[PATCH v2 08/10] mm: make rmap_walk void function

[Minchan Kim]

There is no user of return value from rmap_walk friend so this
patch makes them void function.

Signed-off-by: Minchan Kim 
---
 include/linux/ksm.h  |  5 ++---
 include/linux/rmap.h |  4 ++--
 mm/ksm.c | 16 ++--
 mm/rmap.c| 32 +---
 4 files changed, 23 insertions(+), 34 deletions(-)

diff --git a/include/linux/ksm.h b/include/linux/ksm.h
index e1cfda4..78b44a0 100644
--- a/include/linux/ksm.h
+++ b/include/linux/ksm.h
@@ -61,7 +61,7 @@ static inline void set_page_stable_node(struct page *page,
 struct page *ksm_might_need_to_copy(struct page *page,
struct vm_area_struct *vma, unsigned long address);
 
-int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
 void ksm_migrate_page(struct page *newpage, struct page *oldpage);
 
 #else  /* !CONFIG_KSM */
@@ -94,10 +94,9 @@ static inline int page_referenced_ksm(struct page *page,
return 0;
 }
 
-static inline int rmap_walk_ksm(struct page *page,
+static inline void rmap_walk_ksm(struct page *page,
struct rmap_walk_control *rwc)
 {
-   return 0;
 }
 
 static inline void ksm_migrate_page(struct page *newpage, struct page *oldpage)
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 6028c38..1d7d457c 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -264,8 +264,8 @@ struct rmap_walk_control {
bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
 };
 
-int rmap_walk(struct page *page, struct rmap_walk_control *rwc);
-int rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc);
 
 #else  /* !CONFIG_MMU */
 
diff --git a/mm/ksm.c b/mm/ksm.c
index 19b4f2d..6edffb9 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1933,11 +1933,10 @@ struct page *ksm_might_need_to_copy(struct page *page,
return new_page;
 }
 
-int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
+void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
 {
struct stable_node *stable_node;
struct rmap_item *rmap_item;
-   int ret = SWAP_AGAIN;
int search_new_forks = 0;
 
VM_BUG_ON_PAGE(!PageKsm(page), page);
@@ -1950,7 +1949,7 @@ int rmap_walk_ksm(struct page *page, struct 
rmap_walk_control *rwc)
 
stable_node = page_stable_node(page);
if (!stable_node)
-   return ret;
+   return;
 again:
hlist_for_each_entry(rmap_item, _node->hlist, hlist) {
struct anon_vma *anon_vma = rmap_item->anon_vma;
@@ -1978,23 +1977,20 @@ int rmap_walk_ksm(struct page *page, struct 
rmap_walk_control *rwc)
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
continue;
 
-   ret = rwc->rmap_one(page, vma,
-   rmap_item->address, rwc->arg);
-   if (ret != SWAP_AGAIN) {
+   if (SWAP_AGAIN != rwc->rmap_one(page, vma,
+   rmap_item->address, rwc->arg)) {
anon_vma_unlock_read(anon_vma);
-   goto out;
+   return;
}
if (rwc->done && rwc->done(page)) {
anon_vma_unlock_read(anon_vma);
-   goto out;
+   return;
}
}
anon_vma_unlock_read(anon_vma);
}
if (!search_new_forks++)
goto again;
-out:
-   return ret;
 }
 
 #ifdef CONFIG_MIGRATION
diff --git a/mm/rmap.c b/mm/rmap.c
index 04d5355..987b0d2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1603,13 +1603,12 @@ static struct anon_vma *rmap_walk_anon_lock(struct page 
*page,
  * vm_flags for that VMA.  That should be OK, because that vma shouldn't be
  * LOCKED.
  */
-static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
+static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
bool locked)
 {
struct anon_vma *anon_vma;
pgoff_t pgoff_start, pgoff_end;
struct anon_vma_chain *avc;
-   int ret = SWAP_AGAIN;
 
if (locked) {
anon_vma = page_anon_vma(page);
@@ -1619,7 +1618,7 @@ static int rmap_walk_anon(struct page *page, struct 
rmap_walk_control *rwc,
anon_vma = rmap_walk_anon_lock(page, rwc);
}
if (!anon_vma)
-   return ret;
+   return;
 
pgoff_start = page_to_pgoff(page);
pgoff_end = pgoff_start + hpage_nr_pages(page) - 1;
@@ -1633,8 +1632,7 @@ static int rmap_walk_anon(struct page 

[PATCH v2 08/10] mm: make rmap_walk void function

[Minchan Kim]

There is no user of return value from rmap_walk friend so this
patch makes them void function.

Signed-off-by: Minchan Kim 
---
 include/linux/ksm.h  |  5 ++---
 include/linux/rmap.h |  4 ++--
 mm/ksm.c | 16 ++--
 mm/rmap.c| 32 +---
 4 files changed, 23 insertions(+), 34 deletions(-)

diff --git a/include/linux/ksm.h b/include/linux/ksm.h
index e1cfda4..78b44a0 100644
--- a/include/linux/ksm.h
+++ b/include/linux/ksm.h
@@ -61,7 +61,7 @@ static inline void set_page_stable_node(struct page *page,
 struct page *ksm_might_need_to_copy(struct page *page,
struct vm_area_struct *vma, unsigned long address);
 
-int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc);
 void ksm_migrate_page(struct page *newpage, struct page *oldpage);
 
 #else  /* !CONFIG_KSM */
@@ -94,10 +94,9 @@ static inline int page_referenced_ksm(struct page *page,
return 0;
 }
 
-static inline int rmap_walk_ksm(struct page *page,
+static inline void rmap_walk_ksm(struct page *page,
struct rmap_walk_control *rwc)
 {
-   return 0;
 }
 
 static inline void ksm_migrate_page(struct page *newpage, struct page *oldpage)
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 6028c38..1d7d457c 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -264,8 +264,8 @@ struct rmap_walk_control {
bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
 };
 
-int rmap_walk(struct page *page, struct rmap_walk_control *rwc);
-int rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk(struct page *page, struct rmap_walk_control *rwc);
+void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc);
 
 #else  /* !CONFIG_MMU */
 
diff --git a/mm/ksm.c b/mm/ksm.c
index 19b4f2d..6edffb9 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1933,11 +1933,10 @@ struct page *ksm_might_need_to_copy(struct page *page,
return new_page;
 }
 
-int rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
+void rmap_walk_ksm(struct page *page, struct rmap_walk_control *rwc)
 {
struct stable_node *stable_node;
struct rmap_item *rmap_item;
-   int ret = SWAP_AGAIN;
int search_new_forks = 0;
 
VM_BUG_ON_PAGE(!PageKsm(page), page);
@@ -1950,7 +1949,7 @@ int rmap_walk_ksm(struct page *page, struct 
rmap_walk_control *rwc)
 
stable_node = page_stable_node(page);
if (!stable_node)
-   return ret;
+   return;
 again:
hlist_for_each_entry(rmap_item, _node->hlist, hlist) {
struct anon_vma *anon_vma = rmap_item->anon_vma;
@@ -1978,23 +1977,20 @@ int rmap_walk_ksm(struct page *page, struct 
rmap_walk_control *rwc)
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
continue;
 
-   ret = rwc->rmap_one(page, vma,
-   rmap_item->address, rwc->arg);
-   if (ret != SWAP_AGAIN) {
+   if (SWAP_AGAIN != rwc->rmap_one(page, vma,
+   rmap_item->address, rwc->arg)) {
anon_vma_unlock_read(anon_vma);
-   goto out;
+   return;
}
if (rwc->done && rwc->done(page)) {
anon_vma_unlock_read(anon_vma);
-   goto out;
+   return;
}
}
anon_vma_unlock_read(anon_vma);
}
if (!search_new_forks++)
goto again;
-out:
-   return ret;
 }
 
 #ifdef CONFIG_MIGRATION
diff --git a/mm/rmap.c b/mm/rmap.c
index 04d5355..987b0d2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1603,13 +1603,12 @@ static struct anon_vma *rmap_walk_anon_lock(struct page 
*page,
  * vm_flags for that VMA.  That should be OK, because that vma shouldn't be
  * LOCKED.
  */
-static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
+static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
bool locked)
 {
struct anon_vma *anon_vma;
pgoff_t pgoff_start, pgoff_end;
struct anon_vma_chain *avc;
-   int ret = SWAP_AGAIN;
 
if (locked) {
anon_vma = page_anon_vma(page);
@@ -1619,7 +1618,7 @@ static int rmap_walk_anon(struct page *page, struct 
rmap_walk_control *rwc,
anon_vma = rmap_walk_anon_lock(page, rwc);
}
if (!anon_vma)
-   return ret;
+   return;
 
pgoff_start = page_to_pgoff(page);
pgoff_end = pgoff_start + hpage_nr_pages(page) - 1;
@@ -1633,8 +1632,7 @@ static int rmap_walk_anon(struct page *page, struct