[PATCH v3 7/7] qemu_driver: Add calc_mode for dirtyrate statistics

[Michal Prívozník]

On 1/28/22 08:35, huangy81 at chinatelecom.cn wrote:
> From: Hyman Huang(黄勇) <huangy81 at chinatelecom.cn>
> 
> Add calc_mode for dirtyrate statistics retured by
> virsh domstats --dirtyrate api, also add vcpu dirtyrate
> if dirty-ring mode was used in last measurement.
> 
> Signed-off-by: Hyman Huang(黄勇) <huangy81 at chinatelecom.cn>
> ---
>  src/libvirt-domain.c         |  5 +++++
>  src/qemu/qemu_driver.c       | 14 ++++++++++++
>  src/qemu/qemu_monitor.h      | 10 +++++++++
>  src/qemu/qemu_monitor_json.c | 52 ++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 81 insertions(+)
> 
> diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
> index 4caa740..afc0c1b 100644
> --- a/src/libvirt-domain.c
> +++ b/src/libvirt-domain.c
> @@ -11941,6 +11941,11 @@ virConnectGetDomainCapabilities(virConnectPtr conn,
>   *     "dirtyrate.megabytes_per_second" - the calculated memory dirty rate in
>   *                                        MiB/s as long long. It is produced
>   *                                        only if the calc_status is measured.
> + *     "dirtyrate.calc_mode" - the calculation mode used last measurement as int,
> + *                             which is one of virDomainDirtyRateCalcMode enum.
> + *     "dirtyrate.vcpu.<num>.megabytes_per_second" - the calculated memory dirty
> + *                                                   rate for a virtual cpu as
> + *                                                   unsigned long long.
>   *
>   * Note that entire stats groups or individual stat fields may be missing from
>   * the output in case they are not supported by the given hypervisor, are not
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index 5c2f289..3ef9569 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -18537,6 +18537,20 @@ qemuDomainGetStatsDirtyRate(virQEMUDriver *driver,
>                                    "dirtyrate.megabytes_per_second") < 0)
>          return -1;
>  
> +    if (virTypedParamListAddInt(params, info.mode,
> +                                "dirtyrate.calc_mode") < 0)
> +        return -1;
> +
> +    if (info.mode == VIR_DOMAIN_DIRTYRATE_CALC_MODE_DIRTY_RING) {
> +        int i;
> +        for (i = 0; i < info.nvcpus; i++) {
> +            if (virTypedParamListAddULLong(params, info.rates[i].value,
> +                                           "dirtyrate.vcpu.%d.megabytes_per_second",
> +                                           info.rates[i].index) < 0)
> +            return -1;
> +        }
> +    }
> +
>      return 0;
>  }
>  
> diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h
> index 6d43f23..1e500ce 100644
> --- a/src/qemu/qemu_monitor.h
> +++ b/src/qemu/qemu_monitor.h
> @@ -1556,6 +1556,12 @@ qemuMonitorStartDirtyRateCalc(qemuMonitor *mon,
>                                int seconds,
>                                virDomainDirtyRateCalcMode mode);
>  
> +typedef struct _qemuMonitorDirtyRateVcpu qemuMonitorDirtyRateVcpu;
> +struct _qemuMonitorDirtyRateVcpu {
> +    int index;                  /* virtual cpu index */
> +    unsigned long long value;   /* virtual cpu dirty page rate in MB/s */
> +};
> +
>  typedef struct _qemuMonitorDirtyRateInfo qemuMonitorDirtyRateInfo;
>  struct _qemuMonitorDirtyRateInfo {
>      int status;             /* the status of last dirtyrate calculation,
> @@ -1563,6 +1569,10 @@ struct _qemuMonitorDirtyRateInfo {
>      int calcTime;           /* the period of dirtyrate calculation */
>      long long startTime;    /* the start time of dirtyrate calculation */
>      long long dirtyRate;    /* the dirtyrate in MiB/s */
> +    virDomainDirtyRateCalcMode mode;  /* calculation mode used in
> +                                         last measurement */
> +    size_t nvcpus;  /* number of virtual cpu */
> +    qemuMonitorDirtyRateVcpu *rates; /* array of dirty page rate */
>  };
>  
>  int
> diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
> index 8d62ca7..f088300 100644
> --- a/src/qemu/qemu_monitor_json.c
> +++ b/src/qemu/qemu_monitor_json.c
> @@ -8738,11 +8738,45 @@ VIR_ENUM_IMPL(qemuMonitorDirtyRateStatus,
>                "measured");
>  
>  static int
> +qemuMonitorJSONExtractVcpuDirtyRate(virJSONValue *data,
> +                                    qemuMonitorDirtyRateInfo *info)
> +{
> +    size_t nvcpus;
> +    int i;
> +
> +    nvcpus = virJSONValueArraySize(data);
> +    info->nvcpus = nvcpus;
> +    info->rates = g_new0(qemuMonitorDirtyRateVcpu, nvcpus);
> +
> +    for (i = 0; i < nvcpus; i++) {
> +        virJSONValue *entry = virJSONValueArrayGet(data, i);
> +        if (virJSONValueObjectGetNumberInt(entry, "id",
> +                                           &info->rates[i].index) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                           _("query-dirty-rate reply was missing 'id' data"));
> +            return -1;
> +        }
> +
> +        if (virJSONValueObjectGetNumberUlong(entry, "dirty-rate",
> +                                            &info->rates[i].value) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                           _("query-dirty-rate reply was missing 'dirty-rate' data"));
> +            return -1;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +static int
>  qemuMonitorJSONExtractDirtyRateInfo(virJSONValue *data,
>                                      qemuMonitorDirtyRateInfo *info)
>  {
>      const char *statusstr;
> +    const char *modestr;
>      int status;
> +    int mode;
> +    virJSONValue *rates = NULL;
>  
>      if (!(statusstr = virJSONValueObjectGetString(data, "status"))) {
>          virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> @@ -8779,6 +8813,24 @@ qemuMonitorJSONExtractDirtyRateInfo(virJSONValue *data,
>          return -1;
>      }
>  
> +    info->mode = VIR_DOMAIN_DIRTYRATE_CALC_MODE_PAGE_SAMPLING;

1: ^^^

> +    if ((modestr = virJSONValueObjectGetString(data, "mode"))) {
> +        if ((mode = virDomainDirtyRateCalcModeTypeFromString(modestr)) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR,
> +                       _("Unknown dirty page rate calculation mode: %s"), modestr);
> +            return -1;
> +        }
> +        info->mode = mode;
> +    }

maybe move [1] into an else branch here? Otherwise looking good.

> +
> +    if ((rates = virJSONValueObjectGetArray(data, "vcpu-dirty-rate"))) {
> +        if (qemuMonitorJSONExtractVcpuDirtyRate(rates, info) < 0) {
> +            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("query-dirty-rate parsing 'vcpu-dirty-rate' in failure"));
> +            return -1;
> +        }
> +    }
> +
>      return 0;
>  }
>  

Michal