From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0BEB21C36 for ; Fri, 8 Nov 2024 00:58:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731027539; cv=none; b=X1qhgqoTftEqr7IlwvjdR5o/Qv5sCJsfBDsqO3AY6a8xo6WEL0tFbMtnXYsazmRpiBMcn2NKXnclxxP+V3Wj2E4iGevEZy11trgkV4apxsPiVKl/BdU3Y3ucc2iaOj1KpDbXYEw+xrj5Q65EEAVYfo3n3REDahTG7ES66iK6PIM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731027539; c=relaxed/simple; bh=sAOPRgtSvUtPf0Vd9bBaKPLSEYUCIvcRu9bVqU1rQsg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=G2Rw7duycDnHThBu1CyTacURcJaxlhAObUWMg3znC2jGCZuKsC+1nrHtj2sKciF2x+e8mThRGXOUQXoBxzSJN9GymDB2MvUY3iZ0yu5bbEBUs1VWJOtOUj2l2VMum5ay+VGYmkEYV9KNtu/lLkp4kBTTT+WhD/GgopTvzQCQN1A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=evBSVb7T; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="evBSVb7T" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6BD5AC4CECC; Fri, 8 Nov 2024 00:58:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731027538; bh=sAOPRgtSvUtPf0Vd9bBaKPLSEYUCIvcRu9bVqU1rQsg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=evBSVb7T+hSXvZRjaFb8yIY8viNU2ngTAILeUVY4zSLm1nZ0FcFUTFkap9yeue2Qz agEgVIVmk5tVev2vkUXm0cVGfz5mk4senGJrumF4S2nj3Iow+8v3l0h+wl6ZTydbqR t2cX/9bD/amopMg461kmiRStJa7LwYl9MydKMa3jHfyCO3oRfWFlDJAmI+VxrL2XnQ LzfB9vl4S9uwPkfee2f+nAj7k4O3ll5l08spiyT92UWgT5HaveSu3ZNFpbcHEvHTsV Qc0o7CWtCwcbkXd9iKQlIpzV2fgFfL9SOdPMtP6pZ1e7mP9kYcSM9QaFtHEwiL/KH3 LnpM0DUGXZtgA== Date: Thu, 7 Nov 2024 14:58:57 -1000 From: Tejun Heo To: Andrea Righi Cc: David Vernet , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 sched_ext/for-6.13] sched_ext: Do not enable LLC/NUMA optimizations when domains overlap Message-ID: References: <20241108000136.184909-1-arighi@nvidia.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20241108000136.184909-1-arighi@nvidia.com> On Fri, Nov 08, 2024 at 01:01:36AM +0100, Andrea Righi wrote: > When the LLC and NUMA domains fully overlap, enabling both optimizations > in the built-in idle CPU selection policy is redundant, as it leads to > searching for an idle CPU within the same domain twice. > > Likewise, if all online CPUs are within a single LLC domain, LLC > optimization is unnecessary. > > Therefore, detect overlapping domains and enable topology optimizations > only when necessary. > > Moreover, rely on the online CPUs for this detection logic, instead of > using the possible CPUs. > > Fixes: 860a45219bce ("sched_ext: Introduce NUMA awareness to the default idle selection policy") > Signed-off-by: Andrea Righi Applied to sched_ext/for-6.13. Thanks. -- tejun