[PATCH v2 hmm 10/11] mm/hmm: Do not use list*_rcu() for hmm->ranges

[Ralph Campbell]

On 6/6/19 11:44 AM, Jason Gunthorpe wrote:
> From: Jason Gunthorpe <jgg at mellanox.com>
> 
> This list is always read and written while holding hmm->lock so there is
> no need for the confusing _rcu annotations.
> 
> Signed-off-by: Jason Gunthorpe <jgg at mellanox.com>
> Reviewed-by: Jérôme Glisse <jglisse at redhat.com>

Reviewed-by: Ralph Campbell <rcampbell at nvidia.com>

> ---
>   mm/hmm.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/hmm.c b/mm/hmm.c
> index c2fecb3ecb11e1..709d138dd49027 100644
> --- a/mm/hmm.c
> +++ b/mm/hmm.c
> @@ -911,7 +911,7 @@ int hmm_range_register(struct hmm_range *range,
>   	mutex_lock(&hmm->lock);
>   
>   	range->hmm = hmm;
> -	list_add_rcu(&range->list, &hmm->ranges);
> +	list_add(&range->list, &hmm->ranges);
>   
>   	/*
>   	 * If there are any concurrent notifiers we have to wait for them for
> @@ -941,7 +941,7 @@ void hmm_range_unregister(struct hmm_range *range)
>   		return;
>   
>   	mutex_lock(&hmm->lock);
> -	list_del_rcu(&range->list);
> +	list_del(&range->list);
>   	mutex_unlock(&hmm->lock);
>   
>   	/* Drop reference taken by hmm_range_register() */
>