Re: [PATCH BUGFIX] block: make elevator_get robust against cross blk/blk-mq choice

[Bart Van Assche <Bart.VanAssche@sandisk.com>]

On Mon, 2017-02-13 at 22:01 +0100, Paolo Valente wrote:
> -static struct elevator_type *elevator_get(const char *name, bool try_loa=
ding)
> +static struct elevator_type *elevator_get(const char *name, bool try_loa=
ding,
> +					  bool mq_ops)

Please choose a better name for that argument, e.q. "mq". To me the name "m=
q_ops"
means "a pointer to a data structure with operation function pointers".

> +	if (e && (e->uses_mq !=3D mq_ops)) {
> +		pr_err("ERROR: attempted to choose %s %s I/O scheduler in blk%s",
> +		       name, e->uses_mq ? "blk-mq" : "legacy", mq_ops ? "-mq" : "");
> +		e =3D NULL;
> +	}

How about changing the above into:

+=A0=A0=A0=A0=A0=A0=A0if (e && e->uses_mq !=3D mq) {
+=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0pr_err("ERROR: attempt to con=
figure %s as I/O scheduler for a %s queue\n",
+=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0name, mq=
 ? "blk-mq" : "legacy");
+=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0e =3D NULL;
+=A0=A0=A0=A0=A0=A0=A0}

Thanks,

Bart.
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