[PATCH v2 2/6] mm/migrate_device: further convert migrate_device_unmap() to folios

From: Sidhartha Kumar
Date: Fri Feb 16 2024 - 16:16:01 EST


migrate_device_unmap() already has a folio, we can use the folio
versions of is_zone_device_page() and putback_lru_page.

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
---

v1 -> v2:
use migrate_pfn_to_folio() to directly work with a folio
per Alistair Popple.

mm/migrate_device.c | 30 +++++++++++++-----------------
1 file changed, 13 insertions(+), 17 deletions(-)

diff --git a/mm/migrate_device.c b/mm/migrate_device.c
index b6c27c76e1a0b..3d3c2593b5b64 100644
--- a/mm/migrate_device.c
+++ b/mm/migrate_device.c
@@ -368,42 +368,40 @@ static unsigned long migrate_device_unmap(unsigned long *src_pfns,
lru_add_drain();

for (i = 0; i < npages; i++) {
- struct page *page = migrate_pfn_to_page(src_pfns[i]);
- struct folio *folio;
+ struct folio *folio = migrate_pfn_to_folio(src_pfns[i]);

- if (!page) {
+ if (!folio) {
if (src_pfns[i] & MIGRATE_PFN_MIGRATE)
unmapped++;
continue;
}

/* ZONE_DEVICE pages are not on LRU */
- if (!is_zone_device_page(page)) {
- if (!PageLRU(page) && allow_drain) {
+ if (!folio_is_zone_device(folio)) {
+ if (!folio_test_lru(folio) && allow_drain) {
/* Drain CPU's lru cache */
lru_add_drain_all();
allow_drain = false;
}

- if (!isolate_lru_page(page)) {
+ if (!folio_isolate_lru(folio)) {
src_pfns[i] &= ~MIGRATE_PFN_MIGRATE;
restore++;
continue;
}

/* Drop the reference we took in collect */
- put_page(page);
+ folio_put(folio);
}

- folio = page_folio(page);
if (folio_mapped(folio))
try_to_migrate(folio, 0);

- if (page_mapped(page) ||
- !migrate_vma_check_page(page, fault_page)) {
- if (!is_zone_device_page(page)) {
- get_page(page);
- putback_lru_page(page);
+ if (folio_mapped(folio) ||
+ !migrate_vma_check_page(&folio->page, fault_page)) {
+ if (!folio_is_zone_device(folio)) {
+ folio_get(folio);
+ folio_putback_lru(folio);
}

src_pfns[i] &= ~MIGRATE_PFN_MIGRATE;
@@ -415,13 +413,11 @@ static unsigned long migrate_device_unmap(unsigned long *src_pfns,
}

for (i = 0; i < npages && restore; i++) {
- struct page *page = migrate_pfn_to_page(src_pfns[i]);
- struct folio *folio;
+ struct folio *folio = migrate_pfn_to_folio(src_pfns[i]);

- if (!page || (src_pfns[i] & MIGRATE_PFN_MIGRATE))
+ if (!folio || (src_pfns[i] & MIGRATE_PFN_MIGRATE))
continue;

- folio = page_folio(page);
remove_migration_ptes(folio, folio, false);

src_pfns[i] = 0;
--
2.42.0