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Date: Tue, 22 Apr 2025 09:00:27 +0200
From: Christoph Hellwig <hch@lst.de>
To: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, Nilay Shroff <nilay@linux.ibm.com>,
	Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>,
	Thomas =?iso-8859-1?Q?Hellstr=F6m?= <thomas.hellstrom@linux.intel.com>
Subject: Re: [PATCH V2 03/20] block: don't call freeze queue in
 elevator_switch() and elevator_disable()
Message-ID: <20250422070027.GA30990@lst.de>
References: <20250418163708.442085-1-ming.lei@redhat.com> <20250418163708.442085-4-ming.lei@redhat.com> <20250421123456.GC24038@lst.de> <aAcUbMjt7QdBx3eS@fedora>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Tue, Apr 22, 2025 at 12:00:44PM +0800, Ming Lei wrote:
> On Mon, Apr 21, 2025 at 02:34:56PM +0200, Christoph Hellwig wrote:
> > On Sat, Apr 19, 2025 at 12:36:44AM +0800, Ming Lei wrote:
> > > Both elevator_switch() and elevator_disable() are called from sysfs
> > > store and updating nr_hw_queue code paths only.
> > 
> > I don't understand this sentence.  What does
> > "and updating nr_hw_queue code paths only" mean?
> 
> Both two are only called from the two code paths, in which queue is
> guaranteed to be frozen.

Yes, that's also verified by the asserts.  But the commit message doesn't
sound like that at all.