From patchwork Sun Dec 17 21:32:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yury Norov X-Patchwork-Id: 13496010 Received: from mail-io1-f43.google.com (mail-io1-f43.google.com [209.85.166.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A2E4449F98; Sun, 17 Dec 2023 21:32:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Q2BgPGcK" Received: by mail-io1-f43.google.com with SMTP id ca18e2360f4ac-7b3b819f8a3so132375839f.1; Sun, 17 Dec 2023 13:32:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702848742; x=1703453542; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=S9EUtlC/PMv4Un3TQIvI6rNRv4BEn/NrIpICR/MmGos=; b=Q2BgPGcKFLcr1fSJmlUw66t671tYkTyrzSm9Vh2AwIyaqwNyPAgvO3nXj77HvgGG2n iH8Mij1vaDJQb10NbUr+UMUU/ksKH/owHnlIIUfI7hFBIxyVXA1dgamS8o3jN8UydJd4 pBonbJhd+ETQY/uV2N5P4A0YHBHdSSGm4veBsUIkjbQjVH69d08/nH1PcI/jVzbDaZ3m azP6OQwZDyry5J2YTw/ATC+O8lRORB8F3CLrSXqWfDQzDX7Z4BN+DfGFBU60vAoMLpaq RhKt3LAXWjV5iSe2wEi/NRUf3BY+GpjNlb6LDIBl5CFhfkNhriyccrneb8oYuzcTi83z BepA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702848742; x=1703453542; 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=S9EUtlC/PMv4Un3TQIvI6rNRv4BEn/NrIpICR/MmGos=; b=oGvwWY0bwvNQr2PM5guOv8+BtlzkOXZLvqyaAtGOiy6XavfWXO8FhEhRNDbb5HxIVQ D3YMZYlJhBOinqWwemWAuUXlPS0X9ooqvxafn+S56FXdJivALiNIDp6gW6xURvxX+UV1 WfJ2o+KKERvAibxV/XImUgMPHUczQmPc3ENzBMj1itWI2jF4mi/t+ABfj4MhIMQX8J8L WlFsG7qj53Ri1cwq4ODb2ZNqmBa4586yu5mfOcOtPDOuFqHggrmGmGcdGQA+T2nffJQa 0Ks2lx3iRKorED+AwkPceukLppGn0puYZyB2i21Q09Kluo5BJOxWvtiP5u0sF2zKjknv nMig== X-Gm-Message-State: AOJu0YzFd/rnCkdor1RysE+echqtElEdJ0ZkeedJAc5cHx/6AXIaWaMa lWXnY2/MqbyxZ8vgdj5PdNQ= X-Google-Smtp-Source: AGHT+IEtk5oBf0yL162N5sduVtfni1aVSJeCPUAgGE2Xbp4M7tnAcPmIbMNqo1Wg89oUvIg7rz6GvA== X-Received: by 2002:a92:ca4a:0:b0:35c:e547:d759 with SMTP id q10-20020a92ca4a000000b0035ce547d759mr15814238ilo.12.1702848741771; Sun, 17 Dec 2023 13:32:21 -0800 (PST) Received: from localhost ([2601:344:8301:57f0:9c41:1dd2:7d5d:e008]) by smtp.gmail.com with ESMTPSA id e4-20020a0df504000000b005d746ac7f6bsm8197364ywf.69.2023.12.17.13.32.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 Dec 2023 13:32:21 -0800 (PST) From: Yury Norov To: Souradeep Chakrabarti , kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, longli@microsoft.com, yury.norov@gmail.com, leon@kernel.org, cai.huoqing@linux.dev, ssengar@linux.microsoft.com, vkuznets@redhat.com, tglx@linutronix.de, linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org Cc: schakrabarti@microsoft.com, paulros@microsoft.com Subject: [PATCH 3/3] net: mana: add a function to spread IRQs per CPUs Date: Sun, 17 Dec 2023 13:32:14 -0800 Message-Id: <20231217213214.1905481-4-yury.norov@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231217213214.1905481-1-yury.norov@gmail.com> References: <20231217213214.1905481-1-yury.norov@gmail.com> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Souradeep investigated that the driver performs faster if IRQs are spread on CPUs with the following heuristics: 1. No more than one IRQ per CPU, if possible; 2. NUMA locality is the second priority; 3. Sibling dislocality is the last priority. Let's consider this topology: Node 0 1 Core 0 1 2 3 CPU 0 1 2 3 4 5 6 7 The most performant IRQ distribution based on the above topology and heuristics may look like this: IRQ Nodes Cores CPUs 0 1 0 0-1 1 1 1 2-3 2 1 0 0-1 3 1 1 2-3 4 2 2 4-5 5 2 3 6-7 6 2 2 4-5 7 2 3 6-7 The irq_setup() routine introduced in this patch leverages the for_each_numa_hop_mask() iterator and assigns IRQs to sibling groups as described above. According to [1], for NUMA-aware but sibling-ignorant IRQ distribution based on cpumask_local_spread() performance test results look like this: ./ntttcp -r -m 16 NTTTCP for Linux 1.4.0 --------------------------------------------------------- 08:05:20 INFO: 17 threads created 08:05:28 INFO: Network activity progressing... 08:06:28 INFO: Test run completed. 08:06:28 INFO: Test cycle finished. 08:06:28 INFO: ##### Totals: ##### 08:06:28 INFO: test duration :60.00 seconds 08:06:28 INFO: total bytes :630292053310 08:06:28 INFO: throughput :84.04Gbps 08:06:28 INFO: retrans segs :4 08:06:28 INFO: cpu cores :192 08:06:28 INFO: cpu speed :3799.725MHz 08:06:28 INFO: user :0.05% 08:06:28 INFO: system :1.60% 08:06:28 INFO: idle :96.41% 08:06:28 INFO: iowait :0.00% 08:06:28 INFO: softirq :1.94% 08:06:28 INFO: cycles/byte :2.50 08:06:28 INFO: cpu busy (all) :534.41% For NUMA- and sibling-aware IRQ distribution, the same test works 15% faster: ./ntttcp -r -m 16 NTTTCP for Linux 1.4.0 --------------------------------------------------------- 08:08:51 INFO: 17 threads created 08:08:56 INFO: Network activity progressing... 08:09:56 INFO: Test run completed. 08:09:56 INFO: Test cycle finished. 08:09:56 INFO: ##### Totals: ##### 08:09:56 INFO: test duration :60.00 seconds 08:09:56 INFO: total bytes :741966608384 08:09:56 INFO: throughput :98.93Gbps 08:09:56 INFO: retrans segs :6 08:09:56 INFO: cpu cores :192 08:09:56 INFO: cpu speed :3799.791MHz 08:09:56 INFO: user :0.06% 08:09:56 INFO: system :1.81% 08:09:56 INFO: idle :96.18% 08:09:56 INFO: iowait :0.00% 08:09:56 INFO: softirq :1.95% 08:09:56 INFO: cycles/byte :2.25 08:09:56 INFO: cpu busy (all) :569.22% [1] https://lore.kernel.org/all/20231211063726.GA4977@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net/ Signed-off-by: Yury Norov Co-developed-by: Souradeep Chakrabarti --- .../net/ethernet/microsoft/mana/gdma_main.c | 28 +++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index 6367de0c2c2e..11e64e42e3b2 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -1243,6 +1243,34 @@ void mana_gd_free_res_map(struct gdma_resource *r) r->size = 0; } +static __maybe_unused int irq_setup(unsigned int *irqs, unsigned int len, int node) +{ + const struct cpumask *next, *prev = cpu_none_mask; + cpumask_var_t cpus __free(free_cpumask_var); + int cpu, weight; + + if (!alloc_cpumask_var(&cpus, GFP_KERNEL)) + return -ENOMEM; + + rcu_read_lock(); + for_each_numa_hop_mask(next, node) { + weight = cpumask_weight_andnot(next, prev); + while (weight-- > 0) { + cpumask_andnot(cpus, next, prev); + for_each_cpu(cpu, cpus) { + if (len-- == 0) + goto done; + irq_set_affinity_and_hint(*irqs++, topology_sibling_cpumask(cpu)); + cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); + } + } + prev = next; + } +done: + rcu_read_unlock(); + return 0; +} + static int mana_gd_setup_irqs(struct pci_dev *pdev) { unsigned int max_queues_per_port = num_online_cpus();