From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 696DFF4644A for ; Mon, 16 Mar 2026 10:43:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9886B6B018D; Mon, 16 Mar 2026 06:43:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 972F86B018E; Mon, 16 Mar 2026 06:43:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 874F16B018F; Mon, 16 Mar 2026 06:43:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 7344C6B018D for ; Mon, 16 Mar 2026 06:43:41 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 0EF011401A8 for ; Mon, 16 Mar 2026 10:43:41 +0000 (UTC) X-FDA: 84551590242.01.F9F8311 Received: from mail-wm1-f74.google.com (mail-wm1-f74.google.com [209.85.128.74]) by imf12.hostedemail.com (Postfix) with ESMTP id 49E994000B for ; Mon, 16 Mar 2026 10:43:39 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=google.com header.s=20251104 header.b=eYFgQzJF; spf=pass (imf12.hostedemail.com: domain of 32d63aQkKCMoq1ysu7Ex1w44w1u.s421y3AD-220Bqs0.47w@flex--aliceryhl.bounces.google.com designates 209.85.128.74 as permitted sender) smtp.mailfrom=32d63aQkKCMoq1ysu7Ex1w44w1u.s421y3AD-220Bqs0.47w@flex--aliceryhl.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1773657819; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=aIsjm9vE54z8tUJ1wyvdDm1uLSUX2YtWlUueHA6I6BA=; b=ad2ngCblACyrYfkyjfUaflClFVaBCj2CzVh4hjDZcwXKVyf/3HmL5Yw9AFUSCHgTacVIFi LgirhyrJFVyFK11Dh06sYkufBRuONWo3KFeU/xHaCrwQD+8u5DwLxok1FRujwhE31zAojM oyvE4HXf9Qvlp4834EP/ZpZm7U1w258= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=google.com header.s=20251104 header.b=eYFgQzJF; spf=pass (imf12.hostedemail.com: domain of 32d63aQkKCMoq1ysu7Ex1w44w1u.s421y3AD-220Bqs0.47w@flex--aliceryhl.bounces.google.com designates 209.85.128.74 as permitted sender) smtp.mailfrom=32d63aQkKCMoq1ysu7Ex1w44w1u.s421y3AD-220Bqs0.47w@flex--aliceryhl.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1773657819; a=rsa-sha256; cv=none; b=uqnyeR7CH1o5OzedBCT6/yvrGXKR3PF6Pf8U/iNZQpsP7VOEpvaD1H2bhc4WVQ6upS7ct/ WlUbPXNIDkVA+5ewj1YemCLUSW9SijrBeoJ0TOD51qqioGLjM45rfTdZpvbD6tpQt3z80i xYzq0d2mJrdWbJxxlFkBMLGvyN50hRE= Received: by mail-wm1-f74.google.com with SMTP id 5b1f17b1804b1-48544725bdeso57296365e9.2 for ; Mon, 16 Mar 2026 03:43:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1773657818; x=1774262618; darn=kvack.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=aIsjm9vE54z8tUJ1wyvdDm1uLSUX2YtWlUueHA6I6BA=; b=eYFgQzJF3TGrVDiN/m9vc5EMnBXQV+RvglT3Vnkmu5aOMKuD6di89inY7732UXRohI t6f/eo/LEcCMK8CH+vAXhg/u7yI6+kGcjPolZxHkEyL3jNyDA6sq0PCLBmB017Phki+A 00UuT4nu99Y/shvQZFhSzpJaojed6WRH8y/NQzEBpvBMW9YcnoIZJbrSrQHry4IPmJw8 XCb6BHRknn4nI4XQ5lWx+BjF/QmdL1mHF1BMg/X+RDb/sSrbCSfNN9nVE8igGTleiA4M ybxmalBM5vAnL478pWtEpBywXCTre/UXm/b3m4fxa1SrcO1pALUUkiq/g6Ur+Vu0/0BH JDUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773657818; x=1774262618; 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=aIsjm9vE54z8tUJ1wyvdDm1uLSUX2YtWlUueHA6I6BA=; b=AyzEO4MGBnYFkVKlg2tBc5c5J/jXY4GJWkymDYV1NERoXdjO5uWoQZeU5PzKr15eCV Q7/vY5Sfyjj/G0XYJxyJILClsvOQhzZbuhEA7wC/6e3Js/P4GMzLJJGhOmkTzBPMtfmF KmUaDwebdMjZtV1qVFEYw90TrIWWrx3fuVeFkYKLgImEQ+d8vdPEIcl/WQhnWjAiSy5f r6D1jBc5izluopzlLNuRDXtzlfD/gU3ExLUkpqF0i9X8vIph5uUHO5PzRy2wv6M3x0OU ghFMXG43/Ir50ZeWWWPqR5PZlkK2XcGffV7sHgJ++jns2mfWNAzTWFGIzs0NBRk4hHhE zobw== X-Forwarded-Encrypted: i=1; AJvYcCXkiCRrHEG8VySW2mouXuVrYGhn+C75EB+G3I56grh/rtpByDJaDIm7wh6aae7R4OXGWHIYesuaNg==@kvack.org X-Gm-Message-State: AOJu0YzcH+JiUMK9vjDJj9M+bLlnp+whJJ46sD4owPIQizS+yB6wtzfj QTqVFkVMw8Nsg5wGHzfG5JxpicfTBs9oi2WraD/z/ncAFrCBkhyNfRxhl7kxOwxpKn/EFs+Y02y WyE4t+MXCBLC5ZXX5sA== X-Received: from wmno9.prod.google.com ([2002:a05:600c:1649:b0:485:38ca:51c9]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1e8c:b0:485:3e00:9440 with SMTP id 5b1f17b1804b1-4855670c296mr200273645e9.24.1773657817662; Mon, 16 Mar 2026 03:43:37 -0700 (PDT) Date: Mon, 16 Mar 2026 10:43:36 +0000 In-Reply-To: <20260216-rnull-v6-19-rc5-send-v1-15-de9a7af4b469@kernel.org> Mime-Version: 1.0 References: <20260216-rnull-v6-19-rc5-send-v1-0-de9a7af4b469@kernel.org> <20260216-rnull-v6-19-rc5-send-v1-15-de9a7af4b469@kernel.org> Message-ID: Subject: Re: [PATCH 15/79] block: rnull: add `use_per_node_hctx` config option From: Alice Ryhl To: Andreas Hindborg Cc: Boqun Feng , Jens Axboe , Miguel Ojeda , Gary Guo , "=?utf-8?B?QmrDtnJu?= Roy Baron" , Benno Lossin , Trevor Gross , Danilo Krummrich , FUJITA Tomonori , Frederic Weisbecker , Lyude Paul , Thomas Gleixner , Anna-Maria Behnsen , John Stultz , Stephen Boyd , Lorenzo Stoakes , "Liam R. Howlett" , linux-block@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset="utf-8" X-Rspamd-Queue-Id: 49E994000B X-Stat-Signature: j5iu1cz55bjci6qtjyf4c64u8jhoncdq X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1773657819-753098 X-HE-Meta: U2FsdGVkX1/sbnuzAhL4tDLK0rZ+bz+02oxwlUngPa+jJY3RT2B+KHst9ER0JOrgqJs4JPzPkbjQhGfQR+3HMfMGGLuJCyX4+EOQe8tAGXb5m6XabdP9nrfPfH2XV0wyJHV3T5s+hJltksqTQPTi8ad2mIO2VizVSf937J18wx/XrQ9aP73VBl+JNPu6ya4QghYldS1x6/N+O5jA5LlrQoQiUmtz8Y49zcRJOjJxivM6shxPqGOjfOHSOEssCZ+KbfDUOOc4T1IK3ufr9zW4l0ty8b5y9vHu0zocNMwLpUKqMI1uNYvsM9IINGhx9QNZSxQx4WkbvHEi6yYTJBIXJ6tfTqB9rho5a2pPT/ko9maEHd3XlR3oHUB5Vfky0XjoNwxRWxs3L4DBoFyV2VzT7b7i0Vqj2h1gw9zOltqSTrhfbw6I6xt+nhsekv0SuyBX00w0Ng4SBijwrGoafNyVqVCMOvyLxvkObDfCjfJZznkMT5Nbesp2VE2DJ3mvVmbmoYWxCQjZ9cmzbrHY7vXDBE/ZKGtb7ntbRjI0NKRONAFIpUhqNz/8ON/LJoSSXqsUgZAR158ttG+qJ1ZcBQ1wkYevT8eexszIvcjS5GXi16lm5kk7fykKtaeobjjYMNUS9TWMGifMygDn576Dzs+iGlsydoV5FsSwxDmldj5k14zfuXphQijFAv/0GTxtHhZSyp12xUWCRiiMFzl6EDH+JtGY4xaDDdkB1b2LH6TeaG3pC01xxh+ZfTgNFU/056QOOdsbYAJ+DvHFcFuSWPSb3RLgVlTExJnlltC+uXsboqLu8rnaUhgwhTTOD6DHVZkJS/l1c2kYOphjkZHSUP8S6qYKnz2du8df5HPW+fM93MXZ3vH3eQvnEXWNvENJPKt483Q8KRqJ0+frtwymwt9lc3N48/pkzYIebOzvQzZ/u8iiiFY/A7MGm7QzxOxy2sAxfrMfOXmUtyxjYxeySgy C6vFFipR 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Feb 16, 2026 at 12:35:02AM +0100, Andreas Hindborg wrote: > Add a configfs attribute to enable per-NUMA-node hardware contexts. > When enabled, the driver creates one hardware queue per NUMA node > instead of the default configuration. > > Signed-off-by: Andreas Hindborg This and other patches make me think that module parameters should have value() return a copy of the value (and require Copy). For non-copy types, there can be a separate value_ref() method. You would avoid *so* many asterisks by doing that. > +configfs_attribute!(DeviceConfig, 8, > + show: |this, page| show_field( > + this.data.lock().submit_queues == kernel::num_online_nodes(), page > + ), > + store: |this, page| store_with_power_check(this, page, |this, page| { > + let value = core::str::from_utf8(page)? > + .trim() > + .parse::() > + .map_err(|_| kernel::error::code::EINVAL)? > + != 0; > + > + if value { > + this.data.lock().submit_queues *= kernel::num_online_nodes(); > + } kstrtobool again. Also, this is *multiplying* the existing submit_queues value by the number of NUMA nodes? > + use_per_node_hctx: u8 { > + default: 0, > + description: > + "Use per-node allocation for hardware context queues, 0-false, 1-true. Default: 0-false", > + }, formatting (rustfmt ignores macros) Alice