From patchwork Sat Nov 3 08:38:33 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tejun Heo X-Patchwork-Id: 1691591 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 797CFDFB7B for ; Sat, 3 Nov 2012 08:40:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754755Ab2KCIj3 (ORCPT ); Sat, 3 Nov 2012 04:39:29 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:33714 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754694Ab2KCIj1 (ORCPT ); Sat, 3 Nov 2012 04:39:27 -0400 Received: by mail-pb0-f46.google.com with SMTP id rr4so2919353pbb.19 for ; Sat, 03 Nov 2012 01:39:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=7h2l3UaLCqWz2cDJo1FL/G10AcNjSDoeITD36sPXhwk=; b=ebekpU+1sDJP54jF7RlBHWPGH0FXhwPHC1fzMNBjhPHWOKmbtM+RJ5dN4a4pWHSgTY adlDHr5TqcWB6F3VAmEhz3ESr8S4IOKSsM0hLUp+WIZ8ZiPAWS+E863Rc0EkBV279jYK 7r28LRInzyFshIHnqelBsMTjs53Dwyu09VzJ5JLc+tUsfOnum0S3tILio/HrkTD4P1Cr CvIL3QiPcXLleCPEy6WOFeGxJ3W9SD+FSM7CjBKB07sLDBUD3y8tmQxY3OXe3QY39JK0 zYMDCkgh/9o8bUTK0zOLH8KhJRalwbNdHegj5qIVN3isJrb1NBRIRxihqyS9sHQkQrBY dMrQ== Received: by 10.68.227.197 with SMTP id sc5mr5714442pbc.157.1351931966663; Sat, 03 Nov 2012 01:39:26 -0700 (PDT) Received: from htj.dyndns.org (50-78-106-165-static.hfc.comcastbusiness.net. [50.78.106.165]) by mx.google.com with ESMTPS id o7sm7090130pay.14.2012.11.03.01.39.22 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 03 Nov 2012 01:39:25 -0700 (PDT) From: Tejun Heo To: lizefan@huawei.com, mhocko@suse.cz, rjw@sisk.pl Cc: containers@lists.linux-foundation.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, fweisbec@gmail.com, Tejun Heo Subject: [PATCH 7/9] cgroup_freezer: introduce CGROUP_FREEZING_[SELF|PARENT] Date: Sat, 3 Nov 2012 01:38:33 -0700 Message-Id: <1351931915-1701-8-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1351931915-1701-1-git-send-email-tj@kernel.org> References: <1351931915-1701-1-git-send-email-tj@kernel.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Introduce FREEZING_SELF and FREEZING_PARENT and make FREEZING OR of the two flags. This is to prepare for full hierarchy support. freezer_apply_date() is updated such that it can handle setting and clearing of both flags. The two flags are also exposed to userland via read-only files self_freezing and parent_freezing. Other than the added cgroupfs files, this patch doesn't introduce any behavior change. Signed-off-by: Tejun Heo Reviewed-by: KAMEZAWA Hiroyuki Reviewed-by: Michal Hocko --- kernel/cgroup_freezer.c | 55 ++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 47 insertions(+), 8 deletions(-) diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index e76aa9f..b8ad93c 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -23,8 +23,12 @@ #include enum freezer_state_flags { - CGROUP_FREEZING = (1 << 1), /* this freezer is freezing */ + CGROUP_FREEZING_SELF = (1 << 1), /* this freezer is freezing */ + CGROUP_FREEZING_PARENT = (1 << 2), /* the parent freezer is freezing */ CGROUP_FROZEN = (1 << 3), /* this and its descendants frozen */ + + /* mask for all FREEZING flags */ + CGROUP_FREEZING = CGROUP_FREEZING_SELF | CGROUP_FREEZING_PARENT, }; struct freezer { @@ -245,8 +249,13 @@ static void unfreeze_cgroup(struct freezer *freezer) * freezer_apply_state - apply state change to a single cgroup_freezer * @freezer: freezer to apply state change to * @freeze: whether to freeze or unfreeze + * @state: CGROUP_FREEZING_* flag to set or clear + * + * Set or clear @state on @cgroup according to @freeze, and perform + * freezing or thawing as necessary. */ -static void freezer_apply_state(struct freezer *freezer, bool freeze) +static void freezer_apply_state(struct freezer *freezer, bool freeze, + unsigned int state) { /* also synchronizes against task migration, see freezer_attach() */ lockdep_assert_held(&freezer->lock); @@ -254,13 +263,19 @@ static void freezer_apply_state(struct freezer *freezer, bool freeze) if (freeze) { if (!(freezer->state & CGROUP_FREEZING)) atomic_inc(&system_freezing_cnt); - freezer->state |= CGROUP_FREEZING; + freezer->state |= state; freeze_cgroup(freezer); } else { - if (freezer->state & CGROUP_FREEZING) - atomic_dec(&system_freezing_cnt); - freezer->state &= ~(CGROUP_FREEZING | CGROUP_FROZEN); - unfreeze_cgroup(freezer); + bool was_freezing = freezer->state & CGROUP_FREEZING; + + freezer->state &= ~state; + + if (!(freezer->state & CGROUP_FREEZING)) { + if (was_freezing) + atomic_dec(&system_freezing_cnt); + freezer->state &= ~CGROUP_FROZEN; + unfreeze_cgroup(freezer); + } } } @@ -275,7 +290,7 @@ static void freezer_change_state(struct freezer *freezer, bool freeze) { /* update @freezer */ spin_lock_irq(&freezer->lock); - freezer_apply_state(freezer, freeze); + freezer_apply_state(freezer, freeze, CGROUP_FREEZING_SELF); spin_unlock_irq(&freezer->lock); } @@ -295,6 +310,20 @@ static int freezer_write(struct cgroup *cgroup, struct cftype *cft, return 0; } +static u64 freezer_self_freezing_read(struct cgroup *cgroup, struct cftype *cft) +{ + struct freezer *freezer = cgroup_freezer(cgroup); + + return (bool)(freezer->state & CGROUP_FREEZING_SELF); +} + +static u64 freezer_parent_freezing_read(struct cgroup *cgroup, struct cftype *cft) +{ + struct freezer *freezer = cgroup_freezer(cgroup); + + return (bool)(freezer->state & CGROUP_FREEZING_PARENT); +} + static struct cftype files[] = { { .name = "state", @@ -302,6 +331,16 @@ static struct cftype files[] = { .read_seq_string = freezer_read, .write_string = freezer_write, }, + { + .name = "self_freezing", + .flags = CFTYPE_NOT_ON_ROOT, + .read_u64 = freezer_self_freezing_read, + }, + { + .name = "parent_freezing", + .flags = CFTYPE_NOT_ON_ROOT, + .read_u64 = freezer_parent_freezing_read, + }, { } /* terminate */ };