From: Li Zefan <lizefan@huawei.com>
To: Tejun Heo <tj@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Cgroups <cgroups@vger.kernel.org>
Subject: Re: [PATCH v2 1/3] cgroup: fix mount failure in a corner case
Date: Mon, 30 Jun 2014 09:41:22 +0800 [thread overview]
Message-ID: <53B0C042.9030206@huawei.com> (raw)
In-Reply-To: <20140628115743.GB10829@htj.dyndns.org>
On 2014/6/28 19:58, Tejun Heo wrote:
> Hello, Li.
>
> On Fri, Jun 27, 2014 at 05:13:12PM +0800, Li Zefan wrote:
>> + for_each_subsys(ss, i) {
>> + if (!(opts.subsys_mask & (1 << i)) ||
>> + ss->root == &cgrp_dfl_root)
>> + continue;
>> +
>> + if (!percpu_ref_tryget_live(&ss->root->cgrp.self.refcnt)) {
>> + mutex_unlock(&cgroup_mutex);
>> + msleep(10);
>> + ret = restart_syscall();
>> + goto out_free;
>> + }
>
> Why not just put it immediately? We know that it's not gonna be
> destroyed while holding cgroup_mutex. It may look a bit weird but
> this is a pretty special case anyway and deferring put doesn't buy
> anything.
>
Yeah, this is better. :)
prev parent reply other threads:[~2014-06-30 1:41 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-27 7:10 [PATCH v2 1/3] cgroup: fix mount failure in a corner case Li Zefan
2014-06-27 7:10 ` [PATCH v2 2/3] kernfs: introduce kernfs_pin_sb() Li Zefan
2014-06-27 15:01 ` Tejun Heo
2014-06-27 17:48 ` Greg Kroah-Hartman
2014-06-27 7:11 ` [PATCH v2 3/3] cgroup: fix a race between cgroup_mount() and cgroup_kill_sb() Li Zefan
2014-06-27 8:16 ` [PATCH v2 1/3] cgroup: fix mount failure in a corner case Li Zefan
2014-06-27 9:13 ` Li Zefan
2014-06-28 11:58 ` Tejun Heo
2014-06-30 1:41 ` Li Zefan [this message]
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