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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A243CC19F2B for ; Thu, 4 Aug 2022 09:52:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238815AbiHDJwL (ORCPT ); Thu, 4 Aug 2022 05:52:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239413AbiHDJvz (ORCPT ); Thu, 4 Aug 2022 05:51:55 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C17A161D45 for ; Thu, 4 Aug 2022 02:51:54 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 5DFC120E1A; Thu, 4 Aug 2022 09:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1659606713; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/nsJKgzrKUYTFEYR/s+B+vppfN7Ux9/9bNVvETvtuWg=; b=hyI0F/n5p9Bi3RL3QWCDGmshv/0uLUhUnZ7cvEM+R7dSv/6pMYOKN1iFqKx6gq3S1uy2tg DPDdx+MBHc8OId6wZ6XD497c2r96fyISJjmNok+CbjPrWy9tdqYcjsdcwGZMo2cj/ppEbD kRVLKxpGsTh0SZjJYNLcn54zvaKVbAo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1659606713; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/nsJKgzrKUYTFEYR/s+B+vppfN7Ux9/9bNVvETvtuWg=; b=fRNXxYYns8TENO7k4Br5NTPs1e6oOrTKAGnOSf/6zHi5xmPJ0bO8QMSzhwm0cnxw+5HsYa VjJK2o8NBWkISIDQ== Received: from suse.de (unknown [10.163.43.106]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 2551A2C146; Thu, 4 Aug 2022 09:51:47 +0000 (UTC) Date: Thu, 4 Aug 2022 10:51:50 +0100 From: Mel Gorman To: Ingo Molnar Cc: Libo Chen , K Prateek Nayak , peterz@infradead.org, vincent.guittot@linaro.org, tim.c.chen@linux.intel.com, 21cnbao@gmail.com, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org, tglx@linutronix.de Subject: Re: [PATCH] sched/fair: no sync wakeup from interrupt context Message-ID: <20220804095150.GG3493@suse.de> References: <20220711224704.1672831-1-libo.chen@oracle.com> <82620137-5aa5-6cf1-f7aa-6a298e2f7856@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 04, 2022 at 10:55:12AM +0200, Ingo Molnar wrote: > > * Libo Chen wrote: > > > Oh yes, I have no issue with holding the patch back until the regression > > is fully understood. I was just a little confused on your reference to > > Mel's comments. [...] > > Yeah, that was just me getting confused about which change Mel was > referring to, as I was looking for external confirmation saying what I was > thinking about the patch: in_task()/in_interrupt() heuristics rarely do > well. ;-) > Even though I was referring to something else, the reported regression is still a regression. Prateek's report and what I brought up in https://lore.kernel.org/all/20220715100738.GD3493@suse.de/ are both simply examples where changes to affine wakeup can have surprising results. -- Mel Gorman SUSE Labs