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Date: Mon, 1 Jun 2026 09:11:13 +0200
From: Christoph Hellwig <hch@lst.de>
To: Bart Van Assche <bvanassche@acm.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
	Jens Axboe <axboe@kernel.dk>,
	linux-block <linux-block@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Ming Lei <tom.leiming@gmail.com>,
	Damien Le Moal <dlemoal@kernel.org>, Christoph Hellwig <hch@lst.de>,
	Qu Wenruo <wqu@suse.com>, Hillf Danton <hdanton@sina.com>
Subject: Re: [PATCH] block: assign caller-specific lockdep class to
 disk->open_mutex
Message-ID: <20260601071113.GB7468@lst.de>
References: <147ed056-03d9-4214-b925-0f10fc00cf27@I-love.SAKURA.ne.jp> <4cf7ecc7-932c-4589-9d0f-3e025e83e27c@acm.org>
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On Sat, May 30, 2026 at 02:15:04PM -0700, Bart Van Assche wrote:
> On 5/30/26 6:45 AM, Tetsuo Handa wrote:
>> -	static struct lock_class_key __key;				\
>> +	static struct lock_class_key __key[2];				\
> The two elements of this array have different roles. From the point of
> view of code readability and maintainability it's probably much better
> to make this a struct with two named members rather than a two-element
> array.

Exactly.