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Date:   Thu, 30 Jan 2020 05:41:15 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Nikolay Borisov <nborisov@suse.com>
Cc:     linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 1/2] btrfs: Implement DRW lock
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On Thu, Jan 30, 2020 at 02:59:41PM +0200, Nikolay Borisov wrote:
> A (D)ouble (R)eader (W)riter lock is a locking primitive that allows
> to have multiple readers or multiple writers but not multiple readers
> and writers holding it concurrently. The code is factored out from
> the existing open-coded locking scheme used to exclude pending
> snapshots from nocow writers and vice-versa. Current implementation
> actually favors Readers (that is snapshot creaters) to writers (nocow
> writers of the filesystem).

Any reason not to move it to lib/ under a new option so that other
users could reuse it as needed?