mm, memcg: do not retry precharge charges
authorDavid Rientjes <[email protected]>
Tue, 24 Jan 2017 23:18:10 +0000 (15:18 -0800)
committerLinus Torvalds <[email protected]>
Wed, 25 Jan 2017 00:26:14 +0000 (16:26 -0800)
When memory.move_charge_at_immigrate is enabled and precharges are
depleted during move, mem_cgroup_move_charge_pte_range() will attempt to
increase the size of the precharge.

Prevent precharges from ever looping by setting __GFP_NORETRY.  This was
probably the intention of the GFP_KERNEL & ~__GFP_NORETRY, which is
pointless as written.

Fixes: 0029e19ebf84 ("mm: memcontrol: remove explicit OOM parameter in charge path")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: David Rientjes <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
mm/memcontrol.c

index a63a8f8326647b92bdc63810c8a93be96047f748..b822e158b319e8f2f02ecbfe76c31b6466be51f1 100644 (file)
@@ -4353,9 +4353,9 @@ static int mem_cgroup_do_precharge(unsigned long count)
                return ret;
        }
 
-       /* Try charges one by one with reclaim */
+       /* Try charges one by one with reclaim, but do not retry */
        while (count--) {
-               ret = try_charge(mc.to, GFP_KERNEL & ~__GFP_NORETRY, 1);
+               ret = try_charge(mc.to, GFP_KERNEL __GFP_NORETRY, 1);
                if (ret)
                        return ret;
                mc.precharge++;