Re: [libvirt] [PATCHv2 4/6] Implement domainGetCPUStats for lxc driver.

--- Notes on v2: - elided extra memset and leftover loop var n - api slot comment references 1.2.2 now src/lxc/lxc_driver.c | 128 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c index 8cf8e48..19426f5 100644 --- a/src/lxc/lxc_driver.c +++ b/src/lxc/lxc_driver.c @@ -75,6 +75,8 @@ #define LXC_NB_MEM_PARAM 3 +#define LXC_NB_PER_CPU_STAT_PARAM 1 + static int lxcStateInitialize(bool privileged, virStateInhibitCallback callback, @@ -4775,6 +4777,131 @@ cleanup: } +static int +lxcDomainGetPercpuStats(virDomainObjPtr vm, + virTypedParameterPtr params, + unsigned int nparams, + int start_cpu, + unsigned int ncpus) +{ + int rv = -1; + size_t i; + int id, max_id; + char *pos; + char *buf = NULL; + virLXCDomainObjPrivatePtr priv = vm->privateData; + virTypedParameterPtr ent; + int param_idx; + unsigned long long cpu_time; + + /* TODO: share api contract code with other drivers here */ + + /* return the number of supported params */ + if (nparams == 0 && ncpus != 0) + return LXC_NB_PER_CPU_STAT_PARAM; + + /* To parse account file, we need to know how many cpus are present. */ + max_id = nodeGetCPUCount(); + if (max_id < 0) + return rv; + + if (ncpus == 0) { /* returns max cpu ID */ + rv = max_id; + goto cleanup; + } + + if (start_cpu > max_id) { + virReportError(VIR_ERR_INVALID_ARG, + _("start_cpu %d larger than maximum of %d"), + start_cpu, max_id); + goto cleanup; + } + + /* we get percpu cputime accounting info. */ + if (virCgroupGetCpuacctPercpuUsage(priv->cgroup, &buf)) + goto cleanup; + pos = buf; + + /* return percpu cputime in index 0 */ + param_idx = 0; + + /* number of cpus to compute */ + if (start_cpu >= max_id - ncpus) + id = max_id - 1; + else + id = start_cpu + ncpus - 1; + + for (i = 0; i <= id; i++) { + if (virStrToLong_ull(pos, &pos, 10, &cpu_time) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("cpuacct parse error")); + goto cleanup; + } + if (i < start_cpu) + continue; + ent = &params[(i - start_cpu) * nparams + param_idx]; + if (virTypedParameterAssign(ent, VIR_DOMAIN_CPU_STATS_CPUTIME, + VIR_TYPED_PARAM_ULLONG, cpu_time) < 0) + goto cleanup; + } + + rv = nparams; + +cleanup: + VIR_FREE(buf); + return rv; +} + + +static int +lxcDomainGetCPUStats(virDomainPtr dom, + virTypedParameterPtr params, + unsigned int nparams, + int start_cpu, + unsigned int ncpus, + unsigned int flags) +{ + virDomainObjPtr vm = NULL; + int ret = -1; + bool isActive; + virLXCDomainObjPrivatePtr priv; + + virCheckFlags(VIR_TYPED_PARAM_STRING_OKAY, -1); + + if (!(vm = lxcDomObjFromDomain(dom))) + return ret; + + priv = vm->privateData; + + if (virDomainGetCPUStatsEnsureACL(dom->conn, vm->def) < 0) + goto cleanup; + + isActive = virDomainObjIsActive(vm); + if (!isActive) { + virReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("domain is not running")); + goto cleanup; + } + + if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_CPUACCT)) { + virReportError(VIR_ERR_OPERATION_INVALID, + "%s", _("cgroup CPUACCT controller is not mounted")); + goto cleanup; + } + + if (start_cpu == -1) + ret = virCgroupGetDomainTotalCpuStats(priv->cgroup, + params, nparams); + else + ret = lxcDomainGetPercpuStats(vm, params, nparams, + start_cpu, ncpus); +cleanup: + if (vm) + virObjectUnlock(vm); + return ret; +} + + /* Function Tables */ static virDriver lxcDriver = { .no = VIR_DRV_LXC, @@ -4852,6 +4979,7 @@ static virDriver lxcDriver = { .nodeSuspendForDuration = lxcNodeSuspendForDuration, /* 0.9.8 */ .domainSetMetadata = lxcDomainSetMetadata, /* 1.1.3 */ .domainGetMetadata = lxcDomainGetMetadata, /* 1.1.3 */ + .domainGetCPUStats = lxcDomainGetCPUStats, /* 1.2.2 */ .nodeGetMemoryParameters = lxcNodeGetMemoryParameters, /* 0.10.2 */ .nodeSetMemoryParameters = lxcNodeSetMemoryParameters, /* 0.10.2 */ .domainSendProcessSignal = lxcDomainSendProcessSignal, /* 1.0.1 */