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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 916F5CFB43F for ; Mon, 7 Oct 2024 13:27:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=SXbRJe48FbLdryBiDuyzz5qjG7SGMp/3ojw4H0GYm9Y=; b=SRmVmJsbolqTuA3pWtMMSUUKjp 0ElZ1l9FlerS/IEfW9KU6xATVZ7uDMPB4lhV/Wr39um363yORj3VklrH4amEfaKAsNv5xEnkbck32 EXCxT3rt0pqZ5VX2EEtTLBvh1iQCsyp7VP+4qn6yCNF0mXGtJ8JMq4wxm9dizqYpNuvTftthL4FPo WcOxGa9Jfr2V99z/ZJ2AnBfhYWxkNaQwWxID9KCyTqC4SlbJ4LuWuB/YvBdB3tpYwDwXM0j3U6efj npW65ofKPqJpRli8SEc9sKIbt/AZb10bBCEG/lNw1UuRj9+igkoTph9iYhsFmZws22Ne3+ys4UNDa bJoFoAjA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sxnlZ-00000002ViL-242m; Mon, 07 Oct 2024 13:27:13 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sxnVh-00000002SEJ-0y2N for linux-arm-kernel@lists.infradead.org; Mon, 07 Oct 2024 13:10:51 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0E512DA7; Mon, 7 Oct 2024 06:11:18 -0700 (PDT) Received: from pluto (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6496A3F640; Mon, 7 Oct 2024 06:10:47 -0700 (PDT) Date: Mon, 7 Oct 2024 14:10:45 +0100 From: Cristian Marussi To: Sudeep Holla Cc: Justin Chen , arm-scmi@vger.kernel.org, cristian.marussi@arm.com, linux-arm-kernel@lists.infradead.org, peng.fan@nxp.com, bcm-kernel-feedback-list@broadcom.com, florian.fainelli@broadcom.com Subject: Re: [PATCH] firmware: arm_scmi: Queue in scmi layer for mailbox implementation Message-ID: References: <20241004221257.2888603-1-justin.chen@broadcom.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241007_061049_365006_2AD6FD51 X-CRM114-Status: GOOD ( 14.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Oct 07, 2024 at 02:04:10PM +0100, Sudeep Holla wrote: > On Fri, Oct 04, 2024 at 03:12:57PM -0700, Justin Chen wrote: > > The mailbox layer has its own queue. However this confuses the per > > message timeouts since the clock starts ticking the moment the messages > > get queued up. So all messages in the queue have there timeout clocks > > ticking instead of only the message inflight. To fix this, lets move the > > queue back into the SCMI layer. > > > > I think this has come up in the past. We have avoided adding addition > locking here as the mailbox layer takes care of it. Has anything changed > recently ? I asked for an explanation in my reply (we crossed each other mails probably) since it alredy came up in the past a few times and central locking seemed not to be needed...here the difference is about the reason...Justin talks about message timeouts related to the queueing process..so I asked to better explain the detail (and the anbomaly observed) since it still does not seem to me that even in this case the lock is needed....anyway I can definitely be woring of course :D Thanks, Cristian