From patchwork Wed Feb 7 17:10:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoann Congal X-Patchwork-Id: 770801 Received: from mail-wm1-f54.google.com (mail-wm1-f54.google.com [209.85.128.54]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 39CD7823B4 for ; Wed, 7 Feb 2024 17:10:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.54 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707325852; cv=none; b=FEGpP1eYPOm28RbTIfGRoXdtCpAc+XemdCcSCkHC+jtmZslnkb5YU4Q+7xkML8or1dkM+NebPPCkEZRMLstulLdNRgPJ7fS8C5hcDKBbRDmtJ5ev8v3mcEAf8Inw6K39phAeI3GGJKKTniN7LUeOBB9KQOCAeOZkcxZaRhu0GX8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707325852; c=relaxed/simple; bh=PZg3QWq+/GKgfZZA2qyqx39P/kRDLKfoOfmCw8uE3uc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=auRKWFnEWzZcwXgeTZlnyymGg26tqYFPKPwY/nK7V8MQwS5c2sCSPykpnMj74GMM4c7baNoHg0n3GSwto9Pyij5qVsSdUHSroV59B7jTGDsNeBikwxhQs1YTRQFTxyErKsW+Y01u16rfRJN53BaNqfJ0DxCNpMauMg5F/SQcwSw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=smile.fr; spf=pass smtp.mailfrom=smile.fr; dkim=pass (2048-bit key) header.d=smile-fr.20230601.gappssmtp.com header.i=@smile-fr.20230601.gappssmtp.com header.b=JyCIYQbZ; arc=none smtp.client-ip=209.85.128.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=smile.fr Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=smile.fr Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=smile-fr.20230601.gappssmtp.com header.i=@smile-fr.20230601.gappssmtp.com header.b="JyCIYQbZ" Received: by mail-wm1-f54.google.com with SMTP id 5b1f17b1804b1-4102a186cfbso1014855e9.2 for ; Wed, 07 Feb 2024 09:10:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=smile-fr.20230601.gappssmtp.com; s=20230601; t=1707325847; x=1707930647; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=JGAprqtgwfmvAPo8XwmHq4MOLLyHp0qoLOC+fnp28mc=; b=JyCIYQbZG3crh+1P4QYiSzc1BeeDI2f25cbQj9t9pn8weFA8c76ctON0v31zib14uj UIjYGm2vZo0BVTOVvW8AI5Ia1Uk0TU/p7I/RrIX/1IILeKzuGdUx2IKVlPFTCZOPmnme yJshfaDn79tPPU/2m6gAlWOp4vHffwxjDp/2sSh4yvbHdIzZtazmr5Rr84gOSWZKXnK5 3kDZRq4McbOIp5IweafGlu5Sx99iuDukod63FHf8KJ9df1cQ0V99I3xyYvFCDVv109Nn VbxVlWXkxxVjkOefmxsPJHkWfeM3VByI5dOtQ0PLIIvE0ivD5BZuSbyS0QGZEUYmDogn 7Z9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707325847; x=1707930647; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=JGAprqtgwfmvAPo8XwmHq4MOLLyHp0qoLOC+fnp28mc=; b=leH25ygI25V4mmh9f894Iz3mHrfE6h29UWNEUtlTVnam1qFJOyqt/V+y1Lgt3o8jsM yXOAn4Pdt0WMBLmZb9RuepscYFQzOfyyXVQ3xegr+1qPx1N/2yDUeIrwpa+dyU4i7oFk NoHwGbeV8P39cZYbaslWvKFnKVFYNYeO+CSz/jdQ2c/AifZH2XRxKY0AiDe0wUbNicUH pdI6q/Jor7k8YuFVjiiKl6Z4OnNcOMzpLEl+xYozinALY22lFhIo686uZunGUqB4ykcO WhFL+1jpfF7lhIUDHCpkJXSwxKah+qK70J3JBNQTvU4TgZc4Lifzgx0aLYbURw+bV6hN gbRw== X-Gm-Message-State: AOJu0Yz4o4uwTpyvS7UU9figFYaU4Stx14zRRvAsF6XX2yL9UPgsqdOY 5rqL9A+9bZ2U3o8AH5knkqes8AM8GfamGcIT38+Db/6lqlOSvvKv+yS4lTb/xv8= X-Google-Smtp-Source: AGHT+IEP4HUse3caW9WxO2ULwF9rR3ZtBHAYEAEuRsB20KeNbbZ44lTBpuwNyZ1EZ+H0FTfcKuPYog== X-Received: by 2002:a5d:598a:0:b0:33b:47cf:323b with SMTP id n10-20020a5d598a000000b0033b47cf323bmr5501964wri.9.1707325847517; Wed, 07 Feb 2024 09:10:47 -0800 (PST) X-Forwarded-Encrypted: i=1; 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 Received: from P-ASN-ECS-830T8C3.idf.intranet (static-css-ccs-204145.business.bouyguestelecom.com. [176.157.204.145]) by smtp.gmail.com with ESMTPSA id u14-20020a05600c19ce00b0040fdf2832desm2645584wmq.12.2024.02.07.09.10.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Feb 2024 09:10:46 -0800 (PST) From: Yoann Congal To: linux-fsdevel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, x86@kernel.org Cc: =?utf-8?q?Andr=C3=A9_Almeida?= , Borislav Petkov , Darren Hart , Dave Hansen , Davidlohr Bueso , Geert Uytterhoeven , Greg Kroah-Hartman , "H . Peter Anvin" , Ingo Molnar , Jiri Slaby , John Ogness , Josh Triplett , Masahiro Yamada , Matthew Wilcox , Peter Zijlstra , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , Willem de Bruijn , Yoann Congal , Vegard Nossum Subject: [PATCH v5 1/3] printk: Fix LOG_CPU_MAX_BUF_SHIFT when BASE_SMALL is enabled Date: Wed, 7 Feb 2024 18:10:18 +0100 Message-Id: <20240207171020.41036-2-yoann.congal@smile.fr> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240207171020.41036-1-yoann.congal@smile.fr> References: <20240207171020.41036-1-yoann.congal@smile.fr> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 LOG_CPU_MAX_BUF_SHIFT default value depends on BASE_SMALL: config LOG_CPU_MAX_BUF_SHIFT default 12 if !BASE_SMALL default 0 if BASE_SMALL But, BASE_SMALL is a config of type int and "!BASE_SMALL" is always evaluated to true whatever is the value of BASE_SMALL. This patch fixes this by using the correct conditional operator for int type : BASE_SMALL != 0. Note: This changes CONFIG_LOG_CPU_MAX_BUF_SHIFT=12 to CONFIG_LOG_CPU_MAX_BUF_SHIFT=0 for BASE_SMALL defconfigs, but that will not be a big impact due to this code in kernel/printk/printk.c: /* by default this will only continue through for large > 64 CPUs */ if (cpu_extra <= __LOG_BUF_LEN / 2) return; Systems using CONFIG_BASE_SMALL and having 64+ CPUs should be quite rare. John Ogness (printk reviewer) wrote: > For printk this will mean that BASE_SMALL systems were probably > previously allocating/using the dynamic ringbuffer and now they will > just continue to use the static ringbuffer. Which is fine and saves > memory (as it should). Petr Mladek (printk maintainer) wrote: > More precisely, it allocated the buffer dynamically when the sum > of per-CPU-extra space exceeded half of the default static ring > buffer. This happened for systems with more than 64 CPUs with > the default config values. Signed-off-by: Yoann Congal Reported-by: Geert Uytterhoeven Closes: https://lore.kernel.org/all/CAMuHMdWm6u1wX7efZQf=2XUAHascps76YQac6rdnQGhc8nop_Q@mail.gmail.com/ Reported-by: Vegard Nossum Closes: https://lore.kernel.org/all/f6856be8-54b7-0fa0-1d17-39632bf29ada@oracle.com/ Fixes: 4e244c10eab3 ("kconfig: remove unneeded symbol_empty variable") Reviewed-by: Petr Mladek Reviewed-by: Masahiro Yamada --- v3->v4: * Fix BASE_SMALL usage instead of switching to BASE_FULL because BASE_FULL will be removed in the next patches of this series. --- init/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index deda3d14135bb..d50ebd2a2ce42 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -734,8 +734,8 @@ config LOG_CPU_MAX_BUF_SHIFT int "CPU kernel log buffer size contribution (13 => 8 KB, 17 => 128KB)" depends on SMP range 0 21 - default 12 if !BASE_SMALL - default 0 if BASE_SMALL + default 0 if BASE_SMALL != 0 + default 12 depends on PRINTK help This option allows to increase the default ring buffer size