From patchwork Tue Jun 18 07:13:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 13701874 X-Patchwork-Delegate: kuba@kernel.org Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 84E70158865; Tue, 18 Jun 2024 07:25:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718695543; cv=none; b=E5bYDBlVWJq+1EV+TJaHnOD7pocNY9z+hbDPJ9wUFcnHYB8b9Mt00w02xtPJVnd1ajHVXU4uyeYxerNPSs+oRkUqgC7eenniYJQ0xp9Tmriit1AkiZg5F47I8P7RbwGzUw1t5e21rOMBOf9jfNTFep18Y96x1PSe2MLRlBqlq+Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718695543; c=relaxed/simple; bh=AILTKubynh89FLu8HjS/1RmnpyzfWyTJv2ROfVWh1XA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=rfeGJa/TrfnMqbkliumCsputBVi9/MFcJVtWAKxvozUvt2qQhABKyqshEAxOyprvAUm4A4r8QjYX0O6nE1ZcFbAx3vd+lD0aeMkSCNV/sEpivzk9cRx3wduL73Z84AaMlFKzX/c00YXyBL7EIlwZhDcaevv4QQcgbyM+rtIy540= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=1jLcmpYK; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=jaqQzMUG; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="1jLcmpYK"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="jaqQzMUG" From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1718695538; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O/B/Ax1MdN2tzKA6h5jb7c6aOkazs4RkGi0tSv3V+vo=; b=1jLcmpYKxW08/BRyEhU68B9z7wKfycp/FWl42XHQ/3PqEoTy8c4kiauNOynGI1gPyym3QG MB4pvvzWpKKf3e3bz7s612Uvf5RCckVE+3jgLg1Doc2mGHSJuzq33xBs0vinVqs39CaADA p+0/eOHZiKw+BfmsJ/PcNexDXaNTANcBUPYXhC/yrNijHED/WxsukGyh7bz8r0wRWlc4Kd 4NCfFONpxsECJPsf7cEbAvQDm4M0uHxzRxugtVnUcEg7hFXNO71cWUtXTHUj4rk9JXH+49 eTlxq9qLZMyhu8I7uemCnLF2Q9jPx0csbA+w1plR3lUXrb6Q1JNY8Ag0ili8FA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1718695538; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O/B/Ax1MdN2tzKA6h5jb7c6aOkazs4RkGi0tSv3V+vo=; b=jaqQzMUGwLgMP/LDmcVU9Bcin5J6agtjN2zzoL6RFJCNOSQsBzXTER7Lbf0Tp5dgno3PrA NxSiw6/lVeYEeMCQ== To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: "David S. Miller" , Daniel Bristot de Oliveira , Boqun Feng , Daniel Borkmann , Eric Dumazet , Frederic Weisbecker , Ingo Molnar , Jakub Kicinski , Paolo Abeni , Peter Zijlstra , Thomas Gleixner , Waiman Long , Will Deacon , Sebastian Andrzej Siewior , =?utf-8?b?QmrDtnJuIFQ=?= =?utf-8?b?w7ZwZWw=?= , Alexei Starovoitov , Andrii Nakryiko , Eduard Zingerman , Hao Luo , Jesper Dangaard Brouer , Jiri Olsa , John Fastabend , Jonathan Lemon , KP Singh , Maciej Fijalkowski , Magnus Karlsson , Martin KaFai Lau , Song Liu , Stanislav Fomichev , =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rge?= =?utf-8?q?nsen?= , Yonghong Song , bpf@vger.kernel.org Subject: [PATCH v7 net-next 15/15] net: Move per-CPU flush-lists to bpf_net_context on PREEMPT_RT. Date: Tue, 18 Jun 2024 09:13:31 +0200 Message-ID: <20240618072526.379909-16-bigeasy@linutronix.de> In-Reply-To: <20240618072526.379909-1-bigeasy@linutronix.de> References: <20240618072526.379909-1-bigeasy@linutronix.de> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org The per-CPU flush lists, which are accessed from within the NAPI callback (xdp_do_flush() for instance), are per-CPU. There are subject to the same problem as struct bpf_redirect_info. Add the per-CPU lists cpu_map_flush_list, dev_map_flush_list and xskmap_map_flush_list to struct bpf_net_context. Add wrappers for the access. The lists initialized on first usage (similar to bpf_net_ctx_get_ri()). Cc: "Björn Töpel" Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Eduard Zingerman Cc: Hao Luo Cc: Jesper Dangaard Brouer Cc: Jiri Olsa Cc: John Fastabend Cc: Jonathan Lemon Cc: KP Singh Cc: Maciej Fijalkowski Cc: Magnus Karlsson Cc: Martin KaFai Lau Cc: Song Liu Cc: Stanislav Fomichev Cc: Toke Høiland-Jørgensen Cc: Yonghong Song Cc: bpf@vger.kernel.org Reviewed-by: Toke Høiland-Jørgensen Signed-off-by: Sebastian Andrzej Siewior Acked-by: Jesper Dangaard Brouer --- include/linux/filter.h | 42 ++++++++++++++++++++++++++++++++++++++++++ kernel/bpf/cpumap.c | 19 +++---------------- kernel/bpf/devmap.c | 11 +++-------- net/xdp/xsk.c | 12 ++++-------- 4 files changed, 52 insertions(+), 32 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 0a7f6e4a00b60..c0349522de8fb 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -736,6 +736,9 @@ struct bpf_nh_params { /* flags for bpf_redirect_info kern_flags */ #define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */ #define BPF_RI_F_RI_INIT BIT(1) +#define BPF_RI_F_CPU_MAP_INIT BIT(2) +#define BPF_RI_F_DEV_MAP_INIT BIT(3) +#define BPF_RI_F_XSK_MAP_INIT BIT(4) struct bpf_redirect_info { u64 tgt_index; @@ -750,6 +753,9 @@ struct bpf_redirect_info { struct bpf_net_context { struct bpf_redirect_info ri; + struct list_head cpu_map_flush_list; + struct list_head dev_map_flush_list; + struct list_head xskmap_map_flush_list; }; static inline struct bpf_net_context *bpf_net_ctx_set(struct bpf_net_context *bpf_net_ctx) @@ -787,6 +793,42 @@ static inline struct bpf_redirect_info *bpf_net_ctx_get_ri(void) return &bpf_net_ctx->ri; } +static inline struct list_head *bpf_net_ctx_get_cpu_map_flush_list(void) +{ + struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); + + if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_CPU_MAP_INIT)) { + INIT_LIST_HEAD(&bpf_net_ctx->cpu_map_flush_list); + bpf_net_ctx->ri.kern_flags |= BPF_RI_F_CPU_MAP_INIT; + } + + return &bpf_net_ctx->cpu_map_flush_list; +} + +static inline struct list_head *bpf_net_ctx_get_dev_flush_list(void) +{ + struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); + + if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_DEV_MAP_INIT)) { + INIT_LIST_HEAD(&bpf_net_ctx->dev_map_flush_list); + bpf_net_ctx->ri.kern_flags |= BPF_RI_F_DEV_MAP_INIT; + } + + return &bpf_net_ctx->dev_map_flush_list; +} + +static inline struct list_head *bpf_net_ctx_get_xskmap_flush_list(void) +{ + struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); + + if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_XSK_MAP_INIT)) { + INIT_LIST_HEAD(&bpf_net_ctx->xskmap_map_flush_list); + bpf_net_ctx->ri.kern_flags |= BPF_RI_F_XSK_MAP_INIT; + } + + return &bpf_net_ctx->xskmap_map_flush_list; +} + /* Compute the linear packet data range [data, data_end) which * will be accessed by various program types (cls_bpf, act_bpf, * lwt, ...). Subsystems allowing direct data access must (!) diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 66974bd027109..068e994ed781a 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -79,8 +79,6 @@ struct bpf_cpu_map { struct bpf_cpu_map_entry __rcu **cpu_map; }; -static DEFINE_PER_CPU(struct list_head, cpu_map_flush_list); - static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) { u32 value_size = attr->value_size; @@ -709,7 +707,7 @@ static void bq_flush_to_queue(struct xdp_bulk_queue *bq) */ static void bq_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_frame *xdpf) { - struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_cpu_map_flush_list(); struct xdp_bulk_queue *bq = this_cpu_ptr(rcpu->bulkq); if (unlikely(bq->count == CPU_MAP_BULK_SIZE)) @@ -761,7 +759,7 @@ int cpu_map_generic_redirect(struct bpf_cpu_map_entry *rcpu, void __cpu_map_flush(void) { - struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_cpu_map_flush_list(); struct xdp_bulk_queue *bq, *tmp; list_for_each_entry_safe(bq, tmp, flush_list, flush_node) { @@ -775,20 +773,9 @@ void __cpu_map_flush(void) #ifdef CONFIG_DEBUG_NET bool cpu_map_check_flush(void) { - if (list_empty(this_cpu_ptr(&cpu_map_flush_list))) + if (list_empty(bpf_net_ctx_get_cpu_map_flush_list())) return false; __cpu_map_flush(); return true; } #endif - -static int __init cpu_map_init(void) -{ - int cpu; - - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(&per_cpu(cpu_map_flush_list, cpu)); - return 0; -} - -subsys_initcall(cpu_map_init); diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index fbfdfb60db8d7..317ac2d66ebd1 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -83,7 +83,6 @@ struct bpf_dtab { u32 n_buckets; }; -static DEFINE_PER_CPU(struct list_head, dev_flush_list); static DEFINE_SPINLOCK(dev_map_lock); static LIST_HEAD(dev_map_list); @@ -415,7 +414,7 @@ static void bq_xmit_all(struct xdp_dev_bulk_queue *bq, u32 flags) */ void __dev_flush(void) { - struct list_head *flush_list = this_cpu_ptr(&dev_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_dev_flush_list(); struct xdp_dev_bulk_queue *bq, *tmp; list_for_each_entry_safe(bq, tmp, flush_list, flush_node) { @@ -429,7 +428,7 @@ void __dev_flush(void) #ifdef CONFIG_DEBUG_NET bool dev_check_flush(void) { - if (list_empty(this_cpu_ptr(&dev_flush_list))) + if (list_empty(bpf_net_ctx_get_dev_flush_list())) return false; __dev_flush(); return true; @@ -460,7 +459,7 @@ static void *__dev_map_lookup_elem(struct bpf_map *map, u32 key) static void bq_enqueue(struct net_device *dev, struct xdp_frame *xdpf, struct net_device *dev_rx, struct bpf_prog *xdp_prog) { - struct list_head *flush_list = this_cpu_ptr(&dev_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_dev_flush_list(); struct xdp_dev_bulk_queue *bq = this_cpu_ptr(dev->xdp_bulkq); if (unlikely(bq->count == DEV_MAP_BULK_SIZE)) @@ -1160,15 +1159,11 @@ static struct notifier_block dev_map_notifier = { static int __init dev_map_init(void) { - int cpu; - /* Assure tracepoint shadow struct _bpf_dtab_netdev is in sync */ BUILD_BUG_ON(offsetof(struct bpf_dtab_netdev, dev) != offsetof(struct _bpf_dtab_netdev, dev)); register_netdevice_notifier(&dev_map_notifier); - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(&per_cpu(dev_flush_list, cpu)); return 0; } diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 7d1c0986f9bb3..ed062e0383896 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -35,8 +35,6 @@ #define TX_BATCH_SIZE 32 #define MAX_PER_SOCKET_BUDGET (TX_BATCH_SIZE) -static DEFINE_PER_CPU(struct list_head, xskmap_flush_list); - void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool) { if (pool->cached_need_wakeup & XDP_WAKEUP_RX) @@ -372,7 +370,7 @@ static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) { - struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_xskmap_flush_list(); int err; err = xsk_rcv(xs, xdp); @@ -387,7 +385,7 @@ int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) void __xsk_map_flush(void) { - struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list); + struct list_head *flush_list = bpf_net_ctx_get_xskmap_flush_list(); struct xdp_sock *xs, *tmp; list_for_each_entry_safe(xs, tmp, flush_list, flush_node) { @@ -399,7 +397,7 @@ void __xsk_map_flush(void) #ifdef CONFIG_DEBUG_NET bool xsk_map_check_flush(void) { - if (list_empty(this_cpu_ptr(&xskmap_flush_list))) + if (list_empty(bpf_net_ctx_get_xskmap_flush_list())) return false; __xsk_map_flush(); return true; @@ -1772,7 +1770,7 @@ static struct pernet_operations xsk_net_ops = { static int __init xsk_init(void) { - int err, cpu; + int err; err = proto_register(&xsk_proto, 0 /* no slab */); if (err) @@ -1790,8 +1788,6 @@ static int __init xsk_init(void) if (err) goto out_pernet; - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(&per_cpu(xskmap_flush_list, cpu)); return 0; out_pernet: