Re: [PATCH 1/3] dcache: add a new enum type for 'dentry_d_lock_class'

[Greg KH]

On Fri, Nov 15, 2019 at 11:27:50AM +0800, yu kuai wrote:
> 'dentry_d_lock_class' can be used for spin_lock_nested in case lockdep
> confused about two different dentry take the 'd_lock'.
> 
> However, a single 'DENTRY_D_LOCK_NESTED' may not be enough if more than
> two dentry are involed. So, and in 'DENTRY_D_LOCK_NESTED_2'
> 
> Signed-off-by: yu kuai <yukuai3@xxxxxxxxxx>
> ---
>  include/linux/dcache.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/dcache.h b/include/linux/dcache.h
> index 10090f1..8eb84ef 100644
> --- a/include/linux/dcache.h
> +++ b/include/linux/dcache.h
> @@ -129,7 +129,8 @@ struct dentry {
>  enum dentry_d_lock_class
>  {
>  	DENTRY_D_LOCK_NORMAL, /* implicitly used by plain spin_lock() APIs. */
> -	DENTRY_D_LOCK_NESTED
> +	DENTRY_D_LOCK_NESTED,
> +	DENTRY_D_LOCK_NESTED_2

You should document this, as "_2" does not make much sense to anyone
only looking at the code :(

Or rename it better.

thanks,

greg k-h