Commit 077fcf116c8c ("mm/thp: allocate transparent hugepages on local
node") restructured alloc_hugepage_vma() with the intent of only
allocating transparent hugepages locally when there was not an effective
interleave mempolicy.
alloc_pages_exact_node() does not limit the allocation to the single
node, however, but rather prefers it. This is because __GFP_THISNODE is
not set which would cause the node-local nodemask to be passed. Without
it, only a nodemask that prefers the local node is passed.
Fix this by passing __GFP_THISNODE and falling back to small pages when
the allocation fails.
Commit 9f1b868a13ac ("mm: thp: khugepaged: add policy for finding target
node") suffers from a similar problem for khugepaged, which is also
fixed.
Fixes: 077fcf116c8c ("mm/thp: allocate transparent hugepages on local node")
Fixes: 9f1b868a13ac ("mm: thp: khugepaged: add policy for finding target node")
Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>
---
mm/huge_memory.c | 9 +++++++--
mm/mempolicy.c | 3 ++-
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2311,8 +2311,14 @@ static struct page
struct vm_area_struct *vma, unsigned long address,
int node)
{
+ gfp_t flags;
+
VM_BUG_ON_PAGE(*hpage, *hpage);
+ /* Only allocate from the target node */
+ flags = alloc_hugepage_gfpmask(khugepaged_defrag(), __GFP_OTHER_NODE) |
+ __GFP_THISNODE;
+
/*
* Before allocating the hugepage, release the mmap_sem read lock.
* The allocation can take potentially a long time if it involves
@@ -2321,8 +2327,7 @@ static struct page
*/
up_read(&mm->mmap_sem);
- *hpage = alloc_pages_exact_node(node, alloc_hugepage_gfpmask(
- khugepaged_defrag(), __GFP_OTHER_NODE), HPAGE_PMD_ORDER);
+ *hpage = alloc_pages_exact_node(node, flags, HPAGE_PMD_ORDER);
if (unlikely(!*hpage)) {
count_vm_event(THP_COLLAPSE_ALLOC_FAILED);
*hpage = ERR_PTR(-ENOMEM);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1985,7 +1985,8 @@ retry_cpuset:
nmask = policy_nodemask(gfp, pol);
if (!nmask || node_isset(node, *nmask)) {
mpol_cond_put(pol);
- page = alloc_pages_exact_node(node, gfp, order);
+ page = alloc_pages_exact_node(node,
+ gfp | __GFP_THISNODE, order);
goto out;
}
}
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