* Simple NUMA memory policy for the Linux kernel.
*
* Copyright 2003,2004 Andi Kleen, SuSE Labs.
+ * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc.
* Subject to the GNU Public License, version 2.
*
* NUMA policy allows the user to give hints in which node(s) memory should
* offset into the backing object or offset into the mapping
* for anonymous memory. For process policy an process counter
* is used.
+ *
* bind Only allocate memory on a specific set of nodes,
* no fallback.
+ * FIXME: memory is allocated starting with the first node
+ * to the last. It would be better if bind would truly restrict
+ * the allocation to memory nodes instead
+ *
* preferred Try a specific node first before normal fallback.
* As a special case node -1 here means do the allocation
* on the local CPU. This is normally identical to default,
* but useful to set in a VMA when you have a non default
* process policy.
+ *
* default Allocate on the local node first, or when on a VMA
* use the process policy. This is what Linux always did
* in a NUMA aware kernel and still does by, ahem, default.
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
+#include <linux/nodemask.h>
+#include <linux/cpuset.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/compat.h>
#include <linux/mempolicy.h>
+#include <linux/swap.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
+#include <linux/migrate.h>
+#include <linux/rmap.h>
+#include <linux/security.h>
+
+#include <asm/tlbflush.h>
#include <asm/uaccess.h>
-static kmem_cache_t *policy_cache;
-static kmem_cache_t *sn_cache;
+/* Internal flags */
+#define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
+#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;
#define PDprintk(fmt...)
/* Highest zone. An specific allocation for a zone below that is not
policied. */
-static int policy_zone;
+int policy_zone = ZONE_DMA;
-static struct mempolicy default_policy = {
+struct mempolicy default_policy = {
.refcnt = ATOMIC_INIT(1), /* never free it */
.policy = MPOL_DEFAULT,
};
-/* Check if all specified nodes are online */
-static int nodes_online(unsigned long *nodes)
-{
- DECLARE_BITMAP(online2, MAX_NUMNODES);
-
- bitmap_copy(online2, node_online_map, MAX_NUMNODES);
- if (bitmap_empty(online2, MAX_NUMNODES))
- set_bit(0, online2);
- if (!bitmap_subset(nodes, online2, MAX_NUMNODES))
- return -EINVAL;
- return 0;
-}
-
/* Do sanity checking on a policy */
-static int mpol_check_policy(int mode, unsigned long *nodes)
+static int mpol_check_policy(int mode, nodemask_t *nodes)
{
- int empty = bitmap_empty(nodes, MAX_NUMNODES);
+ int empty = nodes_empty(*nodes);
switch (mode) {
case MPOL_DEFAULT:
return -EINVAL;
break;
}
- return nodes_online(nodes);
-}
-
-/* Copy a node mask from user space. */
-static int get_nodes(unsigned long *nodes, unsigned long __user *nmask,
- unsigned long maxnode, int mode)
-{
- unsigned long k;
- unsigned long nlongs;
- unsigned long endmask;
-
- --maxnode;
- bitmap_zero(nodes, MAX_NUMNODES);
- if (maxnode == 0 || !nmask)
- return 0;
-
- nlongs = BITS_TO_LONGS(maxnode);
- if ((maxnode % BITS_PER_LONG) == 0)
- endmask = ~0UL;
- else
- endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
-
- /* When the user specified more nodes than supported just check
- if the non supported part is all zero. */
- if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
- for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
- unsigned long t;
- if (get_user(t, nmask + k))
- return -EFAULT;
- if (k == nlongs - 1) {
- if (t & endmask)
- return -EINVAL;
- } else if (t)
- return -EINVAL;
- }
- nlongs = BITS_TO_LONGS(MAX_NUMNODES);
- endmask = ~0UL;
- }
-
- if (copy_from_user(nodes, nmask, nlongs*sizeof(unsigned long)))
- return -EFAULT;
- nodes[nlongs-1] &= endmask;
- return mpol_check_policy(mode, nodes);
+ return nodes_subset(*nodes, node_online_map) ? 0 : -EINVAL;
}
/* Generate a custom zonelist for the BIND policy. */
-static struct zonelist *bind_zonelist(unsigned long *nodes)
+static struct zonelist *bind_zonelist(nodemask_t *nodes)
{
struct zonelist *zl;
- int num, max, nd;
+ int num, max, nd, k;
- max = 1 + MAX_NR_ZONES * bitmap_weight(nodes, MAX_NUMNODES);
- zl = kmalloc(sizeof(void *) * max, GFP_KERNEL);
+ max = 1 + MAX_NR_ZONES * nodes_weight(*nodes);
+ zl = kmalloc(sizeof(struct zone *) * max, GFP_KERNEL);
if (!zl)
return NULL;
num = 0;
- for (nd = find_first_bit(nodes, MAX_NUMNODES);
- nd < MAX_NUMNODES;
- nd = find_next_bit(nodes, MAX_NUMNODES, 1+nd)) {
- int k;
- for (k = MAX_NR_ZONES-1; k >= 0; k--) {
+ /* First put in the highest zones from all nodes, then all the next
+ lower zones etc. Avoid empty zones because the memory allocator
+ doesn't like them. If you implement node hot removal you
+ have to fix that. */
+ for (k = policy_zone; k >= 0; k--) {
+ for_each_node_mask(nd, *nodes) {
struct zone *z = &NODE_DATA(nd)->node_zones[k];
- if (!z->present_pages)
- continue;
- zl->zones[num++] = z;
- if (k > policy_zone)
- policy_zone = k;
+ if (z->present_pages > 0)
+ zl->zones[num++] = z;
}
}
- BUG_ON(num >= max);
zl->zones[num] = NULL;
return zl;
}
/* Create a new policy */
-static struct mempolicy *mpol_new(int mode, unsigned long *nodes)
+static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
{
struct mempolicy *policy;
- PDprintk("setting mode %d nodes[0] %lx\n", mode, nodes[0]);
+ PDprintk("setting mode %d nodes[0] %lx\n", mode, nodes_addr(*nodes)[0]);
if (mode == MPOL_DEFAULT)
return NULL;
policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
atomic_set(&policy->refcnt, 1);
switch (mode) {
case MPOL_INTERLEAVE:
- bitmap_copy(policy->v.nodes, nodes, MAX_NUMNODES);
+ policy->v.nodes = *nodes;
+ if (nodes_weight(*nodes) == 0) {
+ kmem_cache_free(policy_cache, policy);
+ return ERR_PTR(-EINVAL);
+ }
break;
case MPOL_PREFERRED:
- policy->v.preferred_node = find_first_bit(nodes, MAX_NUMNODES);
+ policy->v.preferred_node = first_node(*nodes);
if (policy->v.preferred_node >= MAX_NUMNODES)
policy->v.preferred_node = -1;
break;
break;
}
policy->policy = mode;
+ policy->cpuset_mems_allowed = cpuset_mems_allowed(current);
return policy;
}
-/* Ensure all existing pages follow the policy. */
-static int
-verify_pages(unsigned long addr, unsigned long end, unsigned long *nodes)
+static void gather_stats(struct page *, void *, int pte_dirty);
+static void migrate_page_add(struct page *page, struct list_head *pagelist,
+ unsigned long flags);
+
+/* Scan through pages checking if pages follow certain conditions. */
+static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
+ unsigned long addr, unsigned long end,
+ const nodemask_t *nodes, unsigned long flags,
+ void *private)
{
- while (addr < end) {
- struct page *p;
- pte_t *pte;
- pmd_t *pmd;
- pgd_t *pgd = pgd_offset_k(addr);
- if (pgd_none(*pgd)) {
- addr = (addr + PGDIR_SIZE) & PGDIR_MASK;
+ pte_t *orig_pte;
+ pte_t *pte;
+ spinlock_t *ptl;
+
+ orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ do {
+ struct page *page;
+ unsigned int nid;
+
+ if (!pte_present(*pte))
continue;
- }
- pmd = pmd_offset(pgd, addr);
- if (pmd_none(*pmd)) {
- addr = (addr + PMD_SIZE) & PMD_MASK;
+ page = vm_normal_page(vma, addr, *pte);
+ if (!page)
continue;
- }
- p = NULL;
- pte = pte_offset_map(pmd, addr);
- if (pte_present(*pte))
- p = pte_page(*pte);
- pte_unmap(pte);
- if (p) {
- unsigned nid = page_to_nid(p);
- if (!test_bit(nid, nodes))
- return -EIO;
- }
- addr += PAGE_SIZE;
- }
+ /*
+ * The check for PageReserved here is important to avoid
+ * handling zero pages and other pages that may have been
+ * marked special by the system.
+ *
+ * If the PageReserved would not be checked here then f.e.
+ * the location of the zero page could have an influence
+ * on MPOL_MF_STRICT, zero pages would be counted for
+ * the per node stats, and there would be useless attempts
+ * to put zero pages on the migration list.
+ */
+ if (PageReserved(page))
+ continue;
+ nid = page_to_nid(page);
+ if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
+ continue;
+
+ if (flags & MPOL_MF_STATS)
+ gather_stats(page, private, pte_dirty(*pte));
+ else if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
+ migrate_page_add(page, private, flags);
+ else
+ break;
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap_unlock(orig_pte, ptl);
+ return addr != end;
+}
+
+static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+ unsigned long addr, unsigned long end,
+ const nodemask_t *nodes, unsigned long flags,
+ void *private)
+{
+ pmd_t *pmd;
+ unsigned long next;
+
+ pmd = pmd_offset(pud, addr);
+ do {
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(pmd))
+ continue;
+ if (check_pte_range(vma, pmd, addr, next, nodes,
+ flags, private))
+ return -EIO;
+ } while (pmd++, addr = next, addr != end);
return 0;
}
-/* Step 1: check the range */
+static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ const nodemask_t *nodes, unsigned long flags,
+ void *private)
+{
+ pud_t *pud;
+ unsigned long next;
+
+ pud = pud_offset(pgd, addr);
+ do {
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(pud))
+ continue;
+ if (check_pmd_range(vma, pud, addr, next, nodes,
+ flags, private))
+ return -EIO;
+ } while (pud++, addr = next, addr != end);
+ return 0;
+}
+
+static inline int check_pgd_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end,
+ const nodemask_t *nodes, unsigned long flags,
+ void *private)
+{
+ pgd_t *pgd;
+ unsigned long next;
+
+ pgd = pgd_offset(vma->vm_mm, addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(pgd))
+ continue;
+ if (check_pud_range(vma, pgd, addr, next, nodes,
+ flags, private))
+ return -EIO;
+ } while (pgd++, addr = next, addr != end);
+ return 0;
+}
+
+/* Check if a vma is migratable */
+static inline int vma_migratable(struct vm_area_struct *vma)
+{
+ if (vma->vm_flags & (
+ VM_LOCKED|VM_IO|VM_HUGETLB|VM_PFNMAP|VM_RESERVED))
+ return 0;
+ return 1;
+}
+
+/*
+ * Check if all pages in a range are on a set of nodes.
+ * If pagelist != NULL then isolate pages from the LRU and
+ * put them on the pagelist.
+ */
static struct vm_area_struct *
check_range(struct mm_struct *mm, unsigned long start, unsigned long end,
- unsigned long *nodes, unsigned long flags)
+ const nodemask_t *nodes, unsigned long flags, void *private)
{
int err;
struct vm_area_struct *first, *vma, *prev;
+ if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
+
+ err = migrate_prep();
+ if (err)
+ return ERR_PTR(err);
+ }
+
first = find_vma(mm, start);
if (!first)
return ERR_PTR(-EFAULT);
prev = NULL;
for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) {
- if (!vma->vm_next && vma->vm_end < end)
- return ERR_PTR(-EFAULT);
- if (prev && prev->vm_end < vma->vm_start)
- return ERR_PTR(-EFAULT);
- if ((flags & MPOL_MF_STRICT) && !is_vm_hugetlb_page(vma)) {
- err = verify_pages(vma->vm_start, vma->vm_end, nodes);
+ if (!(flags & MPOL_MF_DISCONTIG_OK)) {
+ if (!vma->vm_next && vma->vm_end < end)
+ return ERR_PTR(-EFAULT);
+ if (prev && prev->vm_end < vma->vm_start)
+ return ERR_PTR(-EFAULT);
+ }
+ if (!is_vm_hugetlb_page(vma) &&
+ ((flags & MPOL_MF_STRICT) ||
+ ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
+ vma_migratable(vma)))) {
+ unsigned long endvma = vma->vm_end;
+
+ if (endvma > end)
+ endvma = end;
+ if (vma->vm_start > start)
+ start = vma->vm_start;
+ err = check_pgd_range(vma, start, endvma, nodes,
+ flags, private);
if (err) {
first = ERR_PTR(err);
break;
return err;
}
-/* Change policy for a memory range */
-asmlinkage long sys_mbind(unsigned long start, unsigned long len,
- unsigned long mode,
- unsigned long __user *nmask, unsigned long maxnode,
- unsigned flags)
+static int contextualize_policy(int mode, nodemask_t *nodes)
{
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
- struct mempolicy *new;
- unsigned long end;
- DECLARE_BITMAP(nodes, MAX_NUMNODES);
- int err;
+ if (!nodes)
+ return 0;
- if ((flags & ~(unsigned long)(MPOL_MF_STRICT)) || mode > MPOL_MAX)
- return -EINVAL;
- if (start & ~PAGE_MASK)
+ cpuset_update_task_memory_state();
+ if (!cpuset_nodes_subset_current_mems_allowed(*nodes))
return -EINVAL;
- if (mode == MPOL_DEFAULT)
- flags &= ~MPOL_MF_STRICT;
- len = (len + PAGE_SIZE - 1) & PAGE_MASK;
- end = start + len;
- if (end < start)
- return -EINVAL;
- if (end == start)
- return 0;
+ return mpol_check_policy(mode, nodes);
+}
- err = get_nodes(nodes, nmask, maxnode, mode);
- if (err)
- return err;
- new = mpol_new(mode, nodes);
- if (IS_ERR(new))
- return PTR_ERR(new);
+/*
+ * 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.
+ */
- PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len,
- mode,nodes[0]);
+void mpol_fix_fork_child_flag(struct task_struct *p)
+{
+ if (p->mempolicy)
+ p->flags |= PF_MEMPOLICY;
+ else
+ p->flags &= ~PF_MEMPOLICY;
+}
- down_write(&mm->mmap_sem);
- vma = check_range(mm, start, end, nodes, flags);
- err = PTR_ERR(vma);
- if (!IS_ERR(vma))
- err = mbind_range(vma, start, end, new);
- up_write(&mm->mmap_sem);
- mpol_free(new);
- return err;
+static void mpol_set_task_struct_flag(void)
+{
+ mpol_fix_fork_child_flag(current);
}
/* Set the process memory policy */
-asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
- unsigned long maxnode)
+long do_set_mempolicy(int mode, nodemask_t *nodes)
{
- int err;
struct mempolicy *new;
- DECLARE_BITMAP(nodes, MAX_NUMNODES);
- if (mode > MPOL_MAX)
+ if (contextualize_policy(mode, nodes))
return -EINVAL;
- err = get_nodes(nodes, nmask, maxnode, mode);
- if (err)
- return err;
new = mpol_new(mode, nodes);
if (IS_ERR(new))
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 = find_first_bit(new->v.nodes, MAX_NUMNODES);
+ current->il_next = first_node(new->v.nodes);
return 0;
}
/* Fill a zone bitmap for a policy */
-static void get_zonemask(struct mempolicy *p, unsigned long *nodes)
+static void get_zonemask(struct mempolicy *p, nodemask_t *nodes)
{
int i;
- bitmap_zero(nodes, MAX_NUMNODES);
+ nodes_clear(*nodes);
switch (p->policy) {
case MPOL_BIND:
for (i = 0; p->v.zonelist->zones[i]; i++)
- __set_bit(p->v.zonelist->zones[i]->zone_pgdat->node_id, nodes);
+ node_set(p->v.zonelist->zones[i]->zone_pgdat->node_id,
+ *nodes);
break;
case MPOL_DEFAULT:
break;
case MPOL_INTERLEAVE:
- bitmap_copy(nodes, p->v.nodes, MAX_NUMNODES);
+ *nodes = p->v.nodes;
break;
case MPOL_PREFERRED:
/* or use current node instead of online map? */
if (p->v.preferred_node < 0)
- bitmap_copy(nodes, node_online_map, MAX_NUMNODES);
+ *nodes = node_online_map;
else
- __set_bit(p->v.preferred_node, nodes);
+ node_set(p->v.preferred_node, *nodes);
break;
default:
BUG();
err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL);
if (err >= 0) {
- err = page_zone(p)->zone_pgdat->node_id;
+ err = page_to_nid(p);
put_page(p);
}
return err;
}
-/* Copy a kernel node mask to user space */
-static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
- void *nodes, unsigned nbytes)
-{
- unsigned long copy = ALIGN(maxnode-1, 64) / 8;
-
- if (copy > nbytes) {
- if (copy > PAGE_SIZE)
- return -EINVAL;
- if (clear_user((char __user *)mask + nbytes, copy - nbytes))
- return -EFAULT;
- copy = nbytes;
- }
- return copy_to_user(mask, nodes, copy) ? -EFAULT : 0;
-}
-
/* Retrieve NUMA policy */
-asmlinkage long sys_get_mempolicy(int __user *policy,
- unsigned long __user *nmask,
- unsigned long maxnode,
- unsigned long addr, unsigned long flags)
+long do_get_mempolicy(int *policy, nodemask_t *nmask,
+ unsigned long addr, unsigned long flags)
{
- int err, pval;
+ int err;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma = NULL;
struct mempolicy *pol = current->mempolicy;
+ cpuset_update_task_memory_state();
if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR))
return -EINVAL;
- if (nmask != NULL && maxnode < numnodes)
- return -EINVAL;
if (flags & MPOL_F_ADDR) {
down_read(&mm->mmap_sem);
vma = find_vma_intersection(mm, addr, addr+1);
err = lookup_node(mm, addr);
if (err < 0)
goto out;
- pval = err;
+ *policy = err;
} else if (pol == current->mempolicy &&
pol->policy == MPOL_INTERLEAVE) {
- pval = current->il_next;
+ *policy = current->il_next;
} else {
err = -EINVAL;
goto out;
}
} else
- pval = pol->policy;
+ *policy = pol->policy;
- err = -EFAULT;
- if (policy && put_user(pval, policy))
- goto out;
+ if (vma) {
+ up_read(¤t->mm->mmap_sem);
+ vma = NULL;
+ }
err = 0;
- if (nmask) {
- DECLARE_BITMAP(nodes, MAX_NUMNODES);
- get_zonemask(pol, nodes);
- err = copy_nodes_to_user(nmask, maxnode, nodes, sizeof(nodes));
+ if (nmask)
+ get_zonemask(pol, nmask);
+
+ out:
+ if (vma)
+ up_read(¤t->mm->mmap_sem);
+ 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);
+}
+
+static struct page *new_node_page(struct page *page, unsigned long node, int **x)
+{
+ return alloc_pages_node(node, GFP_HIGHUSER, 0);
+}
+
+/*
+ * Migrate pages from one node to a target node.
+ * Returns error or the number of pages not migrated.
+ */
+int migrate_to_node(struct mm_struct *mm, int source, int dest, int flags)
+{
+ nodemask_t nmask;
+ LIST_HEAD(pagelist);
+ int err = 0;
+
+ nodes_clear(nmask);
+ node_set(source, nmask);
+
+ check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nmask,
+ flags | MPOL_MF_DISCONTIG_OK, &pagelist);
+
+ if (!list_empty(&pagelist))
+ err = migrate_pages(&pagelist, new_node_page, dest);
+
+ return err;
+}
+
+/*
+ * Move pages between the two nodesets so as to preserve the physical
+ * layout as much as possible.
+ *
+ * Returns the number of page that could not be moved.
+ */
+int do_migrate_pages(struct mm_struct *mm,
+ const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
+{
+ LIST_HEAD(pagelist);
+ int busy = 0;
+ int err = 0;
+ nodemask_t tmp;
+
+ down_read(&mm->mmap_sem);
+
+ err = migrate_vmas(mm, from_nodes, to_nodes, flags);
+ if (err)
+ goto out;
+
+/*
+ * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
+ * bit in 'to' is not also set in 'tmp'. Clear the found 'source'
+ * bit in 'tmp', and return that <source, dest> pair for migration.
+ * The pair of nodemasks 'to' and 'from' define the map.
+ *
+ * If no pair of bits is found that way, fallback to picking some
+ * pair of 'source' and 'dest' bits that are not the same. If the
+ * 'source' and 'dest' bits are the same, this represents a node
+ * that will be migrating to itself, so no pages need move.
+ *
+ * If no bits are left in 'tmp', or if all remaining bits left
+ * in 'tmp' correspond to the same bit in 'to', return false
+ * (nothing left to migrate).
+ *
+ * This lets us pick a pair of nodes to migrate between, such that
+ * if possible the dest node is not already occupied by some other
+ * source node, minimizing the risk of overloading the memory on a
+ * node that would happen if we migrated incoming memory to a node
+ * before migrating outgoing memory source that same node.
+ *
+ * A single scan of tmp is sufficient. As we go, we remember the
+ * most recent <s, d> pair that moved (s != d). If we find a pair
+ * that not only moved, but what's better, moved to an empty slot
+ * (d is not set in tmp), then we break out then, with that pair.
+ * Otherwise when we finish scannng from_tmp, we at least have the
+ * most recent <s, d> pair that moved. If we get all the way through
+ * the scan of tmp without finding any node that moved, much less
+ * moved to an empty node, then there is nothing left worth migrating.
+ */
+
+ tmp = *from_nodes;
+ while (!nodes_empty(tmp)) {
+ int s,d;
+ int source = -1;
+ int dest = 0;
+
+ for_each_node_mask(s, tmp) {
+ d = node_remap(s, *from_nodes, *to_nodes);
+ if (s == d)
+ continue;
+
+ source = s; /* Node moved. Memorize */
+ dest = d;
+
+ /* dest not in remaining from nodes? */
+ if (!node_isset(dest, tmp))
+ break;
+ }
+ if (source == -1)
+ break;
+
+ node_clear(source, tmp);
+ err = migrate_to_node(mm, source, dest, flags);
+ if (err > 0)
+ busy += err;
+ if (err < 0)
+ break;
+ }
+out:
+ up_read(&mm->mmap_sem);
+ if (err < 0)
+ return err;
+ return busy;
+
+}
+
+static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
+{
+ struct vm_area_struct *vma = (struct vm_area_struct *)private;
+
+ return alloc_page_vma(GFP_HIGHUSER, vma, page_address_in_vma(page, vma));
+}
+#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;
+}
+
+static struct page *new_vma_page(struct page *page, unsigned long private)
+{
+ return NULL;
+}
+#endif
+
+long do_mbind(unsigned long start, unsigned long len,
+ unsigned long mode, nodemask_t *nmask, unsigned long flags)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+ struct mempolicy *new;
+ unsigned long end;
+ int err;
+ LIST_HEAD(pagelist);
+
+ if ((flags & ~(unsigned long)(MPOL_MF_STRICT |
+ MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
+ || mode > MPOL_MAX)
+ return -EINVAL;
+ if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
+ return -EPERM;
+
+ if (start & ~PAGE_MASK)
+ return -EINVAL;
+
+ if (mode == MPOL_DEFAULT)
+ flags &= ~MPOL_MF_STRICT;
+
+ len = (len + PAGE_SIZE - 1) & PAGE_MASK;
+ end = start + len;
+
+ if (end < start)
+ return -EINVAL;
+ if (end == start)
+ return 0;
+
+ if (mpol_check_policy(mode, nmask))
+ return -EINVAL;
+
+ new = mpol_new(mode, nmask);
+ if (IS_ERR(new))
+ return PTR_ERR(new);
+
+ /*
+ * If we are using the default policy then operation
+ * on discontinuous address spaces is okay after all
+ */
+ if (!new)
+ flags |= MPOL_MF_DISCONTIG_OK;
+
+ PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len,
+ mode,nodes_addr(nodes)[0]);
+
+ down_write(&mm->mmap_sem);
+ vma = check_range(mm, start, end, nmask,
+ flags | MPOL_MF_INVERT, &pagelist);
+
+ err = PTR_ERR(vma);
+ if (!IS_ERR(vma)) {
+ int nr_failed = 0;
+
+ err = mbind_range(vma, start, end, new);
+
+ if (!list_empty(&pagelist))
+ nr_failed = migrate_pages(&pagelist, new_vma_page,
+ (unsigned long)vma);
+
+ if (!err && nr_failed && (flags & MPOL_MF_STRICT))
+ err = -EIO;
}
- out:
- if (vma)
- up_read(¤t->mm->mmap_sem);
+ up_write(&mm->mmap_sem);
+ mpol_free(new);
+ return err;
+}
+
+/*
+ * User space interface with variable sized bitmaps for nodelists.
+ */
+
+/* Copy a node mask from user space. */
+static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
+ unsigned long maxnode)
+{
+ unsigned long k;
+ unsigned long nlongs;
+ unsigned long endmask;
+
+ --maxnode;
+ nodes_clear(*nodes);
+ if (maxnode == 0 || !nmask)
+ return 0;
+ if (maxnode > PAGE_SIZE*BITS_PER_BYTE)
+ return -EINVAL;
+
+ nlongs = BITS_TO_LONGS(maxnode);
+ if ((maxnode % BITS_PER_LONG) == 0)
+ endmask = ~0UL;
+ else
+ endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
+
+ /* When the user specified more nodes than supported just check
+ if the non supported part is all zero. */
+ if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
+ if (nlongs > PAGE_SIZE/sizeof(long))
+ return -EINVAL;
+ for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
+ unsigned long t;
+ if (get_user(t, nmask + k))
+ return -EFAULT;
+ if (k == nlongs - 1) {
+ if (t & endmask)
+ return -EINVAL;
+ } else if (t)
+ return -EINVAL;
+ }
+ nlongs = BITS_TO_LONGS(MAX_NUMNODES);
+ endmask = ~0UL;
+ }
+
+ if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long)))
+ return -EFAULT;
+ nodes_addr(*nodes)[nlongs-1] &= endmask;
+ return 0;
+}
+
+/* Copy a kernel node mask to user space */
+static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
+ nodemask_t *nodes)
+{
+ unsigned long copy = ALIGN(maxnode-1, 64) / 8;
+ const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long);
+
+ if (copy > nbytes) {
+ if (copy > PAGE_SIZE)
+ return -EINVAL;
+ if (clear_user((char __user *)mask + nbytes, copy - nbytes))
+ return -EFAULT;
+ copy = nbytes;
+ }
+ return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
+}
+
+asmlinkage long sys_mbind(unsigned long start, unsigned long len,
+ unsigned long mode,
+ unsigned long __user *nmask, unsigned long maxnode,
+ unsigned flags)
+{
+ nodemask_t nodes;
+ int err;
+
+ err = get_nodes(&nodes, nmask, maxnode);
+ if (err)
+ return err;
+ return do_mbind(start, len, mode, &nodes, flags);
+}
+
+/* Set the process memory policy */
+asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
+ unsigned long maxnode)
+{
+ int err;
+ nodemask_t nodes;
+
+ if (mode < 0 || mode > MPOL_MAX)
+ return -EINVAL;
+ err = get_nodes(&nodes, nmask, maxnode);
+ if (err)
+ return err;
+ return do_set_mempolicy(mode, &nodes);
+}
+
+asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
+ const unsigned long __user *old_nodes,
+ const unsigned long __user *new_nodes)
+{
+ struct mm_struct *mm;
+ struct task_struct *task;
+ nodemask_t old;
+ nodemask_t new;
+ nodemask_t task_nodes;
+ int err;
+
+ err = get_nodes(&old, old_nodes, maxnode);
+ if (err)
+ return err;
+
+ err = get_nodes(&new, new_nodes, maxnode);
+ if (err)
+ return err;
+
+ /* Find the mm_struct */
+ read_lock(&tasklist_lock);
+ task = pid ? find_task_by_pid(pid) : current;
+ if (!task) {
+ read_unlock(&tasklist_lock);
+ return -ESRCH;
+ }
+ mm = get_task_mm(task);
+ read_unlock(&tasklist_lock);
+
+ if (!mm)
+ return -EINVAL;
+
+ /*
+ * 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
+ * userid as the target process.
+ */
+ if ((current->euid != task->suid) && (current->euid != task->uid) &&
+ (current->uid != task->suid) && (current->uid != task->uid) &&
+ !capable(CAP_SYS_NICE)) {
+ err = -EPERM;
+ goto out;
+ }
+
+ task_nodes = cpuset_mems_allowed(task);
+ /* Is the user allowed to access the target nodes? */
+ if (!nodes_subset(new, task_nodes) && !capable(CAP_SYS_NICE)) {
+ err = -EPERM;
+ goto out;
+ }
+
+ err = security_task_movememory(task);
+ if (err)
+ goto out;
+
+ err = do_migrate_pages(mm, &old, &new,
+ capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE);
+out:
+ mmput(mm);
+ return err;
+}
+
+
+/* Retrieve NUMA policy */
+asmlinkage long sys_get_mempolicy(int __user *policy,
+ unsigned long __user *nmask,
+ unsigned long maxnode,
+ unsigned long addr, unsigned long flags)
+{
+ int err, pval;
+ nodemask_t nodes;
+
+ if (nmask != NULL && maxnode < MAX_NUMNODES)
+ return -EINVAL;
+
+ err = do_get_mempolicy(&pval, &nodes, addr, flags);
+
+ if (err)
+ return err;
+
+ if (policy && put_user(pval, policy))
+ return -EFAULT;
+
+ if (nmask)
+ err = copy_nodes_to_user(nmask, maxnode, &nodes);
+
return err;
}
#ifdef CONFIG_COMPAT
-/* The other functions are compatible */
-asmlinkage long compat_get_mempolicy(int __user *policy,
- unsigned __user *nmask, unsigned maxnode,
- unsigned addr, unsigned flags)
+
+asmlinkage long compat_sys_get_mempolicy(int __user *policy,
+ compat_ulong_t __user *nmask,
+ compat_ulong_t maxnode,
+ compat_ulong_t addr, compat_ulong_t flags)
{
long err;
unsigned long __user *nm = NULL;
+ unsigned long nr_bits, alloc_size;
+ DECLARE_BITMAP(bm, MAX_NUMNODES);
+
+ nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
+ alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
+
if (nmask)
- nm = compat_alloc_user_space(ALIGN(maxnode-1, 64) / 8);
- err = sys_get_mempolicy(policy, nm, maxnode, addr, flags);
- if (!err && copy_in_user(nmask, nm, ALIGN(maxnode-1, 32)/8))
- err = -EFAULT;
+ nm = compat_alloc_user_space(alloc_size);
+
+ err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags);
+
+ if (!err && nmask) {
+ err = copy_from_user(bm, nm, alloc_size);
+ /* ensure entire bitmap is zeroed */
+ err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8);
+ err |= compat_put_bitmap(nmask, bm, nr_bits);
+ }
+
return err;
}
+
+asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
+ compat_ulong_t maxnode)
+{
+ long err = 0;
+ unsigned long __user *nm = NULL;
+ unsigned long nr_bits, alloc_size;
+ DECLARE_BITMAP(bm, MAX_NUMNODES);
+
+ nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
+ alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
+
+ if (nmask) {
+ err = compat_get_bitmap(bm, nmask, nr_bits);
+ nm = compat_alloc_user_space(alloc_size);
+ err |= copy_to_user(nm, bm, alloc_size);
+ }
+
+ if (err)
+ return -EFAULT;
+
+ return sys_set_mempolicy(mode, nm, nr_bits+1);
+}
+
+asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
+ compat_ulong_t mode, compat_ulong_t __user *nmask,
+ compat_ulong_t maxnode, compat_ulong_t flags)
+{
+ long err = 0;
+ unsigned long __user *nm = NULL;
+ unsigned long nr_bits, alloc_size;
+ nodemask_t bm;
+
+ nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
+ alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
+
+ if (nmask) {
+ err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits);
+ nm = compat_alloc_user_space(alloc_size);
+ err |= copy_to_user(nm, nodes_addr(bm), alloc_size);
+ }
+
+ if (err)
+ return -EFAULT;
+
+ return sys_mbind(start, len, mode, nm, nr_bits+1, flags);
+}
+
#endif
/* Return effective policy for a VMA */
-static struct mempolicy *
-get_vma_policy(struct vm_area_struct *vma, unsigned long addr)
+static struct mempolicy * get_vma_policy(struct task_struct *task,
+ struct vm_area_struct *vma, unsigned long addr)
{
- struct mempolicy *pol = current->mempolicy;
+ struct mempolicy *pol = task->mempolicy;
if (vma) {
if (vma->vm_ops && vma->vm_ops->get_policy)
- pol = vma->vm_ops->get_policy(vma, addr);
+ pol = vma->vm_ops->get_policy(vma, addr);
else if (vma->vm_policy &&
vma->vm_policy->policy != MPOL_DEFAULT)
pol = vma->vm_policy;
}
/* Return a zonelist representing a mempolicy */
-static struct zonelist *zonelist_policy(unsigned gfp, struct mempolicy *policy)
+static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy)
{
int nd;
break;
case MPOL_BIND:
/* Lower zones don't get a policy applied */
- if (gfp >= policy_zone)
- return policy->v.zonelist;
+ /* Careful: current->mems_allowed might have moved */
+ if (gfp_zone(gfp) >= policy_zone)
+ if (cpuset_zonelist_valid_mems_allowed(policy->v.zonelist))
+ return policy->v.zonelist;
/*FALL THROUGH*/
case MPOL_INTERLEAVE: /* should not happen */
case MPOL_DEFAULT:
nd = 0;
BUG();
}
- return NODE_DATA(nd)->node_zonelists + (gfp & GFP_ZONEMASK);
+ return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp);
}
/* Do dynamic interleaving for a process */
struct task_struct *me = current;
nid = me->il_next;
- BUG_ON(nid >= MAX_NUMNODES);
- next = find_next_bit(policy->v.nodes, MAX_NUMNODES, 1+nid);
+ next = next_node(nid, policy->v.nodes);
if (next >= MAX_NUMNODES)
- next = find_first_bit(policy->v.nodes, MAX_NUMNODES);
+ next = first_node(policy->v.nodes);
me->il_next = next;
return nid;
}
+/*
+ * Depending on the memory policy provide a node from which to allocate the
+ * next slab entry.
+ */
+unsigned slab_node(struct mempolicy *policy)
+{
+ switch (policy->policy) {
+ case MPOL_INTERLEAVE:
+ return interleave_nodes(policy);
+
+ case MPOL_BIND:
+ /*
+ * Follow bind policy behavior and start allocation at the
+ * first node.
+ */
+ return policy->v.zonelist->zones[0]->zone_pgdat->node_id;
+
+ case MPOL_PREFERRED:
+ if (policy->v.preferred_node >= 0)
+ return policy->v.preferred_node;
+ /* Fall through */
+
+ default:
+ return numa_node_id();
+ }
+}
+
/* Do static interleaving for a VMA with known offset. */
static unsigned offset_il_node(struct mempolicy *pol,
struct vm_area_struct *vma, unsigned long off)
{
- unsigned nnodes = bitmap_weight(pol->v.nodes, MAX_NUMNODES);
+ unsigned nnodes = nodes_weight(pol->v.nodes);
unsigned target = (unsigned)off % nnodes;
int c;
int nid = -1;
c = 0;
do {
- nid = find_next_bit(pol->v.nodes, MAX_NUMNODES, nid+1);
+ nid = next_node(nid, pol->v.nodes);
c++;
} while (c <= target);
- BUG_ON(nid >= MAX_NUMNODES);
- BUG_ON(!test_bit(nid, pol->v.nodes));
return nid;
}
+/* Determine a node number for interleave */
+static inline unsigned interleave_nid(struct mempolicy *pol,
+ struct vm_area_struct *vma, unsigned long addr, int shift)
+{
+ if (vma) {
+ unsigned long off;
+
+ /*
+ * for small pages, there is no difference between
+ * shift and PAGE_SHIFT, so the bit-shift is safe.
+ * for huge pages, since vm_pgoff is in units of small
+ * pages, we need to shift off the always 0 bits to get
+ * a useful offset.
+ */
+ BUG_ON(shift < PAGE_SHIFT);
+ off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
+ off += (addr - vma->vm_start) >> shift;
+ return offset_il_node(pol, vma, off);
+ } else
+ return interleave_nodes(pol);
+}
+
+#ifdef CONFIG_HUGETLBFS
+/* Return a zonelist suitable for a huge page allocation. */
+struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr)
+{
+ struct mempolicy *pol = get_vma_policy(current, vma, addr);
+
+ if (pol->policy == MPOL_INTERLEAVE) {
+ unsigned nid;
+
+ nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
+ return NODE_DATA(nid)->node_zonelists + gfp_zone(GFP_HIGHUSER);
+ }
+ return zonelist_policy(GFP_HIGHUSER, pol);
+}
+#endif
+
/* Allocate a page in interleaved policy.
Own path because it needs to do special accounting. */
-static struct page *alloc_page_interleave(unsigned gfp, unsigned order, unsigned nid)
+static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
+ unsigned nid)
{
struct zonelist *zl;
struct page *page;
- BUG_ON(!test_bit(nid, node_online_map));
- zl = NODE_DATA(nid)->node_zonelists + (gfp & GFP_ZONEMASK);
+ zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
page = __alloc_pages(gfp, order, zl);
- if (page && page_zone(page) == zl->zones[0]) {
- zl->zones[0]->pageset[get_cpu()].interleave_hit++;
- put_cpu();
- }
+ if (page && page_zone(page) == zl->zones[0])
+ inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
return page;
}
* Should be called with the mm_sem of the vma hold.
*/
struct page *
-alloc_page_vma(unsigned gfp, struct vm_area_struct *vma, unsigned long addr)
+alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
{
- struct mempolicy *pol = get_vma_policy(vma, addr);
+ struct mempolicy *pol = get_vma_policy(current, vma, addr);
+
+ cpuset_update_task_memory_state();
if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
unsigned nid;
- if (vma) {
- unsigned long off;
- BUG_ON(addr >= vma->vm_end);
- BUG_ON(addr < vma->vm_start);
- off = vma->vm_pgoff;
- off += (addr - vma->vm_start) >> PAGE_SHIFT;
- nid = offset_il_node(pol, vma, off);
- } else {
- /* fall back to process interleaving */
- nid = interleave_nodes(pol);
- }
+
+ nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
return alloc_page_interleave(gfp, 0, nid);
}
return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol));
* Allocate a page from the kernel page pool. When not in
* interrupt context and apply the current process NUMA policy.
* Returns NULL when no page can be allocated.
+ *
+ * Don't call cpuset_update_task_memory_state() unless
+ * 1) it's ok to take cpuset_sem (can WAIT), and
+ * 2) allocating for current task (not interrupt).
*/
-struct page *alloc_pages_current(unsigned gfp, unsigned order)
+struct page *alloc_pages_current(gfp_t gfp, unsigned order)
{
struct mempolicy *pol = current->mempolicy;
+ if ((gfp & __GFP_WAIT) && !in_interrupt())
+ cpuset_update_task_memory_state();
if (!pol || in_interrupt())
pol = &default_policy;
if (pol->policy == MPOL_INTERLEAVE)
}
EXPORT_SYMBOL(alloc_pages_current);
+/*
+ * If mpol_copy() sees current->cpuset == cpuset_being_rebound, then it
+ * rebinds the mempolicy its copying by calling mpol_rebind_policy()
+ * with the mems_allowed returned by cpuset_mems_allowed(). This
+ * keeps mempolicies cpuset relative after its cpuset moves. See
+ * further kernel/cpuset.c update_nodemask().
+ */
+void *cpuset_being_rebound;
+
/* Slow path of a mempolicy copy */
struct mempolicy *__mpol_copy(struct mempolicy *old)
{
if (!new)
return ERR_PTR(-ENOMEM);
+ if (current_cpuset_is_being_rebound()) {
+ nodemask_t mems = cpuset_mems_allowed(current);
+ mpol_rebind_policy(old, &mems);
+ }
*new = *old;
atomic_set(&new->refcnt, 1);
if (new->policy == MPOL_BIND) {
case MPOL_DEFAULT:
return 1;
case MPOL_INTERLEAVE:
- return bitmap_equal(a->v.nodes, b->v.nodes, MAX_NUMNODES);
+ return nodes_equal(a->v.nodes, b->v.nodes);
case MPOL_PREFERRED:
return a->v.preferred_node == b->v.preferred_node;
case MPOL_BIND: {
kmem_cache_free(policy_cache, p);
}
-/*
- * Hugetlb policy. Same as above, just works with node numbers instead of
- * zonelists.
- */
-
-/* Find first node suitable for an allocation */
-int mpol_first_node(struct vm_area_struct *vma, unsigned long addr)
-{
- struct mempolicy *pol = get_vma_policy(vma, addr);
-
- switch (pol->policy) {
- case MPOL_DEFAULT:
- return numa_node_id();
- case MPOL_BIND:
- return pol->v.zonelist->zones[0]->zone_pgdat->node_id;
- case MPOL_INTERLEAVE:
- return interleave_nodes(pol);
- case MPOL_PREFERRED:
- return pol->v.preferred_node >= 0 ?
- pol->v.preferred_node : numa_node_id();
- }
- BUG();
- return 0;
-}
-
-/* Find secondary valid nodes for an allocation */
-int mpol_node_valid(int nid, struct vm_area_struct *vma, unsigned long addr)
-{
- struct mempolicy *pol = get_vma_policy(vma, addr);
-
- switch (pol->policy) {
- case MPOL_PREFERRED:
- case MPOL_DEFAULT:
- case MPOL_INTERLEAVE:
- return 1;
- case MPOL_BIND: {
- struct zone **z;
- for (z = pol->v.zonelist->zones; *z; z++)
- if ((*z)->zone_pgdat->node_id == nid)
- return 1;
- return 0;
- }
- default:
- BUG();
- return 0;
- }
-}
-
/*
* Shared memory backing store policy support.
*
* Remember policies even when nobody has shared memory mapped.
* The policies are kept in Red-Black tree linked from the inode.
- * They are protected by the sp->sem semaphore, which should be held
+ * They are protected by the sp->lock spinlock, which should be held
* for any accesses to the tree.
*/
/* lookup first element intersecting start-end */
-/* Caller holds sp->sem */
+/* Caller holds sp->lock */
static struct sp_node *
sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
{
while (n) {
struct sp_node *p = rb_entry(n, struct sp_node, nd);
- if (start >= p->end) {
+
+ if (start >= p->end)
n = n->rb_right;
- } else if (end < p->start) {
+ else if (end <= p->start)
n = n->rb_left;
- } else {
+ else
break;
- }
}
if (!n)
return NULL;
}
/* Insert a new shared policy into the list. */
-/* Caller holds sp->sem */
+/* Caller holds sp->lock */
static void sp_insert(struct shared_policy *sp, struct sp_node *new)
{
struct rb_node **p = &sp->root.rb_node;
struct mempolicy *pol = NULL;
struct sp_node *sn;
- down(&sp->sem);
+ if (!sp->root.rb_node)
+ return NULL;
+ spin_lock(&sp->lock);
sn = sp_lookup(sp, idx, idx+1);
if (sn) {
mpol_get(sn->policy);
pol = sn->policy;
}
- up(&sp->sem);
+ spin_unlock(&sp->lock);
return pol;
}
static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
unsigned long end, struct sp_node *new)
{
- struct sp_node *n, *new2;
+ struct sp_node *n, *new2 = NULL;
- down(&sp->sem);
+restart:
+ spin_lock(&sp->lock);
n = sp_lookup(sp, start, end);
/* Take care of old policies in the same range. */
while (n && n->start < end) {
} else {
/* Old policy spanning whole new range. */
if (n->end > end) {
- new2 = sp_alloc(end, n->end, n->policy);
if (!new2) {
- up(&sp->sem);
- return -ENOMEM;
+ spin_unlock(&sp->lock);
+ new2 = sp_alloc(end, n->end, n->policy);
+ if (!new2)
+ return -ENOMEM;
+ goto restart;
}
- n->end = end;
+ n->end = start;
sp_insert(sp, new2);
- }
- /* Old crossing beginning, but not end (easy) */
- if (n->start < start && n->end > start)
+ new2 = NULL;
+ break;
+ } else
n->end = start;
}
if (!next)
}
if (new)
sp_insert(sp, new);
- up(&sp->sem);
+ spin_unlock(&sp->lock);
+ if (new2) {
+ mpol_free(new2->policy);
+ kmem_cache_free(sn_cache, new2);
+ }
return 0;
}
+void mpol_shared_policy_init(struct shared_policy *info, int policy,
+ nodemask_t *policy_nodes)
+{
+ info->root = RB_ROOT;
+ spin_lock_init(&info->lock);
+
+ if (policy != MPOL_DEFAULT) {
+ struct mempolicy *newpol;
+
+ /* Falls back to MPOL_DEFAULT on any error */
+ newpol = mpol_new(policy, policy_nodes);
+ if (!IS_ERR(newpol)) {
+ /* Create pseudo-vma that contains just the policy */
+ struct vm_area_struct pvma;
+
+ memset(&pvma, 0, sizeof(struct vm_area_struct));
+ /* Policy covers entire file */
+ pvma.vm_end = TASK_SIZE;
+ mpol_set_shared_policy(info, &pvma, newpol);
+ mpol_free(newpol);
+ }
+ }
+}
+
int mpol_set_shared_policy(struct shared_policy *info,
struct vm_area_struct *vma, struct mempolicy *npol)
{
PDprintk("set_shared_policy %lx sz %lu %d %lx\n",
vma->vm_pgoff,
sz, npol? npol->policy : -1,
- npol ? npol->v.nodes[0] : -1);
+ npol ? nodes_addr(npol->v.nodes)[0] : -1);
if (npol) {
new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
struct sp_node *n;
struct rb_node *next;
- down(&p->sem);
+ if (!p->root.rb_node)
+ return;
+ spin_lock(&p->lock);
next = rb_first(&p->root);
while (next) {
n = rb_entry(next, struct sp_node, nd);
mpol_free(n->policy);
kmem_cache_free(sn_cache, n);
}
- up(&p->sem);
+ spin_unlock(&p->lock);
}
/* assumes fs == KERNEL_DS */
/* Set interleaving policy for system init. This way not all
the data structures allocated at system boot end up in node zero. */
- if (sys_set_mempolicy(MPOL_INTERLEAVE, node_online_map, MAX_NUMNODES) < 0)
+ if (do_set_mempolicy(MPOL_INTERLEAVE, &node_online_map))
printk("numa_policy_init: interleaving failed\n");
}
-/* Reset policy of current process to default.
- * Assumes fs == KERNEL_DS */
+/* Reset policy of current process to default */
void numa_default_policy(void)
{
- sys_set_mempolicy(MPOL_DEFAULT, NULL, 0);
+ do_set_mempolicy(MPOL_DEFAULT, NULL);
+}
+
+/* Migrate a policy to a different set of nodes */
+void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask)
+{
+ nodemask_t *mpolmask;
+ nodemask_t tmp;
+
+ if (!pol)
+ return;
+ mpolmask = &pol->cpuset_mems_allowed;
+ if (nodes_equal(*mpolmask, *newmask))
+ return;
+
+ switch (pol->policy) {
+ case MPOL_DEFAULT:
+ break;
+ case MPOL_INTERLEAVE:
+ nodes_remap(tmp, pol->v.nodes, *mpolmask, *newmask);
+ pol->v.nodes = tmp;
+ *mpolmask = *newmask;
+ current->il_next = node_remap(current->il_next,
+ *mpolmask, *newmask);
+ break;
+ case MPOL_PREFERRED:
+ pol->v.preferred_node = node_remap(pol->v.preferred_node,
+ *mpolmask, *newmask);
+ *mpolmask = *newmask;
+ break;
+ case MPOL_BIND: {
+ nodemask_t nodes;
+ struct zone **z;
+ struct zonelist *zonelist;
+
+ nodes_clear(nodes);
+ for (z = pol->v.zonelist->zones; *z; z++)
+ node_set((*z)->zone_pgdat->node_id, nodes);
+ nodes_remap(tmp, nodes, *mpolmask, *newmask);
+ nodes = tmp;
+
+ zonelist = bind_zonelist(&nodes);
+
+ /* If no mem, then zonelist is NULL and we keep old zonelist.
+ * If that old zonelist has no remaining mems_allowed nodes,
+ * then zonelist_policy() will "FALL THROUGH" to MPOL_DEFAULT.
+ */
+
+ if (zonelist) {
+ /* Good - got mem - substitute new zonelist */
+ kfree(pol->v.zonelist);
+ pol->v.zonelist = zonelist;
+ }
+ *mpolmask = *newmask;
+ break;
+ }
+ default:
+ BUG();
+ break;
+ }
+}
+
+/*
+ * Wrapper for mpol_rebind_policy() that just requires task
+ * pointer, and updates task mempolicy.
+ */
+
+void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
+{
+ mpol_rebind_policy(tsk->mempolicy, new);
+}
+
+/*
+ * Rebind each vma in mm to new nodemask.
+ *
+ * Call holding a reference to mm. Takes mm->mmap_sem during call.
+ */
+
+void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
+{
+ struct vm_area_struct *vma;
+
+ down_write(&mm->mmap_sem);
+ for (vma = mm->mmap; vma; vma = vma->vm_next)
+ mpol_rebind_policy(vma->vm_policy, new);
+ up_write(&mm->mmap_sem);
+}
+
+/*
+ * Display pages allocated per node and memory policy via /proc.
+ */
+
+static const char *policy_types[] = { "default", "prefer", "bind",
+ "interleave" };
+
+/*
+ * Convert a mempolicy into a string.
+ * Returns the number of characters in buffer (if positive)
+ * or an error (negative)
+ */
+static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
+{
+ char *p = buffer;
+ int l;
+ nodemask_t nodes;
+ int mode = pol ? pol->policy : MPOL_DEFAULT;
+
+ switch (mode) {
+ case MPOL_DEFAULT:
+ nodes_clear(nodes);
+ break;
+
+ case MPOL_PREFERRED:
+ nodes_clear(nodes);
+ node_set(pol->v.preferred_node, nodes);
+ break;
+
+ case MPOL_BIND:
+ get_zonemask(pol, &nodes);
+ break;
+
+ case MPOL_INTERLEAVE:
+ nodes = pol->v.nodes;
+ break;
+
+ default:
+ BUG();
+ return -EFAULT;
+ }
+
+ l = strlen(policy_types[mode]);
+ if (buffer + maxlen < p + l + 1)
+ return -ENOSPC;
+
+ strcpy(p, policy_types[mode]);
+ p += l;
+
+ if (!nodes_empty(nodes)) {
+ if (buffer + maxlen < p + 2)
+ return -ENOSPC;
+ *p++ = '=';
+ p += nodelist_scnprintf(p, buffer + maxlen - p, nodes);
+ }
+ return p - buffer;
+}
+
+struct numa_maps {
+ unsigned long pages;
+ unsigned long anon;
+ unsigned long active;
+ unsigned long writeback;
+ unsigned long mapcount_max;
+ unsigned long dirty;
+ unsigned long swapcache;
+ unsigned long node[MAX_NUMNODES];
+};
+
+static void gather_stats(struct page *page, void *private, int pte_dirty)
+{
+ struct numa_maps *md = private;
+ int count = page_mapcount(page);
+
+ md->pages++;
+ if (pte_dirty || PageDirty(page))
+ md->dirty++;
+
+ if (PageSwapCache(page))
+ md->swapcache++;
+
+ if (PageActive(page))
+ md->active++;
+
+ if (PageWriteback(page))
+ md->writeback++;
+
+ if (PageAnon(page))
+ md->anon++;
+
+ if (count > md->mapcount_max)
+ md->mapcount_max = count;
+
+ md->node[page_to_nid(page)]++;
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+static void check_huge_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end,
+ struct numa_maps *md)
+{
+ unsigned long addr;
+ struct page *page;
+
+ for (addr = start; addr < end; addr += HPAGE_SIZE) {
+ pte_t *ptep = huge_pte_offset(vma->vm_mm, addr & HPAGE_MASK);
+ pte_t pte;
+
+ if (!ptep)
+ continue;
+
+ pte = *ptep;
+ if (pte_none(pte))
+ continue;
+
+ page = pte_page(pte);
+ if (!page)
+ continue;
+
+ gather_stats(page, md, pte_dirty(*ptep));
+ }
+}
+#else
+static inline void check_huge_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end,
+ struct numa_maps *md)
+{
+}
+#endif
+
+int show_numa_map(struct seq_file *m, void *v)
+{
+ struct proc_maps_private *priv = m->private;
+ struct vm_area_struct *vma = v;
+ struct numa_maps *md;
+ struct file *file = vma->vm_file;
+ struct mm_struct *mm = vma->vm_mm;
+ int n;
+ char buffer[50];
+
+ if (!mm)
+ return 0;
+
+ md = kzalloc(sizeof(struct numa_maps), GFP_KERNEL);
+ if (!md)
+ return 0;
+
+ mpol_to_str(buffer, sizeof(buffer),
+ get_vma_policy(priv->task, vma, vma->vm_start));
+
+ seq_printf(m, "%08lx %s", vma->vm_start, buffer);
+
+ if (file) {
+ seq_printf(m, " file=");
+ seq_path(m, file->f_vfsmnt, file->f_dentry, "\n\t= ");
+ } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
+ seq_printf(m, " heap");
+ } else if (vma->vm_start <= mm->start_stack &&
+ vma->vm_end >= mm->start_stack) {
+ seq_printf(m, " stack");
+ }
+
+ if (is_vm_hugetlb_page(vma)) {
+ check_huge_range(vma, vma->vm_start, vma->vm_end, md);
+ seq_printf(m, " huge");
+ } else {
+ check_pgd_range(vma, vma->vm_start, vma->vm_end,
+ &node_online_map, MPOL_MF_STATS, md);
+ }
+
+ if (!md->pages)
+ goto out;
+
+ if (md->anon)
+ seq_printf(m," anon=%lu",md->anon);
+
+ if (md->dirty)
+ seq_printf(m," dirty=%lu",md->dirty);
+
+ if (md->pages != md->anon && md->pages != md->dirty)
+ seq_printf(m, " mapped=%lu", md->pages);
+
+ if (md->mapcount_max > 1)
+ seq_printf(m, " mapmax=%lu", md->mapcount_max);
+
+ if (md->swapcache)
+ seq_printf(m," swapcache=%lu", md->swapcache);
+
+ if (md->active < md->pages && !is_vm_hugetlb_page(vma))
+ seq_printf(m," active=%lu", md->active);
+
+ if (md->writeback)
+ seq_printf(m," writeback=%lu", md->writeback);
+
+ for_each_online_node(n)
+ if (md->node[n])
+ seq_printf(m, " N%d=%lu", n, md->node[n]);
+out:
+ seq_putc(m, '\n');
+ kfree(md);
+
+ if (m->count < m->size)
+ m->version = (vma != priv->tail_vma) ? vma->vm_start : 0;
+ return 0;
}
+