Re: [PATCH 0/7] riscv: Various text patching improvements

Alexandre Ghiti
2024-02-20T22:12:26Z

On Mon, Feb 19, 2024 at 1:25 PM Björn Töpel <bjorn@kernel.org> wrote:
>
> Andrea Parri <parri.andrea@gmail.com> writes:
>
> > Hi Samuel,
> >
> > On Sun, Feb 11, 2024 at 06:55:11PM -0800, Samuel Holland wrote:
> >> Here are a few changes to minimize calls to stop_machine() and
> >> flush_icache_*() in the various text patching functions, as well as
> >> to simplify the code.
> >>
> >>
> >> Samuel Holland (7):
> >> riscv: jump_label: Batch icache maintenance
> >> riscv: jump_label: Simplify assembly syntax
> >> riscv: kprobes: Use patch_text_nosync() for insn slots
> >> riscv: Simplify text patching loops
> >> riscv: Pass patch_text() the length in bytes
> >> riscv: Use offset_in_page() in text patching functions
> >> riscv: Remove extra variable in patch_text_nosync()
> >
> > This does look like a nice clean-up. Just curious (a "teach me"-like question),
> > how did you test these changes? kselftests, micro-benchmarks, other?
> >
> > BTW, I recall a parallel work from Alex and Bjorn [1] that might have some minor
> > conflict with these changes; + both of them to Cc: for further sync.
>
> Indeed! I think Alex is still working on the v2.

Actually I was blocked by Andrea's comment about patch_map(), but it's
not related so I can spin another version soon. I'd say mine should
land first because AIA support may get into 6.9 (?) and then this
patch would be needed. In case you re-spin another version, can you
rebase on top of it? Unless you have another solution of course.

Thanks,

Alex