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=-4.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 0F3A4C4360F for ; Wed, 20 Feb 2019 22:51:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D40922075B for ; Wed, 20 Feb 2019 22:51:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550703065; bh=0x9MVFXo+Y751qCaJ8GHk3d+/NV5RgOTWGaGMS1ouFA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=kOP7wk2VEDE5ELnWdCe2UpbkzHVS68ba0rbzlTvggJbRADzZVRkbXjG0SjeVKkTyc ZQDwzPaOoAhz4ahQBMVusC3O70lt9auX5V/FtNSsey8ESanB0x2ajbvKqodvQeoXuG x7RxvWifdLxTPB5tykBxY+9TQUTjoLf7iz5E//PU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726317AbfBTWvE (ORCPT ); Wed, 20 Feb 2019 17:51:04 -0500 Received: from mail-ot1-f65.google.com ([209.85.210.65]:38654 "EHLO mail-ot1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725847AbfBTWvD (ORCPT ); Wed, 20 Feb 2019 17:51:03 -0500 Received: by mail-ot1-f65.google.com with SMTP id m1so43141405otf.5; Wed, 20 Feb 2019 14:51:03 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=MXnskfauBnUogXYJgY5dNHOIdo9j55TU67g9oo5oqhM=; b=iY2UUx4XT1XIes809ngeklzqfZgg7VS8kJONQndZkEalSX1I36hQd9WW5K2h2hG9eQ K64z58NYOcyR7jHnFZi9cZF7uvh8PpRlYAmrvjrXmB7O7gNkg8mwKx2bYeES+o7//za5 IPgLQ6WqCsqfixVFaJmkGOTD2hr0LZ2QhVwAGCmv++UrNsyxvnV1INi6g6An5R5/pKt+ aCC4e6mKDJhEcD0o2gBTo15Jf/OUNbrz0tOE6xwt0V8PlBuX4N6tLVvGywNrKnKZh4qT 1QjcXnMcErMnkIW5A1enJHm7feKkNu71QsKrvj+mbsx/0bixoiA7tLuxccMmwgjHggJT MPfw== X-Gm-Message-State: AHQUAuZ/MdjdV2utkdyDRVjvBAd4jHTu8BoibtRr9dgehKWgBwuwQ6v7 0Pd5gqFRRfFCg+DtpsP8xT0EfhAbeO7T/FmJQ4E= X-Google-Smtp-Source: AHgI3IZRPgC4J+d8RrkM9iH9F5Zs+AMlNX5W8aBgKvrqXeUzhgCN/MVSc89/TZNlgaCEVUeLZkRcCiMgaC2iQSwbJBk= X-Received: by 2002:aca:ed0f:: with SMTP id l15mr7586917oih.76.1550703062784; Wed, 20 Feb 2019 14:51:02 -0800 (PST) MIME-Version: 1.0 References: <20190214171017.9362-1-keith.busch@intel.com> <20190214171017.9362-8-keith.busch@intel.com> <9ab5d6ba-4cb6-a6f1-894d-d79b77c8bc21@intel.com> <20190220224419.GC5478@localhost.localdomain> In-Reply-To: <20190220224419.GC5478@localhost.localdomain> From: "Rafael J. Wysocki" Date: Wed, 20 Feb 2019 23:50:52 +0100 Message-ID: Subject: Re: [PATCHv6 07/10] acpi/hmat: Register processor domain to its memory To: Keith Busch Cc: "Rafael J. Wysocki" , Dave Hansen , Linux Kernel Mailing List , ACPI Devel Maling List , Linux Memory Management List , Linux API , Greg Kroah-Hartman , Dan Williams Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 20, 2019 at 11:44 PM Keith Busch wrote: > > On Wed, Feb 20, 2019 at 11:21:45PM +0100, Rafael J. Wysocki wrote: > > On Wed, Feb 20, 2019 at 11:11 PM Dave Hansen wrote: > > > On 2/20/19 2:02 PM, Rafael J. Wysocki wrote: > > > >> diff --git a/drivers/acpi/hmat/Kconfig b/drivers/acpi/hmat/Kconfig > > > >> index c9637e2e7514..08e972ead159 100644 > > > >> --- a/drivers/acpi/hmat/Kconfig > > > >> +++ b/drivers/acpi/hmat/Kconfig > > > >> @@ -2,6 +2,7 @@ > > > >> config ACPI_HMAT > > > >> bool "ACPI Heterogeneous Memory Attribute Table Support" > > > >> depends on ACPI_NUMA > > > >> + select HMEM_REPORTING > > > > If you want to do this here, I'm not sure that defining HMEM_REPORTING > > > > as a user-selectable option is a good idea. In particular, I don't > > > > really think that setting ACPI_HMAT without it makes a lot of sense. > > > > Apart from this, the patch looks reasonable to me. > > > > > > I guess the question is whether we would want to allow folks to consume > > > the HMAT inside the kernel while not reporting it out via > > > HMEM_REPORTING. We have some in-kernel users of the HMAT lined up like > > > mitigations for memory-side caches. > > > > > > It's certainly possible that folks would want to consume those > > > mitigations without anything in sysfs. They might not even want or need > > > NUMA support itself, for instance. > > > > > > So, what should we do? > > > > > > config HMEM_REPORTING > > > bool # no user-visible prompt > > > default y if ACPI_HMAT > > > > > > So folks can override in their .config, but they don't see a prompt? > > > > Maybe it would be better to make HMEM_REPORTING do "select ACPI_HMAT if ACPI". > > > > The mitigations could then do that too if they depend on HMAT and > > ACPI_HMAT need not be user-visible at all. > > That sounds okay, though it would create unreachable code if !ACPI since > that's the only user for the new reporting interfaces. Until there are other users of it, you can make HMEM_REPORTING depend on ACPI_NUMA and select ACPI_HMAT.