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Date:   Sun, 28 Feb 2021 16:53:32 -0800
From:   Roman Gushchin <guro@fb.com>
To:     Hugh Dickins <hughd@google.com>
CC:     Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 4/4] mm: /proc//sys/vm/stat_refresh stop checking
 monotonic numa stats
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On Thu, Feb 25, 2021 at 03:15:42PM -0800, Hugh Dickins wrote:
> All of the VM NUMA stats are event counts, incremented never decremented:
> it is not very useful for vmstat_refresh() to check them throughout their
> first aeon, then warn on them throughout their next.
> 
> Signed-off-by: Hugh Dickins <hughd@google.com>

Acked-by: Roman Gushchin <guro@fb.com>

Thanks!

> ---
> 
>  mm/vmstat.c |    9 ---------
>  1 file changed, 9 deletions(-)
> 
> --- vmstat3/mm/vmstat.c	2021-02-25 12:42:15.000000000 -0800
> +++ vmstat4/mm/vmstat.c	2021-02-25 12:44:20.000000000 -0800
> @@ -1854,15 +1854,6 @@ int vmstat_refresh(struct ctl_table *tab
>  				__func__, zone_stat_name(i), val);
>  		}
>  	}
> -#ifdef CONFIG_NUMA
> -	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
> -		val = atomic_long_read(&vm_numa_stat[i]);
> -		if (val < 0) {
> -			pr_warn("%s: %s %ld\n",
> -				__func__, numa_stat_name(i), val);
> -		}
> -	}
> -#endif
>  	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
>  		/*
>  		 * Skip checking stats known to go negative occasionally.