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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 22 Aug 2018 13:14:51 -0700
Message-ID: <CA+55aFzMv5rkRJs2Xu4L3aAQM6UWSAFhHJhXECyquaW4+BXwBQ@mail.gmail.com>
Subject: Re: [PATCH] ovl: set I_CREATING on inode being created
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        linux-unionfs@vger.kernel.org, Al Viro <viro@zeniv.linux.org.uk>
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On Wed, Aug 22, 2018 at 12:58 PM Miklos Szeredi <miklos@szeredi.hu> wrote:
>
> > So I'd like some clarification on this point before applying it. It's
> > possible that the spinlock is required, I just want to understand why.
>
> I added the spinlock, because it's cheap (new_inode() already pulls it
> into L1 cache) and because it's much harder to prove that lockless one
> is correct than just adding that locking.

Ok, thanks, looks good to me. And looking around, I think it matches
most of the other cases of us setting those I_NEW and I_CREATING
flags, so I guess it's good from a consistency standpoint too.

I just wanted that clarified, but I'll just apply the patch directly.

Thanks,

             Linus