From patchwork Mon Jun 3 09:28:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13683466 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 530BDC25B75 for ; Mon, 3 Jun 2024 09:34:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=K6MuJnN6l+n/4Pig1ykjhR7X87mcIZChxUXIgw1RvTE=; b=Piz4sz7X84rYKX LhxEJx27zkCBqNg29brmuhY/SnqTwu24wYUYERKRqy3o1hWQl6HXdoyfhelmEFHABC5K9CZu0y/HV 8FTMOkhtslkXwCROlVtWXJ/rrfQ61eTead/fTDTaFDVKRv/1YXH0WGcq7bAj7DzGZclQFIkHGeljV XqQ2CxFnLxKJDkYaHB/RlLkPHhLlDM4IoDyXEWFfb4frTu7hcEitIa6KbcQ8vty14GsDvSNECjSMA izFV7e52vL0Ach+KsJ78XI2nZOXOOCO3hMaNl/9/OYMgae/jqQNCfQ25FyOw9JQDAhyLa8kKIRE39 486QOcQsb7KRp+p0mh7A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sE44n-0000000GEwe-3cTH; Mon, 03 Jun 2024 09:34:02 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sE44a-0000000GEmM-49dr for linux-arm-kernel@lists.infradead.org; Mon, 03 Jun 2024 09:33:56 +0000 Received: from mail.maildlp.com (unknown [172.19.88.163]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4Vt7kB55pNz1yspx; Mon, 3 Jun 2024 17:30:26 +0800 (CST) Received: from kwepemd200014.china.huawei.com (unknown [7.221.188.8]) by mail.maildlp.com (Postfix) with ESMTPS id 6AA4F180063; Mon, 3 Jun 2024 17:33:41 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by kwepemd200014.china.huawei.com (7.221.188.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Mon, 3 Jun 2024 17:33:40 +0800 From: Yicong Yang To: , , , , , , CC: , , , , , , , , , , Subject: [PATCH 2/3] perf: arm_pmu: Only show online CPUs in device's "cpus" attribute Date: Mon, 3 Jun 2024 17:28:11 +0800 Message-ID: <20240603092812.46616-3-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20240603092812.46616-1-yangyicong@huawei.com> References: <20240603092812.46616-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemd200014.china.huawei.com (7.221.188.8) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240603_023349_536159_316ECC2B X-CRM114-Status: GOOD ( 13.91 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Yicong Yang When there're CPUs offline after system booting, perf will failed: [root@localhost ~]# /home/yang/perf stat -a -e armv8_pmuv3_0/cycles/ Error: The sys_perf_event_open() syscall returned with 19 (No such device) for event (cpu-clock). /bin/dmesg | grep -i perf may provide additional information. This is due to PMU's "cpus" is not updated and still contains offline CPUs and perf will try to open perf event on the offlined CPUs. Make "cpus" attribute only shows online CPUs and introduced a new "supported_cpus" where users can get the range of the CPUs this PMU supported monitoring. Signed-off-by: Yicong Yang --- drivers/perf/arm_pmu.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c index 8458fe2cebb4..acbb0e1d0414 100644 --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -558,13 +558,35 @@ static ssize_t cpus_show(struct device *dev, struct device_attribute *attr, char *buf) { struct arm_pmu *armpmu = to_arm_pmu(dev_get_drvdata(dev)); - return cpumap_print_to_pagebuf(true, buf, &armpmu->supported_cpus); + cpumask_var_t mask; + ssize_t n; + + /* If allocation failed then show the supported_cpus */ + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) + return cpumap_print_to_pagebuf(true, buf, &armpmu->supported_cpus); + + cpumask_and(mask, &armpmu->supported_cpus, cpu_online_mask); + n = cpumap_print_to_pagebuf(true, buf, mask); + free_cpumask_var(mask); + + return n; } static DEVICE_ATTR_RO(cpus); +static ssize_t supported_cpus_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct arm_pmu *armpmu = to_arm_pmu(dev_get_drvdata(dev)); + + return cpumap_print_to_pagebuf(true, buf, &armpmu->supported_cpus); +} + +static DEVICE_ATTR_RO(supported_cpus); + static struct attribute *armpmu_common_attrs[] = { &dev_attr_cpus.attr, + &dev_attr_supported_cpus.attr, NULL, };