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 71C581DDA2D for ; Tue, 29 Oct 2024 19:36:59 +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=1730230620; cv=none; b=crnFZAld/SyRuRaHj0i/7N19pab4phPuEF6PkDiQSaobv5NhGaJKeH+RCBiwCkS7CyIOXrJkuBnBiy6g9L8kH9pkMFJYx4Lbm35DpRdfneIKWHIiLnM5J0EXBuTDy+GN7tqhVQn23g2RwRJ2ik3pnaE0hFNgdkM5YBS1pEokwd0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730230620; c=relaxed/simple; bh=2G2w2Tlv1jSuI27J+1fmhh8XWzDm8+MT6bwJ2SuaDf0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Q7LHZ28lBgKLwivYnCs8nOf72v4YonCIXssCK0tAJOGwYPgEqheGcl8qiI60t1FbI7HAuoln2s0Fse2kr3FqK+JvRx5IpCk9lUAFCYdmKUQYyLNR2n+mAy8/jByKRyNrWd89EuB/B+Ohv7nzDJqiZrYZEvxQ0G88Ash0J0MKG3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K4CQ75R8; 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="K4CQ75R8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B718FC4CECD; Tue, 29 Oct 2024 19:36:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730230619; bh=2G2w2Tlv1jSuI27J+1fmhh8XWzDm8+MT6bwJ2SuaDf0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=K4CQ75R8RmQwLuo6ChAX0R4w5x6nmnAd0uKoGJ7ePHi/LwylX7IVJSDAI9YgWvyqx xYZz1pZhdYI6c/l91Ya6QQv6y/qP0UhzuQYVLkz7YtJ5hml6usxd2bUi58jopEjob5 13Nk6Bzt9FcsXaz3jOgTj85lzDqYtHrtpjPSF0m3wEMrWrduj/ej86wlxIjZSI9yYu 5kPL07s80XG9R5edM225KXEt/X48eYQNi0+bLAEvwXJrLHjI8pyoOyFg7naXN0yiUu dB/4QuyDqtmQ4ryiqZE7NYeX7JW6uGt+7b5zxs4lfOogW5fcZ6hbf/5EnMoBPXCk2Z tVIsTQIfAa7EQ== Date: Tue, 29 Oct 2024 09:36:58 -1000 From: Tejun Heo To: Andrea Righi Cc: David Vernet , linux-kernel@vger.kernel.org Subject: Re: [PATCH v5] sched_ext: Introduce NUMA awareness to the default idle selection policy Message-ID: References: <20241029101618.318812-1-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: <20241029101618.318812-1-arighi@nvidia.com> On Tue, Oct 29, 2024 at 11:16:18AM +0100, Andrea Righi wrote: > Similarly to commit dfa4ed29b18c ("sched_ext: Introduce LLC awareness to > the default idle selection policy"), extend the built-in idle CPU > selection policy to also prioritize CPUs within the same NUMA node. > > With this change applied, the built-in CPU idle selection policy follows > this logic: > - always prioritize CPUs from fully idle SMT cores, > - select the same CPU if possible, > - select a CPU within the same LLC domain, > - select a CPU within the same NUMA node. > > Both NUMA and LLC awareness features are enabled only when the system > has multiple NUMA nodes or multiple LLC domains. > > In the future, we may want to improve the NUMA node selection to account > the node distance from prev_cpu. Currently, the logic only tries to keep > tasks running on the same NUMA node. If all CPUs within a node are busy, > the next NUMA node is chosen randomly. > > Signed-off-by: Andrea Righi Applied to sched_ext/for-6.13. Thanks. -- tejun