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 <[email protected]>
---
include/linux/compaction.h | 4 ++--
kernel/sysctl.c | 2 +-
mm/compaction.c | 18 +++++++++---------
mm/vmstat.c | 2 +-
4 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index 7a242d46454e..25a521d299c1 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -85,13 +85,13 @@ static inline unsigned long compact_gap(unsigned int order)
#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,
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 58b0a59c9769..40180cdde486 100644
--- a/kernel/sysctl.c
+++ b/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,
diff --git a/mm/compaction.c b/mm/compaction.c
index ac2030814edb..45fd24a0ea0b 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)
@@ -2604,7 +2604,7 @@ 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
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 3e7ba8bce2ba..b1de695b826d 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1079,7 +1079,7 @@ static int __fragmentation_index(unsigned int order, struct contig_page_info *in
* 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;
--
2.27.0
On 06/17/20 at 06:03pm, Nitin Gupta wrote:
> 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 <[email protected]>
> ---
> include/linux/compaction.h | 4 ++--
> kernel/sysctl.c | 2 +-
> mm/compaction.c | 18 +++++++++---------
> mm/vmstat.c | 2 +-
> 4 files changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/compaction.h b/include/linux/compaction.h
> index 7a242d46454e..25a521d299c1 100644
> --- a/include/linux/compaction.h
> +++ b/include/linux/compaction.h
> @@ -85,13 +85,13 @@ static inline unsigned long compact_gap(unsigned int order)
>
> #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,
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 58b0a59c9769..40180cdde486 100644
> --- a/kernel/sysctl.c
> +++ b/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),
Patch looks good to me. Wondering why not using 'unsigned int' here,
just curious.
> .mode = 0644,
> .proc_handler = proc_dointvec_minmax,
> .extra1 = SYSCTL_ZERO,
> diff --git a/mm/compaction.c b/mm/compaction.c
> index ac2030814edb..45fd24a0ea0b 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)
> @@ -2604,7 +2604,7 @@ 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
> diff --git a/mm/vmstat.c b/mm/vmstat.c
> index 3e7ba8bce2ba..b1de695b826d 100644
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -1079,7 +1079,7 @@ static int __fragmentation_index(unsigned int order, struct contig_page_info *in
> * 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;
>
> --
> 2.27.0
>
>
On 6/18/20 6:41 AM, Baoquan He wrote:
> On 06/17/20 at 06:03pm, Nitin Gupta wrote:
>> 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 <[email protected]>
>> ---
>> include/linux/compaction.h | 4 ++--
>> kernel/sysctl.c | 2 +-
>> mm/compaction.c | 18 +++++++++---------
>> mm/vmstat.c | 2 +-
>> 4 files changed, 13 insertions(+), 13 deletions(-)
>>
>> diff --git a/include/linux/compaction.h b/include/linux/compaction.h
>> index 7a242d46454e..25a521d299c1 100644
>> --- a/include/linux/compaction.h
>> +++ b/include/linux/compaction.h
>> @@ -85,13 +85,13 @@ static inline unsigned long compact_gap(unsigned int order)
>>
>> #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,
>> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
>> index 58b0a59c9769..40180cdde486 100644
>> --- a/kernel/sysctl.c
>> +++ b/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),
>
> Patch looks good to me. Wondering why not using 'unsigned int' here,
> just curious.
>
It's just coding style preference. I see the same style used for many
other sysctls too (min_free_kbytes etc.).
Thanks,
Nitin
On 06/17/20 at 06:03pm, Nitin Gupta wrote:
> 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 <[email protected]>
Reviewed-by: Baoquan He <[email protected]>
> ---
> include/linux/compaction.h | 4 ++--
> kernel/sysctl.c | 2 +-
> mm/compaction.c | 18 +++++++++---------
> mm/vmstat.c | 2 +-
> 4 files changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/compaction.h b/include/linux/compaction.h
> index 7a242d46454e..25a521d299c1 100644
> --- a/include/linux/compaction.h
> +++ b/include/linux/compaction.h
> @@ -85,13 +85,13 @@ static inline unsigned long compact_gap(unsigned int order)
>
> #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,
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 58b0a59c9769..40180cdde486 100644
> --- a/kernel/sysctl.c
> +++ b/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,
> diff --git a/mm/compaction.c b/mm/compaction.c
> index ac2030814edb..45fd24a0ea0b 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)
> @@ -2604,7 +2604,7 @@ 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
> diff --git a/mm/vmstat.c b/mm/vmstat.c
> index 3e7ba8bce2ba..b1de695b826d 100644
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -1079,7 +1079,7 @@ static int __fragmentation_index(unsigned int order, struct contig_page_info *in
> * 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;
>
> --
> 2.27.0
>
>