From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bee.tesarici.cz (bee.tesarici.cz [77.93.223.253]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 836335661 for ; Thu, 20 Apr 2023 11:51:33 +0000 (UTC) Received: from meshulam.tesarici.cz (dynamic-2a00-1028-83b8-1e7a-4427-cc85-6706-c595.ipv6.o2.cz [IPv6:2a00:1028:83b8:1e7a:4427:cc85:6706:c595]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by bee.tesarici.cz (Postfix) with ESMTPSA id 6454415DE30; Thu, 20 Apr 2023 13:51:25 +0200 (CEST) Authentication-Results: mail.tesarici.cz; dmarc=fail (p=none dis=none) header.from=tesarici.cz DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=tesarici.cz; s=mail; t=1681991485; bh=g2Y0JUrOOrjs89t94MuNQTvVybtijGZMJ0i55bADfpc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=QjgJpIvhA5OvUg+LBiSm+buLfpgqbqDLvPEbn+iWZH53NDG4alePmDkpKoqDgsZjc 7VcoU6SBCdvY3UJTzYjGnvCcTLvE16JQ4L81toBZSWenxzuaRWHWfYTREtDjWVCQC0 kZAnxudb59X/0NiOz4o7CZLHMFfFY025kmMtDvsOhm6bSqDfR0U9V34RWajnQvdIir r7SRIfoysRlocdJ6IAelLMIOQRFvbt444nfABSY9cD86HMj0MVtg+KVHUj4usw+bVQ 2FAhzCR7ABxYIRz6LNf/OLIjDLC0RNFjT24B09YDOiHEIayUPoHcq69eTOPyq3anlP S+Htq3rPP/m3Q== Date: Thu, 20 Apr 2023 13:51:24 +0200 From: Petr =?UTF-8?B?VGVzYcWZw61r?= To: Alexander Graf Cc: Isaac Manjarres , Catalin Marinas , Robin Murphy , Linus Torvalds , Arnd Bergmann , Greg Kroah-Hartman , Will Deacon , Marc Zyngier , Andrew Morton , Herbert Xu , Ard Biesheuvel , Saravana Kannan , Alasdair Kergon , Daniel Vetter , Joerg Roedel , Mark Brown , Mike Snitzer , "Rafael J. Wysocki" , linux-mm@kvack.org, iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Christoph Hellwig Subject: Re: [PATCH v3 13/13] dma: arm64: Add CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC and enable it for arm64 Message-ID: <20230420135124.62c452db@meshulam.tesarici.cz> In-Reply-To: <629d62ce-b993-35fe-05ff-ee0befc0c73d@csgraf.de> References: <20221106220143.2129263-1-catalin.marinas@arm.com> <20221106220143.2129263-14-catalin.marinas@arm.com> <6e846f75-b330-9523-4356-41d5f9e48f12@arm.com> <20221108100331.GA31944@lst.de> <629d62ce-b993-35fe-05ff-ee0befc0c73d@csgraf.de> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.37; x86_64-suse-linux-gnu) Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Hi Alex! Nice to meet you again... On Thu, 1 Dec 2022 00:32:07 +0100 Alexander Graf wrote: > Hi Isaac, > > On 30.11.22 19:48, Isaac Manjarres wrote: > > On Tue, Nov 08, 2022 at 11:03:31AM +0100, Christoph Hellwig wrote: > >> On Tue, Nov 08, 2022 at 09:52:15AM +0000, Catalin Marinas wrote: > >>> Since it's hard to guess the optimal swiotlb buffer for such platforms, > >>> I think a follow-up step would be to use the DMA coherent pool for > >>> bouncing if no swiotlb buffer is available. At least the pool can grow > >>> dynamically. Yet another option would be to increase the swiotlb buffer > >>> at run-time but it has an overhead for is_swiotlb_buffer(). > >> Alex said he wanted to look into growing the swiotlb buffer on demand > >> for other reason, so adding him to Cc to check if there has been any > >> progress on that. > > Hi Alex, > > > > Did you get a chance to look into this? If so, have you been able to > > make progress on being able to grow the SWIOTLB buffer on demand? > > > I've been slightly under water and haven't been able to look at this yet > :). It's on my list, but will probably be a while until I get to it. > Would you be interested in having a first try? All right, I have just found this thread now after having sent my own patch series to make SWIOTLB dynamic. I hope you don't mind. I didn't want to "steal" the project from you. Petr T