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,DKIM_VALID_AU,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 6CD6CC388F9 for ; Thu, 22 Oct 2020 15:37:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A4EB2463F for ; Thu, 22 Oct 2020 15:37:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603381075; bh=uPaF1r+32uicP8P83cuSfWMAglDZBepM1O6/jnk56II=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=q0lnOuInFBwqFUcHIRDo1dSfsUaShVOYcZh7wUJfGvntGuFC2PvLeFrxo6xMIqmpo vMvvVkKNFPLnSRGBjT1+i2e6UnU3YDzgDyx3024v5LzBjK/tMihBToksizQo9Sc5bo QxZAHcj9VjNl6wcKCjOlu9g3En38YoJiUozN1Zqo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S368662AbgJVPhy (ORCPT ); Thu, 22 Oct 2020 11:37:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:43084 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S368660AbgJVPhx (ORCPT ); Thu, 22 Oct 2020 11:37:53 -0400 Received: from localhost (173-25-83-245.client.mchsi.com [173.25.83.245]) (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 CF3872463D; Thu, 22 Oct 2020 15:37:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603381073; bh=uPaF1r+32uicP8P83cuSfWMAglDZBepM1O6/jnk56II=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=IUKPemNVFH0djshP1sj+uUZ8WeelqvjmREgqtTdLj/3hprIRZLuEW0izNxeatQR9E o1qd7+d4MfJIL64dAUwOHxrQOTVlIJvTb10fT9frLrY10i1V3zpxEMJcLeNSsD9+MD 6EHalyjEWT1jb7id8H/8mtGFFTAPHo/OBx7o5ezo= Date: Thu, 22 Oct 2020 10:37:50 -0500 From: Bjorn Helgaas To: Ian Kumlien Cc: Kai-Heng Feng , linux-pci , Alexander Duyck , "Saheed O. Bolarinwa" , Puranjay Mohan Subject: Re: [PATCH] Use maximum latency when determining L1 ASPM Message-ID: <20201022153750.GA503849@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Sun, Oct 18, 2020 at 01:35:27PM +0200, Ian Kumlien wrote: > On Sat, Oct 17, 2020 at 12:41 AM Ian Kumlien wrote: > > On Fri, Oct 16, 2020 at 11:28 PM Bjorn Helgaas wrote: > > > Can you please, please, collect these on your system, Ian? I assume > > > that you can easily collect it once without your patch, when you see > > > poor I211 NIC performance but the system is otherwise working. And > > > you can collect it again *with* your patch. Same Kconfig, same > > > *everything* except adding your patch. > > > > Yeah I can do that, but I would like the changes output from the > > latest patch suggestion > > running on Kai-Heng's system so we can actually see what it does... > > Is: > https://bugzilla.kernel.org/show_bug.cgi?id=209725 That's a great start. Can you attach the patch to the bugzilla too, please, so it is self-contained? And also the analysis of the path from Root Port to Endpoint, with the exit latencies of each link, the acceptable latency of the endpoint and (1) the computation done by the existing code that results in "latency < acceptable" that means we can enable ASPM, and (2) the correct computation per spec that results in "latency > acceptable" so we cannot enable ASPM? This analysis will be the core of the commit log, and the bugzilla with lspci info is the supporting evidence. Bjorn