From mboxrd@z Thu Jan 1 00:00:00 1970 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 01B51CCA47B for ; Tue, 12 Jul 2022 00:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231607AbiGLAqb (ORCPT ); Mon, 11 Jul 2022 20:46:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230501AbiGLAq3 (ORCPT ); Mon, 11 Jul 2022 20:46:29 -0400 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F6E626552 for ; Mon, 11 Jul 2022 17:46:28 -0700 (PDT) Received: by mail-pg1-x52c.google.com with SMTP id f11so5310561pgj.7 for ; Mon, 11 Jul 2022 17:46:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:subject:to:cc:references:in-reply-to:mime-version :message-id:content-transfer-encoding; bh=MrBfNE+lDrxaFJmsqP9cx+ZcpAfc2gGGi9kDbUQJuak=; b=AgrBuA/N7SPeE0ze9eLiHhmshi8vqlRkj6fI2MAJDwco8R8Tvrg6CDeXNUfe/8Baw4 FarK65V59sOTTqzNrJOSrUU0RZ4FY08LQ0d5cKMSFPC/84q8HywdMytK/LVqp7tXb2O9 9I3oHj2WJQsRZCxdo3+hXo0xkxm8D5GgcFb4mh+gIpVXYezDEF21wxEqlYogJ1FmKhWC beU+RNCStS8JyRun+VfxbJCQQqZi3juCOwd9ksruWpx7kTirKBb07/O8qX2hmGpGUEol mFijh2GiX5mcMOwTrFejgTbN+9ILgW4I4c8ghHR9lMTG+Trv0Caes+KLPTewt72igFc8 0IJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:subject:to:cc:references:in-reply-to :mime-version:message-id:content-transfer-encoding; bh=MrBfNE+lDrxaFJmsqP9cx+ZcpAfc2gGGi9kDbUQJuak=; b=r/IKsD+/dfowxqg9cg6IVV5ue0xLnFkjXVr0Ya8doHubcOHqm60Gj/SBh328xSPZXj XgD249uVFtYAHSS7yDWco/IqT+Zi/6HCeeIz8zUoBUhfKYhP3mHiMLvdfZ/Y0LjFgzlL 6Lo0QQivdBQttHqx4EqctqO11JKf46ZwmiL1/8AQKWuEenjBWloShn0EQZj5oYVqmFOW Nuci8J+NXIq/jEspz2DSeC9T++fxkiS6ehrlUmFmOMflhJ5EJhYQHhlgCVZ8qBhj7/1P zfrIKpXWkGhXK1YkJMb1YJIaBVDsDeKXjsgHoYWKasfUwee1qUzerW7xZNCGy1/IDb4c oycw== X-Gm-Message-State: AJIora9wtKCGxgs+9afxNeRf3X+0ZeZCCgrVuta1RsO36j9JUBCMoa2t xHXlMvdNp5JvZRIwayHMmd4= X-Google-Smtp-Source: AGRyM1u1a9zdg2qkjZET4V7deeC+2n7ftFUv8TmGkg0fEk/WCC0IChTXrOM6WwDrob4HObq4C0zaJA== X-Received: by 2002:a63:9041:0:b0:415:c0e8:c588 with SMTP id a62-20020a639041000000b00415c0e8c588mr15801558pge.282.1657586788141; Mon, 11 Jul 2022 17:46:28 -0700 (PDT) Received: from localhost (193-116-203-247.tpgi.com.au. [193.116.203.247]) by smtp.gmail.com with ESMTPSA id c4-20020a056a00008400b0051bc36b7995sm5349494pfj.62.2022.07.11.17.46.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Jul 2022 17:46:27 -0700 (PDT) Date: Tue, 12 Jul 2022 10:46:22 +1000 From: Nicholas Piggin Subject: Re: [PATCH 06/13] locking/qspinlock: merge qspinlock_paravirt.h into qspinlock.c To: Peter Zijlstra Cc: Boqun Feng , linux-kernel@vger.kernel.org, Waiman Long , Ingo Molnar , Will Deacon References: <20220704143820.3071004-1-npiggin@gmail.com> <20220704143820.3071004-7-npiggin@gmail.com> In-Reply-To: MIME-Version: 1.0 Message-Id: <1657586071.6w3o6t2gfx.astroid@bobo.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Excerpts from Peter Zijlstra's message of July 6, 2022 3:36 am: > On Tue, Jul 05, 2022 at 07:20:37PM +0200, Peter Zijlstra wrote: >> On Tue, Jul 05, 2022 at 12:38:13AM +1000, Nicholas Piggin wrote: >> > There isn't much reason to keep these separate. >>=20 >> The reason was so that other paravirt implementations could be added. >>=20 >> The CNA thing was also implemented this way... >=20 > Also, (TIL) s390 seems to have a copy of all this: >=20 > b96f7d881ad9 ("s390/spinlock: introduce spinlock wait queueing") Right. powerpc is going to add another one. I've also been struggling to make PV qspinlock work well for us and the PV hooks didn't quite help. This series is just me dumping what I had done while working with the code until now, feel free to take or leave it. The PV things could easily be moved out again or conditionally compiled when another implementation in tree comes up. > it might be nice if it were possible to fold that back into this with a > different paravirt implementation; but I've not looked at it in any > great detail yet. I would like to fold powerpc some time (or at least merge it with s390 which it is possibly more similar with) but at the moment kind of need prove it even works on our systems and solves issues before bothering other archs with it. It's not all that complicated though so not too concerned about carrying it in arch. https://lists.ozlabs.org/pipermail/linuxppc-dev/2022-July/245977.html Thanks, Nick