Re: [PATCH 1/9] memcg: accounting for allocations called with disabled BH

[Michal Hocko <mhocko@suse.com>]

On Tue 09-03-21 11:03:48, Vasily Averin wrote:
> in_interrupt() check in memcg_kmem_bypass() is incorrect because
> it does not allow to account memory allocation called from task context
> with disabled BH, i.e. inside spin_lock_bh()/spin_unlock_bh() sections

Is there any existing user in the tree? Or is this more of a preparatory
patch for a later one which will need it? In other words, is this a bug
fix or a preparatory work.

> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
> ---
>  mm/memcontrol.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 845eec0..568f2cb 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1076,7 +1076,7 @@ static __always_inline bool memcg_kmem_bypass(void)
>  		return false;
>  
>  	/* Memcg to charge can't be determined. */
> -	if (in_interrupt() || !current->mm || (current->flags & PF_KTHREAD))
> +	if (!in_task() || !current->mm || (current->flags & PF_KTHREAD))
>  		return true;
>  
>  	return false;
> -- 
> 1.8.3.1

-- 
Michal Hocko
SUSE Labs