[v2 5/6] mm: move allocation of gigantic hstates to the start of mm_core_init

From: Usama Arif
Date: Sun Jul 30 2023 - 11:16:24 EST


Whether the initialization of tail struct pages of a hugepage
happens or not will become dependent on the commandline
parameter hugetlb_free_vmemmap in the future. Hence,
hugetlb_hstate_alloc_pages needs to be after command line parameters
are parsed and the start of mm_core_init is a good point.

Signed-off-by: Usama Arif <usama.arif@xxxxxxxxxxxxx>
---
mm/hugetlb.c | 18 ++++++++++--------
mm/internal.h | 9 +++++++++
mm/mm_init.c | 6 ++++++
3 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 541c07b6d60f..bf60545496d7 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4400,14 +4400,6 @@ static int __init hugepages_setup(char *s)
}
}

- /*
- * Global state is always initialized later in hugetlb_init.
- * But we need to allocate gigantic hstates here early to still
- * use the bootmem allocator.
- */
- if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate))
- hugetlb_hstate_alloc_pages(parsed_hstate);
-
last_mhp = mhp;

return 1;
@@ -4419,6 +4411,16 @@ static int __init hugepages_setup(char *s)
}
__setup("hugepages=", hugepages_setup);

+void __init hugetlb_hstate_alloc_gigantic_pages(void)
+{
+ int i;
+
+ for (i = 0; i < HUGE_MAX_HSTATE; i++) {
+ if (hstate_is_gigantic(&hstates[i]))
+ hugetlb_hstate_alloc_pages(&hstates[i]);
+ }
+}
+
/*
* hugepagesz command line processing
* A specific huge page size can only be specified once with hugepagesz.
diff --git a/mm/internal.h b/mm/internal.h
index a7d9e980429a..692bb1136a39 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1102,4 +1102,13 @@ struct vma_prepare {
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
};
+
+#ifdef CONFIG_HUGETLBFS
+void __init hugetlb_hstate_alloc_gigantic_pages(void);
+#else
+static inline void __init hugetlb_hstate_alloc_gigantic_pages(void);
+{
+}
+#endif /* CONFIG_HUGETLBFS */
+
#endif /* __MM_INTERNAL_H */
diff --git a/mm/mm_init.c b/mm/mm_init.c
index a1963c3322af..f2751ccd7d99 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -26,6 +26,7 @@
#include <linux/pgtable.h>
#include <linux/swap.h>
#include <linux/cma.h>
+#include <linux/hugetlb.h>
#include "internal.h"
#include "slab.h"
#include "shuffle.h"
@@ -2768,6 +2769,11 @@ static void __init mem_init_print_info(void)
*/
void __init mm_core_init(void)
{
+ /*
+ * We need to allocate gigantic hstates here early to still use the bootmem
+ * allocator. Non gigantic hstates are initialized later in hugetlb_init.
+ */
+ hugetlb_hstate_alloc_gigantic_pages();
/* Initializations relying on SMP setup */
build_all_zonelists(NULL);
page_alloc_init_cpuhp();
--
2.25.1