[PATCH 1/4] mm: drop zap_details::ignore_dirty

[Kirill A. Shutemov]

The only user of ignore_dirty is oom-reaper. But it doesn't really use
it.

ignore_dirty only has effect on file pages mapped with dirty pte.
But oom-repear skips shared VMAs, so there's no way we can dirty file
pte in them.

Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
Acked-by: Michal Hocko <mho...@suse.com>
---
 include/linux/mm.h | 1 -
 mm/memory.c        | 6 ------
 mm/oom_kill.c      | 3 +--
 3 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4424784ac374..7b8e425ac41c 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1148,7 +1148,6 @@ struct zap_details {
        struct address_space *check_mapping;    /* Check page->mapping if set */
        pgoff_t first_index;                    /* Lowest page->index to unmap 
*/
        pgoff_t last_index;                     /* Highest page->index to unmap 
*/
-       bool ignore_dirty;                      /* Ignore dirty pages */
        bool check_swap_entries;                /* Check also swap entries */
 };
 
diff --git a/mm/memory.c b/mm/memory.c
index 455c3e628d52..6ac8fa56080f 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1155,12 +1155,6 @@ static unsigned long zap_pte_range(struct mmu_gather 
*tlb,
 
                        if (!PageAnon(page)) {
                                if (pte_dirty(ptent)) {
-                                       /*
-                                        * oom_reaper cannot tear down dirty
-                                        * pages
-                                        */
-                                       if (unlikely(details && 
details->ignore_dirty))
-                                               continue;
                                        force_flush = 1;
                                        set_page_dirty(page);
                                }
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index ec9f11d4f094..f101db68e760 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -465,8 +465,7 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, 
struct mm_struct *mm)
 {
        struct mmu_gather tlb;
        struct vm_area_struct *vma;
-       struct zap_details details = {.check_swap_entries = true,
-                                     .ignore_dirty = true};
+       struct zap_details details = {.check_swap_entries = true};
        bool ret = true;
 
        /*
-- 
2.10.2