[RFC][PATCH 02/12] mm/vmscan: move RECLAIM* bits to uapi header

[Dave Hansen]

From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>

It is currently not obvious that the RECLAIM_* bits are part of the
uapi since they are defined in vmscan.c.  Move them to a uapi header
to make it obvious.

This should have no functional impact.

Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Reviewed-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Cc: Daniel Wagner <dwagner@xxxxxxx>
Cc: "Tobin C. Harding" <tobin@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Daniel Wagner <dwagner@xxxxxxx>

--

Note: This is not cc'd to stable.  It does not fix any bugs.
---

 b/include/uapi/linux/mempolicy.h |    7 +++++++
 b/mm/vmscan.c                    |    8 --------
 2 files changed, 7 insertions(+), 8 deletions(-)

diff -puN include/uapi/linux/mempolicy.h~mm-vmscan-move-RECLAIM-bits-to-uapi include/uapi/linux/mempolicy.h
--- a/include/uapi/linux/mempolicy.h~mm-vmscan-move-RECLAIM-bits-to-uapi	2020-10-06 13:39:21.720818440 -0700
+++ b/include/uapi/linux/mempolicy.h	2020-10-06 13:39:21.726818440 -0700
@@ -62,5 +62,12 @@ enum {
 #define MPOL_F_MOF	(1 << 3) /* this policy wants migrate on fault */
 #define MPOL_F_MORON	(1 << 4) /* Migrate On protnone Reference On Node */
 
+/*
+ * These bit locations are exposed in the vm.zone_reclaim_mode sysctl
+ * ABI.  New bits are OK, but existing bits can never change.
+ */
+#define RECLAIM_ZONE	(1<<0)	/* Run shrink_inactive_list on the zone */
+#define RECLAIM_WRITE	(1<<1)	/* Writeout pages during reclaim */
+#define RECLAIM_UNMAP	(1<<2)	/* Unmap pages during reclaim */
 
 #endif /* _UAPI_LINUX_MEMPOLICY_H */
diff -puN mm/vmscan.c~mm-vmscan-move-RECLAIM-bits-to-uapi mm/vmscan.c
--- a/mm/vmscan.c~mm-vmscan-move-RECLAIM-bits-to-uapi	2020-10-06 13:39:21.722818440 -0700
+++ b/mm/vmscan.c	2020-10-06 13:39:21.727818440 -0700
@@ -4084,14 +4084,6 @@ module_init(kswapd_init)
 int node_reclaim_mode __read_mostly;
 
 /*
- * These bit locations are exposed in the vm.zone_reclaim_mode sysctl
- * ABI.  New bits are OK, but existing bits can never change.
- */
-#define RECLAIM_ZONE  (1<<0)   /* Run shrink_inactive_list on the zone */
-#define RECLAIM_WRITE (1<<1)   /* Writeout pages during reclaim */
-#define RECLAIM_UNMAP (1<<2)   /* Unmap pages during reclaim */
-
-/*
  * Priority for NODE_RECLAIM. This determines the fraction of pages
  * of a node considered for each zone_reclaim. 4 scans 1/16th of
  * a zone.
_