Re: [PATCH v9 12/24] mm/migrate: Pass vm_fault pointer to migrate_misplaced_page()

[David Rientjes]

On Tue, 13 Mar 2018, Laurent Dufour wrote:

> migrate_misplaced_page() is only called during the page fault handling so
> it's better to pass the pointer to the struct vm_fault instead of the vma.
> 
> This way during the speculative page fault path the saved vma->vm_flags
> could be used.
> 
> Signed-off-by: Laurent Dufour 

Acked-by: David Rientjes 

[PATCH v9 12/24] mm/migrate: Pass vm_fault pointer to migrate_misplaced_page()

[Laurent Dufour]

migrate_misplaced_page() is only called during the page fault handling so
it's better to pass the pointer to the struct vm_fault instead of the vma.

This way during the speculative page fault path the saved vma->vm_flags
could be used.

Signed-off-by: Laurent Dufour 
---
 include/linux/migrate.h | 4 ++--
 mm/memory.c | 2 +-
 mm/migrate.c| 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index f2b4abbca55e..fd4c3ab7bd9c 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -126,14 +126,14 @@ static inline void __ClearPageMovable(struct page *page)
 #ifdef CONFIG_NUMA_BALANCING
 extern bool pmd_trans_migrating(pmd_t pmd);
 extern int migrate_misplaced_page(struct page *page,
- struct vm_area_struct *vma, int node);
+ struct vm_fault *vmf, int node);
 #else
 static inline bool pmd_trans_migrating(pmd_t pmd)
 {
return false;
 }
 static inline int migrate_misplaced_page(struct page *page,
-struct vm_area_struct *vma, int node)
+struct vm_fault *vmf, int node)
 {
return -EAGAIN; /* can't migrate now */
 }
diff --git a/mm/memory.c b/mm/memory.c
index 46fe92b93682..412014d5785b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3880,7 +3880,7 @@ static int do_numa_page(struct vm_fault *vmf)
}
 
/* Migrate to the requested node */
-   migrated = migrate_misplaced_page(page, vma, target_nid);
+   migrated = migrate_misplaced_page(page, vmf, target_nid);
if (migrated) {
page_nid = target_nid;
flags |= TNF_MIGRATED;
diff --git a/mm/migrate.c b/mm/migrate.c
index 5d0dc7b85f90..ad8692ca6a4f 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1900,7 +1900,7 @@ bool pmd_trans_migrating(pmd_t pmd)
  * node. Caller is expected to have an elevated reference count on
  * the page that will be dropped by this function before returning.
  */
-int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
+int migrate_misplaced_page(struct page *page, struct vm_fault *vmf,
   int node)
 {
pg_data_t *pgdat = NODE_DATA(node);
@@ -1913,7 +1913,7 @@ int migrate_misplaced_page(struct page *page, struct 
vm_area_struct *vma,
 * with execute permissions as they are probably shared libraries.
 */
if (page_mapcount(page) != 1 && page_is_file_cache(page) &&
-   (vma->vm_flags & VM_EXEC))
+   (vmf->vma_flags & VM_EXEC))
goto out;
 
/*
-- 
2.7.4