Re: [PATCH 3/4] error: Remove NULL checks on error_propagate() calls (again)

[Markus Armbruster]

Markus Armbruster <armbru@redhat.com> writes:

> Eric Blake <eblake@redhat.com> writes:
>
>> On 7/22/20 3:40 AM, Markus Armbruster wrote:
>>> Patch created mechanically by rerunning:
>>>
>>>      $ spatch --sp-file scripts/coccinelle/error_propagate_null.cocci \
>>>               --macro-file scripts/cocci-macro-file.h \
>>>               --use-gitgrep .
>>>
>>> Cc: Jens Freimann <jfreimann@redhat.com>
>>> Cc: Hailiang Zhang <zhang.zhanghailiang@huawei.com>
>>> Cc: Juan Quintela <quintela@redhat.com>
>>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>>> ---
>>
>>> +++ b/migration/colo.c
>>> @@ -798,9 +798,7 @@ static void 
>>> colo_incoming_process_checkpoint(MigrationIncomingState *mis,
>>>         colo_send_message(mis->to_src_file,
>>> COLO_MESSAGE_VMSTATE_LOADED,
>>>                    &local_err);
>>> -    if (local_err) {
>>> -        error_propagate(errp, local_err);
>>> -    }
>>> +    error_propagate(errp, local_err);
>>>   }
>>
>> As this is mechanical, it is fine. But there is now a further cleanup
>> possible of passing errp directly to colo_send_message, and possibly
>> dropping local_err altogether.
>
> True.
>
> The patch is small and simple enough for squashing in further manual
> cleanups.  I'd like to first check whether a followup patch created with
> the machinery I used for eliminating error_propagate() comes out better.

Vladimir's scripts/coccinelle/errp-guard.cocci will take care of it.

Eliminating error propagation altogether would be even better, but it's
also more work: several void functions need to return bool instead.

>> Reviewed-by: Eric Blake <eblake@redhat.com>
>
> Thanks!