Commit 972a3da3 authored by Wei Yang's avatar Wei Yang Committed by Linus Torvalds
Browse files

mm/hugetlb: count file_region to be added when regions_needed != NULL 



There are only two cases of function add_reservation_in_range()

    * count file_region and return the number in regions_needed
    * do the real list operation without counting

This means it is not necessary to have two parameters to classify these
two cases.

Just use regions_needed to separate them.

Signed-off-by: default avatarWei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarBaoquan He <bhe@redhat.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: https://lkml.kernel.org/r/20200831022351.20916-5-richard.weiyang@linux.alibaba.com


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d3ec7b6e

mm/hugetlb.c

+17 −16
Original line number Diff line number Diff line
@@ -321,16 +321,17 @@ static void coalesce_file_region(struct resv_map *resv, struct file_region *rg) 
	}

}



/* Must be called with resv->lock held. Calling this with count_only == true

 * will count the number of pages to be added but will not modify the linked

 * list. If regions_needed != NULL and count_only == true, then regions_needed

 * will indicate the number of file_regions needed in the cache to carry out to

 * add the regions for this range.

/*

 * Must be called with resv->lock held.

 *

 * Calling this with regions_needed != NULL will count the number of pages

 * to be added but will not modify the linked list. And regions_needed will

 * indicate the number of file_regions needed in the cache to carry out to add

 * the regions for this range.

 */

static long add_reservation_in_range(struct resv_map *resv, long f, long t,

				     struct hugetlb_cgroup *h_cg,

				     struct hstate *h, long *regions_needed,

				     bool count_only)

				     struct hstate *h, long *regions_needed)

{

	long add = 0;

	struct list_head *head = &resv->regions;
@@ -366,14 +367,14 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, 
		 */

		if (rg->from > last_accounted_offset) {

			add += rg->from - last_accounted_offset;

			if (!count_only) {

			if (!regions_needed) {

				nrg = get_file_region_entry_from_cache(

					resv, last_accounted_offset, rg->from);

				record_hugetlb_cgroup_uncharge_info(h_cg, h,

								    resv, nrg);

				list_add(&nrg->link, rg->link.prev);

				coalesce_file_region(resv, nrg);

			} else if (regions_needed)

			} else

				*regions_needed += 1;

		}
@@ -385,13 +386,13 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, 
	 */

	if (last_accounted_offset < t) {

		add += t - last_accounted_offset;

		if (!count_only) {

		if (!regions_needed) {

			nrg = get_file_region_entry_from_cache(

				resv, last_accounted_offset, t);

			record_hugetlb_cgroup_uncharge_info(h_cg, h, resv, nrg);

			list_add(&nrg->link, rg->link.prev);

			coalesce_file_region(resv, nrg);

		} else if (regions_needed)

		} else

			*regions_needed += 1;

	}
@@ -484,8 +485,8 @@ static long region_add(struct resv_map *resv, long f, long t, 
retry:



	/* Count how many regions are actually needed to execute this add. */

	add_reservation_in_range(resv, f, t, NULL, NULL, &actual_regions_needed,

				 true);

	add_reservation_in_range(resv, f, t, NULL, NULL,

				 &actual_regions_needed);



	/*

	 * Check for sufficient descriptors in the cache to accommodate
@@ -513,7 +514,7 @@ static long region_add(struct resv_map *resv, long f, long t, 
		goto retry;

	}



	add = add_reservation_in_range(resv, f, t, h_cg, h, NULL, false);

	add = add_reservation_in_range(resv, f, t, h_cg, h, NULL);



	resv->adds_in_progress -= in_regions_needed;
@@ -549,9 +550,9 @@ static long region_chg(struct resv_map *resv, long f, long t, 


	spin_lock(&resv->lock);



	/* Count how many hugepages in this range are NOT respresented. */

	/* Count how many hugepages in this range are NOT represented. */

	chg = add_reservation_in_range(resv, f, t, NULL, NULL,

				       out_regions_needed, true);

				       out_regions_needed);



	if (*out_regions_needed == 0)

		*out_regions_needed = 1;