[PATCH] page migration cleanup: move fallback handling into special function

[deliverable/linux.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index d8ce5ff6145492469a3b81640946fca58d7e8002..10806b7af40c0a111c544e0635dd31fb24b10809 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -56,13 +56,11 @@
 
 #include <asm/tlbflush.h>
 
-//#define RMAP_DEBUG /* can be enabled only for debugging */
-
-kmem_cache_t *anon_vma_cachep;
+struct kmem_cache *anon_vma_cachep;
 
 static inline void validate_anon_vma(struct vm_area_struct *find_vma)
 {
-#ifdef RMAP_DEBUG
+#ifdef CONFIG_DEBUG_VM
        struct anon_vma *anon_vma = find_vma->anon_vma;
        struct vm_area_struct *vma;
        unsigned int mapcount = 0;
@@ -166,7 +164,8 @@ void anon_vma_unlink(struct vm_area_struct *vma)
                anon_vma_free(anon_vma);
 }
 
-static void anon_vma_ctor(void *data, kmem_cache_t *cachep, unsigned long flags)
+static void anon_vma_ctor(void *data, struct kmem_cache *cachep,
+                         unsigned long flags)
 {
        if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
                                                SLAB_CTOR_CONSTRUCTOR) {
@@ -537,9 +536,6 @@ void page_add_new_anon_rmap(struct page *page,
  */
 void page_add_file_rmap(struct page *page)
 {
-       BUG_ON(PageAnon(page));
-       BUG_ON(!pfn_valid(page_to_pfn(page)));
-
        if (atomic_inc_and_test(&page->_mapcount))
                __inc_page_state(nr_mapped);
 }
@@ -553,13 +549,14 @@ void page_add_file_rmap(struct page *page)
 void page_remove_rmap(struct page *page)
 {
        if (atomic_add_negative(-1, &page->_mapcount)) {
-               if (page_mapcount(page) < 0) {
+#ifdef CONFIG_DEBUG_VM
+               if (unlikely(page_mapcount(page) < 0)) {
                        printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page));
                        printk (KERN_EMERG "  page->flags = %lx\n", page->flags);
                        printk (KERN_EMERG "  page->count = %x\n", page_count(page));
                        printk (KERN_EMERG "  page->mapping = %p\n", page->mapping);
                }
-
+#endif
                BUG_ON(page_mapcount(page) < 0);
                /*
                 * It would be tidy to reset the PageAnon mapping here,
@@ -581,7 +578,7 @@ void page_remove_rmap(struct page *page)
  * repeatedly from either try_to_unmap_anon or try_to_unmap_file.
  */
 static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
-                               int ignore_refs)
+                               int migration)
 {
        struct mm_struct *mm = vma->vm_mm;
        unsigned long address;
@@ -605,7 +602,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
         */
        if ((vma->vm_flags & VM_LOCKED) ||
                        (ptep_clear_flush_young(vma, address, pte)
-                               && !ignore_refs)) {
+                               && !migration)) {
                ret = SWAP_FAIL;
                goto out_unmap;
        }
@@ -739,7 +736,7 @@ static void try_to_unmap_cluster(unsigned long cursor,
        pte_unmap_unlock(pte - 1, ptl);
 }
 
-static int try_to_unmap_anon(struct page *page, int ignore_refs)
+static int try_to_unmap_anon(struct page *page, int migration)
 {
        struct anon_vma *anon_vma;
        struct vm_area_struct *vma;
@@ -750,7 +747,7 @@ static int try_to_unmap_anon(struct page *page, int ignore_refs)
                return ret;
 
        list_for_each_entry(vma, &anon_vma->head, anon_vma_node) {
-               ret = try_to_unmap_one(page, vma, ignore_refs);
+               ret = try_to_unmap_one(page, vma, migration);
                if (ret == SWAP_FAIL || !page_mapped(page))
                        break;
        }
@@ -767,7 +764,7 @@ static int try_to_unmap_anon(struct page *page, int ignore_refs)
  *
  * This function is only called from try_to_unmap for object-based pages.
  */
-static int try_to_unmap_file(struct page *page, int ignore_refs)
+static int try_to_unmap_file(struct page *page, int migration)
 {
        struct address_space *mapping = page->mapping;
        pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
@@ -781,7 +778,7 @@ static int try_to_unmap_file(struct page *page, int ignore_refs)
 
        spin_lock(&mapping->i_mmap_lock);
        vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
-               ret = try_to_unmap_one(page, vma, ignore_refs);
+               ret = try_to_unmap_one(page, vma, migration);
                if (ret == SWAP_FAIL || !page_mapped(page))
                        goto out;
        }
@@ -866,16 +863,16 @@ out:
  * SWAP_AGAIN  - we missed a mapping, try again later
  * SWAP_FAIL   - the page is unswappable
  */
-int try_to_unmap(struct page *page, int ignore_refs)
+int try_to_unmap(struct page *page, int migration)
 {
        int ret;
 
        BUG_ON(!PageLocked(page));
 
        if (PageAnon(page))
-               ret = try_to_unmap_anon(page, ignore_refs);
+               ret = try_to_unmap_anon(page, migration);
        else
-               ret = try_to_unmap_file(page, ignore_refs);
+               ret = try_to_unmap_file(page, migration);
 
        if (!page_mapped(page))
                ret = SWAP_SUCCESS;