On 16.04.23 20:11, Hugh Dickins wrote:
On Tue, 4 Apr 2023, Andrew Morton wrote:
On Mon, 3 Apr 2023 16:18:32 -0400 Zi Yan <zi.yan@xxxxxxxx> wrote:
File folio supports any order and people would like to support flexible orders
for anonymous folio[1] too. Currently, split_huge_page() only splits a huge
page to order-0 pages, but splitting to orders higher than 0 is also useful.
This patchset adds support for splitting a huge page to any lower order pages
and uses it during file folio truncate operations.
This series (and its v1 & v2) don't appear to have much in the way of
detailed review. As it's at v3 and has been fairly stable I'll queue
it up for some testing now, but I do ask that some reviewers go through
it please.
Andrew, please don't let this series drift into 6.4-rc1.
I've seen a bug or two (I'll point out in response to those patches),
but overall I don't see what the justification for the series is: done
because it could be done, it seems to me, but liable to add surprises.
The cover letter says "splitting to orders higher than 0 is also useful",
but it's not clear why; and the infrastructure provided seems unsuited
to the one use provided - I'll say more on that truncation patch.
I agree. Maybe this patch set is something we want to have in the future
once actual consumers that can benefit are in place, such that we can
show actual performance numbers with/without.
Until then, "365 insertions(+), 68 deletions(-)" certainly needs some
reasonable motivation.
--
Thanks,
David / dhildenb
