Re: [PATCH] mm/memcontrol: remove unused memcg parameter in calculate_high_delay()

[Michal Hocko]

On Tue 25-08-26 20:01:53, Hongfu Li wrote:
> From: Hongfu Li <lihongfu@xxxxxxxxxx>
> 
> The memcg argument of calculate_high_delay() is never referenced in
> its function body. The delay calculation only depends on nr_pages
> and max_overage, and both callers have already obtained max_overage
> from the same memcg.
> 
> Drop this unused parameter and update the two call sites inside
> __mem_cgroup_handle_over_high().
> 
> Signed-off-by: Hongfu Li <lihongfu@xxxxxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

Thanks!

> ---
>  mm/memcontrol.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 11b85f4b6828..8bdb6988e7f0 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2515,8 +2515,7 @@ static u64 swap_find_max_overage(struct mem_cgroup *memcg)
>   * Get the number of jiffies that we should penalise a mischievous cgroup which
>   * is exceeding its memory.high by checking both it and its ancestors.
>   */
> -static unsigned long calculate_high_delay(struct mem_cgroup *memcg,
> -					  unsigned int nr_pages,
> +static unsigned long calculate_high_delay(unsigned int nr_pages,
>  					  u64 max_overage)
>  {
>  	unsigned long penalty_jiffies;
> @@ -2594,10 +2593,10 @@ void __mem_cgroup_handle_over_high(gfp_t gfp_mask)
>  	 * memory.high is breached and reclaim is unable to keep up. Throttle
>  	 * allocators proactively to slow down excessive growth.
>  	 */
> -	penalty_jiffies = calculate_high_delay(memcg, nr_pages,
> +	penalty_jiffies = calculate_high_delay(nr_pages,
>  					       mem_find_max_overage(memcg));
>  
> -	penalty_jiffies += calculate_high_delay(memcg, nr_pages,
> +	penalty_jiffies += calculate_high_delay(nr_pages,
>  						swap_find_max_overage(memcg));
>  
>  	/*
> -- 
> 2.54.0

-- 
Michal Hocko
SUSE Labs