tools headers UAPI: Sync linux/prctl.h with the kernel sources

[linux-2.6-microblaze.git] / mm / ksm.c

diff --git a/mm/ksm.c b/mm/ksm.c
index 9694ee2..6bbe314 100644 (file)
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -215,8 +215,6 @@ struct rmap_item {
 #define SEQNR_MASK     0x0ff   /* low bits of unstable tree seqnr */
 #define UNSTABLE_FLAG  0x100   /* is a node of the unstable tree */
 #define STABLE_FLAG    0x200   /* is listed from the stable tree */
-#define KSM_FLAG_MASK  (SEQNR_MASK|UNSTABLE_FLAG|STABLE_FLAG)
-                               /* to mask all the flags */
 
 /* The stable and unstable tree heads */
 static struct rb_root one_stable_tree[1] = { RB_ROOT };
@@ -461,7 +459,7 @@ static inline bool ksm_test_exit(struct mm_struct *mm)
  * but taking great care only to touch a ksm page, in a VM_MERGEABLE vma,
  * in case the application has unmapped and remapped mm,addr meanwhile.
  * Could a ksm page appear anywhere else?  Actually yes, in a VM_PFNMAP
- * mmap of /dev/mem or /dev/kmem, where we would not want to touch it.
+ * mmap of /dev/mem, where we would not want to touch it.
  *
  * FAULT_FLAG/FOLL_REMOTE are because we do this outside the context
  * of the process that owns 'vma'.  We also do not want to enforce
@@ -778,12 +776,11 @@ static void remove_rmap_item_from_tree(struct rmap_item *rmap_item)
                struct page *page;
 
                stable_node = rmap_item->head;
-               page = get_ksm_page(stable_node, GET_KSM_PAGE_LOCK);
+               page = get_ksm_page(stable_node, GET_KSM_PAGE_NOLOCK);
                if (!page)
                        goto out;
 
                hlist_del(&rmap_item->hlist);
-               unlock_page(page);
                put_page(page);
 
                if (!hlist_empty(&stable_node->hlist))
@@ -794,6 +791,7 @@ static void remove_rmap_item_from_tree(struct rmap_item *rmap_item)
                stable_node->rmap_hlist_len--;
 
                put_anon_vma(rmap_item->anon_vma);
+               rmap_item->head = NULL;
                rmap_item->address &= PAGE_MASK;
 
        } else if (rmap_item->address & UNSTABLE_FLAG) {
@@ -817,8 +815,7 @@ out:
        cond_resched();         /* we're called from many long loops */
 }
 
-static void remove_trailing_rmap_items(struct mm_slot *mm_slot,
-                                      struct rmap_item **rmap_list)
+static void remove_trailing_rmap_items(struct rmap_item **rmap_list)
 {
        while (*rmap_list) {
                struct rmap_item *rmap_item = *rmap_list;
@@ -989,7 +986,7 @@ static int unmerge_and_remove_all_rmap_items(void)
                                goto error;
                }
 
-               remove_trailing_rmap_items(mm_slot, &mm_slot->rmap_list);
+               remove_trailing_rmap_items(&mm_slot->rmap_list);
                mmap_read_unlock(mm);
 
                spin_lock(&ksm_mmlist_lock);
@@ -1068,7 +1065,7 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
                /*
                 * Ok this is tricky, when get_user_pages_fast() run it doesn't
                 * take any lock, therefore the check that we are going to make
-                * with the pagecount against the mapcount is racey and
+                * with the pagecount against the mapcount is racy and
                 * O_DIRECT can happen right after the check.
                 * So we clear the pte and flush the tlb before the check
                 * this assure us that no O_DIRECT can happen after the check
@@ -1438,7 +1435,7 @@ static struct page *stable_node_dup(struct stable_node **_stable_node_dup,
                         */
                        *_stable_node = found;
                        /*
-                        * Just for robustneess as stable_node is
+                        * Just for robustness, as stable_node is
                         * otherwise left as a stable pointer, the
                         * compiler shall optimize it away at build
                         * time.
@@ -1771,7 +1768,6 @@ chain_append:
         * stable_node_dup is the dup to replace.
         */
        if (stable_node_dup == stable_node) {
-               VM_BUG_ON(is_stable_node_chain(stable_node_dup));
                VM_BUG_ON(is_stable_node_dup(stable_node_dup));
                /* chain is missing so create it */
                stable_node = alloc_stable_node_chain(stable_node_dup,
@@ -1785,7 +1781,6 @@ chain_append:
         * of the current nid for this page
         * content.
         */
-       VM_BUG_ON(!is_stable_node_chain(stable_node));
        VM_BUG_ON(!is_stable_node_dup(stable_node_dup));
        VM_BUG_ON(page_node->head != &migrate_nodes);
        list_del(&page_node->list);
@@ -2337,7 +2332,7 @@ next_mm:
         * Nuke all the rmap_items that are above this current rmap:
         * because there were no VM_MERGEABLE vmas with such addresses.
         */
-       remove_trailing_rmap_items(slot, ksm_scan.rmap_list);
+       remove_trailing_rmap_items(ksm_scan.rmap_list);
 
        spin_lock(&ksm_mmlist_lock);
        ksm_scan.mm_slot = list_entry(slot->mm_list.next,
@@ -2634,7 +2629,7 @@ again:
                        vma = vmac->vma;
 
                        /* Ignore the stable/unstable/sqnr flags */
-                       addr = rmap_item->address & ~KSM_FLAG_MASK;
+                       addr = rmap_item->address & PAGE_MASK;
 
                        if (addr < vma->vm_start || addr >= vma->vm_end)
                                continue;