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{ "id": 2175244, "url": "http://patchwork.ozlabs.org/api/1.0/covers/2175244/?format=api", "project": { "id": 26, "url": "http://patchwork.ozlabs.org/api/1.0/projects/26/?format=api", "name": "Netfilter Development", "link_name": "netfilter-devel", "list_id": "netfilter-devel.vger.kernel.org", "list_email": "netfilter-devel@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null }, "msgid": "<20251217162744.352391-1-mkoutny@suse.com>", "date": "2025-12-17T16:27:32", "name": "[0/4] Use __counted_by for ancestor arrays", "submitter": { "id": 74126, "url": "http://patchwork.ozlabs.org/api/1.0/people/74126/?format=api", "name": "Michal Koutný", "email": "mkoutny@suse.com" }, "series": [ { "id": 485721, "url": "http://patchwork.ozlabs.org/api/1.0/series/485721/?format=api", "date": "2025-12-17T16:27:32", "name": "Use __counted_by for ancestor arrays", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/485721/mbox/" } ], "headers": { "Return-Path": "\n <netfilter-devel+bounces-10145-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "netfilter-devel@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=suse.com header.i=@suse.com header.a=rsa-sha256\n header.s=google header.b=UbGQDrg+;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c09:e001:a7::12fc:5321; helo=sto.lore.kernel.org;\n envelope-from=netfilter-devel+bounces-10145-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)", "smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com\n header.b=\"UbGQDrg+\"", "smtp.subspace.kernel.org;\n arc=none smtp.client-ip=209.85.128.52", "smtp.subspace.kernel.org;\n dmarc=pass (p=quarantine dis=none) header.from=suse.com", "smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=suse.com" ], "Received": [ "from sto.lore.kernel.org (sto.lore.kernel.org\n [IPv6:2600:3c09:e001:a7::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4dWfRD26z9z1xty\n\tfor <incoming@patchwork.ozlabs.org>; Thu, 18 Dec 2025 03:30:16 +1100 (AEDT)", "from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sto.lore.kernel.org (Postfix) with ESMTP id 2D37C302CBAF\n\tfor <incoming@patchwork.ozlabs.org>; Wed, 17 Dec 2025 16:30:13 +0000 (UTC)", "from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 010BE355038;\n\tWed, 17 Dec 2025 16:28:04 +0000 (UTC)", "from mail-wm1-f52.google.com (mail-wm1-f52.google.com\n [209.85.128.52])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id EC85D34D4C1\n\tfor <netfilter-devel@vger.kernel.org>; Wed, 17 Dec 2025 16:28:00 +0000 (UTC)", "by mail-wm1-f52.google.com with SMTP id\n 5b1f17b1804b1-47789cd2083so32819815e9.2\n for <netfilter-devel@vger.kernel.org>;\n Wed, 17 Dec 2025 08:28:00 -0800 (PST)", "from blackdock.suse.cz (nat2.prg.suse.com. 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Miller\" <davem@davemloft.net>,\n Simon Horman <horms@kernel.org>, John Fastabend <john.fastabend@gmail.com>,\n Johannes Weiner <hannes@cmpxchg.org>, Daniel Borkmann <daniel@iogearbox.net>,\n Andrii Nakryiko <andrii@kernel.org>, Tejun Heo <tj@kernel.org>,\n Josef Bacik <josef@toxicpanda.com>, Paolo Abeni <pabeni@redhat.com>,\n \"Gustavo A. R. Silva\" <gustavoars@kernel.org>,\n Pablo Neira Ayuso <pablo@netfilter.org>,\n Eduard Zingerman <eddyz87@gmail.com>, Yu Kuai <yukuai@fnnas.com>,\n Masami Hiramatsu <mhiramat@kernel.org>, Kees Cook <kees@kernel.org>,\n Jakub Kicinski <kuba@kernel.org>", "Subject": "[PATCH 0/4] Use __counted_by for ancestor arrays", "Date": "Wed, 17 Dec 2025 17:27:32 +0100", "Message-ID": "<20251217162744.352391-1-mkoutny@suse.com>", "X-Mailer": "git-send-email 2.52.0", "Precedence": "bulk", "X-Mailing-List": "netfilter-devel@vger.kernel.org", "List-Id": "<netfilter-devel.vger.kernel.org>", "List-Subscribe": "<mailto:netfilter-devel+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:netfilter-devel+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "Content-Type": "text/plain; charset=UTF-8", "Content-Transfer-Encoding": "8bit" }, "content": "The trick with utilizing space in cgroup_root for cgroup::ancetors flex\narray was an obstacle for kernel reworks for\n-Wflex-array-member-not-at-end.\n\nThe first patch fixes that, then I wanted to utilize __counted_by for\nthis flex array which required some more rework how cgroup level is\nevaluated.\n\nSimilar flex array is also in struct ioc_gq where it was tempting to\nsimply use __counted_by(level), however, this would be off-by-one as it\nhas semantics like cgroup's level (0 == root).\nProper adjustment for __counted_by() would either need similar\nlevel/ancestor helpers or abstracted macros for ancestors up/down\niterations.\n\nI only made a simple comment fixup since I'm not sure about benefit of\n__counted_by for structs that aren't sized based on direct user input.\n\nMichal Koutný (4):\n cgroup: Eliminate cgrp_ancestor_storage in cgroup_root\n cgroup: Introduce cgroup_level() helper\n cgroup: Use __counted_by for cgroup::ancestors\n blk-iocost: Correct comment ioc_gq::level\n\n block/bfq-iosched.c | 2 +-\n block/blk-iocost.c | 6 ++---\n include/linux/cgroup-defs.h | 43 +++++++++++++++++++----------------\n include/linux/cgroup.h | 18 ++++++++++++---\n include/trace/events/cgroup.h | 8 +++----\n kernel/bpf/helpers.c | 2 +-\n kernel/cgroup/cgroup.c | 9 ++++----\n net/netfilter/nft_socket.c | 2 +-\n 8 files changed, 53 insertions(+), 37 deletions(-)\n\n\nbase-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8" }