Re: [PATCH v3 1/8] libxl: implement virDomainGetCPUStats

[Joao Martins <joao.m.martins@oracle.com>]

On 11/17/2015 02:59 AM, Jim Fehlig wrote:
> On 11/13/2015 06:14 AM, Joao Martins wrote:
>> Introduce support for domainGetCPUStats API call and consequently
>> allow us to use `virsh cpu-stats`. The latter returns a more brief
>> output than the one provided by`virsh vcpuinfo`.
>>
>> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
>> ---
>> Changes since v1:
>>  - Remove libxl_vcpuinfo_dispose() in favor or using
>>  libxl_vcpuinfo_list_free(), and also removing VIR_FREE call
>>  - Dispose libxl_dominfo after succesfull call to
>>  libxl_domain_info()
>>  - Fixed identation of parameters
>>  - Bump version to 1.2.22
>> ---
>>  src/libxl/libxl_driver.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 110 insertions(+)
>>
>> diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c
>> index fcdcbdb..50f6e34 100644
>> --- a/src/libxl/libxl_driver.c
>> +++ b/src/libxl/libxl_driver.c
>> @@ -73,6 +73,8 @@ VIR_LOG_INIT("libxl.libxl_driver");
>>  #define LIBXL_CONFIG_FORMAT_XM "xen-xm"
>>  #define LIBXL_CONFIG_FORMAT_SEXPR "xen-sxpr"
>>  
>> +#define LIBXL_NB_TOTAL_CPU_STAT_PARAM 1
>> +
>>  #define HYPERVISOR_CAPABILITIES "/proc/xen/capabilities"
>>  #define HYPERVISOR_XENSTORED "/dev/xen/xenstored"
>>  
>> @@ -4641,6 +4643,113 @@ libxlDomainIsUpdated(virDomainPtr dom)
>>  }
>>  
>>  static int
>> +libxlDomainGetTotalCPUStats(libxlDriverPrivatePtr driver,
>> +                            virDomainObjPtr vm,
>> +                            virTypedParameterPtr params,
>> +                            unsigned int nparams)
>> +{
>> +    libxlDriverConfigPtr cfg = libxlDriverConfigGet(driver);
>> +    libxl_dominfo d_info;
>> +    int ret = -1;
>> +
>> +    if (nparams == 0)
>> +        return LIBXL_NB_TOTAL_CPU_STAT_PARAM;
>> +
>> +    if (libxl_domain_info(cfg->ctx, &d_info, vm->def->id) != 0) {
>> +        virReportError(VIR_ERR_INTERNAL_ERROR,
>> +                       _("libxl_domain_info failed for domain '%d'"),
>> +                       vm->def->id);
>> +        return ret;
>> +    }
>> +
>> +    if (virTypedParameterAssign(&params[0], VIR_DOMAIN_CPU_STATS_CPUTIME,
>> +                                VIR_TYPED_PARAM_ULLONG, d_info.cpu_time) < 0)
>> +        nparams = ret;
>> +
>> +    libxl_dominfo_dispose(&d_info);
>> +    return nparams;
> 
> Having a local 'ret' variable but returning nparams was a bit confusing to me.
> I've changed this in my local branch to
> 
>     if (virTypedParameterAssign(&params[0], VIR_DOMAIN_CPU_STATS_CPUTIME,
>                                 VIR_TYPED_PARAM_ULLONG, d_info.cpu_time) < 0)
>         goto cleanup;
> 
>     ret = nparams;
> 
>  cleanup:
>     libxl_dominfo_dispose(&d_info);
>     return ret;
> 
OK. I solely did it to avoid the additional goto, but wasn't so clear in the end.

>> +}
>> +
>> +static int
>> +libxlDomainGetPerCPUStats(libxlDriverPrivatePtr driver,
>> +                          virDomainObjPtr vm,
>> +                          virTypedParameterPtr params,
>> +                          unsigned int nparams,
>> +                          int start_cpu,
>> +                          unsigned int ncpus)
>> +{
>> +    libxl_vcpuinfo *vcpuinfo;
>> +    int maxcpu, hostcpus;
>> +    size_t i;
>> +    libxlDriverConfigPtr cfg = libxlDriverConfigGet(driver);
>> +    int ret = -1;
>> +
>> +    if (nparams == 0 && ncpus != 0)
>> +        return LIBXL_NB_TOTAL_CPU_STAT_PARAM;
>> +    else if (nparams == 0)
>> +        return vm->def->maxvcpus;
>> +
>> +    if ((vcpuinfo = libxl_list_vcpu(cfg->ctx, vm->def->id, &maxcpu,
>> +                                    &hostcpus)) == NULL) {
>> +        virReportError(VIR_ERR_INTERNAL_ERROR,
>> +                       _("Failed to list vcpus for domain '%d' with libxenlight"),
>> +                       vm->def->id);
>> +        return ret;
>> +    }
>> +
>> +    for (i = start_cpu; i < maxcpu && i < ncpus; ++i) {
>> +        if (virTypedParameterAssign(&params[(i-start_cpu)],
>> +                                    VIR_DOMAIN_CPU_STATS_CPUTIME,
>> +                                    VIR_TYPED_PARAM_ULLONG,
>> +                                    vcpuinfo[i].vcpu_time) < 0)
>> +            goto cleanup;
>> +    }
>> +    ret = nparams;
>> +
>> + cleanup:
>> +    libxl_vcpuinfo_list_free(vcpuinfo, maxcpu);
>> +    return ret;
>> +}
>> +
>> +static int
>> +libxlDomainGetCPUStats(virDomainPtr dom,
>> +                       virTypedParameterPtr params,
>> +                       unsigned int nparams,
>> +                       int start_cpu,
>> +                       unsigned int ncpus,
>> +                       unsigned int flags)
>> +{
>> +    libxlDriverPrivatePtr driver = dom->conn->privateData;
>> +    virDomainObjPtr vm = NULL;
>> +    int ret = -1;
>> +
>> +    virCheckFlags(VIR_TYPED_PARAM_STRING_OKAY, -1);
>> +
>> +    if (!(vm = libxlDomObjFromDomain(dom)))
>> +        goto cleanup;
>> +
>> +    if (virDomainGetCPUStatsEnsureACL(dom->conn, vm->def) < 0)
>> +        goto cleanup;
>> +
>> +    if (!virDomainObjIsActive(vm)) {
>> +        virReportError(VIR_ERR_OPERATION_INVALID,
>> +                       "%s", _("domain is not running"));
>> +        goto cleanup;
>> +    }
>> +
>> +    if (start_cpu == -1)
>> +        ret = libxlDomainGetTotalCPUStats(driver, vm, params, nparams);
>> +    else
>> +        ret = libxlDomainGetPerCPUStats(driver, vm, params, nparams,
>> +                                          start_cpu, ncpus);
>> +
>> + cleanup:
>> +    if (vm)
>> +        virObjectUnlock(vm);
>> +    return ret;
>> +}
>> +
>> +static int
>>  libxlConnectDomainEventRegisterAny(virConnectPtr conn, virDomainPtr dom, int eventID,
>>                                     virConnectDomainEventGenericCallback callback,
>>                                     void *opaque, virFreeCallback freecb)
>> @@ -5233,6 +5342,7 @@ static virHypervisorDriver libxlHypervisorDriver = {
>>  #endif
>>      .nodeGetFreeMemory = libxlNodeGetFreeMemory, /* 0.9.0 */
>>      .nodeGetCellsFreeMemory = libxlNodeGetCellsFreeMemory, /* 1.1.1 */
>> +    .domainGetCPUStats = libxlDomainGetCPUStats, /* 1.2.22 */
> 
> ACK with the above nit fixed. I'll push this one too after verifying whether
> next release is 1.2.22 or 1.3.0.
Great, Thanks! :D

Cheers,
Joao
> 
> Regards,
> Jim
>