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From:   David Howells <dhowells@redhat.com>
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To:     Matthew Wilcox <willy@infradead.org>
Cc:     dhowells@redhat.com, linux-fsdevel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
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        ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna.schumaker@netapp.com>,
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        Dominique Martinet <asmadeus@codewreck.org>,
        Jeff Layton <jlayton@redhat.com>,
        David Wysochanski <dwysocha@redhat.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 02/30] mm: Add set/end/wait functions for PG_private_2
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Date:   Thu, 08 Apr 2021 16:25:34 +0100
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Matthew Wilcox <willy@infradead.org> wrote:

> > +void end_page_private_2(struct page *page)
> > +{
> > +	page = compound_head(page);
> > +	VM_BUG_ON_PAGE(!PagePrivate2(page), page);
> > +	clear_bit_unlock(PG_private_2, &page->flags);
> > +	wake_up_page_bit(page, PG_private_2);
> 
> ... but when we try to end on a tail, we actually wake up the head ...

Question is, should I remove compound_head() here or add it into the other
functions?

David