From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (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 A6EF53C555E; Wed, 11 Mar 2026 09:15:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773220510; cv=none; b=Sn+25s+mhgc9w06RjlFTVnuQX+n1ZclHBsUtUzBxJw49ClMEvRcxeDBrg4DHyaBZagpOkN3MPsw/lrE/GUI+JA/lT6Ak0pNPOUIlwkhVUwRcuOPqMk8pmJqt6HQVg+KoUexQoPq8C3kR/1LeQd3tNxuGhdslR6h73ZyJAmz5zZw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773220510; c=relaxed/simple; bh=gep9q6y8/u2CtlHp6ylZWa2AkWo3bjFyDR/+rL2T62U=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DZOzLryfOsaGItbniCAn/tBttD4H4jKQVMWiEDXyVyPyfNy26I/3tDPN5q3Q6EBsDxZofeFvndBmvzy9TcX7vPmZjpIQcJy8HAGlSdXm55CrI6s9o31QHMHb+1GCtx2L97YMFkQKrAPdCe03tQObVuZt0+V4BLH7Y80g7lhVcwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=fyj1QwQ1; arc=none smtp.client-ip=192.198.163.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="fyj1QwQ1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1773220502; x=1804756502; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=gep9q6y8/u2CtlHp6ylZWa2AkWo3bjFyDR/+rL2T62U=; b=fyj1QwQ1kb+fApAiN9J1rZmT3PWbqvq/EBfN8zosGObdTh0BTSw9K0id dLzqKszIOEkLd6YEO2DsxnVfYvTrloqv7sScLUEnx3jUii7JcVuMyKZ+C 1GOhfLASAYXzZvIQqt6m72sCwqtIwrxulVxtk7mLeG6hCrXxbE4SO612x 5f2hx4VyVpg5qd/WeI48kCUiVNODa/zh/1QqVCSkjSStDdu6D5T/+Qw1d WbsAFtJv1/+D/xWL/2EwdSPo7wi19OkZHg4gyJVeEm9LxVXrruWRTneU7 12iKnG8CaUeSK0WTzITTVzuHHr0sBw6OFFmBl3VylsPKX6mseBkfp2xnt Q==; X-CSE-ConnectionGUID: qGDmvqK8S+uUMD+nWT4KUQ== X-CSE-MsgGUID: sDirN69xTDGjz0Z/Cv8K7A== X-IronPort-AV: E=McAfee;i="6800,10657,11725"; a="61855826" X-IronPort-AV: E=Sophos;i="6.23,113,1770624000"; d="scan'208";a="61855826" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2026 02:14:58 -0700 X-CSE-ConnectionGUID: Mwmg/vQmRGWsDmSoRZuG2g== X-CSE-MsgGUID: GCx5odoySSqeDRcpARBtTg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,113,1770624000"; d="scan'208";a="258313001" Received: from dhhellew-desk2.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.245.244.171]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2026 02:14:57 -0700 Received: from kekkonen.localdomain (localhost [IPv6:::1]) by kekkonen.fi.intel.com (Postfix) with ESMTP id 013CF121D1C; Wed, 11 Mar 2026 11:16:51 +0200 (EET) Date: Wed, 11 Mar 2026 11:16:51 +0200 Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo From: Sakari Ailus To: "luo.liu.linux" Cc: mchehab@kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Re: [PATCH v2] media:v4l2-async:add debugfs under CONFIG_DEBUG_FS Message-ID: References: <20260121031456.1125096-1-luo.liu.linux@163.com> <24d41d72.7da6.19cdc1e683e.Coremail.luo.liu.linux@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <24d41d72.7da6.19cdc1e683e.Coremail.luo.liu.linux@163.com> On Wed, Mar 11, 2026 at 04:58:26PM +0800, luo.liu.linux wrote: > > Hi Sakari, > > Thank you very much for your reply and reminder. > > I think two latter #if's is useful，While modern compilers (such as GCC and Clang) possess "Dead Code Elimination" (DCE) capabilities and can optimize away function calls when CONFIG_DEBUG_FS is disabled, > > explicitly wrapping the relevant code blocks with #ifdef CONFIG_DEBUG_FS remains a standard and necessary practice in Linux kernel development. Just fix it, please? -- Sakari Ailus