[PATCH v3 2/4] hugetlb: Fix hugepages_setup when deal with pernode

[Peng Liu <liupeng256@huawei.com>]

Hugepages can be specified to pernode since "hugetlbfs: extend
the definition of hugepages parameter to support node allocation",
but the following problem is observed.

Confusing behavior is observed when both 1G and 2M hugepage is set
after "numa=off".
 cmdline hugepage settings:
  hugepagesz=1G hugepages=0:3,1:3
  hugepagesz=2M hugepages=0:1024,1:1024
 results:
  HugeTLB registered 1.00 GiB page size, pre-allocated 0 pages
  HugeTLB registered 2.00 MiB page size, pre-allocated 1024 pages

Furthermore, confusing behavior can be also observed when an
invalid node behind a valid node. To fix this, never allocate any
typical hugepage when an invalid parameter is received.

Fixes: b5389086ad7b ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Signed-off-by: Peng Liu <liupeng256@huawei.com>
---
 mm/hugetlb.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5b5a2a5a742f..1930b6341f7e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4116,6 +4116,20 @@ bool __init __weak hugetlb_node_alloc_supported(void)
 {
 	return true;
 }
+
+static void __init hugepages_clear_pages_in_node(void)
+{
+	if (!hugetlb_max_hstate) {
+		default_hstate_max_huge_pages = 0;
+		memset(default_hugepages_in_node, 0,
+			MAX_NUMNODES * sizeof(unsigned int));
+	} else {
+		parsed_hstate->max_huge_pages = 0;
+		memset(parsed_hstate->max_huge_pages_node, 0,
+			MAX_NUMNODES * sizeof(unsigned int));
+	}
+}
+
 /*
  * hugepages command line processing
  * hugepages normally follows a valid hugepagsz or default_hugepagsz
@@ -4203,6 +4217,7 @@ static int __init hugepages_setup(char *s)
 
 invalid:
 	pr_warn("HugeTLB: Invalid hugepages parameter %s\n", p);
+	hugepages_clear_pages_in_node();
 	return 0;
 }
 __setup("hugepages=", hugepages_setup);
-- 
2.18.0.huawei.25