Received: by 2002:a05:6358:3188:b0:123:57c1:9b43 with SMTP id q8csp37994128rwd; Wed, 12 Jul 2023 01:14:57 -0700 (PDT) X-Google-Smtp-Source: APBJJlG+kfAP3d8Y18QJeLmc87EO5RsqpusmdiXbT435PUwtqOPPSO7wJ88gX2vfapElokjhCymy X-Received: by 2002:a05:6a20:1018:b0:116:d935:f742 with SMTP id gs24-20020a056a20101800b00116d935f742mr17771624pzc.20.1689149697251; Wed, 12 Jul 2023 01:14:57 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1689149697; cv=none; d=google.com; s=arc-20160816; b=PlUY2IyKL8v56VXj2SUw4mvef0PTLWGclnHfGQkcopQ21P0vpeXjlCx+6EqwpTxYy+ Wmqw5atUiXoVa7FShaVhAXbqIxfYlsjNuevhrojsmM5SAaMNdDFhibu3HMq7biexqHNx 4p4eUDLhrRf8fNrVEoXWFPqdADANjOMir7XbudP46symx1YR+r580DwT/ZrQNEp1yR13 w01VMPVmDRiOA67dnzqUDs6dHIxHW+AJtGare6Vrssc1yNWLgVbmF0DWItRQ5XOhT1+N FVQ8xAHCBMgHTzb657KqgJ7lu+TYp2aB1rJzGF1SeZphPs1TTD/lILCKGftrLFNSX9Mf UfoA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=5TWVCjFGRExPcN05bVzne/2B6BKN45D6agRtviLb2cw=; fh=drqrF223StE7qFni7xVPqicTqHmEvKGsNqVbgCAaq5s=; b=rmotKw/DtX2sb16XMQNbISsQA0MaAKW3cl0aFhK9sbJSqqkvladwzq/nZvdn4iNRcy Mu1YlbRr7AqUrs1ahtD3W7Bs4nwNOdmMolUriQHFUQivRcU1KKw4pUDEWKtAmL3qXva1 yfNzlxgCKeMykis53Eo0qHtTpTI7zRQf+2s/pRdKEeV677kzlKS7ieadLg+IUYAo/XnL nAwdJcTeaSCpwHk4LL6rK9XbTPyM6OqFWV4C7DtVLglb3Gx9zjS0w4h2xOGqqpKx08zq U76UMQtWrqBl57KLEEJPhVpM8O/vwz07tTFbhDhz2TYY8wU8ySP3QQFB6NUVP32Z9yRr 8R8g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=ifUBNQvn; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id c11-20020a056a000acb00b006826f3512fbsi2898212pfl.253.2023.07.12.01.14.45; Wed, 12 Jul 2023 01:14:57 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=ifUBNQvn; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231906AbjGLIFV (ORCPT + 99 others); Wed, 12 Jul 2023 04:05:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229470AbjGLIFS (ORCPT ); Wed, 12 Jul 2023 04:05:18 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B04FE42; Wed, 12 Jul 2023 01:05:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=5TWVCjFGRExPcN05bVzne/2B6BKN45D6agRtviLb2cw=; b=ifUBNQvneXGD6J7waajKoLIn5D pG2U4BC29xw3bvWK+iSa+gOc5fps12nyXisO8GUjZ8wBkPcELGpNAi8PTuiQj86VL0sCdJPtz7/SJ xDuH43rN8cRQBY3ejlqYEvDoSWs/I9KWpHX7l4ReCDlLbCJaKIVUiQ9cJY3maD4eCUpWtv19dQc9v 4jLvvZZcrFyGbrozGDxTtRXwc6xqFTZdD2LdxXi8stUAEqMLCPZuf/VMl13F1s0oHfVPzh5xGfpnq 2A2xfm09toEHq4IIK/6YuxkSg15wVtz4ZkfBoKGkw+JRBLJPojBFi0ryZN9ICESH+dDlfa0WzYGH0 ztv3GCvQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1qJUqQ-00GTmW-3M; Wed, 12 Jul 2023 08:05:06 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id BABA33001E7; Wed, 12 Jul 2023 10:05:04 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id A1024243A2F82; Wed, 12 Jul 2023 10:05:04 +0200 (CEST) Date: Wed, 12 Jul 2023 10:05:04 +0200 From: Peter Zijlstra To: Tejun Heo Cc: Geert Uytterhoeven , Lai Jiangshan , "torvalds@linux-foundation.org" , Linux Kernel Mailing List , kernel-team@meta.com, Linux PM list , DRI Development , linux-rtc@vger.kernel.org, linux-riscv , netdev , Linux Fbdev development list , Linux MMC List , "open list:LIBATA SUBSYSTEM (Serial and Parallel ATA drivers)" , Linux-Renesas Subject: Re: Consider switching to WQ_UNBOUND messages (was: Re: [PATCH v2 6/7] workqueue: Report work funcs that trigger automatic CPU_INTENSIVE mechanism) Message-ID: <20230712080504.GA3100107@hirez.programming.kicks-ass.net> References: <20230511181931.869812-1-tj@kernel.org> <20230511181931.869812-7-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 11, 2023 at 11:39:17AM -1000, Tejun Heo wrote: > I wonder whether the right thing to do here is somehow scaling the threshold > according to the relative processing power. It's difficult to come up with a > threshold which works well across the latest & fastest and really tiny CPUs. > I'll think about it some more but if you have some ideas, please feel free > to suggest. We could scale by BogoMIPS I suppose, it's a bogus measurement, as per the name, but it does have some relation to how fast the machine is.