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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A43D1C2BA19 for ; Wed, 15 Apr 2020 15:54:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7BEAB208E4 for ; Wed, 15 Apr 2020 15:54:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586966056; bh=vnmTaBMnbWeZwBEDn7jEJ2FxWVO9YscBRgyo6TVC4A8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Db97ULnvfRiFxl7dSPXTPkUlwWMtSHpSiqcnEFOEtxQCrUMMFBpMIMQH23tudrS0z rSRmoqQanfgGmrl4L594bbMAYvRSziRo9u8DyeOWzVqV9GGZFEKDVYd4+zCPST7SJy UKAZ2SitE7kFGyxl4dgFeQE4oxe7TgdWVUi8YgVg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1414942AbgDOPyP (ORCPT ); Wed, 15 Apr 2020 11:54:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:47064 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1414941AbgDOPyN (ORCPT ); Wed, 15 Apr 2020 11:54:13 -0400 Received: from localhost (unknown [106.201.106.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DC99E2078B; Wed, 15 Apr 2020 15:54:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586966052; bh=vnmTaBMnbWeZwBEDn7jEJ2FxWVO9YscBRgyo6TVC4A8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nT/1/zngd0WdQg2V/NRBkL8bMFXf+XI/Vnkjec7wJ3QbxNPL/tpLPpOp3qpNtpypf 4HMA3PKkSUaBIwFssoHqn2gJn3hwtAvlZG3ZikkrwSx7x6+rIJbcyr7FqaopArJPOK MNy0CD4ADSnA4o5FU6R1bkvHhki0V0UPPs1IK6Cc= Date: Wed, 15 Apr 2020 21:23:59 +0530 From: Vinod Koul To: leonid.ravich@dell.com Cc: dmaengine@vger.kernel.org, lravich@gmail.com, Dan Williams , Dave Jiang , Greg Kroah-Hartman , Alexios Zavras , "Alexander.Barabash@dell.com" , Thomas Gleixner , Kate Stewart , Jilayne Lovejoy , Logan Gunthorpe , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] dmaengine: ioat: Decreasing allocation chunk size 2M -> 512K Message-ID: <20200415155359.GT72691@vkoul-mobl> References: <20200402092725.15121-2-leonid.ravich@dell.com> <20200402163356.9029-1-leonid.ravich@dell.com> <20200402163356.9029-2-leonid.ravich@dell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200402163356.9029-2-leonid.ravich@dell.com> Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 02-04-20, 19:33, leonid.ravich@dell.com wrote: > From: Leonid Ravich > > current IOAT driver using big (2MB) allocations chunk for its descriptors > therefore each ioat dma engine need 2 such chunks > (64k entres in ring each entry 64B = 4MB) > requiring 2 * 2M * dmaengine contiguies memory chunk > might fail due to memory fragmention. This is quite decent explanation :) pls use upto 72 chars to make it a better read. > > so we decreasing chunk size and using more chunks. > > Acked-by: Dave Jiang > Signed-off-by: Leonid Ravich > --- > drivers/dma/ioat/dma.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h > index 5216c6b..e6b622e 100644 > --- a/drivers/dma/ioat/dma.h > +++ b/drivers/dma/ioat/dma.h > @@ -83,7 +83,7 @@ struct ioatdma_device { > > #define IOAT_MAX_ORDER 16 > #define IOAT_MAX_DESCS (1 << IOAT_MAX_ORDER) > -#define IOAT_CHUNK_SIZE (SZ_2M) > +#define IOAT_CHUNK_SIZE (SZ_512K) > #define IOAT_DESCS_PER_CHUNK (IOAT_CHUNK_SIZE / IOAT_DESC_SZ) > > struct ioat_descs { > -- > 1.9.3 -- ~Vinod