+ mm-rename-zap_skip_check_mapping-to-should_zap_page.patch added to -mm tree

+ mm-rename-zap_skip_check_mapping-to-should_zap_page.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm: rename zap_skip_check_mapping() to should_zap_page()
has been added to the -mm tree.  Its filename is
     mm-rename-zap_skip_check_mapping-to-should_zap_page.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-rename-zap_skip_check_mapping-to-should_zap_page.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-rename-zap_skip_check_mapping-to-should_zap_page.patch

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------------------------------------------------------
From: Peter Xu <peterx@redhat.com>
Subject: mm: rename zap_skip_check_mapping() to should_zap_page()

The previous name is against the natural way people think.  Invert the
meaning and also the return value.  No functional change intended.

Link: https://lkml.kernel.org/r/20220216094810.60572-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Suggested-by: Hugh Dickins <hughd@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory.c |   17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

--- a/mm/memory.c~mm-rename-zap_skip_check_mapping-to-should_zap_page
+++ a/mm/memory.c
@@ -1326,20 +1326,19 @@ static inline bool should_zap_cows(struc
 
 /*
  * We set details->zap_mapping when we want to unmap shared but keep private
- * pages. Return true if skip zapping this page, false otherwise.
+ * pages. Return true if we should zap this page, false otherwise.
  */
-static inline bool
-zap_skip_check_mapping(struct zap_details *details, struct page *page)
+static inline bool should_zap_page(struct zap_details *details, struct page *page)
 {
 	/* If we can make a decision without *page.. */
 	if (should_zap_cows(details))
-		return false;
+		return true;
 
 	/* E.g. zero page */
 	if (!page)
-		return false;
+		return true;
 
-	return details->zap_mapping != page_rmapping(page);
+	return details->zap_mapping == page_rmapping(page);
 }
 
 static unsigned long zap_pte_range(struct mmu_gather *tlb,
@@ -1374,7 +1373,7 @@ again:
 			struct page *page;
 
 			page = vm_normal_page(vma, addr, ptent);
-			if (unlikely(zap_skip_check_mapping(details, page)))
+			if (unlikely(!should_zap_page(details, page)))
 				continue;
 			ptent = ptep_get_and_clear_full(mm, addr, pte,
 							tlb->fullmm);
@@ -1408,7 +1407,7 @@ again:
 		    is_device_exclusive_entry(entry)) {
 			struct page *page = pfn_swap_entry_to_page(entry);
 
-			if (unlikely(zap_skip_check_mapping(details, page)))
+			if (unlikely(!should_zap_page(details, page)))
 				continue;
 			pte_clear_not_present_full(mm, addr, pte, tlb->fullmm);
 			rss[mm_counter(page)]--;
@@ -1433,7 +1432,7 @@ again:
 			struct page *page;
 
 			page = pfn_swap_entry_to_page(entry);
-			if (zap_skip_check_mapping(details, page))
+			if (!should_zap_page(details, page))
 				continue;
 			rss[mm_counter(page)]--;
 		} else if (is_hwpoison_entry(entry)) {
_

Patches currently in -mm which might be from peterx@redhat.com are

mm-fix-invalid-page-pointer-returned-with-foll_pin-gups.patch
mm-dont-skip-swap-entry-even-if-zap_details-specified.patch
mm-rename-zap_skip_check_mapping-to-should_zap_page.patch
mm-change-zap_detailszap_mapping-into-even_cows.patch
mm-rework-swap-handling-of-zap_pte_range.patch