On Fri, 4 Aug 2023 15:14:53 +0800 "Yin, Fengwei" [off-list ref] wrote:

Hi Andrew,

On 8/2/2023 8:39 PM, Yin, Fengwei wrote:

quoted

Hi Andrew,

On 7/29/2023 1:24 AM, Andrew Morton wrote:

quoted

On Sat, 29 Jul 2023 00:13:54 +0800 Yin Fengwei [off-list ref] wrote:

quoted

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.

I think I'll stage them for 6.5, with a cc:stable.

I'll drop the current three patches.  Please resend with

a) different Subject:s for all patches and

b) changelogs which fully describe the user-visible effects of the change.

Thanks.