From nobody Mon Feb 9 16:06:34 2026 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (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 0E67E176237 for ; Sun, 8 Sep 2024 16:08:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725811725; cv=none; b=fpJFfArqbdhsQUeXaXtp8g7lj2sYlEHCTFr50NSP86Irtx9zmLOWgxHaLpK/YZ2EYrsic6ej/VcQWZo8YTnb3ZtcOb4IusN24diG5nA29gavdcKnpcVX8J6t8Ef+ao1+J6tFw/miRPV6bHz4Tm2c/2X46M4hszJ/WP8abGeJIVA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725811725; c=relaxed/simple; bh=qZ0T8CKExRvD5T2B1Yh7TajT/3Et+GX0HYMbFOGpRZQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oy0UyJEsA3tJHSEjBcleHB1xOrzvolvGYCl8OzPRsCwgGnlqL1EkLL41H0EOFJsQrEz5G7utBrXFftRleFGGEXQc+mHeoFOG5xjLp1NHz2+JvUHjW/bwJRemos7kn5kce4lDogJmDz39iDc82oNSnwF5JpezLqSZx5sPNQK7iAk= 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=X35UlQLr; arc=none smtp.client-ip=209.85.214.171 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="X35UlQLr" Received: by mail-pl1-f171.google.com with SMTP id d9443c01a7336-206aee4073cso35927895ad.1 for ; Sun, 08 Sep 2024 09:08:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastly.com; s=google; t=1725811723; x=1726416523; 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=iiyI3KUrh2IbLXgMecroHUMIkcTz7Cey6giPzmfBc6M=; b=X35UlQLrm27ddHTcUnU2CVgp3rFZosh/uCoNiay7/1ArTVzzq9dU5qCTSMhgMnUhow 1hxVXG0GdsdSpwW4rjTpSvQbF2mP9xVdE95BLRQG/fIPyqJy2A2obBkSjqXejdUpiKwS d5yKr66ITZi6A0fmPcJFKYZ9O/SKHEEuXVkuI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725811723; x=1726416523; 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=iiyI3KUrh2IbLXgMecroHUMIkcTz7Cey6giPzmfBc6M=; b=W26xSiBIx302TFmTQZnMllawQ0Y3r76CvAtKMoINUCGheDAR+IA2PiLNTNxGbXmUNX hkp3p0xZLkaeYofzoWQ/IpMoirMMcfkL0dh1PXQwmXffCYK62DlYtZBSuQqEcn2a8PkA 0KFrY6rWmpqyn263/PhIqUVGjHZBK0T8VyZ6ZlzJpBjY9ZptNmv29sMo1ArkXOWex7Tl Ji8tfxHXm5p/Xo3Pkl3rLbntsz+NrYlD3wsiIpwHv8qDLziDnhB/cn75Mr/tG0AB4ihg Hk54pQ+fqbAKbvZ+FhTTSwaDJNLFBe9nNKNb0aPWT9KIQ+ulq8NAdF8vEWhYFvIxLgLI NDBA== X-Forwarded-Encrypted: i=1; AJvYcCXzsKza6h2lDLrWdqKFr+qLHFrWAmUt06LWdIUQUOT6gjdl8DVeUobjFi2BctaLXIdRGB1IdaVnHsSotEc=@vger.kernel.org X-Gm-Message-State: AOJu0YytigLJygvUixEsN7icf95qO57l1FYY7Tr+zGD00sXKCs9if6ew Z/9tqxkYqZvDHCLCZLDZcLCz/orIxIc3cKxQhxpaRqu/7pciFGgoYxmqaiOrP90= X-Google-Smtp-Source: AGHT+IGn8u85dwq4o1reUH1GhhZmDtmxxPG4rQjIJ7eMol+kaITAp2KDE1rStg8cebOoGXifDmTKXQ== X-Received: by 2002:a17:902:e888:b0:202:2fc8:da35 with SMTP id d9443c01a7336-206f06241femr125103985ad.55.1725811723333; Sun, 08 Sep 2024 09:08:43 -0700 (PDT) Received: from localhost.localdomain ([2620:11a:c019:0:65e:3115:2f58:c5fd]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20710f3179fsm21412535ad.258.2024.09.08.09.08.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Sep 2024 09:08:42 -0700 (PDT) From: Joe Damato To: netdev@vger.kernel.org Cc: mkarsten@uwaterloo.ca, kuba@kernel.org, skhawaja@google.com, sdf@fomichev.me, bjorn@rivosinc.com, amritha.nambiar@intel.com, sridhar.samudrala@intel.com, Joe Damato , "David S. Miller" , Eric Dumazet , Paolo Abeni , Jonathan Corbet , Jiri Pirko , Sebastian Andrzej Siewior , Lorenzo Bianconi , David Ahern , Johannes Berg , Breno Leitao , Alexander Lobakin , linux-doc@vger.kernel.org (open list:DOCUMENTATION), linux-kernel@vger.kernel.org (open list) Subject: [RFC net-next v2 3/9] net: napi: Make napi_defer_hard_irqs per-NAPI Date: Sun, 8 Sep 2024 16:06:37 +0000 Message-Id: <20240908160702.56618-4-jdamato@fastly.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240908160702.56618-1-jdamato@fastly.com> References: <20240908160702.56618-1-jdamato@fastly.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Allow per-NAPI defer_hard_irqs setting. The existing sysfs parameter is respected; writes to sysfs will write to all NAPI structs for the device and the net_device defer_hard_irq field. Reads from sysfs will read from the net_device field. sysfs code was updated to guard against what appears to be a potential overflow as the field is an int, but the value passed in is an unsigned long. The ability to set defer_hard_irqs on specific NAPI instances will be added in a later commit, via netdev-genl. Signed-off-by: Joe Damato --- .../networking/net_cachelines/net_device.rst | 1 - include/linux/netdevice.h | 2 +- net/core/dev.c | 10 ++--- net/core/dev.h | 40 +++++++++++++++++++ net/core/net-sysfs.c | 2 +- 5 files changed, 47 insertions(+), 8 deletions(-) diff --git a/Documentation/networking/net_cachelines/net_device.rst b/Docum= entation/networking/net_cachelines/net_device.rst index a82751c88d18..4cd801398c4e 100644 --- a/Documentation/networking/net_cachelines/net_device.rst +++ b/Documentation/networking/net_cachelines/net_device.rst @@ -99,7 +99,6 @@ unsigned_int num_rx_queues unsigned_int real_num_rx_queues - = read_mostly get_rps_cpu struct_bpf_prog* xdp_prog - = read_mostly netif_elide_gro() unsigned_long gro_flush_timeout - = read_mostly napi_complete_done -u32 napi_defer_hard_irqs - = read_mostly napi_complete_done unsigned_int gro_max_size - = read_mostly skb_gro_receive unsigned_int gro_ipv4_max_size - = read_mostly skb_gro_receive rx_handler_func_t* rx_handler read_mostly = - __netif_receive_skb_core diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 54da1c800e65..5a58cf61539e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2088,7 +2088,6 @@ struct net_device { unsigned int real_num_rx_queues; struct netdev_rx_queue *_rx; unsigned long gro_flush_timeout; - u32 napi_defer_hard_irqs; unsigned int gro_max_size; unsigned int gro_ipv4_max_size; rx_handler_func_t __rcu *rx_handler; @@ -2412,6 +2411,7 @@ struct net_device { =20 /** @irq_moder: dim parameters used if IS_ENABLED(CONFIG_DIMLIB). */ struct dim_irq_moder *irq_moder; + u32 napi_defer_hard_irqs; =20 u8 priv[] ____cacheline_aligned __counted_by(priv_len); diff --git a/net/core/dev.c b/net/core/dev.c index ca90e8cab121..9495448fedaa 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6228,7 +6228,7 @@ bool napi_complete_done(struct napi_struct *n, int wo= rk_done) if (work_done) { if (n->gro_bitmask) timeout =3D READ_ONCE(n->dev->gro_flush_timeout); - n->defer_hard_irqs_count =3D READ_ONCE(n->dev->napi_defer_hard_irqs); + n->defer_hard_irqs_count =3D napi_get_defer_hard_irqs(n); } if (n->defer_hard_irqs_count > 0) { n->defer_hard_irqs_count--; @@ -6366,7 +6366,7 @@ static void busy_poll_stop(struct napi_struct *napi, = void *have_poll_lock, bpf_net_ctx =3D bpf_net_ctx_set(&__bpf_net_ctx); =20 if (flags & NAPI_F_PREFER_BUSY_POLL) { - napi->defer_hard_irqs_count =3D READ_ONCE(napi->dev->napi_defer_hard_irq= s); + napi->defer_hard_irqs_count =3D napi_get_defer_hard_irqs(napi); timeout =3D READ_ONCE(napi->dev->gro_flush_timeout); if (napi->defer_hard_irqs_count && timeout) { hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINN= ED); @@ -6648,6 +6648,7 @@ void netif_napi_add_weight(struct net_device *dev, st= ruct napi_struct *napi, INIT_HLIST_NODE(&napi->napi_hash_node); hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); napi->timer.function =3D napi_watchdog; + napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); init_gro_hash(napi); napi->skb =3D NULL; INIT_LIST_HEAD(&napi->rx_list); @@ -11033,7 +11034,7 @@ void netdev_sw_irq_coalesce_default_on(struct net_d= evice *dev) =20 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { dev->gro_flush_timeout =3D 20000; - dev->napi_defer_hard_irqs =3D 1; + netdev_set_defer_hard_irqs(dev, 1); } } EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); @@ -11982,7 +11983,6 @@ static void __init net_dev_struct_check(void) CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real= _num_rx_queues); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_= flush_timeout); - CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, napi= _defer_hard_irqs); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_= max_size); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_= ipv4_max_size); CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_h= andler); @@ -11995,7 +11995,7 @@ static void __init net_dev_struct_check(void) CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_= ingress); #endif CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, napi= _storage); - CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 112); + CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 108); } =20 /* diff --git a/net/core/dev.h b/net/core/dev.h index 5654325c5b71..2584a7de189f 100644 --- a/net/core/dev.h +++ b/net/core/dev.h @@ -138,6 +138,46 @@ static inline void netif_set_gro_ipv4_max_size(struct = net_device *dev, WRITE_ONCE(dev->gro_ipv4_max_size, size); } =20 +/** + * napi_get_defer_hard_irqs - get the NAPI's defer_hard_irqs + * @n: napi struct to get the defer_hard_irqs field from + * + * Return: the per-NAPI value of the defar_hard_irqs field. + */ +static inline u32 napi_get_defer_hard_irqs(const struct napi_struct *n) +{ + if (n->napi_storage) + return READ_ONCE(n->napi_storage->defer_hard_irqs); + else + return READ_ONCE(n->dev->napi_defer_hard_irqs); +} + +/** + * napi_set_defer_hard_irqs - set the defer_hard_irqs for a napi + * @n: napi_struct to set the defer_hard_irqs field + * @defer: the value the field should be set to + */ +static inline void napi_set_defer_hard_irqs(struct napi_struct *n, u32 def= er) +{ + if (n->napi_storage) + WRITE_ONCE(n->napi_storage->defer_hard_irqs, defer); +} + +/** + * netdev_set_defer_hard_irqs - set defer_hard_irqs for all NAPIs of a net= dev + * @netdev: the net_device for which all NAPIs will have their defer_hard_= irqs set + * @defer: the defer_hard_irqs value to set + */ +static inline void netdev_set_defer_hard_irqs(struct net_device *netdev, + u32 defer) +{ + struct napi_struct *napi; + + 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); +} + int rps_cpumask_housekeeping(struct cpumask *mask); =20 #if defined(CONFIG_DEBUG_NET) && defined(CONFIG_BPF_SYSCALL) diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 0648dbf0e234..0a0bbbfb39b4 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -429,7 +429,7 @@ static int change_napi_defer_hard_irqs(struct net_devic= e *dev, unsigned long val if (val > S32_MAX) return -ERANGE; =20 - WRITE_ONCE(dev->napi_defer_hard_irqs, val); + netdev_set_defer_hard_irqs(dev, (u32)val); return 0; } =20 --=20 2.25.1