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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 7EBEDC2BA12 for ; Thu, 2 Apr 2020 15:06:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4CD2F206CC for ; Thu, 2 Apr 2020 15:06:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389126AbgDBPGX (ORCPT ); Thu, 2 Apr 2020 11:06:23 -0400 Received: from mga02.intel.com ([134.134.136.20]:46064 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389046AbgDBPGW (ORCPT ); Thu, 2 Apr 2020 11:06:22 -0400 IronPort-SDR: 4D8RU2cY6TDk9aDUSLGUhPGw896w78bSp+k1g3Ld/MFaJwjjZu7DmSqWpn4O2xVprYS7AlpOVl a4IJzJXaE16w== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Apr 2020 08:06:21 -0700 IronPort-SDR: k0nZ9Qd2HT/5yhMfVt502GBN9EOzOQDTwehNxMiHA5YqPY8haqm9eO0q2ZPMWE2LbzRRSsLm3Z 4Dgl2RNI/F9g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,336,1580803200"; d="scan'208";a="284807116" Received: from ccui-mobl1.amr.corp.intel.com (HELO [10.134.85.228]) ([10.134.85.228]) by fmsmga002.fm.intel.com with ESMTP; 02 Apr 2020 08:06:20 -0700 Subject: Re: [PATCH 2/2] dmaengine: ioat: Decreasing allocation chunk size 2M -> 512K To: leonid.ravich@dell.com, dmaengine@vger.kernel.org Cc: lravich@gmail.com, Vinod Koul , Dan Williams , Greg Kroah-Hartman , Alexios Zavras , "Alexander.Barabash@dell.com" , Thomas Gleixner , Kate Stewart , Jilayne Lovejoy , Logan Gunthorpe , linux-kernel@vger.kernel.org References: <20200402092725.15121-1-leonid.ravich@dell.com> <20200402092725.15121-2-leonid.ravich@dell.com> From: Dave Jiang Message-ID: <793bc07b-fec9-27ee-7eff-203326e3608a@intel.com> Date: Thu, 2 Apr 2020 08:06:19 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200402092725.15121-2-leonid.ravich@dell.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 4/2/2020 2:27 AM, 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. > > so we decresging chunk size and using more chunks. decreasing > > Signed-off-by: Leonid Ravich Acked-by: Dave Jiang if the two patches have been tested on hw. > --- > 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 535aba9..e9757bc 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 { >