[libvirt] [PATCH REBASE 1/5] qemu: erase synchronous block job cancel mentions in comments

[Nikolay Shirokovskiy]

On 01.05.2018 01:03, John Ferlan wrote:
> 
> 
> On 04/18/2018 10:44 AM, Nikolay Shirokovskiy wrote:
>> Commit [1] dropped support for synchronous block job cancel.
>> This patch erases remnants from comments.
>>
>> [1] commit 2350d101 "qemu: Remove support for legacy block jobs"
>>
>> Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy at virtuozzo.com>
>> ---
>>  src/qemu/qemu_driver.c | 13 ++++++-------
>>  1 file changed, 6 insertions(+), 7 deletions(-)
>>
>> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
>> index 4e06c9c..0dd6032 100644
>> --- a/src/qemu/qemu_driver.c
>> +++ b/src/qemu/qemu_driver.c
>> @@ -16914,13 +16914,12 @@ qemuDomainBlockJobAbort(virDomainPtr dom,
>>      if (save)
>>          ignore_value(virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, driver->caps));
>>  
>> -    /* With synchronous block cancel, we must synthesize an event, and
>> -     * we silently ignore the ABORT_ASYNC flag.  With asynchronous
>> -     * block cancel, the event will come from qemu and will update the
>> -     * XML as appropriate, but without the ABORT_ASYNC flag, we must
>> -     * block to guarantee synchronous operation.  We do the waiting
>> -     * while still holding the VM job, to prevent newly scheduled
>> -     * block jobs from confusing us.  */
>> +    /*
>> +     * With asynchronous block cancel, the event will come from qemu and will
> 
> /* With...
> 
> IOW: don't have a separate line for the open comment...
> 
>> +     * update the XML as appropriate, but without the ABORT_ASYNC flag, we must
>> +     * block to guarantee synchronous operation.  We do the waiting while still
>> +     * holding the VM job, to prevent newly scheduled block jobs from confusing
>> +     * us. */
> 
> This works, but the lead-in doesn't mean as much without the "With
> synchronous..." as the alternative...  So perhaps even simpler:
> 
> Wait for the QEMU event to update the the blockjob with the domain lock
> to prevent newly scheduled block jobs from confusing us. The event will
> update the XML as appropriate. Without the ABORT_ASYNC flag, we must
> block to guarantee synchronous completion.
> 
> With at least the comment entry fixup... feel free to use my wording as
> well (as long as it makes sense to you)..
I can not use your version unchanged too... It starts saying that we wait but
we wait only if ABORT_ASYNC is not set. I'll reword the proposed version
too to eliminate the mention that we use qemu's async block job cancel
API.

> 
> Reviewed-by: John Ferlan <jferlan at redhat.com>
> 
> but please wait for 4.4.0 to open before pushing.
> 
> John
> 
> 
>>      if (!async) {
>>          qemuDomainDiskPrivatePtr diskPriv = QEMU_DOMAIN_DISK_PRIVATE(disk);
>>          qemuBlockJobUpdate(driver, vm, QEMU_ASYNC_JOB_NONE, disk, NULL);
>>