From patchwork Fri Oct 21 12:19:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Schneider X-Patchwork-Id: 13014707 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 078BFC433FE for ; Fri, 21 Oct 2022 12:19:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229959AbiJUMTt (ORCPT ); Fri, 21 Oct 2022 08:19:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229520AbiJUMTs (ORCPT ); Fri, 21 Oct 2022 08:19:48 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4345D31213 for ; Fri, 21 Oct 2022 05:19:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666354784; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3rE72XJ0aceUfKerGW2NwZqel/SiYDWpKRmJbhA8td4=; b=e70eOLm/U9zQvMRpWftedphDLBd6UXAqrhzAyEWdwrBdsf33y5wSEci4xefqJZLqwOX+4H WgoTkuNz7VC8J1kH6l2BHAlGocytE01D9nzrumMisnqO8/vE+nRjzW746ZjddnpDFu9MzJ UF/vZ33uDyk0+mJ1OQCkZIb+LoWuLxw= Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-588-s2tausviPpW0tF7qRxsyxw-1; Fri, 21 Oct 2022 08:19:43 -0400 X-MC-Unique: s2tausviPpW0tF7qRxsyxw-1 Received: by mail-qv1-f72.google.com with SMTP id x2-20020a0cff22000000b004bb07bf7557so1501423qvt.11 for ; Fri, 21 Oct 2022 05:19:43 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3rE72XJ0aceUfKerGW2NwZqel/SiYDWpKRmJbhA8td4=; b=i6E5Pj77oMyGCx/9rqxjT+jQR3fm5bkLG3b1/bMzSUZt6ZscIjPF4Cxv2llFFeuMGK e7UYFavVuvCq7oJJh3d0X2BSgdP0/7I0tgRfODk+6ZFuczG3WWESqnAGt3DyQuqFEdOv WA3iKJz5NJJRvnwHAf7Hnaj1vIwjD86ROW3f7XcfDkAWSob5p6/6vFu+y3cd5b+5myVV AAUcRO9kyKdd4G6KrFfkIhMPyqYCsU3LgDdj8xwEHFApJXVgacNYLmiX5rFLHVB1tl7z b5JnSRT9BovVd9EidECImFZqhL+ostnpn1VXPQuN/UI1DYyJTSdOWM9ih2e3G5I1aSVl jV4w== X-Gm-Message-State: ACrzQf0yVxqWh5r6yMZYck0ubMxfKLgOAMRiMCZnb0PhcUAm0C0nSsAf aSq46aFPSqNfKVxvSDZeMjf+3nEDJ7fz5lZg2+D2iOcDHHZ+Psct6HNFKppaqEtExeyhnVGd+TD 1H2jonY8srUWeXZM5hIhHGA== X-Received: by 2002:ac8:598b:0:b0:39d:9b6:69b3 with SMTP id e11-20020ac8598b000000b0039d09b669b3mr7962685qte.39.1666354782869; Fri, 21 Oct 2022 05:19:42 -0700 (PDT) X-Google-Smtp-Source: AMsMyM43z2VqBV6jSju6xBnB50pYpQbv/czfSsoiWVC0V+APInK010NQWXoC/xTaJ4deUqTqiOuPiQ== X-Received: by 2002:ac8:598b:0:b0:39d:9b6:69b3 with SMTP id e11-20020ac8598b000000b0039d09b669b3mr7962653qte.39.1666354782635; Fri, 21 Oct 2022 05:19:42 -0700 (PDT) Received: from vschneid.remote.csb ([149.71.65.94]) by smtp.gmail.com with ESMTPSA id i9-20020ac85c09000000b0039a610a04b1sm8043410qti.37.2022.10.21.05.19.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Oct 2022 05:19:41 -0700 (PDT) From: Valentin Schneider To: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Saeed Mahameed , Leon Romanovsky , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Yury Norov , Andy Shevchenko , Rasmus Villemoes , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Mel Gorman , Greg Kroah-Hartman , Heiko Carstens , Tony Luck , Jonathan Cameron , Gal Pressman , Tariq Toukan , Jesse Brandeburg Subject: [PATCH v5 1/3] sched/topology: Introduce sched_numa_hop_mask() Date: Fri, 21 Oct 2022 13:19:25 +0100 Message-Id: <20221021121927.2893692-2-vschneid@redhat.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221021121927.2893692-1-vschneid@redhat.com> References: <20221021121927.2893692-1-vschneid@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org Tariq has pointed out that drivers allocating IRQ vectors would benefit from having smarter NUMA-awareness - cpumask_local_spread() only knows about the local node and everything outside is in the same bucket. sched_domains_numa_masks is pretty much what we want to hand out (a cpumask of CPUs reachable within a given distance budget), introduce sched_numa_hop_mask() to export those cpumasks. Link: http://lore.kernel.org/r/20220728191203.4055-1-tariqt@nvidia.com Signed-off-by: Valentin Schneider --- include/linux/topology.h | 12 ++++++++++++ kernel/sched/topology.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+) diff --git a/include/linux/topology.h b/include/linux/topology.h index 4564faafd0e12..3e91ae6d0ad58 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -245,5 +245,17 @@ static inline const struct cpumask *cpu_cpu_mask(int cpu) return cpumask_of_node(cpu_to_node(cpu)); } +#ifdef CONFIG_NUMA +extern const struct cpumask *sched_numa_hop_mask(int node, int hops); +#else +static inline const struct cpumask *sched_numa_hop_mask(int node, int hops) +{ + if (node == NUMA_NO_NODE && !hops) + return cpu_online_mask; + + return ERR_PTR(-EOPNOTSUPP); +} +#endif /* CONFIG_NUMA */ + #endif /* _LINUX_TOPOLOGY_H */ diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 8739c2a5a54ea..e3cb8cc375204 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -2067,6 +2067,37 @@ int sched_numa_find_closest(const struct cpumask *cpus, int cpu) return found; } +/** + * sched_numa_hop_mask() - Get the cpumask of CPUs at most @hops hops away from + * @node + * @node: The node to count hops from. + * @hops: Include CPUs up to that many hops away. 0 means local node. + * + * Return: On success, a pointer to a cpumask of CPUs at most @hops away from + * @node, an error value otherwise. + * + * Requires rcu_lock to be held. Returned cpumask is only valid within that + * read-side section, copy it if required beyond that. + * + * Note that not all hops are equal in distance; see sched_init_numa() for how + * distances and masks are handled. + * Also note that this is a reflection of sched_domains_numa_masks, which may change + * during the lifetime of the system (offline nodes are taken out of the masks). + */ +const struct cpumask *sched_numa_hop_mask(unsigned int node, unsigned int hops) +{ + struct cpumask ***masks = rcu_dereference(sched_domains_numa_masks); + + if (node >= nr_node_ids || hops >= sched_domains_numa_levels) + return ERR_PTR(-EINVAL); + + if (!masks) + return ERR_PTR(-EBUSY); + + return masks[hops][node]; +} +EXPORT_SYMBOL_GPL(sched_numa_hop_mask); + #endif /* CONFIG_NUMA */ static int __sdt_alloc(const struct cpumask *cpu_map)