[libvirt] [PATCH v3 01/11] qemu: Add support for DUMP_COMPLETED event

[Jiri Denemark]

On Mon, Jan 29, 2018 at 11:31:59 -0500, John Ferlan wrote:
> The event will be fired when the domain memory only dump completes.
> 
> Alloc a return buffer to store/pass along the dump statistics that
> will be eventually shared by a query-dump command.
> 
> Signed-off-by: John Ferlan <jferlan at redhat.com>
> ---
>  src/qemu/qemu_monitor.c      | 29 ++++++++++++++++++++
>  src/qemu/qemu_monitor.h      | 31 +++++++++++++++++++++
>  src/qemu/qemu_monitor_json.c | 65 ++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 125 insertions(+)
> 
> diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
> index fc146bdbf..23153967c 100644
> --- a/src/qemu/qemu_monitor.c
> +++ b/src/qemu/qemu_monitor.c
> @@ -210,6 +210,10 @@ VIR_ENUM_IMPL(qemuMonitorBlockIOStatus,
>                QEMU_MONITOR_BLOCK_IO_STATUS_LAST,
>                "ok", "failed", "nospace")
>  
> +VIR_ENUM_IMPL(qemuMonitorDumpStatus,
> +              QEMU_MONITOR_DUMP_STATUS_LAST,
> +              "none", "active", "completed", "failed")
> +
>  char *
>  qemuMonitorEscapeArg(const char *in)
>  {
> @@ -1667,6 +1671,21 @@ qemuMonitorEmitBlockThreshold(qemuMonitorPtr mon,
>  
>  
>  int
> +qemuMonitorEmitDumpCompleted(qemuMonitorPtr mon,
> +                             qemuMonitorDumpStatsPtr stats,
> +                             const char *error)
> +{
> +    int ret = -1;
> +
> +    VIR_DEBUG("mon=%p", mon);
> +
> +    QEMU_MONITOR_CALLBACK(mon, ret, domainDumpCompleted, mon->vm, stats, error);
> +
> +    return ret;
> +}
> +
> +
> +int
>  qemuMonitorSetCapabilities(qemuMonitorPtr mon)
>  {
>      QEMU_CHECK_MONITOR(mon);
> @@ -4359,3 +4378,13 @@ qemuMonitorSetWatchdogAction(qemuMonitorPtr mon,
>  
>      return qemuMonitorJSONSetWatchdogAction(mon, action);
>  }
> +
> +
> +void
> +qemuMonitorEventDumpStatsFree(qemuMonitorDumpStatsPtr stats)
> +{
> +    if (!stats)
> +        return;
> +
> +    VIR_FREE(stats);
> +}

The caller can just use VIR_FREE() directly and benefit from it
automatically resetting the pointer to NULL. Anyway, I don't think we
need to ever free this structure.

> diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h
> index 67b785e60..37f335e9f 100644
> --- a/src/qemu/qemu_monitor.h
> +++ b/src/qemu/qemu_monitor.h
> @@ -246,6 +246,30 @@ typedef int (*qemuMonitorDomainBlockThresholdCallback)(qemuMonitorPtr mon,
>                                                         unsigned long long excess,
>                                                         void *opaque);
>  
> +typedef enum {
> +    QEMU_MONITOR_DUMP_STATUS_NONE,
> +    QEMU_MONITOR_DUMP_STATUS_ACTIVE,
> +    QEMU_MONITOR_DUMP_STATUS_COMPLETED,
> +    QEMU_MONITOR_DUMP_STATUS_FAILED,
> +
> +    QEMU_MONITOR_DUMP_STATUS_LAST,
> +} qemuMonitorDumpStatus;
> +
> +VIR_ENUM_DECL(qemuMonitorDumpStatus)
> +
> +typedef struct _qemuMonitorDumpStats qemuMonitorDumpStats;
> +typedef qemuMonitorDumpStats *qemuMonitorDumpStatsPtr;
> +struct _qemuMonitorDumpStats {
> +    int status; /* qemuMonitorDumpStatus */
> +    unsigned long long completed; /* bytes written */
> +    unsigned long long total; /* total bytes to be written */
> +};
> +
> +typedef int (*qemuMonitorDomainDumpCompletedCallback)(qemuMonitorPtr mon,
> +                                                      virDomainObjPtr vm,
> +                                                      qemuMonitorDumpStatsPtr stats,
> +                                                      const char *error,
> +                                                      void *opaque);
>  
>  typedef struct _qemuMonitorCallbacks qemuMonitorCallbacks;
>  typedef qemuMonitorCallbacks *qemuMonitorCallbacksPtr;
> @@ -279,6 +303,7 @@ struct _qemuMonitorCallbacks {
>      qemuMonitorDomainMigrationPassCallback domainMigrationPass;
>      qemuMonitorDomainAcpiOstInfoCallback domainAcpiOstInfo;
>      qemuMonitorDomainBlockThresholdCallback domainBlockThreshold;
> +    qemuMonitorDomainDumpCompletedCallback domainDumpCompleted;
>  };
>  
>  char *qemuMonitorEscapeArg(const char *in);
> @@ -408,6 +433,10 @@ int qemuMonitorEmitBlockThreshold(qemuMonitorPtr mon,
>                                    unsigned long long threshold,
>                                    unsigned long long excess);
>  
> +int qemuMonitorEmitDumpCompleted(qemuMonitorPtr mon,
> +                                 qemuMonitorDumpStatsPtr stats,
> +                                 const char *error);
> +
>  int qemuMonitorStartCPUs(qemuMonitorPtr mon,
>                           virConnectPtr conn);
>  int qemuMonitorStopCPUs(qemuMonitorPtr mon);
> @@ -1146,4 +1175,6 @@ virJSONValuePtr qemuMonitorQueryNamedBlockNodes(qemuMonitorPtr mon);
>  
>  int qemuMonitorSetWatchdogAction(qemuMonitorPtr mon,
>                                   const char *action);
> +
> +void qemuMonitorEventDumpStatsFree(qemuMonitorDumpStatsPtr stats);
>  #endif /* QEMU_MONITOR_H */
> diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
> index 5ddd85575..a8cb8ce6b 100644
> --- a/src/qemu/qemu_monitor_json.c
> +++ b/src/qemu/qemu_monitor_json.c
> @@ -90,6 +90,7 @@ static void qemuMonitorJSONHandleMigrationStatus(qemuMonitorPtr mon, virJSONValu
>  static void qemuMonitorJSONHandleMigrationPass(qemuMonitorPtr mon, virJSONValuePtr data);
>  static void qemuMonitorJSONHandleAcpiOstInfo(qemuMonitorPtr mon, virJSONValuePtr data);
>  static void qemuMonitorJSONHandleBlockThreshold(qemuMonitorPtr mon, virJSONValuePtr data);
> +static void qemuMonitorJSONHandleDumpCompleted(qemuMonitorPtr mon, virJSONValuePtr data);
>  
>  typedef struct {
>      const char *type;
> @@ -106,6 +107,7 @@ static qemuEventHandler eventHandlers[] = {
>      { "BLOCK_WRITE_THRESHOLD", qemuMonitorJSONHandleBlockThreshold, },
>      { "DEVICE_DELETED", qemuMonitorJSONHandleDeviceDeleted, },
>      { "DEVICE_TRAY_MOVED", qemuMonitorJSONHandleTrayChange, },
> +    { "DUMP_COMPLETED", qemuMonitorJSONHandleDumpCompleted, },
>      { "GUEST_PANICKED", qemuMonitorJSONHandleGuestPanic, },
>      { "MIGRATION", qemuMonitorJSONHandleMigrationStatus, },
>      { "MIGRATION_PASS", qemuMonitorJSONHandleMigrationPass, },
> @@ -1143,6 +1145,69 @@ qemuMonitorJSONHandleBlockThreshold(qemuMonitorPtr mon, virJSONValuePtr data)
>  }
>  
>  
> +static qemuMonitorDumpStatsPtr
> +qemuMonitorJSONExtractDumpStats(virJSONValuePtr result)
> +{
> +    qemuMonitorDumpStatsPtr ret;
> +    const char *statusstr;
> +
> +    if (VIR_ALLOC(ret) < 0)
> +        return NULL;

I think it would be better if this just worked on an existing reference
to qemuMonitorDumpStats passed as an additional argument.

> +
> +    if (!(statusstr = virJSONValueObjectGetString(result, "status"))) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("incomplete result, failed to get status"));
> +        goto error;
> +    }
> +
> +    ret->status = qemuMonitorDumpStatusTypeFromString(statusstr);
> +    if (ret->status < 0) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR,
> +                       _("incomplete result, unknown status string '%s'"),
> +                       statusstr);
> +        goto error;
> +    }
> +
> +    if (virJSONValueObjectGetNumberUlong(result, "completed", &ret->completed) < 0) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("incomplete result, failed to get completed"));
> +        goto error;
> +    }
> +
> +    if (virJSONValueObjectGetNumberUlong(result, "total", &ret->total) < 0) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("incomplete result, failed to get total"));
> +        goto error;
> +    }
> +
> +    return ret;
> +
> + error:
> +    qemuMonitorEventDumpStatsFree(ret);
> +    return NULL;
> +}
> +
> +
> +static void
> +qemuMonitorJSONHandleDumpCompleted(qemuMonitorPtr mon,
> +                                   virJSONValuePtr data)
> +{
> +    virJSONValuePtr result;
> +    qemuMonitorDumpStatsPtr stats = NULL;
> +    const char *error = NULL;
> +
> +    if (!(result = virJSONValueObjectGetObject(data, "result"))) {
> +        VIR_WARN("missing result in dump completed event");
> +        return;
> +    }
> +
> +    stats = qemuMonitorJSONExtractDumpStats(result);
> +    error = virJSONValueObjectGetString(data, "error");
> +
> +    qemuMonitorEmitDumpCompleted(mon, stats, error);

Using stats allocated on the stack would resolve the memory leak here.

Jirka