Re: [PATCH v15 00/19] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph

[Google]

On Wed, 18 Sep 2024 23:22:41 +0200
Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx> wrote:

> On Sun, Sep 15, 2024 at 11:09 AM Masami Hiramatsu (Google)
> <mhiramat@xxxxxxxxxx> wrote:
> >
> > Hi,
> >
> > Here is the 15th version of the series to re-implement the fprobe on
> > function-graph tracer. The previous version is;
> >
> > https://lore.kernel.org/all/172615368656.133222.2336770908714920670.stgit@devnote2/
> >
> > This version rebased on Steve's calltime change[1] instead of the last
> > patch in the previous series, and adds a bpf patch to add get_entry_ip()
> > for arm64. Note that [1] is not included in this series, so please use
> > the git branch[2].
> >
> 
> With LPC and Kernel Recipes back-to-back I won't have time to look
> through the code, but I did manage to run some benchmarks tonight, and
> they look pretty good now, thanks! Seems like the kprobe regression is
> gone, and kretprobes are a bit faster. So, nice work, thanks!
> 
> BEFORE
> ======
> kprobe         :   25.052 ± 0.032M/s
> kprobe-multi   :   28.102 ± 0.167M/s
> kretprobe      :   10.724 ± 0.008M/s
> kretprobe-multi:   11.337 ± 0.054M/s
> 
> AFTER
> =====
> kprobe         :   25.206 ± 0.026M/s
> kprobe-multi   :   30.167 ± 0.148M/s
> kretprobe      :   10.714 ± 0.016M/s
> kretprobe-multi:   13.436 ± 0.328M/s

Thanks for reevaluate the series!
This results look nice.

Thank you,

> 
> > [1] https://lore.kernel.org/all/20240914214805.779822616@xxxxxxxxxxx/
> > [2] https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git/log/?h=topic/fprobe-on-fgraph
> >
> 
> [...]


-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>