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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 54F21C43465 for ; Mon, 21 Sep 2020 13:59:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1860620B1F for ; Mon, 21 Sep 2020 13:59:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600696799; bh=a4DF4W7dtH8e/HdbJnpntS4I8yTDTPerCU7Lh31WhNQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=rkGBQu6obTbx8SB0jGlOdvg1jbddNIh0X75Enw1w9rSVS85ISRmOKAfTIM5wST8bA J/mNlzYhl0ICLA3v8+6b5T/0KLvrMZDuLEyvfucPBvBWlL/jwAAzdLA12Qx5yQbYM2 vklF3Pn8SJrh7ZX28STG8d8Ut28i6nCdzFnokoNs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727246AbgIUN76 (ORCPT ); Mon, 21 Sep 2020 09:59:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:34346 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726496AbgIUN75 (ORCPT ); Mon, 21 Sep 2020 09:59:57 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (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 52F1E20866; Mon, 21 Sep 2020 13:59:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600696796; bh=a4DF4W7dtH8e/HdbJnpntS4I8yTDTPerCU7Lh31WhNQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=wg9S+ccqsDems1XcMj6eWPCpdmJ2G7w+rjxlyHduxbE5H7pjT+kzuyEjIROlO22rH JDTh02rcsjIObg8hrRocIUlihWizF1Ghdv/loTWSlrG9BWmGad/xgg14LZ+oJjN6wZ MgIcADkUToN3Vu5HCUYF0wrTHg+++B8cNEo52KJw= Date: Mon, 21 Sep 2020 14:59:52 +0100 From: Will Deacon To: Alexandru Elisei Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, maz@kernel.org, catalin.marinas@arm.com, swboyd@chromium.org, sumit.garg@linaro.org Subject: Re: [PATCH v6 0/7] arm_pmu: Use NMI for perf interrupt Message-ID: <20200921135951.GN2139@willie-the-truck> References: <20200819133419.526889-1-alexandru.elisei@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200819133419.526889-1-alexandru.elisei@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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? Will