Re: [PATCH 1/2] locktorture: doesn't check nreaders_stress when no readlock support

From: Paul E. McKenney
Date: Thu Sep 17 2020 - 12:59:49 EST


On Thu, Sep 17, 2020 at 09:59:09PM +0800, Hou Tao wrote:
> To ensure there is always at least one locking thread.
>
> Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
> ---
> kernel/locking/locktorture.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
> index 9cfa5e89cff7f..bebdf98e6cd78 100644
> --- a/kernel/locking/locktorture.c
> +++ b/kernel/locking/locktorture.c
> @@ -868,7 +868,8 @@ static int __init lock_torture_init(void)
> goto unwind;
> }
>
> - if (nwriters_stress == 0 && nreaders_stress == 0) {
> + if (nwriters_stress == 0 &&
> + (!cxt.cur_ops->readlock || nreaders_stress == 0)) {

You lost me on this one. How does it help to allow tests with zero
writers on exclusive locks? Or am I missing something subtle here?

Thanx, Paul

> pr_alert("lock-torture: must run at least one locking thread\n");
> firsterr = -EINVAL;
> goto unwind;
> --
> 2.25.0.4.g0ad7144999
>