Re: [PATCH -V8 13/16] hugetlb/cgroup: add hugetlb cgroup control files

[Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>]

(2012/06/12 19:58), Aneesh Kumar K.V wrote:
> Kamezawa Hiroyuki<kamezawa.hiroyu@jp.fujitsu.com>  writes:
> 
>> (2012/06/09 17:59), Aneesh Kumar K.V wrote:
>>> From: "Aneesh Kumar K.V"<aneesh.kumar@linux.vnet.ibm.com>
>>>
>>> Add the control files for hugetlb controller
>>>
>>> Signed-off-by: Aneesh Kumar K.V<aneesh.kumar@linux.vnet.ibm.com>
>>> ---
>>>    include/linux/hugetlb.h        |    5 ++
>>>    include/linux/hugetlb_cgroup.h |    6 ++
>>>    mm/hugetlb.c                   |    8 +++
>>>    mm/hugetlb_cgroup.c            |  130 ++++++++++++++++++++++++++++++++++++++++
>>>    4 files changed, 149 insertions(+)
>>>
>>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
>>> index 4aca057..9650bb1 100644
>>> --- a/include/linux/hugetlb.h
>>> +++ b/include/linux/hugetlb.h
>>> @@ -4,6 +4,7 @@
>>>    #include<linux/mm_types.h>
>>>    #include<linux/fs.h>
>>>    #include<linux/hugetlb_inline.h>
>>> +#include<linux/cgroup.h>
>>>
>>>    struct ctl_table;
>>>    struct user_struct;
>>> @@ -221,6 +222,10 @@ struct hstate {
>>>    	unsigned int nr_huge_pages_node[MAX_NUMNODES];
>>>    	unsigned int free_huge_pages_node[MAX_NUMNODES];
>>>    	unsigned int surplus_huge_pages_node[MAX_NUMNODES];
>>> +#ifdef CONFIG_CGROUP_HUGETLB_RES_CTLR
>>> +	/* cgroup control files */
>>> +	struct cftype cgroup_files[5];
>>> +#endif
>>>    	char name[HSTATE_NAME_LEN];
>>>    };
>>>
>>> diff --git a/include/linux/hugetlb_cgroup.h b/include/linux/hugetlb_cgroup.h
>>> index ceff1d5..ba4836f 100644
>>> --- a/include/linux/hugetlb_cgroup.h
>>> +++ b/include/linux/hugetlb_cgroup.h
>>> @@ -62,6 +62,7 @@ extern void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
>>>    					 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;
>>>    #else
>>>    static inline struct hugetlb_cgroup *hugetlb_cgroup_from_page(struct page *page)
>>>    {
>>> @@ -106,5 +107,10 @@ hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
>>>    {
>>>    	return;
>>>    }
>>> +
>>> +static inline int __init hugetlb_cgroup_file_init(int idx)
>>> +{
>>> +	return 0;
>>> +}
>>>    #endif  /* CONFIG_MEM_RES_CTLR_HUGETLB */
>>>    #endif
>>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>>> index 1ca2d8f..bf79131 100644
>>> --- a/mm/hugetlb.c
>>> +++ b/mm/hugetlb.c
>>> @@ -30,6 +30,7 @@
>>>    #include<linux/hugetlb.h>
>>>    #include<linux/hugetlb_cgroup.h>
>>>    #include<linux/node.h>
>>> +#include<linux/hugetlb_cgroup.h>
>>>    #include "internal.h"
>>>
>>>    const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
>>> @@ -1916,6 +1917,13 @@ void __init hugetlb_add_hstate(unsigned order)
>>>    	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>= 2)
>>> +		hugetlb_cgroup_file_init(hugetlb_max_hstate - 1);
>>>
>>
>> What happens at hugetlb module exit ? please see hugetlb_exit().
>>
>> BTW, module unload of hugetlbfs is restricted if hugetlb cgroup is mounted ??
>>
> 
> hugetlb is a binary config
> 
> config HUGETLBFS
> 	bool "HugeTLB file system support"
> 
> config HUGETLB_PAGE
> 	def_bool HUGETLBFS
> 
ok, so....hugetlb_exit() is never called ?

Thanks,
-Kame

--
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/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>