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Date:   Mon, 15 May 2023 13:35:16 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Peng Zhang <zhangpeng.00@bytedance.com>, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        maple-tree@lists.infradead.org
Subject: Re: [PATCH 02/10] maple_tree: Drop mtree_alloc_{range,rrange}() and
 related functions.
Message-ID: <20230515173516.5tmytjvnzvdogfm7@revolver>
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* Matthew Wilcox <willy@infradead.org> [230515 13:27]:
> On Mon, May 15, 2023 at 09:17:49PM +0800, Peng Zhang wrote:
> > Drop mtree_alloc_{range,rrange}(), mas_{rev_}alloc() and mas_fill_gap().
> > mtree_alloc_{range,rrange}() currently have no users and can be easily
> > implemented with mas_empty_area{_rev}(). mas_{rev_}alloc() and
> > mas_fill_gap() are just their internal functions, drop them together.
> 
> No, I think this is the wrong way to go.
> 
> Most users should not be using the mas_* API.  These are the advanced
> APIs.  Most users will want to use mtree_alloc_range().  Just like most
> users of the XArray use the xa_insert() API rather than open-coding the
> xa_state and calling the xas_* APIs.
> 
> Please read Documentation/core-api/xarray.rst and maple_tree.rst for more
> details on Normal vs Advanced API.  The real problem is that we have so
> few users today, so you haven't seen that most people don't want to use
> the advanced APIs.


Peng, Apologies on the confusion.  Please do as Matthew said.  If you
have a way to unify the functionality to use the same internal
functions, then I think that would be a welcome change.