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-rw-r--r--mm/memcontrol.c86
1 files changed, 41 insertions, 45 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 006fe14..f9ae4b4 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -63,8 +63,15 @@ static int really_do_swap_account __initdata = 1; /* for remember boot option*/
#define do_swap_account (0)
#endif
-#define SOFTLIMIT_EVENTS_THRESH (1000)
-#define THRESHOLDS_EVENTS_THRESH (100)
+/*
+ * Per memcg event counter is incremented at every pagein/pageout. This counter
+ * is used for trigger some periodic events. This is straightforward and better
+ * than using jiffies etc. to handle periodic memcg event.
+ *
+ * These values will be used as !((event) & ((1 <<(thresh)) - 1))
+ */
+#define THRESHOLDS_EVENTS_THRESH (7) /* once in 128 */
+#define SOFTLIMIT_EVENTS_THRESH (10) /* once in 1024 */
/*
* Statistics for memory cgroup.
@@ -79,10 +86,7 @@ enum mem_cgroup_stat_index {
MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */
MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */
MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */
- MEM_CGROUP_STAT_SOFTLIMIT, /* decrements on each page in/out.
- used by soft limit implementation */
- MEM_CGROUP_STAT_THRESHOLDS, /* decrements on each page in/out.
- used by threshold implementation */
+ MEM_CGROUP_EVENTS, /* incremented at every pagein/pageout */
MEM_CGROUP_STAT_NSTATS,
};
@@ -154,7 +158,6 @@ struct mem_cgroup_threshold_ary {
struct mem_cgroup_threshold entries[0];
};
-static bool mem_cgroup_threshold_check(struct mem_cgroup *mem);
static void mem_cgroup_threshold(struct mem_cgroup *mem);
/*
@@ -392,19 +395,6 @@ mem_cgroup_remove_exceeded(struct mem_cgroup *mem,
spin_unlock(&mctz->lock);
}
-static bool mem_cgroup_soft_limit_check(struct mem_cgroup *mem)
-{
- bool ret = false;
- s64 val;
-
- val = this_cpu_read(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT]);
- if (unlikely(val < 0)) {
- this_cpu_write(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT],
- SOFTLIMIT_EVENTS_THRESH);
- ret = true;
- }
- return ret;
-}
static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page)
{
@@ -542,8 +532,7 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *mem,
__this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGIN_COUNT]);
else
__this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGOUT_COUNT]);
- __this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT]);
- __this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS]);
+ __this_cpu_inc(mem->stat->count[MEM_CGROUP_EVENTS]);
preempt_enable();
}
@@ -563,6 +552,29 @@ static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem,
return total;
}
+static bool __memcg_event_check(struct mem_cgroup *mem, int event_mask_shift)
+{
+ s64 val;
+
+ val = this_cpu_read(mem->stat->count[MEM_CGROUP_EVENTS]);
+
+ return !(val & ((1 << event_mask_shift) - 1));
+}
+
+/*
+ * Check events in order.
+ *
+ */
+static void memcg_check_events(struct mem_cgroup *mem, struct page *page)
+{
+ /* threshold event is triggered in finer grain than soft limit */
+ if (unlikely(__memcg_event_check(mem, THRESHOLDS_EVENTS_THRESH))) {
+ mem_cgroup_threshold(mem);
+ if (unlikely(__memcg_event_check(mem, SOFTLIMIT_EVENTS_THRESH)))
+ mem_cgroup_update_tree(mem, page);
+ }
+}
+
static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
{
return container_of(cgroup_subsys_state(cont,
@@ -1686,11 +1698,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
* Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
* if they exceeds softlimit.
*/
- if (mem_cgroup_soft_limit_check(mem))
- mem_cgroup_update_tree(mem, pc->page);
- if (mem_cgroup_threshold_check(mem))
- mem_cgroup_threshold(mem);
-
+ memcg_check_events(mem, pc->page);
}
/**
@@ -1760,6 +1768,11 @@ static int mem_cgroup_move_account(struct page_cgroup *pc,
ret = 0;
}
unlock_page_cgroup(pc);
+ /*
+ * check events
+ */
+ memcg_check_events(to, pc->page);
+ memcg_check_events(from, pc->page);
return ret;
}
@@ -2128,10 +2141,7 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
mz = page_cgroup_zoneinfo(pc);
unlock_page_cgroup(pc);
- if (mem_cgroup_soft_limit_check(mem))
- mem_cgroup_update_tree(mem, page);
- if (mem_cgroup_threshold_check(mem))
- mem_cgroup_threshold(mem);
+ memcg_check_events(mem, page);
/* at swapout, this memcg will be accessed to record to swap */
if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
css_put(&mem->css);
@@ -3215,20 +3225,6 @@ static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft,
return 0;
}
-static bool mem_cgroup_threshold_check(struct mem_cgroup *mem)
-{
- bool ret = false;
- s64 val;
-
- val = this_cpu_read(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS]);
- if (unlikely(val < 0)) {
- this_cpu_write(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS],
- THRESHOLDS_EVENTS_THRESH);
- ret = true;
- }
- return ret;
-}
-
static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
{
struct mem_cgroup_threshold_ary *t;
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