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	Tue, 08 Oct 2024 05:01:11 +0000
Date: Mon, 7 Oct 2024 22:01:11 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Yu Kuai <yukuai1@huaweicloud.com>
Cc: Tejun Heo <tj@kernel.org>, axboe@kernel.dk, josef@toxicpanda.com,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	cgroups@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com,
	"yukuai (C)" <yukuai3@huawei.com>
Subject: Re: [PATCH v2 1/5] blk-cgroup: add a new helper blkg_print_dev_name()
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On Tue, Oct 08, 2024 at 09:39:05AM +0800, Yu Kuai wrote:
> Hi,
> 
> 在 2024/10/01 1:11, Tejun Heo 写道:
> > Hello,
> > 
> > On Mon, Sep 30, 2024 at 04:52:58PM +0800, Yu Kuai wrote:
> > > +static inline bool blkg_print_dev_name(struct seq_file *sf,
> > > +				       struct blkcg_gq *blkg)
> > > +{
> > > +	struct gendisk *disk = blkg->q->disk;
> > > +
> > > +	if (!disk)
> > > +		return false;
> > > +
> > > +	seq_printf(sf, "%u:%u", disk->major, disk->first_minor);
> > > +	return true;
> > > +}
> > > +
> > 
> > I wonder whether we just should add a name field to disk.
> > 
> 
> Of course we can, however, I'm not sure if this is better, because
> this field is not used in the fast path.

Struct gendisk does have a (disk_)name field aleady.