[PATCH] memcg: make threshold index in the right position
From: Sha Zhengju <hidden>
Date: 2012-02-03 02:50:30
Also in:
linux-mm
Subsystem:
control group - memory resource controller (memcg), memory management, the rest · Maintainers:
Johannes Weiner, Michal Hocko, Roman Gushchin, Shakeel Butt, Andrew Morton, Linus Torvalds
From: Sha Zhengju <redacted> Index current_threshold may point to threshold that just equal to usage after last call of __mem_cgroup_threshold. But after registering a new event, it will change (pointing to threshold just below usage). So make it consistent here. For example: now: threshold array: 3 [5] 7 9 (usage = 6, [index] = 5) next turn (after calling __mem_cgroup_threshold): threshold array: 3 5 [7] 9 (usage = 7, [index] = 7) after registering a new event (threshold = 10): threshold array: 3 [5] 7 9 10 (usage = 7, [index] = 5) Signed-off-by: Sha Zhengju <redacted> Acked-by: KAMEZAWA Hiroyuki <redacted> Reviewed-by: Kirill A. Shutemov <redacted> --- mm/memcontrol.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 22d94f5..95fc9f07 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c@@ -183,7 +183,7 @@ struct mem_cgroup_threshold { /* For threshold */ struct mem_cgroup_threshold_ary { - /* An array index points to threshold just below usage. */ + /* An array index points to threshold just below or equal to usage. */ int current_threshold; /* Size of entries[] */ unsigned int size;
@@ -4193,7 +4193,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) usage = mem_cgroup_usage(memcg, swap); /* - * current_threshold points to threshold just below usage. + * current_threshold points to threshold just below or equal to usage. * If it's not true, a threshold was crossed after last * call of __mem_cgroup_threshold(). */
@@ -4319,14 +4319,15 @@ static int mem_cgroup_usage_register_event(struct cgroup *cgrp, /* Find current threshold */ new->current_threshold = -1; for (i = 0; i < size; i++) { - if (new->entries[i].threshold < usage) { + if (new->entries[i].threshold <= usage) { /* * new->current_threshold will not be used until * rcu_assign_pointer(), so it's safe to increment * it here. */ ++new->current_threshold; - } + } else + break; } /* Free old spare buffer and save old primary buffer as spare */
--
1.7.4.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>