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Date:   Wed, 16 Feb 2022 11:47:00 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Liam Howlett <liam.howlett@oracle.com>
Cc:     "maple-tree@lists.infradead.org" <maple-tree@lists.infradead.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v6 00/71] Introducing the Maple Tree
Message-Id: <20220216114700.f9473d88144dc59fc4d764fb@linux-foundation.org>
In-Reply-To: <20220215143728.3810954-1-Liam.Howlett@oracle.com>
References: <20220215143728.3810954-1-Liam.Howlett@oracle.com>
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On Tue, 15 Feb 2022 14:37:44 +0000 Liam Howlett <liam.howlett@oracle.com> wrote:

> The maple tree is an RCU-safe range based B-tree designed to use modern
> processor cache efficiently.  There are a number of places in the kernel
> that a non-overlapping range-based tree would be beneficial, especially
> one with a simple interface.  The first user that is covered in this
> patch set is the vm_area_struct, where three data structures are
> replaced by the maple tree: the augmented rbtree, the vma cache, and the
> linked list of VMAs in the mm_struct.  The long term goal is to reduce
> or remove the mmap_sem contention.

Has a path been chosen which gets us from here to significant reduction
in mmap_lock overhead?

If so, what's the plan and what must be done?

Thanks.