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Date: Thu, 5 Sep 2024 10:32:22 -0400
From: Mike Snitzer <snitzer@kernel.org>
To: Eric Biggers <ebiggers@kernel.org>
Cc: dm-devel@lists.linux.dev, Alasdair Kergon <agk@redhat.com>,
	Mikulas Patocka <mpatocka@redhat.com>, Tejun Heo <tj@kernel.org>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	Sami Tolvanen <samitolvanen@google.com>
Subject: Re: dm verity: don't use WQ_MEM_RECLAIM
Message-ID: <ZtnA9gSNLnJXvA9z@kernel.org>
References: <20240904040444.56070-1-ebiggers@kernel.org>
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In-Reply-To: <20240904040444.56070-1-ebiggers@kernel.org>

On Tue, Sep 03, 2024 at 09:04:44PM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@google.com>
> 
> Since dm-verity doesn't support writes, the kernel's memory reclaim code
> will never wait on dm-verity work.  That makes the use of WQ_MEM_RECLAIM
> in dm-verity unnecessary.  WQ_MEM_RECLAIM has been present from the
> beginning of dm-verity, but I could not find a justification for it;
> I suspect it was just copied from dm-crypt which does support writes.
> 
> Therefore, remove WQ_MEM_RECLAIM from dm-verity.  This eliminates the
> creation of an unnecessary rescuer thread per dm-verity device.
> 
> Signed-off-by: Eric Biggers <ebiggers@google.com>

Thanks!

Reviewed-by: Mike Snitzer <snitzer@kernel.org>