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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 A12FCC432BE for ; Sat, 28 Aug 2021 14:07:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76C0960E8B for ; Sat, 28 Aug 2021 14:07:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234307AbhH1OI1 (ORCPT ); Sat, 28 Aug 2021 10:08:27 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:43396 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230163AbhH1OI0 (ORCPT ); Sat, 28 Aug 2021 10:08:26 -0400 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1630159655; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=It4Lds59IjUbHF19nJTRlAWmtvD1xmA9F7P5RHXxWlI=; b=HGwbiGMRcZNAzkvRkLtgrTdn52xAH1NQI2g3+fRV9g2eKf8pG3B3efhWFjpuM8EvmUZrE/ 1HiXmI5jtDmi3hGgmSxs3rMs8r87dT8j26hC9h4skX56yZD4IJ5bNm/F5cqJcyHhxFfqca T8rMkKgCQDuBMcM7aZG/hL4xgF39FW1yXT4uYS5eoiczEzY4Q02GYdGlvdFJ10QwFMFq+f eJ3cwxszfL9vcQUfwbHf3cXLNSSAzN8rEHO3n9VaJfKym9L47WJAO+AxES77wvhinaRfkN 5YgmChrFoFTRLRXeWYo9pkalB+aCAPxfjeBMywJnxjkPf1Yt4rQWE3QQwzbOqQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1630159655; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=It4Lds59IjUbHF19nJTRlAWmtvD1xmA9F7P5RHXxWlI=; b=QpT2F+LG4109YgJvvGCDquOSmu7mgSLePGIE/3mao0StIrldmKBfmNQF9JwHgFOHW+CaiJ xSEi613rOQ8DQ8DA== To: =?utf-8?B?546L5pOO?= Cc: Peter Zijlstra , Ingo Molnar , Frederic Weisbecker , Michal Hocko , Davidlohr Bueso , Will Deacon , "Paul E. McKenney" , Dirk Behme , linux-kernel@vger.kernel.org Subject: Re:Re: [PATCH,RESEND] softirq: Introduce SOFTIRQ_FORCED_THREADING In-Reply-To: References: Date: Sat, 28 Aug 2021 16:07:34 +0200 Message-ID: <87wno5hdcp.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Qing, On Sat, Aug 28 2021 at 10:18, =E7=8E=8B=E6=93=8E wrote: >> On Mon, Aug 23 2021 at 11:33, Wang Qing wrote: >> What you are proposing here is completly different as you enforce >> softirq execution in context of ksoftirqd only. > > Thank you for reply and explanation, I just provide a choice to balance > the execution of softirq according to their own business scenarios. That's not a choice. Forced interrupt threading is a boot-time option and not a compile time boolean. So with your change you even changed the behaviour of the kernel when your magic config switch is not selected by the user. >> What are you referring to? PREEMPT_RT does not modify the priority of >> ksoftirqd. If system designers want to do that, then they can do so from >> user space.=20 > > I refer to the kernel-3.14 RT Patches. I used it at that time and achieve= d=20 > very good results. There is a reason why RT does not use this anymore and switched to a different model. As I said before. Just because it works for you, it's not necessarily a solution which should be exposed for general consumption. > I remember where I saw that softirqd was split into the original process= =20 > and the RT process. This can partially solve my problem. Your patch has absolutely nothing to do with that. You just picked some random part out of those 7+ years old patches and then claim that it's something RT does, which is just not true. Thanks, tglx