Re: [PATCH v2 2/3] mm: memory-failure: Bump memory failure stats to pglist_data

[Kefeng Wang <wangkefeng.wang@huawei.com>]

On 2023/1/20 11:46, Jiaqi Yan wrote:
> Right before memory_failure finishes its handling, accumulate poisoned
> page's resolution counters to pglist_data's memory_failure_stats, so as
> to update the corresponding sysfs entries.
> 
> Tested:
> 1) Start an application to allocate memory buffer chunks
> 2) Convert random memory buffer addresses to physical addresses
> 3) Inject memory errors using EINJ at chosen physical addresses
> 4) Access poisoned memory buffer and recover from SIGBUS
> 5) Check counter values under
>     /sys/devices/system/node/node*/memory_failure/*
> 
> Acked-by: David Rientjes <rientjes@google.com>
> Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
> ---
>   mm/memory-failure.c | 36 ++++++++++++++++++++++++++++++++++++
>   1 file changed, 36 insertions(+)
> 
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index c628f1db3a4d..f4990839ea66 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -1227,6 +1227,39 @@ static struct page_state error_states[] = {
>   #undef slab
>   #undef reserved
>   
> +static void update_per_node_mf_stats(unsigned long pfn,
> +				     enum mf_result result)
> +{
> +	int nid = MAX_NUMNODES;
> +	struct memory_failure_stats *mf_stats = NULL;
> +
> +	nid = pfn_to_nid(pfn);
> +	if (unlikely(nid < 0 || nid >= MAX_NUMNODES)) {
> +		WARN_ONCE(1, "Memory failure: pfn=%#lx, invalid nid=%d", pfn, nid);
> +		return;
> +	}
> +
...
> +	default:
> +		WARN_ONCE(1, "Memory failure: mf_result=%d is not properly handled", result);
> +		break;
> +	}

We already define pr_fmt, the "Memory failure:" prefix should be dropped.