Kamezawa Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> writes: > (2012/06/09 17:59), Aneesh Kumar K.V wrote: >> From: "Aneesh Kumar K.V"<aneesh.kumar@xxxxxxxxxxxxxxxxxx> >> >> This patch add support for cgroup removal. If we don't have parent >> cgroup, the charges are moved to root cgroup. >> >> Signed-off-by: Aneesh Kumar K.V<aneesh.kumar@xxxxxxxxxxxxxxxxxx> > > I'm sorry if already pointed out.... > >> --- >> mm/hugetlb_cgroup.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 79 insertions(+), 2 deletions(-) >> >> diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c >> index 48efd5a..9458fe3 100644 >> --- a/mm/hugetlb_cgroup.c >> +++ b/mm/hugetlb_cgroup.c >> @@ -99,10 +99,87 @@ static void hugetlb_cgroup_destroy(struct cgroup *cgroup) >> kfree(h_cgroup); >> } >> >> + >> +static int hugetlb_cgroup_move_parent(int idx, struct cgroup *cgroup, >> + struct page *page) >> +{ >> + int csize; >> + struct res_counter *counter; >> + struct res_counter *fail_res; >> + struct hugetlb_cgroup *page_hcg; >> + struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_cgroup(cgroup); >> + struct hugetlb_cgroup *parent = parent_hugetlb_cgroup(cgroup); >> + >> + if (!get_page_unless_zero(page)) >> + goto out; > > It seems this doesn't necessary...this is under hugetlb_lock(). already updated. > >> + >> + page_hcg = hugetlb_cgroup_from_page(page); >> + /* >> + * We can have pages in active list without any cgroup >> + * ie, hugepage with less than 3 pages. We can safely >> + * ignore those pages. >> + */ >> + if (!page_hcg || page_hcg != h_cg) >> + goto err_out; >> + >> + csize = PAGE_SIZE<< compound_order(page); >> + if (!parent) { >> + parent = root_h_cgroup; >> + /* root has no limit */ >> + res_counter_charge_nofail(&parent->hugepage[idx], >> + csize,&fail_res); > ^^^ > space ? I don't have code this way locally, may be a mail client error ? > >> + } >> + counter =&h_cg->hugepage[idx]; >> + res_counter_uncharge_until(counter, counter->parent, csize); >> + >> + set_hugetlb_cgroup(page, parent); >> +err_out: >> + put_page(page); >> +out: >> + return 0; >> +} >> + >> +/* >> + * Force the hugetlb cgroup to empty the hugetlb resources by moving them to >> + * the parent cgroup. >> + */ >> static int hugetlb_cgroup_pre_destroy(struct cgroup *cgroup) >> { >> - /* We will add the cgroup removal support in later patches */ >> - return -EBUSY; >> + struct hstate *h; >> + struct page *page; >> + int ret = 0, idx = 0; >> + >> + do { >> + if (cgroup_task_count(cgroup) || >> + !list_empty(&cgroup->children)) { >> + ret = -EBUSY; >> + goto out; >> + } Is this check going to moved to higher levels ? Do we still need this. Or will that happen when pred_destroy becomes void ? > >> + /* >> + * If the task doing the cgroup_rmdir got a signal >> + * we don't really need to loop till the hugetlb resource >> + * usage become zero. >> + */ >> + if (signal_pending(current)) { >> + ret = -EINTR; >> + goto out; >> + } > > I'll post a patch to remove this check from memcg because memcg's rmdir > always succeed now. So, could you remove this ? Will drop this > > >> + for_each_hstate(h) { >> + spin_lock(&hugetlb_lock); >> + list_for_each_entry(page,&h->hugepage_activelist, lru) { >> + ret = hugetlb_cgroup_move_parent(idx, cgroup, page); >> + if (ret) { > > When 'ret' should be !0 ? > If hugetlb_cgroup_move_parent() always returns 0, the check will not be necessary. > I will make this void funciton. -aneesh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>