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Date: Sat, 2 Jan 2016 02:31:06 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Zhihui Zhang <zzhsuny@gmail.com>
Cc: clm@fb.com, tytso@mit.edu, swhiteho@redhat.com, mfasheh@suse.com,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] Remove I_WILL_FREE
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On Fri, Jan 01, 2016 at 08:52:06PM -0500, Zhihui Zhang wrote:
> I_WILL_FREE does not really add any new functionality over I_FREEING.
> If I_WILL_FREE is set, it will be replaced by I_FREEING under the inode
> lock. And they always appear in the same if statement.

Do they?  Consider

fs/fs-writeback.c:351:  if (unlikely(inode->i_state & I_FREEING))
fs/fs-writeback.c:472:  if (inode->i_state & (I_WB_SWITCH | I_FREEING) ||
fs/fs-writeback.c:1161: if (inode->i_state & I_FREEING)
fs/fs-writeback.c:2049:         if (inode->i_state & I_FREEING)

for a few counterexamples...