From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 08010728E; Mon, 22 Jan 2018 03:57:07 +0100 (CET) X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Jan 2018 18:57:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,394,1511856000"; d="scan'208";a="195165093" Received: from debian-xvivbkq.sh.intel.com ([10.67.104.226]) by orsmga005.jf.intel.com with ESMTP; 21 Jan 2018 18:57:05 -0800 Date: Mon, 22 Jan 2018 10:56:41 +0800 From: Tiwei Bie To: Olivier Matz Cc: dev@dpdk.org, Yuanhan Liu , Maxime Coquelin , stable@dpdk.org Message-ID: <20180122025641.t4vgozvbjbms3edn@debian-xvivbkq.sh.intel.com> References: <20180118090733.12728-1-olivier.matz@6wind.com> <20180119155556.32597-1-olivier.matz@6wind.com> <20180119155556.32597-2-olivier.matz@6wind.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180119155556.32597-2-olivier.matz@6wind.com> User-Agent: NeoMutt/20170609 (1.8.3) Subject: Re: [dpdk-stable] [PATCH v2 1/4] net/virtio: fix queue flushing with vector Rx enabled X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Jan 2018 02:57:08 -0000 On Fri, Jan 19, 2018 at 04:55:53PM +0100, Olivier Matz wrote: > When using vector Rx mode (use_simple_rx = 1), vq->vq_descx[] is not > kept up to date. To properly detach the mbufs in this case, browse > sw_ring[] instead, as it's done in virtqueue_rxvq_flush(). > > Since we need virtio_get_queue_type(), also move this function in > virtqueue.h as a static inline. > > Fixes: fc3d66212fed ("virtio: add vector Rx") > Cc: stable@dpdk.org > > Signed-off-by: Olivier Matz > --- > > Tiwei, > > While it passes my test plan, please carefully check that what I did in > virtqueue_detatch_unused() is correct. I tried to reproduce what is done > in virtqueue_rxvq_flush(), but I may be mistaking due to the different > ring layout assumption and mbuf management between standard and vector. > > Thanks > Olivier > > > drivers/net/virtio/virtio_ethdev.c | 11 ----------- > drivers/net/virtio/virtqueue.c | 17 +++++++++++++++-- > drivers/net/virtio/virtqueue.h | 11 +++++++++++ > 3 files changed, 26 insertions(+), 13 deletions(-) > [...] > struct rte_mbuf * > virtqueue_detatch_unused(struct virtqueue *vq) > { > + struct virtio_hw *hw = vq->hw; > struct rte_mbuf *cookie; > int idx; > + int type = virtio_get_queue_type(hw, vq->vq_queue_index); > + > + if (vq == NULL) > + return NULL; > > - if (vq != NULL) > - for (idx = 0; idx < vq->vq_nentries; idx++) { > + for (idx = 0; idx < vq->vq_nentries; idx++) { > + if (hw->use_simple_rx && type == VTNET_RQ) { > + cookie = vq->sw_ring[idx]; > + if (cookie != NULL) { > + vq->sw_ring[idx] = NULL; Thanks for working on this! The vq->sw_ring[idx] isn't zeroed during Rx. So besides the check of (cookie != NULL), some other check is also needed to avoid freeing the mbufs already delivered to application. The mbufs in below interval belong to application: start: sw_ring[vq->vq_avail_idx & (vq->vq_nentries - 1)] (included) end: sw_ring[(vq->vq_avail_idx + vq->vq_free_cnt) & (vq->vq_nentries - 1)] (excluded) PS. (vq->vq_avail_idx & (vq->vq_nentries - 1)) can be greater than (vq->vq_avail_idx + vq->vq_free_cnt) & (vq->vq_nentries - 1). Thanks, Tiwei