Re: [PATCH] mm: migrate: Do not retry 10 times for the subpages of fail-to-migrate THP

[Baolin Wang]

On 7/28/2022 2:16 PM, Huang, Ying wrote:
> Hi, Baolin,
>
> Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> writes:
>
> > If THP is failed to migrate due to -ENOSYS or -ENOMEM case, the THP will
> > be split, and the subpages of fail-to-migrate THP will be tried to migrate
> > again, so we should not account the retry counter in the second loop, since
> > we already accounted 'nr_thp_failed' in the first loop.
> >
> > Moreover we also do not need retry 10 times for -EAGAIN case for the subpages
> > of fail-to-migrate THP in the second loop, since we already regarded the
> > THP as migration failure, and save some migration time (for the worst case,
> > will try 512 * 10 times) according to previous discussion [1].
> >
> > [1] https://lore.kernel.org/linux-mm/87r13a7n04.fsf@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
> >
> > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
>
> I have tested this patch, and it works as expected.
>
> Tested-by: "Huang, Ying" <ying.huang@xxxxxxxxx>

Thanks.

> > ---
> > Note, this patch is based on the patch set [1] from Huang Ying.
> > [1] https://lore.kernel.org/linux-mm/20220711084948.274787-1-ying.huang@xxxxxxxxx/
>
> Please this patch is based on my patchset that hasn't been merged.  I
> can add it as the last patch of my migrate_pages failure path fixing
> patchset if you don't object.

Sure, please fold it into your series. Thanks for helping.