mm/migrate.c: cleanup expected_page_refs() (f900482d) · Commits · 戴 / test

Andrea has noted that page migration code propagates page_mapping(page) through the whole migration stack down to migrate_page() function so it seems stupid to then use page_mapping(page) in expected_page_refs() instead of passed down 'mapping' argument. I agree so let's make expected_page_refs() more in line with the rest of the migration stack. Link: http://lkml.kernel.org/r/20190207112314.24872-1-jack@suse.cz Signed-off-by:

Jan Kara <jack@suse.cz> Suggested-by:

Andrea Arcangeli <aarcange@redhat.com> Reviewed-by:

Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

mm/migrate.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -374,7 +374,7 @@ unlock:
		}
		#endif

		static int expected_page_refs(struct page *page)
		static int expected_page_refs(struct address_space mapping, struct page page)
		{
		int expected_count = 1;

		@@ -384,7 +384,7 @@ static int expected_page_refs(struct page *page)
		*/
		expected_count += is_device_private_page(page);
		expected_count += is_device_public_page(page);
		if (page_mapping(page))
		if (mapping)
		expected_count += hpage_nr_pages(page) + page_has_private(page);

		return expected_count;
		@@ -405,7 +405,7 @@ int migrate_page_move_mapping(struct address_space *mapping,
		XA_STATE(xas, &mapping->i_pages, page_index(page));
		struct zone oldzone, newzone;
		int dirty;
		int expected_count = expected_page_refs(page) + extra_count;
		int expected_count = expected_page_refs(mapping, page) + extra_count;

		if (!mapping) {
		/* Anonymous page without mapping */
		@@ -750,7 +750,7 @@ static int __buffer_migrate_page(struct address_space *mapping,
		return migrate_page(mapping, newpage, page, mode);

		/* Check whether page does not have extra refs before we do more work */
		expected_count = expected_page_refs(page);
		expected_count = expected_page_refs(mapping, page);
		if (page_count(page) != expected_count)
		return -EAGAIN;

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