Commit 19979497 authored by Vishal Moola (Oracle)'s avatar Vishal Moola (Oracle) Committed by Andrew Morton
Browse files

mm/migrate: convert isolate_movable_page() to use folios 

Removes 6 calls to compound_head() and prepares the function to take in a
folio instead of page argument.

Link: https://lkml.kernel.org/r/20230130214352.40538-4-vishal.moola@gmail.com


Signed-off-by: default avatarVishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent da707a6d

mm/migrate.c

+20 −19
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ 


int isolate_movable_page(struct page *page, isolate_mode_t mode)

{

	struct folio *folio = folio_get_nontail_page(page);

	const struct movable_operations *mops;



	/*
@@ -71,11 +72,11 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) 
	 * the put_page() at the end of this block will take care of

	 * release this page, thus avoiding a nasty leakage.

	 */

	if (unlikely(!get_page_unless_zero(page)))

	if (!folio)

		goto out;



	if (unlikely(PageSlab(page)))

		goto out_putpage;

	if (unlikely(folio_test_slab(folio)))

		goto out_putfolio;

	/* Pairs with smp_wmb() in slab freeing, e.g. SLUB's __free_slab() */

	smp_rmb();

	/*
@@ -83,12 +84,12 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) 
	 * we use non-atomic bitops on newly allocated page flags so

	 * unconditionally grabbing the lock ruins page's owner side.

	 */

	if (unlikely(!__PageMovable(page)))

		goto out_putpage;

	if (unlikely(!__folio_test_movable(folio)))

		goto out_putfolio;

	/* Pairs with smp_wmb() in slab allocation, e.g. SLUB's alloc_slab_page() */

	smp_rmb();

	if (unlikely(PageSlab(page)))

		goto out_putpage;

	if (unlikely(folio_test_slab(folio)))

		goto out_putfolio;



	/*

	 * As movable pages are not isolated from LRU lists, concurrent
@@ -101,29 +102,29 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) 
	 * lets be sure we have the page lock

	 * before proceeding with the movable page isolation steps.

	 */

	if (unlikely(!trylock_page(page)))

		goto out_putpage;

	if (unlikely(!folio_trylock(folio)))

		goto out_putfolio;



	if (!PageMovable(page) || PageIsolated(page))

	if (!folio_test_movable(folio) || folio_test_isolated(folio))

		goto out_no_isolated;



	mops = page_movable_ops(page);

	VM_BUG_ON_PAGE(!mops, page);

	mops = folio_movable_ops(folio);

	VM_BUG_ON_FOLIO(!mops, folio);



	if (!mops->isolate_page(page, mode))

	if (!mops->isolate_page(&folio->page, mode))

		goto out_no_isolated;



	/* Driver shouldn't use PG_isolated bit of page->flags */

	WARN_ON_ONCE(PageIsolated(page));

	SetPageIsolated(page);

	unlock_page(page);

	WARN_ON_ONCE(folio_test_isolated(folio));

	folio_set_isolated(folio);

	folio_unlock(folio);



	return 0;



out_no_isolated:

	unlock_page(page);

out_putpage:

	put_page(page);

	folio_unlock(folio);

out_putfolio:

	folio_put(folio);

out:

	return -EBUSY;

}