Re: [PATCH v2] util: support PCI passthrough net device stats collection

Collect PCI passthrough net device stats from kernel by netlink API. Currently, libvirt can not get PCI passthrough net device stats, run command: #virsh domifstat instance --interface=52:54:00:2d:b2:35 error: Failed to get interface stats instance 52:54:00:2d:b2:35 error: internal error: Interface name not provided The PCI device(usually SR-IOV virtual function device) is detached while it's used in PCI passthrough mode. And we can not parse this device from /proc/net/dev any more. In this patch, libvirt check net device is VF of not firstly, then query virNetDevVFInterfaceStats(new API). virNetDevVFInterfaceStats parses VFs info of all PFs, compares MAC address until the two MAC addresses match. '#ip -s link show' can get the same result. Instead of parsing the output result, implement this feature by libnl API. Notice that this feature deponds on driver of PF. Test on Mellanox ConnectX-4 Lx, it works well. Also test on Intel Corporation 82599ES, it works, but only get 0. (ip-link command get the same result). Signed-off-by: zhenwei pi <pizhenwei(a)bytedance.com&gt; --- src/libvirt_private.syms | 1 + src/qemu/qemu_driver.c | 3 ++ src/util/virnetdev.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++ src/util/virnetdev.h | 5 ++ 4 files changed, 146 insertions(+) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index bdbe3431b8..bcc40b8d69 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2585,6 +2585,7 @@ virNetDevSetRcvMulti; virNetDevSetupControl; virNetDevSysfsFile; virNetDevValidateConfig; +virNetDevVFInterfaceStats; # util/virnetdevbandwidth.h diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index ae715c01d7..f554010c40 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -10196,6 +10196,9 @@ qemuDomainInterfaceStats(virDomainPtr dom, if (virDomainNetGetActualType(net) == VIR_DOMAIN_NET_TYPE_VHOSTUSER) { if (virNetDevOpenvswitchInterfaceStats(net->ifname, stats) < 0) goto cleanup; + } else if (virDomainNetGetActualType(net) == VIR_DOMAIN_NET_TYPE_HOSTDEV) { + if (virNetDevVFInterfaceStats(&net->mac, stats) < 0) + goto cleanup; } else { if (virNetDevTapInterfaceStats(net->ifname, stats, !virDomainNetTypeSharesHostView(net)) < 0) diff --git a/src/util/virnetdev.c b/src/util/virnetdev.c index e1a4cc2bef..377f25aae7 100644 --- a/src/util/virnetdev.c +++ b/src/util/virnetdev.c @@ -1489,6 +1489,7 @@ static struct nla_policy ifla_vf_policy[IFLA_VF_MAX+1] = { .maxlen = sizeof(struct ifla_vf_mac) }, [IFLA_VF_VLAN] = { .type = NLA_UNSPEC, .maxlen = sizeof(struct ifla_vf_vlan) }, + [IFLA_VF_STATS] = { .type = NLA_NESTED }, }; @@ -2265,6 +2266,132 @@ virNetDevSetNetConfig(const char *linkdev, int vf, return 0; } +static struct nla_policy ifla_vfstats_policy[IFLA_VF_STATS_MAX+1] = { + [IFLA_VF_STATS_RX_PACKETS] = { .type = NLA_U64 }, + [IFLA_VF_STATS_TX_PACKETS] = { .type = NLA_U64 }, + [IFLA_VF_STATS_RX_BYTES] = { .type = NLA_U64 }, + [IFLA_VF_STATS_TX_BYTES] = { .type = NLA_U64 }, + [IFLA_VF_STATS_BROADCAST] = { .type = NLA_U64 }, + [IFLA_VF_STATS_MULTICAST] = { .type = NLA_U64 }, +}; + +static int +virNetDevParseVfStats(struct nlattr **tb, virMacAddrPtr mac, + virDomainInterfaceStatsPtr stats) +{ + int ret = -1, len; + struct ifla_vf_mac *vf_lladdr; + struct nlattr *nla, *t[IFLA_VF_MAX+1]; + struct nlattr *stb[IFLA_VF_STATS_MAX+1]; + + if (tb == NULL || mac == NULL || stats == NULL) { + return -1; + } + + if (!tb[IFLA_VFINFO_LIST]) + return -1; + + len = nla_len(tb[IFLA_VFINFO_LIST]); + + for (nla = nla_data(tb[IFLA_VFINFO_LIST]); nla_ok(nla, len); + nla = nla_next(nla, &len)) { + ret = nla_parse(t, IFLA_VF_MAX, nla_data(nla), nla_len(nla), + ifla_vf_policy); + if (ret < 0) + return -1; + + if (t[IFLA_VF_MAC] == NULL) { + continue; + } + + vf_lladdr = nla_data(t[IFLA_VF_MAC]); + if (virMacAddrCmpRaw(mac, vf_lladdr->mac)) { + continue; + } + + if (t[IFLA_VF_STATS]) { + ret = nla_parse_nested(stb, IFLA_VF_STATS_MAX, + t[IFLA_VF_STATS], + ifla_vfstats_policy); + if (ret < 0) + return -1; + + stats->rx_bytes = nla_get_u64(stb[IFLA_VF_STATS_RX_BYTES]); + stats->tx_bytes = nla_get_u64(stb[IFLA_VF_STATS_TX_BYTES]); + stats->rx_packets = nla_get_u64(stb[IFLA_VF_STATS_RX_PACKETS]); + stats->tx_packets = nla_get_u64(stb[IFLA_VF_STATS_TX_PACKETS]); + } + return 0; + } + + return ret; +} + +/** + * virNetDevVFInterfaceStats: + * @mac: MAC address of the VF interface + * @stats: returns stats of the VF interface + * + * Get the VF interface from kernel by netlink. + * Returns 0 on success, -1 on failure. + */ +int +virNetDevVFInterfaceStats(virMacAddrPtr mac, + virDomainInterfaceStatsPtr stats) +{ + FILE *fp; + char line[256], *colon, *ifname; + int rc = -1; + void *nlData = NULL; + struct nlattr *tb[IFLA_MAX + 1] = {NULL, }; + char *sysfsDevicePath = NULL; + + fp = fopen("/proc/net/dev", "r"); + if (!fp) { + virReportSystemError(errno, "%s", + _("Could not open /proc/net/dev")); + return -1; + } + + /* get all PCI net devices, and parse VFs list from netlink API. + * compare MAC address, collect device stats if matching. + */ + while (fgets(line, sizeof(line), fp)) { + /* The line looks like: + * " eth0:..." + * Split it at the colon. and strip blank from head. + */ + colon = strchr(line, ':'); + if (!colon) + continue; + *colon = '\0'; + ifname = line; + while ((*ifname == ' ') && (ifname < colon)) + ifname++;

+ + if (virNetDevSysfsFile(&sysfsDevicePath, ifname, "device") < 0) + break; + + if (virNetDevIsPCIDevice(sysfsDevicePath)) { + rc = virNetlinkDumpLink(ifname, -1, &nlData, tb, 0, 0); + if (rc < 0) { + rc = -1; + goto cleanup; + } + + rc = virNetDevParseVfStats(tb, mac, stats); + VIR_FREE(nlData); + if (rc == 0) + goto cleanup; + } + VIR_FREE(sysfsDevicePath); + } + + cleanup: + VIR_FREE(sysfsDevicePath); + VIR_FORCE_FCLOSE(fp); + return rc; +}