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 7B93C18C32A for ; Fri, 18 Oct 2024 20:26:40 +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=1729283200; cv=none; b=Tgwl7MiuMyrGD51BiQDu8KJ8DqWhTLO19m+9YUoEV+Hg+ZKJWlaKVkAEOdoI82qAk40o7fNmVRpDa1sul9B7U0jwnlnAmiSCiffFNkArR3nTq31/figrWFanqtKReeCprOaXgIIoEd8eTKrxQrfew1jz0PQef3Wozqozdia0HN8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729283200; c=relaxed/simple; bh=m1gA4gSTnAoCx9RzLHmgBYXWrCqqE/mPzaNWIWHHCrw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=U1WgIYFsHF/5OITyxvNrT136tZ1mxAsuuUer4AoUURKq9YeoZsFwO63inmQ8yztExIOn1tccTAOq9uqVdKev9uFjb8F0k/iP8cT2/NSHwkl8rIdgqCdxbfn3aftyzZDJht6xWXg7h3cvUpqHezuRIYdm9o0ke831ql8fdvPOLSA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LK4qxbrZ; 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="LK4qxbrZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1F2BC4CEC3; Fri, 18 Oct 2024 20:26:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729283200; bh=m1gA4gSTnAoCx9RzLHmgBYXWrCqqE/mPzaNWIWHHCrw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LK4qxbrZZns6+wBcKyk4G82DYGlDpQGTWxneGOrGc0jgZHWC2nRwa+UK4ZuLQrXgJ AODyigrXMmdwBqjmlZA1IFYvrSZBq6BpgI4DJMp3GGcrZRzq3c7aRT1DSffecrOgq1 AHffSYCfPDigWEJwIkxKOFs2EIJupMy6E6iagBwXQrDUWXXG1OLy4LZrg2AxVxky9/ q3FSdbYSkkYhNpwLbpsVW/o0aSP8SmZCacKlxDaBEzGqFrVJupwlCq+OlxJaG+uKFO K0F9v8axKJ5DK96WUHMdCaUo4TsAOvjcMOVE4ibVe+yiUbz7F5Xr4b+Hk9yN3RPIW1 ThSR2//Pul3xA== Date: Fri, 18 Oct 2024 10:26:38 -1000 From: Tejun Heo To: Andrea Righi Cc: David Vernet , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] sched_ext: improve WAKE_SYNC behavior for default idle CPU selection Message-ID: References: <20241018180951.599625-1-andrea.righi@linux.dev> 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: <20241018180951.599625-1-andrea.righi@linux.dev> On Fri, Oct 18, 2024 at 08:09:51PM +0200, Andrea Righi wrote: > In the sched_ext built-in idle CPU selection logic, when handling a > WF_SYNC wakeup, we always attempt to migrate the task to the waker's > CPU, as the waker is expected to yield the CPU after waking the task. > > However, it may be preferable to keep the task on its previous CPU if > the waker's CPU is cache-affine. > > The same approach is also used by the fair class and in other scx > schedulers, like scx_rusty and scx_bpfland. > > Therefore, apply the same logic to the built-in idle CPU selection > policy as well. > > Signed-off-by: Andrea Righi Applied to sched_ext/for-6.13. Thanks. -- tejun