2 * Simple NUMA memory policy for the Linux kernel.
4 * Copyright 2003,2004 Andi Kleen, SuSE Labs.
5 * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc.
6 * Subject to the GNU Public License, version 2.
8 * NUMA policy allows the user to give hints in which node(s) memory should
11 * Support four policies per VMA and per process:
13 * The VMA policy has priority over the process policy for a page fault.
15 * interleave Allocate memory interleaved over a set of nodes,
16 * with normal fallback if it fails.
17 * For VMA based allocations this interleaves based on the
18 * offset into the backing object or offset into the mapping
19 * for anonymous memory. For process policy an process counter
22 * bind Only allocate memory on a specific set of nodes,
24 * FIXME: memory is allocated starting with the first node
25 * to the last. It would be better if bind would truly restrict
26 * the allocation to memory nodes instead
28 * preferred Try a specific node first before normal fallback.
29 * As a special case node -1 here means do the allocation
30 * on the local CPU. This is normally identical to default,
31 * but useful to set in a VMA when you have a non default
34 * default Allocate on the local node first, or when on a VMA
35 * use the process policy. This is what Linux always did
36 * in a NUMA aware kernel and still does by, ahem, default.
38 * The process policy is applied for most non interrupt memory allocations
39 * in that process' context. Interrupts ignore the policies and always
40 * try to allocate on the local CPU. The VMA policy is only applied for memory
41 * allocations for a VMA in the VM.
43 * Currently there are a few corner cases in swapping where the policy
44 * is not applied, but the majority should be handled. When process policy
45 * is used it is not remembered over swap outs/swap ins.
47 * Only the highest zone in the zone hierarchy gets policied. Allocations
48 * requesting a lower zone just use default policy. This implies that
49 * on systems with highmem kernel lowmem allocation don't get policied.
50 * Same with GFP_DMA allocations.
52 * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between
53 * all users and remembered even when nobody has memory mapped.
57 fix mmap readahead to honour policy and enable policy for any page cache
59 statistics for bigpages
60 global policy for page cache? currently it uses process policy. Requires
62 handle mremap for shared memory (currently ignored for the policy)
64 make bind policy root only? It can trigger oom much faster and the
65 kernel is not always grateful with that.
66 could replace all the switch()es with a mempolicy_ops structure.
69 #include <linux/mempolicy.h>
71 #include <linux/highmem.h>
72 #include <linux/hugetlb.h>
73 #include <linux/kernel.h>
74 #include <linux/sched.h>
75 #include <linux/nodemask.h>
76 #include <linux/cpuset.h>
77 #include <linux/gfp.h>
78 #include <linux/slab.h>
79 #include <linux/string.h>
80 #include <linux/module.h>
81 #include <linux/nsproxy.h>
82 #include <linux/interrupt.h>
83 #include <linux/init.h>
84 #include <linux/compat.h>
85 #include <linux/swap.h>
86 #include <linux/seq_file.h>
87 #include <linux/proc_fs.h>
88 #include <linux/migrate.h>
89 #include <linux/rmap.h>
90 #include <linux/security.h>
91 #include <linux/syscalls.h>
93 #include <asm/tlbflush.h>
94 #include <asm/uaccess.h>
97 #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
98 #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
99 #define MPOL_MF_STATS (MPOL_MF_INTERNAL << 2) /* Gather statistics */
101 static struct kmem_cache *policy_cache;
102 static struct kmem_cache *sn_cache;
104 /* Highest zone. An specific allocation for a zone below that is not
106 enum zone_type policy_zone = 0;
108 struct mempolicy default_policy = {
109 .refcnt = ATOMIC_INIT(1), /* never free it */
110 .policy = MPOL_DEFAULT,
113 static void mpol_rebind_policy(struct mempolicy *pol,
114 const nodemask_t *newmask);
116 /* Do sanity checking on a policy */
117 static int mpol_check_policy(unsigned short mode, nodemask_t *nodes)
119 int was_empty, is_empty;
125 * "Contextualize" the in-coming nodemast for cpusets:
126 * Remember whether in-coming nodemask was empty, If not,
127 * restrict the nodes to the allowed nodes in the cpuset.
128 * This is guaranteed to be a subset of nodes with memory.
130 cpuset_update_task_memory_state();
131 is_empty = was_empty = nodes_empty(*nodes);
133 nodes_and(*nodes, *nodes, cpuset_current_mems_allowed);
134 is_empty = nodes_empty(*nodes); /* after "contextualization" */
140 * require caller to specify an empty nodemask
141 * before "contextualization"
147 case MPOL_INTERLEAVE:
149 * require at least 1 valid node after "contextualization"
156 * Did caller specify invalid nodes?
157 * Don't silently accept this as "local allocation".
159 if (!was_empty && is_empty)
168 /* Check that the nodemask contains at least one populated zone */
169 static int is_valid_nodemask(nodemask_t *nodemask)
173 /* Check that there is something useful in this mask */
176 for_each_node_mask(nd, *nodemask) {
179 for (k = 0; k <= policy_zone; k++) {
180 z = &NODE_DATA(nd)->node_zones[k];
181 if (z->present_pages > 0)
189 /* Create a new policy */
190 static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
193 struct mempolicy *policy;
195 pr_debug("setting mode %d flags %d nodes[0] %lx\n",
196 mode, flags, nodes ? nodes_addr(*nodes)[0] : -1);
198 if (mode == MPOL_DEFAULT)
200 policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
202 return ERR_PTR(-ENOMEM);
203 atomic_set(&policy->refcnt, 1);
205 case MPOL_INTERLEAVE:
206 policy->v.nodes = *nodes;
207 if (nodes_weight(policy->v.nodes) == 0) {
208 kmem_cache_free(policy_cache, policy);
209 return ERR_PTR(-EINVAL);
213 policy->v.preferred_node = first_node(*nodes);
214 if (policy->v.preferred_node >= MAX_NUMNODES)
215 policy->v.preferred_node = -1;
218 if (!is_valid_nodemask(nodes)) {
219 kmem_cache_free(policy_cache, policy);
220 return ERR_PTR(-EINVAL);
222 policy->v.nodes = *nodes;
227 policy->policy = mode;
228 policy->flags = flags;
229 policy->cpuset_mems_allowed = cpuset_mems_allowed(current);
233 static void gather_stats(struct page *, void *, int pte_dirty);
234 static void migrate_page_add(struct page *page, struct list_head *pagelist,
235 unsigned long flags);
237 /* Scan through pages checking if pages follow certain conditions. */
238 static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
239 unsigned long addr, unsigned long end,
240 const nodemask_t *nodes, unsigned long flags,
247 orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
252 if (!pte_present(*pte))
254 page = vm_normal_page(vma, addr, *pte);
258 * The check for PageReserved here is important to avoid
259 * handling zero pages and other pages that may have been
260 * marked special by the system.
262 * If the PageReserved would not be checked here then f.e.
263 * the location of the zero page could have an influence
264 * on MPOL_MF_STRICT, zero pages would be counted for
265 * the per node stats, and there would be useless attempts
266 * to put zero pages on the migration list.
268 if (PageReserved(page))
270 nid = page_to_nid(page);
271 if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
274 if (flags & MPOL_MF_STATS)
275 gather_stats(page, private, pte_dirty(*pte));
276 else if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
277 migrate_page_add(page, private, flags);
280 } while (pte++, addr += PAGE_SIZE, addr != end);
281 pte_unmap_unlock(orig_pte, ptl);
285 static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
286 unsigned long addr, unsigned long end,
287 const nodemask_t *nodes, unsigned long flags,
293 pmd = pmd_offset(pud, addr);
295 next = pmd_addr_end(addr, end);
296 if (pmd_none_or_clear_bad(pmd))
298 if (check_pte_range(vma, pmd, addr, next, nodes,
301 } while (pmd++, addr = next, addr != end);
305 static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
306 unsigned long addr, unsigned long end,
307 const nodemask_t *nodes, unsigned long flags,
313 pud = pud_offset(pgd, addr);
315 next = pud_addr_end(addr, end);
316 if (pud_none_or_clear_bad(pud))
318 if (check_pmd_range(vma, pud, addr, next, nodes,
321 } while (pud++, addr = next, addr != end);
325 static inline int check_pgd_range(struct vm_area_struct *vma,
326 unsigned long addr, unsigned long end,
327 const nodemask_t *nodes, unsigned long flags,
333 pgd = pgd_offset(vma->vm_mm, addr);
335 next = pgd_addr_end(addr, end);
336 if (pgd_none_or_clear_bad(pgd))
338 if (check_pud_range(vma, pgd, addr, next, nodes,
341 } while (pgd++, addr = next, addr != end);
346 * Check if all pages in a range are on a set of nodes.
347 * If pagelist != NULL then isolate pages from the LRU and
348 * put them on the pagelist.
350 static struct vm_area_struct *
351 check_range(struct mm_struct *mm, unsigned long start, unsigned long end,
352 const nodemask_t *nodes, unsigned long flags, void *private)
355 struct vm_area_struct *first, *vma, *prev;
357 if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
359 err = migrate_prep();
364 first = find_vma(mm, start);
366 return ERR_PTR(-EFAULT);
368 for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) {
369 if (!(flags & MPOL_MF_DISCONTIG_OK)) {
370 if (!vma->vm_next && vma->vm_end < end)
371 return ERR_PTR(-EFAULT);
372 if (prev && prev->vm_end < vma->vm_start)
373 return ERR_PTR(-EFAULT);
375 if (!is_vm_hugetlb_page(vma) &&
376 ((flags & MPOL_MF_STRICT) ||
377 ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
378 vma_migratable(vma)))) {
379 unsigned long endvma = vma->vm_end;
383 if (vma->vm_start > start)
384 start = vma->vm_start;
385 err = check_pgd_range(vma, start, endvma, nodes,
388 first = ERR_PTR(err);
397 /* Apply policy to a single VMA */
398 static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new)
401 struct mempolicy *old = vma->vm_policy;
403 pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
404 vma->vm_start, vma->vm_end, vma->vm_pgoff,
405 vma->vm_ops, vma->vm_file,
406 vma->vm_ops ? vma->vm_ops->set_policy : NULL);
408 if (vma->vm_ops && vma->vm_ops->set_policy)
409 err = vma->vm_ops->set_policy(vma, new);
412 vma->vm_policy = new;
418 /* Step 2: apply policy to a range and do splits. */
419 static int mbind_range(struct vm_area_struct *vma, unsigned long start,
420 unsigned long end, struct mempolicy *new)
422 struct vm_area_struct *next;
426 for (; vma && vma->vm_start < end; vma = next) {
428 if (vma->vm_start < start)
429 err = split_vma(vma->vm_mm, vma, start, 1);
430 if (!err && vma->vm_end > end)
431 err = split_vma(vma->vm_mm, vma, end, 0);
433 err = policy_vma(vma, new);
441 * Update task->flags PF_MEMPOLICY bit: set iff non-default
442 * mempolicy. Allows more rapid checking of this (combined perhaps
443 * with other PF_* flag bits) on memory allocation hot code paths.
445 * If called from outside this file, the task 'p' should -only- be
446 * a newly forked child not yet visible on the task list, because
447 * manipulating the task flags of a visible task is not safe.
449 * The above limitation is why this routine has the funny name
450 * mpol_fix_fork_child_flag().
452 * It is also safe to call this with a task pointer of current,
453 * which the static wrapper mpol_set_task_struct_flag() does,
454 * for use within this file.
457 void mpol_fix_fork_child_flag(struct task_struct *p)
460 p->flags |= PF_MEMPOLICY;
462 p->flags &= ~PF_MEMPOLICY;
465 static void mpol_set_task_struct_flag(void)
467 mpol_fix_fork_child_flag(current);
470 /* Set the process memory policy */
471 static long do_set_mempolicy(unsigned short mode, unsigned short flags,
474 struct mempolicy *new;
476 if (mpol_check_policy(mode, nodes))
478 new = mpol_new(mode, flags, nodes);
481 mpol_free(current->mempolicy);
482 current->mempolicy = new;
483 mpol_set_task_struct_flag();
484 if (new && new->policy == MPOL_INTERLEAVE)
485 current->il_next = first_node(new->v.nodes);
489 /* Fill a zone bitmap for a policy */
490 static void get_zonemask(struct mempolicy *p, nodemask_t *nodes)
498 case MPOL_INTERLEAVE:
502 /* or use current node instead of memory_map? */
503 if (p->v.preferred_node < 0)
504 *nodes = node_states[N_HIGH_MEMORY];
506 node_set(p->v.preferred_node, *nodes);
513 static int lookup_node(struct mm_struct *mm, unsigned long addr)
518 err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL);
520 err = page_to_nid(p);
526 /* Retrieve NUMA policy */
527 static long do_get_mempolicy(int *policy, nodemask_t *nmask,
528 unsigned long addr, unsigned long flags)
531 struct mm_struct *mm = current->mm;
532 struct vm_area_struct *vma = NULL;
533 struct mempolicy *pol = current->mempolicy;
535 cpuset_update_task_memory_state();
537 ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
540 if (flags & MPOL_F_MEMS_ALLOWED) {
541 if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
543 *policy = 0; /* just so it's initialized */
544 *nmask = cpuset_current_mems_allowed;
548 if (flags & MPOL_F_ADDR) {
549 down_read(&mm->mmap_sem);
550 vma = find_vma_intersection(mm, addr, addr+1);
552 up_read(&mm->mmap_sem);
555 if (vma->vm_ops && vma->vm_ops->get_policy)
556 pol = vma->vm_ops->get_policy(vma, addr);
558 pol = vma->vm_policy;
563 pol = &default_policy;
565 if (flags & MPOL_F_NODE) {
566 if (flags & MPOL_F_ADDR) {
567 err = lookup_node(mm, addr);
571 } else if (pol == current->mempolicy &&
572 pol->policy == MPOL_INTERLEAVE) {
573 *policy = current->il_next;
579 *policy = pol->policy | pol->flags;
582 up_read(¤t->mm->mmap_sem);
588 get_zonemask(pol, nmask);
592 up_read(¤t->mm->mmap_sem);
596 #ifdef CONFIG_MIGRATION
600 static void migrate_page_add(struct page *page, struct list_head *pagelist,
604 * Avoid migrating a page that is shared with others.
606 if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1)
607 isolate_lru_page(page, pagelist);
610 static struct page *new_node_page(struct page *page, unsigned long node, int **x)
612 return alloc_pages_node(node, GFP_HIGHUSER_MOVABLE, 0);
616 * Migrate pages from one node to a target node.
617 * Returns error or the number of pages not migrated.
619 static int migrate_to_node(struct mm_struct *mm, int source, int dest,
627 node_set(source, nmask);
629 check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nmask,
630 flags | MPOL_MF_DISCONTIG_OK, &pagelist);
632 if (!list_empty(&pagelist))
633 err = migrate_pages(&pagelist, new_node_page, dest);
639 * Move pages between the two nodesets so as to preserve the physical
640 * layout as much as possible.
642 * Returns the number of page that could not be moved.
644 int do_migrate_pages(struct mm_struct *mm,
645 const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
652 down_read(&mm->mmap_sem);
654 err = migrate_vmas(mm, from_nodes, to_nodes, flags);
659 * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
660 * bit in 'to' is not also set in 'tmp'. Clear the found 'source'
661 * bit in 'tmp', and return that <source, dest> pair for migration.
662 * The pair of nodemasks 'to' and 'from' define the map.
664 * If no pair of bits is found that way, fallback to picking some
665 * pair of 'source' and 'dest' bits that are not the same. If the
666 * 'source' and 'dest' bits are the same, this represents a node
667 * that will be migrating to itself, so no pages need move.
669 * If no bits are left in 'tmp', or if all remaining bits left
670 * in 'tmp' correspond to the same bit in 'to', return false
671 * (nothing left to migrate).
673 * This lets us pick a pair of nodes to migrate between, such that
674 * if possible the dest node is not already occupied by some other
675 * source node, minimizing the risk of overloading the memory on a
676 * node that would happen if we migrated incoming memory to a node
677 * before migrating outgoing memory source that same node.
679 * A single scan of tmp is sufficient. As we go, we remember the
680 * most recent <s, d> pair that moved (s != d). If we find a pair
681 * that not only moved, but what's better, moved to an empty slot
682 * (d is not set in tmp), then we break out then, with that pair.
683 * Otherwise when we finish scannng from_tmp, we at least have the
684 * most recent <s, d> pair that moved. If we get all the way through
685 * the scan of tmp without finding any node that moved, much less
686 * moved to an empty node, then there is nothing left worth migrating.
690 while (!nodes_empty(tmp)) {
695 for_each_node_mask(s, tmp) {
696 d = node_remap(s, *from_nodes, *to_nodes);
700 source = s; /* Node moved. Memorize */
703 /* dest not in remaining from nodes? */
704 if (!node_isset(dest, tmp))
710 node_clear(source, tmp);
711 err = migrate_to_node(mm, source, dest, flags);
718 up_read(&mm->mmap_sem);
726 * Allocate a new page for page migration based on vma policy.
727 * Start assuming that page is mapped by vma pointed to by @private.
728 * Search forward from there, if not. N.B., this assumes that the
729 * list of pages handed to migrate_pages()--which is how we get here--
730 * is in virtual address order.
732 static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
734 struct vm_area_struct *vma = (struct vm_area_struct *)private;
735 unsigned long uninitialized_var(address);
738 address = page_address_in_vma(page, vma);
739 if (address != -EFAULT)
745 * if !vma, alloc_page_vma() will use task or system default policy
747 return alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
751 static void migrate_page_add(struct page *page, struct list_head *pagelist,
756 int do_migrate_pages(struct mm_struct *mm,
757 const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
762 static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
768 static long do_mbind(unsigned long start, unsigned long len,
769 unsigned short mode, unsigned short mode_flags,
770 nodemask_t *nmask, unsigned long flags)
772 struct vm_area_struct *vma;
773 struct mm_struct *mm = current->mm;
774 struct mempolicy *new;
779 if (flags & ~(unsigned long)(MPOL_MF_STRICT |
780 MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
782 if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
785 if (start & ~PAGE_MASK)
788 if (mode == MPOL_DEFAULT)
789 flags &= ~MPOL_MF_STRICT;
791 len = (len + PAGE_SIZE - 1) & PAGE_MASK;
799 if (mpol_check_policy(mode, nmask))
802 new = mpol_new(mode, mode_flags, nmask);
807 * If we are using the default policy then operation
808 * on discontinuous address spaces is okay after all
811 flags |= MPOL_MF_DISCONTIG_OK;
813 pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n",
814 start, start + len, mode, mode_flags,
815 nmask ? nodes_addr(*nmask)[0] : -1);
817 down_write(&mm->mmap_sem);
818 vma = check_range(mm, start, end, nmask,
819 flags | MPOL_MF_INVERT, &pagelist);
825 err = mbind_range(vma, start, end, new);
827 if (!list_empty(&pagelist))
828 nr_failed = migrate_pages(&pagelist, new_vma_page,
831 if (!err && nr_failed && (flags & MPOL_MF_STRICT))
835 up_write(&mm->mmap_sem);
841 * User space interface with variable sized bitmaps for nodelists.
844 /* Copy a node mask from user space. */
845 static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
846 unsigned long maxnode)
849 unsigned long nlongs;
850 unsigned long endmask;
854 if (maxnode == 0 || !nmask)
856 if (maxnode > PAGE_SIZE*BITS_PER_BYTE)
859 nlongs = BITS_TO_LONGS(maxnode);
860 if ((maxnode % BITS_PER_LONG) == 0)
863 endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
865 /* When the user specified more nodes than supported just check
866 if the non supported part is all zero. */
867 if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
868 if (nlongs > PAGE_SIZE/sizeof(long))
870 for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
872 if (get_user(t, nmask + k))
874 if (k == nlongs - 1) {
880 nlongs = BITS_TO_LONGS(MAX_NUMNODES);
884 if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long)))
886 nodes_addr(*nodes)[nlongs-1] &= endmask;
890 /* Copy a kernel node mask to user space */
891 static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
894 unsigned long copy = ALIGN(maxnode-1, 64) / 8;
895 const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long);
898 if (copy > PAGE_SIZE)
900 if (clear_user((char __user *)mask + nbytes, copy - nbytes))
904 return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
907 asmlinkage long sys_mbind(unsigned long start, unsigned long len,
909 unsigned long __user *nmask, unsigned long maxnode,
914 unsigned short mode_flags;
916 mode_flags = mode & MPOL_MODE_FLAGS;
917 mode &= ~MPOL_MODE_FLAGS;
918 if (mode >= MPOL_MAX)
920 err = get_nodes(&nodes, nmask, maxnode);
923 return do_mbind(start, len, mode, mode_flags, &nodes, flags);
926 /* Set the process memory policy */
927 asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
928 unsigned long maxnode)
932 unsigned short flags;
934 flags = mode & MPOL_MODE_FLAGS;
935 mode &= ~MPOL_MODE_FLAGS;
936 if ((unsigned int)mode >= MPOL_MAX)
938 err = get_nodes(&nodes, nmask, maxnode);
941 return do_set_mempolicy(mode, flags, &nodes);
944 asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
945 const unsigned long __user *old_nodes,
946 const unsigned long __user *new_nodes)
948 struct mm_struct *mm;
949 struct task_struct *task;
952 nodemask_t task_nodes;
955 err = get_nodes(&old, old_nodes, maxnode);
959 err = get_nodes(&new, new_nodes, maxnode);
963 /* Find the mm_struct */
964 read_lock(&tasklist_lock);
965 task = pid ? find_task_by_vpid(pid) : current;
967 read_unlock(&tasklist_lock);
970 mm = get_task_mm(task);
971 read_unlock(&tasklist_lock);
977 * Check if this process has the right to modify the specified
978 * process. The right exists if the process has administrative
979 * capabilities, superuser privileges or the same
980 * userid as the target process.
982 if ((current->euid != task->suid) && (current->euid != task->uid) &&
983 (current->uid != task->suid) && (current->uid != task->uid) &&
984 !capable(CAP_SYS_NICE)) {
989 task_nodes = cpuset_mems_allowed(task);
990 /* Is the user allowed to access the target nodes? */
991 if (!nodes_subset(new, task_nodes) && !capable(CAP_SYS_NICE)) {
996 if (!nodes_subset(new, node_states[N_HIGH_MEMORY])) {
1001 err = security_task_movememory(task);
1005 err = do_migrate_pages(mm, &old, &new,
1006 capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE);
1013 /* Retrieve NUMA policy */
1014 asmlinkage long sys_get_mempolicy(int __user *policy,
1015 unsigned long __user *nmask,
1016 unsigned long maxnode,
1017 unsigned long addr, unsigned long flags)
1020 int uninitialized_var(pval);
1023 if (nmask != NULL && maxnode < MAX_NUMNODES)
1026 err = do_get_mempolicy(&pval, &nodes, addr, flags);
1031 if (policy && put_user(pval, policy))
1035 err = copy_nodes_to_user(nmask, maxnode, &nodes);
1040 #ifdef CONFIG_COMPAT
1042 asmlinkage long compat_sys_get_mempolicy(int __user *policy,
1043 compat_ulong_t __user *nmask,
1044 compat_ulong_t maxnode,
1045 compat_ulong_t addr, compat_ulong_t flags)
1048 unsigned long __user *nm = NULL;
1049 unsigned long nr_bits, alloc_size;
1050 DECLARE_BITMAP(bm, MAX_NUMNODES);
1052 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1053 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1056 nm = compat_alloc_user_space(alloc_size);
1058 err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags);
1060 if (!err && nmask) {
1061 err = copy_from_user(bm, nm, alloc_size);
1062 /* ensure entire bitmap is zeroed */
1063 err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8);
1064 err |= compat_put_bitmap(nmask, bm, nr_bits);
1070 asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
1071 compat_ulong_t maxnode)
1074 unsigned long __user *nm = NULL;
1075 unsigned long nr_bits, alloc_size;
1076 DECLARE_BITMAP(bm, MAX_NUMNODES);
1078 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1079 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1082 err = compat_get_bitmap(bm, nmask, nr_bits);
1083 nm = compat_alloc_user_space(alloc_size);
1084 err |= copy_to_user(nm, bm, alloc_size);
1090 return sys_set_mempolicy(mode, nm, nr_bits+1);
1093 asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
1094 compat_ulong_t mode, compat_ulong_t __user *nmask,
1095 compat_ulong_t maxnode, compat_ulong_t flags)
1098 unsigned long __user *nm = NULL;
1099 unsigned long nr_bits, alloc_size;
1102 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1103 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1106 err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits);
1107 nm = compat_alloc_user_space(alloc_size);
1108 err |= copy_to_user(nm, nodes_addr(bm), alloc_size);
1114 return sys_mbind(start, len, mode, nm, nr_bits+1, flags);
1120 * get_vma_policy(@task, @vma, @addr)
1121 * @task - task for fallback if vma policy == default
1122 * @vma - virtual memory area whose policy is sought
1123 * @addr - address in @vma for shared policy lookup
1125 * Returns effective policy for a VMA at specified address.
1126 * Falls back to @task or system default policy, as necessary.
1127 * Returned policy has extra reference count if shared, vma,
1128 * or some other task's policy [show_numa_maps() can pass
1129 * @task != current]. It is the caller's responsibility to
1130 * free the reference in these cases.
1132 static struct mempolicy * get_vma_policy(struct task_struct *task,
1133 struct vm_area_struct *vma, unsigned long addr)
1135 struct mempolicy *pol = task->mempolicy;
1139 if (vma->vm_ops && vma->vm_ops->get_policy) {
1140 pol = vma->vm_ops->get_policy(vma, addr);
1141 shared_pol = 1; /* if pol non-NULL, add ref below */
1142 } else if (vma->vm_policy &&
1143 vma->vm_policy->policy != MPOL_DEFAULT)
1144 pol = vma->vm_policy;
1147 pol = &default_policy;
1148 else if (!shared_pol && pol != current->mempolicy)
1149 mpol_get(pol); /* vma or other task's policy */
1153 /* Return a nodemask representing a mempolicy */
1154 static nodemask_t *nodemask_policy(gfp_t gfp, struct mempolicy *policy)
1156 /* Lower zones don't get a nodemask applied for MPOL_BIND */
1157 if (unlikely(policy->policy == MPOL_BIND) &&
1158 gfp_zone(gfp) >= policy_zone &&
1159 cpuset_nodemask_valid_mems_allowed(&policy->v.nodes))
1160 return &policy->v.nodes;
1165 /* Return a zonelist representing a mempolicy */
1166 static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy)
1170 switch (policy->policy) {
1171 case MPOL_PREFERRED:
1172 nd = policy->v.preferred_node;
1174 nd = numa_node_id();
1178 * Normally, MPOL_BIND allocations node-local are node-local
1179 * within the allowed nodemask. However, if __GFP_THISNODE is
1180 * set and the current node is part of the mask, we use the
1181 * the zonelist for the first node in the mask instead.
1183 nd = numa_node_id();
1184 if (unlikely(gfp & __GFP_THISNODE) &&
1185 unlikely(!node_isset(nd, policy->v.nodes)))
1186 nd = first_node(policy->v.nodes);
1188 case MPOL_INTERLEAVE: /* should not happen */
1190 nd = numa_node_id();
1196 return node_zonelist(nd, gfp);
1199 /* Do dynamic interleaving for a process */
1200 static unsigned interleave_nodes(struct mempolicy *policy)
1203 struct task_struct *me = current;
1206 next = next_node(nid, policy->v.nodes);
1207 if (next >= MAX_NUMNODES)
1208 next = first_node(policy->v.nodes);
1214 * Depending on the memory policy provide a node from which to allocate the
1217 unsigned slab_node(struct mempolicy *policy)
1219 unsigned short pol = policy ? policy->policy : MPOL_DEFAULT;
1222 case MPOL_INTERLEAVE:
1223 return interleave_nodes(policy);
1227 * Follow bind policy behavior and start allocation at the
1230 struct zonelist *zonelist;
1232 enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
1233 zonelist = &NODE_DATA(numa_node_id())->node_zonelists[0];
1234 (void)first_zones_zonelist(zonelist, highest_zoneidx,
1240 case MPOL_PREFERRED:
1241 if (policy->v.preferred_node >= 0)
1242 return policy->v.preferred_node;
1246 return numa_node_id();
1250 /* Do static interleaving for a VMA with known offset. */
1251 static unsigned offset_il_node(struct mempolicy *pol,
1252 struct vm_area_struct *vma, unsigned long off)
1254 unsigned nnodes = nodes_weight(pol->v.nodes);
1255 unsigned target = (unsigned)off % nnodes;
1261 nid = next_node(nid, pol->v.nodes);
1263 } while (c <= target);
1267 /* Determine a node number for interleave */
1268 static inline unsigned interleave_nid(struct mempolicy *pol,
1269 struct vm_area_struct *vma, unsigned long addr, int shift)
1275 * for small pages, there is no difference between
1276 * shift and PAGE_SHIFT, so the bit-shift is safe.
1277 * for huge pages, since vm_pgoff is in units of small
1278 * pages, we need to shift off the always 0 bits to get
1281 BUG_ON(shift < PAGE_SHIFT);
1282 off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
1283 off += (addr - vma->vm_start) >> shift;
1284 return offset_il_node(pol, vma, off);
1286 return interleave_nodes(pol);
1289 #ifdef CONFIG_HUGETLBFS
1291 * huge_zonelist(@vma, @addr, @gfp_flags, @mpol)
1292 * @vma = virtual memory area whose policy is sought
1293 * @addr = address in @vma for shared policy lookup and interleave policy
1294 * @gfp_flags = for requested zone
1295 * @mpol = pointer to mempolicy pointer for reference counted mempolicy
1296 * @nodemask = pointer to nodemask pointer for MPOL_BIND nodemask
1298 * Returns a zonelist suitable for a huge page allocation.
1299 * If the effective policy is 'BIND, returns pointer to local node's zonelist,
1300 * and a pointer to the mempolicy's @nodemask for filtering the zonelist.
1301 * If it is also a policy for which get_vma_policy() returns an extra
1302 * reference, we must hold that reference until after the allocation.
1303 * In that case, return policy via @mpol so hugetlb allocation can drop
1304 * the reference. For non-'BIND referenced policies, we can/do drop the
1305 * reference here, so the caller doesn't need to know about the special case
1306 * for default and current task policy.
1308 struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
1309 gfp_t gfp_flags, struct mempolicy **mpol,
1310 nodemask_t **nodemask)
1312 struct mempolicy *pol = get_vma_policy(current, vma, addr);
1313 struct zonelist *zl;
1315 *mpol = NULL; /* probably no unref needed */
1316 *nodemask = NULL; /* assume !MPOL_BIND */
1317 if (pol->policy == MPOL_BIND) {
1318 *nodemask = &pol->v.nodes;
1319 } else if (pol->policy == MPOL_INTERLEAVE) {
1322 nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
1323 if (unlikely(pol != &default_policy &&
1324 pol != current->mempolicy))
1325 __mpol_free(pol); /* finished with pol */
1326 return node_zonelist(nid, gfp_flags);
1329 zl = zonelist_policy(GFP_HIGHUSER, pol);
1330 if (unlikely(pol != &default_policy && pol != current->mempolicy)) {
1331 if (pol->policy != MPOL_BIND)
1332 __mpol_free(pol); /* finished with pol */
1334 *mpol = pol; /* unref needed after allocation */
1340 /* Allocate a page in interleaved policy.
1341 Own path because it needs to do special accounting. */
1342 static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
1345 struct zonelist *zl;
1348 zl = node_zonelist(nid, gfp);
1349 page = __alloc_pages(gfp, order, zl);
1350 if (page && page_zone(page) == zonelist_zone(&zl->_zonerefs[0]))
1351 inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
1356 * alloc_page_vma - Allocate a page for a VMA.
1359 * %GFP_USER user allocation.
1360 * %GFP_KERNEL kernel allocations,
1361 * %GFP_HIGHMEM highmem/user allocations,
1362 * %GFP_FS allocation should not call back into a file system.
1363 * %GFP_ATOMIC don't sleep.
1365 * @vma: Pointer to VMA or NULL if not available.
1366 * @addr: Virtual Address of the allocation. Must be inside the VMA.
1368 * This function allocates a page from the kernel page pool and applies
1369 * a NUMA policy associated with the VMA or the current process.
1370 * When VMA is not NULL caller must hold down_read on the mmap_sem of the
1371 * mm_struct of the VMA to prevent it from going away. Should be used for
1372 * all allocations for pages that will be mapped into
1373 * user space. Returns NULL when no page can be allocated.
1375 * Should be called with the mm_sem of the vma hold.
1378 alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
1380 struct mempolicy *pol = get_vma_policy(current, vma, addr);
1381 struct zonelist *zl;
1383 cpuset_update_task_memory_state();
1385 if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
1388 nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
1389 if (unlikely(pol != &default_policy &&
1390 pol != current->mempolicy))
1391 __mpol_free(pol); /* finished with pol */
1392 return alloc_page_interleave(gfp, 0, nid);
1394 zl = zonelist_policy(gfp, pol);
1395 if (pol != &default_policy && pol != current->mempolicy) {
1397 * slow path: ref counted policy -- shared or vma
1399 struct page *page = __alloc_pages_nodemask(gfp, 0,
1400 zl, nodemask_policy(gfp, pol));
1405 * fast path: default or task policy
1407 return __alloc_pages_nodemask(gfp, 0, zl, nodemask_policy(gfp, pol));
1411 * alloc_pages_current - Allocate pages.
1414 * %GFP_USER user allocation,
1415 * %GFP_KERNEL kernel allocation,
1416 * %GFP_HIGHMEM highmem allocation,
1417 * %GFP_FS don't call back into a file system.
1418 * %GFP_ATOMIC don't sleep.
1419 * @order: Power of two of allocation size in pages. 0 is a single page.
1421 * Allocate a page from the kernel page pool. When not in
1422 * interrupt context and apply the current process NUMA policy.
1423 * Returns NULL when no page can be allocated.
1425 * Don't call cpuset_update_task_memory_state() unless
1426 * 1) it's ok to take cpuset_sem (can WAIT), and
1427 * 2) allocating for current task (not interrupt).
1429 struct page *alloc_pages_current(gfp_t gfp, unsigned order)
1431 struct mempolicy *pol = current->mempolicy;
1433 if ((gfp & __GFP_WAIT) && !in_interrupt())
1434 cpuset_update_task_memory_state();
1435 if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
1436 pol = &default_policy;
1437 if (pol->policy == MPOL_INTERLEAVE)
1438 return alloc_page_interleave(gfp, order, interleave_nodes(pol));
1439 return __alloc_pages_nodemask(gfp, order,
1440 zonelist_policy(gfp, pol), nodemask_policy(gfp, pol));
1442 EXPORT_SYMBOL(alloc_pages_current);
1445 * If mpol_copy() sees current->cpuset == cpuset_being_rebound, then it
1446 * rebinds the mempolicy its copying by calling mpol_rebind_policy()
1447 * with the mems_allowed returned by cpuset_mems_allowed(). This
1448 * keeps mempolicies cpuset relative after its cpuset moves. See
1449 * further kernel/cpuset.c update_nodemask().
1452 /* Slow path of a mempolicy copy */
1453 struct mempolicy *__mpol_copy(struct mempolicy *old)
1455 struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
1458 return ERR_PTR(-ENOMEM);
1459 if (current_cpuset_is_being_rebound()) {
1460 nodemask_t mems = cpuset_mems_allowed(current);
1461 mpol_rebind_policy(old, &mems);
1464 atomic_set(&new->refcnt, 1);
1468 /* Slow path of a mempolicy comparison */
1469 int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
1473 if (a->policy != b->policy)
1475 switch (a->policy) {
1480 case MPOL_INTERLEAVE:
1481 return nodes_equal(a->v.nodes, b->v.nodes);
1482 case MPOL_PREFERRED:
1483 return a->v.preferred_node == b->v.preferred_node;
1490 /* Slow path of a mpol destructor. */
1491 void __mpol_free(struct mempolicy *p)
1493 if (!atomic_dec_and_test(&p->refcnt))
1495 p->policy = MPOL_DEFAULT;
1496 kmem_cache_free(policy_cache, p);
1500 * Shared memory backing store policy support.
1502 * Remember policies even when nobody has shared memory mapped.
1503 * The policies are kept in Red-Black tree linked from the inode.
1504 * They are protected by the sp->lock spinlock, which should be held
1505 * for any accesses to the tree.
1508 /* lookup first element intersecting start-end */
1509 /* Caller holds sp->lock */
1510 static struct sp_node *
1511 sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
1513 struct rb_node *n = sp->root.rb_node;
1516 struct sp_node *p = rb_entry(n, struct sp_node, nd);
1518 if (start >= p->end)
1520 else if (end <= p->start)
1528 struct sp_node *w = NULL;
1529 struct rb_node *prev = rb_prev(n);
1532 w = rb_entry(prev, struct sp_node, nd);
1533 if (w->end <= start)
1537 return rb_entry(n, struct sp_node, nd);
1540 /* Insert a new shared policy into the list. */
1541 /* Caller holds sp->lock */
1542 static void sp_insert(struct shared_policy *sp, struct sp_node *new)
1544 struct rb_node **p = &sp->root.rb_node;
1545 struct rb_node *parent = NULL;
1550 nd = rb_entry(parent, struct sp_node, nd);
1551 if (new->start < nd->start)
1553 else if (new->end > nd->end)
1554 p = &(*p)->rb_right;
1558 rb_link_node(&new->nd, parent, p);
1559 rb_insert_color(&new->nd, &sp->root);
1560 pr_debug("inserting %lx-%lx: %d\n", new->start, new->end,
1561 new->policy ? new->policy->policy : 0);
1564 /* Find shared policy intersecting idx */
1566 mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
1568 struct mempolicy *pol = NULL;
1571 if (!sp->root.rb_node)
1573 spin_lock(&sp->lock);
1574 sn = sp_lookup(sp, idx, idx+1);
1576 mpol_get(sn->policy);
1579 spin_unlock(&sp->lock);
1583 static void sp_delete(struct shared_policy *sp, struct sp_node *n)
1585 pr_debug("deleting %lx-l%lx\n", n->start, n->end);
1586 rb_erase(&n->nd, &sp->root);
1587 mpol_free(n->policy);
1588 kmem_cache_free(sn_cache, n);
1591 static struct sp_node *sp_alloc(unsigned long start, unsigned long end,
1592 struct mempolicy *pol)
1594 struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL);
1605 /* Replace a policy range. */
1606 static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
1607 unsigned long end, struct sp_node *new)
1609 struct sp_node *n, *new2 = NULL;
1612 spin_lock(&sp->lock);
1613 n = sp_lookup(sp, start, end);
1614 /* Take care of old policies in the same range. */
1615 while (n && n->start < end) {
1616 struct rb_node *next = rb_next(&n->nd);
1617 if (n->start >= start) {
1623 /* Old policy spanning whole new range. */
1626 spin_unlock(&sp->lock);
1627 new2 = sp_alloc(end, n->end, n->policy);
1633 sp_insert(sp, new2);
1641 n = rb_entry(next, struct sp_node, nd);
1645 spin_unlock(&sp->lock);
1647 mpol_free(new2->policy);
1648 kmem_cache_free(sn_cache, new2);
1653 void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
1654 unsigned short flags, nodemask_t *policy_nodes)
1656 info->root = RB_ROOT;
1657 spin_lock_init(&info->lock);
1659 if (policy != MPOL_DEFAULT) {
1660 struct mempolicy *newpol;
1662 /* Falls back to MPOL_DEFAULT on any error */
1663 newpol = mpol_new(policy, flags, policy_nodes);
1664 if (!IS_ERR(newpol)) {
1665 /* Create pseudo-vma that contains just the policy */
1666 struct vm_area_struct pvma;
1668 memset(&pvma, 0, sizeof(struct vm_area_struct));
1669 /* Policy covers entire file */
1670 pvma.vm_end = TASK_SIZE;
1671 mpol_set_shared_policy(info, &pvma, newpol);
1677 int mpol_set_shared_policy(struct shared_policy *info,
1678 struct vm_area_struct *vma, struct mempolicy *npol)
1681 struct sp_node *new = NULL;
1682 unsigned long sz = vma_pages(vma);
1684 pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n",
1686 sz, npol ? npol->policy : -1,
1687 npol ? npol->flags : -1,
1688 npol ? nodes_addr(npol->v.nodes)[0] : -1);
1691 new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
1695 err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
1697 kmem_cache_free(sn_cache, new);
1701 /* Free a backing policy store on inode delete. */
1702 void mpol_free_shared_policy(struct shared_policy *p)
1705 struct rb_node *next;
1707 if (!p->root.rb_node)
1709 spin_lock(&p->lock);
1710 next = rb_first(&p->root);
1712 n = rb_entry(next, struct sp_node, nd);
1713 next = rb_next(&n->nd);
1714 rb_erase(&n->nd, &p->root);
1715 mpol_free(n->policy);
1716 kmem_cache_free(sn_cache, n);
1718 spin_unlock(&p->lock);
1721 /* assumes fs == KERNEL_DS */
1722 void __init numa_policy_init(void)
1724 nodemask_t interleave_nodes;
1725 unsigned long largest = 0;
1726 int nid, prefer = 0;
1728 policy_cache = kmem_cache_create("numa_policy",
1729 sizeof(struct mempolicy),
1730 0, SLAB_PANIC, NULL);
1732 sn_cache = kmem_cache_create("shared_policy_node",
1733 sizeof(struct sp_node),
1734 0, SLAB_PANIC, NULL);
1737 * Set interleaving policy for system init. Interleaving is only
1738 * enabled across suitably sized nodes (default is >= 16MB), or
1739 * fall back to the largest node if they're all smaller.
1741 nodes_clear(interleave_nodes);
1742 for_each_node_state(nid, N_HIGH_MEMORY) {
1743 unsigned long total_pages = node_present_pages(nid);
1745 /* Preserve the largest node */
1746 if (largest < total_pages) {
1747 largest = total_pages;
1751 /* Interleave this node? */
1752 if ((total_pages << PAGE_SHIFT) >= (16 << 20))
1753 node_set(nid, interleave_nodes);
1756 /* All too small, use the largest */
1757 if (unlikely(nodes_empty(interleave_nodes)))
1758 node_set(prefer, interleave_nodes);
1760 if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes))
1761 printk("numa_policy_init: interleaving failed\n");
1764 /* Reset policy of current process to default */
1765 void numa_default_policy(void)
1767 do_set_mempolicy(MPOL_DEFAULT, 0, NULL);
1770 /* Migrate a policy to a different set of nodes */
1771 static void mpol_rebind_policy(struct mempolicy *pol,
1772 const nodemask_t *newmask)
1774 nodemask_t *mpolmask;
1779 mpolmask = &pol->cpuset_mems_allowed;
1780 if (nodes_equal(*mpolmask, *newmask))
1783 switch (pol->policy) {
1788 case MPOL_INTERLEAVE:
1789 nodes_remap(tmp, pol->v.nodes, *mpolmask, *newmask);
1791 *mpolmask = *newmask;
1792 current->il_next = node_remap(current->il_next,
1793 *mpolmask, *newmask);
1795 case MPOL_PREFERRED:
1796 pol->v.preferred_node = node_remap(pol->v.preferred_node,
1797 *mpolmask, *newmask);
1798 *mpolmask = *newmask;
1807 * Wrapper for mpol_rebind_policy() that just requires task
1808 * pointer, and updates task mempolicy.
1811 void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
1813 mpol_rebind_policy(tsk->mempolicy, new);
1817 * Rebind each vma in mm to new nodemask.
1819 * Call holding a reference to mm. Takes mm->mmap_sem during call.
1822 void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
1824 struct vm_area_struct *vma;
1826 down_write(&mm->mmap_sem);
1827 for (vma = mm->mmap; vma; vma = vma->vm_next)
1828 mpol_rebind_policy(vma->vm_policy, new);
1829 up_write(&mm->mmap_sem);
1833 * Display pages allocated per node and memory policy via /proc.
1836 static const char * const policy_types[] =
1837 { "default", "prefer", "bind", "interleave" };
1840 * Convert a mempolicy into a string.
1841 * Returns the number of characters in buffer (if positive)
1842 * or an error (negative)
1844 static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
1849 unsigned short mode = pol ? pol->policy : MPOL_DEFAULT;
1856 case MPOL_PREFERRED:
1858 node_set(pol->v.preferred_node, nodes);
1863 case MPOL_INTERLEAVE:
1864 nodes = pol->v.nodes;
1872 l = strlen(policy_types[mode]);
1873 if (buffer + maxlen < p + l + 1)
1876 strcpy(p, policy_types[mode]);
1879 if (!nodes_empty(nodes)) {
1880 if (buffer + maxlen < p + 2)
1883 p += nodelist_scnprintf(p, buffer + maxlen - p, nodes);
1889 unsigned long pages;
1891 unsigned long active;
1892 unsigned long writeback;
1893 unsigned long mapcount_max;
1894 unsigned long dirty;
1895 unsigned long swapcache;
1896 unsigned long node[MAX_NUMNODES];
1899 static void gather_stats(struct page *page, void *private, int pte_dirty)
1901 struct numa_maps *md = private;
1902 int count = page_mapcount(page);
1905 if (pte_dirty || PageDirty(page))
1908 if (PageSwapCache(page))
1911 if (PageActive(page))
1914 if (PageWriteback(page))
1920 if (count > md->mapcount_max)
1921 md->mapcount_max = count;
1923 md->node[page_to_nid(page)]++;
1926 #ifdef CONFIG_HUGETLB_PAGE
1927 static void check_huge_range(struct vm_area_struct *vma,
1928 unsigned long start, unsigned long end,
1929 struct numa_maps *md)
1934 for (addr = start; addr < end; addr += HPAGE_SIZE) {
1935 pte_t *ptep = huge_pte_offset(vma->vm_mm, addr & HPAGE_MASK);
1945 page = pte_page(pte);
1949 gather_stats(page, md, pte_dirty(*ptep));
1953 static inline void check_huge_range(struct vm_area_struct *vma,
1954 unsigned long start, unsigned long end,
1955 struct numa_maps *md)
1960 int show_numa_map(struct seq_file *m, void *v)
1962 struct proc_maps_private *priv = m->private;
1963 struct vm_area_struct *vma = v;
1964 struct numa_maps *md;
1965 struct file *file = vma->vm_file;
1966 struct mm_struct *mm = vma->vm_mm;
1967 struct mempolicy *pol;
1974 md = kzalloc(sizeof(struct numa_maps), GFP_KERNEL);
1978 pol = get_vma_policy(priv->task, vma, vma->vm_start);
1979 mpol_to_str(buffer, sizeof(buffer), pol);
1981 * unref shared or other task's mempolicy
1983 if (pol != &default_policy && pol != current->mempolicy)
1986 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1989 seq_printf(m, " file=");
1990 seq_path(m, &file->f_path, "\n\t= ");
1991 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1992 seq_printf(m, " heap");
1993 } else if (vma->vm_start <= mm->start_stack &&
1994 vma->vm_end >= mm->start_stack) {
1995 seq_printf(m, " stack");
1998 if (is_vm_hugetlb_page(vma)) {
1999 check_huge_range(vma, vma->vm_start, vma->vm_end, md);
2000 seq_printf(m, " huge");
2002 check_pgd_range(vma, vma->vm_start, vma->vm_end,
2003 &node_states[N_HIGH_MEMORY], MPOL_MF_STATS, md);
2010 seq_printf(m," anon=%lu",md->anon);
2013 seq_printf(m," dirty=%lu",md->dirty);
2015 if (md->pages != md->anon && md->pages != md->dirty)
2016 seq_printf(m, " mapped=%lu", md->pages);
2018 if (md->mapcount_max > 1)
2019 seq_printf(m, " mapmax=%lu", md->mapcount_max);
2022 seq_printf(m," swapcache=%lu", md->swapcache);
2024 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
2025 seq_printf(m," active=%lu", md->active);
2028 seq_printf(m," writeback=%lu", md->writeback);
2030 for_each_node_state(n, N_HIGH_MEMORY)
2032 seq_printf(m, " N%d=%lu", n, md->node[n]);
2037 if (m->count < m->size)
2038 m->version = (vma != priv->tail_vma) ? vma->vm_start : 0;