Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:56442 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750766AbeDXPRc (ORCPT ); Tue, 24 Apr 2018 11:17:32 -0400 From: Kalle Valo To: Daniel Mack Cc: Loic Poulain , linux-wireless@vger.kernel.org, wcn36xx@lists.infradead.org, Ramon Fried , Bjorn Andersson Subject: Re: [PATCH 1/1 RFC] wcn36xx: fix buffer commit logic on TX path References: <20180410174245.1116-1-daniel@zonque.org> <20180410174245.1116-2-daniel@zonque.org> Date: Tue, 24 Apr 2018 18:17:26 +0300 In-Reply-To: (Daniel Mack's message of "Tue, 24 Apr 2018 16:33:19 +0200") Message-ID: <87604gbpmh.fsf@kamboji.qca.qualcomm.com> (sfid-20180424_171736_504202_15052E21) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Daniel Mack writes: > Hi Loic, > > On Wednesday, April 11, 2018 03:30 PM, Loic Poulain wrote: >>> /* Move the head of the ring to the next empty descriptor */ >>> - ch->head_blk_ctl = ctl->next; >>> + ch->head_blk_ctl = ctl_skb->next; >>> + >>> + /* Commit all previous writes and set descriptors to VALID */ >>> + wmb(); >> >> Is this first memory barrier really needed? from what I understand, we >> only need to ensure that the control descriptor is marked valid at the >> end of the procedure and we don't really care about the paylod one. >> >>> + desc_skb->ctrl = ch->ctrl_skb; >>> + wmb(); >>> + desc_bd->ctrl = ch->ctrl_bd; >>> >>> /* >>> * When connected and trying to send data frame chip can be in sleep >> >> Otherwise, patch makes sense. > > This patch has somehow vanished from patchwork. It's still in patchwork, just in state RFC: https://patchwork.kernel.org/patch/10333553/ -- Kalle Valo