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 56F2DC77B7A for ; Fri, 2 Jun 2023 11:23:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235091AbjFBLX6 (ORCPT ); Fri, 2 Jun 2023 07:23:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234865AbjFBLX4 (ORCPT ); Fri, 2 Jun 2023 07:23:56 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E839919B; Fri, 2 Jun 2023 04:23:53 -0700 (PDT) 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=CW5FFS/sfC8BHeiLTKhUb9W7eHeglZWQrHMkx8btbA8=; b=OU/j2ooPhXxxOw3rjviWIUTvdj 8R1/ULne0Ku4w2Wh2VrqMchcHZpojiBD7WG442NEIG8mL4zgsiT9wHAH02BRt2xkCup9btESHDX0N rpG+5Tsn5vj/Q0dW2pxNRpA8h0rgUY62GCYoVK9np7sJb1TVoU1/Z44BdWKz6U5b/Pfbazw34m2Sh ifZ2pa98+9oF/LFtPv97wEV+nbTYgZfC6oKHCTCBQP2rboTBif8iV2GTIy9++j4fVOGXcACUEOaCx 3npYpmNO8rrfUdAMeEDdEp4Oj4ms2AJYcZofQTHWjiv285m1dLSpHJddkvCxCbfEQk3lUTqfkADy+ PEiCPeAw==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1q52sl-001JSl-2G; Fri, 02 Jun 2023 11:23:47 +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)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 4CC2930031F; Fri, 2 Jun 2023 13:23:47 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 348BB243B0938; Fri, 2 Jun 2023 13:23:47 +0200 (CEST) Date: Fri, 2 Jun 2023 13:23:47 +0200 From: Peter Zijlstra To: "Gautham R. Shenoy" Cc: K Prateek Nayak , linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, Tejun Heo , x86@kernel.org Subject: Re: [tip: sched/core] sched/fair: Multi-LLC select_idle_sibling() Message-ID: <20230602112347.GF620383@hirez.programming.kicks-ass.net> References: <168553468754.404.2298362895524875073.tip-bot2@tip-bot2> <3de5c24f-6437-f21b-ed61-76b86a199e8c@amd.com> <20230601111326.GV4253@hirez.programming.kicks-ass.net> <20230601115643.GX4253@hirez.programming.kicks-ass.net> <20230601120001.GJ38236@hirez.programming.kicks-ass.net> <20230601145113.GA559993@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 02, 2023 at 02:36:37PM +0530, Gautham R. Shenoy wrote: > Yes, this is what the topology looks like > > |---------------------------------------------------------------------------------| > | | > | ----------- ----------- ----------- ----------- ----------- ----------- | > | |(0-7) | |(8-15) | |(16-23) | |(48-55) | |(56-63) | |(64-71) | | > | | LLC0 | | LLC1 | | LLC2 | | LLC6 | | LLC7 | | LLC8 | | > | |(96-103) | |(104-111)| |(112-119)| |(144-151)| |(152-159)| |(160-167)| | > | ----------- ----------- ----------- ----------- ----------- ----------- | > | | > | | > | ----------- ----------- ----------- ----------- ----------- ----------- | > | |(24-31) | |(32-39) | |(40-47) | |(72-79) | |(80-87) | |(88-95) | | > | | LLC3 | | LLC4 | | LLC5 | | LLC9 | | LLC10 | | LLC11 | | > | |(120-127)| |(128-135)| |(136-143)| |(168-175)| |(176-183)| |(184-191)| | > | ----------- ----------- ----------- ----------- ----------- ----------- | > | | > |---------------------------------------------------------------------------------| Yup, that's the pictures I found online. > > I would think it is the latter since NPS4 does that but let me go verify. > > 2 groups of 6 each is the vertical split which is NPS2. > > 4 groups of 3 each is the vertical and horizontal split, which is > NPS4. > > In both these cases, currently the domain hierarchy > > SMT --> MC --> NODE --> NUMA > > where the NODE will be the parent of MC and be the 2nd level wakeup domain. > > If we define CLS to be the group with 3 LLCs, which becomes the parent > of the MC domain, then, the hierarchy would be > > NPS1 : SMT --> MC --> CLS --> DIE > NPS2 : SMT --> MC --> CLS --> NODE --> NUMA > NPS4 : SMT --> MC --> CLS --> NUMA > > NPS2 will have 5 domains within a single socket. Oh well! I think cluster/CLS is taken for L2, we should not re-purpose that for groups of L3. Anyway, yes, 5 levels. Shouldn't be a problem though, right?