From nobody Mon Dec 1 23:11:23 2025 Received: from out-188.mta0.migadu.com (out-188.mta0.migadu.com [91.218.175.188]) (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 D0392303CA4 for ; Wed, 26 Nov 2025 14:52:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.188 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764168744; cv=none; b=c/RnvqdGXCaloZz5yAZvISS8rIPEXCNLETMj3GIjlcP9XKct6HTVNpg+c48Ge+6LCb3/W33GvC6QIaVEvD1eUKAEkbVePnoQzrBwnfoP0Th95T7P28edkm++7LVJC50CewXgVyq+guvwv0mIakZ9f9sHk8Xy2PAkmukph+qO4RU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764168744; c=relaxed/simple; bh=LlYYr6YXrR6QEPCnnQAYyWnfYGASwCRYkM8mkTO03Pw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CAVtf3HAiFJMEmIAtlyYB/Zm4vo8q8eiy+tji+P1nl8OfBmOBPL2+Ywzw7AEtp9qVl2lHUUHHIvPl/pZzdM6EgCtp0XHjs/kZ6fdpDOsGbu2A2Mg2ejAFMaiYPDliRdZ3P0F8H/dPMvo1uODo02yX0xKUw3P8O5cStdTojQMmq4= 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=Gqp8BOey; arc=none smtp.client-ip=91.218.175.188 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="Gqp8BOey" 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=1764168740; 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=X2X+KLzyvJwhZKKjugRp6VQbzHu5EbCujgdbtaP+foU=; b=Gqp8BOeyOmHFE2sY2163AstDWBoBdYtg7wJBoMjHPAuju8qBi3Ggej9OzDuM0+XEdoh+TH bR+Kwr+pV9jTZQKH6+ZDEsPUbKSPmL0cd3rjWVRrdDxmwCTZAdbMTAZSFeMKEyEYSMA7BY sz2GVhI1GmzjP2cxvGgyJwNFhsSFfW8= 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, martin.lau@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, shuah@kernel.org, kerneljasonxing@gmail.com, chen.dylane@linux.dev, willemb@google.com, paul.chaignon@gmail.com, a.s.protopopov@gmail.com, memxor@gmail.com, yatsenko@meta.com, tklauser@distanz.ch, leon.hwang@linux.dev, kernel-patches-bot@fb.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v12 5/7] bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_cgroup_storage maps Date: Wed, 26 Nov 2025 22:50:37 +0800 Message-ID: <20251126145039.15715-6-leon.hwang@linux.dev> In-Reply-To: <20251126145039.15715-1-leon.hwang@linux.dev> References: <20251126145039.15715-1-leon.hwang@linux.dev> 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 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" 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 | 4 ++-- include/linux/bpf.h | 1 + kernel/bpf/local_storage.c | 23 ++++++++++++++++++----- kernel/bpf/syscall.c | 2 +- 4 files changed, 22 insertions(+), 8 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index aedf573bdb42..013f4db9903f 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -172,7 +172,7 @@ 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 *ma= p); =20 -int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *v= alue); +int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *v= alue, u64 flags); int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key, void *value, u64 flags); =20 @@ -467,7 +467,7 @@ static inline struct bpf_cgroup_storage *bpf_cgroup_sto= rage_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 f79d2ae27335..9e756db5e132 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -3835,6 +3835,7 @@ static inline bool bpf_map_supports_cpu_flags(enum bp= f_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 2ab4b60ffe61..1ccbf28b2ad9 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -180,7 +180,7 @@ static long cgroup_storage_update_elem(struct bpf_map *= map, void *key, } =20 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 =3D map_to_storage(_map); struct bpf_cgroup_storage *storage; @@ -198,11 +198,17 @@ int bpf_percpu_cgroup_storage_copy(struct bpf_map *_m= ap, void *key, * access 'value_size' of them, so copying rounded areas * will not leak any kernel data */ + if (map_flags & BPF_F_CPU) { + cpu =3D map_flags >> 32; + copy_map_value(_map, value, per_cpu_ptr(storage->percpu_buf, cpu)); + goto unlock; + } size =3D round_up(_map->value_size, 8); for_each_possible_cpu(cpu) { copy_map_value_long(_map, value + off, per_cpu_ptr(storage->percpu_buf, = cpu)); off +=3D size; } +unlock: rcu_read_unlock(); return 0; } @@ -212,10 +218,11 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *= _map, void *key, { struct bpf_cgroup_storage_map *map =3D map_to_storage(_map); struct bpf_cgroup_storage *storage; - int cpu, off =3D 0; + void *val; u32 size; + int cpu; =20 - if (map_flags !=3D BPF_ANY && map_flags !=3D BPF_EXIST) + if ((u32)map_flags & ~(BPF_ANY | BPF_EXIST | BPF_F_CPU | BPF_F_ALL_CPUS)) return -EINVAL; =20 rcu_read_lock(); @@ -231,11 +238,17 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *= _map, void *key, * returned or zeros which were zero-filled by percpu_alloc, * so no kernel data leaks possible */ + if (map_flags & BPF_F_CPU) { + cpu =3D map_flags >> 32; + copy_map_value(_map, per_cpu_ptr(storage->percpu_buf, cpu), value); + goto unlock; + } size =3D round_up(_map->value_size, 8); for_each_possible_cpu(cpu) { - copy_map_value_long(_map, per_cpu_ptr(storage->percpu_buf, cpu), value += off); - off +=3D size; + val =3D (map_flags & BPF_F_ALL_CPUS) ? value : value + size * cpu; + copy_map_value(_map, per_cpu_ptr(storage->percpu_buf, cpu), val); } +unlock: rcu_read_unlock(); return 0; } diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 94ac63b1115f..d8c2336124b6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -320,7 +320,7 @@ static int bpf_map_copy_value(struct bpf_map *map, void= *key, void *value, } else if (map->map_type =3D=3D BPF_MAP_TYPE_PERCPU_ARRAY) { err =3D bpf_percpu_array_copy(map, key, value, flags); } else if (map->map_type =3D=3D BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { - err =3D bpf_percpu_cgroup_storage_copy(map, key, value); + err =3D bpf_percpu_cgroup_storage_copy(map, key, value, flags); } else if (map->map_type =3D=3D BPF_MAP_TYPE_STACK_TRACE) { err =3D bpf_stackmap_extract(map, key, value, false); } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) { --=20 2.51.2