From patchwork Thu Mar 28 17:03:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 13609226 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (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 9EF1939FCF for ; Thu, 28 Mar 2024 17:03:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711645407; cv=none; b=X4UhTapvpYW30GUegs28EG5H1jnzoYahu092IxXsH7a5Z0WcXtA4Wfk2s2Kmmgw9P4KKG0bE6LYxTEttl4N5F8Ux2bRRl2kqMgYshhrqLffCRURkoIexPRkE4sInHq/APj3AOKhXMNDfOn8o7J/yr8cBH54vVCaQnTP68u267h4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711645407; c=relaxed/simple; bh=VWLua73p7ZUAjdHrayoP/lX15Em4rPKgzz1/a9x1KxQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=SVRyS7VzszEWRzROMIYHzpEu0v4KRdMeP5k5iMyGO5jalHdPqhh5eQTLscAfSibDGU2aC7OZsrH3I8PQAVBVejLm6s0BQvYBdwMpZykEUXm7f1dEgMJlrpqKRxQp1fBm7Pr/vmfD+FLIV2jN/pZyyaaRW877tFrDkdXqDDs5E0U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=tHmPJZUC; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tHmPJZUC" Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dcbee93a3e1so1734847276.3 for ; Thu, 28 Mar 2024 10:03:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1711645404; x=1712250204; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=DyO3NL4DZ5+zyEmGrUmGhqOJCsHXA1HlVzHyeVmkchI=; b=tHmPJZUCToedZH0Khr2fAir1EVZdmg1TKq27+KLpk5ZLSTaQfmvRPaiRyMGES4y1rh YB9Tsnyz/W+i8cyNJTVrhL4VRJnoETtIUzTTx/Ge1wMKjIzii2YvGkH3a0DCRA2DBWPg i91BrwR2zxNpSYdik/d8MR2nzfGQOEWOaHMYgjuzpF/fPciQzsrBJCOdepOH2m0PCye6 NuH2Yw863EwNpW4nbuoEqSGRWESiZQVuqU74N02/DZJ/73WnQPww8InKq1yZfYGwXO/n nTXNcekTdlnSaX6fxILl3qQJjQcRcOoCLrMalGriKdciDPn+6fJbQrVIjnJfDHTQURUn XTPg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711645404; x=1712250204; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=DyO3NL4DZ5+zyEmGrUmGhqOJCsHXA1HlVzHyeVmkchI=; b=eBDqcVK3A7pNtkUSquIJkMQ6hSWHAuT6vTwwSopFyYkcFD8/ZBJWraK0BhgOqS4Zpd sCpOjv8tGfrGD3hnEsqCXOWHF1yTGVIOwjfaV9U4WUb7I099tYBqXtIeZmj2G9+hcD1C XhwdCeg8dmHFq9r5zF28B4PhbWRkJzFftmecnZjChvHfSTWL5W2qH+8JAyTndRzoFzkD AbMn8/d2piMfl43lX+SIGXv0095URlMxFaSkVox2AQuL0jJtGaur5Ch862WF0m9eOwhN +I0GrPUMRa+UOsHIhf0tG5aWa+ZwT2yFZ31KY6puyYyqWuVG+VB/K2j9zHt+dEoK/52v J8Kw== X-Gm-Message-State: AOJu0YzeQ56qysJsC9OWI3rlwkHYK74A5e4uItpSJYuwHySg1nXCTZHb FbmLN0OeF/zpp0lDkBZ0S/MzGGA6fwzkb2TRCS5n+MXCRIrNarxsmV9NRG2S4NuV1nq99MKv8vn hZVhLN9bjTA== X-Google-Smtp-Source: AGHT+IEcAU6On1FebhvDzRMHxKgc0gG9W0lAfWMgqvnygBHzEBD0mgjfLuzwj379NGUbm10JUxpCruxTKGqE3g== X-Received: from edumazet1.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:395a]) (user=edumazet job=sendgmr) by 2002:a05:6902:2292:b0:ddd:7581:1234 with SMTP id dn18-20020a056902229200b00ddd75811234mr207996ybb.11.1711645404695; Thu, 28 Mar 2024 10:03:24 -0700 (PDT) Date: Thu, 28 Mar 2024 17:03:08 +0000 In-Reply-To: <20240328170309.2172584-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240328170309.2172584-1-edumazet@google.com> X-Mailer: git-send-email 2.44.0.478.gd926399ef9-goog Message-ID: <20240328170309.2172584-8-edumazet@google.com> Subject: [PATCH net-next 7/8] net: rps: add rps_input_queue_head_add() helper From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet X-Patchwork-Delegate: kuba@kernel.org process_backlog() can batch increments of sd->input_queue_head, saving some memory bandwidth. Also add READ_ONCE()/WRITE_ONCE() annotations around sd->input_queue_head accesses. Signed-off-by: Eric Dumazet --- include/net/rps.h | 9 +++++++-- net/core/dev.c | 13 ++++++++----- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/include/net/rps.h b/include/net/rps.h index c13f829b8556fda63e76544c332f2c089f0d6ea4..135427bc6fcd29b9dad92a671c9a9f4efc975dec 100644 --- a/include/net/rps.h +++ b/include/net/rps.h @@ -51,13 +51,18 @@ static inline void rps_input_queue_tail_save(u32 *dest, u32 tail) #endif } -static inline void rps_input_queue_head_incr(struct softnet_data *sd) +static inline void rps_input_queue_head_add(struct softnet_data *sd, int val) { #ifdef CONFIG_RPS - sd->input_queue_head++; + WRITE_ONCE(sd->input_queue_head, sd->input_queue_head + val); #endif } +static inline void rps_input_queue_head_incr(struct softnet_data *sd) +{ + rps_input_queue_head_add(sd, 1); +} + /* * The rps_dev_flow_table structure contains a table of flow mappings. */ diff --git a/net/core/dev.c b/net/core/dev.c index 1fe7c6b10793d45a03461ee581d240d2442f9e17..59e7fc30e8f03880340bfbeda0fa9e9ac757a168 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4518,7 +4518,7 @@ set_rps_cpu(struct net_device *dev, struct sk_buff *skb, out: #endif rflow->last_qtail = - per_cpu(softnet_data, next_cpu).input_queue_head; + READ_ONCE(per_cpu(softnet_data, next_cpu).input_queue_head); } rflow->cpu = next_cpu; @@ -4600,7 +4600,7 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, */ if (unlikely(tcpu != next_cpu) && (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || - ((int)(per_cpu(softnet_data, tcpu).input_queue_head - + ((int)(READ_ONCE(per_cpu(softnet_data, tcpu).input_queue_head) - READ_ONCE(rflow->last_qtail))) >= 0)) { tcpu = next_cpu; rflow = set_rps_cpu(dev, skb, rflow, next_cpu); @@ -4655,7 +4655,7 @@ bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, rflow = &flow_table->flows[flow_id]; cpu = READ_ONCE(rflow->cpu); if (rflow->filter == filter_id && cpu < nr_cpu_ids && - ((int)(per_cpu(softnet_data, cpu).input_queue_head - + ((int)(READ_ONCE(per_cpu(softnet_data, cpu).input_queue_head) - READ_ONCE(rflow->last_qtail)) < (int)(10 * flow_table->mask))) expire = false; @@ -6035,9 +6035,10 @@ static int process_backlog(struct napi_struct *napi, int quota) rcu_read_lock(); __netif_receive_skb(skb); rcu_read_unlock(); - rps_input_queue_head_incr(sd); - if (++work >= quota) + if (++work >= quota) { + rps_input_queue_head_add(sd, work); return work; + } } @@ -6060,6 +6061,8 @@ static int process_backlog(struct napi_struct *napi, int quota) backlog_unlock_irq_enable(sd); } + if (work) + rps_input_queue_head_add(sd, work); return work; }