From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by dpdk.org (Postfix) with ESMTP id C7B5DDE3 for ; Sun, 22 Jan 2017 04:47:20 +0100 (CET) Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga105.fm.intel.com with ESMTP; 21 Jan 2017 19:47:19 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,267,1477983600"; d="scan'208";a="51209869" Received: from fmsmsx107.amr.corp.intel.com ([10.18.124.205]) by orsmga004.jf.intel.com with ESMTP; 21 Jan 2017 19:47:19 -0800 Received: from fmsmsx113.amr.corp.intel.com (10.18.116.7) by fmsmsx107.amr.corp.intel.com (10.18.124.205) with Microsoft SMTP Server (TLS) id 14.3.248.2; Sat, 21 Jan 2017 19:47:18 -0800 Received: from shsmsx152.ccr.corp.intel.com (10.239.6.52) by FMSMSX113.amr.corp.intel.com (10.18.116.7) with Microsoft SMTP Server (TLS) id 14.3.248.2; Sat, 21 Jan 2017 19:47:18 -0800 Received: from shsmsx102.ccr.corp.intel.com ([169.254.2.88]) by SHSMSX152.ccr.corp.intel.com ([169.254.6.132]) with mapi id 14.03.0248.002; Sun, 22 Jan 2017 11:47:16 +0800 From: "Lu, Wenzhuo" To: Billy McFall , "thomas.monjalon@6wind.com" CC: "dev@dpdk.org" Thread-Topic: [PATCH v3 2/3] net/e1000: e1000 igb support to free consumed buffers Thread-Index: AQHSczaBpBs0713TmEOqgKSsuKWfyqFD3LIg Date: Sun, 22 Jan 2017 03:47:16 +0000 Message-ID: <6A0DE07E22DDAD4C9103DF62FEBC09093B55CADD@shsmsx102.ccr.corp.intel.com> References: <20170120160109.1088-1-bmcfall@redhat.com> <20170120160109.1088-3-bmcfall@redhat.com> In-Reply-To: <20170120160109.1088-3-bmcfall@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3 2/3] net/e1000: e1000 igb support to free consumed buffers 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: Sun, 22 Jan 2017 03:47:21 -0000 Hi Billy, > -----Original Message----- > From: Billy McFall [mailto:bmcfall@redhat.com] > Sent: Saturday, January 21, 2017 12:01 AM > To: thomas.monjalon@6wind.com; Lu, Wenzhuo > Cc: dev@dpdk.org; Billy McFall > Subject: [PATCH v3 2/3] net/e1000: e1000 igb support to free consumed > buffers >=20 > Add support to the e1000 igb driver for the new API to force free consume= d > buffers on Tx ring. e1000 igb driver does not implement a tx_rs_thresh to= free > mbufs, it frees a slot in the ring as needed, so a new function needed to= be > written. >=20 > Signed-off-by: Billy McFall > --- > drivers/net/e1000/e1000_ethdev.h | 2 + > drivers/net/e1000/igb_ethdev.c | 1 + > drivers/net/e1000/igb_rxtx.c | 126 > +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 129 insertions(+) >=20 > diff --git a/drivers/net/e1000/e1000_ethdev.h > b/drivers/net/e1000/e1000_ethdev.h > index 81a6dbb..39b2f43 100644 > --- a/drivers/net/e1000/e1000_ethdev.h > +++ b/drivers/net/e1000/e1000_ethdev.h > @@ -315,6 +315,8 @@ int eth_igb_tx_queue_setup(struct rte_eth_dev *dev, > uint16_t tx_queue_id, > uint16_t nb_tx_desc, unsigned int socket_id, > const struct rte_eth_txconf *tx_conf); >=20 > +int eth_igb_tx_done_cleanup(void *txq, uint32_t free_cnt); > + > int eth_igb_rx_init(struct rte_eth_dev *dev); >=20 > void eth_igb_tx_init(struct rte_eth_dev *dev); diff --git > a/drivers/net/e1000/igb_ethdev.c b/drivers/net/e1000/igb_ethdev.c index > 8843dd1..12a1a30 100644 > --- a/drivers/net/e1000/igb_ethdev.c > +++ b/drivers/net/e1000/igb_ethdev.c > @@ -408,6 +408,7 @@ static const struct eth_dev_ops eth_igb_ops =3D { > .rx_descriptor_done =3D eth_igb_rx_descriptor_done, > .tx_queue_setup =3D eth_igb_tx_queue_setup, > .tx_queue_release =3D eth_igb_tx_queue_release, > + .tx_done_cleanup =3D eth_igb_tx_done_cleanup, > .dev_led_on =3D eth_igb_led_on, > .dev_led_off =3D eth_igb_led_off, > .flow_ctrl_get =3D eth_igb_flow_ctrl_get, > diff --git a/drivers/net/e1000/igb_rxtx.c b/drivers/net/e1000/igb_rxtx.c = index > 45f3f24..00cd2aa 100644 > --- a/drivers/net/e1000/igb_rxtx.c > +++ b/drivers/net/e1000/igb_rxtx.c > @@ -1277,6 +1277,132 @@ eth_igb_tx_queue_release(void *txq) > igb_tx_queue_release(txq); > } >=20 > +static int > +igb_tx_done_cleanup(struct igb_tx_queue *txq, uint32_t free_cnt) { > + struct igb_tx_entry *sw_ring; > + volatile union e1000_adv_tx_desc *txr; > + uint16_t tx_first; /* First segment analyzed. */ > + uint16_t tx_id; /* Current segment being processed. */ > + uint16_t tx_last; /* Last segment in the current packet. */ > + uint16_t tx_next; /* First segment of the next packet. */ > + int count; > + > + if (txq !=3D NULL) { > + count =3D 0; > + sw_ring =3D txq->sw_ring; > + txr =3D txq->tx_ring; > + > + /* > + * tx_tail is the last sent packet on the sw_ring. Goto the end > + * of that packet (the last segment in the packet chain) and > + * then the next segment will be the start of the oldest > segment > + * in the sw_ring. This is the first packet that will be > + * attempted to be freed. > + */ > + > + /* Get last segment in most recently added packet. */ > + tx_first =3D sw_ring[txq->tx_tail].last_id; > + > + /* Get the next segment, which is the oldest segment in ring. > */ > + tx_first =3D sw_ring[tx_first].next_id; > + > + /* Set the current index to the first. */ > + tx_id =3D tx_first; > + > + /* > + * Loop through each packet. For each packet, verify that an > + * mbuf exists and that the last segment is free. If so, free > + * it and move on. > + */ > + while (1) { > + tx_last =3D sw_ring[tx_id].last_id; > + > + if (sw_ring[tx_last].mbuf) { > + if (txr[tx_last].wb.status & > + E1000_TXD_STAT_DD) { > + /* > + * Increment the number of packets > + * freed. > + */ > + count++; > + > + /* Get the start of the next packet. */ > + tx_next =3D sw_ring[tx_last].next_id; > + > + /* > + * Loop through all segments in a > + * packet. > + */ > + do { > + > rte_pktmbuf_free_seg(sw_ring[tx_id].mbuf); > + sw_ring[tx_id].mbuf =3D NULL; > + sw_ring[tx_id].last_id =3D tx_id; > + > + /* Move to next segemnt. */ > + tx_id =3D sw_ring[tx_id].next_id; > + > + } while (tx_id !=3D tx_next); > + > + if (unlikely(count =3D=3D (int)free_cnt)) > + break; > + } else > + /* > + * mbuf still in use, nothing left to > + * free. > + */ > + break; > + } else { > + /* > + * There are multiple reasons to be here: > + * 1) All the packets on the ring have been > + * freed - tx_id is equal to tx_first > + * and some packets have been freed. > + * - Done, exit > + * 2) Interfaces has not sent a rings worth of > + * packets yet, so the segment after tail is > + * still empty. Or a previous call to this > + * function freed some of the segments but > + * not all so there is a hole in the list. > + * Hopefully this is a rare case. > + * - Walk the list and find the next mbuf. If > + * there isn't one, then done. > + */ > + if (likely((tx_id =3D=3D tx_first) && (count !=3D 0))) > + break; > + > + /* > + * Walk the list and find the next mbuf, if any. > + */ > + do { > + /* Move to next segemnt. */ > + tx_id =3D sw_ring[tx_id].next_id; > + > + if (sw_ring[tx_id].mbuf) > + break; > + > + } while (tx_id !=3D tx_first); > + > + /* > + * Determine why previous loop bailed. If > there > + * is not an mbuf, done. > + */ > + if (sw_ring[tx_id].mbuf =3D=3D NULL) > + break; > + } > + } > + } else > + count =3D -ENODEV; > + > + return count; > +} > + > +int > +eth_igb_tx_done_cleanup(void *txq, uint32_t free_cnt) { > + return igb_tx_done_cleanup(txq, free_cnt); } > + > static void > igb_reset_tx_queue_stat(struct igb_tx_queue *txq) { > -- > 2.9.3 I think the code is good. But I don't understand the whole idea. An API mea= ns APP need call it. When should APP call This API? Does APP need to check = after sending every packet? Or just call it periodically?=20