On 2024/3/28 2:49, Vishal Moola wrote:
On Wed, Mar 27, 2024 at 10:10:32PM +0800, Kefeng Wang wrote:
This moves folio_get_nontail_page() before non-lru movable pages check,
and directly call isolate_movable_folio() to save compound_head() calls,
since the reference count of the non-lru movable page is increased, a
folio_put() is need() whether the folio is isolated or not.
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
mm/compaction.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index 807b58e6eb68..74ac65daaed1 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1097,41 +1097,41 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
}
}
+ /*
+ * Be careful not to clear PageLRU until after we're
+ * sure the page is not being freed elsewhere -- the
+ * page release code relies on it.
+ */
+ folio = folio_get_nontail_page(page);
+ if (unlikely(!folio))
+ goto isolate_fail;
+
If you wanted to move this, I think this should be part of your first
patch (or prior to it). It would make your first patch be more sensible as
ok, will re-order the patches.
is. You could then also consider making isolate_movable_folio() more similar
to folio_isolate_lru() if you really wanted to.
Maybe just rename it folio_isolate_movable and no more changes now.
Thanks.
/*
* Check may be lockless but that's ok as we recheck later.
* It's possible to migrate LRU and non-lru movable pages.
* Skip any other type of page
*/
- if (!PageLRU(page)) {
+ if (!folio_test_lru(folio)) {
/*
* __PageMovable can return false positive so we need
* to verify it under page_lock.
*/
- if (unlikely(__PageMovable(page)) &&
- !PageIsolated(page)) {
+ if (unlikely(__folio_test_movable(folio)) &&
+ !folio_test_isolated(folio)) {
if (locked) {
unlock_page_lruvec_irqrestore(locked, flags);
locked = NULL;
}
- if (isolate_movable_page(page, mode)) {
- folio = page_folio(page);
+ if (isolate_movable_folio(folio, mode)) {
+ folio_put(folio);
goto isolate_success;
}
}
- goto isolate_fail;
+ goto isolate_fail_put;
}
- /*
- * Be careful not to clear PageLRU until after we're
- * sure the page is not being freed elsewhere -- the
- * page release code relies on it.
- */
- folio = folio_get_nontail_page(page);
- if (unlikely(!folio))
- goto isolate_fail;
-
/*
* Migration will fail if an anonymous page is pinned in memory,
* so avoid taking lru_lock and isolating it unnecessarily in an
--
2.27.0
