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[147.75.199.223]) by mx.google.com with ESMTPS id s10-20020a05620a254a00b0077f061ee896si2074340qko.31.2023.12.21.02.43.17 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Dec 2023 02:43:17 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-8228-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel+bounces-8228-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) smtp.mailfrom="linux-kernel+bounces-8228-linux.lists.archive=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id AF2751C23B3E for ; Thu, 21 Dec 2023 10:43:17 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 479F574E32; Thu, 21 Dec 2023 10:41:01 +0000 (UTC) X-Original-To: linux-kernel@vger.kernel.org Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (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 120CB745D8 for ; Thu, 21 Dec 2023 10:40:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ellerman.id.au Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (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) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Swn5g3808z4xPh; Thu, 21 Dec 2023 21:40:55 +1100 (AEDT) From: Michael Ellerman To: Srikar Dronamraju Cc: linuxppc-dev , Christophe Leroy , Josh Poimboeuf , linux-kernel@vger.kernel.org, Mark Rutland , Nicholas Piggin , "Paul E. McKenney" , Peter Zijlstra , Rohan McLure , Valentin Schneider , Vincent Guittot , Aneesh In-Reply-To: <20231214180720.310852-1-srikar@linux.vnet.ibm.com> References: <20231214180720.310852-1-srikar@linux.vnet.ibm.com> Subject: Re: [PATCH v5 0/5] powerpc/smp: Topology and shared processor optimizations Message-Id: <170315510022.2192823.3630103323682637969.b4-ty@ellerman.id.au> Date: Thu, 21 Dec 2023 21:38:20 +1100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit On Thu, 14 Dec 2023 23:37:10 +0530, Srikar Dronamraju wrote: > PowerVM systems configured in shared processors mode have some unique > challenges. Some device-tree properties will be missing on a shared > processor. Hence some sched domains may not make sense for shared processor > systems. > > Most shared processor systems are over-provisioned. Underlying PowerVM > Hypervisor would schedule at a Big Core granularity. The most recent power > processors support two almost independent cores. In a lightly loaded > condition, it helps the overall system performance if we pack to lesser > number of Big Cores. > > [...] Applied to powerpc/next. [1/5] powerpc/smp: Enable Asym packing for cores on shared processor https://git.kernel.org/powerpc/c/aa80c6343fcf53cbc29f84ba9f89ca87d4e41350 [2/5] powerpc/smp: Disable MC domain for shared processor https://git.kernel.org/powerpc/c/0e1c1986e0e65746daa05405d7747ce882f83cf1 [3/5] powerpc/smp: Add __ro_after_init attribute https://git.kernel.org/powerpc/c/fd535a858ebeb1f478b1d065b6c057f52aad483a [4/5] powerpc/smp: Avoid asym packing within thread_group of a core https://git.kernel.org/powerpc/c/0e93f1c780e8fd315f1262467b7d35eb6f766d2f [5/5] powerpc/smp: Dynamically build Powerpc topology https://git.kernel.org/powerpc/c/c46975715f5a7b941aa09bc0539a8dbe297f308f cheers