diff options
| author | Mel Gorman <mel@csn.ul.ie> | 2011-01-14 00:45:43 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-14 02:32:31 +0100 |
| commit | b44129b30652c8771db2265939bb8b463724043d (patch) | |
| tree | d5b669ff4faea020b03e894706f49d5d1ae56907 /mm/vmstat.c | |
| parent | mm: page allocator: adjust the per-cpu counter threshold when memory is low (diff) | |
| download | linux-b44129b30652c8771db2265939bb8b463724043d.tar.xz linux-b44129b30652c8771db2265939bb8b463724043d.zip | |
mm: vmstat: use a single setter function and callback for adjusting percpu thresholds
reduce_pgdat_percpu_threshold() and restore_pgdat_percpu_threshold() exist
to adjust the per-cpu vmstat thresholds while kswapd is awake to avoid
errors due to counter drift. The functions duplicate some code so this
patch replaces them with a single set_pgdat_percpu_threshold() that takes
a callback function to calculate the desired threshold as a parameter.
[akpm@linux-foundation.org: readability tweak]
[kosaki.motohiro@jp.fujitsu.com: set_pgdat_percpu_threshold(): don't use for_each_online_cpu]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | mm/vmstat.c | 36 |
1 files changed, 7 insertions, 29 deletions
diff --git a/mm/vmstat.c b/mm/vmstat.c index bc0f095791b4..751a65e00aac 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -83,7 +83,7 @@ EXPORT_SYMBOL(vm_stat); #ifdef CONFIG_SMP -static int calculate_pressure_threshold(struct zone *zone) +int calculate_pressure_threshold(struct zone *zone) { int threshold; int watermark_distance; @@ -107,7 +107,7 @@ static int calculate_pressure_threshold(struct zone *zone) return threshold; } -static int calculate_threshold(struct zone *zone) +int calculate_normal_threshold(struct zone *zone) { int threshold; int mem; /* memory in 128 MB units */ @@ -166,7 +166,7 @@ static void refresh_zone_stat_thresholds(void) for_each_populated_zone(zone) { unsigned long max_drift, tolerate_drift; - threshold = calculate_threshold(zone); + threshold = calculate_normal_threshold(zone); for_each_online_cpu(cpu) per_cpu_ptr(zone->pageset, cpu)->stat_threshold @@ -185,46 +185,24 @@ static void refresh_zone_stat_thresholds(void) } } -void reduce_pgdat_percpu_threshold(pg_data_t *pgdat) +void set_pgdat_percpu_threshold(pg_data_t *pgdat, + int (*calculate_pressure)(struct zone *)) { struct zone *zone; int cpu; int threshold; int i; - get_online_cpus(); - for (i = 0; i < pgdat->nr_zones; i++) { - zone = &pgdat->node_zones[i]; - if (!zone->percpu_drift_mark) - continue; - - threshold = calculate_pressure_threshold(zone); - for_each_online_cpu(cpu) - per_cpu_ptr(zone->pageset, cpu)->stat_threshold - = threshold; - } - put_online_cpus(); -} - -void restore_pgdat_percpu_threshold(pg_data_t *pgdat) -{ - struct zone *zone; - int cpu; - int threshold; - int i; - - get_online_cpus(); for (i = 0; i < pgdat->nr_zones; i++) { zone = &pgdat->node_zones[i]; if (!zone->percpu_drift_mark) continue; - threshold = calculate_threshold(zone); - for_each_online_cpu(cpu) + threshold = (*calculate_pressure)(zone); + for_each_possible_cpu(cpu) per_cpu_ptr(zone->pageset, cpu)->stat_threshold = threshold; } - put_online_cpus(); } /* |