memcg: update threshold and softlimit at commit
Presently, move_task does "batched" precharge. Because res_counter or
css's refcnt are not-scalable jobs for memcg, try_charge_().. tend to be
done in batched manner if allowed.
Now, softlimit and threshold check their event counter in try_charge, but
the charge is not a per-page event. And event counter is not updated at
charge(). Moreover, precharge doesn't pass "page" to try_charge() and
softlimit tree will be never updated until uncharge() causes an event."
So the best place to check the event counter is commit_charge(). This is
per-page event by its nature. This patch move checks to there.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 9c9dfcf..006fe14 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1424,8 +1424,7 @@
* oom-killer can be invoked.
*/
static int __mem_cgroup_try_charge(struct mm_struct *mm,
- gfp_t gfp_mask, struct mem_cgroup **memcg,
- bool oom, struct page *page)
+ gfp_t gfp_mask, struct mem_cgroup **memcg, bool oom)
{
struct mem_cgroup *mem, *mem_over_limit;
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
@@ -1463,7 +1462,7 @@
unsigned long flags = 0;
if (consume_stock(mem))
- goto charged;
+ goto done;
ret = res_counter_charge(&mem->res, csize, &fail_res);
if (likely(!ret)) {
@@ -1558,16 +1557,7 @@
}
if (csize > PAGE_SIZE)
refill_stock(mem, csize - PAGE_SIZE);
-charged:
- /*
- * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
- * if they exceeds softlimit.
- */
- if (page && mem_cgroup_soft_limit_check(mem))
- mem_cgroup_update_tree(mem, page);
done:
- if (mem_cgroup_threshold_check(mem))
- mem_cgroup_threshold(mem);
return 0;
nomem:
css_put(&mem->css);
@@ -1691,6 +1681,16 @@
mem_cgroup_charge_statistics(mem, pc, true);
unlock_page_cgroup(pc);
+ /*
+ * "charge_statistics" updated event counter. Then, check it.
+ * 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);
+
}
/**
@@ -1788,7 +1788,7 @@
goto put;
parent = mem_cgroup_from_cont(pcg);
- ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, page);
+ ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false);
if (ret || !parent)
goto put_back;
@@ -1824,7 +1824,7 @@
prefetchw(pc);
mem = memcg;
- ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true, page);
+ ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true);
if (ret || !mem)
return ret;
@@ -1944,14 +1944,14 @@
if (!mem)
goto charge_cur_mm;
*ptr = mem;
- ret = __mem_cgroup_try_charge(NULL, mask, ptr, true, page);
+ ret = __mem_cgroup_try_charge(NULL, mask, ptr, true);
/* drop extra refcnt from tryget */
css_put(&mem->css);
return ret;
charge_cur_mm:
if (unlikely(!mm))
mm = &init_mm;
- return __mem_cgroup_try_charge(mm, mask, ptr, true, page);
+ return __mem_cgroup_try_charge(mm, mask, ptr, true);
}
static void
@@ -2340,8 +2340,7 @@
unlock_page_cgroup(pc);
if (mem) {
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false,
- page);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
css_put(&mem->css);
}
*ptr = mem;
@@ -3872,8 +3871,7 @@
batch_count = PRECHARGE_COUNT_AT_ONCE;
cond_resched();
}
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem,
- false, NULL);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, &mem, false);
if (ret || !mem)
/* mem_cgroup_clear_mc() will do uncharge later */
return -ENOMEM;