Hi all, Just pinging for feedback for this patch. If we are to include this for branch 2.9 as a bug fix I think we need feedback quite soon.
Have people had time to validate and review? Thanks Ian > -----Original Message----- > From: Stokes, Ian > Sent: Thursday, February 8, 2018 11:39 AM > To: d...@openvswitch.org > Cc: Stokes, Ian <ian.sto...@intel.com>; antonio.fische...@gmail.com; Ilya > Maximets <i.maxim...@samsung.com>; Kevin Traynor <ktray...@redhat.com>; > Jan Scheurich <jan.scheur...@ericsson.com> > Subject: [RFC Patch v1] netdev-dpdk: Reintroduce shared mempools. > > This commit manually reverts the current per port mempool model to the > previous shared mempool model for DPDK ports. > > OVS previously used a shared mempool model for ports with the same MTU > configuration. This was replaced by a per port mempool model to address > issues flagged by users such as: > > https://mail.openvswitch.org/pipermail/ovs-discuss/2016- > September/042560.html > > However the per port model has a number of issues including: > > 1. Requires an increase in memory resource requirements to support the > same number of ports as the shared port model. > 2. Incorrect algorithm for mbuf provisioning for each mempool. > > These are considered blocking factors for current deployments of OVS when > upgrading to OVS 2.9 as a memory redimensioning will be required. This may > not be possible for users. > > For clarity, the commits whose changes are removed include the > following: > > netdev-dpdk: Create separate memory pool for each port: d555d9b > netdev-dpdk: fix management of pre-existing mempools: b6b26021d Fix > mempool names to reflect socket id: f06546a > netdev-dpdk: skip init for existing mempools: 837c176 > netdev-dpdk: manage failure in mempool name creation: 65056fd > netdev-dpdk: Reword mp_size as n_mbufs: ad9b5b9 > netdev-dpdk: Rename dpdk_mp_put as dpdk_mp_free: a08a115 > netdev-dpdk: Fix mp_name leak on snprintf failure: ec6edc8 > netdev-dpdk: Fix dpdk_mp leak in case of EEXIST: 173ef76 > netdev-dpdk: Factor out struct dpdk_mp: 24e78f9 > netdev-dpdk: Remove unused MAX_NB_MBUF: bc57ed9 > netdev-dpdk: Fix mempool creation with large MTU: af5b0da > > Due to the number of commits and period of time they were introduced over, > a simple revert was not possible. All code from the commits above is > removed and the shared mempool code reintroduced as it was before its > replacement. > > Code introduced by commit > > netdev-dpdk: Add debug appctl to get mempool information: be48173 > > has been modified to work with the shared mempool model. > > Cc: antonio.fische...@gmail.com > Cc: Ilya Maximets <i.maxim...@samsung.com> > Cc: Kevin Traynor <ktray...@redhat.com> > Cc: Jan Scheurich <jan.scheur...@ericsson.com> > Signed-off-by: Ian Stokes <ian.sto...@intel.com> > --- > lib/netdev-dpdk.c | 246 ++++++++++++++++++++++++++++++------------------- > ----- > 1 file changed, 138 insertions(+), 108 deletions(-) > > diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c index 94fb163..6f3378b > 100644 > --- a/lib/netdev-dpdk.c > +++ b/lib/netdev-dpdk.c > @@ -91,13 +91,24 @@ static struct vlog_rate_limit rl = > VLOG_RATE_LIMIT_INIT(5, 20); > #define NETDEV_DPDK_MBUF_ALIGN 1024 > #define NETDEV_DPDK_MAX_PKT_LEN 9728 > > -/* Min number of packets in the mempool. OVS tries to allocate a mempool > with > - * roughly estimated number of mbufs: if this fails (because the system > doesn't > - * have enough hugepages) we keep halving the number until the allocation > - * succeeds or we reach MIN_NB_MBUF */ > +/* Max and min number of packets in the mempool. OVS tries to allocate > +a > + * mempool with MAX_NB_MBUF: if this fails (because the system doesn't > +have > + * enough hugepages) we keep halving the number until the allocation > +succeeds > + * or we reach MIN_NB_MBUF */ > + > +#define MAX_NB_MBUF (4096 * 64) > #define MIN_NB_MBUF (4096 * 4) > #define MP_CACHE_SZ RTE_MEMPOOL_CACHE_MAX_SIZE > > +/* MAX_NB_MBUF can be divided by 2 many times, until MIN_NB_MBUF */ > +BUILD_ASSERT_DECL(MAX_NB_MBUF % ROUND_DOWN_POW2(MAX_NB_MBUF / > MIN_NB_MBUF) > + == 0); > + > +/* The smallest possible NB_MBUF that we're going to try should be a > +multiple > + * of MP_CACHE_SZ. This is advised by DPDK documentation. */ > +BUILD_ASSERT_DECL((MAX_NB_MBUF / ROUND_DOWN_POW2(MAX_NB_MBUF / > MIN_NB_MBUF)) > + % MP_CACHE_SZ == 0); > + > /* > * DPDK XSTATS Counter names definition > */ > @@ -295,6 +306,19 @@ static struct ovs_list dpdk_list > OVS_GUARDED_BY(dpdk_mutex) static struct ovs_mutex dpdk_mp_mutex > OVS_ACQ_AFTER(dpdk_mutex) > = OVS_MUTEX_INITIALIZER; > > +static struct ovs_list dpdk_mp_list OVS_GUARDED_BY(dpdk_mp_mutex) > + = OVS_LIST_INITIALIZER(&dpdk_mp_list); > + > + > +struct dpdk_mp { > + struct rte_mempool *mp; > + int mtu; > + int socket_id; > + int refcount; > + struct ovs_list list_node OVS_GUARDED_BY(dpdk_mp_mutex); }; > + > + > /* There should be one 'struct dpdk_tx_queue' created for > * each cpu core. */ > struct dpdk_tx_queue { > @@ -371,7 +395,7 @@ struct netdev_dpdk { > > PADDED_MEMBERS_CACHELINE_MARKER(CACHE_LINE_SIZE, cacheline1, > struct ovs_mutex mutex OVS_ACQ_AFTER(dpdk_mutex); > - struct rte_mempool *mp; > + struct dpdk_mp *dpdk_mp; > > /* virtio identifier for vhost devices */ > ovsrcu_index vid; > @@ -510,133 +534,132 @@ ovs_rte_pktmbuf_init(struct rte_mempool *mp > OVS_UNUSED, > dp_packet_init_dpdk((struct dp_packet *) pkt, pkt->buf_len); } > > -/* Returns a valid pointer when either of the following is true: > - * - a new mempool was just created; > - * - a matching mempool already exists. */ -static struct rte_mempool * > -dpdk_mp_create(struct netdev_dpdk *dev, int mtu) -{ > - char mp_name[RTE_MEMPOOL_NAMESIZE]; > - const char *netdev_name = netdev_get_name(&dev->up); > - int socket_id = dev->requested_socket_id; > - uint32_t n_mbufs; > - uint32_t hash = hash_string(netdev_name, 0); > - struct rte_mempool *mp = NULL; > - > - /* > - * XXX: rough estimation of number of mbufs required for this port: > - * <packets required to fill the device rxqs> > - * + <packets that could be stuck on other ports txqs> > - * + <packets in the pmd threads> > - * + <additional memory for corner cases> > +static struct dpdk_mp * > +dpdk_mp_create(int socket_id, int mtu) > +{ > + struct dpdk_mp *dmp; > + unsigned mp_size; > + char *mp_name; > + > + dmp = dpdk_rte_mzalloc(sizeof *dmp); > + if (!dmp) { > + return NULL; > + } > + dmp->socket_id = socket_id; > + dmp->mtu = mtu; > + dmp->refcount = 1; > + /* XXX: this is a really rough method of provisioning memory. > + * It's impossible to determine what the exact memory requirements > are > + * when the number of ports and rxqs that utilize a particular > mempool can > + * change dynamically at runtime. For now, use this rough heurisitic. > */ > - n_mbufs = dev->requested_n_rxq * dev->requested_rxq_size > - + dev->requested_n_txq * dev->requested_txq_size > - + MIN(RTE_MAX_LCORE, dev->requested_n_rxq) * > NETDEV_MAX_BURST > - + MIN_NB_MBUF; > + if (mtu >= ETHER_MTU) { > + mp_size = MAX_NB_MBUF; > + } else { > + mp_size = MIN_NB_MBUF; > + } > > - ovs_mutex_lock(&dpdk_mp_mutex); > do { > - /* Full DPDK memory pool name must be unique and cannot be > - * longer than RTE_MEMPOOL_NAMESIZE. */ > - int ret = snprintf(mp_name, RTE_MEMPOOL_NAMESIZE, > - "ovs%08x%02d%05d%07u", > - hash, socket_id, mtu, n_mbufs); > - if (ret < 0 || ret >= RTE_MEMPOOL_NAMESIZE) { > - VLOG_DBG("snprintf returned %d. " > - "Failed to generate a mempool name for \"%s\". " > - "Hash:0x%x, socket_id: %d, mtu:%d, mbufs:%u.", > - ret, netdev_name, hash, socket_id, mtu, n_mbufs); > - break; > + mp_name = xasprintf("ovs_mp_%d_%d_%u", dmp->mtu, dmp->socket_id, > + mp_size); > + > + dmp->mp = rte_pktmbuf_pool_create(mp_name, mp_size, > + MP_CACHE_SZ, > + sizeof (struct dp_packet) > + - sizeof (struct rte_mbuf), > + MBUF_SIZE(mtu) > + - sizeof(struct dp_packet), > + socket_id); > + if (dmp->mp) { > + VLOG_DBG("Allocated \"%s\" mempool with %u mbufs", > + mp_name, mp_size); > } > + free(mp_name); > + if (dmp->mp) { > + /* rte_pktmbuf_pool_create has done some initialization of > the > + * rte_mbuf part of each dp_packet, while > ovs_rte_pktmbuf_init > + * initializes some OVS specific fields of dp_packet. > + */ > + rte_mempool_obj_iter(dmp->mp, ovs_rte_pktmbuf_init, NULL); > + return dmp; > + } > + } while (rte_errno == ENOMEM && (mp_size /= 2) >= MIN_NB_MBUF); > > - VLOG_DBG("Port %s: Requesting a mempool of %u mbufs " > - "on socket %d for %d Rx and %d Tx queues.", > - netdev_name, n_mbufs, socket_id, > - dev->requested_n_rxq, dev->requested_n_txq); > + rte_free(dmp); > + return NULL; > +} > > - mp = rte_pktmbuf_pool_create(mp_name, n_mbufs, MP_CACHE_SZ, > - sizeof (struct dp_packet) - sizeof (struct rte_mbuf), > - MBUF_SIZE(mtu) - sizeof(struct dp_packet), socket_id); > +static struct dpdk_mp * > +dpdk_mp_get(int socket_id, int mtu) > +{ > + struct dpdk_mp *dmp; > > - if (mp) { > - VLOG_DBG("Allocated \"%s\" mempool with %u mbufs", > - mp_name, n_mbufs); > - /* rte_pktmbuf_pool_create has done some initialization of > the > - * rte_mbuf part of each dp_packet. Some OvS specific fields > - * of the packet still need to be initialized by > - * ovs_rte_pktmbuf_init. */ > - rte_mempool_obj_iter(mp, ovs_rte_pktmbuf_init, NULL); > - } else if (rte_errno == EEXIST) { > - /* A mempool with the same name already exists. We just > - * retrieve its pointer to be returned to the caller. */ > - mp = rte_mempool_lookup(mp_name); > - /* As the mempool create returned EEXIST we can expect the > - * lookup has returned a valid pointer. If for some reason > - * that's not the case we keep track of it. */ > - VLOG_DBG("A mempool with name \"%s\" already exists at %p.", > - mp_name, mp); > - } else { > - VLOG_ERR("Failed mempool \"%s\" create request of %u mbufs", > - mp_name, n_mbufs); > + ovs_mutex_lock(&dpdk_mp_mutex); > + LIST_FOR_EACH (dmp, list_node, &dpdk_mp_list) { > + if (dmp->socket_id == socket_id && dmp->mtu == mtu) { > + dmp->refcount++; > + goto out; > } > - } while (!mp && rte_errno == ENOMEM && (n_mbufs /= 2) >= > MIN_NB_MBUF); > + } > + > + dmp = dpdk_mp_create(socket_id, mtu); > + if (dmp) { > + ovs_list_push_back(&dpdk_mp_list, &dmp->list_node); > + } > + > +out: > > ovs_mutex_unlock(&dpdk_mp_mutex); > - return mp; > + > + return dmp; > } > > /* Release an existing mempool. */ > static void > -dpdk_mp_free(struct rte_mempool *mp) > +dpdk_mp_put(struct dpdk_mp *dmp) > { > - if (!mp) { > + if (!dmp) { > return; > } > > ovs_mutex_lock(&dpdk_mp_mutex); > - VLOG_DBG("Releasing \"%s\" mempool", mp->name); > - rte_mempool_free(mp); > + ovs_assert(dmp->refcount); > + > + if (! --dmp->refcount) { > + ovs_list_remove(&dmp->list_node); > + rte_mempool_free(dmp->mp); > + rte_free(dmp); > + } > ovs_mutex_unlock(&dpdk_mp_mutex); > } > > -/* Tries to allocate a new mempool - or re-use an existing one where > - * appropriate - on requested_socket_id with a size determined by > - * requested_mtu and requested Rx/Tx queues. > - * On success - or when re-using an existing mempool - the new > configuration > - * will be applied. > +/* Tries to allocate new mempool on requested_socket_id with > + * mbuf size corresponding to requested_mtu. > + * On success new configuration will be applied. > * On error, device will be left unchanged. */ static int > netdev_dpdk_mempool_configure(struct netdev_dpdk *dev) > OVS_REQUIRES(dev->mutex) > { > uint32_t buf_size = dpdk_buf_size(dev->requested_mtu); > - struct rte_mempool *mp; > - int ret = 0; > + struct dpdk_mp *mp; > > - mp = dpdk_mp_create(dev, FRAME_LEN_TO_MTU(buf_size)); > + mp = dpdk_mp_get(dev->requested_socket_id, > + FRAME_LEN_TO_MTU(buf_size)); > if (!mp) { > VLOG_ERR("Failed to create memory pool for netdev " > "%s, with MTU %d on socket %d: %s\n", > dev->up.name, dev->requested_mtu, dev- > >requested_socket_id, > - rte_strerror(rte_errno)); > - ret = rte_errno; > + rte_strerror(rte_errno)); > + return rte_errno; > } else { > - /* If a new MTU was requested and its rounded value equals the > one > - * that is currently used, then the existing mempool is returned. > */ > - if (dev->mp != mp) { > - /* A new mempool was created, release the previous one. */ > - dpdk_mp_free(dev->mp); > - } else { > - ret = EEXIST; > - } > - dev->mp = mp; > + dpdk_mp_put(dev->dpdk_mp); > + dev->dpdk_mp = mp; > dev->mtu = dev->requested_mtu; > dev->socket_id = dev->requested_socket_id; > dev->max_packet_len = MTU_TO_FRAME_LEN(dev->mtu); > } > > - return ret; > + return 0; > } > > static void > @@ -742,7 +765,8 @@ dpdk_eth_dev_queue_setup(struct netdev_dpdk *dev, int > n_rxq, int n_txq) > > for (i = 0; i < n_rxq; i++) { > diag = rte_eth_rx_queue_setup(dev->port_id, i, dev->rxq_size, > - dev->socket_id, NULL, dev->mp); > + dev->socket_id, NULL, > + dev->dpdk_mp->mp); > if (diag) { > VLOG_INFO("Interface %s rxq(%d) setup error: %s", > dev->up.name, i, rte_strerror(-diag)); @@ - > 826,7 +850,7 @@ dpdk_eth_dev_init(struct netdev_dpdk *dev) > memcpy(dev->hwaddr.ea, eth_addr.addr_bytes, ETH_ADDR_LEN); > rte_eth_link_get_nowait(dev->port_id, &dev->link); > > - mbp_priv = rte_mempool_get_priv(dev->mp); > + mbp_priv = rte_mempool_get_priv(dev->dpdk_mp->mp); > dev->buf_size = mbp_priv->mbuf_data_room_size - RTE_PKTMBUF_HEADROOM; > > /* Get the Flow control configuration for DPDK-ETH */ @@ -1079,7 > +1103,7 @@ common_destruct(struct netdev_dpdk *dev) > OVS_EXCLUDED(dev->mutex) > { > rte_free(dev->tx_q); > - dpdk_mp_free(dev->mp); > + dpdk_mp_put(dev->dpdk_mp); > > ovs_list_remove(&dev->list_node); > free(ovsrcu_get_protected(struct ingress_policer *, @@ -1823,7 > +1847,7 @@ netdev_dpdk_vhost_rxq_recv(struct netdev_rxq *rxq, > } > > nb_rx = rte_vhost_dequeue_burst(vid, qid * VIRTIO_QNUM + VIRTIO_TXQ, > - dev->mp, > + dev->dpdk_mp->mp, > (struct rte_mbuf **) batch->packets, > NETDEV_MAX_BURST); > if (!nb_rx) { > @@ -2043,7 +2067,7 @@ dpdk_do_tx_copy(struct netdev *netdev, int qid, > struct dp_packet_batch *batch) > continue; > } > > - pkts[txcnt] = rte_pktmbuf_alloc(dev->mp); > + pkts[txcnt] = rte_pktmbuf_alloc(dev->dpdk_mp->mp); > if (OVS_UNLIKELY(!pkts[txcnt])) { > dropped += cnt - i; > break; > @@ -2919,7 +2943,7 @@ netdev_dpdk_get_mempool_info(struct unixctl_conn > *conn, > ovs_mutex_lock(&dev->mutex); > ovs_mutex_lock(&dpdk_mp_mutex); > > - rte_mempool_dump(stream, dev->mp); > + rte_mempool_dump(stream, dev->dpdk_mp->mp); > > ovs_mutex_unlock(&dpdk_mp_mutex); > ovs_mutex_unlock(&dev->mutex); > @@ -3556,9 +3580,12 @@ netdev_dpdk_reconfigure(struct netdev *netdev) > > rte_eth_dev_stop(dev->port_id); > > - err = netdev_dpdk_mempool_configure(dev); > - if (err && err != EEXIST) { > - goto out; > + if (dev->mtu != dev->requested_mtu > + || dev->socket_id != dev->requested_socket_id) { > + err = netdev_dpdk_mempool_configure(dev); > + if (err) { > + goto out; > + } > } > > netdev->n_txq = dev->requested_n_txq; @@ -3596,13 +3623,16 @@ > dpdk_vhost_reconfigure_helper(struct netdev_dpdk *dev) > > netdev_dpdk_remap_txqs(dev); > > - err = netdev_dpdk_mempool_configure(dev); > - if (!err) { > - /* A new mempool was created. */ > - netdev_change_seq_changed(&dev->up); > - } else if (err != EEXIST){ > - return err; > + if (dev->requested_socket_id != dev->socket_id > + || dev->requested_mtu != dev->mtu) { > + err = netdev_dpdk_mempool_configure(dev); > + if (err) { > + return err; > + } else { > + netdev_change_seq_changed(&dev->up); > + } > } > + > if (netdev_dpdk_get_vid(dev) >= 0) { > if (dev->vhost_reconfigured == false) { > dev->vhost_reconfigured = true; > -- > 2.7.5 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev