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Date: Thu, 29 May 2014 17:53:51 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Miklos Szeredi <mszeredi@suse.cz>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: fs/dcache.c - BUG: soft lockup - CPU#5 stuck for 22s!
 [systemd-udevd:1667]
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On Thu, May 29, 2014 at 09:29:42AM -0700, Linus Torvalds wrote:
> On Thu, May 29, 2014 at 9:23 AM, Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> > BTW, lock_parent() might be better off if in contended case it would not
> > bother with rename_lock and did something like this:
> > again:
> 
> Ack. I think that's much better.

Pushed to #for-linus (with dumb braino fixed - it's if (parent != dentry),
not if (parent)).  I'll wait with folding it back into the commit that
introduces lock_parent() until we get testing results...