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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A3CDC3A5A9 for ; Tue, 5 May 2020 02:15:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6CE17206B9 for ; Tue, 5 May 2020 02:15:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="LKDcUD81" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726550AbgEECPW (ORCPT ); Mon, 4 May 2020 22:15:22 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:51553 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726531AbgEECPW (ORCPT ); Mon, 4 May 2020 22:15:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588644921; 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: in-reply-to:in-reply-to:references:references; bh=IZpts8zZ2x1XkemD/qL9WE6F/kUo3fXqTbXETpC992E=; b=LKDcUD81keIcYwcTDtWz/q2tn12Od63HNv2GmUG1MhWO6GnjQMpBEC3ovpiHhrugAae9/F 69Gooe7Vtw4Bpdm8+ySX1ulX1vpLyvjcZRLy0ZwT0ZMdCVmFdFSTEk1a6fLzjQYgVBsP5v qtDGLAgkwhUVg/T0kHtp3tL19HQvPfY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-324-aEKb66HkNFiW6VI3IyLpBA-1; Mon, 04 May 2020 22:15:19 -0400 X-MC-Unique: aEKb66HkNFiW6VI3IyLpBA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6A9F0460; Tue, 5 May 2020 02:15:18 +0000 (UTC) Received: from pick.fieldses.org (ovpn-118-132.rdu2.redhat.com [10.10.118.132]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 80F6E63F94; Tue, 5 May 2020 02:15:15 +0000 (UTC) Received: by pick.fieldses.org (Postfix, from userid 2815) id 6DB6F1202C0; Mon, 4 May 2020 22:15:14 -0400 (EDT) Date: Mon, 4 May 2020 22:15:14 -0400 From: "J. Bruce Fields" To: Tejun Heo Cc: Linus Torvalds , "open list:NFS, SUNRPC, AND..." , Jeff Layton , David Howells , Shaohua Li , Oleg Nesterov , Linux Kernel Mailing List Subject: Re: [PATCH 0/4] allow multiple kthreadd's Message-ID: <20200505021514.GA43625@pick.fieldses.org> References: <1588348912-24781-1-git-send-email-bfields@redhat.com> <20200501182154.GG5462@mtj.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200501182154.GG5462@mtj.thefacebook.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Fri, May 01, 2020 at 02:21:54PM -0400, Tejun Heo wrote: > Hello, > > On Fri, May 01, 2020 at 10:59:24AM -0700, Linus Torvalds wrote: > > Which kind of makes me want to point a finger at Tejun. But it's been > > mostly PeterZ touching this file lately.. > > Looks fine to me too. I don't quite understand the usecase tho. It looks > like all it's being used for is to tag some kthreads as belonging to the > same group. Can't that be done with kthread_data()? Yeah, so I'd forgotten about kthread->data. We're currently using it to pass the struct svc_rqst that a new nfsd thread needs. But once the new thread has gotten that, I guess it could set kthread->data to some global value that it uses to say "I'm a knfsd thread"? I suppose that would work. Though now I'm feeling greedy: it would be nice to have both some kind of global flag, *and* keep kthread->data pointing to svc_rqst (as that would give me a simpler and quicker way to figure out which client is conflicting). Could I take a flag bit in kthread->flags, maybe? --b.