Messages in this thread | | | Date | Fri, 4 Aug 2023 15:14:53 +0800 | Subject | Re: [PATCH 0/2] don't use mapcount() to check large folio sharing | From | "Yin, Fengwei" <> |
| |
Hi Andrew,
On 8/2/2023 8:39 PM, Yin, Fengwei wrote: > Hi Andrew, > > On 7/29/2023 1:24 AM, Andrew Morton wrote: >> On Sat, 29 Jul 2023 00:13:54 +0800 Yin Fengwei <fengwei.yin@intel.com> wrote: >> >>> In madvise_cold_or_pageout_pte_range() and madvise_free_pte_range(), >>> folio_mapcount() is used to check whether the folio is shared. But it's >>> not correct as folio_mapcount() returns total mapcount of large folio. >>> >>> Use folio_estimated_sharers() here as the estimated number is enough. >> >> What are the user-visible runtime effects of these changes? >> >> (and please try to avoid using the same Subject: for different patches) >> > > Can you hold on these patches to mm-unstable? I think we need to wait for > David's work on folio_maybe_mapped_shared() and redo the fix base on that. > Thanks and sorry for the noise. Sorry for bothering you again for this patchset.
Let me explain the situation here: - The reason to hold on the patches to mm-unstable is that I don't want to promote the fix in this patch (using folio_estimated_sharers()). The correct way is waiting for folio_maybe_mapped_shared() from David.
Merging these patches motivate using folio_estimated_sharers() in other places. So once folio_maybe_mapped_shared() is ready, we need to replace folio_estimated_sharers() with folio_maybe_mapped_shared().
- For this specific patches, if they are suitable for stable, we may want to merge it (special for stable branch. I assume folio_maybe_mapped_shared() may not be back ported to stable branch).
So how do we deal with this situation? Thanks in advance.
Regards Yin, Fengwei
> > > Regards > Yin, Fengwei
| |