1:53 a.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 | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++
tools/virsh.pod | 18 ++++++++
2 files changed, 143 insertions(+)
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index b7e7606..a47ef9f 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -8888,6 +8888,125 @@ 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 = "cmt",
+ .type = VSH_OT_INT,
+ .help = N_("CMT event, as integer (default 0, disable)")
+ },
+ {.name = NULL}
+};
+
+static int
+virshPerfGetEventEnabled(vshControl *ctl, const vshCmd *cmd,
+ const char *name, bool *value)
+{
+ int ret, tmp;
+ const char *str;
+ char *end;
+
+ ret = vshCommandOptString(ctl, cmd, name, &str);
+ if (ret <= 0)
+ return ret;
+ if (virStrToLong_i(str, &end, 0, &tmp) < 0)
+ return -1;
+ if (tmp == 1) {
+ *value = true;
+ ret = 1;
+ } else if (tmp == 0) {
+ *value = false;
+ ret = 1;
+ } else {
+ ret = -1;
+ }
+
+ return ret;
+}
+
+static bool
+cmdPerf(vshControl *ctl, const vshCmd *cmd)
+{
+ virDomainPtr dom;
+ bool tmpVal;
+ int nparams = 0;
+ int maxparams = 0;
+ int rc;
+ size_t i;
+ virTypedParameterPtr params = NULL;
+ bool ret = false;
+
+ if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
+ return false;
+
+#define PARSE_PERF_PARAM(NAME, FIELD) \
+ if ((rc = virshPerfGetEventEnabled(ctl, cmd, NAME, &tmpVal)) < 0) { \
+ vshError(ctl, _("Unable to parse boolean parameter %s"), NAME); \
+ goto cleanup; \
+ } \
+ if (rc == 1) { \
+ if (virTypedParamsAddBoolean(¶ms, &nparams, &maxparams,
\
+ FIELD, tmpVal) < 0) \
+ goto save_error; \
+ } \
+
+
+ PARSE_PERF_PARAM("cmt", VIR_PERF_PARAM_CMT);
+
+#undef PARSE_PERF_PARAM
+
+ 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;
+
+ save_error:
+ vshSaveLibvirtError();
+ error:
+ vshError(ctl, "%s", _("Unable to enable/disable perf events"));
+ goto cleanup;
+}
+
+
+/*
* "numatune" command
*/
static const vshCmdInfo info_numatune[] = {
@@ -13406,6 +13525,12 @@ 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 21ae4a3..6ddf360 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -2113,6 +2113,24 @@ 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<--cmt> B<enable-disable>]
+
+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<--cmt>. CMT is a PQos (Platform Qos)
+feature to monitor the usage of cache by applications running on the
+platform. B<enable-disable> may be 0 or 1. 0 means cmt perf event will
+be disabled, and 1 means cmt perf event will be enabled.
+
=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