mm: remove SWAP_MLOCK in ttu
ttu doesn't need to return SWAP_MLOCK. Instead, just return SWAP_FAIL
because it means the page is not-swappable so it should move to another
LRU list(active or unevictable). putback friends will move it to right
list depending on the page's LRU flag.
Link: http://lkml.kernel.org/r/1489555493-14659-6-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 1b0cd4c..3630d4d 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -297,6 +297,5 @@ static inline int page_mkclean(struct page *page)
#define SWAP_SUCCESS 0
#define SWAP_AGAIN 1
#define SWAP_FAIL 2
-#define SWAP_MLOCK 3
#endif /* _LINUX_RMAP_H */
diff --git a/mm/rmap.c b/mm/rmap.c
index 171db51..45f41d4 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1329,7 +1329,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
*/
mlock_vma_page(page);
}
- ret = SWAP_MLOCK;
+ ret = SWAP_FAIL;
page_vma_mapped_walk_done(&pvmw);
break;
}
@@ -1506,7 +1506,6 @@ static int page_mapcount_is_zero(struct page *page)
* SWAP_SUCCESS - we succeeded in removing all mappings
* SWAP_AGAIN - we missed a mapping, try again later
* SWAP_FAIL - the page is unswappable
- * SWAP_MLOCK - page is mlocked.
*/
int try_to_unmap(struct page *page, enum ttu_flags flags)
{
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f1fd388..cfd2651 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -987,7 +987,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
sc->nr_scanned++;
if (unlikely(!page_evictable(page)))
- goto cull_mlocked;
+ goto activate_locked;
if (!sc->may_unmap && page_mapped(page))
goto keep_locked;
@@ -1152,8 +1152,6 @@ static unsigned long shrink_page_list(struct list_head *page_list,
goto activate_locked;
case SWAP_AGAIN:
goto keep_locked;
- case SWAP_MLOCK:
- goto cull_mlocked;
case SWAP_SUCCESS:
; /* try to free the page below */
}
@@ -1295,20 +1293,16 @@ static unsigned long shrink_page_list(struct list_head *page_list,
list_add(&page->lru, &free_pages);
continue;
-cull_mlocked:
- if (PageSwapCache(page))
- try_to_free_swap(page);
- unlock_page(page);
- list_add(&page->lru, &ret_pages);
- continue;
-
activate_locked:
/* Not a candidate for swapping, so reclaim swap space. */
- if (PageSwapCache(page) && mem_cgroup_swap_full(page))
+ if (PageSwapCache(page) && (mem_cgroup_swap_full(page) ||
+ PageMlocked(page)))
try_to_free_swap(page);
VM_BUG_ON_PAGE(PageActive(page), page);
- SetPageActive(page);
- pgactivate++;
+ if (!PageMlocked(page)) {
+ SetPageActive(page);
+ pgactivate++;
+ }
keep_locked:
unlock_page(page);
keep: