The patch titled
Subject: khugepaged: remove hpage from collapse_file()
has been added to the -mm mm-unstable branch. Its filename is
khugepaged-remove-hpage-from-collapse_file.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/khugepaged-remove-hpage-from-collapse_file.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: khugepaged: remove hpage from collapse_file()
Date: Wed, 3 Apr 2024 18:18:34 +0100
Use new_folio throughout where we had been using hpage.
Link: https://lkml.kernel.org/r/20240403171838.1445826-6-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/trace/events/huge_memory.h | 6 +-
mm/khugepaged.c | 77 +++++++++++++--------------
2 files changed, 42 insertions(+), 41 deletions(-)
--- a/include/trace/events/huge_memory.h~khugepaged-remove-hpage-from-collapse_file
+++ a/include/trace/events/huge_memory.h
@@ -207,10 +207,10 @@ TRACE_EVENT(mm_khugepaged_scan_file,
);
TRACE_EVENT(mm_khugepaged_collapse_file,
- TP_PROTO(struct mm_struct *mm, struct page *hpage, pgoff_t index,
+ TP_PROTO(struct mm_struct *mm, struct folio *new_folio, pgoff_t index,
bool is_shmem, unsigned long addr, struct file *file,
int nr, int result),
- TP_ARGS(mm, hpage, index, addr, is_shmem, file, nr, result),
+ TP_ARGS(mm, new_folio, index, addr, is_shmem, file, nr, result),
TP_STRUCT__entry(
__field(struct mm_struct *, mm)
__field(unsigned long, hpfn)
@@ -224,7 +224,7 @@ TRACE_EVENT(mm_khugepaged_collapse_file,
TP_fast_assign(
__entry->mm = mm;
- __entry->hpfn = hpage ? page_to_pfn(hpage) : -1;
+ __entry->hpfn = new_folio ? folio_pfn(new_folio) : -1;
__entry->index = index;
__entry->addr = addr;
__entry->is_shmem = is_shmem;
--- a/mm/khugepaged.c~khugepaged-remove-hpage-from-collapse_file
+++ a/mm/khugepaged.c
@@ -1780,30 +1780,27 @@ static int collapse_file(struct mm_struc
struct collapse_control *cc)
{
struct address_space *mapping = file->f_mapping;
- struct page *hpage;
struct page *page;
- struct page *tmp;
+ struct page *tmp, *dst;
struct folio *folio, *new_folio;
pgoff_t index = 0, end = start + HPAGE_PMD_NR;
LIST_HEAD(pagelist);
XA_STATE_ORDER(xas, &mapping->i_pages, start, HPAGE_PMD_ORDER);
int nr_none = 0, result = SCAN_SUCCEED;
bool is_shmem = shmem_file(file);
- int nr = 0;
VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem);
VM_BUG_ON(start & (HPAGE_PMD_NR - 1));
result = alloc_charge_folio(&new_folio, mm, cc);
- hpage = &new_folio->page;
if (result != SCAN_SUCCEED)
goto out;
- __SetPageLocked(hpage);
+ __folio_set_locked(new_folio);
if (is_shmem)
- __SetPageSwapBacked(hpage);
- hpage->index = start;
- hpage->mapping = mapping;
+ __folio_set_swapbacked(new_folio);
+ new_folio->index = start;
+ new_folio->mapping = mapping;
/*
* Ensure we have slots for all the pages in the range. This is
@@ -2036,20 +2033,24 @@ xa_unlocked:
* The old pages are locked, so they won't change anymore.
*/
index = start;
+ dst = folio_page(new_folio, 0);
list_for_each_entry(page, &pagelist, lru) {
while (index < page->index) {
- clear_highpage(hpage + (index % HPAGE_PMD_NR));
+ clear_highpage(dst);
index++;
+ dst++;
}
- if (copy_mc_highpage(hpage + (page->index % HPAGE_PMD_NR), page) > 0) {
+ if (copy_mc_highpage(dst, page) > 0) {
result = SCAN_COPY_MC;
goto rollback;
}
index++;
+ dst++;
}
while (index < end) {
- clear_highpage(hpage + (index % HPAGE_PMD_NR));
+ clear_highpage(dst);
index++;
+ dst++;
}
if (nr_none) {
@@ -2077,16 +2078,17 @@ xa_unlocked:
}
/*
- * If userspace observed a missing page in a VMA with a MODE_MISSING
- * userfaultfd, then it might expect a UFFD_EVENT_PAGEFAULT for that
- * page. If so, we need to roll back to avoid suppressing such an
- * event. Since wp/minor userfaultfds don't give userspace any
- * guarantees that the kernel doesn't fill a missing page with a zero
- * page, so they don't matter here.
+ * If userspace observed a missing page in a VMA with
+ * a MODE_MISSING userfaultfd, then it might expect a
+ * UFFD_EVENT_PAGEFAULT for that page. If so, we need to
+ * roll back to avoid suppressing such an event. Since
+ * wp/minor userfaultfds don't give userspace any
+ * guarantees that the kernel doesn't fill a missing
+ * page with a zero page, so they don't matter here.
*
- * Any userfaultfds registered after this point will not be able to
- * observe any missing pages due to the previously inserted retry
- * entries.
+ * Any userfaultfds registered after this point will
+ * not be able to observe any missing pages due to the
+ * previously inserted retry entries.
*/
vma_interval_tree_foreach(vma, &mapping->i_mmap, start, end) {
if (userfaultfd_missing(vma)) {
@@ -2111,33 +2113,32 @@ immap_locked:
xas_lock_irq(&xas);
}
- folio = page_folio(hpage);
- nr = folio_nr_pages(folio);
if (is_shmem)
- __lruvec_stat_mod_folio(folio, NR_SHMEM_THPS, nr);
+ __lruvec_stat_mod_folio(new_folio, NR_SHMEM_THPS, HPAGE_PMD_NR);
else
- __lruvec_stat_mod_folio(folio, NR_FILE_THPS, nr);
+ __lruvec_stat_mod_folio(new_folio, NR_FILE_THPS, HPAGE_PMD_NR);
if (nr_none) {
- __lruvec_stat_mod_folio(folio, NR_FILE_PAGES, nr_none);
+ __lruvec_stat_mod_folio(new_folio, NR_FILE_PAGES, nr_none);
/* nr_none is always 0 for non-shmem. */
- __lruvec_stat_mod_folio(folio, NR_SHMEM, nr_none);
+ __lruvec_stat_mod_folio(new_folio, NR_SHMEM, nr_none);
}
/*
- * Mark hpage as uptodate before inserting it into the page cache so
- * that it isn't mistaken for an fallocated but unwritten page.
+ * Mark new_folio as uptodate before inserting it into the
+ * page cache so that it isn't mistaken for an fallocated but
+ * unwritten page.
*/
- folio_mark_uptodate(folio);
- folio_ref_add(folio, HPAGE_PMD_NR - 1);
+ folio_mark_uptodate(new_folio);
+ folio_ref_add(new_folio, HPAGE_PMD_NR - 1);
if (is_shmem)
- folio_mark_dirty(folio);
- folio_add_lru(folio);
+ folio_mark_dirty(new_folio);
+ folio_add_lru(new_folio);
/* Join all the small entries into a single multi-index entry. */
xas_set_order(&xas, start, HPAGE_PMD_ORDER);
- xas_store(&xas, folio);
+ xas_store(&xas, new_folio);
WARN_ON_ONCE(xas_error(&xas));
xas_unlock_irq(&xas);
@@ -2148,7 +2149,7 @@ immap_locked:
retract_page_tables(mapping, start);
if (cc && !cc->is_khugepaged)
result = SCAN_PTE_MAPPED_HUGEPAGE;
- folio_unlock(folio);
+ folio_unlock(new_folio);
/*
* The collapse has succeeded, so free the old pages.
@@ -2193,13 +2194,13 @@ rollback:
smp_mb();
}
- hpage->mapping = NULL;
+ new_folio->mapping = NULL;
- unlock_page(hpage);
- put_page(hpage);
+ folio_unlock(new_folio);
+ folio_put(new_folio);
out:
VM_BUG_ON(!list_empty(&pagelist));
- trace_mm_khugepaged_collapse_file(mm, hpage, index, is_shmem, addr, file, nr, result);
+ trace_mm_khugepaged_collapse_file(mm, new_folio, index, is_shmem, addr, file, HPAGE_PMD_NR, result);
return result;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-always-initialise-folio-_deferred_list.patch
mm-create-folio_flag_false-and-folio_type_ops-macros.patch
mm-remove-folio_prep_large_rmappable.patch
mm-support-page_mapcount-on-page_has_type-pages.patch
mm-turn-folio_test_hugetlb-into-a-pagetype.patch
mm-turn-folio_test_hugetlb-into-a-pagetype-fix.patch
mm-remove-a-call-to-compound_head-from-is_page_hwpoison.patch
mm-free-up-pg_slab.patch
mm-free-up-pg_slab-fix.patch
mm-improve-dumping-of-mapcount-and-page_type.patch
hugetlb-remove-mention-of-destructors.patch
sh-remove-use-of-pg_arch_1-on-individual-pages.patch
xtensa-remove-uses-of-pg_arch_1-on-individual-pages.patch
mm-make-page_ext_get-take-a-const-argument.patch
mm-make-folio_test_idle-and-folio_test_young-take-a-const-argument.patch
mm-make-is_free_buddy_page-take-a-const-argument.patch
mm-make-page_mapped-take-a-const-argument.patch
mm-convert-arch_clear_hugepage_flags-to-take-a-folio.patch
mm-convert-arch_clear_hugepage_flags-to-take-a-folio-fix.patch
slub-remove-use-of-page-flags.patch
remove-references-to-page-flags-in-documentation.patch
proc-rewrite-stable_page_flags.patch
proc-rewrite-stable_page_flags-fix.patch
sparc-use-is_huge_zero_pmd.patch
mm-add-is_huge_zero_folio.patch
mm-add-pmd_folio.patch
mm-convert-migrate_vma_collect_pmd-to-use-a-folio.patch
mm-convert-huge_zero_page-to-huge_zero_folio.patch
mm-convert-do_huge_pmd_anonymous_page-to-huge_zero_folio.patch
dax-use-huge_zero_folio.patch
mm-rename-mm_put_huge_zero_page-to-mm_put_huge_zero_folio.patch
mm-use-rwsem-assertion-macros-for-mmap_lock.patch
filemap-remove-__set_page_dirty.patch
mm-correct-page_mapped_in_vma-for-large-folios.patch
mm-remove-vma_address.patch
mm-rename-vma_pgoff_address-back-to-vma_address.patch
khugepaged-inline-hpage_collapse_alloc_folio.patch
khugepaged-convert-alloc_charge_hpage-to-alloc_charge_folio.patch
khugepaged-remove-hpage-from-collapse_huge_page.patch
khugepaged-pass-a-folio-to-__collapse_huge_page_copy.patch
khugepaged-remove-hpage-from-collapse_file.patch
khugepaged-use-a-folio-throughout-collapse_file.patch
khugepaged-use-a-folio-throughout-hpage_collapse_scan_file.patch
