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=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 5511CC43469 for ; Mon, 21 Sep 2020 15:41:43 +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 CD59B20866 for ; Mon, 21 Sep 2020 15:41:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CYTLWadS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CD59B20866 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+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=merlin.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=ZURJpRUT0rTbWl2ahvubaX8Kz+rQw+pHc5rdvkbrY5w=; b=CYTLWadSWpJD4s/uO45OQHTWQ 80KuCNF04tyElzlaKQIulUBad3WWX0CCsEO+r0zfIU+x1JxI+41kIgcWWNNBjaw+ouUB4seWFEmej hlrjyPFku3CpvIAGmllY8N7U+Kl82ouxVPagocTIgKwPKMkRnQNyvhEtJaOUwWMyAUv1rwlJi88Uw 0Crgh37+zb6w/h+cBXJmjn1KHAyKnrrGm1siy6TnrVdwyvbm667z4pDVC1MZSHrIgGT7+RzDMtJ24 0FMdnRWgMaUP9UcC3OaSHYZlRktWZX1gp/jGgPiqK09/3BHEaZnh8YAN5bPZUc5QNRIwynSRP7FZU K2iSjNi3A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKNvG-0001D1-Sz; Mon, 21 Sep 2020 15:40:10 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKNvE-0001CN-3g for linux-arm-kernel@lists.infradead.org; Mon, 21 Sep 2020 15:40:08 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 38657147A; Mon, 21 Sep 2020 08:40:05 -0700 (PDT) Received: from [192.168.0.110] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 305293F718; Mon, 21 Sep 2020 08:40:04 -0700 (PDT) Subject: Re: [PATCH v6 0/7] arm_pmu: Use NMI for perf interrupt To: Will Deacon References: <20200819133419.526889-1-alexandru.elisei@arm.com> <20200921135951.GN2139@willie-the-truck> From: Alexandru Elisei Message-ID: <296304b8-aadd-817d-bb12-dc7524b6f0f5@arm.com> Date: Mon, 21 Sep 2020 16:41:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200921135951.GN2139@willie-the-truck> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200921_114008_218301_0EDB83BB X-CRM114-Status: GOOD ( 20.33 ) 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@arm.com, sumit.garg@linaro.org, maz@kernel.org, linux-kernel@vger.kernel.org, swboyd@chromium.org, catalin.marinas@arm.com, 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+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Will, Thank you so much for reviewing the series! On 9/21/20 2:59 PM, Will Deacon wrote: > On Wed, Aug 19, 2020 at 02:34:12PM +0100, Alexandru Elisei wrote: >> The series makes the arm_pmu driver use NMIs for the perf interrupt when >> NMIs are available on the platform (currently, only arm64 + GICv3). To make >> it easier to play with the patches, I've pushed a branch at [1]: > This mostly looks good to me, but see some of the comments I left on the > code. One other thing I'm not sure about is whether or not we should tell > userspace that we're using an NMI for the sampling. Do any other > architectures have a conditional NMI? I'm not sure about other architectures being able to configure the perf interrupt as NMI or a regular interrupt, I'll try to find out. Regardless of what the other architecture do, I am of the opinion that we should spell out explicitly when the PMU is using pseudo-NMIs, because it makes a huge difference in the accuracy of the instrumentation and the overall usefulness of perf. If I spin a v7 quickly, is it still time to merge the series for 5.10? Thanks, Alex _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel