Re: [PATCH] vmscan: return NODE_RECLAIM_NOSCAN in node_reclaim() when CONFIG_NUMA is n

[Matthew Wilcox]

On Tue, Nov 13, 2018 at 12:17:50PM +0800, Wei Yang wrote:
> Commit fa5e084e43eb ("vmscan: do not unconditionally treat zones that
> fail zone_reclaim() as full") changed the return value of node_reclaim().
> The original return value 0 means NODE_RECLAIM_SOME after this commit.
> 
> While the return value of node_reclaim() when CONFIG_NUMA is n is not
> changed. This will leads to call zone_watermark_ok() again.
> 
> This patch fix the return value by adjusting to NODE_RECLAIM_NOSCAN. Since
> it is not proper to include "mm/internal.h", just hard coded it.

Since the return value is defined in mm/internal.h that means no code
outside mm/ can call node_reclaim (nor should it).  So let's move both
of node_reclaim's declarations to mm/internal.h instead of keeping them
in linux/swap.h.