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Date:   Mon, 24 Aug 2020 18:36:39 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Jan Kara <jack@suse.cz>
Cc:     linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>,
        William Kucharski <william.kucharski@oracle.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/7] mm: Pass pvec directly to find_get_entries
Message-ID: <20200824173639.GD17456@casper.infradead.org>
References: <20200819150555.31669-1-willy@infradead.org>
 <20200819150555.31669-7-willy@infradead.org>
 <20200824161620.GK24877@quack2.suse.cz>
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On Mon, Aug 24, 2020 at 06:16:20PM +0200, Jan Kara wrote:
> On Wed 19-08-20 16:05:54, Matthew Wilcox (Oracle) wrote:
> > All callers of find_get_entries() use a pvec, so pass it directly
> > instead of manipulating it in the caller.
> > 
> > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> 
> Rather than passing pvec to find_get_entries() and then making everybody
> use it, won't it more consistent WRT the naming to make everybody use
> pagevec_lookup_entries() (which is trivial at this point in the series) and
> then rename find_get_entries() to pagevec_lookup_entries()? I.e., I'd prefer
> if the final function was called pagevec_lookup_entries() because that is
> IMO more consistent with how other functions are named in this area...

It seemed more consistent to me to have everybody using
find_get_entries().  To me the pagevec functions:

1. Are in mm/swap.c (not really sure why)
2. Take pvec as the first argument, not the last
3. Wrap a find_* function

Whereas the find_* functions:

1. Are in mm/filemap.c
2. Take mapping as the first argument
3. Manipulate the XArray directly

We already have functions in filemap which take a pagevec, eg
page_cache_delete_batch() and delete_from_page_cache_batch().

So if we're going to merge the two functions, it seems more natural to
have it in filemap.c and called find_get_entries(), but I'm definitely
open to persuasion on this!