From patchwork Wed Oct 9 00:54:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joe Damato X-Patchwork-Id: 13827307 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-pl1-f182.google.com (mail-pl1-f182.google.com [209.85.214.182]) (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 6BD2529CEC for ; Wed, 9 Oct 2024 00:56:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728435367; cv=none; b=kEWKAMQtHBPknCfTRNAhwOLF1zWPW6idWb0cES/gb+HlRRKdBq1xWxDGHm9xHrdp7aYAbgDh1dppFpllHe6/Ecf0r13PTKmtYBDmLVhkah55fUjRS7fXRss6uvQHaBsjaw6lHqfRxss84HHJBE4nK45wZEsoloAcqeDxfzNSxFs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728435367; c=relaxed/simple; bh=OgnU7jGlYOZ4RgUbpwTEE1doBCYt+nNNnswKcF5DWLk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=d7959JSj5c2ht5+Z6juSx4KzLX1hcE2u8RiPirTI8DTfXrNeShFxh8PLXsotckEhLQFr9YUsX8SrDahsTnnQHMhsYAxYa5j8V0piXBCEzOZRyhU5YymPVprk7p51I/R2A6ONGWzJKTDlUrdeM5nyDS1qwKS6LmD9a1r4Te3zHK8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fastly.com; spf=pass smtp.mailfrom=fastly.com; dkim=pass (1024-bit key) header.d=fastly.com header.i=@fastly.com header.b=rHS5XO8d; arc=none smtp.client-ip=209.85.214.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fastly.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fastly.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=fastly.com header.i=@fastly.com header.b="rHS5XO8d" Received: by mail-pl1-f182.google.com with SMTP id d9443c01a7336-20c544d345cso2798725ad.1 for ; Tue, 08 Oct 2024 17:56:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastly.com; s=google; t=1728435364; x=1729040164; 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=n16XhemzbXx7qwcaB9LPA7EkmnNUbtxincb4Rdb9OsI=; b=rHS5XO8dkUU3o7d/3kMT1rFjpuzKmRr8/+yrpDMpZBSWuKBr/2nGo90dBlT1T8MrWh jtG01oIW3CBI85VRbrDE5XfIyHpRllm+fic9XEknqMGdawqAwExoJJlAwhpzqHSW0Eqe L2FIQoJosTfs/c8rbzA8UpuPufEiRo6BcNvmk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728435364; x=1729040164; 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=n16XhemzbXx7qwcaB9LPA7EkmnNUbtxincb4Rdb9OsI=; b=DFw7jPT37zDgcB2QTQrTH8bwHnH7KN6Wi8QpCfOHUpSailvBoP0inOmqYS+N07pIiV 1G7G8t8OwLH36NbJkNDosmxBorpLeQ1cYfB806NT4ILy90I3K4rTxZQ3uYkvrCiEOb48 6wBQ+6ThzuYSzn3CJX788wsuVQ9kytstapWczoJWHxXJHB9XWTn83+aTiEXmJfhINnQY XDFDEG/dIp6qA8oBr97zXg7XL2M4UCPxymInY5oBC+XlLLTo6iQEyGX3hSh/XV4KRcUZ s+yQWDOa6VRKVGK9RfdTuj2T5dw/M2BI9oXTgcyBtxFwXM1l9HeuqvSSjdIz7UWHvMs0 Ws1A== X-Gm-Message-State: AOJu0Yz4JrGVjiYuhlLOtRhpFL6C1ovhgfk39lMbdkBduWC0C2Qyz7jb wqRAGd1QY448AF3Bw1U3d8zgEgjiWBUAAwH/8bXfCRS8gulcXzxRMecP8iYZbuRLfS5Bq3NaCal fJrVrL8Aa2KmcL8vOMKUdjibEf1p+gadwNYRo1Xir04gYXUzYyyN91w1fkwKjNEpVXl0be4fmMQ QPsUqUAxtqJTlQIVo+YdqW2Eso+BfKKzhVFCg= X-Google-Smtp-Source: AGHT+IHR1SIa8oY4V7UBXp5AdvZXp4JzGRwj4HelaMVkmT5XlbsItqb8H1RCUr8fzXvBNtNPuWtGqw== X-Received: by 2002:a17:903:124d:b0:205:5c06:39e6 with SMTP id d9443c01a7336-20c4e19d98emr86680775ad.0.1728435364214; Tue, 08 Oct 2024 17:56:04 -0700 (PDT) Received: from localhost.localdomain ([2620:11a:c019:0:65e:3115:2f58:c5fd]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20c138cec92sm60996045ad.101.2024.10.08.17.56.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Oct 2024 17:56:03 -0700 (PDT) From: Joe Damato To: netdev@vger.kernel.org Cc: mkarsten@uwaterloo.ca, skhawaja@google.com, sdf@fomichev.me, bjorn@rivosinc.com, amritha.nambiar@intel.com, sridhar.samudrala@intel.com, willemdebruijn.kernel@gmail.com, Joe Damato , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jonathan Corbet , Jiri Pirko , Sebastian Andrzej Siewior , Lorenzo Bianconi , Kory Maincent , Johannes Berg , linux-doc@vger.kernel.org (open list:DOCUMENTATION), linux-kernel@vger.kernel.org (open list) Subject: [net-next v5 5/9] net: napi: Add napi_config Date: Wed, 9 Oct 2024 00:54:59 +0000 Message-Id: <20241009005525.13651-6-jdamato@fastly.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20241009005525.13651-1-jdamato@fastly.com> References: <20241009005525.13651-1-jdamato@fastly.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org Add a persistent NAPI config area for NAPI configuration to the core. Drivers opt-in to setting the persistent config for a NAPI by passing an index when calling netif_napi_add_config. napi_config is allocated in alloc_netdev_mqs, freed in free_netdev (after the NAPIs are deleted). Drivers which call netif_napi_add_config will have persistent per-NAPI settings: NAPI IDs, gro_flush_timeout, and defer_hard_irq settings. Per-NAPI settings are saved in napi_disable and restored in napi_enable. Co-developed-by: Martin Karsten Signed-off-by: Martin Karsten Signed-off-by: Joe Damato --- .../networking/net_cachelines/net_device.rst | 1 + include/linux/netdevice.h | 36 ++++++++- net/core/dev.c | 79 +++++++++++++++++-- net/core/dev.h | 12 +++ 4 files changed, 118 insertions(+), 10 deletions(-) diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Documentation/networking/net_cachelines/net_device.rst index 3ab663b6cf16..9d86720cb722 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -183,5 +183,6 @@ struct_dpll_pin* dpll_pin struct hlist_head page_pools struct dim_irq_moder* irq_moder u64 max_pacing_offload_horizon +struct_napi_config* napi_config unsigned_long gro_flush_timeout u32 napi_defer_hard_irqs diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4239a4a9d295..b65a901ab4e7 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -342,6 +342,15 @@ struct gro_list { */ #define GRO_HASH_BUCKETS 8 +/* + * Structure for per-NAPI config + */ +struct napi_config { + u64 gro_flush_timeout; + u32 defer_hard_irqs; + unsigned int napi_id; +}; + /* * Structure for NAPI scheduling similar to tasklet but with weighting */ @@ -379,6 +388,8 @@ struct napi_struct { struct list_head dev_list; struct hlist_node napi_hash_node; int irq; + int index; + struct napi_config *config; }; enum { @@ -1860,9 +1871,6 @@ enum netdev_reg_state { * allocated at register_netdev() time * @real_num_rx_queues: Number of RX queues currently active in device * @xdp_prog: XDP sockets filter program pointer - * @gro_flush_timeout: timeout for GRO layer in NAPI - * @napi_defer_hard_irqs: If not zero, provides a counter that would - * allow to avoid NIC hard IRQ, on busy queues. * * @rx_handler: handler for received packets * @rx_handler_data: XXX: need comments on this one @@ -2012,6 +2020,11 @@ enum netdev_reg_state { * where the clock is recovered. * * @max_pacing_offload_horizon: max EDT offload horizon in nsec. + * @napi_config: An array of napi_config structures containing per-NAPI + * settings. + * @gro_flush_timeout: timeout for GRO layer in NAPI + * @napi_defer_hard_irqs: If not zero, provides a counter that would + * allow to avoid NIC hard IRQ, on busy queues. * * FIXME: cleanup struct net_device such that network protocol info * moves out. @@ -2405,6 +2418,7 @@ struct net_device { struct dim_irq_moder *irq_moder; u64 max_pacing_offload_horizon; + struct napi_config *napi_config; unsigned long gro_flush_timeout; u32 napi_defer_hard_irqs; @@ -2657,6 +2671,22 @@ netif_napi_add_tx_weight(struct net_device *dev, netif_napi_add_weight(dev, napi, poll, weight); } +/** + * netif_napi_add_config - initialize a NAPI context with persistent config + * @dev: network device + * @napi: NAPI context + * @poll: polling function + * @index: the NAPI index + */ +static inline void +netif_napi_add_config(struct net_device *dev, struct napi_struct *napi, + int (*poll)(struct napi_struct *, int), int index) +{ + napi->index = index; + napi->config = &dev->napi_config[index]; + netif_napi_add_weight(dev, napi, poll, NAPI_POLL_WEIGHT); +} + /** * netif_napi_add_tx() - initialize a NAPI context to be used for Tx only * @dev: network device diff --git a/net/core/dev.c b/net/core/dev.c index fca2295f4d95..bd87232f7b37 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6503,6 +6503,22 @@ EXPORT_SYMBOL(napi_busy_loop); #endif /* CONFIG_NET_RX_BUSY_POLL */ +static void __napi_hash_add_with_id(struct napi_struct *napi, + unsigned int napi_id) +{ + napi->napi_id = napi_id; + hlist_add_head_rcu(&napi->napi_hash_node, + &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); +} + +static void napi_hash_add_with_id(struct napi_struct *napi, + unsigned int napi_id) +{ + spin_lock(&napi_hash_lock); + __napi_hash_add_with_id(napi, napi_id); + spin_unlock(&napi_hash_lock); +} + static void napi_hash_add(struct napi_struct *napi) { if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) @@ -6515,10 +6531,8 @@ static void napi_hash_add(struct napi_struct *napi) if (unlikely(++napi_gen_id < MIN_NAPI_ID)) napi_gen_id = MIN_NAPI_ID; } while (napi_by_id(napi_gen_id)); - napi->napi_id = napi_gen_id; - hlist_add_head_rcu(&napi->napi_hash_node, - &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); + __napi_hash_add_with_id(napi, napi_gen_id); spin_unlock(&napi_hash_lock); } @@ -6641,6 +6655,28 @@ void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index, } EXPORT_SYMBOL(netif_queue_set_napi); +static void napi_restore_config(struct napi_struct *n) +{ + n->defer_hard_irqs = n->config->defer_hard_irqs; + n->gro_flush_timeout = n->config->gro_flush_timeout; + /* a NAPI ID might be stored in the config, if so use it. if not, use + * napi_hash_add to generate one for us. It will be saved to the config + * in napi_disable. + */ + if (n->config->napi_id) + napi_hash_add_with_id(n, n->config->napi_id); + else + napi_hash_add(n); +} + +static void napi_save_config(struct napi_struct *n) +{ + n->config->defer_hard_irqs = n->defer_hard_irqs; + n->config->gro_flush_timeout = n->gro_flush_timeout; + n->config->napi_id = n->napi_id; + napi_hash_del(n); +} + void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, int (*poll)(struct napi_struct *, int), int weight) { @@ -6651,8 +6687,6 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, INIT_HLIST_NODE(&napi->napi_hash_node); hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); napi->timer.function = napi_watchdog; - napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); - napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout)); init_gro_hash(napi); napi->skb = NULL; INIT_LIST_HEAD(&napi->rx_list); @@ -6670,7 +6704,13 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, set_bit(NAPI_STATE_SCHED, &napi->state); set_bit(NAPI_STATE_NPSVC, &napi->state); list_add_rcu(&napi->dev_list, &dev->napi_list); - napi_hash_add(napi); + + /* default settings from sysfs are applied to all NAPIs. any per-NAPI + * configuration will be loaded in napi_enable + */ + napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); + napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout)); + napi_get_frags_check(napi); /* Create kthread for this napi if dev->threaded is set. * Clear dev->threaded if kthread creation failed so that @@ -6702,6 +6742,11 @@ void napi_disable(struct napi_struct *n) hrtimer_cancel(&n->timer); + if (n->config) + napi_save_config(n); + else + napi_hash_del(n); + clear_bit(NAPI_STATE_DISABLE, &n->state); } EXPORT_SYMBOL(napi_disable); @@ -6717,6 +6762,11 @@ void napi_enable(struct napi_struct *n) { unsigned long new, val = READ_ONCE(n->state); + if (n->config) + napi_restore_config(n); + else + napi_hash_add(n); + do { BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); @@ -6746,7 +6796,11 @@ void __netif_napi_del(struct napi_struct *napi) if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) return; - napi_hash_del(napi); + if (napi->config) { + napi->index = -1; + napi->config = NULL; + } + list_del_rcu(&napi->dev_list); napi_free_frags(napi); @@ -11083,6 +11137,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, unsigned int txqs, unsigned int rxqs) { struct net_device *dev; + size_t napi_config_sz; + unsigned int maxqs; BUG_ON(strlen(name) >= sizeof(dev->name)); @@ -11096,6 +11152,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, return NULL; } + maxqs = max(txqs, rxqs); + dev = kvzalloc(struct_size(dev, priv, sizeof_priv), GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); if (!dev) @@ -11170,6 +11228,11 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, if (!dev->ethtool) goto free_all; + napi_config_sz = array_size(maxqs, sizeof(*dev->napi_config)); + dev->napi_config = kvzalloc(napi_config_sz, GFP_KERNEL_ACCOUNT); + if (!dev->napi_config) + goto free_all; + strscpy(dev->name, name); dev->name_assign_type = name_assign_type; dev->group = INIT_NETDEV_GROUP; @@ -11231,6 +11294,8 @@ void free_netdev(struct net_device *dev) list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) netif_napi_del(p); + kvfree(dev->napi_config); + ref_tracker_dir_exit(&dev->refcnt_tracker); #ifdef CONFIG_PCPU_DEV_REFCNT free_percpu(dev->pcpu_refcnt); diff --git a/net/core/dev.h b/net/core/dev.h index 26e598aa56c3..f22cb532de7a 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -167,11 +167,17 @@ static inline void napi_set_defer_hard_irqs(struct napi_struct *n, u32 defer) static inline void netdev_set_defer_hard_irqs(struct net_device *netdev, u32 defer) { + unsigned int count = max(netdev->num_rx_queues, + netdev->num_tx_queues); struct napi_struct *napi; + int i; WRITE_ONCE(netdev->napi_defer_hard_irqs, defer); list_for_each_entry(napi, &netdev->napi_list, dev_list) napi_set_defer_hard_irqs(napi, defer); + + for (i = 0; i < count; i++) + netdev->napi_config[i].defer_hard_irqs = defer; } /** @@ -207,11 +213,17 @@ static inline void napi_set_gro_flush_timeout(struct napi_struct *n, static inline void netdev_set_gro_flush_timeout(struct net_device *netdev, unsigned long timeout) { + unsigned int count = max(netdev->num_rx_queues, + netdev->num_tx_queues); struct napi_struct *napi; + int i; WRITE_ONCE(netdev->gro_flush_timeout, timeout); list_for_each_entry(napi, &netdev->napi_list, dev_list) napi_set_gro_flush_timeout(napi, timeout); + + for (i = 0; i < count; i++) + netdev->napi_config[i].gro_flush_timeout = timeout; } int rps_cpumask_housekeeping(struct cpumask *mask);