed6c275f59/bpf/complexity-tests/netnext/bpf_host/3.txt
4: https://pchaigno.github.io/assets/static-liveness-complexity/bpf_host-build3.png
5: https://pchaigno.github.io/assets/static-liveness-complexity/bpf_lxc-7.o
6: https://github.com/cilium/cilium/blob/12955851fc2f0c25f01d0df27a66c0ed6c275f59/bpf/complexity-tests/netnext/bpf_lxc/7.txt
7: https://pchaigno.github.io/assets/static-liveness-complexity/bpf_lxc-build7.png
>
> [...]
next prev parent reply other threads:[~2026-04-13 13:31 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-10 20:55 [PATCH bpf-next v4 00/14] bpf: static stack liveness data flow analysis Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 01/14] bpf: share several utility functions as internal API Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 02/14] bpf: save subprogram name in bpf_subprog_info Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 03/14] bpf: Add spis_*() helpers for 4-byte stack slot bitmasks Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 04/14] bpf: make liveness.c track stack with 4-byte granularity Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 05/14] bpf: 4-byte precise clean_verifier_state Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 06/14] bpf: prepare liveness internal API for static analysis pass Eduard Zingerman
2026-04-10 20:55 ` [PATCH bpf-next v4 07/14] bpf: introduce forward arg-tracking dataflow analysis Eduard Zingerman
2026-04-10 21:44 ` bot+bpf-ci
2026-04-10 21:46 ` Eduard Zingerman
2026-04-10 22:17 ` Alexei Starovoitov
2026-04-10 20:55 ` [PATCH bpf-next v4 08/14] bpf: record arg tracking results in bpf_liveness masks Eduard Zingerman
2026-04-10 20:56 ` [PATCH bpf-next v4 09/14] bpf: simplify liveness to use (callsite, depth) keyed func_instances Eduard Zingerman
2026-04-10 21:39 ` Paul Chaignon
2026-04-10 21:42 ` Eduard Zingerman
2026-04-13 13:31 ` Paul Chaignon [this message]
2026-04-10 21:44 ` bot+bpf-ci
2026-04-10 22:33 ` Alexei Starovoitov
2026-04-10 20:56 ` [PATCH bpf-next v4 10/14] bpf: change logging scheme for live stack analysis Eduard Zingerman
2026-05-07 23:29 ` Paul Chaignon
2026-05-08 13:46 ` Eduard Zingerman
2026-05-11 17:45 ` Paul Chaignon
2026-05-11 18:54 ` Eduard Zingerman
2026-05-11 19:20 ` Kumar Kartikeya Dwivedi
2026-05-11 20:03 ` Eduard Zingerman
2026-04-10 20:56 ` [PATCH bpf-next v4 11/14] selftests/bpf: update existing tests due to liveness changes Eduard Zingerman
2026-04-10 20:56 ` [PATCH bpf-next v4 12/14] selftests/bpf: adjust verifier_log buffers Eduard Zingerman
2026-04-10 20:56 ` [PATCH bpf-next v4 13/14] selftests/bpf: add new tests for static stack liveness analysis Eduard Zingerman
2026-04-10 20:56 ` [PATCH bpf-next v4 14/14] bpf: poison dead stack slots Eduard Zingerman
2026-04-10 22:40 ` [PATCH bpf-next v4 00/14] bpf: static stack liveness data flow analysis patchwork-bot+netdevbpf
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=adzwGJXuXcVbF5H1@Tunnel \
--to=paul.chaignon@gmail.com \
--cc=alexei.starovoitov@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=eddyz87@gmail.com \
--cc=kernel-team@fb.com \
--cc=martin.lau@linux.dev \
--cc=yonghong.song@linux.dev \
/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.