* [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP
@ 2021-04-07 3:05 yanfei.xu
2021-04-07 3:05 ` [PATCH v2 1/2] mm: khugepaged: use macro to align addresses yanfei.xu
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: yanfei.xu @ 2021-04-07 3:05 UTC (permalink / raw)
To: shy828301; +Cc: linux-mm, linux-kernel
From: Yanfei Xu <yanfei.xu@windriver.com>
v1-->v2:
1.correct the wrong location where the goto jump to.
2.keep the cond_resched() dropped in v1 still there.
Thanks for Yang's review.
Yanfei Xu (2):
mm: khugepaged: use macro to align addresses
mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas
mm/khugepaged.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
--
2.27.0
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v2 1/2] mm: khugepaged: use macro to align addresses
2021-04-07 3:05 [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP yanfei.xu
@ 2021-04-07 3:05 ` yanfei.xu
2021-04-07 21:40 ` Yang Shi
2021-04-07 3:05 ` [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas yanfei.xu
2021-04-14 2:14 ` [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP Xu, Yanfei
2 siblings, 1 reply; 8+ messages in thread
From: yanfei.xu @ 2021-04-07 3:05 UTC (permalink / raw)
To: shy828301; +Cc: linux-mm, linux-kernel
From: Yanfei Xu <yanfei.xu@windriver.com>
We could use macro to deal with the addresses which need to be aligned
to improve readability of codes.
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
---
mm/khugepaged.c | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index a7d6cb912b05..a6012b9259a2 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -517,8 +517,8 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
if (!hugepage_vma_check(vma, vm_flags))
return 0;
- hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
- hend = vma->vm_end & HPAGE_PMD_MASK;
+ hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
+ hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
if (hstart < hend)
return khugepaged_enter(vma, vm_flags);
return 0;
@@ -979,8 +979,8 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
if (!vma)
return SCAN_VMA_NULL;
- hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
- hend = vma->vm_end & HPAGE_PMD_MASK;
+ hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
+ hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
if (address < hstart || address + HPAGE_PMD_SIZE > hend)
return SCAN_ADDRESS_RANGE;
if (!hugepage_vma_check(vma, vma->vm_flags))
@@ -1070,7 +1070,7 @@ static void collapse_huge_page(struct mm_struct *mm,
struct mmu_notifier_range range;
gfp_t gfp;
- VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+ VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
/* Only allocate from the target node */
gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
@@ -1235,7 +1235,7 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
int node = NUMA_NO_NODE, unmapped = 0;
bool writable = false;
- VM_BUG_ON(address & ~HPAGE_PMD_MASK);
+ VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
pmd = mm_find_pmd(mm, address);
if (!pmd) {
@@ -1414,7 +1414,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
{
struct mm_slot *mm_slot;
- VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
+ VM_BUG_ON(!IS_ALIGNED(addr, HPAGE_PMD_SIZE));
spin_lock(&khugepaged_mm_lock);
mm_slot = get_mm_slot(mm);
@@ -1437,7 +1437,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
*/
void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
{
- unsigned long haddr = addr & HPAGE_PMD_MASK;
+ unsigned long haddr = ALIGN_DOWN(addr, HPAGE_PMD_SIZE);
struct vm_area_struct *vma = find_vma(mm, haddr);
struct page *hpage;
pte_t *start_pte, *pte;
@@ -1584,7 +1584,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
if (vma->anon_vma)
continue;
addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
- if (addr & ~HPAGE_PMD_MASK)
+ if (!IS_ALIGNED(addr, HPAGE_PMD_SIZE))
continue;
if (vma->vm_end < addr + HPAGE_PMD_SIZE)
continue;
@@ -2070,7 +2070,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
{
struct mm_slot *mm_slot;
struct mm_struct *mm;
- struct vm_area_struct *vma;
+ struct vm_area_struct *vma = NULL;
int progress = 0;
VM_BUG_ON(!pages);
@@ -2092,7 +2092,6 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
* Don't wait for semaphore (to avoid long wait times). Just move to
* the next mm on the list.
*/
- vma = NULL;
if (unlikely(!mmap_read_trylock(mm)))
goto breakouterloop_mmap_lock;
if (likely(!khugepaged_test_exit(mm)))
@@ -2112,15 +2111,15 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
progress++;
continue;
}
- hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
- hend = vma->vm_end & HPAGE_PMD_MASK;
+ hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
+ hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
if (hstart >= hend)
goto skip;
if (khugepaged_scan.address > hend)
goto skip;
if (khugepaged_scan.address < hstart)
khugepaged_scan.address = hstart;
- VM_BUG_ON(khugepaged_scan.address & ~HPAGE_PMD_MASK);
+ VM_BUG_ON(!IS_ALIGNED(khugepaged_scan.address, HPAGE_PMD_SIZE));
if (shmem_file(vma->vm_file) && !shmem_huge_enabled(vma))
goto skip;
--
2.27.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas
2021-04-07 3:05 [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP yanfei.xu
2021-04-07 3:05 ` [PATCH v2 1/2] mm: khugepaged: use macro to align addresses yanfei.xu
@ 2021-04-07 3:05 ` yanfei.xu
2021-04-07 21:40 ` Yang Shi
2021-04-14 2:14 ` [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP Xu, Yanfei
2 siblings, 1 reply; 8+ messages in thread
From: yanfei.xu @ 2021-04-07 3:05 UTC (permalink / raw)
To: shy828301; +Cc: linux-mm, linux-kernel
From: Yanfei Xu <yanfei.xu@windriver.com>
We could check MMF_DISABLE_THP ahead of iterating over all of vma.
Otherwise if some mm_struct contain a large number of vma, there will
be amounts meaningless cpu cycles cost.
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
---
mm/khugepaged.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index a6012b9259a2..f4ad25a7db55 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2094,6 +2094,8 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
*/
if (unlikely(!mmap_read_trylock(mm)))
goto breakouterloop_mmap_lock;
+ if (test_bit(MMF_DISABLE_THP, &mm->flags))
+ goto breakouterloop;
if (likely(!khugepaged_test_exit(mm)))
vma = find_vma(mm, khugepaged_scan.address);
--
2.27.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v2 1/2] mm: khugepaged: use macro to align addresses
2021-04-07 3:05 ` [PATCH v2 1/2] mm: khugepaged: use macro to align addresses yanfei.xu
@ 2021-04-07 21:40 ` Yang Shi
0 siblings, 0 replies; 8+ messages in thread
From: Yang Shi @ 2021-04-07 21:40 UTC (permalink / raw)
To: yanfei.xu; +Cc: Linux MM, Linux Kernel Mailing List
On Tue, Apr 6, 2021 at 8:06 PM <yanfei.xu@windriver.com> wrote:
>
> From: Yanfei Xu <yanfei.xu@windriver.com>
>
> We could use macro to deal with the addresses which need to be aligned
> to improve readability of codes.
Reviewed-by: Yang Shi <shy828301@gmail.com>
>
> Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
> ---
> mm/khugepaged.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index a7d6cb912b05..a6012b9259a2 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -517,8 +517,8 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
> if (!hugepage_vma_check(vma, vm_flags))
> return 0;
>
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (hstart < hend)
> return khugepaged_enter(vma, vm_flags);
> return 0;
> @@ -979,8 +979,8 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
> if (!vma)
> return SCAN_VMA_NULL;
>
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (address < hstart || address + HPAGE_PMD_SIZE > hend)
> return SCAN_ADDRESS_RANGE;
> if (!hugepage_vma_check(vma, vma->vm_flags))
> @@ -1070,7 +1070,7 @@ static void collapse_huge_page(struct mm_struct *mm,
> struct mmu_notifier_range range;
> gfp_t gfp;
>
> - VM_BUG_ON(address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
>
> /* Only allocate from the target node */
> gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
> @@ -1235,7 +1235,7 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
> int node = NUMA_NO_NODE, unmapped = 0;
> bool writable = false;
>
> - VM_BUG_ON(address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
>
> pmd = mm_find_pmd(mm, address);
> if (!pmd) {
> @@ -1414,7 +1414,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
> {
> struct mm_slot *mm_slot;
>
> - VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(addr, HPAGE_PMD_SIZE));
>
> spin_lock(&khugepaged_mm_lock);
> mm_slot = get_mm_slot(mm);
> @@ -1437,7 +1437,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
> */
> void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
> {
> - unsigned long haddr = addr & HPAGE_PMD_MASK;
> + unsigned long haddr = ALIGN_DOWN(addr, HPAGE_PMD_SIZE);
> struct vm_area_struct *vma = find_vma(mm, haddr);
> struct page *hpage;
> pte_t *start_pte, *pte;
> @@ -1584,7 +1584,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
> if (vma->anon_vma)
> continue;
> addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
> - if (addr & ~HPAGE_PMD_MASK)
> + if (!IS_ALIGNED(addr, HPAGE_PMD_SIZE))
> continue;
> if (vma->vm_end < addr + HPAGE_PMD_SIZE)
> continue;
> @@ -2070,7 +2070,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> {
> struct mm_slot *mm_slot;
> struct mm_struct *mm;
> - struct vm_area_struct *vma;
> + struct vm_area_struct *vma = NULL;
> int progress = 0;
>
> VM_BUG_ON(!pages);
> @@ -2092,7 +2092,6 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> * Don't wait for semaphore (to avoid long wait times). Just move to
> * the next mm on the list.
> */
> - vma = NULL;
> if (unlikely(!mmap_read_trylock(mm)))
> goto breakouterloop_mmap_lock;
> if (likely(!khugepaged_test_exit(mm)))
> @@ -2112,15 +2111,15 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> progress++;
> continue;
> }
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (hstart >= hend)
> goto skip;
> if (khugepaged_scan.address > hend)
> goto skip;
> if (khugepaged_scan.address < hstart)
> khugepaged_scan.address = hstart;
> - VM_BUG_ON(khugepaged_scan.address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(khugepaged_scan.address, HPAGE_PMD_SIZE));
> if (shmem_file(vma->vm_file) && !shmem_huge_enabled(vma))
> goto skip;
>
> --
> 2.27.0
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 1/2] mm: khugepaged: use macro to align addresses
@ 2021-04-07 21:40 ` Yang Shi
0 siblings, 0 replies; 8+ messages in thread
From: Yang Shi @ 2021-04-07 21:40 UTC (permalink / raw)
To: yanfei.xu; +Cc: Linux MM, Linux Kernel Mailing List
On Tue, Apr 6, 2021 at 8:06 PM <yanfei.xu@windriver.com> wrote:
>
> From: Yanfei Xu <yanfei.xu@windriver.com>
>
> We could use macro to deal with the addresses which need to be aligned
> to improve readability of codes.
Reviewed-by: Yang Shi <shy828301@gmail.com>
>
> Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
> ---
> mm/khugepaged.c | 27 +++++++++++++--------------
> 1 file changed, 13 insertions(+), 14 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index a7d6cb912b05..a6012b9259a2 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -517,8 +517,8 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
> if (!hugepage_vma_check(vma, vm_flags))
> return 0;
>
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (hstart < hend)
> return khugepaged_enter(vma, vm_flags);
> return 0;
> @@ -979,8 +979,8 @@ static int hugepage_vma_revalidate(struct mm_struct *mm, unsigned long address,
> if (!vma)
> return SCAN_VMA_NULL;
>
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (address < hstart || address + HPAGE_PMD_SIZE > hend)
> return SCAN_ADDRESS_RANGE;
> if (!hugepage_vma_check(vma, vma->vm_flags))
> @@ -1070,7 +1070,7 @@ static void collapse_huge_page(struct mm_struct *mm,
> struct mmu_notifier_range range;
> gfp_t gfp;
>
> - VM_BUG_ON(address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
>
> /* Only allocate from the target node */
> gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;
> @@ -1235,7 +1235,7 @@ static int khugepaged_scan_pmd(struct mm_struct *mm,
> int node = NUMA_NO_NODE, unmapped = 0;
> bool writable = false;
>
> - VM_BUG_ON(address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(address, HPAGE_PMD_SIZE));
>
> pmd = mm_find_pmd(mm, address);
> if (!pmd) {
> @@ -1414,7 +1414,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
> {
> struct mm_slot *mm_slot;
>
> - VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(addr, HPAGE_PMD_SIZE));
>
> spin_lock(&khugepaged_mm_lock);
> mm_slot = get_mm_slot(mm);
> @@ -1437,7 +1437,7 @@ static int khugepaged_add_pte_mapped_thp(struct mm_struct *mm,
> */
> void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
> {
> - unsigned long haddr = addr & HPAGE_PMD_MASK;
> + unsigned long haddr = ALIGN_DOWN(addr, HPAGE_PMD_SIZE);
> struct vm_area_struct *vma = find_vma(mm, haddr);
> struct page *hpage;
> pte_t *start_pte, *pte;
> @@ -1584,7 +1584,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
> if (vma->anon_vma)
> continue;
> addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
> - if (addr & ~HPAGE_PMD_MASK)
> + if (!IS_ALIGNED(addr, HPAGE_PMD_SIZE))
> continue;
> if (vma->vm_end < addr + HPAGE_PMD_SIZE)
> continue;
> @@ -2070,7 +2070,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> {
> struct mm_slot *mm_slot;
> struct mm_struct *mm;
> - struct vm_area_struct *vma;
> + struct vm_area_struct *vma = NULL;
> int progress = 0;
>
> VM_BUG_ON(!pages);
> @@ -2092,7 +2092,6 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> * Don't wait for semaphore (to avoid long wait times). Just move to
> * the next mm on the list.
> */
> - vma = NULL;
> if (unlikely(!mmap_read_trylock(mm)))
> goto breakouterloop_mmap_lock;
> if (likely(!khugepaged_test_exit(mm)))
> @@ -2112,15 +2111,15 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> progress++;
> continue;
> }
> - hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
> - hend = vma->vm_end & HPAGE_PMD_MASK;
> + hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
> + hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
> if (hstart >= hend)
> goto skip;
> if (khugepaged_scan.address > hend)
> goto skip;
> if (khugepaged_scan.address < hstart)
> khugepaged_scan.address = hstart;
> - VM_BUG_ON(khugepaged_scan.address & ~HPAGE_PMD_MASK);
> + VM_BUG_ON(!IS_ALIGNED(khugepaged_scan.address, HPAGE_PMD_SIZE));
> if (shmem_file(vma->vm_file) && !shmem_huge_enabled(vma))
> goto skip;
>
> --
> 2.27.0
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas
2021-04-07 3:05 ` [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas yanfei.xu
@ 2021-04-07 21:40 ` Yang Shi
0 siblings, 0 replies; 8+ messages in thread
From: Yang Shi @ 2021-04-07 21:40 UTC (permalink / raw)
To: Xu, Yanfei; +Cc: Linux MM, Linux Kernel Mailing List
On Tue, Apr 6, 2021 at 8:06 PM <yanfei.xu@windriver.com> wrote:
>
> From: Yanfei Xu <yanfei.xu@windriver.com>
>
> We could check MMF_DISABLE_THP ahead of iterating over all of vma.
> Otherwise if some mm_struct contain a large number of vma, there will
> be amounts meaningless cpu cycles cost.
Reviewed-by: Yang Shi <shy828301@gmail.com>
>
> Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
> ---
> mm/khugepaged.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index a6012b9259a2..f4ad25a7db55 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2094,6 +2094,8 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> */
> if (unlikely(!mmap_read_trylock(mm)))
> goto breakouterloop_mmap_lock;
> + if (test_bit(MMF_DISABLE_THP, &mm->flags))
> + goto breakouterloop;
> if (likely(!khugepaged_test_exit(mm)))
> vma = find_vma(mm, khugepaged_scan.address);
>
> --
> 2.27.0
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas
@ 2021-04-07 21:40 ` Yang Shi
0 siblings, 0 replies; 8+ messages in thread
From: Yang Shi @ 2021-04-07 21:40 UTC (permalink / raw)
To: Xu, Yanfei; +Cc: Linux MM, Linux Kernel Mailing List
On Tue, Apr 6, 2021 at 8:06 PM <yanfei.xu@windriver.com> wrote:
>
> From: Yanfei Xu <yanfei.xu@windriver.com>
>
> We could check MMF_DISABLE_THP ahead of iterating over all of vma.
> Otherwise if some mm_struct contain a large number of vma, there will
> be amounts meaningless cpu cycles cost.
Reviewed-by: Yang Shi <shy828301@gmail.com>
>
> Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
> ---
> mm/khugepaged.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index a6012b9259a2..f4ad25a7db55 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2094,6 +2094,8 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
> */
> if (unlikely(!mmap_read_trylock(mm)))
> goto breakouterloop_mmap_lock;
> + if (test_bit(MMF_DISABLE_THP, &mm->flags))
> + goto breakouterloop;
> if (likely(!khugepaged_test_exit(mm)))
> vma = find_vma(mm, khugepaged_scan.address);
>
> --
> 2.27.0
>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP
2021-04-07 3:05 [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP yanfei.xu
2021-04-07 3:05 ` [PATCH v2 1/2] mm: khugepaged: use macro to align addresses yanfei.xu
2021-04-07 3:05 ` [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas yanfei.xu
@ 2021-04-14 2:14 ` Xu, Yanfei
2 siblings, 0 replies; 8+ messages in thread
From: Xu, Yanfei @ 2021-04-14 2:14 UTC (permalink / raw)
To: shy828301, Andrew Morton; +Cc: linux-mm, linux-kernel
Gentle ping.
On 4/7/21 11:05 AM, yanfei.xu@windriver.com wrote:
> From: Yanfei Xu <yanfei.xu@windriver.com>
>
> v1-->v2:
> 1.correct the wrong location where the goto jump to.
> 2.keep the cond_resched() dropped in v1 still there.
>
> Thanks for Yang's review.
>
> Yanfei Xu (2):
> mm: khugepaged: use macro to align addresses
> mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas
>
> mm/khugepaged.c | 29 +++++++++++++++--------------
> 1 file changed, 15 insertions(+), 14 deletions(-)
>
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-04-14 2:14 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-04-07 3:05 [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP yanfei.xu
2021-04-07 3:05 ` [PATCH v2 1/2] mm: khugepaged: use macro to align addresses yanfei.xu
2021-04-07 21:40 ` Yang Shi
2021-04-07 21:40 ` Yang Shi
2021-04-07 3:05 ` [PATCH v2 2/2] mm: khugepaged: check MMF_DISABLE_THP ahead of iterating over vmas yanfei.xu
2021-04-07 21:40 ` Yang Shi
2021-04-07 21:40 ` Yang Shi
2021-04-14 2:14 ` [PATCH v2 0/2] mm: khugepaged: cleanup and a minor tuning in THP Xu, Yanfei
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.