3:30 p.m.
This patch add new perf command to enable/disable perf event
for a guest domain.
Signed-off-by: Qiaowei Ren <qiaowei.ren(a)intel.com>
---
tools/virsh-domain.c | 128 +++++++++++++++++++++++++++++++++++++++++++++++++++
tools/virsh.pod | 20 ++++++++
2 files changed, 148 insertions(+)
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 17be5b4..0d020a7 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -8506,6 +8506,128 @@ cmdMemtune(vshControl *ctl, const vshCmd *cmd)
}
/*
+ * "perf" command
+ */
+static const vshCmdInfo info_perf[] = {
+ {.name = "help",
+ .data = N_("Get or set perf event")
+ },
+ {.name = "desc",
+ .data = N_("Get or set the current perf events for a guest"
+ " domain.\n"
+ " To get the perf events list use following command:
\n\n"
+ " virsh # perf <domain>")
+ },
+ {.name = NULL}
+};
+
+static const vshCmdOptDef opts_perf[] = {
+ {.name = "domain",
+ .type = VSH_OT_DATA,
+ .flags = VSH_OFLAG_REQ,
+ .help = N_("domain name, id or uuid")
+ },
+ {.name = "enable",
+ .type = VSH_OT_STRING,
+ .help = N_("perf events which will be enabled")
+ },
+ {.name = "disable",
+ .type = VSH_OT_STRING,
+ .help = N_("perf events which will be disabled")
+ },
+ {.name = NULL}
+};
+
+static int
+virshParseEventStr(vshControl *ctl,
+ const char *event,
+ bool state,
+ virTypedParameterPtr *params,
+ int *nparams,
+ int *maxparams)
+{
+ char **tok = NULL;
+ size_t i, ntok;
+ int ret = -1;
+
+ if (!(tok = virStringSplitCount(event, "|", 0, &ntok)))
+ return -1;
+
+ if (ntok > VIR_PERF_EVENT_LAST) {
+ vshError(ctl, _("event string '%s' has too many fields"),
event);
+ goto cleanup;
+ }
+
+ for(i = 0; i < ntok; i++) {
+ if ((*tok[i] != '\0') &&
+ virTypedParamsAddBoolean(params, nparams,
+ maxparams, tok[i], state) < 0)
+ goto cleanup;
+ }
+
+ ret = 0;
+ cleanup:
+ virStringFreeList(tok);
+ return ret;
+}
+
+static bool
+cmdPerf(vshControl *ctl, const vshCmd *cmd)
+{
+ virDomainPtr dom;
+ int nparams = 0;
+ int maxparams = 0;
+ size_t i;
+ virTypedParameterPtr params = NULL;
+ bool ret = false;
+ const char *enable = NULL, *disable = NULL;
+
+ if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
+ return false;
+
+ if (vshCommandOptStringReq(ctl, cmd, "enable", &enable) < 0 ||
+ vshCommandOptStringReq(ctl, cmd, "disable", &disable) < 0)
+ return false;
+
+ if (enable && virshParseEventStr(ctl, enable, true,
+ ¶ms, &nparams, &maxparams) < 0)
+ goto cleanup;
+
+ if (disable && virshParseEventStr(ctl, disable, false,
+ ¶ms, &nparams, &maxparams) < 0)
+ goto cleanup;
+
+ if (nparams == 0) {
+ if (virDomainGetPerfEvents(dom, ¶ms, &nparams) != 0) {
+ vshError(ctl, "%s", _("Unable to get perf events"));
+ goto cleanup;
+ }
+ for (i = 0; i < nparams; i++) {
+ if (params[i].type == VIR_TYPED_PARAM_BOOLEAN &&
+ params[i].value.b) {
+ vshPrint(ctl, "%-15s: %s\n", params[i].field,
_("enabled"));
+ } else {
+ vshPrint(ctl, "%-15s: %s\n", params[i].field,
_("disabled"));
+ }
+ }
+ } else {
+ if (virDomainSetPerfEvents(dom, params, nparams) != 0)
+ goto error;
+ }
+
+ ret = true;
+ cleanup:
+ virTypedParamsFree(params, nparams);
+ virDomainFree(dom);
+ return ret;
+
+ error:
+ vshError(ctl, "%s", _("Unable to enable/disable perf events"));
+ goto cleanup;
+}
+
+
+/*
* "numatune" command
*/
static const vshCmdInfo info_numatune[] = {
@@ -13070,6 +13192,12 @@ const vshCmdDef domManagementCmds[] = {
.info = info_memtune,
.flags = 0
},
+ {.name = "perf",
+ .handler = cmdPerf,
+ .opts = opts_perf,
+ .info = info_perf,
+ .flags = 0
+ },
{.name = "metadata",
.handler = cmdMetadata,
.opts = opts_metadata,
diff --git a/tools/virsh.pod b/tools/virsh.pod
index 2c13e04..d0bd6a0 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -2136,6 +2136,26 @@ The guaranteed minimum memory allocation for the guest.
Specifying -1 as a value for these limits is interpreted as unlimited.
+=item B<perf> I<domain> [I<--enable> B<eventName>]
+[I<--disable> B<eventName>]
+
+Get the current perf events setting or enable/disable specific perf
+event for a guest domain.
+
+Perf is a performance analyzing tool in Linux, and it can instrument
+CPU performance counters, tracepoints, kprobes, and uprobes (dynamic
+tracing). Perf supports a list of measurable events, and can measure
+events coming from different sources. For instance, some event are
+pure kernel counters, in this case they are called software events,
+including context-switches, minor-faults, etc.. Now dozens of events
+from different sources can be supported by perf.
+
+Currently only QEMU/KVM supports I<--enable> and I<--disable>.
+B<eventName> is a string listing one or more events, in the format
+of name|name|name. Only "cmt" event is supported presently. CMT is
+a PQos (Platform Qos) feature to monitor the usage of cache by
+applications running on the platform.
+
=item B<blkiotune> I<domain> [I<--weight> B<weight>]
[I<--device-weights> B<device-weights>]
[I<--device-read-iops-sec> B<device-read-iops-sec>]
--
1.9.1