mm: use unsigned types for fragmentation score
Proactive compaction uses per-node/zone "fragmentation score" which is
always in range [0, 100], so use unsigned type of these scores as well as
for related constants.
Signed-off-by: Nitin Gupta <nigupta@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/20200618010319.13159-1-nigupta@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/compaction.c b/mm/compaction.c
index ed8ea15..b7d433f 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -53,7 +53,7 @@ static inline void count_compact_events(enum vm_event_item item, long delta)
/*
* Fragmentation score check interval for proactive compaction purposes.
*/
-static const int HPAGE_FRAG_CHECK_INTERVAL_MSEC = 500;
+static const unsigned int HPAGE_FRAG_CHECK_INTERVAL_MSEC = 500;
/*
* Page order with-respect-to which proactive compaction
@@ -1890,7 +1890,7 @@ static bool kswapd_is_running(pg_data_t *pgdat)
* ZONE_DMA32. For smaller zones, the score value remains close to zero,
* and thus never exceeds the high threshold for proactive compaction.
*/
-static int fragmentation_score_zone(struct zone *zone)
+static unsigned int fragmentation_score_zone(struct zone *zone)
{
unsigned long score;
@@ -1906,9 +1906,9 @@ static int fragmentation_score_zone(struct zone *zone)
* the node's score falls below the low threshold, or one of the back-off
* conditions is met.
*/
-static int fragmentation_score_node(pg_data_t *pgdat)
+static unsigned int fragmentation_score_node(pg_data_t *pgdat)
{
- unsigned long score = 0;
+ unsigned int score = 0;
int zoneid;
for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
@@ -1921,17 +1921,17 @@ static int fragmentation_score_node(pg_data_t *pgdat)
return score;
}
-static int fragmentation_score_wmark(pg_data_t *pgdat, bool low)
+static unsigned int fragmentation_score_wmark(pg_data_t *pgdat, bool low)
{
- int wmark_low;
+ unsigned int wmark_low;
/*
* Cap the low watermak to avoid excessive compaction
* activity in case a user sets the proactivess tunable
* close to 100 (maximum).
*/
- wmark_low = max(100 - sysctl_compaction_proactiveness, 5);
- return low ? wmark_low : min(wmark_low + 10, 100);
+ wmark_low = max(100U - sysctl_compaction_proactiveness, 5U);
+ return low ? wmark_low : min(wmark_low + 10, 100U);
}
static bool should_proactive_compact_node(pg_data_t *pgdat)
@@ -2615,7 +2615,7 @@ int sysctl_compact_memory;
* aggressively the kernel should compact memory in the
* background. It takes values in the range [0, 100].
*/
-int __read_mostly sysctl_compaction_proactiveness = 20;
+unsigned int __read_mostly sysctl_compaction_proactiveness = 20;
/*
* This is the entry point for compacting all nodes via