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 2435ECA0ECA for ; Tue, 12 Sep 2023 08:08:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232452AbjILIIY (ORCPT ); Tue, 12 Sep 2023 04:08:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232531AbjILIIE (ORCPT ); Tue, 12 Sep 2023 04:08:04 -0400 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8741C1738; Tue, 12 Sep 2023 01:07:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1694506078; x=1726042078; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=4dV0kV+KXW7UJb+9tqUaPdb1gu1yn8BbHk8/t4Bxq1g=; b=XNWSAaWJ2RwihAcsy0YobrK6ODitNIqzKgtAQ11uX1FMUz/dlykasZpT DcJJyLQAduPeJ/V4sGZ+jk1RAm43P0kYe4OrwyynshWrRzMdiQ8rElFCL dC1jN9d11Hk7LD1hW50pgm29vmM8SxkahsyJrT5dwHsovie85wDAI+Z8H JArGmhFE3H/3zgQM2joXNVCzp7juUqFjXtDB3kmBYk+03jLv5xpmiOnwv l7Mqt72GVHMY88meIyXeWNSNpOk8EBv2Lv0GkmMnxN2W5MzCTwY66HS0+ cvSSeVyXcN4M3E5kgZvuUVTWLeU/ij1nXAGdfSAkasxzv8deHwnIoFAqn Q==; X-CSE-ConnectionGUID: 7hms3/EVQU6kwoNgywT1gw== X-CSE-MsgGUID: Wxbwhb0NT0acycYnDfqITw== X-ThreatScanner-Verdict: Negative X-IronPort-AV: E=Sophos;i="6.02,245,1688454000"; d="asc'?scan'208";a="4155476" X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa2.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 12 Sep 2023 01:07:57 -0700 Received: from chn-vm-ex04.mchp-main.com (10.10.85.152) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Tue, 12 Sep 2023 01:07:49 -0700 Received: from wendy (10.10.85.11) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21 via Frontend Transport; Tue, 12 Sep 2023 01:07:44 -0700 Date: Tue, 12 Sep 2023 09:07:28 +0100 From: Conor Dooley To: Guo Ren CC: Conor Dooley , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Guo Ren Subject: Re: [PATCH V11 00/17] riscv: Add Native/Paravirt qspinlock support Message-ID: <20230912-snitch-astronaut-41e1b694d24f@wendy> References: <20230910082911.3378782-1-guoren@kernel.org> <20230910-esteemed-exodus-706aaae940b1@spud> <20230910-baggage-accent-ec5331b58c8e@spud> <20230910-facsimile-answering-60d1452b8c10@spud> <20230911-nimbly-outcome-496efae7adc6@wendy> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="j7Df9CobqEwFv6J/" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org --j7Df9CobqEwFv6J/ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 12, 2023 at 09:33:57AM +0800, Guo Ren wrote: > On Mon, Sep 11, 2023 at 8:53=E2=80=AFPM Conor Dooley wrote: > > I added the new "riscv,isa-extensions" property in part to make > > communicating vendor extensions like this easier. Please try to use > > that. "qspinlock" is software configuration though, the vendor extension > > should focus on the guarantee of strong forward progress, since that is > > the non-standard aspect of your IP. >=20 > The qspinlock contains three paths: > - Native qspinlock, this is your strong forward progress. > - virt_spin_lock, for KVM guest when paravirt qspinlock disabled. > https://lore.kernel.org/linux-riscv/20230910082911.3378782-9-guoren@ke= rnel.org/ > - paravirt qspinlock, for KVM guest >=20 > So, we need a software configuration here, "riscv,isa-extensions" is > all about vendor extension. Ah right, yes it would only be able to be used to determine whether or not the platform is capable of supporting these spinlocks, not whether or not the kernel is a guest. I think I misinterpreted that snippet you posted, thinking you were trying to disable your new spinlock for KVM, sorry. On that note though, what about other sorts of guests? Will non-KVM guests not also want to use this virt spinlock? Thanks, Conor. --j7Df9CobqEwFv6J/ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZQAcMgAKCRB4tDGHoIJi 0qK3AQDulJZGiGgA+E47R8Ud6R5oEN/4EtWOAnkckiastVsR5QEA6lHxhL+c0RXG ffHqBpd4a2z2HVNcuw9EEcI8bR26oQE= =j90q -----END PGP SIGNATURE----- --j7Df9CobqEwFv6J/--