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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 7493DC433E0 for ; Tue, 2 Jun 2020 04:23:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 472632074B for ; Tue, 2 Jun 2020 04:23:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591071827; bh=KForfwzUUC3Tk8fGSUSDwVHsxPKPlXtsHIFrysGM4iY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=K7/9fhuBd+9qEnK6KsJZURjrNn3H+ylI95pbzcw5QRlcyqKHzH60NqbGlIrBnsLsH ZQPg3mDhNR2a1lCMXCKDxxPTmwytLzeBIoxbqZfzwifM3cYPX8XGT8490uDgqLJzJS g6Fei9KWLuGDiJFexazEXfUFXf8C1hEu3oxFdk6g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726096AbgFBEXq (ORCPT ); Tue, 2 Jun 2020 00:23:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:56474 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725841AbgFBEXq (ORCPT ); Tue, 2 Jun 2020 00:23:46 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 99144206C3; Tue, 2 Jun 2020 04:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591071825; bh=KForfwzUUC3Tk8fGSUSDwVHsxPKPlXtsHIFrysGM4iY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=V45ZYtoL70LH0+jjtU6K2Pm6h5EN5dcw3LAqGkCFEUvGLepwp/RzbDsv1tm9nbE8X IKfw5CNMxoDntLxKInDAvmDaDJ9slDOOgr5WQi4LT/HYwuAb815pAredk+uHwsM3gx Wz/hBz4BIW9vvksL95NAPm/tvL3WM12JokdvE9Lo= Date: Tue, 2 Jun 2020 06:23:40 +0200 From: Greg KH To: Barry Song Cc: rafael@kernel.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linuxarm@huawei.com, Prime Zeng , Robin Murphy Subject: Re: [PATCH] driver core: platform: expose numa_node to users in sysfs Message-ID: <20200602042340.GA2130884@kroah.com> References: <20200602030139.73012-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200602030139.73012-1-song.bao.hua@hisilicon.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 02, 2020 at 03:01:39PM +1200, Barry Song wrote: > For some platform devices like iommu, particually ARM smmu, users may > care about the numa locality. for example, if threads and drivers run > near iommu, they may get much better performance on dma_unmap_sg. > For other platform devices, users may still want to know the hardware > topology. > > Cc: Prime Zeng > Cc: Robin Murphy > Signed-off-by: Barry Song > --- > drivers/base/platform.c | 26 +++++++++++++++++++++++++- > 1 file changed, 25 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index b27d0f6c18c9..7794b9a38d82 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1062,13 +1062,37 @@ static ssize_t driver_override_show(struct device *dev, > } > static DEVICE_ATTR_RW(driver_override); > > +static ssize_t numa_node_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + return sprintf(buf, "%d\n", dev_to_node(dev)); > +} > +static DEVICE_ATTR_RO(numa_node); > + > +static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a, > + int n) > +{ > + struct device *dev = container_of(kobj, typeof(*dev), kobj); > + > + if (a == &dev_attr_numa_node.attr && > + dev_to_node(dev) == NUMA_NO_NODE) > + return 0; > + > + return a->mode; > +} > > static struct attribute *platform_dev_attrs[] = { > &dev_attr_modalias.attr, > + &dev_attr_numa_node.attr, > &dev_attr_driver_override.attr, > NULL, > }; > -ATTRIBUTE_GROUPS(platform_dev); > + > +static struct attribute_group platform_dev_group = { > + .attrs = platform_dev_attrs, > + .is_visible = platform_dev_attrs_visible, > +}; > +__ATTRIBUTE_GROUPS(platform_dev); > > static int platform_uevent(struct device *dev, struct kobj_uevent_env *env) > { Platform devices are NUMA? That's crazy, and feels like a total abuse of platform devices and drivers that really should belong on a "real" bus. What drivers in the kernel today have this issue? thanks, greg k-h