Re: [patch 08/25] debugobjects: Provide and use free_object_list()

[Leizhen (ThunderTown)]

On 2024/10/8 0:50, Thomas Gleixner wrote:
> Move the loop to free a list of objects into a helper function so it can be
> reused later.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
>  lib/debugobjects.c |   22 ++++++++++++++++------
>  1 file changed, 16 insertions(+), 6 deletions(-)
> 
> --- a/lib/debugobjects.c
> +++ b/lib/debugobjects.c
> @@ -125,6 +125,20 @@ static const char *obj_states[ODEBUG_STA
>  	[ODEBUG_STATE_NOTAVAILABLE]	= "not available",
>  };
>  
> +static void free_object_list(struct hlist_head *head)
> +{
> +	struct hlist_node *tmp;
> +	struct debug_obj *obj;
> +	int cnt = 0;
> +
> +	hlist_for_each_entry_safe(obj, tmp, head, node) {
> +		hlist_del(&obj->node);
> +		kmem_cache_free(obj_cache, obj);
> +		cnt++;
> +	}
> +	debug_objects_freed += cnt;

debug_objects_freed was previously protected by pool_lock. Use atomic?

> +}
> +
>  static void fill_pool(void)
>  {
>  	gfp_t gfp = __GFP_HIGH | __GFP_NOWARN;
> @@ -286,7 +300,6 @@ alloc_object(void *addr, struct debug_bu
>   */
>  static void free_obj_work(struct work_struct *work)
>  {
> -	struct hlist_node *tmp;
>  	struct debug_obj *obj;
>  	unsigned long flags;
>  	HLIST_HEAD(tofree);
> @@ -323,15 +336,11 @@ static void free_obj_work(struct work_st
>  	 */
>  	if (obj_nr_tofree) {
>  		hlist_move_list(&obj_to_free, &tofree);
> -		debug_objects_freed += obj_nr_tofree;
>  		WRITE_ONCE(obj_nr_tofree, 0);
>  	}
>  	raw_spin_unlock_irqrestore(&pool_lock, flags);
>  
> -	hlist_for_each_entry_safe(obj, tmp, &tofree, node) {
> -		hlist_del(&obj->node);
> -		kmem_cache_free(obj_cache, obj);
> -	}
> +	free_object_list(&tofree);
>  }
>  
>  static void __free_object(struct debug_obj *obj)
> @@ -1334,6 +1343,7 @@ static bool __init debug_objects_replace
>  	}
>  	return true;
>  free:
> +	/* Can't use free_object_list() as the cache is not populated yet */
>  	hlist_for_each_entry_safe(obj, tmp, &objects, node) {
>  		hlist_del(&obj->node);
>  		kmem_cache_free(cache, obj);
> 
> .
> 

-- 
Regards,
  Zhen Lei