On 10/06/2017 05:45 PM, antonio.fische...@intel.com wrote: > 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 <ktray...@redhat.com> > CC: Aaron Conole <acon...@redhat.com> > CC: Darrell Ball <dlu...@gmail.com> > Reported-by: Ciara Loftus <ciara.lof...@intel.com> > Tested-by: Ciara Loftus <ciara.lof...@intel.com> > Fixes: d555d9bded5f ("netdev-dpdk: Create separate memory pool for each > port.") > Signed-off-by: Antonio Fischetti <antonio.fische...@intel.com> > --- > 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 | 27 ++++++++++++++------------- > 1 file changed, 14 insertions(+), 13 deletions(-) > > diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c > index c60f46f..80a6ff3 100644 > --- a/lib/netdev-dpdk.c > +++ b/lib/netdev-dpdk.c > @@ -508,7 +508,7 @@ 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) { > @@ -530,8 +530,6 @@ 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 +557,7 @@ 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 +571,7 @@ 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) &&
This makes it necessary for the caller to set mp_exists=false before calling this function, otherwise it will operate incorrectly. It would be better to set it at the start of the function and not have a dependency on calls higher up the chain, or else just change the return value to mp_exists. > (rte_errno == ENOMEM && (dmp->mp_size /= 2) >= MIN_NB_MBUF)); > > rte_free(dmp); > @@ -581,12 +579,12 @@ 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 +618,17 @@ 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 = false; > > - 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) { > + return EEXIST; > } else { > dpdk_mp_put(dev->dpdk_mp); > dev->dpdk_mp = mp; > @@ -3207,7 +3208,7 @@ 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) { err will be returned from this function, I don't think that's correct. Actually now I see a mail on ML reporting an issue with this patch and I think it's because EEXISTS is reported from this function. It's not a reconfigure error that the mempool is reused, it could be reused if txqs were changed or if new mtu is within the rounded value. > goto out; > } > > @@ -3247,12 +3248,12 @@ 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; > _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev