From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-179.mta0.migadu.com (out-179.mta0.migadu.com [91.218.175.179]) (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 983731C5D77 for ; Wed, 27 Aug 2025 16:45:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756313157; cv=none; b=BqdJGdRSnBYZmRcIKTM9NWLEJiJ18bPsYyE4pMsRP4h9K785MqSBTTXtb8jV83lF92kL7Oa+GNVnNYJcMjTwRUhWW/eQlLOEJneiVvR3Mq0yj0GLZqFwea4xW08/D1l5ni3/d48+YI85G1nOQyfcQZJrFc5/49JUvcBk2dP78J0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756313157; c=relaxed/simple; bh=8ku6OEf3d2CGydMHBVekWKHxIT6MsuCxCv9N7vpHGMg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O+CfJjETECR2u0Huje8dMybIc9udBXaN7qkt5Tyo86ZGANk958OarkLTdwbZQGmpvj/Dbj9k0BwzBnYWiVrZaK46Pm8aPwIqRgHquq4usOoynRiUCdsFTB1eA+MxJnKeaspLHmxthUFerZDoNw7Qs9Ydd3b26FgoqxlonzHXNAk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=qUOP5tMp; arc=none smtp.client-ip=91.218.175.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="qUOP5tMp" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1756313153; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/9AOIpzvJMdSXDof0KsRVALWfiePVkaZdf4ew2cKKio=; b=qUOP5tMpuDobmVHrDeWWhTS9NdG5c5NG53TplBaG+oZJzF81XsX/tzAGGneeUpw3c7Wrty +IN3QkgK5PZ58OmyhtpH96ky2Pd5hTiwqi4OTVhSNbrYnEBhBJ+0JcwaujouTBSpfj5gWn Z0cD9Aog34sHK/8MHPozKQ5drr7zLho= From: Leon Hwang To: bpf@vger.kernel.org Cc: ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, jolsa@kernel.org, yonghong.song@linux.dev, song@kernel.org, eddyz87@gmail.com, dxu@dxuuu.xyz, deso@posteo.net, leon.hwang@linux.dev, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v4 5/7] bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags for percpu_cgroup_storage maps Date: Thu, 28 Aug 2025 00:45:07 +0800 Message-ID: <20250827164509.7401-6-leon.hwang@linux.dev> In-Reply-To: <20250827164509.7401-1-leon.hwang@linux.dev> References: <20250827164509.7401-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Introduce BPF_F_ALL_CPUS flag support for percpu_cgroup_storage maps to allow updating values for all CPUs with a single value for update_elem API. Introduce BPF_F_CPU flag support for percpu_cgroup_storage maps to allow: * update value for specified CPU for update_elem API. * lookup value for specified CPU for lookup_elem API. The BPF_F_CPU flag is passed via map_flags along with embedded cpu info. Signed-off-by: Leon Hwang --- include/linux/bpf-cgroup.h | 5 +++-- include/linux/bpf.h | 1 + kernel/bpf/local_storage.c | 42 ++++++++++++++++++++------------------ kernel/bpf/syscall.c | 2 +- 4 files changed, 27 insertions(+), 23 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index aedf573bdb426..1cb28660aa866 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -172,7 +172,8 @@ void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage, void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage); int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux, struct bpf_map *map); -int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value); +int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value, + u64 flags); int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key, void *value, u64 flags); @@ -467,7 +468,7 @@ static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc( static inline void bpf_cgroup_storage_free( struct bpf_cgroup_storage *storage) {} static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, - void *value) { + void *value, u64 flags) { return 0; } static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map, diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c120b00448a13..2d67af3e7f870 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -3765,6 +3765,7 @@ static inline bool bpf_map_supports_cpu_flags(enum bpf_map_type map_type) case BPF_MAP_TYPE_PERCPU_ARRAY: case BPF_MAP_TYPE_PERCPU_HASH: case BPF_MAP_TYPE_LRU_PERCPU_HASH: + case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: return true; default: return false; diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index c93a756e035c0..31b146cf8f48e 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -180,18 +180,22 @@ static long cgroup_storage_update_elem(struct bpf_map *map, void *key, } int bpf_percpu_cgroup_storage_copy(struct bpf_map *_map, void *key, - void *value) + void *value, u64 map_flags) { struct bpf_cgroup_storage_map *map = map_to_storage(_map); struct bpf_cgroup_storage *storage; - int cpu, off = 0; u32 size; + int err; + + err = bpf_map_check_cpu_flags(map_flags, false); + if (err) + return err; rcu_read_lock(); storage = cgroup_storage_lookup(map, key, false); if (!storage) { - rcu_read_unlock(); - return -ENOENT; + err = -ENOENT; + goto unlock; } /* per_cpu areas are zero-filled and bpf programs can only @@ -199,13 +203,10 @@ int bpf_percpu_cgroup_storage_copy(struct bpf_map *_map, void *key, * will not leak any kernel data */ size = round_up(_map->value_size, 8); - for_each_possible_cpu(cpu) { - bpf_long_memcpy(value + off, - per_cpu_ptr(storage->percpu_buf, cpu), size); - off += size; - } + bpf_percpu_copy_to_user(_map, storage->percpu_buf, value, size, map_flags); +unlock: rcu_read_unlock(); - return 0; + return err; } int bpf_percpu_cgroup_storage_update(struct bpf_map *_map, void *key, @@ -213,17 +214,21 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *_map, void *key, { struct bpf_cgroup_storage_map *map = map_to_storage(_map); struct bpf_cgroup_storage *storage; - int cpu, off = 0; u32 size; + int err; - if (map_flags != BPF_ANY && map_flags != BPF_EXIST) + if ((u32)map_flags & ~(BPF_ANY | BPF_EXIST | BPF_F_CPU | BPF_F_ALL_CPUS)) return -EINVAL; + err = bpf_map_check_cpu_flags(map_flags, true); + if (err) + return err; + rcu_read_lock(); storage = cgroup_storage_lookup(map, key, false); if (!storage) { - rcu_read_unlock(); - return -ENOENT; + err = -ENOENT; + goto unlock; } /* the user space will provide round_up(value_size, 8) bytes that @@ -233,13 +238,10 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *_map, void *key, * so no kernel data leaks possible */ size = round_up(_map->value_size, 8); - for_each_possible_cpu(cpu) { - bpf_long_memcpy(per_cpu_ptr(storage->percpu_buf, cpu), - value + off, size); - off += size; - } + bpf_percpu_copy_from_user(_map, storage->percpu_buf, value, size, map_flags); +unlock: rcu_read_unlock(); - return 0; + return err; } static int cgroup_storage_get_next_key(struct bpf_map *_map, void *key, diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 91ab9bdd1da38..0c88d7f6f1491 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -318,7 +318,7 @@ static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_copy(map, key, value, flags); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { - err = bpf_percpu_cgroup_storage_copy(map, key, value); + err = bpf_percpu_cgroup_storage_copy(map, key, value, flags); } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { err = bpf_stackmap_copy(map, key, value); } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { -- 2.50.1