[Engine-devel] LockManager maybe not be really taking locks in your flows...

[Roy Golan]

On Sun 11 Aug 2013 05:14:04 PM IDT, Roy Golan wrote:
> On Sun 11 Aug 2013 05:03:05 PM IDT, Yair Zaslavsky wrote:
>> Hi all,
>> Thanks to Alon Bar Lev's efforts for preventing to concurrent host
>> installation for the same host entity + Roy Golan's check of the
>> code, we saw that for commands that override
>>
>> getExclusiveLocks() or getSharedLocks() the locking mechanism does
>> not work (lock is not being acquired) if there is no annotation of
>> @LockIdNameAttribute on the class.
>> A bug was filed for removing this annotation (leftover from some
>> historical code ) , but until it is fixed - bare in mind you need to
>> add this annotation in current commands you are working on
>> in order to utilize the mechanism.
>> See RemoveVmCommand (has the annotation) vs AddDiskCommand (which
>> doesn't have the annotation)
>>
>>
>> Cheers,
>> Yair
>> _______________________________________________
>> Engine-devel mailing list
>> Engine-devel at ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/engine-devel
>
> just to make it clear, the storage commands are calling explicitly
> aquireLockInternal in the canDoAction. since there is no contract (no
> interface) we are open to mistakes and misuse. this should be rectified.
>
more info from the bug:
see the list of commands that overrrides getExcelusiveLocks but *don't* 
have the @LockIdNameAttribute annotation:

bll/src/main/java/org/ovirt/engine/core/bll/AddDiskCommand.java
bll/src/main/java/org/ovirt/engine/core/bll/MoveOrCopyDiskCommand.java
bll/src/main/java/org/ovirt/engine/core/bll/AddVdsCommand.java
bll/src/main/java/org/ovirt/engine/core/bll/UpdateVmTemplateCommand.java
bll/src/main/java/org/ovirt/engine/core/bll/ExportRepoImageCommand.java