Re: [Qemu-devel] [PATCH v5 03/15] block: add BlockJob interface for long-running operations

[Kevin Wolf <kwolf@redhat.com>]

Am 17.01.2012 14:33, schrieb Stefan Hajnoczi:
> On Tue, Jan 17, 2012 at 1:00 PM, Kevin Wolf <kwolf@redhat.com> wrote:
>> Am 13.01.2012 14:14, schrieb Stefan Hajnoczi:
>>> +typedef struct BlockJobType {
>>> +    /** Derived BlockJob struct size */
>>> +    size_t instance_size;
>>> +
>>> +    /** String describing the operation, part of query-block-jobs QMP API */
>>> +    const char *job_type;
>>> +
>>> +    /** Optional callback for job types that support setting a speed limit */
>>> +    int (*set_speed)(BlockJob *job, int64_t value);
>>
>> Would be worth mentioning what the unit of value is.
> 
> I left this open on purpose so future block jobs could support
> block_job_set_speed with whatever unit makes sense for them.  At the
> interface level it's an arbitrary int64_t.  Each block job type can
> decide how to interpret the values.

I see.

> I could add "The meaning of value and its units depend on the block
> job type".  Or do you think it's problematic to allow different
> meanings?

Might be confusing to have different meanings. But we can leave it open
for now and commit the comment as it is.

Kevin