[ 073/123] mm/hugetlb: create hugetlb cgroup file in hugetlb_init

Greg Kroah-Hartman
2013-01-09T20:40:22Z

From: Jianguo Wu <wujianguo@huawei.com>

commit 7179e7bf4592ac5a7b30257a7df6259ee81e51da upstream.

Build kernel with CONFIG_HUGETLBFS=y,CONFIG_HUGETLB_PAGE=y and
CONFIG_CGROUP_HUGETLB=y, then specify hugepagesz=xx boot option, system
will fail to boot.

This failure is caused by following code path:

setup_hugepagesz
hugetlb_add_hstate
hugetlb_cgroup_file_init
cgroup_add_cftypes
kzalloc <--slab is *not available* yet

For this path, slab is not available yet, so memory allocated will be
failed, and cause WARN_ON() in hugetlb_cgroup_file_init().

So I move hugetlb_cgroup_file_init() into hugetlb_init().

[akpm@linux-foundation.org: tweak coding-style, remove pointless __init on inlined function]
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
include/linux/hugetlb_cgroup.h | 5 ++---
mm/hugetlb.c | 11 +----------
mm/hugetlb_cgroup.c | 19 +++++++++++++++++--
3 files changed, 20 insertions(+), 15 deletions(-)

--- a/include/linux/hugetlb_cgroup.h
+++ b/include/linux/hugetlb_cgroup.h
@@ -62,7 +62,7 @@ extern void hugetlb_cgroup_uncharge_page
struct page *page);
extern void hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
struct hugetlb_cgroup *h_cg);
-extern int hugetlb_cgroup_file_init(int idx) __init;
+extern void hugetlb_cgroup_file_init(void) __init;
extern void hugetlb_cgroup_migrate(struct page *oldhpage,
struct page *newhpage);

@@ -111,9 +111,8 @@ hugetlb_cgroup_uncharge_cgroup(int idx,
return;
}

-static inline int __init hugetlb_cgroup_file_init(int idx)
+static inline void hugetlb_cgroup_file_init(void)
{
- return 0;
}

static inline void hugetlb_cgroup_migrate(struct page *oldhpage,
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1906,14 +1906,12 @@ static int __init hugetlb_init(void)
default_hstate.max_huge_pages = default_hstate_max_huge_pages;

hugetlb_init_hstates();
-
gather_bootmem_prealloc();
-
report_hugepages();

hugetlb_sysfs_init();
-
hugetlb_register_all_nodes();
+ hugetlb_cgroup_file_init();

return 0;
}
@@ -1943,13 +1941,6 @@ void __init hugetlb_add_hstate(unsigned
h->next_nid_to_free = first_node(node_states[N_HIGH_MEMORY]);
snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB",
huge_page_size(h)/1024);
- /*
- * Add cgroup control files only if the huge page consists
- * of more than two normal pages. This is because we use
- * page[2].lru.next for storing cgoup details.
- */
- if (order >= HUGETLB_CGROUP_MIN_ORDER)
- hugetlb_cgroup_file_init(hugetlb_max_hstate - 1);

parsed_hstate = h;
}
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -340,7 +340,7 @@ static char *mem_fmt(char *buf, int size
return buf;
}

-int __init hugetlb_cgroup_file_init(int idx)
+static void __init __hugetlb_cgroup_file_init(int idx)
{
char buf[32];
struct cftype *cft;
@@ -382,7 +382,22 @@ int __init hugetlb_cgroup_file_init(int

WARN_ON(cgroup_add_cftypes(&hugetlb_subsys, h->cgroup_files));

- return 0;
+ return;
+}
+
+void __init hugetlb_cgroup_file_init(void)
+{
+ struct hstate *h;
+
+ for_each_hstate(h) {
+ /*
+ * Add cgroup control files only if the huge page consists
+ * of more than two normal pages. This is because we use
+ * page[2].lru.next for storing cgroup details.
+ */
+ if (huge_page_order(h) >= HUGETLB_CGROUP_MIN_ORDER)
+ __hugetlb_cgroup_file_init(hstate_index(h));
+ }
}

/*