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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 D5A2FC48BE8 for ; Wed, 16 Jun 2021 15:23:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B011B6128B for ; Wed, 16 Jun 2021 15:23:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234598AbhFPPZw (ORCPT ); Wed, 16 Jun 2021 11:25:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:47342 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234589AbhFPPZv (ORCPT ); Wed, 16 Jun 2021 11:25:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0E7196135C; Wed, 16 Jun 2021 15:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623857025; bh=P9kMQ2jD1IPtWm/U0GmUTuT+zZSu3WntBzFULA8XsKs=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=Klm5REesq4KWd2XEmOVEITrGliAxe44pUkUfIKAC4nsSCFZ0ktmXvJtcDd2K5biyr cci0H4xIP403/1NFLY7WOnf2Civf62LtOb0zt1osOj22vWzZDKrFRRPgu/GjYD6s0s R0uAJR/2dWKVv6ENcztuZDPByuviPG+gS2Er9WlhOeL3zqPWnGX8dxm7shgXx0ZUEh uHyHNyevBsM681rYqUHX2rzFtYqTQ3K6WnkNvmvxjUH0yMHMdBFZQN1M3YGFrONv4K 6fqLXBFAJy+82iZfxJknssnMXDJ0GA+9u4zAdd6Si+yljlNzb7yq9Jjw1DkWF1Tm8a UUOIYjeeJoeWA== Date: Wed, 16 Jun 2021 10:23:43 -0500 From: Bjorn Helgaas To: "liuqi (BA)" Cc: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Linuxarm , will@kernel.org, mark.rutland@arm.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, zhangshaokun@hisilicon.com Subject: Re: [PATCH v6 2/2] drivers/perf: hisi: Add driver for HiSilicon PCIe PMU Message-ID: <20210616152343.GA2977964@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 16, 2021 at 09:09:40AM +0800, liuqi (BA) wrote: > On 2021/6/12 7:33, Krzysztof Wilczyński wrote: > > > +static ssize_t hisi_pcie_event_sysfs_show(struct device *dev, > > > + struct device_attribute *attr, char *buf) > > > +{ > > > + struct dev_ext_attribute *eattr; > > > + > > > + eattr = container_of(attr, struct dev_ext_attribute, attr); > > > + > > > + return sysfs_emit(buf, "config=0x%lx\n", (unsigned long)eattr->var); > > > +} > > > > I am not that familiar with the perf drivers, thus I might be completely > > wrong here, but usually for sysfs objects a single value is preferred, > > so that this "config=" technically would not be needed, unless this is > > somewhat essential to the consumers of this attribute to know what the > > value is?  What do you think? > > "config=" is a supported for userspace tool, it is a kind of alias, so > cannot be remover here, thanks. I don't understand this part. This is brand-new functionality for the kernel, so there's no requirement to maintain compatibility for existing userspace tools. If there's a similar sysfs show function for other perf drivers, and you need to be compatible with *that*, fine. But if this is merely about being compatible with userspace that uses out-of-tree kernel functionality, that's not a real factor. Bjorn 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=-4.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 8EC63C48BE6 for ; Wed, 16 Jun 2021 15:25:26 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 5C04C6128B for ; Wed, 16 Jun 2021 15:25:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5C04C6128B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; 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Wed, 16 Jun 2021 15:23:57 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltXOL-006rn1-Nl for linux-arm-kernel@lists.infradead.org; Wed, 16 Jun 2021 15:23:47 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0E7196135C; Wed, 16 Jun 2021 15:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623857025; bh=P9kMQ2jD1IPtWm/U0GmUTuT+zZSu3WntBzFULA8XsKs=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=Klm5REesq4KWd2XEmOVEITrGliAxe44pUkUfIKAC4nsSCFZ0ktmXvJtcDd2K5biyr cci0H4xIP403/1NFLY7WOnf2Civf62LtOb0zt1osOj22vWzZDKrFRRPgu/GjYD6s0s R0uAJR/2dWKVv6ENcztuZDPByuviPG+gS2Er9WlhOeL3zqPWnGX8dxm7shgXx0ZUEh uHyHNyevBsM681rYqUHX2rzFtYqTQ3K6WnkNvmvxjUH0yMHMdBFZQN1M3YGFrONv4K 6fqLXBFAJy+82iZfxJknssnMXDJ0GA+9u4zAdd6Si+yljlNzb7yq9Jjw1DkWF1Tm8a UUOIYjeeJoeWA== Date: Wed, 16 Jun 2021 10:23:43 -0500 From: Bjorn Helgaas To: "liuqi (BA)" Cc: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Linuxarm , will@kernel.org, mark.rutland@arm.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, zhangshaokun@hisilicon.com Subject: Re: [PATCH v6 2/2] drivers/perf: hisi: Add driver for HiSilicon PCIe PMU Message-ID: <20210616152343.GA2977964@bjorn-Precision-5520> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210616_082345_848812_B5C076C1 X-CRM114-Status: GOOD ( 17.87 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gV2VkLCBKdW4gMTYsIDIwMjEgYXQgMDk6MDk6NDBBTSArMDgwMCwgbGl1cWkgKEJBKSB3cm90 ZToKPiBPbiAyMDIxLzYvMTIgNzozMywgS3J6eXN6dG9mIFdpbGN6ecWEc2tpIHdyb3RlOgoKPiA+ ID4gK3N0YXRpYyBzc2l6ZV90IGhpc2lfcGNpZV9ldmVudF9zeXNmc19zaG93KHN0cnVjdCBkZXZp Y2UgKmRldiwKPiA+ID4gKwkJCQkgICBzdHJ1Y3QgZGV2aWNlX2F0dHJpYnV0ZSAqYXR0ciwgY2hh ciAqYnVmKQo+ID4gPiArewo+ID4gPiArCXN0cnVjdCBkZXZfZXh0X2F0dHJpYnV0ZSAqZWF0dHI7 Cj4gPiA+ICsKPiA+ID4gKwllYXR0ciA9IGNvbnRhaW5lcl9vZihhdHRyLCBzdHJ1Y3QgZGV2X2V4 dF9hdHRyaWJ1dGUsIGF0dHIpOwo+ID4gPiArCj4gPiA+ICsJcmV0dXJuIHN5c2ZzX2VtaXQoYnVm LCAiY29uZmlnPTB4JWx4XG4iLCAodW5zaWduZWQgbG9uZyllYXR0ci0+dmFyKTsKPiA+ID4gK30K PiA+IAo+ID4gSSBhbSBub3QgdGhhdCBmYW1pbGlhciB3aXRoIHRoZSBwZXJmIGRyaXZlcnMsIHRo dXMgSSBtaWdodCBiZSBjb21wbGV0ZWx5Cj4gPiB3cm9uZyBoZXJlLCBidXQgdXN1YWxseSBmb3Ig c3lzZnMgb2JqZWN0cyBhIHNpbmdsZSB2YWx1ZSBpcyBwcmVmZXJyZWQsCj4gPiBzbyB0aGF0IHRo aXMgImNvbmZpZz0iIHRlY2huaWNhbGx5IHdvdWxkIG5vdCBiZSBuZWVkZWQsIHVubGVzcyB0aGlz IGlzCj4gPiBzb21ld2hhdCBlc3NlbnRpYWwgdG8gdGhlIGNvbnN1bWVycyBvZiB0aGlzIGF0dHJp YnV0ZSB0byBrbm93IHdoYXQgdGhlCj4gPiB2YWx1ZSBpcz8gwqBXaGF0IGRvIHlvdSB0aGluaz8K Pgo+ICJjb25maWc9IiBpcyBhIHN1cHBvcnRlZCBmb3IgdXNlcnNwYWNlIHRvb2wsIGl0IGlzIGEg a2luZCBvZiBhbGlhcywgc28KPiBjYW5ub3QgYmUgcmVtb3ZlciBoZXJlLCB0aGFua3MuCgpJIGRv bid0IHVuZGVyc3RhbmQgdGhpcyBwYXJ0LiAgVGhpcyBpcyBicmFuZC1uZXcgZnVuY3Rpb25hbGl0 eSBmb3IgdGhlCmtlcm5lbCwgc28gdGhlcmUncyBubyByZXF1aXJlbWVudCB0byBtYWludGFpbiBj b21wYXRpYmlsaXR5IGZvcgpleGlzdGluZyB1c2Vyc3BhY2UgdG9vbHMuCgpJZiB0aGVyZSdzIGEg c2ltaWxhciBzeXNmcyBzaG93IGZ1bmN0aW9uIGZvciBvdGhlciBwZXJmIGRyaXZlcnMsIGFuZAp5 b3UgbmVlZCB0byBiZSBjb21wYXRpYmxlIHdpdGggKnRoYXQqLCBmaW5lLiAgQnV0IGlmIHRoaXMg aXMgbWVyZWx5CmFib3V0IGJlaW5nIGNvbXBhdGlibGUgd2l0aCB1c2Vyc3BhY2UgdGhhdCB1c2Vz IG91dC1vZi10cmVlIGtlcm5lbApmdW5jdGlvbmFsaXR5LCB0aGF0J3Mgbm90IGEgcmVhbCBmYWN0 b3IuCgpCam9ybgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5p bmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8v bGludXgtYXJtLWtlcm5lbAo=