The function just return 2 results, so use a 'switch' to deal with its
result is unnecessary, and simplify it to a bool func as Vlastimil
suggested.
Also removed 'goto' in using by reusing list_move().
Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
mm/compaction.c | 2 +-
mm/vmscan.c | 53 ++++++++++++++++++++++++-------------------------
2 files changed, 27 insertions(+), 28 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index b68931854253..8d71ffebe6cb 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -988,7 +988,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
if (unlikely(!get_page_unless_zero(page)))
goto isolate_fail;
- if (__isolate_lru_page_prepare(page, isolate_mode) != 0)
+ if (!__isolate_lru_page_prepare(page, isolate_mode))
goto isolate_fail_put;
/* Try isolate the page */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index c6f94e55c3fe..7f32c1979804 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1540,7 +1540,7 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone,
*/
int __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode)
{
- int ret = -EBUSY;
+ int ret = false;
/* Only take pages on the LRU. */
if (!PageLRU(page))
@@ -1590,7 +1590,7 @@ int __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode)
if ((mode & ISOLATE_UNMAPPED) && page_mapped(page))
return ret;
- return 0;
+ return true;
}
/*
@@ -1674,35 +1674,34 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
* only when the page is being freed somewhere else.
*/
scan += nr_pages;
- switch (__isolate_lru_page_prepare(page, mode)) {
- case 0:
+ if (!__isolate_lru_page_prepare(page, mode)) {
+ /* else it is being freed elsewhere */
+ list_move(&page->lru, src);
+ continue;
+ }
+ /*
+ * 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.
+ */
+ if (unlikely(!get_page_unless_zero(page))) {
+ list_move(&page->lru, src);
+ continue;
+ }
+
+ if (!TestClearPageLRU(page)) {
/*
- * 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.
+ * This page may in other isolation path,
+ * but we still hold lru_lock.
*/
- if (unlikely(!get_page_unless_zero(page)))
- goto busy;
-
- if (!TestClearPageLRU(page)) {
- /*
- * This page may in other isolation path,
- * but we still hold lru_lock.
- */
- put_page(page);
- goto busy;
- }
-
- nr_taken += nr_pages;
- nr_zone_taken[page_zonenum(page)] += nr_pages;
- list_move(&page->lru, dst);
- break;
-
- default:
-busy:
- /* else it is being freed elsewhere */
+ put_page(page);
list_move(&page->lru, src);
+ continue;
}
+
+ nr_taken += nr_pages;
+ nr_zone_taken[page_zonenum(page)] += nr_pages;
+ list_move(&page->lru, dst);
}
/*
--
2.29.GIT
