[libvirt] [PATCH 1/1] perf: add support to perf event for MBM

Qiaowei Ren qiaowei.ren at intel.com
Thu May 12 06:55:16 UTC 2016


Some Intel processor families (e.g. the Intel Xeon processor E5 v3
family) introduced some RDT (Resource Director Technology) features
to monitor or control shared resource. Among these features, MBM
(Memory Bandwidth Monitoring), which is build on the CMT (Cache
Monitoring Technology) infrastructure, provides OS/VMM a way to
monitor bandwidth from one level of cache to another.

With current perf framework, this patch adds support to perf event
for MBM.

Signed-off-by: Qiaowei Ren <qiaowei.ren at intel.com>
---
 include/libvirt/libvirt-domain.h | 18 ++++++++++++
 src/qemu/qemu_driver.c           | 35 +++++++++++++++++++----
 src/util/virperf.c               | 60 ++++++++++++++++++++++++----------------
 src/util/virperf.h               |  2 ++
 4 files changed, 85 insertions(+), 30 deletions(-)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 160f20f..e4594f0 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -1904,6 +1904,24 @@ void virDomainStatsRecordListFree(virDomainStatsRecordPtr *stats);
  */
 # define VIR_PERF_PARAM_CMT "cmt"
 
+/**
+ * VIR_PERF_PARAM_MBMT:
+ *
+ * Macro for typed parameter name that represents MBMT perf event
+ * which can be used to monitor total system bandwidth (bytes/s)
+ * from one level of cache to another.
+ */
+# define VIR_PERF_PARAM_MBMT "mbmt"
+
+/**
+ * VIR_PERF_PARAM_MBML:
+ *
+ * Macro for typed parameter name that represents MBML perf event
+ * which can be used to monitor the amount of data (bytes/s) sent
+ * through the memory controller on the socket.
+ */
+# define VIR_PERF_PARAM_MBML "mbml"
+
 int virDomainGetPerfEvents(virDomainPtr dom,
                            virTypedParameterPtr *params,
                            int *nparams,
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index c4c4968..a3bd7ec 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -10051,6 +10051,8 @@ qemuDomainSetPerfEvents(virDomainPtr dom,
 
     if (virTypedParamsValidate(params, nparams,
                                VIR_PERF_PARAM_CMT, VIR_TYPED_PARAM_BOOLEAN,
+                               VIR_PERF_PARAM_MBMT, VIR_TYPED_PARAM_BOOLEAN,
+                               VIR_PERF_PARAM_MBML, VIR_TYPED_PARAM_BOOLEAN,
                                NULL) < 0)
         return -1;
 
@@ -19495,20 +19497,38 @@ qemuDomainGetStatsBlock(virQEMUDriverPtr driver,
 #undef QEMU_ADD_COUNT_PARAM
 
 static int
-qemuDomainGetStatsPerfCmt(virPerfPtr perf,
+qemuDomainGetStatsPerfRdt(virPerfPtr perf,
+                          virPerfEventType type,
                           virDomainStatsRecordPtr record,
                           int *maxparams)
 {
-    uint64_t cache = 0;
+    uint64_t value = 0;
 
-    if (virPerfReadEvent(perf, VIR_PERF_EVENT_CMT, &cache) < 0)
+    if (virPerfReadEvent(perf, type, &value) < 0)
         return -1;
 
-    if (virTypedParamsAddULLong(&record->params,
+    if (type == VIR_PERF_EVENT_CMT &&
+        virTypedParamsAddULLong(&record->params,
                                 &record->nparams,
                                 maxparams,
                                 "perf.cache",
-                                cache) < 0)
+                                value) < 0)
+        return -1;
+
+    if (type == VIR_PERF_EVENT_MBMT &&
+        virTypedParamsAddULLong(&record->params,
+                                &record->nparams,
+                                maxparams,
+                                "perf.total_bytes",
+                                value) < 0)
+        return -1;
+
+    if (type == VIR_PERF_EVENT_MBML &&
+        virTypedParamsAddULLong(&record->params,
+                                &record->nparams,
+                                maxparams,
+                                "perf.local_bytes",
+                                value) < 0)
         return -1;
 
     return 0;
@@ -19531,7 +19551,10 @@ qemuDomainGetStatsPerf(virQEMUDriverPtr driver ATTRIBUTE_UNUSED,
 
         switch (i) {
         case VIR_PERF_EVENT_CMT:
-            if (qemuDomainGetStatsPerfCmt(priv->perf, record, maxparams) < 0)
+        case VIR_PERF_EVENT_MBMT:
+        case VIR_PERF_EVENT_MBML:
+            if (qemuDomainGetStatsPerfRdt(priv->perf, i,
+                                          record, maxparams) < 0)
                 goto cleanup;
             break;
         }
diff --git a/src/util/virperf.c b/src/util/virperf.c
index bd65587..826d36a 100644
--- a/src/util/virperf.c
+++ b/src/util/virperf.c
@@ -38,7 +38,7 @@ VIR_LOG_INIT("util.perf");
 #define VIR_FROM_THIS VIR_FROM_PERF
 
 VIR_ENUM_IMPL(virPerfEvent, VIR_PERF_EVENT_LAST,
-              "cmt");
+              "cmt", "mbmt", "mbml");
 
 struct virPerfEvent {
     int type;
@@ -110,10 +110,10 @@ virPerfGetEvent(virPerfPtr perf,
 }
 
 static int
-virPerfCmtEnable(virPerfEventPtr event,
+virPerfRdtEnable(virPerfEventPtr event,
                  pid_t pid)
 {
-    struct perf_event_attr cmt_attr;
+    struct perf_event_attr rdt_attr;
     char *buf = NULL;
     char *tmp = NULL;
     unsigned int event_type, scale;
@@ -127,32 +127,42 @@ virPerfCmtEnable(virPerfEventPtr event,
 
     if (virStrToLong_ui(buf, NULL, 10, &event_type) < 0) {
         virReportSystemError(errno, "%s",
-                             _("failed to get cmt event type"));
+                             _("failed to get rdt event type"));
         goto error;
     }
     VIR_FREE(buf);
 
-    if (virFileReadAll("/sys/devices/intel_cqm/events/llc_occupancy.scale",
-                       10, &buf) < 0)
-        goto error;
+    memset(&rdt_attr, 0, sizeof(rdt_attr));
+    rdt_attr.size = sizeof(rdt_attr);
+    rdt_attr.type = event_type;
+    rdt_attr.inherit = 1;
+    rdt_attr.disabled = 1;
+    rdt_attr.enable_on_exec = 0;
 
-    if (virStrToLong_ui(buf, NULL, 10, &scale) < 0) {
-        virReportSystemError(errno, "%s",
-                             _("failed to get cmt scaling factor"));
-        goto error;
+    switch (event->type) {
+    case VIR_PERF_EVENT_CMT:
+        if (virFileReadAll("/sys/devices/intel_cqm/events/llc_occupancy.scale",
+                           10, &buf) < 0)
+            goto error;
+
+        if (virStrToLong_ui(buf, NULL, 10, &scale) < 0) {
+            virReportSystemError(errno, "%s",
+                                 _("failed to get cmt scaling factor"));
+            goto error;
+        }
+        event->efields.cmt.scale = scale;
+
+        rdt_attr.config = 1;
+        break;
+    case VIR_PERF_EVENT_MBMT:
+        rdt_attr.config = 2;
+        break;
+    case VIR_PERF_EVENT_MBML:
+        rdt_attr.config = 3;
+        break;
     }
 
-    event->efields.cmt.scale = scale;
-
-    memset(&cmt_attr, 0, sizeof(cmt_attr));
-    cmt_attr.size = sizeof(cmt_attr);
-    cmt_attr.type = event_type;
-    cmt_attr.config = 1;
-    cmt_attr.inherit = 1;
-    cmt_attr.disabled = 1;
-    cmt_attr.enable_on_exec = 0;
-
-    event->fd = syscall(__NR_perf_event_open, &cmt_attr, pid, -1, -1, 0);
+    event->fd = syscall(__NR_perf_event_open, &rdt_attr, pid, -1, -1, 0);
     if (event->fd < 0) {
         virReportSystemError(errno,
                              _("Unable to open perf type=%d for pid=%d"),
@@ -162,7 +172,7 @@ virPerfCmtEnable(virPerfEventPtr event,
 
     if (ioctl(event->fd, PERF_EVENT_IOC_ENABLE) < 0) {
         virReportSystemError(errno, "%s",
-                             _("Unable to enable perf event for CMT"));
+                             _("Unable to enable perf event for RDT"));
         goto error;
     }
 
@@ -186,7 +196,9 @@ virPerfEventEnable(virPerfPtr perf,
 
     switch (type) {
     case VIR_PERF_EVENT_CMT:
-        if (virPerfCmtEnable(event, pid) < 0)
+    case VIR_PERF_EVENT_MBMT:
+    case VIR_PERF_EVENT_MBML:
+        if (virPerfRdtEnable(event, pid) < 0)
             return -1;
         break;
     case VIR_PERF_EVENT_LAST:
diff --git a/src/util/virperf.h b/src/util/virperf.h
index 8ec8753..769e85a 100644
--- a/src/util/virperf.h
+++ b/src/util/virperf.h
@@ -26,6 +26,8 @@
 
 typedef enum {
     VIR_PERF_EVENT_CMT,
+    VIR_PERF_EVENT_MBMT,
+    VIR_PERF_EVENT_MBML,
 
     VIR_PERF_EVENT_LAST
 } virPerfEventType;
-- 
1.9.1




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