Now there are several places will validate if a page can migrate or not,
so factoring out these validation into a new function to make them more
maintainable.
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 6 ++++++
mm/internal.h | 1 +
mm/memory.c | 30 ++++++++++++++++++++++++++++++
mm/migrate.c | 19 -------------------
4 files changed, 37 insertions(+), 19 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4465915711c3..4a9b34a89854 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1540,11 +1540,17 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
spin_unlock(vmf->ptl);
writable = false;
+ if (!numa_page_can_migrate(vma, page)) {
+ put_page(page);
+ goto migrate_fail;
+ }
+
migrated = migrate_misplaced_page(page, vma, target_nid);
if (migrated) {
flags |= TNF_MIGRATED;
page_nid = target_nid;
} else {
+migrate_fail:
flags |= TNF_MIGRATE_FAIL;
vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) {
diff --git a/mm/internal.h b/mm/internal.h
index f59a53111817..1e00b8a30910 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -933,6 +933,7 @@ void __vunmap_range_noflush(unsigned long start, unsigned long end);
int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
unsigned long addr, int page_nid, int *flags);
+bool numa_page_can_migrate(struct vm_area_struct *vma, struct page *page);
void free_zone_device_page(struct page *page);
int migrate_device_coherent_page(struct page *page);
diff --git a/mm/memory.c b/mm/memory.c
index 12647d139a13..fc6f6b7a70e1 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4735,6 +4735,30 @@ int numa_migrate_prep(struct page *page, struct vm_area_struct *vma,
return mpol_misplaced(page, vma, addr);
}
+bool numa_page_can_migrate(struct vm_area_struct *vma, struct page *page)
+{
+ /*
+ * Don't migrate file pages that are mapped in multiple processes
+ * with execute permissions as they are probably shared libraries.
+ */
+ if (page_mapcount(page) != 1 && page_is_file_lru(page) &&
+ (vma->vm_flags & VM_EXEC))
+ return false;
+
+ /*
+ * Also do not migrate dirty pages as not all filesystems can move
+ * dirty pages in MIGRATE_ASYNC mode which is a waste of cycles.
+ */
+ if (page_is_file_lru(page) && PageDirty(page))
+ return false;
+
+ /* Do not migrate THP mapped by multiple processes */
+ if (PageTransHuge(page) && total_mapcount(page) > 1)
+ return false;
+
+ return true;
+}
+
static vm_fault_t do_numa_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
@@ -4815,11 +4839,17 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
pte_unmap_unlock(vmf->pte, vmf->ptl);
writable = false;
+ if (!numa_page_can_migrate(vma, page)) {
+ put_page(page);
+ goto migrate_fail;
+ }
+
/* Migrate to the requested node */
if (migrate_misplaced_page(page, vma, target_nid)) {
page_nid = target_nid;
flags |= TNF_MIGRATED;
} else {
+migrate_fail:
flags |= TNF_MIGRATE_FAIL;
vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
vmf->address, &vmf->ptl);
diff --git a/mm/migrate.c b/mm/migrate.c
index e21d5a7e7447..9cc98fb1d6ec 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2485,10 +2485,6 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
VM_BUG_ON_PAGE(order && !PageTransHuge(page), page);
- /* Do not migrate THP mapped by multiple processes */
- if (PageTransHuge(page) && total_mapcount(page) > 1)
- return 0;
-
/* Avoid migrating to a node that is nearly full */
if (!migrate_balanced_pgdat(pgdat, nr_pages)) {
int z;
@@ -2533,21 +2529,6 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
LIST_HEAD(migratepages);
int nr_pages = thp_nr_pages(page);
- /*
- * Don't migrate file pages that are mapped in multiple processes
- * with execute permissions as they are probably shared libraries.
- */
- if (page_mapcount(page) != 1 && page_is_file_lru(page) &&
- (vma->vm_flags & VM_EXEC))
- goto out;
-
- /*
- * Also do not migrate dirty pages as not all filesystems can move
- * dirty pages in MIGRATE_ASYNC mode which is a waste of cycles.
- */
- if (page_is_file_lru(page) && PageDirty(page))
- goto out;
-
isolated = numamigrate_isolate_page(pgdat, page);
if (!isolated)
goto out;
--
2.39.3
