[libvirt] [PATCH V4 4/5] qemu driver for virDomainGetCPUStats()
KAMEZAWA Hiroyuki
kamezawa.hiroyu at jp.fujitsu.com
Sat Jan 28 06:25:26 UTC 2012
qemu driver for virDomainGetCPUstats using cpuacct cgroup.
* Now, only "cpu_time" is supported.
* cpuacct cgroup is used for providing percpu cputime information.
* include/libvirt/libvirt.h.in - defines VIR_DOMAIN_CPU_STATS_CPUTIME
* src/qemu/qemu.conf - take care of cpuacct cgroup.
* src/qemu/qemu_conf.c - take care of cpuacct cgroup.
* src/qemu/qemu_driver.c - added an interface
* src/util/cgroup.c/h - added interface for getting percpu cputime
---
include/libvirt/libvirt.h.in | 6 ++
src/qemu/qemu.conf | 3 +-
src/qemu/qemu_conf.c | 3 +-
src/qemu/qemu_driver.c | 157 ++++++++++++++++++++++++++++++++++++++++++
src/util/cgroup.c | 6 ++
src/util/cgroup.h | 1 +
6 files changed, 174 insertions(+), 2 deletions(-)
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index e8b5116..2020059 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -3797,6 +3797,12 @@ int virConnectSetKeepAlive(virConnectPtr conn,
int interval,
unsigned int count);
+/**
+ * VIR_DOMAIN_CPU_STATS_CPUTIME:
+ * cpu usage in nanosecond, as a ullong
+ */
+#define VIR_DOMAIN_CPU_STATS_CPUTIME "cpu_time"
+
int virDomainGetCPUStats(virDomainPtr domain,
virTypedParameterPtr params,
unsigned int nparams,
diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf
index 4ec5e6c..181d853 100644
--- a/src/qemu/qemu.conf
+++ b/src/qemu/qemu.conf
@@ -158,6 +158,7 @@
# - 'memory' - use for memory tunables
# - 'blkio' - use for block devices I/O tunables
# - 'cpuset' - use for CPUs and memory nodes
+# - cpuacct - use for CPUs statistics.
#
# NB, even if configured here, they won't be used unless
# the administrator has mounted cgroups, e.g.:
@@ -169,7 +170,7 @@
# can be mounted in different locations. libvirt will detect
# where they are located.
#
-# cgroup_controllers = [ "cpu", "devices", "memory", "blkio", "cpuset" ]
+# cgroup_controllers = [ "cpu", "devices", "memory", "blkio", "cpuset", "cpuacct" ]
# This is the basic set of devices allowed / required by
# all virtual machines.
diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index bc0a646..4775638 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -307,7 +307,8 @@ int qemudLoadDriverConfig(struct qemud_driver *driver,
(1 << VIR_CGROUP_CONTROLLER_DEVICES) |
(1 << VIR_CGROUP_CONTROLLER_MEMORY) |
(1 << VIR_CGROUP_CONTROLLER_BLKIO) |
- (1 << VIR_CGROUP_CONTROLLER_CPUSET);
+ (1 << VIR_CGROUP_CONTROLLER_CPUSET) |
+ (1 << VIR_CGROUP_CONTROLLER_CPUACCT);
}
for (i = 0 ; i < VIR_CGROUP_CONTROLLER_LAST ; i++) {
if (driver->cgroupControllers & (1 << i)) {
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index ab69dca..52f9ebd 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -11740,6 +11740,162 @@ cleanup:
return ret;
}
+
+/* qemuDomainGetCPUStats() with start_cpu == -1 */
+static int qemuDomainGetTotalcpuStats(virDomainPtr domain ATTRIBUTE_UNUSED,
+ virCgroupPtr group,
+ virTypedParameterPtr params,
+ int nparams,
+ unsigned int flags)
+{
+ unsigned long long cpu_time;
+ int param_idx = 0;
+ int ret;
+
+ virCheckFlags(0, -1);
+
+ if (nparams == 0) /* return supprted number of params */
+ return 1;
+ /* entry 0 is cputime */
+ ret = virCgroupGetCpuacctUsage(group, &cpu_time);
+ if (ret < 0) {
+ virReportSystemError(-ret, "%s", _("unable to get cpu account"));
+ return -1;
+ }
+
+ virTypedParameterAssign(¶ms[param_idx], VIR_DOMAIN_CPU_STATS_CPUTIME,
+ VIR_TYPED_PARAM_ULLONG, cpu_time);
+ return param_idx + 1;
+}
+
+static int qemuDomainGetPercpuStats(virDomainPtr domain,
+ virCgroupPtr group,
+ virTypedParameterPtr params,
+ unsigned int nparams,
+ int start_cpu,
+ unsigned int ncpus,
+ unsigned int flags)
+{
+ virBitmapPtr map = NULL;
+ int rv = -1;
+ int i, max_id;
+ char *pos;
+ char *buf = NULL;
+ virTypedParameterPtr ent;
+ int param_idx;
+
+ virCheckFlags(0, -1);
+ /* return the number of supported params ? */
+ if (nparams == 0 && ncpus != 0)
+ return 1; /* only cpu_time is supported */
+
+ /* return percpu cputime in index 0 */
+ param_idx = 0;
+ /* to parse account file, we need "present" cpu map */
+ map = nodeGetCPUmap(domain->conn, &max_id, "present");
+ if (!map)
+ return rv;
+
+ if (ncpus == 0) { /* returns max cpu ID */
+ rv = max_id;
+ goto cleanup;
+ }
+ /* we get percpu cputime accoutning info. */
+ if (virCgroupGetCpuacctPercpuUsage(group, &buf))
+ goto cleanup;
+ pos = buf;
+
+ if (max_id > start_cpu + ncpus - 1)
+ max_id = start_cpu + ncpus - 1;
+
+ for (i = 0; i <= max_id; i++) {
+ bool exist;
+ unsigned long long cpu_time;
+
+ if (virBitmapGetBit(map, i, &exist) < 0) {
+ qemuReportError(VIR_ERR_INTERNAL_ERROR, _("bitmap parse error"));
+ goto cleanup;
+ }
+ if (!exist)
+ continue;
+ if (virStrToLong_ull(pos, &pos, 10, &cpu_time) < 0) {
+ qemuReportError(VIR_ERR_INTERNAL_ERROR,
+ _("cpuacct parse error"));
+ goto cleanup;
+ }
+ if (i < start_cpu)
+ continue;
+ ent = ¶ms[ (i - start_cpu) * nparams + param_idx];
+ virTypedParameterAssign(ent, VIR_DOMAIN_CPU_STATS_CPUTIME,
+ VIR_TYPED_PARAM_ULLONG, cpu_time);
+ }
+ rv = param_idx + 1;
+cleanup:
+ VIR_FREE(buf);
+ virBitmapFree(map);
+ return rv;
+}
+
+
+static int
+qemuDomainGetCPUStats(virDomainPtr domain,
+ virTypedParameterPtr params,
+ unsigned int nparams,
+ int start_cpu,
+ unsigned int ncpus,
+ unsigned int flags)
+{
+ struct qemud_driver *driver = domain->conn->privateData;
+ virCgroupPtr group = NULL;
+ virDomainObjPtr vm = NULL;
+ int ret = -1;
+ bool isActive;
+
+ virCheckFlags(0, -1);
+
+ qemuDriverLock(driver);
+
+ vm = virDomainFindByUUID(&driver->domains, domain->uuid);
+ if (vm == NULL) {
+ qemuReportError(VIR_ERR_INTERNAL_ERROR,
+ _("No such domain %s"), domain->uuid);
+ goto cleanup;
+ }
+
+ isActive = virDomainObjIsActive(vm);
+ if (!isActive) {
+ qemuReportError(VIR_ERR_OPERATION_INVALID, "%s",
+ _("domain is not running"));
+ goto cleanup;
+ }
+
+ if (!qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPUACCT)) {
+ qemuReportError(VIR_ERR_OPERATION_INVALID,
+ "%s", _("cgroup CPUACCT controller is not mounted"));
+ goto cleanup;
+ }
+
+ if (virCgroupForDomain(driver->cgroup, vm->def->name, &group, 0) != 0) {
+ qemuReportError(VIR_ERR_INTERNAL_ERROR,
+ _("cannot find cgroup for domain %s"), vm->def->name);
+ goto cleanup;
+ }
+
+ if (nparams == 0 && ncpus == 0) /* returns max cpu id */
+ ret = qemuDomainGetPercpuStats(domain, group, NULL, 0, 0, 0, flags);
+ else if (start_cpu == -1) /* get total */
+ ret = qemuDomainGetTotalcpuStats(domain, group, params, nparams, flags);
+ else
+ ret = qemuDomainGetPercpuStats(domain, group, params, nparams,
+ start_cpu, ncpus ,flags);
+cleanup:
+ virCgroupFree(&group);
+ if (vm)
+ virDomainObjUnlock(vm);
+ qemuDriverUnlock(driver);
+ return ret;
+}
+
static virDriver qemuDriver = {
.no = VIR_DRV_QEMU,
.name = "QEMU",
@@ -11893,6 +12049,7 @@ static virDriver qemuDriver = {
.domainGetNumaParameters = qemuDomainGetNumaParameters, /* 0.9.9 */
.domainGetInterfaceParameters = qemuDomainGetInterfaceParameters, /* 0.9.9 */
.domainSetInterfaceParameters = qemuDomainSetInterfaceParameters, /* 0.9.9 */
+ .domainGetCPUStats = qemuDomainGetCPUStats, /* 0.9.10 */
};
diff --git a/src/util/cgroup.c b/src/util/cgroup.c
index 15b870d..2d34c50 100644
--- a/src/util/cgroup.c
+++ b/src/util/cgroup.c
@@ -1555,6 +1555,12 @@ int virCgroupGetCpuacctUsage(virCgroupPtr group, unsigned long long *usage)
"cpuacct.usage", usage);
}
+int virCgroupGetCpuacctPercpuUsage(virCgroupPtr group, char **usage)
+{
+ return virCgroupGetValueStr(group, VIR_CGROUP_CONTROLLER_CPUACCT,
+ "cpuacct.usage_percpu", usage);
+}
+
int virCgroupSetFreezerState(virCgroupPtr group, const char *state)
{
return virCgroupSetValueStr(group,
diff --git a/src/util/cgroup.h b/src/util/cgroup.h
index 8d75735..b4e0f37 100644
--- a/src/util/cgroup.h
+++ b/src/util/cgroup.h
@@ -115,6 +115,7 @@ int virCgroupSetCpuCfsQuota(virCgroupPtr group, long long cfs_quota);
int virCgroupGetCpuCfsQuota(virCgroupPtr group, long long *cfs_quota);
int virCgroupGetCpuacctUsage(virCgroupPtr group, unsigned long long *usage);
+int virCgroupGetCpuacctPercpuUsage(virCgroupPtr group, char **usage);
int virCgroupSetFreezerState(virCgroupPtr group, const char *state);
int virCgroupGetFreezerState(virCgroupPtr group, char **state);
--
1.7.4.1
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