Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754072Ab3HWJ0r (ORCPT ); Fri, 23 Aug 2013 05:26:47 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:60732 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753108Ab3HWJ0q (ORCPT ); Fri, 23 Aug 2013 05:26:46 -0400 Date: Fri, 23 Aug 2013 10:26:10 +0100 From: Catalin Marinas To: Sudeep KarkadaNagesha Cc: "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Lorenzo Pieralisi , Will Deacon , Thomas Gleixner , Daniel Lezcano Subject: Re: [PATCH v3 0/6] ARM/ARM64 architected timer updates Message-ID: <20130823092610.GB20186@darko.cambridge.arm.com> References: <1374492082-13686-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> <1376414984-14182-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> <5213A40C.6060509@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5213A40C.6060509@arm.com> Thread-Topic: [PATCH v3 0/6] ARM/ARM64 architected timer updates Accept-Language: en-GB, en-US Content-Language: en-US User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1640 Lines: 38 On Tue, Aug 20, 2013 at 06:14:52PM +0100, Sudeep KarkadaNagesha wrote: > On 13/08/13 18:29, Sudeep KarkadaNagesha wrote: > > From: Sudeep KarkadaNagesha > > > > This patch series adds support to configure the rate and enable the > > event stream for architected timer. The event streams can be used to > > impose a timeout on a WFE, to safeguard against any programming error > > in case an expected event is not generated or even to implement > > wfe-based timeouts for userspace locking implementations. > > > > Since the timer control register is reset to zero on warm boot, CPU > > PM notifier is added to re-initialize it. > > > > Changes v2->v3: > > 1. Moved ARM and ARM64 changes into separate patches > > 2. Added native hwcaps definations(ARM/ARM64) and compat-specific > > definitions(ARM64) to the users for the event stream feature. > > Can you review this version of the series ? I think the series is OK with the follow-up comments addressed. Could you please post a v4 to make sure I haven't missed anything? Another comment I have is whether we should make this feature configurable. The reason is mainly hardware validation: if some CPU implementation messes the event generation (and on ARMv8 it's a bit more complex as this is tied to the exclusive monitor) we risk not detecting it because of the event stream. Thanks. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/