Commit f9f38f78 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Matthew Wilcox (Oracle)
Browse files

mm: refactor check_and_migrate_movable_pages 

Remove up to two levels of indentation by using continue statements
and move variables to local scope where possible.

Link: https://lkml.kernel.org/r/20220210072828.2930359-11-hch@lst.de


Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Tested-by: default avatar"Sierra Guiza, Alejandro (Alex)" <alex.sierra@amd.com>

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Christian Knig <christian.koenig@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
parent 5cbf9942

mm/gup.c

+44 −37
Original line number Diff line number Diff line
@@ -1841,32 +1841,31 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages, 
					    struct page **pages,

					    unsigned int gup_flags)

{

	unsigned long i;

	unsigned long isolation_error_count = 0;

	bool drain_allow = true;

	LIST_HEAD(movable_page_list);

	long ret = 0;

	unsigned long isolation_error_count = 0, i;

	struct page *prev_head = NULL;

	struct page *head;

	struct migration_target_control mtc = {

		.nid = NUMA_NO_NODE,

		.gfp_mask = GFP_USER | __GFP_NOWARN,

	};

	LIST_HEAD(movable_page_list);

	bool drain_allow = true;

	int ret = 0;



	for (i = 0; i < nr_pages; i++) {

		head = compound_head(pages[i]);

		struct page *head = compound_head(pages[i]);



		if (head == prev_head)

			continue;

		prev_head = head;



		if (is_pinnable_page(head))

			continue;



		/*

		 * If we get a movable page, since we are going to be pinning

		 * these entries, try to move them out if possible.

		 * Try to move out any movable page before pinning the range.

		 */

		if (!is_pinnable_page(head)) {

		if (PageHuge(head)) {

			if (!isolate_huge_page(head, &movable_page_list))

				isolation_error_count++;

			} else {

			continue;

		}



		if (!PageLRU(head) && drain_allow) {

			lru_add_drain_all();

			drain_allow = false;
@@ -1878,35 +1877,43 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages, 
		}

		list_add_tail(&head->lru, &movable_page_list);

		mod_node_page_state(page_pgdat(head),

						    NR_ISOLATED_ANON +

						    page_is_file_lru(head),

				    NR_ISOLATED_ANON + page_is_file_lru(head),

				    thp_nr_pages(head));

	}

		}

	}



	if (!list_empty(&movable_page_list) || isolation_error_count)

		goto unpin_pages;



	/*

	 * If list is empty, and no isolation errors, means that all pages are

	 * in the correct zone.

	 */

	if (list_empty(&movable_page_list) && !isolation_error_count)

	return nr_pages;



unpin_pages:

	if (gup_flags & FOLL_PIN) {

		unpin_user_pages(pages, nr_pages);

	} else {

		for (i = 0; i < nr_pages; i++)

			put_page(pages[i]);

	}



	if (!list_empty(&movable_page_list)) {

		struct migration_target_control mtc = {

			.nid = NUMA_NO_NODE,

			.gfp_mask = GFP_USER | __GFP_NOWARN,

		};



		ret = migrate_pages(&movable_page_list, alloc_migration_target,

				    NULL, (unsigned long)&mtc, MIGRATE_SYNC,

				    MR_LONGTERM_PIN, NULL);

		if (ret && !list_empty(&movable_page_list))

			putback_movable_pages(&movable_page_list);

		if (ret > 0) /* number of pages not migrated */

			ret = -ENOMEM;

	}



	return ret > 0 ? -ENOMEM : ret;

	if (ret && !list_empty(&movable_page_list))

		putback_movable_pages(&movable_page_list);

	return ret;

}

#else

static long check_and_migrate_movable_pages(unsigned long nr_pages,