Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA7A1C433FE for ; Wed, 15 Dec 2021 03:46:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239630AbhLODqi (ORCPT ); Tue, 14 Dec 2021 22:46:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235616AbhLODqh (ORCPT ); Tue, 14 Dec 2021 22:46:37 -0500 Received: from mail-vk1-xa35.google.com (mail-vk1-xa35.google.com [IPv6:2607:f8b0:4864:20::a35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A663C061574 for ; Tue, 14 Dec 2021 19:46:37 -0800 (PST) Received: by mail-vk1-xa35.google.com with SMTP id m19so13790866vko.12 for ; Tue, 14 Dec 2021 19:46:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=posk.io; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6TekgYXvLI9+PhAB10t1a5FqyPcohZFo1S/h5MUzllc=; b=BFsYMu+UZJj1SArv/r1ASXkdEhkDV6ze8dTrFKXh3BqRPxE59I75lLftewi2N6Gdp/ hVHKuBSEEOKvlfo92eHsingxtFZVif9P2kEl6cecf9Wk9hgAZt3SwH61VWQ5b7m3J709 IoSEdRybiuRcZB9Tc8r+YKx7thHVGC2NJjigGfuhZ8jYYnD9Hpweg6EIeb/5PtEUWuvu kyEP1L9s9nZcncRMdGj7SPlQOUtLRYUv61wDX+vOEyJAa1M6B4sbg9XU/AZqbfSyq23I d6/QxcitDHYWCTs0pWw+Zuc6i5WaCwCgQSyJJ8IwrdQmpo/1vzgd4eMJBefEbUP2/lW2 GgNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6TekgYXvLI9+PhAB10t1a5FqyPcohZFo1S/h5MUzllc=; b=HxLKor7iSNBsED6ptCGaFtScKRUw9y9+BfnCbiDEoUjutsPtp5nBUF8iWWMYE8TOQj hakRaocumG1hr8qGlD1fC7uWR94KdXEflR4YQ1PVSLdBfxnCWJ80PHRV0EeUByzLutfB M+vudW5s0rU5WV/ISgUBIdRgNjgz68NpQJ/OLvE8Sj4P6xvh0sDivLn6dTuM3pFdGGBK bWN3SA3dN/FAbpsE72yBrmxgGnlvSLvXSKJCtN9gjLaBLdEZkPCQ5vg8MaPr01byhTku W2PGfcfefuUaf0Co6eB0lq1mX3H2pMpqYwnZ61fwMWZNEmw1ttEm0tNQLIWPQ61/mmll 9YfQ== X-Gm-Message-State: AOAM532Yvkv8M+ryzHQ35SUt2RyCIEtujJKnWPcuUVIddHIvzJ7j8mkN 7yXHirSTyaEU7kYz3VmgumI3+2V1E6fJ/d/mu/CPZw== X-Google-Smtp-Source: ABdhPJwT1P/z+guQQbhBVQaBckIuopJw6LK6HpQeJEPxLY8JvjeQl8Z+vJL49XKvD80YtUUcd36/oxeIFPPgqM4AECg= X-Received: by 2002:a05:6122:221c:: with SMTP id bb28mr2417373vkb.27.1639539996199; Tue, 14 Dec 2021 19:46:36 -0800 (PST) MIME-Version: 1.0 References: <20211214204445.665580974@infradead.org> In-Reply-To: <20211214204445.665580974@infradead.org> From: Peter Oskolkov Date: Tue, 14 Dec 2021 19:46:25 -0800 Message-ID: Subject: Re: [RFC][PATCH 0/3] sched: User Managed Concurrency Groups To: Peter Zijlstra Cc: Ingo Molnar , Thomas Gleixner , juri.lelli@redhat.com, Vincent Guittot , dietmar.eggemann@arm.com, Steven Rostedt , Ben Segall , mgorman@suse.de, bristot@redhat.com, Linux Kernel Mailing List , Linux Memory Management List , linux-api@vger.kernel.org, x86@kernel.org, Paul Turner , Peter Oskolkov , Andrei Vagin , Jann Horn , Thierry Delisle Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 14, 2021 at 12:55 PM Peter Zijlstra wrote: > > Hi, > > This is actually tested code; but still missing the SMP wake-to-idle machinery. > I still need to think about that. Thanks, Peter! At a first glance, your main patch does not look much smaller than mine, and I thought the whole point of re-doing it was to throw away extra features and make things smaller/simpler... Anyway, I'll test your patchset over the next week or so and let you know if anything really needed is missing (other than waking an idle server if there is one on a worker wakeup; this piece is definitely needed). > > I'll post my test-hack as a reply, but basically it does co-operative and > preemptive UP-like user scheduling. > > Patches go on top of tip/master as they rely on the .fixup removal > recently merged in tip/x86/core. > > Also, I still need to audit a bunch of mm code, because I'm not sure things are > actually as well behaved as this code supposes they are. >