Re: [PATCH v3] mm: fs: invalidate bh_lrus for only cold path

[Linus Torvalds]

On Tue, Sep 7, 2021 at 2:24 PM Minchan Kim <minchan@xxxxxxxxxx> wrote:
>
> kernel test robot reported the regression of fio.write_iops[1]
> with [2].
>
> Since lru_add_drain is called frequently, invalidate bh_lrus
> there could increase bh_lrus cache miss ratio, which needs
> more IO in the end.
>
> This patch moves the bh_lrus invalidation from the hot path(
> e.g., zap_page_range, pagevec_release) to cold path(i.e.,
> lru_add_drain_all, lru_cache_disable).

Was this confirmed to fix the regression?

I only see the "tested with 5.14" that the regression was still there

   https://lore.kernel.org/lkml/034fc860-d0d0-0c61-09d2-3c41c4f020c6@xxxxxxxxx/

I don't see a confirmation that this patch fixed it.

It looks likely, but if you have the confirmation somewhere, it would
help to link that too.

Or did I miss it?

           Linus