3:54 a.m.
We run 'ovs-vsctl' nine times (first to find if interface is
there and then eight times = for each stats member separately).
This is very inefficient. I've found a way to run it once and
with a bit of help from virJSON module we can parse out stats
we need.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/util/virnetdevopenvswitch.c | 111 +++++++++++++++++++++-----------
1 file changed, 74 insertions(+), 37 deletions(-)
diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c
index c99ecfbf15..0fe64bedab 100644
--- a/src/util/virnetdevopenvswitch.c
+++ b/src/util/virnetdevopenvswitch.c
@@ -28,6 +28,7 @@
#include "virmacaddr.h"
#include "virstring.h"
#include "virlog.h"
+#include "virjson.h"
#define VIR_FROM_THIS VIR_FROM_NONE
@@ -311,58 +312,94 @@ int
virNetDevOpenvswitchInterfaceStats(const char *ifname,
virDomainInterfaceStatsPtr stats)
{
- char *tmp;
- bool gotStats = false;
VIR_AUTOPTR(virCommand) cmd = NULL;
VIR_AUTOFREE(char *) output = NULL;
+ VIR_AUTOPTR(virJSONValue) jsonStats = NULL;
+ virJSONValuePtr jsonMap = NULL;
+ size_t i;
- /* Just ensure the interface exists in ovs */
cmd = virCommandNew(OVSVSCTL);
virNetDevOpenvswitchAddTimeout(cmd);
- virCommandAddArgList(cmd, "get", "Interface", ifname,
"name", NULL);
+ virCommandAddArgList(cmd, "--if-exists", "--format=list",
"--data=json",
+ "--no-headings", "--columns=statistics",
"list",
+ "Interface", ifname, NULL);
virCommandSetOutputBuffer(cmd, &output);
- if (virCommandRun(cmd, NULL) < 0) {
+ /* The above command returns either:
+ * 1) empty string if @ifname doesn't exist, or
+ * 2) a JSON array, for instance:
+ *
["map",[["collisions",0],["rx_bytes",0],["rx_crc_err",0],["rx_dropped",0],
+ *
["rx_errors",0],["rx_frame_err",0],["rx_over_err",0],["rx_packets",0],
+ *
["tx_bytes",12406],["tx_dropped",0],["tx_errors",0],["tx_packets",173]]]
+ */
+
+ if (virCommandRun(cmd, NULL) < 0 ||
+ STREQ_NULLABLE(output, "")) {
/* no ovs-vsctl or interface 'ifname' doesn't exists in ovs */
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Interface not found"));
return -1;
}
-#define GET_STAT(name, member) \
- do { \
- VIR_FREE(output); \
- virCommandFree(cmd); \
- cmd = virCommandNew(OVSVSCTL); \
- virNetDevOpenvswitchAddTimeout(cmd); \
- virCommandAddArgList(cmd, "--if-exists", "get",
"Interface", \
- ifname, "statistics:" name, NULL); \
- virCommandSetOutputBuffer(cmd, &output); \
- if (virCommandRun(cmd, NULL) < 0 || !output || !*output || *output ==
'\n') { \
- stats->member = -1; \
- } else { \
- if (virStrToLong_ll(output, &tmp, 10, &stats->member) < 0 || \
- *tmp != '\n') { \
- virReportError(VIR_ERR_INTERNAL_ERROR, "%s", \
- _("Fail to parse ovs-vsctl output")); \
- return -1; \
- } \
- gotStats = true; \
- } \
- } while (0)
+ if (!(jsonStats = virJSONValueFromString(output)) ||
+ !virJSONValueIsArray(jsonStats) ||
+ !(jsonMap = virJSONValueArrayGet(jsonStats, 1))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Unable to parse ovs-vsctl output"));
+ return -1;
+ }
- /* The TX/RX fields appear to be swapped here
- * because this is the host view. */
- GET_STAT("rx_bytes", tx_bytes);
- GET_STAT("rx_packets", tx_packets);
- GET_STAT("rx_errors", tx_errs);
- GET_STAT("rx_dropped", tx_drop);
- GET_STAT("tx_bytes", rx_bytes);
- GET_STAT("tx_packets", rx_packets);
- GET_STAT("tx_errors", rx_errs);
- GET_STAT("tx_dropped", rx_drop);
+ stats->rx_bytes = stats->rx_packets = stats->rx_errs = stats->rx_drop =
-1;
+ stats->tx_bytes = stats->tx_packets = stats->tx_errs = stats->tx_drop =
-1;
- if (!gotStats) {
+ for (i = 0; i < virJSONValueArraySize(jsonMap); i++) {
+ virJSONValuePtr item = virJSONValueArrayGet(jsonMap, i);
+ virJSONValuePtr jsonKey;
+ virJSONValuePtr jsonVal;
+ const char *key;
+ long long val;
+
+ if (!item ||
+ (!(jsonKey = virJSONValueArrayGet(item, 0))) ||
+ (!(jsonVal = virJSONValueArrayGet(item, 1))) ||
+ (!(key = virJSONValueGetString(jsonKey))) ||
+ (virJSONValueGetNumberLong(jsonVal, &val) < 0)) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Malformed ovs-vsctl output"));
+ return -1;
+ }
+
+ /* The TX/RX fields appear to be swapped here
+ * because this is the host view. */
+ if (STREQ(key, "rx_bytes")) {
+ stats->tx_bytes = val;
+ } else if (STREQ(key, "rx_packets")) {
+ stats->tx_packets = val;
+ } else if (STREQ(key, "rx_errors")) {
+ stats->tx_errs = val;
+ } else if (STREQ(key, "rx_dropped")) {
+ stats->tx_drop = val;
+ } else if (STREQ(key, "tx_bytes")) {
+ stats->rx_bytes = val;
+ } else if (STREQ(key, "tx_packets")) {
+ stats->rx_packets = val;
+ } else if (STREQ(key, "tx_errors")) {
+ stats->rx_errs = val;
+ } else if (STREQ(key, "tx_dropped")) {
+ stats->rx_drop = val;
+ } else {
+ VIR_DEBUG("Unused ovs-vsctl stat key=%s val=%lld", key, val);
+ }
+ }
+
+ if (stats->rx_bytes == -1 &&
+ stats->rx_packets == -1 &&
+ stats->rx_errs == -1 &&
+ stats->rx_drop == -1 &&
+ stats->tx_bytes == -1 &&
+ stats->tx_packets == -1 &&
+ stats->tx_errs == -1 &&
+ stats->tx_drop == -1) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Interface doesn't have any statistics"));
return -1;
--
2.21.0