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 74C0E10A3E for ; Sun, 10 Nov 2024 19:38:08 +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=1731267488; cv=none; b=PZI5ZK80uZiO7P7M6U3YcDgOAxrSwzkyqQSFRUz6WDz8R3s4jlzVuFYRTg+4uvbZzcBZ83F/wgipVj3q5XY5YbUcNltPLjqK6tmUthGs2obhFBDfI9jHorwd0ZlRNJs3+4xtHalqR2J0ad1K5Z17K4ROhoTPiurDB8/yfnP4JZQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731267488; c=relaxed/simple; bh=5raMsL3YtEnQyRroqq9Rox8lVOkFKhPtiGZ9lTnhkgU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dhGB09mJVfLwtyA77bheoOxK57Pa4wzRhqRmrbtwpmzbqf4vaqayWzA1l9QSPsF/hCGmTe4lsmBD7K8Pk7Z4YUUKe3Jz7tkIcgvEcHwrcpkt8JnjKQ7syIiktAdNfI/DWhi8tG0ypebmP1VV0Kc5aH/i1ViK9wbmyGVhF9G3jNk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m118utQW; 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="m118utQW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6867C4CECD; Sun, 10 Nov 2024 19:38:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731267488; bh=5raMsL3YtEnQyRroqq9Rox8lVOkFKhPtiGZ9lTnhkgU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=m118utQWIGUa4e4DgltV1NqVZp2+Q6Fikl0FKEUXB8GeKszg0Tb/0UDACgTlGIxTh K3FI79SCjafrgPOrUjaL/sHdLIS8vzYd6AGt27DBZiuD+Tzm/8Cc05HBqBpK4dupwP UJo+sVzxgxlIKg3fu6bUYPtKwnxV9WfLXAZII8bdxkvZ6+JLt/tyu/TOzpc4r4MzAZ keZ7hLXYzZsYYplDqcSmTIF2+sJ7Zh+xm0MjbS3TStl/QqXqjVUnNqgI0AUKEHoLgs ZuDI+tC/zBX53HKS6Vx/HSrJbdpwJSlqAy2mk83QgQYfu9I2iFaRdz2MCQVE0G/fOn tfPRtHE1Nw4iA== Date: Sun, 10 Nov 2024 09:38:06 -1000 From: Tejun Heo To: Johannes Bechberger Cc: Andrea Righi , Changwoo Min , void@manifault.com, linux-kernel@vger.kernel.org, kernel-team@meta.com, sched-ext@meta.com, ggherdovich@suse.com, dschatzberg@meta.com, yougmark94@gmail.com, changwoo@igalia.com, kernel-dev@igalia.com Subject: Re: [PATCH 2/3] sched_ext: Rename scx_bpf_consume() to scx_bpf_dsq_move_to_local() Message-ID: References: <20241109194853.580310-1-tj@kernel.org> <20241109194853.580310-3-tj@kernel.org> <81281555-d57f-4507-a3a5-ea9d1aa27871@gmail.com> <42a6a270d7b01c02eb4d78bb408165641c6b435a@mostlynerdless.de> 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: <42a6a270d7b01c02eb4d78bb408165641c6b435a@mostlynerdless.de> Hello, On Sun, Nov 10, 2024 at 04:09:15PM +0000, Johannes Bechberger wrote: > Hello all, > > the changes look really good and the renaming will make it much easier > to explain what a simple scheduler does, lowering the entry barrier. Andrea, Changwoo, Johannes, can you guys reply with Acked-by so that I can record the consensus in the commit? > > > * Insert @p into the vtime priority queue of the DSQ identified by @dsq_id. > > > - * Tasks queued into the priority queue are ordered by @vtime and always > > > - * consumed after the tasks in the FIFO queue. All other aspects are identical > > > - * to scx_bpf_dsq_insert(). > > > + * Tasks queued into the priority queue are ordered by @vtime. All other aspects > > > + * are identical to scx_bpf_dsq_insert(). > > > > > > I suggest keeping this part, "and always consumed after the tasks > > > in the FIFO queue." Otherwise, IIRC, there is no place to explain > > > the priority between FIFO and priority DSQs explicitly. > > > > > I think we don't allow anymore to use the FIFO queue and the prio queue > > at the same time. Maybe we should clarify this here and also mention > > that we can't use scx_bpf_dsq_insert_vtime() with the built-in DSQs. > > I would like to second that we clarify the differences between the built-in > and the non-builtin DSQs. Will add that. > Also: Could we mention that the priority queue is stable? If I remember correctly, > then tasks with the same priority are scheduled in a FIFO manner. If it is, that's accidental. I don't think we want to make a guarantee about ordering stability. It's not like that's going to make any meaningful difference. Thanks. -- tejun