From 2c26fdd70c3094fa3e84caf9ef434911933d5477 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Wed, 7 Jan 2009 18:08:10 -0800 Subject: memcg: revert gfp mask fix My patch, memcg-fix-gfp_mask-of-callers-of-charge.patch changed gfp_mask of callers of charge to be GFP_HIGHUSER_MOVABLE for showing what will happen at memory reclaim. But in recent discussion, it's NACKed because it sounds ugly. This patch is for reverting it and add some clean up to gfp_mask of callers of charge. No behavior change but need review before generating HUNK in deep queue. This patch also adds explanation to meaning of gfp_mask passed to charge functions in memcontrol.h. Signed-off-by: KAMEZAWA Hiroyuki Cc: Balbir Singh Cc: Daisuke Nishimura Cc: Hugh Dickins Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 2fdd1380bf0a..59ac95a64508 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -26,6 +26,16 @@ struct page; struct mm_struct; #ifdef CONFIG_CGROUP_MEM_RES_CTLR +/* + * All "charge" functions with gfp_mask should use GFP_KERNEL or + * (gfp_mask & GFP_RECLAIM_MASK). In current implementatin, memcg doesn't + * alloc memory but reclaims memory from all available zones. So, "where I want + * memory from" bits of gfp_mask has no meaning. So any bits of that field is + * available but adding a rule is better. charge functions' gfp_mask should + * be set to GFP_KERNEL or gfp_mask & GFP_RECLAIM_MASK for avoiding ambiguous + * codes. + * (Of course, if memcg does memory allocation in future, GFP_KERNEL is sane.) + */ extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask); -- cgit v1.2.3