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Date: Tue, 4 Aug 2026 15:25:27 +0200
From: Christoph Hellwig <hch@lst.de>
To: Jan Kara <jack@suse.cz>
Cc: Yu Kuai <yukuai@kernel.org>, Jens Axboe <axboe@kernel.dk>,
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Subject: Re: [RFC PATCH v1 1/3] blk-cgroup: add helpers for bio cgroup state
Message-ID: <20260804132527.GA8078@lst.de>
References: <20260804065313.2092022-1-yukuai@kernel.org> <20260804065313.2092022-2-yukuai@kernel.org> <prx5s4rwbgoeh7wtgyo7vwydh5iwqn6qc2utamowirsplspfmp@e3eteq5xwuyf>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Tue, Aug 04, 2026 at 12:52:16PM +0200, Jan Kara wrote:
> Mostly looks good. Just I think bio_blkcg() should gracefully handle the
> case where bio->bi_blkg is NULL (and return NULL in that case). That way
> you can also get rid of somewhat odd pattern:
> 
> 	if (!bio_blkg(bio))
> 		return ...;
> 	do something with bio_blkcg(bio)
> 
> You can then just check bio_blkcg(bio) directly which is much more obvious.

Yes.  Looking at the whole series I'm also not sure that this makes too
much sense as a split out patch as the next one touches more than half
of the callsite anyway.