[libvirt] [PATCH v3 1/4] Gathering vhostuser interface stats with ovs
Michal Privoznik
mprivozn at redhat.com
Thu Dec 8 12:51:13 UTC 2016
On 18.11.2016 23:51, Mehdi Abaakouk wrote:
> From: Mehdi Abaakouk <sileht at redhat.com>
>
> When vhostuser interfaces are used, the interface statistics
> are not available in /proc/net/dev.
>
> This change looks at the openvswitch interfaces statistics
> tables to provide this information for vhostuser interface.
>
> Note that in openvswitch world drop/error doesn't always make sense
> for some interface type. When these informations are not available we
> set them to 0 on the virDomainInterfaceStats.
> ---
> src/libvirt_private.syms | 1 +
> src/qemu/qemu_driver.c | 29 ++++++++---
> src/util/virnetdevopenvswitch.c | 106 ++++++++++++++++++++++++++++++++++++++++
> src/util/virnetdevopenvswitch.h | 4 ++
> 4 files changed, 133 insertions(+), 7 deletions(-)
>
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index baff82b..aa27f78 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -2034,6 +2034,7 @@ virNetDevMidonetUnbindPort;
> # util/virnetdevopenvswitch.h
> virNetDevOpenvswitchAddPort;
> virNetDevOpenvswitchGetMigrateData;
> +virNetDevOpenvswitchInterfaceStats;
> virNetDevOpenvswitchRemovePort;
> virNetDevOpenvswitchSetMigrateData;
>
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index d039255..87ca09d 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -66,6 +66,7 @@
> #include "virhostcpu.h"
> #include "virhostmem.h"
> #include "virstats.h"
> +#include "virnetdevopenvswitch.h"
> #include "capabilities.h"
> #include "viralloc.h"
> #include "viruuid.h"
> @@ -10975,6 +10976,7 @@ qemuDomainInterfaceStats(virDomainPtr dom,
> virDomainInterfaceStatsPtr stats)
> {
> virDomainObjPtr vm;
> + virDomainNetDefPtr net = NULL;
> size_t i;
> int ret = -1;
>
> @@ -10994,16 +10996,21 @@ qemuDomainInterfaceStats(virDomainPtr dom,
> for (i = 0; i < vm->def->nnets; i++) {
> if (vm->def->nets[i]->ifname &&
> STREQ(vm->def->nets[i]->ifname, path)) {
> - ret = 0;
> + net = vm->def->nets[i];
> break;
> }
> }
>
> - if (ret == 0)
> - ret = virNetInterfaceStats(path, stats);
> - else
> + if (net) {
> + if (net->type == VIR_DOMAIN_NET_TYPE_VHOSTUSER) {
> + ret = virNetDevOpenvswitchInterfaceStats(path, stats);
> + } else {
> + ret = virNetInterfaceStats(path, stats);
> + }
> + } else {
> virReportError(VIR_ERR_INVALID_ARG,
> _("invalid path, '%s' is not a known interface"), path);
> + }
>
Oh my. Not your fault but this looks ugly. It has even before you've
touched it.
BTW: maybe I am misreading something but my understanding of vhost-user
is that it can be plugged into any type of bridge (e.g. snabb). How does
this work then if we run ovs-vsctl then? Do you perhaps have a set of
steps how can I test this feature? Because so far I've used
vhost-user-bridge helper from qemu repo but this will not work with it.
> cleanup:
> virDomainObjEndAPI(&vm);
> @@ -19140,9 +19147,17 @@ qemuDomainGetStatsInterface(virQEMUDriverPtr driver ATTRIBUTE_UNUSED,
> QEMU_ADD_NAME_PARAM(record, maxparams,
> "net", "name", i, dom->def->nets[i]->ifname);
>
> - if (virNetInterfaceStats(dom->def->nets[i]->ifname, &tmp) < 0) {
> - virResetLastError();
> - continue;
> + if (dom->def->nets[i]->type == VIR_DOMAIN_NET_TYPE_VHOSTUSER) {
> + if (virNetDevOpenvswitchInterfaceStats(dom->def->nets[i]->ifname,
> + &tmp) < 0) {
> + virResetLastError();
> + continue;
> + }
> + } else {
> + if (virNetInterfaceStats(dom->def->nets[i]->ifname, &tmp) < 0) {
> + virResetLastError();
> + continue;
> + }
> }
>
> QEMU_ADD_NET_PARAM(record, maxparams, i,
> diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c
> index 9283bbb..db8b542 100644
> --- a/src/util/virnetdevopenvswitch.c
> +++ b/src/util/virnetdevopenvswitch.c
> @@ -24,6 +24,8 @@
>
> #include <config.h>
>
> +#include <stdio.h>
> +
> #include "virnetdevopenvswitch.h"
> #include "vircommand.h"
> #include "viralloc.h"
> @@ -270,3 +272,107 @@ int virNetDevOpenvswitchSetMigrateData(char *migrate, const char *ifname)
> virCommandFree(cmd);
> return ret;
> }
> +
> +/**
> + * virNetDevOpenvswitchInterfaceStats:
> + * @ifname: the name of the interface
> + * @stats: the retreived domain interface stat
> + *
> + * Retrieves the OVS interfaces stats
> + *
> + * Returns 0 in case of success or -1 in case of failure
> + */
> +int
> +virNetDevOpenvswitchInterfaceStats(const char *ifname,
> + virDomainInterfaceStatsPtr stats)
> +{
> + virCommandPtr cmd = NULL;
> + char *output;
> + long long rx_bytes;
> + long long rx_packets;
> + long long tx_bytes;
> + long long tx_packets;
> + long long rx_errs;
> + long long rx_drop;
> + long long tx_errs;
> + long long tx_drop;
> + int ret = -1;
> +
> + // Just ensure the interface exists in ovs
> + cmd = virCommandNewArgList(OVSVSCTL, "--timeout=5",
> + "get", "Interface", ifname,
> + "name", NULL);
> + virCommandSetOutputBuffer(cmd, &output);
> +
> + if (virCommandRun(cmd, NULL) < 0) {
> + // no ovs-vsctl or interface 'ifname' doesn't exists in ovs
We prefer c89 style of comments.
> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> + _("Interface not found"));
> + goto cleanup;
> + }
> +
> + VIR_FREE(output);
> + virCommandFree(cmd);
> +
> + cmd = virCommandNewArgList(OVSVSCTL, "--timeout=5",
> + "get", "Interface", ifname,
> + "statistics:rx_bytes",
> + "statistics:rx_packets",
> + "statistics:tx_bytes",
> + "statistics:tx_packets", NULL);
> + virCommandSetOutputBuffer(cmd, &output);
> +
> + if (virCommandRun(cmd, NULL) < 0) {
> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> + _("Interface doesn't have statistics"));
> + goto cleanup;
> + }
> +
> + // The TX/RX fields appear to be swapped here because this is the host view.
> + if (sscanf(output, "%lld\n%lld\n%lld\n%lld\n",
> + &tx_bytes, &tx_packets, &rx_bytes, &rx_packets) != 4) {
> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> + _("Fail to parse ovs-vsctl output"));
> + goto cleanup;
> + }
> +
> + stats->rx_bytes = rx_bytes;
> + stats->rx_packets = rx_packets;
> + stats->tx_bytes = tx_bytes;
> + stats->tx_packets = tx_packets;
> +
> + VIR_FREE(output);
> + virCommandFree(cmd);
> +
> + cmd = virCommandNewArgList(OVSVSCTL, "--timeout=5",
> + "get", "Interface", ifname,
> + "statistics:rx_errors",
> + "statistics:rx_dropped",
> + "statistics:tx_errors",
> + "statistics:tx_dropped", NULL);
> + virCommandSetOutputBuffer(cmd, &output);
> + if (virCommandRun(cmd, NULL) < 0) {
> + // This interface don't have errors or dropped, so set them to 0
> + stats->rx_errs = 0;
> + stats->rx_drop = 0;
> + stats->tx_errs = 0;
> + stats->tx_drop = 0;
> + } else if (sscanf(output, "%lld\n%lld\n%lld\n%lld\n",
> + &tx_errs, &tx_drop, &rx_errs, &rx_drop) == 4) {
> + stats->rx_errs = rx_errs;
> + stats->rx_drop = rx_drop;
> + stats->tx_errs = tx_errs;
> + stats->tx_drop = tx_drop;
> + ret = 0;
> + } else {
> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> + _("Fail to parse ovs-vsctl output"));
> + goto cleanup;
> + }
> + ret = 0;
> +
> + cleanup:
> + VIR_FREE(output);
> + virCommandFree(cmd);
> + return ret;
> +}
Michal
More information about the libvir-list
mailing list