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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 258DBECE587 for ; Tue, 1 Oct 2019 20:53:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EBF6C215EA for ; Tue, 1 Oct 2019 20:53:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="meOs8PVk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726363AbfJAUxM (ORCPT ); Tue, 1 Oct 2019 16:53:12 -0400 Received: from mail-pf1-f180.google.com ([209.85.210.180]:34648 "EHLO mail-pf1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726166AbfJAUxM (ORCPT ); Tue, 1 Oct 2019 16:53:12 -0400 Received: by mail-pf1-f180.google.com with SMTP id b128so8967319pfa.1 for ; Tue, 01 Oct 2019 13:53:11 -0700 (PDT) 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=q5tkH36kuwwnrWU10TuXYBpNyDtmx/BnfoulQT3Lfc8=; b=meOs8PVkxH1PrVlZjI7E2hRMVWOq4GPJ7ro8cJgsIyGoWwG/GTZPZviTJ0JJBPkvL+ agBDA6WRuhMUpZ/v0fCBEtqMWWSmVFeVe+mCFBpBMeVFBASTRz9+7Rmx6kvFP1v6YkB1 RJQgCEs3Rs4ity1m/vJkHQxH1ExxLbEodtQjqwyy3o9DNqyiKEHTMB1wjNC0Hm/cqobO IzOeIbVjOooK9VpOVQ872hkwtZd5xFoWf39chaH86B5kMao5dA60kNPL2CqVoF91HUL1 lJRZIT7K//LoD40BTei5EFjztTNkD5FMNr8vtUUDWrvaqhEgYJizsfLqWs3E18WZdDBy AHhA== 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=q5tkH36kuwwnrWU10TuXYBpNyDtmx/BnfoulQT3Lfc8=; b=pZYH1nwDReqsV4F72h8L6+mkGNtheSagLlqg8bLJBj4Kdf1F2CVVjrvmwWJ4S8aKdu JX9u8WIj8KbTwa+J5S4hVsVAPyMm2hXI8bQKboya9bo4i6GHaejzNShYKzVmOIbeVPlM t3dLVQmyZUMxjUuQCDrKTBvfdGQ0NWvynMZwQ7FwpnVluXla7ePvUx6DzGLdwVnmLoYV S40m6iuiOiGWIsDt6s0RE3Kvma01ce4JDsxPl0h+wNfU//+dADzJC+1GdRrgXjTZK69C 5HJD/CF2L5HRO4cZu/SdgxazEKbPAt36ZOKlcltOBJigiDTTtDsBZYiklKkXmBCWQLRx CCXw== X-Gm-Message-State: APjAAAU9c9ECJqPrhyCKg4MouDPjbcwNjbVwbm8qvS9MkrVSfGl8e53Q xo/DSx9sfjRUTI/753cYWFQqIW0X X-Google-Smtp-Source: APXvYqxTpkbR6GjZZAPl9Or0SdmtuV0mDvfa1ZIDJhLdgVA4HoYsqgdwUPvPwb7fN+gePn3u37ZIrw== X-Received: by 2002:aa7:9081:: with SMTP id i1mr299872pfa.148.1569963191117; Tue, 01 Oct 2019 13:53:11 -0700 (PDT) Received: from ?IPv6:2620:15c:2c1:200:55c7:81e6:c7d8:94b? ([2620:15c:2c1:200:55c7:81e6:c7d8:94b]) by smtp.gmail.com with ESMTPSA id v3sm21834013pfn.18.2019.10.01.13.53.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Oct 2019 13:53:10 -0700 (PDT) Subject: Re: BUG: sk_backlog.len can overestimate To: John Ousterhout Cc: netdev@vger.kernel.org References: <01ac3ff4-4c06-7a6c-13fc-29ca9ed3ad88@gmail.com> <47fef079-635d-483e-b530-943b2a55fc22@gmail.com> From: Eric Dumazet Message-ID: Date: Tue, 1 Oct 2019 13:53:09 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 10/1/19 1:45 PM, John Ousterhout wrote: > > But this isn't really about socket resource limits (though that is > conflated in the implementation); it's about limiting the time spent > in a single call to __release_sock, no? The proxy used is memory usage, not time usage. cond_resched() or a preemptible kernel makes anything based on time flaky, you probably do not want to play with a time limit...