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

[Gao feng]

On 01/20/2014 07:12 PM, Thorsten Behrens wrote:
> ---
> 
> 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 */
> 


Looks good to me

ACK

thanks!