From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH repost] sched: export sched_set/getaffinity to modules
Date: Mon, 26 Jul 2010 22:55:23 +0300
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Cc: Sridhar Samudrala <sri@us.ibm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Tejun Heo <tj@kernel.org>, Ingo Molnar <mingo@elte.hu>,
	netdev <netdev@vger.kernel.org>,
	lkml <linux-kernel@vger.kernel.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Dmitri Vorobiev <dmitri.vorobiev@movial.com>,
	Jiri Kosina <jkosina@suse.cz>,
	Thomas Gleixner <tglx@linutronix.de>,
	Andi Kleen <ak@linux.intel.com>
To: Oleg Nesterov <oleg@redhat.com>
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On Mon, Jul 26, 2010 at 08:08:34PM +0200, Oleg Nesterov wrote:
> On 07/26, Sridhar Samudrala wrote:
> >
> > I have been testing out a similar patch that uses kernel_thread() without CLONE_FILES
> > flag rather than create_kthread() and then closing the files.
> 
> !CLONE_FILES can't help. copy_files() does dup_fd() in this case.
> The child still inherits the files.
> 
> > Either version should be fine.
> 
> I think neither version is fine ;)
> 
> exit_files() is not enough too. How about the signals,

As I said, signals are unimportant as we are using this
thread to base a worker on - it sleeps uninterruptibly.

> reparenting?

That's actually a feature: it lets us find out which process
owns the device using the thread by looking at the parent.

> 
> I already forgot all details, probably I missed somethig. But it
> seems to me that it is better to just export get/set affinity and
> forget about all complications.
> 
> Oleg.