From: NeilBrown <neil@brown.name>
Subject: Re: [RFC PATCH v1 29/30] fs: track whether the i_version has been queried with an i_state flag
Date: Sat, 04 Mar 2017 11:03:53 +1100
Message-ID: <87wpc5lxg6.fsf@notabene.neil.brown.name>
References: <1482339827-7882-1-git-send-email-jlayton@redhat.com> <1482339827-7882-30-git-send-email-jlayton@redhat.com>
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Cc: linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org,
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To: Jeff Layton <jlayton@redhat.com>, linux-fsdevel@vger.kernel.org
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On Wed, Dec 21 2016, Jeff Layton wrote:

> @@ -2072,7 +2093,12 @@ inode_cmp_iversion(const struct inode *inode, cons=
t u64 old)
>  static inline bool
>  inode_iversion_need_inc(struct inode *inode)
>  {
> -	return true;
> +	bool ret;
> +
> +	spin_lock(&inode->i_lock);
> +	ret =3D inode->i_state & I_VERS_BUMP;
> +	spin_unlock(&inode->i_lock);
> +	return ret;
>  }
>=20=20

I know this code gets removed, so this isn't really important.
By why do you take the spinlock here?  What are you racing again?

Thanks,
NeilBrown

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