Since commit 99cb0dbd47a1 ("mm,thp: add read-only THP support for
(non-shmem) FS"), read-only THP file mapping is supported. But it
forgot to add checking for it in transparent_hugepage_enabled().
To fix it, we add checking for read-only THP file mapping and also
introduce helper transhuge_vma_enabled() to check whether thp is
enabled for specified vma to reduce duplicated code. We rename
transparent_hugepage_enabled to transparent_hugepage_active to make
the code easier to follow as suggested by David Hildenbrand.
Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS")
Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
v3->v4:
collect Reviewed-by tag
define transhuge_vma_enabled next to transhuge_vma_suitable
---
fs/proc/task_mmu.c | 2 +-
include/linux/huge_mm.h | 57 +++++++++++++++++++++++++----------------
mm/huge_memory.c | 11 +++++++-
mm/khugepaged.c | 4 +--
mm/shmem.c | 3 +--
5 files changed, 48 insertions(+), 29 deletions(-)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index fc9784544b24..7389df326edd 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -832,7 +832,7 @@ static int show_smap(struct seq_file *m, void *v)
__show_smap(m, &mss, false);
seq_printf(m, "THPeligible: %d\n",
- transparent_hugepage_enabled(vma));
+ transparent_hugepage_active(vma));
if (arch_pkeys_enabled())
seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 0a526f211fec..7b7f7b52ccb8 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -115,9 +115,34 @@ extern struct kobj_attribute shmem_enabled_attr;
extern unsigned long transparent_hugepage_flags;
+static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
+ unsigned long haddr)
+{
+ /* Don't have to check pgoff for anonymous vma */
+ if (!vma_is_anonymous(vma)) {
+ if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
+ HPAGE_PMD_NR))
+ return false;
+ }
+
+ if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
+ return false;
+ return true;
+}
+
+static inline bool transhuge_vma_enabled(struct vm_area_struct *vma,
+ unsigned long vm_flags)
+{
+ /* Explicitly disabled through madvise. */
+ if ((vm_flags & VM_NOHUGEPAGE) ||
+ test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
+ return false;
+ return true;
+}
+
/*
* to be used on vmas which are known to support THP.
- * Use transparent_hugepage_enabled otherwise
+ * Use transparent_hugepage_active otherwise
*/
static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
{
@@ -128,15 +153,12 @@ static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_NEVER_DAX))
return false;
- if (vma->vm_flags & VM_NOHUGEPAGE)
+ if (!transhuge_vma_enabled(vma, vma->vm_flags))
return false;
if (vma_is_temporary_stack(vma))
return false;
- if (test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
- return false;
-
if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_FLAG))
return true;
@@ -150,22 +172,7 @@ static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
return false;
}
-bool transparent_hugepage_enabled(struct vm_area_struct *vma);
-
-static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
- unsigned long haddr)
-{
- /* Don't have to check pgoff for anonymous vma */
- if (!vma_is_anonymous(vma)) {
- if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
- HPAGE_PMD_NR))
- return false;
- }
-
- if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
- return false;
- return true;
-}
+bool transparent_hugepage_active(struct vm_area_struct *vma);
#define transparent_hugepage_use_zero_page() \
(transparent_hugepage_flags & \
@@ -351,7 +358,7 @@ static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
return false;
}
-static inline bool transparent_hugepage_enabled(struct vm_area_struct *vma)
+static inline bool transparent_hugepage_active(struct vm_area_struct *vma)
{
return false;
}
@@ -362,6 +369,12 @@ static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
return false;
}
+static inline bool transhuge_vma_enabled(struct vm_area_struct *vma,
+ unsigned long vm_flags)
+{
+ return false;
+}
+
static inline void prep_transhuge_page(struct page *page) {}
static inline bool is_transparent_hugepage(struct page *page)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 76ca1eb2a223..4f37867eed12 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -63,7 +63,14 @@ static struct shrinker deferred_split_shrinker;
static atomic_t huge_zero_refcount;
struct page *huge_zero_page __read_mostly;
-bool transparent_hugepage_enabled(struct vm_area_struct *vma)
+static inline bool file_thp_enabled(struct vm_area_struct *vma)
+{
+ return transhuge_vma_enabled(vma, vma->vm_flags) && vma->vm_file &&
+ !inode_is_open_for_write(vma->vm_file->f_inode) &&
+ (vma->vm_flags & VM_EXEC);
+}
+
+bool transparent_hugepage_active(struct vm_area_struct *vma)
{
/* The addr is used to check if the vma size fits */
unsigned long addr = (vma->vm_end & HPAGE_PMD_MASK) - HPAGE_PMD_SIZE;
@@ -74,6 +81,8 @@ bool transparent_hugepage_enabled(struct vm_area_struct *vma)
return __transparent_hugepage_enabled(vma);
if (vma_is_shmem(vma))
return shmem_huge_enabled(vma);
+ if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS))
+ return file_thp_enabled(vma);
return false;
}
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 6c0185fdd815..d97b20fad6e8 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -442,9 +442,7 @@ static inline int khugepaged_test_exit(struct mm_struct *mm)
static bool hugepage_vma_check(struct vm_area_struct *vma,
unsigned long vm_flags)
{
- /* Explicitly disabled through madvise. */
- if ((vm_flags & VM_NOHUGEPAGE) ||
- test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
+ if (!transhuge_vma_enabled(vma, vm_flags))
return false;
/* Enabled via shmem mount options or sysfs settings. */
diff --git a/mm/shmem.c b/mm/shmem.c
index a08cedefbfaa..1dcbec313c70 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -4032,8 +4032,7 @@ bool shmem_huge_enabled(struct vm_area_struct *vma)
loff_t i_size;
pgoff_t off;
- if ((vma->vm_flags & VM_NOHUGEPAGE) ||
- test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
+ if (!transhuge_vma_enabled(vma, vma->vm_flags))
return false;
if (shmem_huge == SHMEM_HUGE_FORCE)
return true;
--
2.23.0
