hugetlb: multiple hstates for multiple page sizes
Add basic support for more than one hstate in hugetlbfs. This is the key
to supporting multiple hugetlbfs page sizes at once.
- Rather than a single hstate, we now have an array, with an iterator
- default_hstate continues to be the struct hstate which we use by default
- Add functions for architectures to register new hstates
[akpm@linux-foundation.org: coding-style fixes]
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0d8153e..82378d4 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -22,12 +22,19 @@
#include "internal.h"
const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
-unsigned long max_huge_pages;
-unsigned long sysctl_overcommit_huge_pages;
static gfp_t htlb_alloc_mask = GFP_HIGHUSER;
unsigned long hugepages_treat_as_movable;
-struct hstate default_hstate;
+static int max_hstate;
+unsigned int default_hstate_idx;
+struct hstate hstates[HUGE_MAX_HSTATE];
+
+/* for command line parsing */
+static struct hstate * __initdata parsed_hstate;
+static unsigned long __initdata default_hstate_max_huge_pages;
+
+#define for_each_hstate(h) \
+ for ((h) = hstates; (h) < &hstates[max_hstate]; (h)++)
/*
* Protects updates to hugepage_freelists, nr_huge_pages, and free_huge_pages
@@ -454,13 +461,24 @@
__free_pages(page, huge_page_order(h));
}
+struct hstate *size_to_hstate(unsigned long size)
+{
+ struct hstate *h;
+
+ for_each_hstate(h) {
+ if (huge_page_size(h) == size)
+ return h;
+ }
+ return NULL;
+}
+
static void free_huge_page(struct page *page)
{
/*
* Can't pass hstate in here because it is called from the
* compound page destructor.
*/
- struct hstate *h = &default_hstate;
+ struct hstate *h = page_hstate(page);
int nid = page_to_nid(page);
struct address_space *mapping;
@@ -887,39 +905,94 @@
return page;
}
-static int __init hugetlb_init(void)
+static void __init hugetlb_init_one_hstate(struct hstate *h)
{
unsigned long i;
- struct hstate *h = &default_hstate;
-
- if (HPAGE_SHIFT == 0)
- return 0;
-
- if (!h->order) {
- h->order = HPAGE_SHIFT - PAGE_SHIFT;
- h->mask = HPAGE_MASK;
- }
for (i = 0; i < MAX_NUMNODES; ++i)
INIT_LIST_HEAD(&h->hugepage_freelists[i]);
h->hugetlb_next_nid = first_node(node_online_map);
- for (i = 0; i < max_huge_pages; ++i) {
+ for (i = 0; i < h->max_huge_pages; ++i) {
if (!alloc_fresh_huge_page(h))
break;
}
- max_huge_pages = h->free_huge_pages = h->nr_huge_pages = i;
- printk(KERN_INFO "Total HugeTLB memory allocated, %ld\n",
- h->free_huge_pages);
+ h->max_huge_pages = h->free_huge_pages = h->nr_huge_pages = i;
+}
+
+static void __init hugetlb_init_hstates(void)
+{
+ struct hstate *h;
+
+ for_each_hstate(h) {
+ hugetlb_init_one_hstate(h);
+ }
+}
+
+static void __init report_hugepages(void)
+{
+ struct hstate *h;
+
+ for_each_hstate(h) {
+ printk(KERN_INFO "Total HugeTLB memory allocated, "
+ "%ld %dMB pages\n",
+ h->free_huge_pages,
+ 1 << (h->order + PAGE_SHIFT - 20));
+ }
+}
+
+static int __init hugetlb_init(void)
+{
+ BUILD_BUG_ON(HPAGE_SHIFT == 0);
+
+ if (!size_to_hstate(HPAGE_SIZE)) {
+ hugetlb_add_hstate(HUGETLB_PAGE_ORDER);
+ parsed_hstate->max_huge_pages = default_hstate_max_huge_pages;
+ }
+ default_hstate_idx = size_to_hstate(HPAGE_SIZE) - hstates;
+
+ hugetlb_init_hstates();
+
+ report_hugepages();
+
return 0;
}
module_init(hugetlb_init);
+/* Should be called on processing a hugepagesz=... option */
+void __init hugetlb_add_hstate(unsigned order)
+{
+ struct hstate *h;
+ if (size_to_hstate(PAGE_SIZE << order)) {
+ printk(KERN_WARNING "hugepagesz= specified twice, ignoring\n");
+ return;
+ }
+ BUG_ON(max_hstate >= HUGE_MAX_HSTATE);
+ BUG_ON(order == 0);
+ h = &hstates[max_hstate++];
+ h->order = order;
+ h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
+ hugetlb_init_one_hstate(h);
+ parsed_hstate = h;
+}
+
static int __init hugetlb_setup(char *s)
{
- if (sscanf(s, "%lu", &max_huge_pages) <= 0)
- max_huge_pages = 0;
+ unsigned long *mhp;
+
+ /*
+ * !max_hstate means we haven't parsed a hugepagesz= parameter yet,
+ * so this hugepages= parameter goes to the "default hstate".
+ */
+ if (!max_hstate)
+ mhp = &default_hstate_max_huge_pages;
+ else
+ mhp = &parsed_hstate->max_huge_pages;
+
+ if (sscanf(s, "%lu", mhp) <= 0)
+ *mhp = 0;
+
return 1;
}
__setup("hugepages=", hugetlb_setup);
@@ -950,7 +1023,7 @@
if (PageHighMem(page))
continue;
list_del(&page->lru);
- update_and_free_page(page);
+ update_and_free_page(h, page);
h->free_huge_pages--;
h->free_huge_pages_node[page_to_nid(page)]--;
}
@@ -963,10 +1036,9 @@
#endif
#define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages)
-static unsigned long set_max_huge_pages(unsigned long count)
+static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count)
{
unsigned long min_count, ret;
- struct hstate *h = &default_hstate;
/*
* Increase the pool size
@@ -1037,8 +1109,19 @@
struct file *file, void __user *buffer,
size_t *length, loff_t *ppos)
{
+ struct hstate *h = &default_hstate;
+ unsigned long tmp;
+
+ if (!write)
+ tmp = h->max_huge_pages;
+
+ table->data = &tmp;
+ table->maxlen = sizeof(unsigned long);
proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
- max_huge_pages = set_max_huge_pages(max_huge_pages);
+
+ if (write)
+ h->max_huge_pages = set_max_huge_pages(h, tmp);
+
return 0;
}
@@ -1059,10 +1142,21 @@
size_t *length, loff_t *ppos)
{
struct hstate *h = &default_hstate;
+ unsigned long tmp;
+
+ if (!write)
+ tmp = h->nr_overcommit_huge_pages;
+
+ table->data = &tmp;
+ table->maxlen = sizeof(unsigned long);
proc_doulongvec_minmax(table, write, file, buffer, length, ppos);
- spin_lock(&hugetlb_lock);
- h->nr_overcommit_huge_pages = sysctl_overcommit_huge_pages;
- spin_unlock(&hugetlb_lock);
+
+ if (write) {
+ spin_lock(&hugetlb_lock);
+ h->nr_overcommit_huge_pages = tmp;
+ spin_unlock(&hugetlb_lock);
+ }
+
return 0;
}