Commit 8567712f authored by Kefeng Wang's avatar Kefeng Wang Committed by Peng Zhang
Browse files

mm: mprotect: use a folio in change_pte_range() 

mainline inclusion
from mainline-v6.7-rc1
commit ec1778807a8053d14cde7cfd75fbd66e0c7b9c9f
category: other
bugzilla: https://gitee.com/openeuler/kernel/issues/I8JQWQ

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ec1778807a8053d14cde7cfd75fbd66e0c7b9c9f

--------------------------------

Use a folio in change_pte_range() to save three compound_head() calls.
Since now only normal and PMD-mapped page is handled by numa balancing,
it is enough to only update the entire folio's access time.

Link: https://lkml.kernel.org/r/20231018140806.2783514-10-wangkefeng.wang@huawei.com


Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
parent 202662df

mm/mprotect.c

+9 −7
Original line number Diff line number Diff line
@@ -114,7 +114,7 @@ static long change_pte_range(struct mmu_gather *tlb, 
			 * pages. See similar comment in change_huge_pmd.

			 */

			if (prot_numa) {

				struct page *page;

				struct folio *folio;

				int nid;

				bool toptier;
@@ -122,13 +122,14 @@ static long change_pte_range(struct mmu_gather *tlb, 
				if (pte_protnone(oldpte))

					continue;



				page = vm_normal_page(vma, addr, oldpte);

				if (!page || is_zone_device_page(page) || PageKsm(page))

				folio = vm_normal_folio(vma, addr, oldpte);

				if (!folio || folio_is_zone_device(folio) ||

				    folio_test_ksm(folio))

					continue;



				/* Also skip shared copy-on-write pages */

				if (is_cow_mapping(vma->vm_flags) &&

				    page_count(page) != 1)

				    folio_ref_count(folio) != 1)

					continue;



				/*
@@ -136,14 +137,15 @@ static long change_pte_range(struct mmu_gather *tlb, 
				 * it cannot move them all from MIGRATE_ASYNC

				 * context.

				 */

				if (page_is_file_lru(page) && PageDirty(page))

				if (folio_is_file_lru(folio) &&

				    folio_test_dirty(folio))

					continue;



				/*

				 * Don't mess with PTEs if page is already on the node

				 * a single-threaded process is running on.

				 */

				nid = page_to_nid(page);

				nid = folio_nid(folio);

				if (target_node == nid)

					continue;

				toptier = node_is_toptier(nid);
@@ -157,7 +159,7 @@ static long change_pte_range(struct mmu_gather *tlb, 
					continue;

				if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING &&

				    !toptier)

					xchg_page_access_time(page,

					folio_xchg_access_time(folio,

						jiffies_to_msecs(jiffies));

			}