From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx200.postini.com [74.125.245.200]) by kanga.kvack.org (Postfix) with SMTP id 1F4036B13F2 for ; Thu, 2 Feb 2012 21:50:30 -0500 (EST) Received: by iagz16 with SMTP id z16so5696069iag.14 for ; Thu, 02 Feb 2012 18:50:29 -0800 (PST) From: Sha Zhengju Subject: [PATCH] memcg: make threshold index in the right position Date: Fri, 3 Feb 2012 10:49:56 +0800 Message-Id: <1328237396-12453-1-git-send-email-handai.szj@taobao.com> In-Reply-To: <1328175919-11209-1-git-send-email-handai.szj@taobao.com> References: <1328175919-11209-1-git-send-email-handai.szj@taobao.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, cgroups@vger.kernel.org Cc: kamezawa.hiroyu@jp.fujitsu.com, kirill@shutemov.name, Sha Zhengju From: Sha Zhengju Index current_threshold may point to threshold that just equal to usage after last call of __mem_cgroup_threshold. But after registering a new event, it will change (pointing to threshold just below usage). So make it consistent here. For example: now: threshold array: 3 [5] 7 9 (usage = 6, [index] = 5) next turn (after calling __mem_cgroup_threshold): threshold array: 3 5 [7] 9 (usage = 7, [index] = 7) after registering a new event (threshold = 10): threshold array: 3 [5] 7 9 10 (usage = 7, [index] = 5) Signed-off-by: Sha Zhengju Acked-by: KAMEZAWA Hiroyuki Reviewed-by: Kirill A. Shutemov --- mm/memcontrol.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 22d94f5..95fc9f07 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -183,7 +183,7 @@ struct mem_cgroup_threshold { /* For threshold */ struct mem_cgroup_threshold_ary { - /* An array index points to threshold just below usage. */ + /* An array index points to threshold just below or equal to usage. */ int current_threshold; /* Size of entries[] */ unsigned int size; @@ -4193,7 +4193,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) usage = mem_cgroup_usage(memcg, swap); /* - * current_threshold points to threshold just below usage. + * current_threshold points to threshold just below or equal to usage. * If it's not true, a threshold was crossed after last * call of __mem_cgroup_threshold(). */ @@ -4319,14 +4319,15 @@ static int mem_cgroup_usage_register_event(struct cgroup *cgrp, /* Find current threshold */ new->current_threshold = -1; for (i = 0; i < size; i++) { - if (new->entries[i].threshold < usage) { + if (new->entries[i].threshold <= usage) { /* * new->current_threshold will not be used until * rcu_assign_pointer(), so it's safe to increment * it here. */ ++new->current_threshold; - } + } else + break; } /* Free old spare buffer and save old primary buffer as spare */ -- 1.7.4.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org