aboutsummaryrefslogtreecommitdiffstats
path: root/mm/hugetlb.c
diff options
context:
space:
mode:
authorLee Schermerhorn <lee.schermerhorn@hp.com>2009-09-22 00:01:23 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-22 14:17:26 (GMT)
commit685f345708096ed21078aa44a6f4a6e6d1d1b580 (patch)
tree9ba51e5721d4749317be33623a382940c0299bec /mm/hugetlb.c
parente8c5c8249878fb6564125680a1d15e06adbd5639 (diff)
hugetlb: use free_pool_huge_page() to return unused surplus pages
Use the [modified] free_pool_huge_page() function to return unused surplus pages. This will help keep huge pages balanced across nodes between freeing of unused surplus pages and freeing of persistent huge pages [from set_max_huge_pages] by using the same node id "cursor". It also eliminates some code duplication. Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Nishanth Aravamudan <nacc@us.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Adam Litke <agl@us.ibm.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Eric Whitney <eric.whitney@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c57
1 files changed, 24 insertions, 33 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 38dab55..f10cc27 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -687,7 +687,7 @@ static int hstate_next_node_to_free(struct hstate *h)
* balanced over allowed nodes.
* Called with hugetlb_lock locked.
*/
-static int free_pool_huge_page(struct hstate *h)
+static int free_pool_huge_page(struct hstate *h, bool acct_surplus)
{
int start_nid;
int next_nid;
@@ -697,13 +697,22 @@ static int free_pool_huge_page(struct hstate *h)
next_nid = start_nid;
do {
- if (!list_empty(&h->hugepage_freelists[next_nid])) {
+ /*
+ * If we're returning unused surplus pages, only examine
+ * nodes with surplus pages.
+ */
+ if ((!acct_surplus || h->surplus_huge_pages_node[next_nid]) &&
+ !list_empty(&h->hugepage_freelists[next_nid])) {
struct page *page =
list_entry(h->hugepage_freelists[next_nid].next,
struct page, lru);
list_del(&page->lru);
h->free_huge_pages--;
h->free_huge_pages_node[next_nid]--;
+ if (acct_surplus) {
+ h->surplus_huge_pages--;
+ h->surplus_huge_pages_node[next_nid]--;
+ }
update_and_free_page(h, page);
ret = 1;
}
@@ -884,22 +893,13 @@ free:
* When releasing a hugetlb pool reservation, any surplus pages that were
* allocated to satisfy the reservation must be explicitly freed if they were
* never used.
+ * Called with hugetlb_lock held.
*/
static void return_unused_surplus_pages(struct hstate *h,
unsigned long unused_resv_pages)
{
- static int nid = -1;
- struct page *page;
unsigned long nr_pages;
- /*
- * We want to release as many surplus pages as possible, spread
- * evenly across all nodes. Iterate across all nodes until we
- * can no longer free unreserved surplus pages. This occurs when
- * the nodes with surplus pages have no free pages.
- */
- unsigned long remaining_iterations = nr_online_nodes;
-
/* Uncommit the reservation */
h->resv_huge_pages -= unused_resv_pages;
@@ -909,26 +909,17 @@ static void return_unused_surplus_pages(struct hstate *h,
nr_pages = min(unused_resv_pages, h->surplus_huge_pages);
- while (remaining_iterations-- && nr_pages) {
- nid = next_node(nid, node_online_map);
- if (nid == MAX_NUMNODES)
- nid = first_node(node_online_map);
-
- if (!h->surplus_huge_pages_node[nid])
- continue;
-
- if (!list_empty(&h->hugepage_freelists[nid])) {
- page = list_entry(h->hugepage_freelists[nid].next,
- struct page, lru);
- list_del(&page->lru);
- update_and_free_page(h, page);
- h->free_huge_pages--;
- h->free_huge_pages_node[nid]--;
- h->surplus_huge_pages--;
- h->surplus_huge_pages_node[nid]--;
- nr_pages--;
- remaining_iterations = nr_online_nodes;
- }
+ /*
+ * We want to release as many surplus pages as possible, spread
+ * evenly across all nodes. Iterate across all nodes until we
+ * can no longer free unreserved surplus pages. This occurs when
+ * the nodes with surplus pages have no free pages.
+ * free_pool_huge_page() will balance the the frees across the
+ * on-line nodes for us and will handle the hstate accounting.
+ */
+ while (nr_pages--) {
+ if (!free_pool_huge_page(h, 1))
+ break;
}
}
@@ -1268,7 +1259,7 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count)
min_count = max(count, min_count);
try_to_free_low(h, min_count);
while (min_count < persistent_huge_pages(h)) {
- if (!free_pool_huge_page(h))
+ if (!free_pool_huge_page(h, 0))
break;
}
while (count < persistent_huge_pages(h)) {

Privacy Policy