#include <linux/swap.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
-#include <linux/migrate.h>
#include <linux/vs_cvirt.h>
#include <asm/tlbflush.h>
#define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
#define MPOL_MF_STATS (MPOL_MF_INTERNAL << 2) /* Gather statistics */
-static struct kmem_cache *policy_cache;
-static struct kmem_cache *sn_cache;
+/* The number of pages to migrate per call to migrate_pages() */
+#define MIGRATE_CHUNK_SIZE 256
+
+static kmem_cache_t *policy_cache;
+static kmem_cache_t *sn_cache;
#define PDprintk(fmt...)
struct vm_area_struct *first, *vma, *prev;
if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
+ /* Must have swap device for migration */
+ if (nr_swap_pages <= 0)
+ return ERR_PTR(-ENODEV);
- err = migrate_prep();
- if (err)
- return ERR_PTR(err);
+ /*
+ * Clear the LRU lists so pages can be isolated.
+ * Note that pages may be moved off the LRU after we have
+ * drained them. Those pages will fail to migrate like other
+ * pages that may be busy.
+ */
+ lru_add_drain_all();
}
first = find_vma(mm, start);
return mpol_check_policy(mode, nodes);
}
-
-/*
- * Update task->flags PF_MEMPOLICY bit: set iff non-default
- * mempolicy. Allows more rapid checking of this (combined perhaps
- * with other PF_* flag bits) on memory allocation hot code paths.
- *
- * If called from outside this file, the task 'p' should -only- be
- * a newly forked child not yet visible on the task list, because
- * manipulating the task flags of a visible task is not safe.
- *
- * The above limitation is why this routine has the funny name
- * mpol_fix_fork_child_flag().
- *
- * It is also safe to call this with a task pointer of current,
- * which the static wrapper mpol_set_task_struct_flag() does,
- * for use within this file.
- */
-
-void mpol_fix_fork_child_flag(struct task_struct *p)
-{
- if (p->mempolicy)
- p->flags |= PF_MEMPOLICY;
- else
- p->flags &= ~PF_MEMPOLICY;
-}
-
-static void mpol_set_task_struct_flag(void)
-{
- mpol_fix_fork_child_flag(current);
-}
-
/* Set the process memory policy */
long do_set_mempolicy(int mode, nodemask_t *nodes)
{
return PTR_ERR(new);
mpol_free(current->mempolicy);
current->mempolicy = new;
- mpol_set_task_struct_flag();
if (new && new->policy == MPOL_INTERLEAVE)
current->il_next = first_node(new->v.nodes);
return 0;
return err;
}
-#ifdef CONFIG_MIGRATION
/*
* page migration
*/
+
static void migrate_page_add(struct page *page, struct list_head *pagelist,
unsigned long flags)
{
/*
* Avoid migrating a page that is shared with others.
*/
- if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1)
- isolate_lru_page(page, pagelist);
+ if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) {
+ if (isolate_lru_page(page))
+ list_add_tail(&page->lru, pagelist);
+ }
+}
+
+/*
+ * Migrate the list 'pagelist' of pages to a certain destination.
+ *
+ * Specify destination with either non-NULL vma or dest_node >= 0
+ * Return the number of pages not migrated or error code
+ */
+static int migrate_pages_to(struct list_head *pagelist,
+ struct vm_area_struct *vma, int dest)
+{
+ LIST_HEAD(newlist);
+ LIST_HEAD(moved);
+ LIST_HEAD(failed);
+ int err = 0;
+ unsigned long offset = 0;
+ int nr_pages;
+ struct page *page;
+ struct list_head *p;
+
+redo:
+ nr_pages = 0;
+ list_for_each(p, pagelist) {
+ if (vma) {
+ /*
+ * The address passed to alloc_page_vma is used to
+ * generate the proper interleave behavior. We fake
+ * the address here by an increasing offset in order
+ * to get the proper distribution of pages.
+ *
+ * No decision has been made as to which page
+ * a certain old page is moved to so we cannot
+ * specify the correct address.
+ */
+ page = alloc_page_vma(GFP_HIGHUSER, vma,
+ offset + vma->vm_start);
+ offset += PAGE_SIZE;
+ }
+ else
+ page = alloc_pages_node(dest, GFP_HIGHUSER, 0);
+
+ if (!page) {
+ err = -ENOMEM;
+ goto out;
+ }
+ list_add_tail(&page->lru, &newlist);
+ nr_pages++;
+ if (nr_pages > MIGRATE_CHUNK_SIZE)
+ break;
+ }
+ err = migrate_pages(pagelist, &newlist, &moved, &failed);
+
+ putback_lru_pages(&moved); /* Call release pages instead ?? */
+
+ if (err >= 0 && list_empty(&newlist) && !list_empty(pagelist))
+ goto redo;
+out:
+ /* Return leftover allocated pages */
+ while (!list_empty(&newlist)) {
+ page = list_entry(newlist.next, struct page, lru);
+ list_del(&page->lru);
+ __free_page(page);
+ }
+ list_splice(&failed, pagelist);
+ if (err < 0)
+ return err;
+
+ /* Calculate number of leftover pages */
+ nr_pages = 0;
+ list_for_each(p, pagelist)
+ nr_pages++;
+ return nr_pages;
}
/*
if (err < 0)
return err;
return busy;
-
}
-#else
-
-static void migrate_page_add(struct page *page, struct list_head *pagelist,
- unsigned long flags)
-{
-}
-
-int do_migrate_pages(struct mm_struct *mm,
- const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
-{
- return -ENOSYS;
-}
-#endif
-
long do_mbind(unsigned long start, unsigned long len,
unsigned long mode, nodemask_t *nmask, unsigned long flags)
{
if (!err && nr_failed && (flags & MPOL_MF_STRICT))
err = -EIO;
}
-
if (!list_empty(&pagelist))
putback_lru_pages(&pagelist);
/*
* Check if this process has the right to modify the specified
* process. The right exists if the process has administrative
- * capabilities, superuser privileges or the same
+ * capabilities, superuser priviledges or the same
* userid as the target process.
*/
if ((current->euid != task->suid) && (current->euid != task->uid) &&
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