On Fri, May 03, 2024 at 11:03:24AM -0700, Andrii Nakryiko wrote:

On Thu, May 2, 2024 at 1:04 PM Jiri Olsa [off-list ref] wrote:

quoted

On Thu, May 02, 2024 at 09:43:02AM -0700, Andrii Nakryiko wrote:

quoted

On Thu, May 2, 2024 at 5:23 AM Jiri Olsa [off-list ref] wrote:

quoted

hi,
as part of the effort on speeding up the uprobes [0] coming with
return uprobe optimization by using syscall instead of the trap
on the uretprobe trampoline.

The speed up depends on instruction type that uprobe is installed
and depends on specific HW type, please check patch 1 for details.

Patches 1-6 are based on bpf-next/master, but path 1 and 2 are
apply-able on linux-trace.git tree probes/for-next branch.
Patch 7 is based on man-pages master.

v4 changes:
  - added acks [Oleg,Andrii,Masami]
  - reworded the man page and adding more info to NOTE section [Masami]
  - rewrote bpf tests not to use trace_pipe [Andrii]
  - cc-ed linux-man list

Also available at:
  https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  uretprobe_syscall

It looks great to me, thanks! Unfortunately BPF CI build is broken,
probably due to some of the Makefile additions, please investigate and
fix (or we'll need to fix something on BPF CI side), but it looks like
you'll need another revision, unfortunately.

pw-bot: cr

  [0] https://github.com/kernel-patches/bpf/actions/runs/8923849088/job/24509002194

yes, I think it's missing the 32-bit libc for uprobe_compat binary,
probably it needs to be added to github.com:libbpf/ci.git setup-build-env/action.yml ?
hm but I'm not sure how to test it, need to check

You can create a custom PR directly against Github repo
(kernel-patches/bpf) and BPF CI will run all the tests on your custom
code. This way you can iterate without spamming the mailing list.

I'm running CI tests like that, but I think I need to change the action
which is in other repo (github.com:libbpf/ci.git)

But I'm just wondering if it's worth complicating setup just for
testing this x32 compat mode. So maybe just dropping one of those
patches would be better?

well, we had compat process crashing on uretprobe because of this change,
so I rather keep the test.. or it can go in later on when the CI stuff is
figured out.. I got busy with the shadow stack issue today, will check on
the CI PR next week

jirka