From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D1F377262F; Mon, 1 Sep 2025 08:53:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756716810; cv=none; b=R2HCFnXNS6zOx17K43ITBMRRsgwNlCgjaYd+dKyHR9dNbvNTJYfKnhZQ3t4FYDpiwVGtDJIEIIP9ns+P9znFbVZswms1VN3KFWj4dAH0ROUQd23De7I0CkHdGoOwB/pLs1QbL+vX21HkNkUT0cv5dsO4tVRAJTZC8g/ZcRv/HrQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756716810; c=relaxed/simple; bh=Nu0Z5YRABht37ceEFhru9sO3g0wQQK80E5FaZzZqeME=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PhrXeDzSHcH3BW+CN2KhWiYQQe2NQ1aRwsaQphB4g4DBSPyPnrBvoMLEHNTJ1Tjtu1lM3Z7da3bfa5hcuwglKkezWr4I/OJ7RAxezn4rG4ugpYL4KJbUUbzDZBYMSOkQ0ou5eH8XZbzGt8Oc2NP8Q3rU2yQyh8fek26cmJeKodA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=RA4zwAAE; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="RA4zwAAE" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; 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=StnaVQ/kuJKs04O83dX5k4oJKlm7slZS7P8l56c6/pw=; b=RA4zwAAEQiCqRY/TooPy/tk0ud rw/w/lrPMKIuCcLgBggd3vuF4fpgSHX2M6sOVAuXSsUxc6uo62EztDxZp6mUyLYACfh9aAiQ4hUoK 82CRdGtK06o3JG8leT4mdeqFWpOvxCq7zbalqum94HHR3wsQiUtwGOvNJ/2o6yTp+OPGxXR5MGYPV 1yOapB3oD+7v/gfi+iv8++UHuT1iMd7Mz0pOnUMIQprUWkrJXSVst3cjO2AyrjWrnKgBhq12Fknwk r0JV17FlQBdTf/VOYEqYBwF38xuhW7tHMPCWst5TfMJAk8UyIIHkIoyKzZPme1MsIqukkAMY1KpFN VoQ5ou9w==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1ut0HF-00000003gW1-0qU0; Mon, 01 Sep 2025 08:52:37 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 3F3FB300342; Mon, 01 Sep 2025 10:52:36 +0200 (CEST) Date: Mon, 1 Sep 2025 10:52:36 +0200 From: Peter Zijlstra To: Shrikanth Hegde Cc: Christophe Leroy , K Prateek Nayak , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Juri Lelli , Vincent Guittot , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , thomas.weissschuh@linutronix.de, Li Chen , Bibo Mao , Mete Durlu , Tobias Huschle , Easwar Hariharan , Guo Weikang , "Rafael J. Wysocki" , Brian Gerst , Patryk Wlazlyn , Swapnil Sapkal , "Yury Norov [NVIDIA]" , Sudeep Holla , Jonathan Cameron , Andrea Righi , Yicong Yang , Ricardo Neri , Tim Chen , Vinicius Costa Gomes Subject: Re: [PATCH v7 4/8] powerpc/smp: Introduce CONFIG_SCHED_MC to guard MC scheduling bits Message-ID: <20250901085236.GK4068168@noisy.programming.kicks-ass.net> References: <20250826041319.1284-1-kprateek.nayak@amd.com> <20250826041319.1284-5-kprateek.nayak@amd.com> <609a980b-cbe3-442b-a492-91722870b156@csgroup.eu> <20250826080706.GC3245006@noisy.programming.kicks-ass.net> <20250826094358.GG3245006@noisy.programming.kicks-ass.net> <7137972e-bc7a-432c-94be-755ba9029d8c@linux.ibm.com> <20250901083507.GD4067720@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250901083507.GD4067720@noisy.programming.kicks-ass.net> On Mon, Sep 01, 2025 at 10:35:07AM +0200, Peter Zijlstra wrote: > On Thu, Aug 28, 2025 at 08:13:51PM +0530, Shrikanth Hegde wrote: > > > > --- a/arch/powerpc/Kconfig > > > +++ b/arch/powerpc/Kconfig > > > @@ -170,6 +170,9 @@ config PPC > > > select ARCH_STACKWALK > > > select ARCH_SUPPORTS_ATOMIC_RMW > > > select ARCH_SUPPORTS_DEBUG_PAGEALLOC if PPC_BOOK3S || PPC_8xx > > > + select ARCH_SUPPORTS_SCHED_SMT if PPC64 && SMP > > > + select ARCH_SUPPORTS_SCHED_MC if PPC64 && SMP > > > + select SCHED_MC if ARCH_SUPPORTS_SCHED_MC > > > > Wondering if this SCHED_MC is necessary here? shouldn't it be set by arch/Kconfig? > > Ah, so without this SCHED_MC becomes a user selectable option, with this > it is an always on option (for ppc64) -- no user prompt. > > That is, this is the only way I found to have similar semantics to this: > > > > -config SCHED_MC > > > - def_bool y > > > - depends on PPC64 && SMP > > > - > > Which is also not a user selectable option. > > > nit: Also, can we have so they are still sorted? > > select ARCH_SUPPORTS_SCHED_MC if PPC64 && SMP > > select ARCH_SUPPORTS_SCHED_SMT if PPC64 && SMP > > Sure, let me flip them. I need to prod that that patch anyway, built > robot still ain'ted happy. Looks like 44x/iss476-smp_defconfig (iow 32bit power) also wants SCHED_MC, so it should be: config SCHED_MC def_bool y depends on SMP Its just SMT that's a PPC64 special.