Re: [PATCH v2] Port hierarchical_{memory,swap}_limit cgroup1->cgroup2

[Waiman Long <longman@xxxxxxxxxx>]

On 2/11/24 07:49, Jan Kratochvil (Azul) wrote:
> Hello Waiman,
>
> On Fri, 09 Feb 2024 23:51:54 +0800, Waiman Long wrote:
> > I don't think we use mi->memsw in cgroup v2, only memory and swap should
> > be used.
> you are right, thanks:
>
> struct mem_cgroup {
> ...
> 	union {
> 		struct page_counter swap;       /* v2 only */
> 		struct page_counter memsw;      /* v1 only */
> 	};
>
>
> Jan Kratochvil
>
>
> Signed-off-by: Jan Kratochvil (Azul) <jkratochvil@xxxxxxxx>

Please send a proper v2 patch to the full list for review.

Cheers,
Longman

>   mm/memcontrol.c | 13 +++++++++++++
>   1 file changed, 13 insertions(+)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 46d8d0211..2631dd810 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1636,6 +1636,8 @@ static inline unsigned long memcg_page_state_local_output(
>   static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s)
>   {
>   	int i;
> +	unsigned long memory, swap;
> +	struct mem_cgroup *mi;
>   
>   	/*
>   	 * Provide statistics on the state of the memory subsystem as
> @@ -1682,6 +1684,17 @@ static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s)
>   			       memcg_events(memcg, memcg_vm_event_stat[i]));
>   	}
>   
> +	/* Hierarchical information */
> +	memory = swap = PAGE_COUNTER_MAX;
> +	for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) {
> +		memory = min(memory, READ_ONCE(mi->memory.max));
> +		swap = min(swap, READ_ONCE(mi->swap.max));
> +	}
> +	seq_buf_printf(s, "hierarchical_memory_limit %llu\n",
> +		       (u64)memory * PAGE_SIZE);
> +	seq_buf_printf(s, "hierarchical_swap_limit %llu\n",
> +		       (u64)swap * PAGE_SIZE);
> +
>   	/* The above should easily fit into one page */
>   	WARN_ON_ONCE(seq_buf_has_overflowed(s));
>   }