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>
This commit is contained in:
KAMEZAWA Hiroyuki 2010-03-10 15:22:30 -08:00 committed by Linus Torvalds
parent c62b1a3b31
commit 430e48631e

View File

@ -1424,8 +1424,7 @@ static int __cpuinit memcg_stock_cpu_callback(struct notifier_block *nb,
* 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 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
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 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
}
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 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
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 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc,
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 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
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 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
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 @@ int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
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 @@ one_by_one:
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;