From patchwork Fri Sep 23 15:55:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Schneider X-Patchwork-Id: 12986723 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 25E54C6FA82 for ; Fri, 23 Sep 2022 15:56:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232743AbiIWP4b (ORCPT ); Fri, 23 Sep 2022 11:56:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232331AbiIWP4I (ORCPT ); Fri, 23 Sep 2022 11:56:08 -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 B8A51146FBE for ; Fri, 23 Sep 2022 08:56:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1663948567; 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=kHBrvEPvwtrxok/newbrf2agVKLCITkG2Qf6CtamOLw=; b=TbcIWgCCgTefQjXAvmu4kZ46SwacUqEk+mk1jLiOOtE9UfbglZ+8FT6aMDukm6MrZDFsxI FCBSWP+4N5MM3LS+8js53z45fU6NPC1ZAhX1Ycz0VfXC/Yo4+oCkIXYW1FISH6Bx3MC7oP gGHt28PaR5m5ph4Dgal9LUDetQoE/y0= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-232-qelISEC1MlO-kESRKZ-r9A-1; Fri, 23 Sep 2022 11:56:06 -0400 X-MC-Unique: qelISEC1MlO-kESRKZ-r9A-1 Received: by mail-wr1-f70.google.com with SMTP id a13-20020adfbc4d000000b00228631ddfafso117138wrh.9 for ; Fri, 23 Sep 2022 08:56:05 -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; bh=kHBrvEPvwtrxok/newbrf2agVKLCITkG2Qf6CtamOLw=; b=yPh2s6RkxVr76byF7o1daVIU5KvzNjpSKC5+LmAJz3ouFMYRUtM5Q5enLLykGNhHvd 0wSYu2u0anh2Nrh5dj7HOi3kiGXeK7gob73r50ypAgfyfWcy8OhpeTr/gmyneMInhuxd dCk+IliRr60id9c8OyySpbiZnusENFG/e4SBkMD7S7anrbycoKmY2pXE7051YE1oq0Z7 5+IvMMMVG4pnlpq05lQWXPNiv8d17u6KU/H4ociStwrbW+2RvmfpdLXmDmJQSYTAmkbh 2VGrTZcQkOBzRJ27clwbqUVSCeDH3PH0jbSN7h5BbQ1hL/KSimpvFW2rdaYRMziol6E7 bnkQ== X-Gm-Message-State: ACrzQf2MuLWFfoXCA14UchtiwdEvVpNXXB7IRjGkvSacE+WZdqy2Rmuw 964Lgm5MRnRZ0tq0tz1YoiUC6rMbhPUV0ojWoPhK3AufY0MyTwz1l5JRvF1t7mu2mZl2Set5pm2 aYXlUSHjXEL0cjC+jMCOFdw== X-Received: by 2002:a05:600c:1c22:b0:3b4:b2bc:15e4 with SMTP id j34-20020a05600c1c2200b003b4b2bc15e4mr6572332wms.69.1663948564543; Fri, 23 Sep 2022 08:56:04 -0700 (PDT) X-Google-Smtp-Source: AMsMyM4Cc+v1ZHKhGIhntGRkSRg5WAmD2mSxUj/B+KSYr9+DHgV96QzjwDqWCHxzt9g3noPgOYYFEA== X-Received: by 2002:a05:600c:1c22:b0:3b4:b2bc:15e4 with SMTP id j34-20020a05600c1c2200b003b4b2bc15e4mr6572323wms.69.1663948564353; Fri, 23 Sep 2022 08:56:04 -0700 (PDT) Received: from vschneid.remote.csb ([185.11.37.247]) by smtp.gmail.com with ESMTPSA id i7-20020a5d5587000000b0021badf3cb26sm9055429wrv.63.2022.09.23.08.56.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Sep 2022 08:56:03 -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 v4 5/7] sched/topology: Introduce sched_numa_hop_mask() Date: Fri, 23 Sep 2022 16:55:40 +0100 Message-Id: <20220923155542.1212814-4-vschneid@redhat.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220923132527.1001870-1-vschneid@redhat.com> References: <20220923132527.1001870-1-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 4564faafd0e1..3e91ae6d0ad5 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 8739c2a5a54e..ee77706603c0 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. + * @node: The node to count hops from. + * @hops: Include CPUs up to that many hops away. 0 means local node. + * + * 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(int node, int hops) +{ + struct cpumask ***masks = rcu_dereference(sched_domains_numa_masks); + + if (node == NUMA_NO_NODE && !hops) + return cpu_online_mask; + + if (node >= nr_node_ids || hops >= sched_domains_numa_levels) + return ERR_PTR(-EINVAL); + + if (!masks) + return NULL; + + return masks[hops][node]; +} +EXPORT_SYMBOL_GPL(sched_numa_hop_mask); + #endif /* CONFIG_NUMA */ static int __sdt_alloc(const struct cpumask *cpu_map)