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 BB7B9C00307 for ; Fri, 6 Sep 2019 03:39:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B6069206B8 for ; Fri, 6 Sep 2019 03:39:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Q21vkhzu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404450AbfIFDjG (ORCPT ); Thu, 5 Sep 2019 23:39:06 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:37560 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392155AbfIFDjF (ORCPT ); Thu, 5 Sep 2019 23:39:05 -0400 Received: by mail-pl1-f195.google.com with SMTP id b10so2436492plr.4; Thu, 05 Sep 2019 20:39:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=PXYF1M03RrcZFiPVCr+oafxI5KwHAQlJ1LzSSGxpPe0=; b=Q21vkhzuAlNVXS4iv5SGd/V6DPV1QKXyuezlpF/KupK8aco7bH8L6xFRe+3rzjhuIi LAAgTEASWHEHYVoAj7FVyFx3Xp5PZbquc6w1OkYAtwZ31L53Gw7JXTOe8GkX29sSmyjV NqjvYJ/6KjMr5tH9UVt7rQsEBIztiZMRWNJ+YYvVx2fp9XRuNC/ZzQX2uySLo8ZgybfR GJGLOSv0jY6mSzp91+tHXpjAgj9SSldX+EL6SzTMQdjoT8/KD5f31faQ7+RyIc/SPXp6 /32KsQdGPtu1HZwBEeCpce7NjL4p+ZDjPUPLNPaKFefZuIpcg1hxseD8csAyztj6AZPM R4+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=PXYF1M03RrcZFiPVCr+oafxI5KwHAQlJ1LzSSGxpPe0=; b=KFjEmvV0PE6sLGmE3TzJcVADHJWUxvkp24P6MFU0P2NNZrZWG60gXOUWHSDTdzT64L vpdJxNtxff9Gict5x/8JOyp7NXNVIC4WUSUbmHdS3UdXjRINJTbQ1R3AY/28PKN8cajo WnlP3LiA7JN03KpN1nPZDXqCgJ+EqJw3qO/z7Y4TjVG+25L3a6P4tJReGFYQQaxsnOZO j2rWD2MzOIoW9Q76kRkW4bwZBvjqsST1jxuKGiQA6AsLo5YGoCvwyxNN12NjKCG6Qwh1 LKRnAGzuF50BEuTMYX9LDEnYx1ifToPmv+GPFkASd3TDw3YpeUEG3jIJnAvrbv0JHL6/ L3mg== X-Gm-Message-State: APjAAAXVfXJZ0w63jQpfgWtINdcuhVkyXLBPUbceCD74/3oMcpy5zs8p LPn6hXdld2VkHTIZ8r51/7WHe5QR X-Google-Smtp-Source: APXvYqzgmhLuIsIaUW3PQSBJiLj2kLVGPu55mYjmZmnUcycRvpUbGvdC1nBjLxYMCIJYaHa9rSMSYA== X-Received: by 2002:a17:902:4381:: with SMTP id j1mr6842157pld.318.1567741145109; Thu, 05 Sep 2019 20:39:05 -0700 (PDT) Received: from localhost ([175.223.27.235]) by smtp.gmail.com with ESMTPSA id i6sm9072040pfq.20.2019.09.05.20.39.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Sep 2019 20:39:03 -0700 (PDT) Date: Fri, 6 Sep 2019 12:39:00 +0900 From: Sergey Senozhatsky To: Steven Rostedt Cc: Sergey Senozhatsky , Qian Cai , Petr Mladek , Sergey Senozhatsky , Michal Hocko , Eric Dumazet , davem@davemloft.net, netdev@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net/skbuff: silence warnings under memory pressure Message-ID: <20190906033900.GB1253@jagdpanzerIV> References: <20190904061501.GB3838@dhcp22.suse.cz> <20190904064144.GA5487@jagdpanzerIV> <20190904065455.GE3838@dhcp22.suse.cz> <20190904071911.GB11968@jagdpanzerIV> <20190904074312.GA25744@jagdpanzerIV> <1567599263.5576.72.camel@lca.pw> <20190904144850.GA8296@tigerII.localdomain> <1567629737.5576.87.camel@lca.pw> <20190905113208.GA521@jagdpanzerIV> <20190905132334.52b13d95@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190905132334.52b13d95@oasis.local.home> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (09/05/19 13:23), Steven Rostedt wrote: > > I think we can queue significantly much less irq_work-s from printk(). > > > > Petr, Steven, what do you think? [..] > I mean, really, do we need to keep calling wake up if it > probably never even executed? I guess ratelimiting you are talking about ("if it probably never even executed") would be to check if we have already called wake up on the log_wait ->head. For that we need to, at least, take log_wait spin_lock and check that ->head is still in TASK_INTERRUPTIBLE; which is (quite, but not exactly) close to what wake_up_interruptible() does - it doesn't wake up the same task twice, it bails out on `p->state & state' check. Or did I miss something? -ss