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=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,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 6FCDECA9ECF for ; Mon, 4 Nov 2019 03:19:12 +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 3E01721D7D for ; Mon, 4 Nov 2019 03:19:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hZZit5UT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E01721D7D 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+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6jxUnmbQYkFTY4dCEX6/gmYcp/Oxzh9OeS22KcQupO0=; b=hZZit5UTYgW3u2 3M6xxt4FIjbg3j9NLOl8IUs/O3WUf1mpPSisK182TdtH0A83TJV1gAqUSVqeJ9U9OBaM+0WKQ70j5 SpfBpyqjzopdPE5dB2XX1LS9BrMLxL7THdRojMmtB7Hw9CvTzrILEuQKUl+IPjl5McNNdmvqaQhSI UwL9C9W4eyvXK4IEnu+Ximw2+iB5WUsyhsnBhXrG5VwC5YveCmm7VdcYBPP+CNcw37lfgxLS3+VQe opoEMJgAZIVDHKWjbCPyLRBKRsGZQXnd6zcwyEefMZPK2qgJMaW1FSImtRl7g6EIDLRrchM5Hv+QK RNswAq33kiiGp8cIUfPg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRStT-0002EF-Pn; Mon, 04 Nov 2019 03:19:03 +0000 Received: from szxga05-in.huawei.com ([45.249.212.191] helo=huawei.com) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iRStQ-0002Dr-2S for linux-arm-kernel@lists.infradead.org; Mon, 04 Nov 2019 03:19:02 +0000 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 0529E92CFD0DA0A73F3C; Mon, 4 Nov 2019 11:18:54 +0800 (CST) Received: from [127.0.0.1] (10.74.221.148) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.439.0; Mon, 4 Nov 2019 11:18:53 +0800 Subject: Re: [PATCH] arm64: perf: Simplify the ARMv8 PMUv3 event attributes To: Will Deacon , Robin Murphy References: <1572407177-48229-1-git-send-email-zhangshaokun@hisilicon.com> <20191031160804.GA28325@willie-the-truck> <20191101085319.GA3508@blommer> <20191101103616.GA2392@willie-the-truck> <20191101105557.GC2392@willie-the-truck> <00880214-70ea-d374-7a42-fa25e8c21cb6@hisilicon.com> From: Shaokun Zhang Message-ID: Date: Mon, 4 Nov 2019 11:18:53 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <00880214-70ea-d374-7a42-fa25e8c21cb6@hisilicon.com> X-Originating-IP: [10.74.221.148] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191103_191900_276294_A30BE4A9 X-CRM114-Status: GOOD ( 14.28 ) 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: Mark Rutland , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Will, On 2019/11/4 9:02, Shaokun Zhang wrote: > Hi Will, > > On 2019/11/1 18:55, Will Deacon wrote: >> On Fri, Nov 01, 2019 at 10:54:21AM +0000, Robin Murphy wrote: >>> On 2019-11-01 10:36 am, Will Deacon wrote: >>>> On Fri, Nov 01, 2019 at 08:53:19AM +0000, Mark Rutland wrote: >>>>> On Thu, Oct 31, 2019 at 04:08:04PM +0000, Will Deacon wrote: >>>>>> On Wed, Oct 30, 2019 at 11:46:17AM +0800, Shaokun Zhang wrote: >>>>>>> For each PMU event, there is a ARMV8_EVENT_ATTR(xx, XX) and >>>>>>> &armv8_event_attr_xx.attr.attr. Let's redefine the ARMV8_EVENT_ATTR >>>>>>> to simplify the armv8_pmuv3_event_attrs. >>>>>>> >>>>>>> Cc: Will Deacon >>>>>>> Cc: Mark Rutland >>>>>>> Signed-off-by: Shaokun Zhang >>>>>>> --- >>>>>>> arch/arm64/kernel/perf_event.c | 189 ++++++++++++++--------------------------- >>>>>>> 1 file changed, 65 insertions(+), 124 deletions(-) >>>>>>> >>>>>>> diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c >>>>>>> index a0b4f1bca491..d0f084939bcf 100644 >>>>>>> --- a/arch/arm64/kernel/perf_event.c >>>>>>> +++ b/arch/arm64/kernel/perf_event.c >>>>>>> @@ -159,132 +159,73 @@ armv8pmu_events_sysfs_show(struct device *dev, >>>>>>> } >>>>>> >>>>>> [...] >>>>>> >>>>>>> + (&((struct perf_pmu_events_attr[]) { \ >>>>>>> + { .attr = __ATTR(name, 0444, armv8pmu_events_sysfs_show, NULL), \ >>>>>>> + .id = config, } \ >>>>>>> + })[0].attr.attr) >>>>>> >>>>>> I don't get the need for the array here. Why can't you do: >>>>>> >>>>>> (&((struct perf_pmu_events_attr) { >>>>>> .attr = ..., >>>>>> .id = ..., >>>>>> }).attr.attr) >>>>> >>>>> You need want &(obj.attr.attr) rather than &(obj).attr.attr, i.e. >>>>> >>>>> #define ARMV8_EVENT_ATTR(name, config) \ >>>>> (&((struct perf_pmu_events_attr) { \ >>>>> .attr = __ATTR(name, 0444, armv8pmu_events_sysfs_show, NULL), \ >>>>> .id = config, \ >>>>> }.attr.attr)) >>>>> ... which compiles for me. >>>> >>>> Weird, the following compiles fine for me with both GCC and clang: >>>> >>>> #define ARMV8_EVENT_ATTR(name, config) \ >>>> (&((struct perf_pmu_events_attr) { \ >>>> .attr = __ATTR(name, 0444, armv8pmu_events_sysfs_show, NULL), \ >>>> .id = config, \ >>>> }).attr.attr) >>> >>> You know that the expressions are equivalent because unary "&" has lower >>> precedence than ".", right? ;) >> >> Right, which is why it's weird that Shaokun claims that the version I posted >> doesn't compile. I assume it didn't build for Mark either, hence his extra > > The GCC version is gcc (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.10) 5.4.0 20160609. > It's a little old ;-) Sorry for my noise, it's my mistake that I forgot to remove the brackets when deleted the array. #define ARMV8_EVENT_ATTR(name, config) \ - (&((struct perf_pmu_events_attr[]) { \ + (&((struct perf_pmu_events_attr) { \ { .attr = __ATTR(name, 0444, armv8pmu_events_sysfs_show, NULL), \ .id = config, } \ - })[0].attr.attr) + }).attr.attr) It works now if I follow your proposal completely.:-P Thanks, Shaokun > > Thanks, > Shaokun > >> brackets. >> >> Will >> >> . >> _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel