The patch titled
Subject: mm/filemap: fix page cache removal for arbitrary sized THPs
has been added to the -mm tree. Its filename is
mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/filemap: fix page cache removal for arbitrary sized THPs
Patch series "Remove assumptions of THP size".
There are a number of places in the VM which assume that a THP is a PMD in
size. That's true today, and remains true after this patch series, but
this is a prerequisite for switching to arbitrary-sized THPs.
thp_nr_pages() still returns either HPAGE_PMD_NR or 1, but will be changed
later.
This patch (of 11):
page_cache_free_page() assumes THPs are PMD_SIZE; fix that assumption.
Link: https://lkml.kernel.org/r/20200908195539.25896-1-willy@xxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20200908195539.25896-2-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/filemap.c~mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps
+++ a/mm/filemap.c
@@ -249,7 +249,7 @@ static void page_cache_free_page(struct
freepage(page);
if (PageTransHuge(page) && !PageHuge(page)) {
- page_ref_sub(page, HPAGE_PMD_NR);
+ page_ref_sub(page, thp_nr_pages(page));
VM_BUG_ON_PAGE(page_count(page) <= 0, page);
} else {
put_page(page);
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-debug-do-not-dereference-i_ino-blindly.patch
mm-account-pmd-tables-like-pte-tables.patch
mm-move-pagedoublemap-bit.patch
mm-simplify-pagedoublemap-with-pf_second-policy.patch
xarray-add-xa_get_order.patch
xarray-add-xas_split.patch
mm-filemap-fix-storing-to-a-thp-shadow-entry.patch
mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
mm-memory-remove-page-fault-assumption-of-compound-page-size.patch
mm-page_owner-change-split_page_owner-to-take-a-count.patch
mm-huge_memory-fix-page_trans_huge_mapcount-assumption-of-thp-size.patch
mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch
mm-rmap-fix-assumptions-of-thp-size.patch
mm-truncate-fix-truncation-for-pages-of-arbitrary-size.patch
mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch
mm-vmscan-allow-arbitrary-sized-pages-to-be-paged-out.patch
mm-readahead-add-define_readahead.patch
mm-readahead-make-page_cache_ra_unbounded-take-a-readahead_control.patch
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
mm-readahead-add-page_cache_sync_ra-and-page_cache_async_ra.patch
harden-autofs-ioctl-table.patch
