From: Tejun Heo <tj@kernel.org>
Date: Mon, 5 Mar 2012 21:15:11 +0000 (-0800)
Subject: blkcg: let blkio_group point to blkio_cgroup directly
X-Git-Tag: v3.5-rc1~42^2~75
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7ee9c5620504906e98451dc9a1945b2b9e892cb8;p=pandora-kernel.git

blkcg: let blkio_group point to blkio_cgroup directly

Currently, blkg points to the associated blkcg via its css_id.  This
unnecessarily complicates dereferencing blkcg.  Let blkg hold a
reference to the associated blkcg and point directly to it and disable
css_id on blkio_subsys.

This change requires splitting blkiocg_destroy() into
blkiocg_pre_destroy() and blkiocg_destroy() so that all blkg's can be
destroyed and all the blkcg references held by them dropped during
cgroup removal.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

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