From: Oscar Salvador <osalvador@suse.de>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: David Hildenbrand <david@redhat.com>,
Muchun Song <muchun.song@linux.dev>, Peter Xu <peterx@redhat.com>,
Gavin Guo <gavinguo@igalia.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Oscar Salvador <osalvador@suse.de>
Subject: [PATCH v2 3/5] mm,hugetlb: Rename anon_rmap to new_anon_folio and make it boolean
Date: Fri, 20 Jun 2025 14:30:12 +0200 [thread overview]
Message-ID: <20250620123014.29748-4-osalvador@suse.de> (raw)
In-Reply-To: <20250620123014.29748-1-osalvador@suse.de>
anon_rmap is used to determine whether the new allocated folio is anonymous.
Rename it to something more meaningul like new_anon_folio and make it boolean,
as we use it like that.
While we are at it, drop 'new_pagecache_folio' as 'new_anon_folio' is enough to
check whether we need to restore the consumed reservation.
Signed-off-by: Oscar Salvador <osalvador@suse.de>
---
mm/hugetlb.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 1a5f713c1e4c..57bb8b2dce21 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6427,17 +6427,16 @@ static bool hugetlb_pte_stable(struct hstate *h, struct mm_struct *mm, unsigned
static vm_fault_t hugetlb_no_page(struct address_space *mapping,
struct vm_fault *vmf)
{
+ u32 hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
+ bool new_folio, new_anon_folio = false;
struct vm_area_struct *vma = vmf->vma;
struct mm_struct *mm = vma->vm_mm;
struct hstate *h = hstate_vma(vma);
vm_fault_t ret = VM_FAULT_SIGBUS;
- int anon_rmap = 0;
- unsigned long size;
+ bool folio_locked = true;
struct folio *folio;
+ unsigned long size;
pte_t new_pte;
- bool new_folio, new_pagecache_folio = false;
- u32 hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
- bool folio_locked = true;
/*
* Currently, we are forced to kill the process in the event the
@@ -6518,6 +6517,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
folio_zero_user(folio, vmf->real_address);
__folio_mark_uptodate(folio);
new_folio = true;
+ new_anon_folio = !(vma->vm_flags & VM_MAYSHARE);
if (vma->vm_flags & VM_MAYSHARE) {
int err = hugetlb_add_to_page_cache(folio, mapping,
@@ -6536,10 +6536,8 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
ret = VM_FAULT_SIGBUS;
goto out;
}
- new_pagecache_folio = true;
} else {
folio_lock(folio);
- anon_rmap = 1;
}
} else {
/*
@@ -6588,7 +6586,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
if (!pte_same(huge_ptep_get(mm, vmf->address, vmf->pte), vmf->orig_pte))
goto backout;
- if (anon_rmap)
+ if (new_anon_folio)
hugetlb_add_new_anon_rmap(folio, vma, vmf->address);
else
hugetlb_add_file_rmap(folio);
@@ -6604,7 +6602,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* No need to lock file folios. See comment in hugetlb_fault() */
- if (!anon_rmap) {
+ if (!new_anon_folio) {
folio_locked = false;
folio_unlock(folio);
}
@@ -6640,7 +6638,8 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping,
backout:
spin_unlock(vmf->ptl);
backout_unlocked:
- if (new_folio && !new_pagecache_folio)
+ /* We only need to restore reservations for private mappings */
+ if (new_folio && new_anon_folio)
restore_reserve_on_error(h, vma, vmf->address, folio);
if (folio_locked)
--
2.50.0
next prev parent reply other threads:[~2025-06-20 12:30 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-20 12:30 [PATCH v2 0/5] Misc rework on hugetlb faulting path Oscar Salvador
2025-06-20 12:30 ` [PATCH v2 1/5] mm,hugetlb: Change mechanism to detect a COW on private mapping Oscar Salvador
2025-06-23 14:09 ` David Hildenbrand
2025-06-25 7:49 ` Oscar Salvador
2025-06-25 10:13 ` David Hildenbrand
2025-06-20 12:30 ` [PATCH v2 2/5] mm,hugetlb: Sort out folio locking in the faulting path Oscar Salvador
2025-06-23 14:11 ` David Hildenbrand
2025-06-25 7:47 ` Oscar Salvador
2025-06-25 20:47 ` Oscar Salvador
2025-06-20 12:30 ` Oscar Salvador [this message]
2025-06-20 14:28 ` [PATCH v2 3/5] mm,hugetlb: Rename anon_rmap to new_anon_folio and make it boolean Oscar Salvador
2025-06-23 14:13 ` David Hildenbrand
2025-06-25 7:43 ` Oscar Salvador
2025-06-20 12:30 ` [PATCH v2 4/5] mm,hugetlb: Drop obsolete comment about non-present pte and second faults Oscar Salvador
2025-06-20 12:30 ` [PATCH v2 5/5] mm,hugetlb: Drop unlikelys from hugetlb_fault Oscar Salvador
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