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=-4.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 5A00DC433E9 for ; Tue, 12 Jan 2021 09:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 130EE23103 for ; Tue, 12 Jan 2021 09:55:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392878AbhALJyt (ORCPT ); Tue, 12 Jan 2021 04:54:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730628AbhALJys (ORCPT ); Tue, 12 Jan 2021 04:54:48 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB1ECC061786; Tue, 12 Jan 2021 01:54:07 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id y23so1487306wmi.1; Tue, 12 Jan 2021 01:54:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=4C7koV7P9bGKc+8BN3L92y65XqnLENV7qQnrXi9vunM=; b=IPMh9X5BrV1/JjonSuaCs7E9x+6WGO3aAUl8ReIGobx3T/2p8PMuEQyPwietoLfCcq L7LKDtMh2FziyR+3kuPAOJlo58Lne9hMVRZa64gMAgD5IevPqRxBw9QsNZbHHeIByGcc MD90h7SbWm+29I1ka3vigZpIz6a0OvFhK3C/byqpcjOk6pT8cxuO+aE4Ij4Ue3emWBWi dnABj7jE+tJSp7tOKpOhLauRhfhAxolnyWAvD5GEy6+QIKRvthXvpqGw9m4xuqjaQUon ts8uPeBCgr+zHVw3ROEiP1R1QNNnvLSo+Qa+pOneP3QGRmeAR69K2lPHs06CNRizr3L+ gfxQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=4C7koV7P9bGKc+8BN3L92y65XqnLENV7qQnrXi9vunM=; b=DRW5CEEHNbCNCWl0wkpQG0BnfHr0um9LWiOCOGhOorE7Td6HXhI+XLyTTBA2nRaNd1 HtIonQf56GZxwVKnq0LcX4vKkGyTs1WmpY8IaQ8yT54LgFcEecl8w1V8+haru/HyY7D+ CknAs1JIzm9Q0cbms2nZOwsImYd2mvTP35nErCgLN54KPDadal1xo9gvG/R8XRXFBeEZ Xxx7Kn5/OtJXt+WqpLg9vomPaJBrdPBluwHNzIOso2buTcxh8o8bGdrvmAlU4VM15FC0 yu2OtYavS90z+KzoGVY4AwyqwkqOvqURjHccZ3UhRZ/V75/R0s/k4jy7zFT1pZBYxv0V 953w== X-Gm-Message-State: AOAM530QdPTXeHHMmijI7ursggQNVYY3xeL8sfhcxUUbNqzuFaG+eZsv QsOgBnh1pq8+Q85HpKBuLks16tXeMiZHkA== X-Google-Smtp-Source: ABdhPJwF18MLwhoD3WVUiTBmIGtZqMEi6VY8eAKww2tvohbjOuX3m6HHG3M+2ZsIqRLEd+GpZGgtwA== X-Received: by 2002:a1c:e342:: with SMTP id a63mr2804716wmh.64.1610445246608; Tue, 12 Jan 2021 01:54:06 -0800 (PST) Received: from [192.168.1.122] (cpc159425-cmbg20-2-0-cust403.5-4.cable.virginm.net. [86.7.189.148]) by smtp.gmail.com with ESMTPSA id s13sm2876036wmj.28.2021.01.12.01.54.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 12 Jan 2021 01:54:05 -0800 (PST) Subject: Re: [PATCH net-next 0/5] skbuff: introduce skbuff_heads bulking and reusing To: Alexander Lobakin , "David S. Miller" , Jakub Kicinski Cc: Eric Dumazet , Edward Cree , Jonathan Lemon , Willem de Bruijn , Miaohe Lin , Steffen Klassert , Guillaume Nault , Yadu Kishore , Al Viro , netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210111182655.12159-1-alobakin@pm.me> From: Edward Cree Message-ID: Date: Tue, 12 Jan 2021 09:54:04 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20210111182655.12159-1-alobakin@pm.me> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Without wishing to weigh in on whether this caching is a good idea... Wouldn't it be simpler, rather than having two separate "alloc" and "flush" caches, to have a single larger cache, such that whenever it becomes full we bulk flush the top half, and when it's empty we bulk alloc the bottom half? That should mean fewer branches, fewer instructions etc. than having to decide which cache to act upon every time. -ed