From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-189.mta0.migadu.com (out-189.mta0.migadu.com [91.218.175.189]) (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 8595819E97B for ; Sun, 30 Nov 2025 05:43:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.189 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764481439; cv=none; b=qzS5yuprZPpVzfc3IEaNP+xwe2lc6EvT8D6Qhw8v96VBurSoZ3dSK8/K+5qem44L44iuBe8rELb+V1fxQlm/u7Ub3y4ZkcqHW1KPXMtJO1lxV7YFs37I+3S4PQ+qYEFZmVE9bAJUUkByBIgNblvaQ2jCmukQb1bojh1GyxHH1PE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764481439; c=relaxed/simple; bh=Bog9QjhJRE8AvWPr4Z8m0BPiFb8t3jqwIJ2OT7Fd3nU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=FsBxm5FL5n0qPDltiK8Ts5Eg4HYynbVJpZXIr7dFKYkk3vA1nMOfoaZUbKk7s//U0pVOW+l4X4aA+YxHobgB0Jv6Whxt6HrMd+ASyBlL18rSNuWlMdNkyWJywid5EG1deVaN1Kxo8jXD6hbVGv2TIZ6Fn7JUlIHwFFnIVei5iDk= 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=hhHMeX4M; arc=none smtp.client-ip=91.218.175.189 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="hhHMeX4M" Message-ID: <3e672e64-c03d-4129-ac13-13a45135b0f1@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1764481435; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=c430BRCmGanH/MPJGuwwdlsIkfObJWBE5PMd1Ua8cwU=; b=hhHMeX4MWnzBiS1u4mfLroXP8C01xjSonDXGnWALgzqG72f/4u6B772DvGRiPGmSwlPQgd YVcLJoeDzBRVKsVXG70I+eV/W7biPmQtSJT5lo2n43g8cjp22d3fHKzhN4y8RyMDaQ092c PDhBb8vA8/Sp5PhK43WcU9Qr/iLz7qI= Date: Sun, 30 Nov 2025 13:43:51 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] hung_task: Migrate hung_task_detect_count to sysfs Content-Language: en-US To: Aaron Tomlin Cc: linux-kernel@vger.kernel.org, mhiramat@kernel.org, akpm@linux-foundation.org, gregkh@linuxfoundation.org, Petr Mladek References: <20251129235159.1227977-1-atomlin@atomlin.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Lance Yang In-Reply-To: <20251129235159.1227977-1-atomlin@atomlin.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Hi Aaron, Thanks for the patch. On 2025/11/30 07:51, Aaron Tomlin wrote: > The hung_task_detect_count metric, which tracks the cumulative number of > tasks detected as hung since boot, is currently exposed via the legacy > /proc/sys/kernel/hung_task_detect_count sysctl file. > > Migrate this metric to a read-only file in the /sys/kernel/ hierarchy: > /sys/kernel/hung_task_detect_count. The sysctl file is removed, and the > metric is now controlled by the CONFIG_SYSFS Kconfig option. Emm, I don't think we should do this :) Removing the sysctl file is going to break userspace tools that currently read it ... And, yeah, while moving read-only stats to sysfs makes sense on paper, is it really worth the churn? Since we'd likely have to keep the old sysctl file anyway for backward compatibility, we'd just end up maintaining two interfaces fo the exact same counter :) [...] Thanks anyway, Lance