Re: [PATCH v2 33/44] error: Avoid unnecessary error_propagate() after error_setg()

[Eric Blake]

On 7/2/20 10:49 AM, Markus Armbruster wrote:
> Replace
>
>      error_setg(&err, ...);
>      error_propagate(errp, err);
>
> by
>
>      error_setg(errp, ...);

> Candidates for conversion tracked down with this Coccinelle script:
>
>      @@
>      identifier err, errp;
>      expression list args;
>      @@
>      -    error_setg(&err, args);
>      +    error_setg(errp, args);
>          ... when != err
>          error_propagate(errp, err);
>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---

> +++ b/backends/cryptodev.c
> @@ -158,16 +158,15 @@ cryptodev_backend_set_queues(Object *obj, Visitor *v, 
> const char *name,
>       uint32_t value;
>   
>       if (!visit_type_uint32(v, name, &value, &local_err)) {
> -        goto out;
> +        error_propagate(errp, local_err);
> +        return;
>       }

Looks like this error_propgate is spurious if you just use
 if (!visit_type_uint32(..., errp)) {

Oh - that's not the pattern you flagged, and a later patch then 
addresses it.  It might help if the commit message for this patch 
mentions that further cleanups are still forthcoming.


> +++ b/backends/hostmem-file.c
> @@ -114,18 +114,16 @@ static void file_memory_backend_set_align(Object *o, 
> Visitor *v,
>       uint64_t val;
>   
>       if (host_memory_backend_mr_inited(backend)) {
> -        error_setg(&local_err, "cannot change property '%s' of %s",
> -                   name, object_get_typename(o));
> -        goto out;
> +        error_setg(errp, "cannot change property '%s' of %s", name,
> +                   object_get_typename(o));
> +        return;
>       }
>   
>       if (!visit_type_size(v, name, &val, &local_err)) {
> -        goto out;
> +        error_propagate(errp, local_err);
> +        return;
>       }

Another case where the first 'if' matches the subject of this patch, and 
the second 'if' can avoid local_err but that the change will be done in 
a later patch.  And several more later on, but this is how far it took 
me to realize that you intentionally saved them for later.

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

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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