X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fmigrate.c;h=a73504ff5ab982007b2e0355e49f0dedcac65899;hb=58ae83db2a40dea15d4277d499a11dadc823c388;hp=06d0877a66efa74a3d599b4ea50f0c5100dd7a1f;hpb=fe537c0ee86b27fbe0690a7869815da80f492dbd;p=linux-2.6

diff --git a/mm/migrate.c b/mm/migrate.c
index 06d0877a66..a73504ff5a 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -19,6 +19,7 @@
 #include <linux/pagemap.h>
 #include <linux/buffer_head.h>
 #include <linux/mm_inline.h>
+#include <linux/nsproxy.h>
 #include <linux/pagevec.h>
 #include <linux/rmap.h>
 #include <linux/topology.h>
@@ -28,6 +29,7 @@
 #include <linux/mempolicy.h>
 #include <linux/vmalloc.h>
 #include <linux/security.h>
+#include <linux/memcontrol.h>
 
 #include "internal.h"
 
@@ -114,11 +116,6 @@ int putback_lru_pages(struct list_head *l)
 	return count;
 }
 
-static inline int is_swap_pte(pte_t pte)
-{
-	return !pte_none(pte) && !pte_present(pte) && !pte_file(pte);
-}
-
 /*
  * Restore a potential migration pte to a working pte entry
  */
@@ -156,6 +153,11 @@ static void remove_migration_pte(struct vm_area_struct *vma,
  		return;
  	}
 
+	if (mem_cgroup_charge(new, mm, GFP_KERNEL)) {
+		pte_unmap(ptep);
+		return;
+	}
+
  	ptl = pte_lockptr(mm, pmd);
  	spin_lock(ptl);
 	pte = *ptep;
@@ -591,9 +593,10 @@ static int move_to_new_page(struct page *newpage, struct page *page)
 	else
 		rc = fallback_migrate_page(mapping, newpage, page);
 
-	if (!rc)
+	if (!rc) {
+		mem_cgroup_page_migration(page, newpage);
 		remove_migration_ptes(page, newpage);
-	else
+	} else
 		newpage->mapping = NULL;
 
 	unlock_page(newpage);
@@ -612,6 +615,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
 	int *result = NULL;
 	struct page *newpage = get_new_page(page, private, &result);
 	int rcu_locked = 0;
+	int charge = 0;
 
 	if (!newpage)
 		return -ENOMEM;
@@ -644,23 +648,46 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
 		rcu_read_lock();
 		rcu_locked = 1;
 	}
+
 	/*
-	 * This is a corner case handling.
-	 * When a new swap-cache is read into, it is linked to LRU
-	 * and treated as swapcache but has no rmap yet.
-	 * Calling try_to_unmap() against a page->mapping==NULL page is
-	 * BUG. So handle it here.
+	 * Corner case handling:
+	 * 1. When a new swap-cache page is read into, it is added to the LRU
+	 * and treated as swapcache but it has no rmap yet.
+	 * Calling try_to_unmap() against a page->mapping==NULL page will
+	 * trigger a BUG.  So handle it here.
+	 * 2. An orphaned page (see truncate_complete_page) might have
+	 * fs-private metadata. The page can be picked up due to memory
+	 * offlining.  Everywhere else except page reclaim, the page is
+	 * invisible to the vm, so the page can not be migrated.  So try to
+	 * free the metadata, so the page can be freed.
 	 */
-	if (!page->mapping)
+	if (!page->mapping) {
+		if (!PageAnon(page) && PagePrivate(page)) {
+			/*
+			 * Go direct to try_to_free_buffers() here because
+			 * a) that's what try_to_release_page() would do anyway
+			 * b) we may be under rcu_read_lock() here, so we can't
+			 *    use GFP_KERNEL which is what try_to_release_page()
+			 *    needs to be effective.
+			 */
+			try_to_free_buffers(page);
+		}
 		goto rcu_unlock;
+	}
+
+	charge = mem_cgroup_prepare_migration(page);
 	/* Establish migration ptes or remove ptes */
 	try_to_unmap(page, 1);
 
 	if (!page_mapped(page))
 		rc = move_to_new_page(newpage, page);
 
-	if (rc)
+	if (rc) {
 		remove_migration_ptes(page, page);
+		if (charge)
+			mem_cgroup_end_migration(page);
+	} else if (charge)
+ 		mem_cgroup_end_migration(newpage);
 rcu_unlock:
 	if (rcu_locked)
 		rcu_read_unlock();
@@ -705,7 +732,7 @@ move_newpage:
  * The function returns after 10 attempts or if no pages
  * are movable anymore because to has become empty
  * or no retryable pages exist anymore. All pages will be
- * retruned to the LRU or freed.
+ * returned to the LRU or freed.
  *
  * Return: Number of pages not migrated or error code.
  */
@@ -924,7 +951,7 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
 
 	/* Find the mm_struct */
 	read_lock(&tasklist_lock);
-	task = pid ? find_task_by_pid(pid) : current;
+	task = pid ? find_task_by_vpid(pid) : current;
 	if (!task) {
 		read_unlock(&tasklist_lock);
 		return -ESRCH;