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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 75A0DC47080 for ; Tue, 1 Jun 2021 10:25:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58A376139A for ; Tue, 1 Jun 2021 10:25:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233695AbhFAK07 (ORCPT ); Tue, 1 Jun 2021 06:26:59 -0400 Received: from foss.arm.com ([217.140.110.172]:46430 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233641AbhFAK0s (ORCPT ); Tue, 1 Jun 2021 06:26:48 -0400 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 5677711FB; Tue, 1 Jun 2021 03:25:07 -0700 (PDT) Received: from e113632-lin (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6A81A3F73D; Tue, 1 Jun 2021 03:25:06 -0700 (PDT) From: Valentin Schneider To: Marc Zyngier Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Thomas Gleixner , Lorenzo Pieralisi , Vincenzo Frascino Subject: Re: [RFC PATCH v2 00/10] irqchip/irq-gic: Optimize masking by leveraging EOImode=1 In-Reply-To: <87zgwgs9x0.wl-maz@kernel.org> References: <20210525173255.620606-1-valentin.schneider@arm.com> <87zgwgs9x0.wl-maz@kernel.org> Date: Tue, 01 Jun 2021 11:25:01 +0100 Message-ID: <87tumhg9vm.mognet@arm.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27/05/21 12:17, Marc Zyngier wrote: > On Tue, 25 May 2021 18:32:45 +0100, > Valentin Schneider wrote: >> I've tested this on my Ampere eMAG, which uncovered "fun" interactions with >> the MSI domains. Did the same trick as the Juno with the pl011. >> >> pNMIs cause said eMAG to freeze, but that's true even without my patches. I >> did try them out under QEMU+KVM and that looked fine, although that means I >> only got to test EOImode=0. I'll try to dig into this when I get some more >> cycles. > > That's interesting/worrying. As far as I remember, this machine uses > GIC500, which is a well known quantity. If pNMIs are causing issues, > that'd probably be a CPU interface problem. Can you elaborate on how > you tried to test that part? Just using the below benchmark? > Not even that, it would hang somewhere at boot. Julien suggested offline that it might be a problem with the secondaries' PMR initial value, but I really never got to do dig into it. >> >> Performance impact >> ================== >> >> Benchmark >> +++++++++ >> >> Finding a benchmark that leverages a force-threaded IRQ has proved to be >> somewhat of a pain, so I crafted my own. It's a bit daft, but so are most >> benchmarks (though this one might win a prize). > > I love it (and wrote similar hacks in my time)! :D Yay! > Can you put that up > somewhere so that I can run the same test on my own zoo and find out > how it fares? > The setup part is really fugly and I was too ashamed of it to link it in the cover letter; for ACPI I could simply use acpi_register_gsi() since that uses the right domain by default, but for DT I ended up adding a DT entry and a match table. I'll see about unifying this and I'll send it out your way. 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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 9136BC4708F for ; Tue, 1 Jun 2021 10:27:39 +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 56AC76139A for ; Tue, 1 Jun 2021 10:27:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56AC76139A Authentication-Results: mail.kernel.org; dmarc=fail (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=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:References :In-Reply-To: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=XRFm9CzV0Aae9MQ9cKolhdWvzx7tgPYaYNFyq56XmiU=; b=m9NpQ9Jbzmzjyf 049tnT8Z/9iq3F69mhMBeklIODI4vJQYXC+LeLxjQSoz18/KwErlsptawK1TsRoem+DtjThVSQoed 6Sf6ttw/DvlsPxPvyn7sg3VKXl23m1BQGNXK1meSnZQBA/VfuEDKb4+gcClHTgQBfYX7HiE/gTZXf PW4hhioADRP3Rla8SwnBMFbcbaeXlghquzfchKYD8Q1aHi6RXKjDZlkipwZGZ2Peqa045tSA90ITR zJsG30WlFR5kWcevJXvHcUpepjQ1bstCmelUuGGOFTilZdVsrrgA4WgjSGdkQ7tXDiaHXQ5Ux/IPt C5urM77mrbCwr5mH44Jg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lo1bC-00FuQK-VB; Tue, 01 Jun 2021 10:26:15 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lo1a9-00FtvL-Pk for linux-arm-kernel@lists.infradead.org; Tue, 01 Jun 2021 10:25:11 +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 5677711FB; Tue, 1 Jun 2021 03:25:07 -0700 (PDT) Received: from e113632-lin (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6A81A3F73D; Tue, 1 Jun 2021 03:25:06 -0700 (PDT) From: Valentin Schneider To: Marc Zyngier Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Thomas Gleixner , Lorenzo Pieralisi , Vincenzo Frascino Subject: Re: [RFC PATCH v2 00/10] irqchip/irq-gic: Optimize masking by leveraging EOImode=1 In-Reply-To: <87zgwgs9x0.wl-maz@kernel.org> References: <20210525173255.620606-1-valentin.schneider@arm.com> <87zgwgs9x0.wl-maz@kernel.org> Date: Tue, 01 Jun 2021 11:25:01 +0100 Message-ID: <87tumhg9vm.mognet@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210601_032509_930230_88106565 X-CRM114-Status: GOOD ( 16.13 ) 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="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 On 27/05/21 12:17, Marc Zyngier wrote: > On Tue, 25 May 2021 18:32:45 +0100, > Valentin Schneider wrote: >> I've tested this on my Ampere eMAG, which uncovered "fun" interactions with >> the MSI domains. Did the same trick as the Juno with the pl011. >> >> pNMIs cause said eMAG to freeze, but that's true even without my patches. I >> did try them out under QEMU+KVM and that looked fine, although that means I >> only got to test EOImode=0. I'll try to dig into this when I get some more >> cycles. > > That's interesting/worrying. As far as I remember, this machine uses > GIC500, which is a well known quantity. If pNMIs are causing issues, > that'd probably be a CPU interface problem. Can you elaborate on how > you tried to test that part? Just using the below benchmark? > Not even that, it would hang somewhere at boot. Julien suggested offline that it might be a problem with the secondaries' PMR initial value, but I really never got to do dig into it. >> >> Performance impact >> ================== >> >> Benchmark >> +++++++++ >> >> Finding a benchmark that leverages a force-threaded IRQ has proved to be >> somewhat of a pain, so I crafted my own. It's a bit daft, but so are most >> benchmarks (though this one might win a prize). > > I love it (and wrote similar hacks in my time)! :D Yay! > Can you put that up > somewhere so that I can run the same test on my own zoo and find out > how it fares? > The setup part is really fugly and I was too ashamed of it to link it in the cover letter; for ACPI I could simply use acpi_register_gsi() since that uses the right domain by default, but for DT I ended up adding a DT entry and a match table. I'll see about unifying this and I'll send it out your way. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel