The patch titled
Subject: mm: use unsigned types for fragmentation score
has been added to the -mm tree. Its filename is
mm-use-unsigned-types-for-fragmentation-score.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-use-unsigned-types-for-fragmentation-score.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-use-unsigned-types-for-fragmentation-score.patch
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------------------------------------------------------
From: Nitin Gupta <nigupta@xxxxxxxxxx>
Subject: 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.
Link: http://lkml.kernel.org/r/20200618010319.13159-1-nigupta@xxxxxxxxxx
Signed-off-by: Nitin Gupta <nigupta@xxxxxxxxxx>
Reviewed-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Iurii Zaikin <yzaikin@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/compaction.h | 4 ++--
kernel/sysctl.c | 2 +-
mm/compaction.c | 18 +++++++++---------
mm/vmstat.c | 2 +-
4 files changed, 13 insertions(+), 13 deletions(-)
--- a/include/linux/compaction.h~mm-use-unsigned-types-for-fragmentation-score
+++ a/include/linux/compaction.h
@@ -85,13 +85,13 @@ static inline unsigned long compact_gap(
#ifdef CONFIG_COMPACTION
extern int sysctl_compact_memory;
-extern int sysctl_compaction_proactiveness;
+extern unsigned int sysctl_compaction_proactiveness;
extern int sysctl_compaction_handler(struct ctl_table *table, int write,
void *buffer, size_t *length, loff_t *ppos);
extern int sysctl_extfrag_threshold;
extern int sysctl_compact_unevictable_allowed;
-extern int extfrag_for_order(struct zone *zone, unsigned int order);
+extern unsigned int extfrag_for_order(struct zone *zone, unsigned int order);
extern int fragmentation_index(struct zone *zone, unsigned int order);
extern enum compact_result try_to_compact_pages(gfp_t gfp_mask,
unsigned int order, unsigned int alloc_flags,
--- a/kernel/sysctl.c~mm-use-unsigned-types-for-fragmentation-score
+++ a/kernel/sysctl.c
@@ -2833,7 +2833,7 @@ static struct ctl_table vm_table[] = {
{
.procname = "compaction_proactiveness",
.data = &sysctl_compaction_proactiveness,
- .maxlen = sizeof(int),
+ .maxlen = sizeof(sysctl_compaction_proactiveness),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
--- a/mm/compaction.c~mm-use-unsigned-types-for-fragmentation-score
+++ a/mm/compaction.c
@@ -53,7 +53,7 @@ static inline void count_compact_events(
/*
* 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
* 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(stru
* 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_d
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
--- a/mm/vmstat.c~mm-use-unsigned-types-for-fragmentation-score
+++ a/mm/vmstat.c
@@ -1101,7 +1101,7 @@ static int __fragmentation_index(unsigne
* It is defined as the percentage of pages found in blocks of size
* less than 1 << order. It returns values in range [0, 100].
*/
-int extfrag_for_order(struct zone *zone, unsigned int order)
+unsigned int extfrag_for_order(struct zone *zone, unsigned int order)
{
struct contig_page_info info;
_
Patches currently in -mm which might be from nigupta@xxxxxxxxxx are
mm-proactive-compaction.patch
mm-use-unsigned-types-for-fragmentation-score.patch
