memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order

Since commit 857f213 ("memcg, oom: remove unnecessary check in
mem_cgroup_oom_synchronize()"), memcg_oom_gfp_mask and memcg_oom_order are
no longer used any more.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Xiu Jianfeng <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Shakeel Butt <[email protected]>
Reviewed-by: Roman Gushchin <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Benjamin Segall <[email protected]>
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Dietmar Eggemann <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt (Google) <[email protected]>
Cc: Valentin Schneider <[email protected]>
Cc: Vincent Guittot <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: Xiu Jianfeng

include/linux/sched.h

@@ -1448,8 +1448,6 @@ struct task_struct {
 
 #ifdef CONFIG_MEMCG
 	struct mem_cgroup		*memcg_in_oom;
-	gfp_t				memcg_oom_gfp_mask;
-	int				memcg_oom_order;
 
 	/* Number of pages to reclaim on returning to userland: */
 	unsigned int			memcg_nr_pages_over_high;

mm/memcontrol.c

@@ -2188,8 +2188,6 @@ static bool mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order)
 		if (current->in_user_fault) {
 			css_get(&memcg->css);
 			current->memcg_in_oom = memcg;
-			current->memcg_oom_gfp_mask = mask;
-			current->memcg_oom_order = order;
 		}
 		return false;
 	}