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=-6.5 required=3.0 tests=BAYES_00,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 A6A1EC4338F for ; Tue, 10 Aug 2021 03:27:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D65560FD8 for ; Tue, 10 Aug 2021 03:27:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236687AbhHJD2N (ORCPT ); Mon, 9 Aug 2021 23:28:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:43707 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236662AbhHJD2M (ORCPT ); Mon, 9 Aug 2021 23:28:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628566070; 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=yOmYoCRgGWoxX4Ig7wMcZct6gYjWHtKD2JHpEcgfojM=; b=ACjnbefypvlXbxtEAXivssUngv1pzAMvdibfQvYlP1/MR+8IMOp/0OPtt03tOSxptuYwGG t6JThX/mypYWNe8fU9qra+0kons0XDm6zJSppGfmO62ikide5NnYIUVyFiZ+wnJHu5qfVm xSD715DmqXk3iaBcly1aSNGBCgykX98= 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-369-iTpxUWxQPN6WB6ifkHsvSw-1; Mon, 09 Aug 2021 23:27:07 -0400 X-MC-Unique: iTpxUWxQPN6WB6ifkHsvSw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B85251008060; Tue, 10 Aug 2021 03:27:05 +0000 (UTC) Received: from T590 (ovpn-13-190.pek2.redhat.com [10.72.13.190]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 45D385C23A; Tue, 10 Aug 2021 03:26:58 +0000 (UTC) Date: Tue, 10 Aug 2021 11:26:54 +0800 From: Ming Lei To: Christoph Hellwig Cc: Jens Axboe , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Dan Schatzberg Subject: Re: [PATCH V4 0/7] loop: cleanup charging io to mem/blkcg Message-ID: References: <20210806080302.298297-1-ming.lei@redhat.com> <20210809064159.GA19070@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210809064159.GA19070@lst.de> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Chritoph, On Mon, Aug 09, 2021 at 08:41:59AM +0200, Christoph Hellwig wrote: > FYI, I am still of the firm opinion that the current cgroup support in > the loop driver needs to be reverted and be redone cleanly from scratch > without impacting the normal non-cgroup path at all. This patchset basically re-writes the original patches much or less, and the normal non-cgroup path is basically not changed compared with before 87579e9b7d8d ("loop: use worker per cgroup instead of kworker"). Original way is to use kthread_work, now it is switched to queue_work() for unifying the code, but all commands are just added to one list and run batching in the single worker context, which is very similar with kthread_worker. Can you share us what your expectations are in the re-write? Such as: 1) no impact on normal non-cgroup path 2) ... 3) ... Thanks, Ming