Re: [PATCH v3 09/10] migration/dirtyrate: Implement calculate_dirtyrate() function

[Zheng Chuan]

On 2020/8/21 1:57, Dr. David Alan Gilbert wrote:
> * Chuan Zheng (zhengchuan@huawei.com) wrote:
>> Implement calculate_dirtyrate() function.
>>
>> Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
>> Signed-off-by: YanYing Zhuang <ann.zhuangyanying@huawei.com>
>> ---
>>  migration/dirtyrate.c | 46 ++++++++++++++++++++++++++++++++++++++++++++--
>>  1 file changed, 44 insertions(+), 2 deletions(-)
>>
>> diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
>> index 4bbfcc3..041d0c6 100644
>> --- a/migration/dirtyrate.c
>> +++ b/migration/dirtyrate.c
>> @@ -184,6 +184,21 @@ static void get_ramblock_dirty_info(RAMBlock *block,
>>      strcpy(info->idstr, qemu_ram_get_idstr(block));
>>  }
>>  
>> +static void free_ramblock_dirty_info(struct RamblockDirtyInfo *infos, int 
>> count)
>> +{
>> +    int i;
>> +
>> +    if (!infos) {
>> +        return;
>> +    }
>> +
>> +    for (i = 0; i < count; i++) {
>> +        g_free(infos[i].sample_page_vfn);
>> +        g_free(infos[i].hash_result);
>> +    }
>> +    g_free(infos);
>> +}
>> +
>>  static struct RamblockDirtyInfo *
>>  alloc_ramblock_dirty_info(int *block_index,
>>                            struct RamblockDirtyInfo *block_dinfo)
>> @@ -341,8 +356,35 @@ static int compare_page_hash_info(struct 
>> RamblockDirtyInfo *info,
>>  
>>  static void calculate_dirtyrate(struct DirtyRateConfig config)
>>  {
>> -    /* todo */
>> -    return;
>> +    struct RamblockDirtyInfo *block_dinfo = NULL;
>> +    int block_index = 0;
>> +    int64_t msec = 0;
>> +    int64_t initial_time;
>> +
>> +    rcu_register_thread();
>> +    reset_dirtyrate_stat();
>> +    initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
>> +    rcu_read_lock();
>> +    if (record_ramblock_hash_info(&block_dinfo, config, &block_index) < 0) {
>> +        goto out;
>> +    }
>> +    rcu_read_unlock();
>> +
>> +    msec = config.sample_period_seconds * 1000;
>> +    msec = set_sample_page_period(msec, initial_time);
>> +
>> +    rcu_read_lock();
>> +    if (compare_page_hash_info(block_dinfo, block_index) < 0) {
>> +        goto out;
>> +    }
>> +
>> +    update_dirtyrate(msec);
> 
> I think this is OK, so:
> 
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> 
> However, please try the following test,  set it to 60 seconds,
> start the dirty rate check, and in that time, shut the guest down
> (e.g. shutdown -h now in the guest) - what happens?
> 
> Dave
> 
It is ok when shutdown corcurrent with query dirtyrate, the get_dirtyrate
thread is terminated by qemu.

>> +
>> +out:
>> +    rcu_read_unlock();
>> +    free_ramblock_dirty_info(block_dinfo, block_index + 1);
>> +    rcu_unregister_thread();
>> +
>>  }
>>  
>>  void *get_dirtyrate_thread(void *arg)
>> -- 
>> 1.8.3.1
>>