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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,
        Lennart Poettering <lennart@poettering.net>,
        Luca Boccassi <bluca@debian.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Damien Le Moal <damien.lemoal@wdc.com>,
        Tejun Heo <tj@kernel.org>,
        Javier Gonz??lez <javier@javigon.com>,
        Niklas Cassel <niklas.cassel@wdc.com>,
        Johannes Thumshirn <johannes.thumshirn@wdc.com>,
        Hannes Reinecke <hare@suse.de>,
        Matthew Wilcox <willy@infradead.org>,
        Christoph Hellwig <hch@infradead.org>,
        JeffleXu <jefflexu@linux.alibaba.com>
Subject: Re: [PATCH v3 1/6] block: add disk sequence number
Message-ID: <YNMffBWvs/Fz2ptK@infradead.org>
References: <20210623105858.6978-1-mcroce@linux.microsoft.com>
 <20210623105858.6978-2-mcroce@linux.microsoft.com>
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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?