patches/old/mm-vmscan-define-macros-for-refaults-in-struct-lruvec.patch

From: Yang Yang <yang.yang29@zte.com.cn>
Subject: mm/vmscan: define macros for refaults in struct lruvec
Date: Mon, 8 Aug 2022 00:56:45 +0000

The magic number 0 and 1 are used in several places in vmscan.c.
Define macros for them to improve code readability.

Link: https://lkml.kernel.org/r/20220808005644.1721066-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/mmzone.h |    2 ++
 mm/vmscan.c            |    8 ++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

--- a/include/linux/mmzone.h~mm-vmscan-define-macros-for-refaults-in-struct-lruvec
+++ a/include/linux/mmzone.h
@@ -306,6 +306,8 @@ static inline bool is_active_lru(enum lr
 	return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
 }
 
+#define WORKINGSET_ANON 0
+#define WORKINGSET_FILE 1
 #define ANON_AND_FILE 2
 
 enum lruvec_flags {
--- a/mm/vmscan.c~mm-vmscan-define-macros-for-refaults-in-struct-lruvec
+++ a/mm/vmscan.c
@@ -3230,7 +3230,7 @@ again:
 
 		refaults = lruvec_page_state(target_lruvec,
 				WORKINGSET_ACTIVATE_ANON);
-		if (refaults != target_lruvec->refaults[0] ||
+		if (refaults != target_lruvec->refaults[WORKINGSET_ANON] ||
 			inactive_is_low(target_lruvec, LRU_INACTIVE_ANON))
 			sc->may_deactivate |= DEACTIVATE_ANON;
 		else
@@ -3243,7 +3243,7 @@ again:
 		 */
 		refaults = lruvec_page_state(target_lruvec,
 				WORKINGSET_ACTIVATE_FILE);
-		if (refaults != target_lruvec->refaults[1] ||
+		if (refaults != target_lruvec->refaults[WORKINGSET_FILE] ||
 		    inactive_is_low(target_lruvec, LRU_INACTIVE_FILE))
 			sc->may_deactivate |= DEACTIVATE_FILE;
 		else
@@ -3559,9 +3559,9 @@ static void snapshot_refaults(struct mem
 
 	target_lruvec = mem_cgroup_lruvec(target_memcg, pgdat);
 	refaults = lruvec_page_state(target_lruvec, WORKINGSET_ACTIVATE_ANON);
-	target_lruvec->refaults[0] = refaults;
+	target_lruvec->refaults[WORKINGSET_ANON] = refaults;
 	refaults = lruvec_page_state(target_lruvec, WORKINGSET_ACTIVATE_FILE);
-	target_lruvec->refaults[1] = refaults;
+	target_lruvec->refaults[WORKINGSET_FILE] = refaults;
 }
 
 /*
_