From: Levente Kurusa <levex@linux.com>
To: Tejun Heo <tj@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Greg KH <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 21/38] workqueue: add missing put_device call
Date: Thu, 19 Dec 2013 16:42:16 +0100 [thread overview]
Message-ID: <52B313D8.6090508@linux.com> (raw)
In-Reply-To: <CAOS58YO7Ot69kv=2UOTDORMAtgL2EOq-voEj3JLCDb8Rv=LABA@mail.gmail.com>
[+Cc Greg]
On 12/19/2013 04:34 PM, Tejun Heo wrote:
> Hello,
>
> On Thu, Dec 19, 2013 at 10:31 AM, Levente Kurusa <levex@linux.com> wrote:
>> The reason I removed the kfree() was because the put_device() will decrement
>> wq_dev->dev's reference count to zero (it is set to one by device_register) and hence the
>> wq_device_release() will be called. Now, this effectively does the same the kfree() call
>> would have done but also driver core is notified.
>
> Yeah, I know it does the same thing. It's just not the right way to do it.
>
>> Also, if you take a look at the comment for the device_register() function, it explicitly
>> says NOT to kfree the struct device, but instead call put_device() and let the device's release()
>> function take care.
>
> Greg, the API as described by the comment is really weird and
> unconventional. Failed calls are not supposed to have side effects
> which require explicit cleanup. Can we please update the comment?
>
Yes, it was already discussed that it would be more sane to have
device_register() call put_device() if it would fail, but Greg
said that the API was designed so that no kfree()s happen in the core.
--
Regards,
Levente Kurusa
next prev parent reply other threads:[~2013-12-19 15:42 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-19 15:03 [PATCH 01/38] sh: dma-sysfs: add missing put_device call Levente Kurusa
2013-12-19 15:03 ` [PATCH 02/38] powerpc: qe_lib: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 03/38] powerpc: cell: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 04/38] powerpc: kernel: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 05/38] sparc: " Levente Kurusa
2013-12-27 17:43 ` David Miller
2013-12-19 15:03 ` [PATCH 06/38] arm: mach-s3c64: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 07/38] arm: locomo: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 08/38] arm: mach-rpc: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 09/38] arm: mach-imx: add missing put_device calls Levente Kurusa
2013-12-19 15:03 ` [PATCH 10/38] arm: exynos: add missing put_device call Levente Kurusa
2013-12-19 15:03 ` [PATCH 11/38] arm: mach-integrator: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 12/38] arm: s5pv210: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 13/38] arm: s390: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 14/38] mips: txx9: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 15/38] mips: txx9: 7segled: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 16/38] mips: sgi-ip22: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 17/38] parisc: kernel: " Levente Kurusa
2013-12-19 15:29 ` James Bottomley
2013-12-19 15:03 ` [PATCH 18/38] ia64: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 19/38] net: atm: " Levente Kurusa
2013-12-27 17:40 ` David Miller
2013-12-19 15:03 ` [PATCH 20/38] net: iucv: " Levente Kurusa
2013-12-27 17:41 ` David Miller
2013-12-19 15:03 ` [PATCH 21/38] workqueue: " Levente Kurusa
2013-12-19 15:20 ` Tejun Heo
2013-12-19 15:31 ` Levente Kurusa
2013-12-19 15:34 ` Tejun Heo
2013-12-19 15:42 ` Levente Kurusa [this message]
2013-12-19 15:45 ` Tejun Heo
2013-12-19 15:03 ` [PATCH 22/38] sound: ac97: " Levente Kurusa
2013-12-19 16:17 ` Takashi Iwai
2013-12-19 15:03 ` [PATCH 23/38] sound: soc: " Levente Kurusa
2013-12-21 14:31 ` Mark Brown
2013-12-19 15:03 ` [PATCH 24/38] pcmcia: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 25/38] pnp: card: " Levente Kurusa
2014-01-05 22:04 ` Rafael J. Wysocki
2013-12-19 15:03 ` [PATCH 26/38] xen: xenbus: " Levente Kurusa
2014-01-02 13:53 ` [Xen-devel] " David Vrabel
2014-01-06 10:00 ` Ian Campbell
2014-01-06 11:00 ` David Vrabel
2014-01-06 11:09 ` Ian Campbell
2013-12-19 15:03 ` [PATCH 27/38] superhyway: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 28/38] superhyway: intc: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 29/38] superhyway: maple: " Levente Kurusa
2013-12-19 15:03 ` [PATCH 30/38] vlynq: " Levente Kurusa
2013-12-19 17:37 ` Florian Fainelli
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