mm/hugetlb: unify clearing of RestoreReserve for private pages

A trivial cleanup to move clearing of RestoreReserve into adding anon rmap
of private hugetlb mappings.  It matches with the shared mappings where we
only clear the bit when adding into page cache, rather than spreading it
around the code paths.

Link: https://lkml.kernel.org/r/20221020193832.776173-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0af18c1..d11e921 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4775,7 +4775,6 @@ hugetlb_install_page(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr
        hugepage_add_new_anon_rmap(new_page, vma, addr);
        set_huge_pte_at(vma->vm_mm, addr, ptep, make_huge_pte(vma, new_page, 1));
        hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm);
-       ClearHPageRestoreReserve(new_page);
        SetHPageMigratable(new_page);
 }
 
@@ -5438,8 +5437,6 @@ retry_avoidcopy:
        spin_lock(ptl);
        ptep = huge_pte_offset(mm, haddr, huge_page_size(h));
        if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) {
-               ClearHPageRestoreReserve(new_page);
-
                /* Break COW or unshare */
                huge_ptep_clear_flush(vma, haddr, ptep);
                mmu_notifier_invalidate_range(mm, range.start, range.end);
@@ -5734,10 +5731,9 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
        if (!pte_same(huge_ptep_get(ptep), old_pte))
                goto backout;
 
-       if (anon_rmap) {
-               ClearHPageRestoreReserve(page);
+       if (anon_rmap)
                hugepage_add_new_anon_rmap(page, vma, haddr);
-       } else
+       else
                page_dup_file_rmap(page, true);
        new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE)
                                && (vma->vm_flags & VM_SHARED)));
@@ -6120,12 +6116,10 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
        if (!huge_pte_none_mostly(huge_ptep_get(dst_pte)))
                goto out_release_unlock;
 
-       if (page_in_pagecache) {
+       if (page_in_pagecache)
                page_dup_file_rmap(page, true);
-       } else {
-               ClearHPageRestoreReserve(page);
+       else
                hugepage_add_new_anon_rmap(page, dst_vma, dst_addr);
-       }
 
        /*
         * For either: (1) CONTINUE on a non-shared VMA, or (2) UFFDIO_COPY

diff --git a/mm/rmap.c b/mm/rmap.c
index 9bba65b..3b2d18b 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -2571,7 +2571,7 @@ void hugepage_add_new_anon_rmap(struct page *page,
        BUG_ON(address < vma->vm_start || address >= vma->vm_end);
        atomic_set(compound_mapcount_ptr(page), 0);
        atomic_set(compound_pincount_ptr(page), 0);
-
+       ClearHPageRestoreReserve(page);
        __page_set_anon_rmap(page, vma, address, 1);
 }
 #endif /* CONFIG_HUGETLB_PAGE */