From patchwork Thu Jun 25 07:43:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song Bao Hua (Barry Song)" X-Patchwork-Id: 11624719 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B44C514F6 for ; Thu, 25 Jun 2020 07:47:29 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8DD1920675 for ; Thu, 25 Jun 2020 07:47:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="m57q9sTa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DD1920675 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hisilicon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=xMqc/O/xDEkXKHW548WwAynwLAS7ia7i/UJ+Cry2+II=; b=m57q9sTa60Mlrq7S8udf2EUN+j OlWy5rm1Hh40lg/I7Tc+kyKm+MgM4tMEIrRfDBVROpSSVyrN4knUK0p7Gw2r6CKNHhByoSW65oc5F aqQ971sNjVepTlLg+NcS2LCHvZmErL9Je63NTg3L1pXHC++jyNYBFCftGZD+XMVP22IIe26YScnwW gIkupUTz7TvOviw3bPL9ZfamrmDzBg2YGDCm1mmlcw6DkxtfMPoEAXOg+5AhrXmI2rln0VLMvjP3/ JB1sV09cscvQeizyoOXFsq/jGKZpKr52+fMX5P26jRVKPfH9qFjgmRGyb0UY26oWVrcM7fuad4JFz CYSHJa+A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1joMZq-0005kd-S1; Thu, 25 Jun 2020 07:45:42 +0000 Received: from szxga06-in.huawei.com ([45.249.212.32] helo=huawei.com) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1joMZi-0005ed-K3 for linux-arm-kernel@lists.infradead.org; Thu, 25 Jun 2020 07:45:36 +0000 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id A5FAE6BBC17D19E99093; Thu, 25 Jun 2020 15:45:23 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.203.118) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.487.0; Thu, 25 Jun 2020 15:45:15 +0800 From: Barry Song To: , , , , , Subject: [PATCH v2 0/2] make dma_alloc_coherent NUMA-aware by per-NUMA CMA Date: Thu, 25 Jun 2020 19:43:28 +1200 Message-ID: <20200625074330.13668-1-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 MIME-Version: 1.0 X-Originating-IP: [10.126.203.118] X-CFilter-Loop: Reflected X-Spam-Note: CRM114 invocation failed X-Spam-Score: 0.7 (/) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (0.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.32 listed in list.dnswl.org] 0.0 RCVD_IN_MSPIKE_H4 RBL: Very Good reputation (+4) [45.249.212.32 listed in wl.mailspike.net] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 SPF_HELO_PASS SPF: HELO matches SPF record 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders 3.0 AC_FROM_MANY_DOTS Multiple periods in From user name X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Barry Song , iommu@lists.linux-foundation.org, linuxarm@huawei.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Ganapatrao Kulkarni has put some effort on making arm-smmu-v3 use local memory to save command queues[1]. I also did similar job in patch "iommu/arm-smmu-v3: allocate the memory of queues in local numa node" [2] while not realizing Ganapatrao did that before. But it seems it is much better to make dma_alloc_coherent() to be inherently NUMA-aware on NUMA-capable systems. Right now, smmu is using dma_alloc_coherent() to get memory to save queues and tables. Typically, on ARM64 server, there is a default CMA located at node0, which could be far away from node2, node3 etc. Saving queues and tables remotely will increase the latency of ARM SMMU significantly. For example, when SMMU is at node2 and the default global CMA is at node0, after sending a CMD_SYNC in an empty command queue, we have to wait more than 550ns for the completion of the command CMD_SYNC. However, if we save them locally, we only need to wait for 240ns. with per-numa CMA, smmu will get memory from local numa node to save command queues and page tables. that means dma_unmap latency will be shrunk much. Meanwhile, when iommu.passthrough is on, device drivers which call dma_ alloc_coherent() will also get local memory and avoid the travel between numa nodes. [1] https://lists.linuxfoundation.org/pipermail/iommu/2017-October/024455.html [2] https://www.spinics.net/lists/iommu/msg44767.html -v2: fix some issues reported by kernel test robot; fallback to default cma to avoid regression while allocation fails in per-numa cma according to Jonathan Cameron's suggestion; free memory properly Barry Song (2): dma-direct: provide the ability to reserve per-numa CMA arm64: mm: reserve per-numa CMA after numa_init arch/arm64/mm/init.c | 2 + include/linux/dma-contiguous.h | 4 ++ kernel/dma/Kconfig | 10 ++++ kernel/dma/contiguous.c | 99 ++++++++++++++++++++++++++++++---- 4 files changed, 106 insertions(+), 9 deletions(-)