From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A7F3AC433EF for ; Tue, 30 Nov 2021 14:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Message-ID:Date:References: In-reply-to:Content-transfer-encoding:Content-type:MIME-Version:Subject:From: cc:To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=BZYi9ht2xy65JyC43IPolVUMbyaxhCW/7gh9Gp9ztQE=; b=atDzUsXXhYQkhF+4oMLE1SQnEu /fFNrf7b57C+El1a74Ek16Owo3R6FW6yZhm1s1QQk4emtfyn1PnrY0jQjq2XZ8zLuQNOkHMNt5AKr hNNV//SsJSR15fsj/caD28mvoVM/gD9FpJXDWQ6kj0BD179D0fOjwZuMJ9bVtQJxVYV7ZjDYPsnkv y9ulXZNYuwlngoF2uR650UXTVhop0H0Q0LkCl72YKwQjY33R8CpmNhwHfbubYf8x+mKrnT26QJdVi +bRfPnIUpxRk2Io4Eujw18RHLNs1rDOnZgRpPw6xrC1vqjzOKmajEo0p+gIjxc9dGoalRk6iI296s cpwXBwwg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ms4P1-005fMV-18; Tue, 30 Nov 2021 14:46:39 +0000 Received: from phobos.denx.de ([85.214.62.61]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ms4Ow-005fLR-I0 for linux-nvme@lists.infradead.org; Tue, 30 Nov 2021 14:46:36 +0000 Received: from janitor.denx.de (unknown [62.91.23.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: noc@denx.de) by phobos.denx.de (Postfix) with ESMTPSA id 48F3780934 for ; Tue, 30 Nov 2021 15:46:31 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=phobos-20191101; t=1638283591; bh=BZYi9ht2xy65JyC43IPolVUMbyaxhCW/7gh9Gp9ztQE=; h=To:cc:From:Subject:In-reply-to:References:Date:From; b=GNoFB6LYCzJk67puZ34YgP0GzMEsxMhk/KY5AjDS0CotVlfCu4Eu4JdMWtQZwjY4h WxuOOAKoARYScACMJ/yBmSBv1upv7va/zcoqsN7Ybms4N/flq1yVLZNYr3zjxscK7k uOtzHGZg89PXXrIUBEOYJ/xQche+e6DT+7kq6BRHii3muXAd1GeWRzu62LyZE2XBea s3yr+zQFAhXTYJfFaA8mfa6j3IN0rlT91N31UtTDTVetMxnSBhQOlQibvMPHkgohno AKlO9uTMBrvYoWCj/p9qSFZfQMX+/HcGhO9Q2WI32tFMAdo7QKYybRPqph/n1JrmR5 /rZh8ilCjaTNw== Received: by janitor.denx.de (Postfix, from userid 108) id B8987A0254; Tue, 30 Nov 2021 15:46:30 +0100 (CET) Received: from gemini.denx.de (gemini.denx.de [10.4.0.2]) by janitor.denx.de (Postfix) with ESMTPS id 8D5B6A00AA; Tue, 30 Nov 2021 15:46:25 +0100 (CET) Received: from gemini.denx.de (localhost [IPv6:::1]) by gemini.denx.de (Postfix) with ESMTP id 253191E0BCB; Tue, 30 Nov 2021 15:46:25 +0100 (CET) To: Paul Menzel cc: linux-raid@vger.kernel.org, LKML , linux-accelerators@lists.ozlabs.org, linux-nvme@lists.infradead.org From: Wolfgang Denk Subject: Re: Using aGPU for RAID calculations (proprietary GRAID SupremeRAID) MIME-Version: 1.0 Content-type: text/plain; charset=UTF-8 Content-transfer-encoding: 8bit In-reply-to: References: Comments: In-reply-to Paul Menzel message dated "Tue, 30 Nov 2021 12:58:10 +0100." Date: Tue, 30 Nov 2021 15:46:25 +0100 Message-ID: <3846571.1638283585@gemini.denx.de> X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211130_064634_787199_BD127112 X-CRM114-Status: GOOD ( 22.77 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org Dear Paul, In message you wrote: > > I read about GRAID SupremeRAID [1], which seems to be an Nvidia T1000 > card and software to use the card for RAID calculations. I doubt this is an efficient way. The (IMHO) most efficient solution I have seen so far was the AMCC PPC440SPe Power Architecture processors. These we able to calculate the needed parity information on the fly in the DMA controller while writing the data to disk. > Does the Linux kernel already have an API to offload calculations to > accelerator cards, so it’s basically plug and play (with AMD graphics > cards for example using HSA/KFD)? Entropy sources, like the ChaosKey > [3], work like that. If not, would the implementation go under `lib/raid6`? We implemented Linux driver support for adma/async_tx/raid6 for this hardware, but that was a long time ago (2008/2009), and I doubt this has been tested recently. But at least some code is still in mainline, see for example arch/powerpc/platforms/44x/ppc440spe_dma_engines.c Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de Another megabytes the dust.