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Date:   Wed, 23 Jun 2021 12:48:12 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Matteo Croce <mcroce@linux.microsoft.com>
Cc:     linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Jens Axboe <axboe@kernel.dk>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v3 1/6] block: add disk sequence number
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On Wed, Jun 23, 2021 at 12:58:53PM +0200, Matteo Croce wrote:
> +void inc_diskseq(struct gendisk *disk)
> +{
> +	static atomic64_t diskseq;

Please don't hide file scope variables in functions.

Can you explain a little more why we need a global sequence count vs
a per-disk one here?