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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF5F2C77B6E for ; Thu, 13 Apr 2023 18:37:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229753AbjDMShH (ORCPT ); Thu, 13 Apr 2023 14:37:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229546AbjDMShF (ORCPT ); Thu, 13 Apr 2023 14:37:05 -0400 Received: from mail-ej1-x62b.google.com (mail-ej1-x62b.google.com [IPv6:2a00:1450:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D17A97AB0; Thu, 13 Apr 2023 11:37:02 -0700 (PDT) Received: by mail-ej1-x62b.google.com with SMTP id ud9so39543837ejc.7; Thu, 13 Apr 2023 11:37:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1681411021; x=1684003021; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=Ctjyu73iM54aIyhlbCG/deKG/CTsP8kAywi8XWV3uyI=; b=OA4zI3Uq/q5iAEVUQDYMIt2ftZ72Y3PEesQ3ZnQbkiO1nXrM2v/+xv14KbO86QfJF2 KStCCliQ4dXztgQa1hVtVmqCS+2s0X/8kN7OfqiTph9SynNXPanELDUmg2eZEoX5MbCO zI8W4RMkc8NZMhzmvVSy6EF43NI0yXTn9LQWUcIcLi+Y9ZuDbMCiCShWhBiFEyFZlPx+ IllgFY2zc3TM8h00+q/QRA3v81ANYuwdi+jJg69HsgnoJiKYN2jq7T8qMi3u2oqmKEyO ka3wfkSrvzwh35aUsCAMmytOqqx9HI/DOXDpO1EUcNCEn2vAHZsNRTxGyi+doJ2h6RI7 BYTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681411021; x=1684003021; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=Ctjyu73iM54aIyhlbCG/deKG/CTsP8kAywi8XWV3uyI=; b=d7e4Duvy/73gObUvm3hp6Hu4AxVmIqeBOh0CJkB2ZkdTzNBWEewVUStJso2xfTKjd9 uIOPlBu2PVqtLnmnEySj5jiPWdXkA+rFzogYeZDf6/xAcsfwuoJ2RykdHAe+mIkBSHCI HQeXcnGHpmM/xedHfVjGIRzO7EqdEoxL6+DNtgkFWxYJ0IafEa3WMBGW2n7jwhLUI8jx 4avMVLq4Gj61tv8rSc3MFJrlfC43pgykvEGTKxOUHCBBK9EBlihSTFPQzdR/reg9rS1l 20lQp0q7gRQD7t2z0Kv2nG8e0Hi3gkfvE4WM1CE5pxaB8//sPdfdcoVxB6U4ltWO0Ec+ OboA== X-Gm-Message-State: AAQBX9f0/F4gfDkp1UkYhxdz2Iu0QtlVpEr+CiSdKT+jSKMAGRRIqdcZ kVW0eXtRMdQRVLYl7Zwwqnk0fmDfsg== X-Google-Smtp-Source: AKy350bW9uOb3WYUA3v/brxo+veLe07VYr/JDy+8LcWabxZ1ztGNMbox44ItKnSuTbK7wm7zGKYm6Q== X-Received: by 2002:a17:907:20b2:b0:94e:6b12:caab with SMTP id pw18-20020a17090720b200b0094e6b12caabmr3593954ejb.51.1681411021214; Thu, 13 Apr 2023 11:37:01 -0700 (PDT) Received: from p183 ([46.53.248.76]) by smtp.gmail.com with ESMTPSA id mh21-20020a170906eb9500b0094e4d197160sm1281817ejb.202.2023.04.13.11.37.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Apr 2023 11:37:00 -0700 (PDT) Date: Thu, 13 Apr 2023 21:36:58 +0300 From: Alexey Dobriyan To: Andrew Morton Cc: Chunguang Wu , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH] fs/proc: add Kthread flag to /proc/$pid/status Message-ID: <59774223-680e-4b64-87ea-ab7e524be369@p183> References: <20230412141216.c8f2c1313f34ee0100ac9ae4@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230412141216.c8f2c1313f34ee0100ac9ae4@linux-foundation.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 12, 2023 at 02:12:16PM -0700, Andrew Morton wrote: > On Wed, 12 Apr 2023 22:34:02 +0800 Chunguang Wu wrote: > > > user can know that a process is kernel thread or not. > > > > ... > > > > --- a/fs/proc/array.c > > +++ b/fs/proc/array.c > > @@ -434,6 +434,12 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, > > > > task_state(m, ns, pid, task); > > > > + if ((mm == NULL) || (task->flags & PF_KTHREAD)) { > > + seq_puts(m, "Kthread:\tYes\n"); > > + } else { > > + seq_puts(m, "Kthread:\tNo\n"); > > + } "mm" check is redundant. PF_KTHREAD should be enough. If you're doing this, just print 0/1. > > if (mm) { > > task_mem(m, mm); > > task_core_dumping(m, task); > > Well.. Why is this information useful? I want to add: for a shell script. Real programs can read /proc/*/stat . > What is the use case? > > There are many ways of working this out from the existing output - why > is this change required?