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-rw-r--r--mm/hugetlb.c116
1 files changed, 104 insertions, 12 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4fc590a1257d..899f6a81e77a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1437,7 +1437,76 @@ void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn)
dissolve_free_huge_page(pfn_to_page(pfn));
}
-static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
+/*
+ * There are 3 ways this can get called:
+ * 1. With vma+addr: we use the VMA's memory policy
+ * 2. With !vma, but nid=NUMA_NO_NODE: We try to allocate a huge
+ * page from any node, and let the buddy allocator itself figure
+ * it out.
+ * 3. With !vma, but nid!=NUMA_NO_NODE. We allocate a huge page
+ * strictly from 'nid'
+ */
+static struct page *__hugetlb_alloc_buddy_huge_page(struct hstate *h,
+ struct vm_area_struct *vma, unsigned long addr, int nid)
+{
+ int order = huge_page_order(h);
+ gfp_t gfp = htlb_alloc_mask(h)|__GFP_COMP|__GFP_REPEAT|__GFP_NOWARN;
+ unsigned int cpuset_mems_cookie;
+
+ /*
+ * We need a VMA to get a memory policy. If we do not
+ * have one, we use the 'nid' argument
+ */
+ if (!vma) {
+ /*
+ * If a specific node is requested, make sure to
+ * get memory from there, but only when a node
+ * is explicitly specified.
+ */
+ if (nid != NUMA_NO_NODE)
+ gfp |= __GFP_THISNODE;
+ /*
+ * Make sure to call something that can handle
+ * nid=NUMA_NO_NODE
+ */
+ return alloc_pages_node(nid, gfp, order);
+ }
+
+ /*
+ * OK, so we have a VMA. Fetch the mempolicy and try to
+ * allocate a huge page with it.
+ */
+ do {
+ struct page *page;
+ struct mempolicy *mpol;
+ struct zonelist *zl;
+ nodemask_t *nodemask;
+
+ cpuset_mems_cookie = read_mems_allowed_begin();
+ zl = huge_zonelist(vma, addr, gfp, &mpol, &nodemask);
+ mpol_cond_put(mpol);
+ page = __alloc_pages_nodemask(gfp, order, zl, nodemask);
+ if (page)
+ return page;
+ } while (read_mems_allowed_retry(cpuset_mems_cookie));
+
+ return NULL;
+}
+
+/*
+ * There are two ways to allocate a huge page:
+ * 1. When you have a VMA and an address (like a fault)
+ * 2. When you have no VMA (like when setting /proc/.../nr_hugepages)
+ *
+ * 'vma' and 'addr' are only for (1). 'nid' is always NUMA_NO_NODE in
+ * this case which signifies that the allocation should be done with
+ * respect for the VMA's memory policy.
+ *
+ * For (2), we ignore 'vma' and 'addr' and use 'nid' exclusively. This
+ * implies that memory policies will not be taken in to account.
+ */
+static struct page *__alloc_buddy_huge_page(struct hstate *h,
+ struct vm_area_struct *vma, unsigned long addr, int nid)
{
struct page *page;
unsigned int r_nid;
@@ -1446,6 +1515,15 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
return NULL;
/*
+ * Make sure that anyone specifying 'nid' is not also specifying a VMA.
+ * This makes sure the caller is picking _one_ of the modes with which
+ * we can call this function, not both.
+ */
+ if (vma || (addr != -1)) {
+ WARN_ON_ONCE(addr == -1);
+ WARN_ON_ONCE(nid != NUMA_NO_NODE);
+ }
+ /*
* Assume we will successfully allocate the surplus page to
* prevent racing processes from causing the surplus to exceed
* overcommit
@@ -1478,14 +1556,7 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
}
spin_unlock(&hugetlb_lock);
- if (nid == NUMA_NO_NODE)
- page = alloc_pages(htlb_alloc_mask(h)|__GFP_COMP|
- __GFP_REPEAT|__GFP_NOWARN,
- huge_page_order(h));
- else
- page = __alloc_pages_node(nid,
- htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE|
- __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h));
+ page = __hugetlb_alloc_buddy_huge_page(h, vma, addr, nid);
spin_lock(&hugetlb_lock);
if (page) {
@@ -1510,6 +1581,27 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
}
/*
+ * Allocate a huge page from 'nid'. Note, 'nid' may be
+ * NUMA_NO_NODE, which means that it may be allocated
+ * anywhere.
+ */
+struct page *__alloc_buddy_huge_page_no_mpol(struct hstate *h, int nid)
+{
+ unsigned long addr = -1;
+
+ return __alloc_buddy_huge_page(h, NULL, addr, nid);
+}
+
+/*
+ * Use the VMA's mpolicy to allocate a huge page from the buddy.
+ */
+struct page *__alloc_buddy_huge_page_with_mpol(struct hstate *h,
+ struct vm_area_struct *vma, unsigned long addr)
+{
+ return __alloc_buddy_huge_page(h, vma, addr, NUMA_NO_NODE);
+}
+
+/*
* This allocation function is useful in the context where vma is irrelevant.
* E.g. soft-offlining uses this function because it only cares physical
* address of error page.
@@ -1524,7 +1616,7 @@ struct page *alloc_huge_page_node(struct hstate *h, int nid)
spin_unlock(&hugetlb_lock);
if (!page)
- page = alloc_buddy_huge_page(h, nid);
+ page = __alloc_buddy_huge_page_no_mpol(h, nid);
return page;
}
@@ -1554,7 +1646,7 @@ static int gather_surplus_pages(struct hstate *h, int delta)
retry:
spin_unlock(&hugetlb_lock);
for (i = 0; i < needed; i++) {
- page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
+ page = __alloc_buddy_huge_page_no_mpol(h, NUMA_NO_NODE);
if (!page) {
alloc_ok = false;
break;
@@ -1787,7 +1879,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma,
page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg);
if (!page) {
spin_unlock(&hugetlb_lock);
- page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
+ page = __alloc_buddy_huge_page_with_mpol(h, vma, addr);
if (!page)
goto out_uncharge_cgroup;