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 CEEA1C433EF for ; Wed, 20 Apr 2022 17:25:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381057AbiDTR1v (ORCPT ); Wed, 20 Apr 2022 13:27:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381010AbiDTR10 (ORCPT ); Wed, 20 Apr 2022 13:27:26 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F14374665E for ; Wed, 20 Apr 2022 10:24:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 96DC1B82115 for ; Wed, 20 Apr 2022 17:24:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 399F0C385A1; Wed, 20 Apr 2022 17:24:35 +0000 (UTC) Date: Wed, 20 Apr 2022 18:24:31 +0100 From: Catalin Marinas To: Marc Zyngier Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Will Deacon , Mark Rutland , James Morse , Suzuki K Poulose , Alexandru Elisei , Joey Gouly , kernel-team@android.com Subject: Re: [PATCH v2 00/10] arm64: Add initial support for FEAT_WFxT Message-ID: References: <20220419182755.601427-1-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220419182755.601427-1-maz@kernel.org> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Apr 19, 2022 at 07:27:45PM +0100, Marc Zyngier wrote: > A potential addition to this series would be to remove the event > generation from the counters, and rely on the timeout where it > matters (spinlocks?). Feedback welcome. I think we still need to keep the event generation around, at least for hardware bugs we don't know about. I don't think user-space rely on it though, people tend to come up with weird delays like isb ;). But yes, the WFET should be handy when it turns up in hardware. -- Catalin