diff --git a/mm/migrate.c b/mm/migrate.c index b61abe529107fc..db3f154446af4e 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1112,9 +1112,8 @@ static void migrate_folio_done(struct folio *src, /* Obtain the lock on page, remove all ptes. */ static int migrate_folio_unmap(new_page_t get_new_page, free_page_t put_new_page, unsigned long private, struct folio *src, - struct folio **dstp, int force, - enum migrate_mode mode, enum migrate_reason reason, - struct list_head *ret) + struct folio **dstp, enum migrate_mode mode, + enum migrate_reason reason, struct list_head *ret) { struct folio *dst; int rc = -EAGAIN; @@ -1144,7 +1143,7 @@ static int migrate_folio_unmap(new_page_t get_new_page, free_page_t put_new_page dst->private = NULL; if (!folio_trylock(src)) { - if (!force || mode == MIGRATE_ASYNC) + if (mode == MIGRATE_ASYNC) goto out; /* @@ -1182,8 +1181,6 @@ static int migrate_folio_unmap(new_page_t get_new_page, free_page_t put_new_page rc = -EBUSY; goto out; } - if (!force) - goto out; folio_wait_writeback(src); } @@ -1497,6 +1494,9 @@ static inline int try_split_folio(struct folio *folio, struct list_head *split_f #define NR_MAX_BATCHED_MIGRATION 512 #endif #define NR_MAX_MIGRATE_PAGES_RETRY 10 +#define NR_MAX_MIGRATE_ASYNC_RETRY 3 +#define NR_MAX_MIGRATE_SYNC_RETRY \ + (NR_MAX_MIGRATE_PAGES_RETRY - NR_MAX_MIGRATE_ASYNC_RETRY) struct migrate_pages_stats { int nr_succeeded; /* Normal and large folios migrated successfully, in @@ -1678,8 +1678,7 @@ static int migrate_pages_batch(struct list_head *from, new_page_t get_new_page, } rc = migrate_folio_unmap(get_new_page, put_new_page, private, - folio, &dst, pass > 2, mode, - reason, ret_folios); + folio, &dst, mode, reason, ret_folios); /* * The rules are: * Success: folio will be freed @@ -1857,6 +1856,51 @@ static int migrate_pages_batch(struct list_head *from, new_page_t get_new_page, return rc; } +static int migrate_pages_sync(struct list_head *from, new_page_t get_new_page, + free_page_t put_new_page, unsigned long private, + enum migrate_mode mode, int reason, struct list_head *ret_folios, + struct list_head *split_folios, struct migrate_pages_stats *stats) +{ + int rc, nr_failed = 0; + LIST_HEAD(folios); + struct migrate_pages_stats astats; + + memset(&astats, 0, sizeof(astats)); + /* Try to migrate in batch with MIGRATE_ASYNC mode firstly */ + rc = migrate_pages_batch(from, get_new_page, put_new_page, private, MIGRATE_ASYNC, + reason, &folios, split_folios, &astats, + NR_MAX_MIGRATE_ASYNC_RETRY); + stats->nr_succeeded += astats.nr_succeeded; + stats->nr_thp_succeeded += astats.nr_thp_succeeded; + stats->nr_thp_split += astats.nr_thp_split; + if (rc < 0) { + stats->nr_failed_pages += astats.nr_failed_pages; + stats->nr_thp_failed += astats.nr_thp_failed; + list_splice_tail(&folios, ret_folios); + return rc; + } + stats->nr_thp_failed += astats.nr_thp_split; + nr_failed += astats.nr_thp_split; + /* + * Fall back to migrate all failed folios one by one synchronously. All + * failed folios except split THPs will be retried, so their failure + * isn't counted + */ + list_splice_tail_init(&folios, from); + while (!list_empty(from)) { + list_move(from->next, &folios); + rc = migrate_pages_batch(&folios, get_new_page, put_new_page, + private, mode, reason, ret_folios, + split_folios, stats, NR_MAX_MIGRATE_SYNC_RETRY); + list_splice_tail_init(&folios, ret_folios); + if (rc < 0) + return rc; + nr_failed += rc; + } + + return nr_failed; +} + /* * migrate_pages - migrate the folios specified in a list, to the free folios * supplied as the target for the page migration @@ -1888,7 +1932,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, enum migrate_mode mode, int reason, unsigned int *ret_succeeded) { int rc, rc_gather; - int nr_pages, batch; + int nr_pages; struct folio *folio, *folio2; LIST_HEAD(folios); LIST_HEAD(ret_folios); @@ -1904,10 +1948,6 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, if (rc_gather < 0) goto out; - if (mode == MIGRATE_ASYNC) - batch = NR_MAX_BATCHED_MIGRATION; - else - batch = 1; again: nr_pages = 0; list_for_each_entry_safe(folio, folio2, from, lru) { @@ -1918,16 +1958,20 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, } nr_pages += folio_nr_pages(folio); - if (nr_pages >= batch) + if (nr_pages >= NR_MAX_BATCHED_MIGRATION) break; } - if (nr_pages >= batch) + if (nr_pages >= NR_MAX_BATCHED_MIGRATION) list_cut_before(&folios, from, &folio2->lru); else list_splice_init(from, &folios); - rc = migrate_pages_batch(&folios, get_new_page, put_new_page, private, - mode, reason, &ret_folios, &split_folios, &stats, - NR_MAX_MIGRATE_PAGES_RETRY); + if (mode == MIGRATE_ASYNC) + rc = migrate_pages_batch(&folios, get_new_page, put_new_page, private, + mode, reason, &ret_folios, &split_folios, &stats, + NR_MAX_MIGRATE_PAGES_RETRY); + else + rc = migrate_pages_sync(&folios, get_new_page, put_new_page, private, + mode, reason, &ret_folios, &split_folios, &stats); list_splice_tail_init(&folios, &ret_folios); if (rc < 0) { rc_gather = rc;