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From: Tejun Heo <tj@kernel.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Kernel development list <linux-kernel@vger.kernel.org>,
	Eric Biederman <ebiederm@xmission.com>,
	Greg Kroah-Hartman <gregkh@suse.de>,
	Kay Sievers <kay.sievers@vrfy.org>
Subject: Re: Sysfs attributes racing with unregistration
Date: Wed, 4 Jan 2012 10:20:41 -0800	[thread overview]
Message-ID: <20120104182041.GO31746@google.com> (raw)
In-Reply-To: <Pine.LNX.4.44L0.1201041300130.1505-100000@iolanthe.rowland.org>

Hello,

On Wed, Jan 04, 2012 at 01:13:41PM -0500, Alan Stern wrote:
> Now, looking through the code, I wonder why sysfs_{get,put}_active() 
> and sysfs_deactivate() don't use a real rwsem.  Why go to all the 
> effort of imitating one?  Is it just to save space?

Hmmm... maybe there was something which prevented that or maybe I was
just being stupid.  I don't really remember.  Space is a fairly
important consideration too.  Depending on configuration, there can be
a LOT of sysfs_dirents and memory consumption from sysfs has been a
real problem.

Thanks.

-- 
tejun

      reply	other threads:[~2012-01-04 18:20 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-04 16:52 Sysfs attributes racing with unregistration Alan Stern
2012-01-04 17:18 ` Tejun Heo
2012-01-04 18:13   ` Eric W. Biederman
2012-01-04 19:41     ` Alan Stern
2012-01-05  3:07       ` Eric W. Biederman
2012-01-05 15:13         ` Revoking filesystems [was Re: Sysfs attributes racing with unregistration] Alan Stern
2012-01-05 15:32           ` Tejun Heo
2012-01-05 16:03             ` Eric W. Biederman
2012-01-05 16:44               ` Tejun Heo
2012-01-05 16:47               ` Alan Stern
2012-01-05 17:11                 ` Tejun Heo
2012-01-05 18:27                 ` Ted Ts'o
2012-01-05 18:36                   ` Tejun Heo
2012-01-05 19:28                     ` Ted Ts'o
2012-01-05 20:52                       ` Tejun Heo
2012-01-06  6:25                       ` Alexander E. Patrakov
2012-01-07 21:01                       ` Revoking filesystems [was Re: Sysfs attributes racing withunregistration] Milton Miller
2012-01-05 20:43                     ` Revoking filesystems [was Re: Sysfs attributes racing with unregistration] Eric W. Biederman
2012-01-05 20:55                       ` Tejun Heo
2012-01-05 18:38                   ` Christoph Hellwig
2012-01-05 15:52           ` Eric W. Biederman
2013-01-14 15:11             ` watchdog code anish kumar
2012-01-05 18:18           ` Revoking filesystems [was Re: Sysfs attributes racing with unregistration] Greg KH
2012-01-04 18:13   ` Sysfs attributes racing with unregistration Alan Stern
2012-01-04 18:20     ` Tejun Heo [this message]

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