Commit 7ca02d0a authored by Mike Kravetz's avatar Mike Kravetz Committed by Linus Torvalds
Browse files

hugetlbfs: accept subpool min_size mount option and setup accordingly 



Make 'min_size=<value>' be an option when mounting a hugetlbfs.  This
option takes the same value as the 'size' option.  min_size can be
specified without specifying size.  If both are specified, min_size must
be less that or equal to size else the mount will fail.  If min_size is
specified, then at mount time an attempt is made to reserve min_size
pages.  If the reservation fails, the mount fails.  At umount time, the
reserved pages are released.

Signed-off-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 1c5ecae3

fs/hugetlbfs/inode.c

+71 −19
Original line number Diff line number Diff line
@@ -47,9 +47,10 @@ struct hugetlbfs_config { 
	kuid_t   uid;

	kgid_t   gid;

	umode_t mode;

	long	nr_blocks;

	long	max_hpages;

	long	nr_inodes;

	struct hstate *hstate;

	long    min_hpages;

};



struct hugetlbfs_inode_info {
@@ -67,7 +68,7 @@ int sysctl_hugetlb_shm_group; 
enum {

	Opt_size, Opt_nr_inodes,

	Opt_mode, Opt_uid, Opt_gid,

	Opt_pagesize,

	Opt_pagesize, Opt_min_size,

	Opt_err,

};
@@ -78,6 +79,7 @@ static const match_table_t tokens = { 
	{Opt_uid,	"uid=%u"},

	{Opt_gid,	"gid=%u"},

	{Opt_pagesize,	"pagesize=%s"},

	{Opt_min_size,	"min_size=%s"},

	{Opt_err,	NULL},

};
@@ -754,14 +756,38 @@ static const struct super_operations hugetlbfs_ops = { 
	.show_options	= generic_show_options,

};



enum { NO_SIZE, SIZE_STD, SIZE_PERCENT };



/*

 * Convert size option passed from command line to number of huge pages

 * in the pool specified by hstate.  Size option could be in bytes

 * (val_type == SIZE_STD) or percentage of the pool (val_type == SIZE_PERCENT).

 */

static long long

hugetlbfs_size_to_hpages(struct hstate *h, unsigned long long size_opt,

								int val_type)

{

	if (val_type == NO_SIZE)

		return -1;



	if (val_type == SIZE_PERCENT) {

		size_opt <<= huge_page_shift(h);

		size_opt *= h->max_huge_pages;

		do_div(size_opt, 100);

	}



	size_opt >>= huge_page_shift(h);

	return size_opt;

}



static int

hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)

{

	char *p, *rest;

	substring_t args[MAX_OPT_ARGS];

	int option;

	unsigned long long size = 0;

	enum { NO_SIZE, SIZE_STD, SIZE_PERCENT } setsize = NO_SIZE;

	unsigned long long max_size_opt = 0, min_size_opt = 0;

	int max_val_type = NO_SIZE, min_val_type = NO_SIZE;



	if (!options)

		return 0;
@@ -799,10 +825,10 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) 
			/* memparse() will accept a K/M/G without a digit */

			if (!isdigit(*args[0].from))

				goto bad_val;

			size = memparse(args[0].from, &rest);

			setsize = SIZE_STD;

			max_size_opt = memparse(args[0].from, &rest);

			max_val_type = SIZE_STD;

			if (*rest == '%')

				setsize = SIZE_PERCENT;

				max_val_type = SIZE_PERCENT;

			break;

		}
@@ -825,6 +851,17 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) 
			break;

		}



		case Opt_min_size: {

			/* memparse() will accept a K/M/G without a digit */

			if (!isdigit(*args[0].from))

				goto bad_val;

			min_size_opt = memparse(args[0].from, &rest);

			min_val_type = SIZE_STD;

			if (*rest == '%')

				min_val_type = SIZE_PERCENT;

			break;

		}



		default:

			pr_err("Bad mount option: \"%s\"\n", p);

			return -EINVAL;
@@ -832,15 +869,22 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) 
		}

	}



	/* Do size after hstate is set up */

	if (setsize > NO_SIZE) {

		struct hstate *h = pconfig->hstate;

		if (setsize == SIZE_PERCENT) {

			size <<= huge_page_shift(h);

			size *= h->max_huge_pages;

			do_div(size, 100);

		}

		pconfig->nr_blocks = (size >> huge_page_shift(h));

	/*

	 * Use huge page pool size (in hstate) to convert the size

	 * options to number of huge pages.  If NO_SIZE, -1 is returned.

	 */

	pconfig->max_hpages = hugetlbfs_size_to_hpages(pconfig->hstate,

						max_size_opt, max_val_type);

	pconfig->min_hpages = hugetlbfs_size_to_hpages(pconfig->hstate,

						min_size_opt, min_val_type);



	/*

	 * If max_size was specified, then min_size must be smaller

	 */

	if (max_val_type > NO_SIZE &&

	    pconfig->min_hpages > pconfig->max_hpages) {

		pr_err("minimum size can not be greater than maximum size\n");

		return -EINVAL;

	}



	return 0;
@@ -859,12 +903,13 @@ hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) 


	save_mount_options(sb, data);



	config.nr_blocks = -1; /* No limit on size by default */

	config.max_hpages = -1; /* No limit on size by default */

	config.nr_inodes = -1; /* No limit on number of inodes by default */

	config.uid = current_fsuid();

	config.gid = current_fsgid();

	config.mode = 0755;

	config.hstate = &default_hstate;

	config.min_hpages = -1; /* No default minimum size */

	ret = hugetlbfs_parse_options(data, &config);

	if (ret)

		return ret;
@@ -878,8 +923,15 @@ hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) 
	sbinfo->max_inodes = config.nr_inodes;

	sbinfo->free_inodes = config.nr_inodes;

	sbinfo->spool = NULL;

	if (config.nr_blocks != -1) {

		sbinfo->spool = hugepage_new_subpool(config.nr_blocks);

	/*

	 * Allocate and initialize subpool if maximum or minimum size is

	 * specified.  Any needed reservations (for minimim size) are taken

	 * taken when the subpool is created.

	 */

	if (config.max_hpages != -1 || config.min_hpages != -1) {

		sbinfo->spool = hugepage_new_subpool(config.hstate,

							config.max_hpages,

							config.min_hpages);

		if (!sbinfo->spool)

			goto out_free;

	}

include/linux/hugetlb.h

+2 −1
Original line number Diff line number Diff line
@@ -44,7 +44,8 @@ extern int hugetlb_max_hstate __read_mostly; 
#define for_each_hstate(h) \

	for ((h) = hstates; (h) < &hstates[hugetlb_max_hstate]; (h)++)



struct hugepage_subpool *hugepage_new_subpool(long nr_blocks);

struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages,

						long min_hpages);

void hugepage_put_subpool(struct hugepage_subpool *spool);



void reset_vma_resv_huge_pages(struct vm_area_struct *vma);

mm/hugetlb.c

+21 −4
Original line number Diff line number Diff line
@@ -61,6 +61,9 @@ DEFINE_SPINLOCK(hugetlb_lock); 
static int num_fault_mutexes;

static struct mutex *htlb_fault_mutex_table ____cacheline_aligned_in_smp;



/* Forward declaration */

static int hugetlb_acct_memory(struct hstate *h, long delta);



static inline void unlock_or_release_subpool(struct hugepage_subpool *spool)

{

	bool free = (spool->count == 0) && (spool->used_hpages == 0);
@@ -68,12 +71,18 @@ static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) 
	spin_unlock(&spool->lock);



	/* If no pages are used, and no other handles to the subpool

	 * remain, free the subpool the subpool remain */

	if (free)

	 * remain, give up any reservations mased on minimum size and

	 * free the subpool */

	if (free) {

		if (spool->min_hpages != -1)

			hugetlb_acct_memory(spool->hstate,

						-spool->min_hpages);

		kfree(spool);

	}

}



struct hugepage_subpool *hugepage_new_subpool(long nr_blocks)

struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages,

						long min_hpages)

{

	struct hugepage_subpool *spool;
@@ -83,7 +92,15 @@ struct hugepage_subpool *hugepage_new_subpool(long nr_blocks) 


	spin_lock_init(&spool->lock);

	spool->count = 1;

	spool->max_hpages = nr_blocks;

	spool->max_hpages = max_hpages;

	spool->hstate = h;

	spool->min_hpages = min_hpages;



	if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) {

		kfree(spool);

		return NULL;

	}

	spool->rsv_hpages = min_hpages;



	return spool;

}

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