From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id 572352C57; Tue, 23 Jan 2018 03:06:02 +0100 (CET) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Jan 2018 18:06:01 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,398,1511856000"; d="scan'208";a="21786208" Received: from debian-xvivbkq.sh.intel.com ([10.67.104.226]) by FMSMGA003.fm.intel.com with ESMTP; 22 Jan 2018 18:06:00 -0800 Date: Tue, 23 Jan 2018 10:05:36 +0800 From: Tiwei Bie To: Olivier Matz Cc: dev@dpdk.org, Yuanhan Liu , Maxime Coquelin , stable@dpdk.org Message-ID: <20180123020535.y2rhnz7qlnr4h7sg@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> <20180122025641.t4vgozvbjbms3edn@debian-xvivbkq.sh.intel.com> <20180122103858.n76gdigdmqeiwlik@platinum> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180122103858.n76gdigdmqeiwlik@platinum> User-Agent: NeoMutt/20170609 (1.8.3) Subject: Re: [dpdk-dev] [PATCH v2 1/4] net/virtio: fix queue flushing with vector Rx enabled X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Jan 2018 02:06:03 -0000 On Mon, Jan 22, 2018 at 11:38:58AM +0100, Olivier Matz wrote: > On Mon, Jan 22, 2018 at 10:56:41AM +0800, Tiwei Bie wrote: > > 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). > > Thank you for the review. What about something like this? > > struct rte_mbuf * > virtqueue_detach_unused(struct virtqueue *vq) > { > struct rte_mbuf *cookie; > struct virtio_hw *hw; > uint16_t start, end; > int type, idx; > > if (vq == NULL) > return NULL; > > hw = vq->hw; > type = virtio_get_queue_type(hw, vq->vq_queue_index); > start = vq->vq_avail_idx & (vq->vq_nentries - 1); > end = (vq->vq_avail_idx + vq->vq_free_cnt) & (vq->vq_nentries - 1); > end = (vq->vq_avail_idx + vq->vq_free_cnt) & (vq->vq_nentries - 1); > > for (idx = 0; idx < vq->vq_nentries; idx++) { > if (hw->use_simple_rx && type == VTNET_RQ) { > if (start <= end && idx >= start && idx < end) > continue; > if (start > end && (idx >= start || idx < end)) > continue; > cookie = vq->sw_ring[idx]; > if (cookie == NULL) > continue; > vq->sw_ring[idx] = NULL; > return cookie; > } else { > cookie = vq->vq_descx[idx].cookie; > if (cookie != NULL) { > vq->vq_descx[idx].cookie = NULL; > return cookie; > } > } > } > > return NULL; > } Apart from the repeated line, it looks good to me. Thanks! Thanks, Tiwei