Re: [patch V2 15/17] mm/vmscan: Adjust system_state checks

[Vlastimil Babka]

On 05/16/2017 08:42 PM, Thomas Gleixner wrote:
> To enable smp_processor_id() and might_sleep() debug checks earlier, it's
> required to add system states between SYSTEM_BOOTING and SYSTEM_RUNNING.
> 
> Adjust the system_state check in kswapd_run() to handle the extra states.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Vlastimil Babka <vbabka@xxxxxxx>
> Cc: linux-mm@xxxxxxxxx

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>  mm/vmscan.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -3643,7 +3643,7 @@ int kswapd_run(int nid)
>  	pgdat->kswapd = kthread_run(kswapd, pgdat, "kswapd%d", nid);
>  	if (IS_ERR(pgdat->kswapd)) {
>  		/* failure at boot is fatal */
> -		BUG_ON(system_state == SYSTEM_BOOTING);
> +		BUG_ON(system_state < SYSTEM_RUNNING);
>  		pr_err("Failed to start kswapd on node %d\n", nid);
>  		ret = PTR_ERR(pgdat->kswapd);
>  		pgdat->kswapd = NULL;
> 
>