[libvirt] [PATCHv3 04/10] Implement domainGetCPUStats for lxc driver.

Michal Privoznik mprivozn at redhat.com
Thu Feb 6 11:46:37 UTC 2014


On 03.02.2014 18:44, Thorsten Behrens wrote:
> ---
>
> Notes v3:
>   - moved most of the code out to virCgroupGetPercpuStats, for better
>     testability.
>   - addressed comments from v2 review
>
>   src/libvirt_private.syms |  1 +
>   src/lxc/lxc_driver.c     | 51 ++++++++++++++++++++++++++++++++
>   src/util/vircgroup.c     | 75 ++++++++++++++++++++++++++++++++++++++++++++++++
>   src/util/vircgroup.h     |  7 +++++
>   4 files changed, 134 insertions(+)
>
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index 890d6c7..4a7201e 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -1023,6 +1023,7 @@ virCgroupGetMemorySoftLimit;
>   virCgroupGetMemoryUsage;
>   virCgroupGetMemSwapHardLimit;
>   virCgroupGetMemSwapUsage;
> +virCgroupGetPercpuStats;
>   virCgroupHasController;
>   virCgroupIsolateMount;
>   virCgroupKill;
> diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
> index 02b5cc3..39cd981 100644
> --- a/src/lxc/lxc_driver.c
> +++ b/src/lxc/lxc_driver.c
> @@ -76,6 +76,7 @@
>
>   #define LXC_NB_MEM_PARAM  3
>
> +
>   static int lxcStateInitialize(bool privileged,
>                                 virStateInhibitCallback callback,
>                                 void *opaque);
> @@ -5388,6 +5389,55 @@ cleanup:
>   }
>
>
> +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;

This variable is unnecessary. Although I see you are just copying 
structure we have in the qemu driver.

> +    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 = virCgroupGetPercpuStats(priv->cgroup, params,
> +                                      nparams, start_cpu, ncpus);
> +cleanup:
> +    if (vm)
> +        virObjectUnlock(vm);
> +    return ret;
> +}
> +
> +
>   /* Function Tables */
>   static virDriver lxcDriver = {
>       .no = VIR_DRV_LXC,
> @@ -5466,6 +5516,7 @@ 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 */
> diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
> index 7427a21..268a4ae 100644
> --- a/src/util/vircgroup.c
> +++ b/src/util/vircgroup.c
> @@ -53,11 +53,14 @@
>   #include "virsystemd.h"
>   #include "virtypedparam.h"
>
> +#include "nodeinfo.h"
> +
>   #define CGROUP_MAX_VAL 512
>
>   #define VIR_FROM_THIS VIR_FROM_CGROUP
>
>   #define CGROUP_NB_TOTAL_CPU_STAT_PARAM 3
> +#define CGROUP_NB_PER_CPU_STAT_PARAM   1
>
>   #if defined(__linux__) && defined(HAVE_GETMNTENT_R) && \
>       defined(_DIRENT_HAVE_D_TYPE) && defined(_SC_CLK_TCK)
> @@ -2824,6 +2827,78 @@ virCgroupDenyDevicePath(virCgroupPtr group, const char *path, int perms)
>   }
>
>
> +int
> +virCgroupGetPercpuStats(virCgroupPtr group,
> +                        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;
> +    virTypedParameterPtr ent;
> +    int param_idx;
> +    unsigned long long cpu_time;
> +
> +    /* return the number of supported params */
> +    if (nparams == 0 && ncpus != 0)
> +        return CGROUP_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(group, &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;
> +}
> +
>
>   int
>   virCgroupGetDomainTotalCpuStats(virCgroupPtr group,
> diff --git a/src/util/vircgroup.h b/src/util/vircgroup.h
> index fae4d92..67478f5 100644
> --- a/src/util/vircgroup.h
> +++ b/src/util/vircgroup.h
> @@ -202,6 +202,13 @@ int virCgroupDenyDevicePath(virCgroupPtr group,
>                               int perms);
>
>   int
> +virCgroupGetPercpuStats(virCgroupPtr group,
> +                        virTypedParameterPtr params,
> +                        unsigned int nparams,
> +                        int start_cpu,
> +                        unsigned int ncpus);
> +
> +int
>   virCgroupGetDomainTotalCpuStats(virCgroupPtr group,
>                                   virTypedParameterPtr params,
>                                   int nparams);
>

ACK

Michal




More information about the libvir-list mailing list