mm: make rmap_one boolean function

rmap_one's return value controls whether rmap_work should contine to
scan other ptes or not so it's target for changing to boolean.  Return
true if the scan should be continued.  Otherwise, return false to stop
the scanning.

This patch makes rmap_one's return value to boolean.

Link: http://lkml.kernel.org/r/1489555493-14659-10-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 15 insertions, 15 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index 3b40d47..47e8daf 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -724,7 +724,7 @@ struct page_referenced_arg {
 /*
  * arg: page_referenced_arg will be passed
  */
-static int page_referenced_one(struct page *page, struct vm_area_struct *vma,
+static bool page_referenced_one(struct page *page, struct vm_area_struct *vma,
 			unsigned long address, void *arg)
 {
 	struct page_referenced_arg *pra = arg;
@@ -741,7 +741,7 @@ static int page_referenced_one(struct page *page, struct vm_area_struct *vma,
 		if (vma->vm_flags & VM_LOCKED) {
 			page_vma_mapped_walk_done(&pvmw);
 			pra->vm_flags |= VM_LOCKED;
-			return SWAP_FAIL; /* To break the loop */
+			return false; /* To break the loop */
 		}
 
 		if (pvmw.pte) {
@@ -781,9 +781,9 @@ static int page_referenced_one(struct page *page, struct vm_area_struct *vma,
 	}
 
 	if (!pra->mapcount)
-		return SWAP_SUCCESS; /* To break the loop */
+		return false; /* To break the loop */
 
-	return SWAP_AGAIN;
+	return true;
 }
 
 static bool invalid_page_referenced_vma(struct vm_area_struct *vma, void *arg)
@@ -854,7 +854,7 @@ int page_referenced(struct page *page,
 	return pra.referenced;
 }
 
-static int page_mkclean_one(struct page *page, struct vm_area_struct *vma,
+static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma,
 			    unsigned long address, void *arg)
 {
 	struct page_vma_mapped_walk pvmw = {
@@ -907,7 +907,7 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma,
 		}
 	}
 
-	return SWAP_AGAIN;
+	return true;
 }
 
 static bool invalid_mkclean_vma(struct vm_area_struct *vma, void *arg)
@@ -1290,7 +1290,7 @@ void page_remove_rmap(struct page *page, bool compound)
 /*
  * @arg: enum ttu_flags will be passed to this argument
  */
-static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
+static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		     unsigned long address, void *arg)
 {
 	struct mm_struct *mm = vma->vm_mm;
@@ -1301,12 +1301,12 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 	};
 	pte_t pteval;
 	struct page *subpage;
-	int ret = SWAP_AGAIN;
+	bool ret = true;
 	enum ttu_flags flags = (enum ttu_flags)arg;
 
 	/* munlock has nothing to gain from examining un-locked vmas */
 	if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED))
-		return SWAP_AGAIN;
+		return true;
 
 	if (flags & TTU_SPLIT_HUGE_PMD) {
 		split_huge_pmd_address(vma, address,
@@ -1329,7 +1329,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 					 */
 					mlock_vma_page(page);
 				}
-				ret = SWAP_FAIL;
+				ret = false;
 				page_vma_mapped_walk_done(&pvmw);
 				break;
 			}
@@ -1347,7 +1347,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		if (!(flags & TTU_IGNORE_ACCESS)) {
 			if (ptep_clear_flush_young_notify(vma, address,
 						pvmw.pte)) {
-				ret = SWAP_FAIL;
+				ret = false;
 				page_vma_mapped_walk_done(&pvmw);
 				break;
 			}
@@ -1437,14 +1437,14 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 				 */
 				set_pte_at(mm, address, pvmw.pte, pteval);
 				SetPageSwapBacked(page);
-				ret = SWAP_FAIL;
+				ret = false;
 				page_vma_mapped_walk_done(&pvmw);
 				break;
 			}
 
 			if (swap_duplicate(entry) < 0) {
 				set_pte_at(mm, address, pvmw.pte, pteval);
-				ret = SWAP_FAIL;
+				ret = false;
 				page_vma_mapped_walk_done(&pvmw);
 				break;
 			}
@@ -1636,7 +1636,7 @@ static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
 		if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
 			continue;
 
-		if (SWAP_AGAIN != rwc->rmap_one(page, vma, address, rwc->arg))
+		if (!rwc->rmap_one(page, vma, address, rwc->arg))
 			break;
 		if (rwc->done && rwc->done(page))
 			break;
@@ -1690,7 +1690,7 @@ static void rmap_walk_file(struct page *page, struct rmap_walk_control *rwc,
 		if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
 			continue;
 
-		if (SWAP_AGAIN != rwc->rmap_one(page, vma, address, rwc->arg))
+		if (!rwc->rmap_one(page, vma, address, rwc->arg))
 			goto done;
 		if (rwc->done && rwc->done(page))
 			goto done;