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Date: Thu, 29 Jun 2023 07:12:38 +0200
From: Christoph Hellwig <hch@lst.de>
To: Petr =?utf-8?B?VGVzYcWZw61r?= <petr@tesarici.cz>
Cc: Petr Tesarik <petrtesarik@huaweicloud.com>,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>,
	"open list:DMA MAPPING HELPERS" <iommu@lists.linux.dev>,
	open list <linux-kernel@vger.kernel.org>,
	Roberto Sassu <roberto.sassu@huaweicloud.com>,
	Kefeng Wang <wangkefeng.wang@huawei.com>
Subject: Re: [PATCH v1 0/2] swiotlb: Fix a couple of bugs in sizing areas
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References: <cover.1687784289.git.petr.tesarik.ext@huawei.com> <20230626160725.5164ca74@meshulam.tesarici.cz>
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On Mon, Jun 26, 2023 at 04:07:25PM +0200, Petr Tesařík wrote:
> As an aside (and not directly related to the bugfixes themselves), I
> wonder why the area size cannot be always equal to IO_TLB_SEGSIZE. Of
> course, we would (usually) end up with more areas, but that should be
> a good thing, shouldn't it? The area structure is quite small, so it
> cannot be because of memory consumption concerns. The overhead of
> taking an uncontended spinlock should also be negligible.

What would be the benefit of this?