* [PATCH v3 1/3] mm: shmem: simplify the suitable huge orders validation for tmpfs
2024-07-22 5:43 [PATCH v3 0/3] Some cleanups for shmem Baolin Wang
@ 2024-07-22 5:43 ` Baolin Wang
2024-07-22 5:43 ` [PATCH v3 2/3] mm: shmem: rename shmem_is_huge() to shmem_huge_global_enabled() Baolin Wang
2024-07-22 5:43 ` [PATCH v3 3/3] mm: shmem: move shmem_huge_global_enabled() into shmem_allowable_huge_orders() Baolin Wang
2 siblings, 0 replies; 4+ messages in thread
From: Baolin Wang @ 2024-07-22 5:43 UTC (permalink / raw)
To: akpm, hughd
Cc: willy, david, 21cnbao, ryan.roberts, ziy, ioworker0, baolin.wang,
linux-mm, linux-kernel
Move the suitable huge orders validation into shmem_suitable_orders() for
tmpfs, which can reuse some code to simplify the logic.
In addition, we don't have special handling for the error code -E2BIG when
checking for conflicts with PMD sized THP in the pagecache for tmpfs, instead,
it will just fallback to order-0 allocations like this patch does, so this
simplification will not add functional changes.
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
---
mm/shmem.c | 39 +++++++++++++++------------------------
1 file changed, 15 insertions(+), 24 deletions(-)
diff --git a/mm/shmem.c b/mm/shmem.c
index f24dfbd387ba..db7e9808830f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1685,19 +1685,29 @@ static unsigned long shmem_suitable_orders(struct inode *inode, struct vm_fault
struct address_space *mapping, pgoff_t index,
unsigned long orders)
{
- struct vm_area_struct *vma = vmf->vma;
+ struct vm_area_struct *vma = vmf ? vmf->vma : NULL;
unsigned long pages;
int order;
- orders = thp_vma_suitable_orders(vma, vmf->address, orders);
- if (!orders)
- return 0;
+ if (vma) {
+ orders = thp_vma_suitable_orders(vma, vmf->address, orders);
+ if (!orders)
+ return 0;
+ }
/* Find the highest order that can add into the page cache */
order = highest_order(orders);
while (orders) {
pages = 1UL << order;
index = round_down(index, pages);
+ /*
+ * Check for conflict before waiting on a huge allocation.
+ * Conflict might be that a huge page has just been allocated
+ * and added to page cache by a racing thread, or that there
+ * is already at least one small page in the huge extent.
+ * Be careful to retry when appropriate, but not forever!
+ * Elsewhere -EEXIST would be the right code, but not here.
+ */
if (!xa_find(&mapping->i_pages, &index,
index + pages - 1, XA_PRESENT))
break;
@@ -1735,7 +1745,6 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf,
{
struct address_space *mapping = inode->i_mapping;
struct shmem_inode_info *info = SHMEM_I(inode);
- struct vm_area_struct *vma = vmf ? vmf->vma : NULL;
unsigned long suitable_orders = 0;
struct folio *folio = NULL;
long pages;
@@ -1745,26 +1754,8 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf,
orders = 0;
if (orders > 0) {
- if (vma && vma_is_anon_shmem(vma)) {
- suitable_orders = shmem_suitable_orders(inode, vmf,
+ suitable_orders = shmem_suitable_orders(inode, vmf,
mapping, index, orders);
- } else if (orders & BIT(HPAGE_PMD_ORDER)) {
- pages = HPAGE_PMD_NR;
- suitable_orders = BIT(HPAGE_PMD_ORDER);
- index = round_down(index, HPAGE_PMD_NR);
-
- /*
- * Check for conflict before waiting on a huge allocation.
- * Conflict might be that a huge page has just been allocated
- * and added to page cache by a racing thread, or that there
- * is already at least one small page in the huge extent.
- * Be careful to retry when appropriate, but not forever!
- * Elsewhere -EEXIST would be the right code, but not here.
- */
- if (xa_find(&mapping->i_pages, &index,
- index + HPAGE_PMD_NR - 1, XA_PRESENT))
- return ERR_PTR(-E2BIG);
- }
order = highest_order(suitable_orders);
while (suitable_orders) {
--
2.39.3
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH v3 2/3] mm: shmem: rename shmem_is_huge() to shmem_huge_global_enabled()
2024-07-22 5:43 [PATCH v3 0/3] Some cleanups for shmem Baolin Wang
2024-07-22 5:43 ` [PATCH v3 1/3] mm: shmem: simplify the suitable huge orders validation for tmpfs Baolin Wang
@ 2024-07-22 5:43 ` Baolin Wang
2024-07-22 5:43 ` [PATCH v3 3/3] mm: shmem: move shmem_huge_global_enabled() into shmem_allowable_huge_orders() Baolin Wang
2 siblings, 0 replies; 4+ messages in thread
From: Baolin Wang @ 2024-07-22 5:43 UTC (permalink / raw)
To: akpm, hughd
Cc: willy, david, 21cnbao, ryan.roberts, ziy, ioworker0, baolin.wang,
linux-mm, linux-kernel
The shmem_is_huge() is now used to check if the top-level huge page is enabled,
thus rename it to reflect its usage.
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
---
include/linux/shmem_fs.h | 9 +++++----
mm/huge_memory.c | 5 +++--
mm/shmem.c | 15 ++++++++-------
3 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 1d06b1e5408a..405ee8d3589a 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -111,14 +111,15 @@ extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
int shmem_unuse(unsigned int type);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-extern bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
- struct mm_struct *mm, unsigned long vm_flags);
+extern bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index, bool shmem_huge_force,
+ struct mm_struct *mm, unsigned long vm_flags);
unsigned long shmem_allowable_huge_orders(struct inode *inode,
struct vm_area_struct *vma, pgoff_t index,
bool global_huge);
#else
-static __always_inline bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
- struct mm_struct *mm, unsigned long vm_flags)
+static __always_inline bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct mm_struct *mm,
+ unsigned long vm_flags)
{
return false;
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index f4be468e06a4..e8388ea33f50 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -160,8 +160,9 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
* own flags.
*/
if (!in_pf && shmem_file(vma->vm_file)) {
- bool global_huge = shmem_is_huge(file_inode(vma->vm_file), vma->vm_pgoff,
- !enforce_sysfs, vma->vm_mm, vm_flags);
+ bool global_huge = shmem_huge_global_enabled(file_inode(vma->vm_file),
+ vma->vm_pgoff, !enforce_sysfs,
+ vma->vm_mm, vm_flags);
if (!vma_is_anon_shmem(vma))
return global_huge ? orders : 0;
diff --git a/mm/shmem.c b/mm/shmem.c
index db7e9808830f..1445dcd39b6f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -548,9 +548,9 @@ static bool shmem_confirm_swap(struct address_space *mapping,
static int shmem_huge __read_mostly = SHMEM_HUGE_NEVER;
-static bool __shmem_is_huge(struct inode *inode, pgoff_t index,
- bool shmem_huge_force, struct mm_struct *mm,
- unsigned long vm_flags)
+static bool __shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct mm_struct *mm,
+ unsigned long vm_flags)
{
loff_t i_size;
@@ -581,14 +581,15 @@ static bool __shmem_is_huge(struct inode *inode, pgoff_t index,
}
}
-bool shmem_is_huge(struct inode *inode, pgoff_t index,
+bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
bool shmem_huge_force, struct mm_struct *mm,
unsigned long vm_flags)
{
if (HPAGE_PMD_ORDER > MAX_PAGECACHE_ORDER)
return false;
- return __shmem_is_huge(inode, index, shmem_huge_force, mm, vm_flags);
+ return __shmem_huge_global_enabled(inode, index, shmem_huge_force,
+ mm, vm_flags);
}
#if defined(CONFIG_SYSFS)
@@ -1156,7 +1157,7 @@ static int shmem_getattr(struct mnt_idmap *idmap,
STATX_ATTR_NODUMP);
generic_fillattr(idmap, request_mask, inode, stat);
- if (shmem_is_huge(inode, 0, false, NULL, 0))
+ if (shmem_huge_global_enabled(inode, 0, false, NULL, 0))
stat->blksize = HPAGE_PMD_SIZE;
if (request_mask & STATX_BTIME) {
@@ -2153,7 +2154,7 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
return 0;
}
- huge = shmem_is_huge(inode, index, false, fault_mm,
+ huge = shmem_huge_global_enabled(inode, index, false, fault_mm,
vma ? vma->vm_flags : 0);
/* Find hugepage orders that are allowed for anonymous shmem. */
if (vma && vma_is_anon_shmem(vma))
--
2.39.3
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH v3 3/3] mm: shmem: move shmem_huge_global_enabled() into shmem_allowable_huge_orders()
2024-07-22 5:43 [PATCH v3 0/3] Some cleanups for shmem Baolin Wang
2024-07-22 5:43 ` [PATCH v3 1/3] mm: shmem: simplify the suitable huge orders validation for tmpfs Baolin Wang
2024-07-22 5:43 ` [PATCH v3 2/3] mm: shmem: rename shmem_is_huge() to shmem_huge_global_enabled() Baolin Wang
@ 2024-07-22 5:43 ` Baolin Wang
2 siblings, 0 replies; 4+ messages in thread
From: Baolin Wang @ 2024-07-22 5:43 UTC (permalink / raw)
To: akpm, hughd
Cc: willy, david, 21cnbao, ryan.roberts, ziy, ioworker0, baolin.wang,
linux-mm, linux-kernel
Move shmem_huge_global_enabled() into the shmem_allowable_huge_orders() function,
so that shmem_allowable_huge_orders() can also help to find the allowable huge
orders for tmpfs. Moreover the shmem_huge_global_enabled() can become static.
While we are at it, passing the vma instead of mm for shmem_huge_global_enabled()
makes code cleaner.
No functional changes.
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
---
include/linux/shmem_fs.h | 12 ++--------
mm/huge_memory.c | 12 +++-------
mm/shmem.c | 47 +++++++++++++++++++++++++---------------
3 files changed, 35 insertions(+), 36 deletions(-)
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 405ee8d3589a..1564d7d3ca61 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -111,21 +111,13 @@ extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
int shmem_unuse(unsigned int type);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-extern bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index, bool shmem_huge_force,
- struct mm_struct *mm, unsigned long vm_flags);
unsigned long shmem_allowable_huge_orders(struct inode *inode,
struct vm_area_struct *vma, pgoff_t index,
- bool global_huge);
+ bool shmem_huge_force);
#else
-static __always_inline bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
- bool shmem_huge_force, struct mm_struct *mm,
- unsigned long vm_flags)
-{
- return false;
-}
static inline unsigned long shmem_allowable_huge_orders(struct inode *inode,
struct vm_area_struct *vma, pgoff_t index,
- bool global_huge)
+ bool shmem_huge_force)
{
return 0;
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e8388ea33f50..e555fcdd19d4 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -159,16 +159,10 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
* Must be done before hugepage flags check since shmem has its
* own flags.
*/
- if (!in_pf && shmem_file(vma->vm_file)) {
- bool global_huge = shmem_huge_global_enabled(file_inode(vma->vm_file),
- vma->vm_pgoff, !enforce_sysfs,
- vma->vm_mm, vm_flags);
-
- if (!vma_is_anon_shmem(vma))
- return global_huge ? orders : 0;
+ if (!in_pf && shmem_file(vma->vm_file))
return shmem_allowable_huge_orders(file_inode(vma->vm_file),
- vma, vma->vm_pgoff, global_huge);
- }
+ vma, vma->vm_pgoff,
+ !enforce_sysfs);
if (!vma_is_anonymous(vma)) {
/*
diff --git a/mm/shmem.c b/mm/shmem.c
index 1445dcd39b6f..db8f74cac1a2 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -549,9 +549,10 @@ static bool shmem_confirm_swap(struct address_space *mapping,
static int shmem_huge __read_mostly = SHMEM_HUGE_NEVER;
static bool __shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
- bool shmem_huge_force, struct mm_struct *mm,
+ bool shmem_huge_force, struct vm_area_struct *vma,
unsigned long vm_flags)
{
+ struct mm_struct *mm = vma ? vma->vm_mm : NULL;
loff_t i_size;
if (!S_ISREG(inode->i_mode))
@@ -581,15 +582,15 @@ static bool __shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
}
}
-bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
- bool shmem_huge_force, struct mm_struct *mm,
+static bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct vm_area_struct *vma,
unsigned long vm_flags)
{
if (HPAGE_PMD_ORDER > MAX_PAGECACHE_ORDER)
return false;
return __shmem_huge_global_enabled(inode, index, shmem_huge_force,
- mm, vm_flags);
+ vma, vm_flags);
}
#if defined(CONFIG_SYSFS)
@@ -772,6 +773,13 @@ static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo,
{
return 0;
}
+
+static bool shmem_huge_global_enabled(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct vm_area_struct *vma,
+ unsigned long vm_flags)
+{
+ return false;
+}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
/*
@@ -1625,27 +1633,38 @@ static gfp_t limit_gfp_mask(gfp_t huge_gfp, gfp_t limit_gfp)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
unsigned long shmem_allowable_huge_orders(struct inode *inode,
struct vm_area_struct *vma, pgoff_t index,
- bool global_huge)
+ bool shmem_huge_force)
{
unsigned long mask = READ_ONCE(huge_shmem_orders_always);
unsigned long within_size_orders = READ_ONCE(huge_shmem_orders_within_size);
- unsigned long vm_flags = vma->vm_flags;
+ unsigned long vm_flags = vma ? vma->vm_flags : 0;
/*
* Check all the (large) orders below HPAGE_PMD_ORDER + 1 that
* are enabled for this vma.
*/
unsigned long orders = BIT(PMD_ORDER + 1) - 1;
+ bool global_huge;
loff_t i_size;
int order;
- if ((vm_flags & VM_NOHUGEPAGE) ||
- test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
+ if (vma && ((vm_flags & VM_NOHUGEPAGE) ||
+ test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)))
return 0;
/* If the hardware/firmware marked hugepage support disabled. */
if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED))
return 0;
+ global_huge = shmem_huge_global_enabled(inode, index, shmem_huge_force,
+ vma, vm_flags);
+ if (!vma || !vma_is_anon_shmem(vma)) {
+ /*
+ * For tmpfs, we now only support PMD sized THP if huge page
+ * is enabled, otherwise fallback to order 0.
+ */
+ return global_huge ? BIT(HPAGE_PMD_ORDER) : 0;
+ }
+
/*
* Following the 'deny' semantics of the top level, force the huge
* option off from all mounts.
@@ -2081,7 +2100,7 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
struct mm_struct *fault_mm;
struct folio *folio;
int error;
- bool alloced, huge;
+ bool alloced;
unsigned long orders = 0;
if (WARN_ON_ONCE(!shmem_mapping(inode->i_mapping)))
@@ -2154,14 +2173,8 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
return 0;
}
- huge = shmem_huge_global_enabled(inode, index, false, fault_mm,
- vma ? vma->vm_flags : 0);
- /* Find hugepage orders that are allowed for anonymous shmem. */
- if (vma && vma_is_anon_shmem(vma))
- orders = shmem_allowable_huge_orders(inode, vma, index, huge);
- else if (huge)
- orders = BIT(HPAGE_PMD_ORDER);
-
+ /* Find hugepage orders that are allowed for anonymous shmem and tmpfs. */
+ orders = shmem_allowable_huge_orders(inode, vma, index, false);
if (orders > 0) {
gfp_t huge_gfp;
--
2.39.3
^ permalink raw reply [flat|nested] 4+ messages in thread