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>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory.c b/mm/memory.c
index a7bf87c..48b008b 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1326,20 +1326,19 @@ static inline bool should_zap_cows(struct zap_details *details)
 
 /*
  * 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. the caller passes NULL for the case of a 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)]--;
@@ -1429,7 +1428,7 @@ 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)) {