Received: by 2002:a25:1506:0:0:0:0:0 with SMTP id 6csp3881438ybv; Mon, 10 Feb 2020 08:07:48 -0800 (PST) X-Google-Smtp-Source: APXvYqzeDWtGHpXKk9gfI9uLVSYo6+68Ob0CNlec1OEzYpcQqTlahXKZK5Z9ccFpPFmFUyBQzdO2 X-Received: by 2002:a9d:64b:: with SMTP id 69mr1528043otn.237.1581350868525; Mon, 10 Feb 2020 08:07:48 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1581350868; cv=none; d=google.com; s=arc-20160816; b=YOmvfDXBrXa9tu387SZ2eQHCb6VlXezoJEnImJV9X9jLMTN/deQjuJKVsiBCS/ekpX QV/3qMYdbNr1EZYGQygDycavmGsvHlowtNRW0Ck3cuN1sLg1OARLhr7ZHTkMyFSYW1iz BZ4xBRm7virfN9l+CqZMIEk66XLP7ScFhx5nYrDV6GiAYrtFaIUEZ+1uurPHeO7yB2+h T0A/6h7CNYjKEUUIGpv/n2WL5a/K5ShgRwPgeY/+6igUN0qWZGCn71fviIUhHSJfAxPx M7a5pY7NDk4ZgWtG3ziBldFNnopZ5lbBLEh8jhDSU7Qn7wFKKSjWvYVqo7VGWTAp0AQX zNgw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=dzqGRdPp+FEduZtNkMf2S/kJ+uAJgx7HsiKbyz4sYOw=; b=d14lIF7NdvCtyLjFS4g8FGeQoidCtiNuQ8CTW/YVVZ+BTPRht3XXi6355li9EZjTDU mCactdDV6HK/DSPZLOAj0ZVBKcqLz2quBm559SOA0eXo1n68oamEwdzoHpwtCK3Ymxvb PjZUL2ohieHeguI+peabwR3j5wRNjq2++/VS6ZkCSJSWWdwA8RLOnZcjxwmAwaSIsmjf clT8OeU2wBjkSTcqhFGkyoCJq/0A1d0csS4yfMm/nXwcEFFLPYMxRsJqFrfBw9Px/rjU 0yWPgVCLhy3/Wbx1nQ6ErKcy8+4TFJLocUfGUr/CENDeCSC9qUcesJEKa3BYploBQroM BjnQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id k8si384243otp.69.2020.02.10.08.07.36; Mon, 10 Feb 2020 08:07:48 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727727AbgBJQHF (ORCPT + 99 others); Mon, 10 Feb 2020 11:07:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:33104 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727120AbgBJQHF (ORCPT ); Mon, 10 Feb 2020 11:07:05 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 29C98ACD0; Mon, 10 Feb 2020 16:07:04 +0000 (UTC) Date: Mon, 10 Feb 2020 07:56:11 -0800 From: Davidlohr Bueso To: Andrew Morton Cc: linux-kernel@vger.kernel.org, mcgrof@kernel.org, broonie@kernel.org, alex.williamson@redhat.com Subject: Re: [PATCH -next 0/5] rbtree: optimize frequent tree walks Message-ID: <20200210155611.lfrddnolsyzktqne@linux-p48b> References: <20200207180305.11092-1-dave@stgolabs.net> <20200209174632.9c7b6ff20567853c05e5ee58@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20200209174632.9c7b6ff20567853c05e5ee58@linux-foundation.org> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 09 Feb 2020, Andrew Morton wrote: >Seems that all the caller sites you've converted use a fairly small >number of rbnodes, so the additional storage shouldn't be a big >problem. Are there any other sites you're eyeing? If so, do you expect >any of those will use a significant amount of memory for the nodes? I also thought about converting the deadline scheduler to use these, mainly benefiting pull_dl_task() but didn't get to it and I don't expect the extra footprint to be prohibitive. > >And... are these patches really worth merging? Complexity is added, >but what end-user benefit can we expect? Yes they are worth merging, imo (which of course is biased :) I don't think there is too much added complexity overall, particularly considering that the user conversions are rather trivial. And even for small trees (ie 100 nodes) we still benefit in a measurable way from these optimizations. Thanks, Davidlohr