Re: [PATCH rcu 3/7] locking: Reduce the number of locks in ww_mutex stress tests

[Paul E. McKenney]

On Thu, Mar 16, 2023 at 08:13:35PM -0700, Boqun Feng wrote:
> The stress test in test_ww_mutex_init() uses 4095 locks since
> lockdep::reference has 12 bits, and since we are going to reduce it to
> 11 bits to support lock_sync(), and 2047 is still a reasonable number of
> the max nesting level for locks, so adjust the test.
> 
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> Link: https://lore.kernel.org/oe-lkp/202302011445.9d99dae2-oliver.sang@xxxxxxxxx
> Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>

Tested-by: Paul E. McKenney <paulmck@xxxxxxxxxx>

> ---
>  kernel/locking/test-ww_mutex.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
> index 29dc253d03af..93cca6e69860 100644
> --- a/kernel/locking/test-ww_mutex.c
> +++ b/kernel/locking/test-ww_mutex.c
> @@ -659,7 +659,7 @@ static int __init test_ww_mutex_init(void)
>  	if (ret)
>  		return ret;
>  
> -	ret = stress(4095, hweight32(STRESS_ALL)*ncpus, STRESS_ALL);
> +	ret = stress(2047, hweight32(STRESS_ALL)*ncpus, STRESS_ALL);
>  	if (ret)
>  		return ret;
>  
> -- 
> 2.39.2
>