From 07f67a8dedc0788f3f91d945bc6e987cf9cccd4a Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 17 Jun 2022 16:42:47 +0100 Subject: [PATCH] mm/vmscan: convert shrink_active_list() to use a folio Remove a few hidden calls to compound_head, saving 411 bytes of text. Link: https://lkml.kernel.org/r/20220617154248.700416-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton --- mm/vmscan.c | 61 +++++++++++++++++++++++++++++-------------------------------- 1 file changed, 29 insertions(+), 32 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 2ec5bcb..8e22a11 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -26,8 +26,7 @@ #include #include #include -#include /* for try_to_release_page(), - buffer_heads_over_limit */ +#include /* for buffer_heads_over_limit */ #include #include #include @@ -2483,21 +2482,21 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, } /* - * shrink_active_list() moves pages from the active LRU to the inactive LRU. + * shrink_active_list() moves folios from the active LRU to the inactive LRU. * - * We move them the other way if the page is referenced by one or more + * We move them the other way if the folio is referenced by one or more * processes. * - * If the pages are mostly unmapped, the processing is fast and it is + * If the folios are mostly unmapped, the processing is fast and it is * appropriate to hold lru_lock across the whole operation. But if - * the pages are mapped, the processing is slow (folio_referenced()), so - * we should drop lru_lock around each page. It's impossible to balance - * this, so instead we remove the pages from the LRU while processing them. - * It is safe to rely on PG_active against the non-LRU pages in here because - * nobody will play with that bit on a non-LRU page. + * the folios are mapped, the processing is slow (folio_referenced()), so + * we should drop lru_lock around each folio. It's impossible to balance + * this, so instead we remove the folios from the LRU while processing them. + * It is safe to rely on the active flag against the non-LRU folios in here + * because nobody will play with that bit on a non-LRU folio. * - * The downside is that we have to touch page->_refcount against each page. - * But we had to alter page->flags anyway. + * The downside is that we have to touch folio->_refcount against each folio. + * But we had to alter folio->flags anyway. */ static void shrink_active_list(unsigned long nr_to_scan, struct lruvec *lruvec, @@ -2507,7 +2506,7 @@ static void shrink_active_list(unsigned long nr_to_scan, unsigned long nr_taken; unsigned long nr_scanned; unsigned long vm_flags; - LIST_HEAD(l_hold); /* The pages which were snipped off */ + LIST_HEAD(l_hold); /* The folios which were snipped off */ LIST_HEAD(l_active); LIST_HEAD(l_inactive); unsigned nr_deactivate, nr_activate; @@ -2532,23 +2531,21 @@ static void shrink_active_list(unsigned long nr_to_scan, while (!list_empty(&l_hold)) { struct folio *folio; - struct page *page; cond_resched(); folio = lru_to_folio(&l_hold); list_del(&folio->lru); - page = &folio->page; - if (unlikely(!page_evictable(page))) { - putback_lru_page(page); + if (unlikely(!folio_evictable(folio))) { + folio_putback_lru(folio); continue; } if (unlikely(buffer_heads_over_limit)) { - if (page_has_private(page) && trylock_page(page)) { - if (page_has_private(page)) - try_to_release_page(page, 0); - unlock_page(page); + if (folio_get_private(folio) && folio_trylock(folio)) { + if (folio_get_private(folio)) + filemap_release_folio(folio, 0); + folio_unlock(folio); } } @@ -2556,34 +2553,34 @@ static void shrink_active_list(unsigned long nr_to_scan, if (folio_referenced(folio, 0, sc->target_mem_cgroup, &vm_flags) != 0) { /* - * Identify referenced, file-backed active pages and + * Identify referenced, file-backed active folios and * give them one more trip around the active list. So * that executable code get better chances to stay in - * memory under moderate memory pressure. Anon pages + * memory under moderate memory pressure. Anon folios * are not likely to be evicted by use-once streaming - * IO, plus JVM can create lots of anon VM_EXEC pages, + * IO, plus JVM can create lots of anon VM_EXEC folios, * so we ignore them here. */ - if ((vm_flags & VM_EXEC) && page_is_file_lru(page)) { - nr_rotated += thp_nr_pages(page); - list_add(&page->lru, &l_active); + if ((vm_flags & VM_EXEC) && folio_is_file_lru(folio)) { + nr_rotated += folio_nr_pages(folio); + list_add(&folio->lru, &l_active); continue; } } - ClearPageActive(page); /* we are de-activating */ - SetPageWorkingset(page); - list_add(&page->lru, &l_inactive); + folio_clear_active(folio); /* we are de-activating */ + folio_set_workingset(folio); + list_add(&folio->lru, &l_inactive); } /* - * Move pages back to the lru list. + * Move folios back to the lru list. */ spin_lock_irq(&lruvec->lru_lock); nr_activate = move_pages_to_lru(lruvec, &l_active); nr_deactivate = move_pages_to_lru(lruvec, &l_inactive); - /* Keep all free pages in l_active list */ + /* Keep all free folios in l_active list */ list_splice(&l_inactive, &l_active); __count_vm_events(PGDEACTIVATE, nr_deactivate); -- 2.7.4