On 2020/8/26 18:26, David Edmondson wrote:
> On Monday, 2020-08-24 at 17:14:39 +08, Chuan Zheng wrote:
>
>> Implement qmp_cal_dirty_rate()/qmp_get_dirty_rate() function which could be
>> called
>>
>> Signed-off-by: Chuan Zheng <zhengch...@huawei.com>
>> ---
>> migration/dirtyrate.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
>> qapi/migration.json | 44 ++++++++++++++++++++++++++++++++++++++++++++
>> 2 files changed, 89 insertions(+)
>>
>> diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
>> index 9f52f5f..08c46d3 100644
>> --- a/migration/dirtyrate.c
>> +++ b/migration/dirtyrate.c
>> @@ -62,6 +62,28 @@ static int dirtyrate_set_state(int *state, int old_state,
>> int new_state)
>> }
>> }
>>
>> +static struct DirtyRateInfo *query_dirty_rate_info(void)
>> +{
>> + int64_t dirty_rate = DirtyStat.dirty_rate;
>> + struct DirtyRateInfo *info = g_malloc0(sizeof(DirtyRateInfo));
>> +
>> + if (CalculatingState == DIRTY_RATE_STATUS_MEASURED) {
>> + info->dirty_rate = dirty_rate;
>> + } else {
>> + info->dirty_rate = -1;
>> + }
>> +
>> + info->status = CalculatingState;
>> + /*
>> + * Only support query once for each calculation,
>> + * reset as DIRTY_RATE_STATUS_UNSTARTED after query
>> + */
>> + (void)dirtyrate_set_state(&CalculatingState, CalculatingState,
>> + DIRTY_RATE_STATUS_UNSTARTED);
>
> Is there a reason for this restriction? Removing it would require
> clarifying the state model, I suppose.
>
We only support query once for each calculation.
Otherwise, it could always query dirtyrate, but maybe the dirtyrate is
calculated
long time ago.
>> +
>> + return info;
>> +}
>> +
>> static void reset_dirtyrate_stat(void)
>> {
>> DirtyStat.total_dirty_samples = 0;
>> @@ -378,3 +400,26 @@ void *get_dirtyrate_thread(void *arg)
>> DIRTY_RATE_STATUS_MEASURED);
>> return NULL;
>> }
>> +
>> +void qmp_calc_dirty_rate(int64_t calc_time, Error **errp)
>> +{
>> + static struct DirtyRateConfig config;
>> + QemuThread thread;
>> +
>> + /*
>> + * We don't begin calculating thread only when it's in calculating
>> status.
>
> "If the dirty rate is already being measured, don't attempt to start."
>
>> + */
>> + if (CalculatingState == DIRTY_RATE_STATUS_MEASURING) {
>
> Should this return an error to the caller?
>
>> + return;
>> + }
>> +
>> + config.sample_period_seconds = get_sample_page_period(calc_time);
>
> If the specified sample period is outside the min/max, should an error
> be returned to the caller?
>
>> + config.sample_pages_per_gigabytes = DIRTYRATE_DEFAULT_SAMPLE_PAGES;
>> + qemu_thread_create(&thread, "get_dirtyrate", get_dirtyrate_thread,
>> + (void *)&config, QEMU_THREAD_DETACHED);
>> +}
>> +
>> +struct DirtyRateInfo *qmp_query_dirty_rate(Error **errp)
>> +{
>> + return query_dirty_rate_info();
>> +}
>> diff --git a/qapi/migration.json b/qapi/migration.json
>> index d640165..826bfd7 100644
>> --- a/qapi/migration.json
>> +++ b/qapi/migration.json
>> @@ -1737,3 +1737,47 @@
>> ##
>> { 'enum': 'DirtyRateStatus',
>> 'data': [ 'unstarted', 'measuring', 'measured'] }
>> +
>> +##
>> +# @DirtyRateInfo:
>> +#
>> +# Information about current dirty page rate of vm.
>> +#
>> +# @dirty-rate: @dirtyrate describing the dirty page rate of vm
>> +# in units of MB/s.
>> +# If this field return '-1', it means querying is not
>> +# start or not complete.
>> +#
>> +# @status: status containing dirtyrate query status includes
>> +# 'unstarted' or 'measuring' or 'measured'
>> +#
>> +# Since: 5.2
>> +#
>> +##
>> +{ 'struct': 'DirtyRateInfo',
>> + 'data': {'dirty-rate': 'int64',
>> + 'status': 'DirtyRateStatus'} }
>> +
>> +##
>> +# @calc-dirty-rate:
>> +#
>> +# start calculating dirty page rate for vm
>> +#
>> +# @calc-time: time in units of second for sample dirty pages
>> +#
>> +# Since: 5.2
>> +#
>> +# Example:
>> +# {"command": "cal-dirty-rate", "data": {"calc-time": 1} }
>
> "cal-dirty-rate" -> "calc-dirty-rate".
>
>> +#
>> +##
>> +{ 'command': 'calc-dirty-rate', 'data': {'calc-time': 'int64'} }
>> +
>> +##
>> +# @query-dirty-rate:
>> +#
>> +# query dirty page rate in units of MB/s for vm
>> +#
>> +# Since: 5.2
>> +##
>> +{ 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
>> --
>> 1.8.3.1
>
> dme.
>
