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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 5CABCC433F5 for ; Wed, 22 Sep 2021 08:28:04 +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 146D661100 for ; Wed, 22 Sep 2021 08:28:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 146D661100 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:40244 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mSxbn-0005ik-78 for qemu-devel@archiver.kernel.org; Wed, 22 Sep 2021 04:28:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52198) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mSxaO-0004Fn-Lx for qemu-devel@nongnu.org; Wed, 22 Sep 2021 04:26:36 -0400 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:57876) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mSxaN-0004zV-4f for qemu-devel@nongnu.org; Wed, 22 Sep 2021 04:26:36 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-26-mbZCrEHyOnWxZ3PgIpfWqw-1; Wed, 22 Sep 2021 04:26:29 -0400 X-MC-Unique: mbZCrEHyOnWxZ3PgIpfWqw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5BC1A108468C; Wed, 22 Sep 2021 08:26:28 +0000 (UTC) Received: from bahia.huguette (unknown [10.39.192.167]) by smtp.corp.redhat.com (Postfix) with ESMTP id EB09F60854; Wed, 22 Sep 2021 08:26:26 +0000 (UTC) Date: Wed, 22 Sep 2021 10:26:25 +0200 From: Greg Kurz To: Daniel Henrique Barboza Subject: Re: [PATCH] spapr_numa.c: fixes in spapr_numa_FORM2_write_rtas_tables() Message-ID: <20210922102625.43c89e1f@bahia.huguette> In-Reply-To: <20210921194347.52347-1-danielhb413@gmail.com> References: <20210921194347.52347-1-danielhb413@gmail.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kaod.org Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Received-SPF: softfail client-ip=205.139.111.44; envelope-from=groug@kaod.org; helo=us-smtp-delivery-44.mimecast.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_SOFTFAIL=0.665 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: qemu-ppc@nongnu.org, qemu-devel@nongnu.org, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 21 Sep 2021 16:43:47 -0300 Daniel Henrique Barboza wrote: > This patch has a handful of modifications for the recent added > FORM2 support: >=20 > - there is no particular reason for both 'lookup_index_table' and > 'distance_table' to be allocated in the heap, since their sizes are > known right at the start of the function. Use static allocation in > them to spare a couple of g_new0() calls; >=20 > - to not allocate more than the necessary size in 'distance_table'. At > this moment the array is oversized due to allocating uint32_t for all > elements, when most of them fits in an uint8_t; >=20 > - create a NUMA_LOCAL_DISTANCE macro to avoid hardcoding the local > distance value. >=20 Not needed. A notion of minimal distance, which is obviously synonymous to local, already exists in the "sysemu/numa.h" header : #define NUMA_DISTANCE_MIN 10 > Signed-off-by: Daniel Henrique Barboza > --- > hw/ppc/spapr_numa.c | 35 +++++++++++++++++++---------------- > 1 file changed, 19 insertions(+), 16 deletions(-) >=20 > diff --git a/hw/ppc/spapr_numa.c b/hw/ppc/spapr_numa.c > index 58d5dc7084..039a0439c6 100644 > --- a/hw/ppc/spapr_numa.c > +++ b/hw/ppc/spapr_numa.c > @@ -19,6 +19,9 @@ > /* Moved from hw/ppc/spapr_pci_nvlink2.c */ > #define SPAPR_GPU_NUMA_ID (cpu_to_be32(1)) > =20 > +/* Macro to avoid hardcoding the local distance value */ > +#define NUMA_LOCAL_DISTANCE 10 > + > /* > * Retrieves max_dist_ref_points of the current NUMA affinity. > */ > @@ -500,17 +503,21 @@ static void spapr_numa_FORM2_write_rtas_tables(Spap= rMachineState *spapr, > MachineState *ms =3D MACHINE(spapr); > NodeInfo *numa_info =3D ms->numa_state->nodes; > int nb_numa_nodes =3D ms->numa_state->num_nodes; > + /* Lookup index table has an extra uint32_t with its length */ > + uint32_t lookup_index_table[nb_numa_nodes + 1]; > int distance_table_entries =3D nb_numa_nodes * nb_numa_nodes; > - g_autofree uint32_t *lookup_index_table =3D NULL; > - g_autofree uint32_t *distance_table =3D NULL; > - int src, dst, i, distance_table_size; > - uint8_t *node_distances; > + /* > + * Distance table is an uint8_t array with a leading uint32_t > + * containing its length. > + */ > + uint8_t distance_table[distance_table_entries + 4]; > + uint32_t *distance_table_length; > + int src, dst, i; > =20 > /* > * ibm,numa-lookup-index-table: array with length and a > * list of NUMA ids present in the guest. > */ > - lookup_index_table =3D g_new0(uint32_t, nb_numa_nodes + 1); > lookup_index_table[0] =3D cpu_to_be32(nb_numa_nodes); > =20 > for (i =3D 0; i < nb_numa_nodes; i++) { > @@ -518,8 +525,7 @@ static void spapr_numa_FORM2_write_rtas_tables(SpaprM= achineState *spapr, > } > =20 > _FDT(fdt_setprop(fdt, rtas, "ibm,numa-lookup-index-table", > - lookup_index_table, > - (nb_numa_nodes + 1) * sizeof(uint32_t))); > + lookup_index_table, sizeof(lookup_index_table))); > =20 > /* > * ibm,numa-distance-table: contains all node distances. First > @@ -531,11 +537,10 @@ static void spapr_numa_FORM2_write_rtas_tables(Spap= rMachineState *spapr, > * array because NUMA ids can be sparse (node 0 is the first, > * node 8 is the second ...). > */ > - distance_table =3D g_new0(uint32_t, distance_table_entries + 1); > - distance_table[0] =3D cpu_to_be32(distance_table_entries); > + distance_table_length =3D (uint32_t *)distance_table; > + distance_table_length[0] =3D cpu_to_be32(distance_table_entries); > =20 > - node_distances =3D (uint8_t *)&distance_table[1]; > - i =3D 0; > + i =3D 4; > =20 A comment reminding why we're doing that wouldn't hurt, e.g. /* Skip the array size (uint32_t) */ With these fixed, especially using NUMA_DISTANCE_MIN, you can add: Reviewed-by: Greg Kurz > for (src =3D 0; src < nb_numa_nodes; src++) { > for (dst =3D 0; dst < nb_numa_nodes; dst++) { > @@ -546,18 +551,16 @@ static void spapr_numa_FORM2_write_rtas_tables(Spap= rMachineState *spapr, > * adding the numa_info to retrieve distance info from. > */ > if (src =3D=3D dst) { > - node_distances[i++] =3D 10; > + distance_table[i++] =3D NUMA_LOCAL_DISTANCE; > continue; > } > =20 > - node_distances[i++] =3D numa_info[src].distance[dst]; > + distance_table[i++] =3D numa_info[src].distance[dst]; > } > } > =20 > - distance_table_size =3D distance_table_entries * sizeof(uint8_t) + > - sizeof(uint32_t); > _FDT(fdt_setprop(fdt, rtas, "ibm,numa-distance-table", > - distance_table, distance_table_size)); > + distance_table, sizeof(distance_table))); > } > =20 > /*