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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38469CA9EC3 for ; Thu, 31 Oct 2019 08:49:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 090B620873 for ; Thu, 31 Oct 2019 08:49:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727054AbfJaItt (ORCPT ); Thu, 31 Oct 2019 04:49:49 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:33418 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726874AbfJaIts (ORCPT ); Thu, 31 Oct 2019 04:49:48 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 9CED2566D52269F09AA3; Thu, 31 Oct 2019 16:49:45 +0800 (CST) Received: from [127.0.0.1] (10.173.222.27) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.439.0; Thu, 31 Oct 2019 16:49:34 +0800 Subject: Re: [PATCH v2 03/36] irqchip/gic-v3-its: Allow LPI invalidation via the DirectLPI interface To: Marc Zyngier , , CC: Eric Auger , James Morse , Julien Thierry , Suzuki K Poulose , Thomas Gleixner , Jason Cooper , Lorenzo Pieralisi , "Andrew Murray" , Jayachandran C , "Robert Richter" References: <20191027144234.8395-1-maz@kernel.org> <20191027144234.8395-4-maz@kernel.org> From: Zenghui Yu Message-ID: Date: Thu, 31 Oct 2019 16:49:32 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <20191027144234.8395-4-maz@kernel.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.222.27] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, On 2019/10/27 22:42, Marc Zyngier wrote: > We currently don't make much use of the DirectLPI feature, and it would > be beneficial to do this more, if only because it becomes a mandatory > feature for GICv4.1. > > Signed-off-by: Marc Zyngier I have no objection to this patch, which says: Reviewed-by: Zenghui Yu But this patch really drives me to look through all callsites of dev_event_to_col(), the abstraction which can be used _only_ with physical LPI mappings. I find that when building the INV command, we use dev_event_to_col() to find the "sync_obj" and then pass it to the following SYNC command. But the "INV+SYNC" will be performed both on physical LPI and *VLPI* (lpi_update_config/its_send_inv). So I have two questions about the way we sending INV on VLPI: 1) Which "sync" command should be followed? SYNC or VSYNC? (we currently use SYNC, while the spec says, SYNC "ensures all outstanding ITS operations associated with *physical* interrupts for the Redistributor are globally observed ...") 2) The "sync_obj" we are currently using seems to be wrong. Thanks, Zenghui