[PATCH 10/45] fs/proc: Create smaps_pud_range to handle PUD-mapped hugetlb vmas
From: Oscar Salvador
Date: Thu Jul 04 2024 - 00:33:53 EST
Normal THP cannot be PUD-mapped (besides devmap), but hugetlb can, so create
smaps_pud_range in order to handle PUD-mapped hugetlb vmas.
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
---
fs/proc/task_mmu.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 78d84d7e2353..3f3460ff03b0 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -912,6 +912,40 @@ static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
}
#endif
+#ifdef CONFIG_HUGETLB_PAGE
+static int smaps_pud_range(pud_t *pudp, unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ spinlock_t *ptl;
+ struct folio *folio;
+ struct vm_area_struct *vma = walk->vma;
+ struct mem_size_stats *mss = walk->private;
+
+ ptl = pud_huge_lock(pudp, vma);
+ if (!ptl)
+ return 0;
+
+ if (pud_present(*pudp)) {
+ folio = vm_normal_folio_pud(vma, addr, *pudp);
+ } else if (is_swap_pud(*pudp)) {
+ /* PUD-hugetlbs can have swap entries */
+ swp_entry_t swpent = pud_to_swp_entry(*pudp);
+
+ if (is_pfn_swap_entry(swpent))
+ folio = pfn_swap_entry_folio(swpent);
+ }
+
+ if (folio)
+ /* Only for now hugetlb pages can end up here */
+ mss_hugetlb_update(mss, folio, vma, (pte_t *)pudp);
+
+ spin_unlock(ptl);
+ return 0;
+}
+#else
+#define smaps_pud_range NULL
+#endif
+
static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
@@ -1061,12 +1095,14 @@ static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
#endif /* HUGETLB_PAGE */
static const struct mm_walk_ops smaps_walk_ops = {
+ .pud_entry = smaps_pud_range,
.pmd_entry = smaps_pte_range,
.hugetlb_entry = smaps_hugetlb_range,
.walk_lock = PGWALK_RDLOCK,
};
static const struct mm_walk_ops smaps_shmem_walk_ops = {
+ .pud_entry = smaps_pud_range,
.pmd_entry = smaps_pte_range,
.hugetlb_entry = smaps_hugetlb_range,
.pte_hole = smaps_pte_hole,
--
2.26.2