Re: [Qemu-devel] [PATCH v4] hmp: add info iothreads command

[Christian Borntraeger <borntraeger@de.ibm.com>]

Am 23.06.2015 um 13:57 schrieb Markus Armbruster:
> Ting Wang <kathy.wangting@huawei.com> writes:
> 
>> Hi Luiz and Markus,
>>
>> Would you like to pick up this patch, which has
>> been reviewed by Stefan and Fam?
> 
> Looks like this fell through the cracks back in March.  You should've
> asked for merge much earlier.  Pinging the maintainer after two weeks is
> fair.
> 
> I just did a monitor pull, and I can't yet say whether I'll do another
> for 2.4.
> 
> Quick review inline.
> 

Is there some patch available that allows someone to query the disks attached to
an iothread (or check if a disk uses iothreads?). I had several testers asking why
x-dataplane is off after specifying iothread. Maybe this information could be
added here as well?



>>
>> Thanks.
>>
>> Ting
>>
>> On 2015-3-13 16:58, Ting Wang wrote:
>>> Make "info iothreads" available on the HMP monitor.
>>>
>>> The results are as follows:
>>> id1: thread_id=thread_id1
>>> id2: thread_id=thread_id2
> 
> Actually, they are like
> 
> id1: thread_id=123
> id2: thread_id=456
> 
> Recommend to paste actual output from your testing.
> 
>>>
>>> Signed-off-by: Ting Wang <kathy.wangting@huawei.com>
>>> ---
>>> v4: use the PRId64 format specifier macro for the int64_t thread_id
>>> v3: fix comment and the trailing whitespace
>>> v2: add braces for if
>>> ---
>>>  hmp-commands.hx |  2 ++
>>>  hmp.c           | 22 ++++++++++++++++++++++
>>>  hmp.h           |  1 +
>>>  monitor.c       |  7 +++++++
>>>  4 files changed, 32 insertions(+)
>>>
>>> diff --git a/hmp-commands.hx b/hmp-commands.hx
>>> index d5022d8..67d76ed 100644
>>> --- a/hmp-commands.hx
>>> +++ b/hmp-commands.hx
>>> @@ -1746,6 +1746,8 @@ show roms
>>>  show the TPM device
>>>  @item info memory-devices
>>>  show the memory devices
>>> +@item info iothreads
>>> +show iothreads
>>>  @end table
>>>  ETEXI
>>>  
>>> diff --git a/hmp.c b/hmp.c
>>> index 71c28bc..445a8ad 100644
>>> --- a/hmp.c
>>> +++ b/hmp.c
>>> @@ -821,6 +821,28 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>>>      qapi_free_TPMInfoList(info_list);
>>>  }
>>>  
>>> +void hmp_info_iothreads(Monitor *mon, const QDict *qdict)
>>> +{
>>> +    IOThreadInfoList *head = NULL, *elem = NULL;
>>> +
>>> +    head = qmp_query_iothreads(NULL);
>>> +    if (!head) {
>>> +        monitor_printf(mon, "No iothread has been added\n");
>>> +        return;
>>> +    }
> 
> Printing something instead of nothing when the list is empty is matter
> of taste.  Consistency would be nice, though.  I know several commands
> that print nothing.  Can you quote commands printing something?
> 
>>> +
>>> +    elem = head;
>>> +    while (elem) {
>>> +        if (elem->value) {
>>> +            monitor_printf(mon, "%s: thread_id=%" PRId64 "\n", elem->value->id,
>>> +                    elem->value->thread_id);
>>> +        }
>>> +        elem = elem->next;
>>> +    }
> 
>     for (info = info_list; info; info = info->next) {
>         monitor_printf(mon, "%s: thread_id=%" PRId64 "\n",
>                        elem->value->id, elem->value->thread_id);
>     }
> 
> 1. for is more readable than while, because it has the full loop control
> in one place.
> 
> 2. List elements cannot be null, so don't bother checking for it.
> 
>>> +
>>> +    qapi_free_IOThreadInfoList(head);
>>> +}
>>> +
>>>  void hmp_quit(Monitor *mon, const QDict *qdict)
>>>  {
>>>      monitor_suspend(mon);
>>> diff --git a/hmp.h b/hmp.h
>>> index 81177b2..d99090e 100644
>>> --- a/hmp.h
>>> +++ b/hmp.h
>>> @@ -38,6 +38,7 @@ void hmp_info_balloon(Monitor *mon, const QDict *qdict);
>>>  void hmp_info_pci(Monitor *mon, const QDict *qdict);
>>>  void hmp_info_block_jobs(Monitor *mon, const QDict *qdict);
>>>  void hmp_info_tpm(Monitor *mon, const QDict *qdict);
>>> +void hmp_info_iothreads(Monitor *mon, const QDict *qdict);
>>>  void hmp_quit(Monitor *mon, const QDict *qdict);
>>>  void hmp_stop(Monitor *mon, const QDict *qdict);
>>>  void hmp_system_reset(Monitor *mon, const QDict *qdict);
>>> diff --git a/monitor.c b/monitor.c
>>> index c86a89e..076a306 100644
>>> --- a/monitor.c
>>> +++ b/monitor.c
>>> @@ -2924,6 +2924,13 @@ static mon_cmd_t info_cmds[] = {
>>>          .mhandler.cmd = hmp_info_memory_devices,
>>>      },
>>>      {
>>> +        .name       = "iothreads",
>>> +        .args_type  = "",
>>> +        .params     = "",
>>> +        .help       = "show iothreads",
>>> +        .mhandler.cmd = hmp_info_iothreads,
>>> +    },
>>> +    {
>>>          .name       = NULL,
>>>      },
>>>  };
>>>
>