Thanks Mark for your review, I've added my answers inline. -Antonio
> -----Original Message----- > From: Kavanagh, Mark B > Sent: Friday, October 13, 2017 4:56 PM > To: Fischetti, Antonio <[email protected]>; [email protected] > Subject: RE: [ovs-dev] [PATCH v5 1/6] netdev-dpdk: fix management of pre- > existing mempools. > > >From: [email protected] > >[mailto:[email protected]] > >On Behalf Of [email protected] > >Sent: Wednesday, October 11, 2017 5:01 PM > >To: [email protected] > >Subject: [ovs-dev] [PATCH v5 1/6] netdev-dpdk: fix management of pre-existing > >mempools. > > Hi Antonio, > > IMO, "Fix reconfiguration of pre-existing mempools" is a more > appropriate/descriptive name for this commit. > > Also, patch 3 of the series should be combined with this one. > > Apart from that, some comments inline. > > Thanks, > Mark > > > > >Fix an issue on reconfiguration of pre-existing mempools. > >This patch avoids to call dpdk_mp_put() - and erroneously > >release the mempool - when it already exists. > > > >CC: Kevin Traynor <[email protected]> > >CC: Aaron Conole <[email protected]> > >CC: Darrell Ball <[email protected]> > >Reported-by: Ciara Loftus <[email protected]> > >Tested-by: Ciara Loftus <[email protected]> > >Reported-by: Róbert Mulik <[email protected]> > >Fixes: d555d9bded5f ("netdev-dpdk: Create separate memory pool for each > >port.") > >Signed-off-by: Antonio Fischetti <[email protected]> > >--- > >I've tested this patch by > > - changing at run-time the number of Rx queues: > > ovs-vsctl set Interface dpdk0 type=dpdk options:n_rxq=4 > > > > - reducing the MTU of the dpdk ports of 1 byte to force > > the configuration of an existing mempool: > > ovs-vsctl set Interface dpdk0 mtu_request=1499 > > > >This issue was observed in a PVP test topology with dpdkvhostuserclient > >ports. It can happen also with dpdk type ports, eg by reducing the MTU > >of 1 byte. > > > >To replicate the bug scenario in the PVP case it's sufficient to > >set 1 dpdkvhostuserclient port, and just boot the VM. > > > >Below some more details on my own test setup. > > > > PVP test setup > > -------------- > >CLIENT_SOCK_DIR=/tmp > >SOCK0=dpdkvhostuser0 > >SOCK1=dpdkvhostuser1 > > > >1 PMD > >Add 2 dpdk ports, n_rxq=1 > >Add 2 vhu ports both of type dpdkvhostuserclient and specify > >vhost-server-path > > ovs-vsctl set Interface dpdkvhostuser0 options:vhost-server- > >path="$CLIENT_SOCK_DIR/$SOCK0" > > ovs-vsctl set Interface dpdkvhostuser1 options:vhost-server- > >path="$CLIENT_SOCK_DIR/$SOCK1" > > > >Set port-based rules: dpdk0 <--> vhu0 and dpdk1 <--> vhu1 > > add-flow br0 in_port=1,action=output:3 > > add-flow br0 in_port=3,action=output:1 > > add-flow br0 in_port=4,action=output:2 > > add-flow br0 in_port=2,action=output:4 > > > > Launch QEMU > > ----------- > >As OvS vhu ports are acting as clients, we must specify 'server' in the next > >command. > >VM_IMAGE=<path/to/your/vm/image> > > > > sudo -E taskset 0x3F00 $QEMU_DIR/x86_64-softmmu/qemu-system-x86_64 -name us- > >vhost-vm1 -cpu host -enable-kvm -m 4096M -object memory-backend- > >file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on -numa node,memdev=mem > >-mem-prealloc -smp 4 -drive file=$VM_IMAGE -chardev > >socket,id=char0,path=$CLIENT_SOCK_DIR/$SOCK0,server -netdev type=vhost- > >user,id=mynet1,chardev=char0,vhostforce -device virtio-net- > >pci,mac=00:00:00:00:00:01,netdev=mynet1,mrg_rxbuf=off -chardev > >socket,id=char1,path=$CLIENT_SOCK_DIR/$SOCK1,server -netdev type=vhost- > >user,id=mynet2,chardev=char1,vhostforce -device virtio-net- > >pci,mac=00:00:00:00:00:02,netdev=mynet2,mrg_rxbuf=off --nographic > > > > Expected behavior > > ----------------- > >With this fix OvS shouldn't crash. > >--- > > lib/netdev-dpdk.c | 34 +++++++++++++++++++++------------- > > 1 file changed, 21 insertions(+), 13 deletions(-) > > > >diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c > >index c60f46f..e6f3ca4 100644 > >--- a/lib/netdev-dpdk.c > >+++ b/lib/netdev-dpdk.c > >@@ -508,12 +508,13 @@ dpdk_mp_name(struct dpdk_mp *dmp) > > } > > > > static struct dpdk_mp * > >-dpdk_mp_create(struct netdev_dpdk *dev, int mtu) > >+dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool *mp_exists) > > { > > struct dpdk_mp *dmp = dpdk_rte_mzalloc(sizeof *dmp); > > if (!dmp) { > > return NULL; > > } > >+ *mp_exists = false; > > dmp->socket_id = dev->requested_socket_id; > > dmp->mtu = mtu; > > ovs_strzcpy(dmp->if_name, dev->up.name, IFNAMSIZ); > >@@ -530,8 +531,6 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu) > > + MIN(RTE_MAX_LCORE, dev->requested_n_rxq) * NETDEV_MAX_BURST > > + MIN_NB_MBUF; > > > >- bool mp_exists = false; > >- > > do { > > char *mp_name = dpdk_mp_name(dmp); > > > >@@ -559,7 +558,7 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu) > > /* 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. */ > >- mp_exists = true; > >+ *mp_exists = true; > > } else { > > VLOG_ERR("Failed mempool \"%s\" create request of %u mbufs", > > mp_name, dmp->mp_size); > >@@ -573,7 +572,7 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu) > > rte_mempool_obj_iter(dmp->mp, ovs_rte_pktmbuf_init, NULL); > > return dmp; > > } > >- } while (!mp_exists && > >+ } while (!(*mp_exists) && > > (rte_errno == ENOMEM && (dmp->mp_size /= 2) >= MIN_NB_MBUF)); > > > > rte_free(dmp); > >@@ -581,12 +580,12 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu) > > } > > > > static struct dpdk_mp * > >-dpdk_mp_get(struct netdev_dpdk *dev, int mtu) > >+dpdk_mp_get(struct netdev_dpdk *dev, int mtu, bool *mp_exists) > > { > > struct dpdk_mp *dmp; > > > > ovs_mutex_lock(&dpdk_mp_mutex); > >- dmp = dpdk_mp_create(dev, mtu); > >+ dmp = dpdk_mp_create(dev, mtu, mp_exists); > > ovs_mutex_unlock(&dpdk_mp_mutex); > > > > return dmp; > >@@ -620,14 +619,23 @@ netdev_dpdk_mempool_configure(struct netdev_dpdk *dev) > > { > > uint32_t buf_size = dpdk_buf_size(dev->requested_mtu); > > struct dpdk_mp *mp; > >+ bool mp_exists; > > This variable is unneeded - see comment below. [Antonio] I'll explain this in the next comment. > > > > >- mp = dpdk_mp_get(dev, FRAME_LEN_TO_MTU(buf_size)); > >+ mp = dpdk_mp_get(dev, FRAME_LEN_TO_MTU(buf_size), &mp_exists); > > 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)); > > return rte_errno; > >+ } else if (mp_exists) { > > Why not just use "else if (rte_errno == EEXIST)" instead (since it will have > been set by rte_pktmbuf_pool_create())? [Antonio] I preferred not to check rte_errno value because after rte_pktmbuf_pool_create() - in case of EEXIST - another fn rte_mempool_lookup() could be called, and that could also return ENOENT. > > >+ /* If a new MTU was requested and its rounded value equals the one > >+ * that is currently used, then the existing mempool is returned. > >+ * Update dev with the new values. */ > >+ dev->mtu = dev->requested_mtu; > >+ dev->socket_id = dev->requested_socket_id; > > Don't need to reassign socket_id, since it hasn't changed (by virtue of the > fact that the mempool name incorporates the socket id, and that itself hasn't > changed). [Antonio] Agree. > > >+ dev->max_packet_len = MTU_TO_FRAME_LEN(dev->mtu); > >+ return EEXIST; > > } else { > > dpdk_mp_put(dev->dpdk_mp); > > dev->dpdk_mp = mp; > >@@ -3207,7 +3215,7 @@ netdev_dpdk_reconfigure(struct netdev *netdev) > > rte_eth_dev_stop(dev->port_id); > > > > err = netdev_dpdk_mempool_configure(dev); > >- if (err) { > >+ if (err && err != EEXIST) { > > goto out; > > } > > > >@@ -3247,12 +3255,12 @@ dpdk_vhost_reconfigure_helper(struct netdev_dpdk > >*dev) > > netdev_dpdk_remap_txqs(dev); > > > > err = netdev_dpdk_mempool_configure(dev); > >- if (err) { > >- return err; > >- } else { > >+ if (!err) { > >+ /* A new mempool was created. */ > > netdev_change_seq_changed(&dev->up); > >+ } else if (err != EEXIST){ > >+ return err; > > } > >- > > if (netdev_dpdk_get_vid(dev) >= 0) { > > if (dev->vhost_reconfigured == false) { > > dev->vhost_reconfigured = true; > >-- > >2.4.11 > > > >_______________________________________________ > >dev mailing list > >[email protected] > >https://mail.openvswitch.org/mailman/listinfo/ovs-dev _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
