The patch titled
Subject: mm/vmscan: convert shrink_active_list() to use a folio
has been added to the -mm mm-unstable branch. Its filename is
mm-vmscan-convert-shrink_active_list-to-use-a-folio.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-convert-shrink_active_list-to-use-a-folio.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/vmscan: convert shrink_active_list() to use a folio
Date: Fri, 17 Jun 2022 16:42:47 +0100
Remove a few hidden calls to compound_head, saving 411 bytes of text.
Link: https://lkml.kernel.org/r/20220617154248.700416-5-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 61 +++++++++++++++++++++++---------------------------
1 file changed, 29 insertions(+), 32 deletions(-)
--- a/mm/vmscan.c~mm-vmscan-convert-shrink_active_list-to-use-a-folio
+++ a/mm/vmscan.c
@@ -26,8 +26,7 @@
#include <linux/file.h>
#include <linux/writeback.h>
#include <linux/blkdev.h>
-#include <linux/buffer_head.h> /* for try_to_release_page(),
- buffer_heads_over_limit */
+#include <linux/buffer_head.h> /* for buffer_heads_over_limit */
#include <linux/mm_inline.h>
#include <linux/backing-dev.h>
#include <linux/rmap.h>
@@ -2489,21 +2488,21 @@ shrink_inactive_list(unsigned long nr_to
}
/*
- * 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,
@@ -2513,7 +2512,7 @@ static void shrink_active_list(unsigned
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;
@@ -2538,23 +2537,21 @@ static void shrink_active_list(unsigned
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);
}
}
@@ -2562,34 +2559,34 @@ static void shrink_active_list(unsigned
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);
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-add-vma-iterator.patch
mmap-use-the-vma-iterator-in-count_vma_pages_range.patch
proc-remove-vma-rbtree-use-from-nommu.patch
arm64-remove-mmap-linked-list-from-vdso.patch
parisc-remove-mmap-linked-list-from-cache-handling.patch
powerpc-remove-mmap-linked-list-walks.patch
s390-remove-vma-linked-list-walks.patch
x86-remove-vma-linked-list-walks.patch
xtensa-remove-vma-linked-list-walks.patch
cxl-remove-vma-linked-list-walk.patch
optee-remove-vma-linked-list-walk.patch
um-remove-vma-linked-list-walk.patch
coredump-remove-vma-linked-list-walk.patch
exec-use-vma-iterator-instead-of-linked-list.patch
fs-proc-task_mmu-stop-using-linked-list-and-highest_vm_end.patch
acct-use-vma-iterator-instead-of-linked-list.patch
perf-use-vma-iterator.patch
sched-use-maple-tree-iterator-to-walk-vmas.patch
fork-use-vma-iterator.patch
mm-khugepaged-stop-using-vma-linked-list.patch
mm-ksm-use-vma-iterators-instead-of-vma-linked-list.patch
mm-mlock-use-vma-iterator-and-maple-state-instead-of-vma-linked-list.patch
mm-pagewalk-use-vma_find-instead-of-vma-linked-list.patch
i915-use-the-vma-iterator.patch
nommu-remove-uses-of-vma-linked-list.patch
mm-vmscan-convert-reclaim_clean_pages_from_list-to-folios.patch
mm-vmscan-convert-isolate_lru_pages-to-use-a-folio.patch
mm-vmscan-convert-move_pages_to_lru-to-use-a-folio.patch
mm-vmscan-convert-shrink_active_list-to-use-a-folio.patch
mm-vmscan-convert-reclaim_pages-to-use-a-folio.patch
