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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 6EBB2C433B4 for ; Thu, 1 Apr 2021 03:08:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 2440660240 for ; Thu, 1 Apr 2021 03:08:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2440660240 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44102 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lRngq-0000er-9M for qemu-devel@archiver.kernel.org; Wed, 31 Mar 2021 23:08:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33492) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRnd1-0005ic-Ua; Wed, 31 Mar 2021 23:04:15 -0400 Received: from ozlabs.org ([203.11.71.1]:41381) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRncq-00083R-8K; Wed, 31 Mar 2021 23:04:11 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 4F9p1C1Rnyz9sXG; Thu, 1 Apr 2021 14:03:59 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1617246239; bh=suh4e+0H1WTSrprX4LDtSEOedIqgTJvxZH+FUfsxQ1U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aHKjyR/AuFLJtqM0vfUJeP84QlKydz1y7w8mbHoASQVMh/zg/TZCewzStSDbePcRU 15YQGy3/UHbifdHZ3+AsJlEuilzatCnq3/tGqH5rOjSAT02dcKqKUXKoowQ2y3YvSJ 2+gdDQcsiWwZIqxOkdmsPwx2svCGEQAZhOUsrd/c= Date: Thu, 1 Apr 2021 13:53:48 +1100 From: David Gibson To: =?iso-8859-1?Q?C=E9dric?= Le Goater Subject: Re: [PATCH 1/2] spapr: number of SMP sockets must be equal to NUMA nodes Message-ID: References: <2025f26f-5883-4e86-02af-5b83a8d52465@gmail.com> <9870aaba-9921-5c5d-113c-5be6cd098cf2@kaod.org> <91e406bf-c9c6-0734-1f69-081d3633332b@gmail.com> <87blazyl5w.fsf@mpe.ellerman.id.au> <041ea566-62cd-0017-fbaa-bb56bd97d381@kaod.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="veLyJj+FzBZrdtvL" Content-Disposition: inline In-Reply-To: <041ea566-62cd-0017-fbaa-bb56bd97d381@kaod.org> Received-SPF: pass client-ip=203.11.71.1; envelope-from=dgibson@ozlabs.org; helo=ozlabs.org X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Thomas Huth , Srikar Dronamraju , Michael Ellerman , Daniel Henrique Barboza , qemu-devel@nongnu.org, groug@kaod.org, qemu-ppc@nongnu.org, Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --veLyJj+FzBZrdtvL Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Mar 31, 2021 at 05:22:39PM +0200, C=E9dric Le Goater wrote: > On 3/31/21 6:58 AM, Michael Ellerman wrote: > > David Gibson writes: > >> On Mon, Mar 29, 2021 at 03:32:37PM -0300, Daniel Henrique Barboza wrot= e: > > ... > >> > >>> We assign ibm,chip-id=3D0x0 to CPUs 0-3, but CPUs 2-3 are located in a > >>> different NUMA node than 0-1. This would mean that the same socket > >>> would belong to different NUMA nodes at the same time. > >> > >> Right... and I'm still not seeing why that's a problem. AFAICT that's > >> a possible, if unexpected, situation under real hardware - though > >> maybe not for POWER9 specifically. > >=20 > > I think I agree. > >=20 > >>> I believe this is what Cedric wants to be addressed. Given that the > >>> property is called after the OPAL property ibm,chip-id, the kernel > >>> expects that the property will have the same semantics as in OPAL. > >> > >> Even on powernv, I'm not clear why chip-id is tied into the NUMA > >> configuration, rather than getting all the NUMA info from > >> associativity properties. > >=20 > > AFAIK we don't use chip-id for anything related to NUMA, if we do I'd > > consider that a bug. >=20 > Since PAPR only has NUMA nodes, is the use of chip-id in XIVE PAPR=20 > considered as a bug ? I would say so. As noted in another thread, XIVE PAPR *doesn't* actually use chip_id. And even on PowerNV, I don't think this has any real connection to NUMA. For PowerNV we care about whether we're working within a single XIVE hardware instance, or across multiple. There's one XIVE per-chip, hence the relevance of chip-id. That happens to also match to NUMA topology on (currently existing) POWER9 chips, but I don't see that it inherently has to. > > We do use it for topology_physical_package_id(), but that's almost > > completely unused. >=20 > In that case, I think it should be fine to return -1 like under PowerVM. >=20 > Thanks, >=20 > C.=20 >=20 >=20 --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --veLyJj+FzBZrdtvL Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAmBlNbwACgkQbDjKyiDZ s5K+FhAAxgbQ7AR1a8LpRwYfDYOp+wdnR14OIaLl9xwzXJxZsxlHOuMJ2eqNVagT VpQnoYWIEFEXaNJuLw9dirQjX9TOjXNb4bg7a3E77n29c2xgweFTIZ0X572DMPpP H1njmA7p+Lfddq1iahtoGNsgpRnoFBLmqnm4ykKn4e6tLJj9rvx8TdtwvJCC84pT 3+5T/sHGpbfSmTU1U6mMmEo8VnPK7cPwWSltv27h4pcYUhKgFt/OMSgoN5qluozN cfiIlHBQ9k2JycUul/Osi2SS98MBD5uNNuZ6YWwtdQBQ8GJEGpi6oLkA7brD1dJO KiVcIUO2R5p52r2sl30+RlrKWhd2l8frejL6N/U7L5llINEjCIfcD/rheGkDosWN XJr055zo+Re8xa+UCPS/PNNdatHPTrcdb/D6LlXx8b8eicHUf1T51FO4Juo8Vugk fR6enoevhJw0E9hX98uPkZwCWckc7/4VDdt6k0l1oBWtJmSs3UtDin3Q+zzh6zzS o/bG40rdncyrP3K1DKlqfNgrByAF+iMDgaigfEDmY6vtlFnSQgtHeC8JbGg487Sy 57lIeOy0bcI8ay6/dnJkVTPeCU22IdGgd7MSbsU0DYph7/hwVuUzy4meBDADkeht n3UhXyeLHPCjgc6vd1Ob5HsBv7/dZ6qGB7woFeY/n2J2wLW7lzk= =adxM -----END PGP SIGNATURE----- --veLyJj+FzBZrdtvL--