[patch 02/10] mm: swapfile: clean up unuse_pte race handling

[Johannes Weiner <hannes@cmpxchg.org>]

The conditional mem_cgroup_cancel_charge_swapin() is a leftover from
when the function would continue to reestablish the page even after
mem_cgroup_try_charge_swapin() failed.  After 85d9fc8 "memcg: fix
refcnt handling at swapoff", the condition is always true when this
code is reached.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
---
 mm/swapfile.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 64408be..75881ca 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -845,8 +845,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
 
 	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 	if (unlikely(!pte_same(*pte, swp_entry_to_pte(entry)))) {
-		if (ret > 0)
-			mem_cgroup_cancel_charge_swapin(memcg);
+		mem_cgroup_cancel_charge_swapin(memcg);
 		ret = 0;
 		goto out;
 	}
-- 
1.7.7.6

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