linux/mm/mempolicy.c

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/*
* 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
* be allocated.
*
* Support four policies per VMA and per process:
*
* The VMA policy has priority over the process policy for a page fault.
*
* interleave Allocate memory interleaved over a set of nodes,
* with normal fallback if it fails.
* For VMA based allocations this interleaves based on the
* 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.
*
* The process policy is applied for most non interrupt memory allocations
* in that process' context. Interrupts ignore the policies and always
* try to allocate on the local CPU. The VMA policy is only applied for memory
* allocations for a VMA in the VM.
*
* Currently there are a few corner cases in swapping where the policy
* is not applied, but the majority should be handled. When process policy
* is used it is not remembered over swap outs/swap ins.
*
* Only the highest zone in the zone hierarchy gets policied. Allocations
* requesting a lower zone just use default policy. This implies that
* on systems with highmem kernel lowmem allocation don't get policied.
* Same with GFP_DMA allocations.
*
* For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between
* all users and remembered even when nobody has memory mapped.
*/
/* Notebook:
fix mmap readahead to honour policy and enable policy for any page cache
object
statistics for bigpages
global policy for page cache? currently it uses process policy. Requires
first item above.
handle mremap for shared memory (currently ignored for the policy)
grows down?
make bind policy root only? It can trigger oom much faster and the
kernel is not always grateful with that.
could replace all the switch()es with a mempolicy_ops structure.
*/
#include <linux/mempolicy.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/hugetlb.h>
#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/module.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/compat.h>
#include <linux/mempolicy.h>
#include <linux/swap.h>
#include <asm/tlbflush.h>
#include <asm/uaccess.h>
/* Internal MPOL_MF_xxx flags */
#define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
static kmem_cache_t *policy_cache;
static kmem_cache_t *sn_cache;
#define PDprintk(fmt...)
/* Highest zone. An specific allocation for a zone below that is not
policied. */
int policy_zone = ZONE_DMA;
struct mempolicy default_policy = {
.refcnt = ATOMIC_INIT(1), /* never free it */
.policy = MPOL_DEFAULT,
};
/* Do sanity checking on a policy */
static int mpol_check_policy(int mode, nodemask_t *nodes)
{
int empty = nodes_empty(*nodes);
switch (mode) {
case MPOL_DEFAULT:
if (!empty)
return -EINVAL;
break;
case MPOL_BIND:
case MPOL_INTERLEAVE:
/* Preferred will only use the first bit, but allow
more for now. */
if (empty)
return -EINVAL;
break;
}
return nodes_subset(*nodes, node_online_map) ? 0 : -EINVAL;
}
/* Generate a custom zonelist for the BIND policy. */
static struct zonelist *bind_zonelist(nodemask_t *nodes)
{
struct zonelist *zl;
int num, max, nd;
max = 1 + MAX_NR_ZONES * nodes_weight(*nodes);
zl = kmalloc(sizeof(void *) * max, GFP_KERNEL);
if (!zl)
return NULL;
num = 0;
for_each_node_mask(nd, *nodes)
zl->zones[num++] = &NODE_DATA(nd)->node_zones[policy_zone];
zl->zones[num] = NULL;
return zl;
}
/* Create a new policy */
static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
{
struct mempolicy *policy;
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);
if (!policy)
return ERR_PTR(-ENOMEM);
atomic_set(&policy->refcnt, 1);
switch (mode) {
case MPOL_INTERLEAVE:
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 = first_node(*nodes);
if (policy->v.preferred_node >= MAX_NUMNODES)
policy->v.preferred_node = -1;
break;
case MPOL_BIND:
policy->v.zonelist = bind_zonelist(nodes);
if (policy->v.zonelist == NULL) {
kmem_cache_free(policy_cache, policy);
return ERR_PTR(-ENOMEM);
}
break;
}
policy->policy = mode;
return policy;
}
/* Check if we are the only process mapping the page in question */
static inline int single_mm_mapping(struct mm_struct *mm,
struct address_space *mapping)
{
struct vm_area_struct *vma;
struct prio_tree_iter iter;
int rc = 1;
spin_lock(&mapping->i_mmap_lock);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX)
if (mm != vma->vm_mm) {
rc = 0;
goto out;
}
list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list)
if (mm != vma->vm_mm) {
rc = 0;
goto out;
}
out:
spin_unlock(&mapping->i_mmap_lock);
return rc;
}
/*
* Add a page to be migrated to the pagelist
*/
static void migrate_page_add(struct vm_area_struct *vma,
struct page *page, struct list_head *pagelist, unsigned long flags)
{
/*
* Avoid migrating a page that is shared by others and not writable.
*/
if ((flags & MPOL_MF_MOVE_ALL) || !page->mapping || PageAnon(page) ||
mapping_writably_mapped(page->mapping) ||
single_mm_mapping(vma->vm_mm, page->mapping)) {
int rc = isolate_lru_page(page);
if (rc == 1)
list_add(&page->lru, pagelist);
/*
* If the isolate attempt was not successful then we just
* encountered an unswappable page. Something must be wrong.
*/
WARN_ON(rc == 0);
}
}
/* Ensure all existing pages follow the policy. */
2005-10-30 01:16:12 +00:00
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,
struct list_head *pagelist)
{
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;
page = vm_normal_page(vma, addr, *pte);
if (!page)
continue;
nid = page_to_nid(page);
if (!node_isset(nid, *nodes)) {
if (pagelist)
migrate_page_add(vma, page, pagelist, flags);
else
break;
}
} while (pte++, addr += PAGE_SIZE, addr != end);
pte_unmap_unlock(orig_pte, ptl);
return addr != end;
}
2005-10-30 01:16:12 +00:00
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,
struct list_head *pagelist)
{
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, pagelist))
return -EIO;
} while (pmd++, addr = next, addr != end);
return 0;
}
2005-10-30 01:16:12 +00:00
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,
struct list_head *pagelist)
{
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, pagelist))
return -EIO;
} while (pud++, addr = next, addr != end);
return 0;
}
2005-10-30 01:16:12 +00:00
static inline int check_pgd_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long end,
const nodemask_t *nodes, unsigned long flags,
struct list_head *pagelist)
{
pgd_t *pgd;
unsigned long next;
2005-10-30 01:16:12 +00:00
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, pagelist))
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))
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,
const nodemask_t *nodes, unsigned long flags,
struct list_head *pagelist)
{
int err;
struct vm_area_struct *first, *vma, *prev;
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 (!(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, pagelist);
if (err) {
first = ERR_PTR(err);
break;
}
}
prev = vma;
}
return first;
}
/* Apply policy to a single VMA */
static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new)
{
int err = 0;
struct mempolicy *old = vma->vm_policy;
PDprintk("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
vma->vm_start, vma->vm_end, vma->vm_pgoff,
vma->vm_ops, vma->vm_file,
vma->vm_ops ? vma->vm_ops->set_policy : NULL);
if (vma->vm_ops && vma->vm_ops->set_policy)
err = vma->vm_ops->set_policy(vma, new);
if (!err) {
mpol_get(new);
vma->vm_policy = new;
mpol_free(old);
}
return err;
}
/* Step 2: apply policy to a range and do splits. */
static int mbind_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct mempolicy *new)
{
struct vm_area_struct *next;
int err;
err = 0;
for (; vma && vma->vm_start < end; vma = next) {
next = vma->vm_next;
if (vma->vm_start < start)
err = split_vma(vma->vm_mm, vma, start, 1);
if (!err && vma->vm_end > end)
err = split_vma(vma->vm_mm, vma, end, 0);
if (!err)
err = policy_vma(vma, new);
if (err)
break;
}
return err;
}
static int contextualize_policy(int mode, nodemask_t *nodes)
{
if (!nodes)
return 0;
/* Update current mems_allowed */
cpuset_update_current_mems_allowed();
/* Ignore nodes not set in current->mems_allowed */
cpuset_restrict_to_mems_allowed(nodes->bits);
return mpol_check_policy(mode, nodes);
}
static int swap_pages(struct list_head *pagelist)
{
LIST_HEAD(moved);
LIST_HEAD(failed);
int n;
n = migrate_pages(pagelist, NULL, &moved, &failed);
putback_lru_pages(&failed);
putback_lru_pages(&moved);
return n;
}
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_RESOURCE))
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,
(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) ? &pagelist : NULL);
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 = swap_pages(&pagelist);
if (!err && nr_failed && (flags & MPOL_MF_STRICT))
err = -EIO;
}
if (!list_empty(&pagelist))
putback_lru_pages(&pagelist);
up_write(&mm->mmap_sem);
mpol_free(new);
return err;
}
/* Set the process memory policy */
long do_set_mempolicy(int mode, nodemask_t *nodes)
{
struct mempolicy *new;
if (contextualize_policy(mode, nodes))
return -EINVAL;
new = mpol_new(mode, nodes);
if (IS_ERR(new))
return PTR_ERR(new);
mpol_free(current->mempolicy);
current->mempolicy = new;
if (new && new->policy == MPOL_INTERLEAVE)
current->il_next = first_node(new->v.nodes);
return 0;
}
/* Fill a zone bitmap for a policy */
static void get_zonemask(struct mempolicy *p, nodemask_t *nodes)
{
int i;
nodes_clear(*nodes);
switch (p->policy) {
case MPOL_BIND:
for (i = 0; p->v.zonelist->zones[i]; i++)
node_set(p->v.zonelist->zones[i]->zone_pgdat->node_id,
*nodes);
break;
case MPOL_DEFAULT:
break;
case MPOL_INTERLEAVE:
*nodes = p->v.nodes;
break;
case MPOL_PREFERRED:
/* or use current node instead of online map? */
if (p->v.preferred_node < 0)
*nodes = node_online_map;
else
node_set(p->v.preferred_node, *nodes);
break;
default:
BUG();
}
}
static int lookup_node(struct mm_struct *mm, unsigned long addr)
{
struct page *p;
int err;
err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL);
if (err >= 0) {
err = page_to_nid(p);
put_page(p);
}
return err;
}
/* Retrieve NUMA policy */
long do_get_mempolicy(int *policy, nodemask_t *nmask,
unsigned long addr, unsigned long flags)
{
int err;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma = NULL;
struct mempolicy *pol = current->mempolicy;
[PATCH] cpusets: automatic numa mempolicy rebinding This patch automatically updates a tasks NUMA mempolicy when its cpuset memory placement changes. It does so within the context of the task, without any need to support low level external mempolicy manipulation. If a system is not using cpusets, or if running on a system with just the root (all-encompassing) cpuset, then this remap is a no-op. Only when a task is moved between cpusets, or a cpusets memory placement is changed does the following apply. Otherwise, the main routine below, rebind_policy() is not even called. When mixing cpusets, scheduler affinity, and NUMA mempolicies, the essential role of cpusets is to place jobs (several related tasks) on a set of CPUs and Memory Nodes, the essential role of sched_setaffinity is to manage a jobs processor placement within its allowed cpuset, and the essential role of NUMA mempolicy (mbind, set_mempolicy) is to manage a jobs memory placement within its allowed cpuset. However, CPU affinity and NUMA memory placement are managed within the kernel using absolute system wide numbering, not cpuset relative numbering. This is ok until a job is migrated to a different cpuset, or what's the same, a jobs cpuset is moved to different CPUs and Memory Nodes. Then the CPU affinity and NUMA memory placement of the tasks in the job need to be updated, to preserve their cpuset-relative position. This can be done for CPU affinity using sched_setaffinity() from user code, as one task can modify anothers CPU affinity. This cannot be done from an external task for NUMA memory placement, as that can only be modified in the context of the task using it. However, it easy enough to remap a tasks NUMA mempolicy automatically when a task is migrated, using the existing cpuset mechanism to trigger a refresh of a tasks memory placement after its cpuset has changed. All that is needed is the old and new nodemask, and notice to the task that it needs to rebind its mempolicy. The tasks mems_allowed has the old mask, the tasks cpuset has the new mask, and the existing cpuset_update_current_mems_allowed() mechanism provides the notice. The bitmap/cpumask/nodemask remap operators provide the cpuset relative calculations. This patch leaves open a couple of issues: 1) Updating vma and shmfs/tmpfs/hugetlbfs memory policies: These mempolicies may reference nodes outside of those allowed to the current task by its cpuset. Tasks are migrated as part of jobs, which reside on what might be several cpusets in a subtree. When such a job is migrated, all NUMA memory policy references to nodes within that cpuset subtree should be translated, and references to any nodes outside that subtree should be left untouched. A future patch will provide the cpuset mechanism needed to mark such subtrees. With that patch, we will be able to correctly migrate these other memory policies across a job migration. 2) Updating cpuset, affinity and memory policies in user space: This is harder. Any placement state stored in user space using system-wide numbering will be invalidated across a migration. More work will be required to provide user code with a migration-safe means to manage its cpuset relative placement, while preserving the current API's that pass system wide numbers, not cpuset relative numbers across the kernel-user boundary. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 23:02:36 +00:00
cpuset_update_current_mems_allowed();
if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR))
return -EINVAL;
if (flags & MPOL_F_ADDR) {
down_read(&mm->mmap_sem);
vma = find_vma_intersection(mm, addr, addr+1);
if (!vma) {
up_read(&mm->mmap_sem);
return -EFAULT;
}
if (vma->vm_ops && vma->vm_ops->get_policy)
pol = vma->vm_ops->get_policy(vma, addr);
else
pol = vma->vm_policy;
} else if (addr)
return -EINVAL;
if (!pol)
pol = &default_policy;
if (flags & MPOL_F_NODE) {
if (flags & MPOL_F_ADDR) {
err = lookup_node(mm, addr);
if (err < 0)
goto out;
*policy = err;
} else if (pol == current->mempolicy &&
pol->policy == MPOL_INTERLEAVE) {
*policy = current->il_next;
} else {
err = -EINVAL;
goto out;
}
} else
*policy = pol->policy;
if (vma) {
up_read(&current->mm->mmap_sem);
vma = NULL;
}
err = 0;
if (nmask)
get_zonemask(pol, nmask);
out:
if (vma)
up_read(&current->mm->mmap_sem);
return err;
}
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
/*
* For now migrate_pages simply swaps out the pages from nodes that are in
* the source set but not in the target set. In the future, we would
* want a function that moves pages between the two nodesets in such
* a way 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 count = 0;
nodemask_t nodes;
nodes_andnot(nodes, *from_nodes, *to_nodes);
nodes_complement(nodes, nodes);
down_read(&mm->mmap_sem);
check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nodes,
flags | MPOL_MF_DISCONTIG_OK, &pagelist);
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
if (!list_empty(&pagelist)) {
count = swap_pages(&pagelist);
putback_lru_pages(&pagelist);
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
}
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
up_read(&mm->mmap_sem);
return count;
}
/*
* User space interface with variable sized bitmaps for nodelists.
*/
/* Copy a node mask from user space. */
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
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;
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);
}
[PATCH] Swap Migration V5: sys_migrate_pages interface sys_migrate_pages implementation using swap based page migration This is the original API proposed by Ray Bryant in his posts during the first half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org. The intent of sys_migrate is to migrate memory of a process. A process may have migrated to another node. Memory was allocated optimally for the prior context. sys_migrate_pages allows to shift the memory to the new node. sys_migrate_pages is also useful if the processes available memory nodes have changed through cpuset operations to manually move the processes memory. Paul Jackson is working on an automated mechanism that will allow an automatic migration if the cpuset of a process is changed. However, a user may decide to manually control the migration. This implementation is put into the policy layer since it uses concepts and functions that are also needed for mbind and friends. The patch also provides a do_migrate_pages function that may be useful for cpusets to automatically move memory. sys_migrate_pages does not modify policies in contrast to Ray's implementation. The current code here is based on the swap based page migration capability and thus is not able to preserve the physical layout relative to it containing nodeset (which may be a cpuset). When direct page migration becomes available then the implementation needs to be changed to do a isomorphic move of pages between different nodesets. The current implementation simply evicts all pages in source nodeset that are not in the target nodeset. Patch supports ia64, i386 and x86_64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 09:00:51 +00:00
/* Macro needed until Paul implements this function in kernel/cpusets.c */
#define cpuset_mems_allowed(task) node_online_map
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 priviledges 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_ADMIN)) {
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_ADMIN)) {
err = -EPERM;
goto out;
}
err = do_migrate_pages(mm, &old, &new, 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
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(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 */
[PATCH] /proc/<pid>/numa_maps to show on which nodes pages reside This patch was recently discussed on linux-mm: http://marc.theaimsgroup.com/?t=112085728500002&r=1&w=2 I inherited a large code base from Ray for page migration. There was a small patch in there that I find to be very useful since it allows the display of the locality of the pages in use by a process. I reworked that patch and came up with a /proc/<pid>/numa_maps that gives more information about the vma's of a process. numa_maps is indexes by the start address found in /proc/<pid>/maps. F.e. with this patch you can see the page use of the "getty" process: margin:/proc/12008 # cat maps 00000000-00004000 r--p 00000000 00:00 0 2000000000000000-200000000002c000 r-xp 00000000 08:04 516 /lib/ld-2.3.3.so 2000000000038000-2000000000040000 rw-p 00028000 08:04 516 /lib/ld-2.3.3.so 2000000000040000-2000000000044000 rw-p 2000000000040000 00:00 0 2000000000058000-2000000000260000 r-xp 00000000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000260000-2000000000268000 ---p 00208000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000268000-2000000000274000 rw-p 00200000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000274000-2000000000280000 rw-p 2000000000274000 00:00 0 2000000000280000-20000000002b4000 r--p 00000000 08:04 9126923 /usr/lib/locale/en_US.utf8/LC_CTYPE 2000000000300000-2000000000308000 r--s 00000000 08:04 60071467 /usr/lib/gconv/gconv-modules.cache 2000000000318000-2000000000328000 rw-p 2000000000318000 00:00 0 4000000000000000-4000000000008000 r-xp 00000000 08:04 29576399 /sbin/mingetty 6000000000004000-6000000000008000 rw-p 00004000 08:04 29576399 /sbin/mingetty 6000000000008000-600000000002c000 rw-p 6000000000008000 00:00 0 [heap] 60000fff7fffc000-60000fff80000000 rw-p 60000fff7fffc000 00:00 0 60000ffffff44000-60000ffffff98000 rw-p 60000ffffff44000 00:00 0 [stack] a000000000000000-a000000000020000 ---p 00000000 00:00 0 [vdso] cat numa_maps 2000000000000000 default MaxRef=43 Pages=11 Mapped=11 N0=4 N1=3 N2=2 N3=2 2000000000038000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000040000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 2000000000058000 default MaxRef=43 Pages=61 Mapped=61 N0=14 N1=15 N2=16 N3=16 2000000000268000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000274000 default MaxRef=1 Pages=3 Mapped=3 Anon=3 N0=3 2000000000280000 default MaxRef=8 Pages=3 Mapped=3 N0=3 2000000000300000 default MaxRef=8 Pages=2 Mapped=2 N0=2 2000000000318000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N2=1 4000000000000000 default MaxRef=6 Pages=2 Mapped=2 N1=2 6000000000004000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 6000000000008000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000fff7fffc000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000ffffff44000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 getty uses ld.so. The first vma is the code segment which is used by 43 other processes and the pages are evenly distributed over the 4 nodes. The second vma is the process specific data portion for ld.so. This is only one page. The display format is: <startaddress> Links to information in /proc/<pid>/map <memory policy> This can be "default" "interleave={}", "prefer=<node>" or "bind={<zones>}" MaxRef= <maximum reference to a page in this vma> Pages= <Nr of pages in use> Mapped= <Nr of pages with mapcount > Anon= <nr of anonymous pages> Nx= <Nr of pages on Node x> The content of the proc-file is self-evident. If this would be tied into the sparsemem system then the contents of this file would not be too useful. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-03 22:54:45 +00:00
struct mempolicy *
get_vma_policy(struct task_struct *task, struct vm_area_struct *vma, unsigned long addr)
{
[PATCH] /proc/<pid>/numa_maps to show on which nodes pages reside This patch was recently discussed on linux-mm: http://marc.theaimsgroup.com/?t=112085728500002&r=1&w=2 I inherited a large code base from Ray for page migration. There was a small patch in there that I find to be very useful since it allows the display of the locality of the pages in use by a process. I reworked that patch and came up with a /proc/<pid>/numa_maps that gives more information about the vma's of a process. numa_maps is indexes by the start address found in /proc/<pid>/maps. F.e. with this patch you can see the page use of the "getty" process: margin:/proc/12008 # cat maps 00000000-00004000 r--p 00000000 00:00 0 2000000000000000-200000000002c000 r-xp 00000000 08:04 516 /lib/ld-2.3.3.so 2000000000038000-2000000000040000 rw-p 00028000 08:04 516 /lib/ld-2.3.3.so 2000000000040000-2000000000044000 rw-p 2000000000040000 00:00 0 2000000000058000-2000000000260000 r-xp 00000000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000260000-2000000000268000 ---p 00208000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000268000-2000000000274000 rw-p 00200000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000274000-2000000000280000 rw-p 2000000000274000 00:00 0 2000000000280000-20000000002b4000 r--p 00000000 08:04 9126923 /usr/lib/locale/en_US.utf8/LC_CTYPE 2000000000300000-2000000000308000 r--s 00000000 08:04 60071467 /usr/lib/gconv/gconv-modules.cache 2000000000318000-2000000000328000 rw-p 2000000000318000 00:00 0 4000000000000000-4000000000008000 r-xp 00000000 08:04 29576399 /sbin/mingetty 6000000000004000-6000000000008000 rw-p 00004000 08:04 29576399 /sbin/mingetty 6000000000008000-600000000002c000 rw-p 6000000000008000 00:00 0 [heap] 60000fff7fffc000-60000fff80000000 rw-p 60000fff7fffc000 00:00 0 60000ffffff44000-60000ffffff98000 rw-p 60000ffffff44000 00:00 0 [stack] a000000000000000-a000000000020000 ---p 00000000 00:00 0 [vdso] cat numa_maps 2000000000000000 default MaxRef=43 Pages=11 Mapped=11 N0=4 N1=3 N2=2 N3=2 2000000000038000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000040000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 2000000000058000 default MaxRef=43 Pages=61 Mapped=61 N0=14 N1=15 N2=16 N3=16 2000000000268000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000274000 default MaxRef=1 Pages=3 Mapped=3 Anon=3 N0=3 2000000000280000 default MaxRef=8 Pages=3 Mapped=3 N0=3 2000000000300000 default MaxRef=8 Pages=2 Mapped=2 N0=2 2000000000318000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N2=1 4000000000000000 default MaxRef=6 Pages=2 Mapped=2 N1=2 6000000000004000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 6000000000008000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000fff7fffc000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000ffffff44000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 getty uses ld.so. The first vma is the code segment which is used by 43 other processes and the pages are evenly distributed over the 4 nodes. The second vma is the process specific data portion for ld.so. This is only one page. The display format is: <startaddress> Links to information in /proc/<pid>/map <memory policy> This can be "default" "interleave={}", "prefer=<node>" or "bind={<zones>}" MaxRef= <maximum reference to a page in this vma> Pages= <Nr of pages in use> Mapped= <Nr of pages with mapcount > Anon= <nr of anonymous pages> Nx= <Nr of pages on Node x> The content of the proc-file is self-evident. If this would be tied into the sparsemem system then the contents of this file would not be too useful. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-03 22:54:45 +00:00
struct mempolicy *pol = task->mempolicy;
if (vma) {
if (vma->vm_ops && vma->vm_ops->get_policy)
pol = vma->vm_ops->get_policy(vma, addr);
else if (vma->vm_policy &&
vma->vm_policy->policy != MPOL_DEFAULT)
pol = vma->vm_policy;
}
if (!pol)
pol = &default_policy;
return pol;
}
/* Return a zonelist representing a mempolicy */
static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy)
{
int nd;
switch (policy->policy) {
case MPOL_PREFERRED:
nd = policy->v.preferred_node;
if (nd < 0)
nd = numa_node_id();
break;
case MPOL_BIND:
/* Lower zones don't get a policy applied */
/* 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 = numa_node_id();
break;
default:
nd = 0;
BUG();
}
return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp);
}
/* Do dynamic interleaving for a process */
static unsigned interleave_nodes(struct mempolicy *policy)
{
unsigned nid, next;
struct task_struct *me = current;
nid = me->il_next;
next = next_node(nid, policy->v.nodes);
if (next >= MAX_NUMNODES)
next = first_node(policy->v.nodes);
me->il_next = next;
return nid;
}
/* 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 = nodes_weight(pol->v.nodes);
unsigned target = (unsigned)off % nnodes;
int c;
int nid = -1;
c = 0;
do {
nid = next_node(nid, pol->v.nodes);
c++;
} while (c <= target);
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;
off = vma->vm_pgoff;
off += (addr - vma->vm_start) >> shift;
return offset_il_node(pol, vma, off);
} else
return interleave_nodes(pol);
}
/* 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);
}
/* Allocate a page in interleaved policy.
Own path because it needs to do special accounting. */
static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
unsigned nid)
{
struct zonelist *zl;
struct page *page;
zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
page = __alloc_pages(gfp, order, zl);
if (page && page_zone(page) == zl->zones[0]) {
[PATCH] node local per-cpu-pages This patch modifies the way pagesets in struct zone are managed. Each zone has a per-cpu array of pagesets. So any particular CPU has some memory in each zone structure which belongs to itself. Even if that CPU is not local to that zone. So the patch relocates the pagesets for each cpu to the node that is nearest to the cpu instead of allocating the pagesets in the (possibly remote) target zone. This means that the operations to manage pages on remote zone can be done with information available locally. We play a macro trick so that non-NUMA pmachines avoid the additional pointer chase on the page allocator fastpath. AIM7 benchmark on a 32 CPU SGI Altix w/o patches: Tasks jobs/min jti jobs/min/task real cpu 1 484.68 100 484.6769 12.01 1.97 Fri Mar 25 11:01:42 2005 100 27140.46 89 271.4046 21.44 148.71 Fri Mar 25 11:02:04 2005 200 30792.02 82 153.9601 37.80 296.72 Fri Mar 25 11:02:42 2005 300 32209.27 81 107.3642 54.21 451.34 Fri Mar 25 11:03:37 2005 400 34962.83 78 87.4071 66.59 588.97 Fri Mar 25 11:04:44 2005 500 31676.92 75 63.3538 91.87 742.71 Fri Mar 25 11:06:16 2005 600 36032.69 73 60.0545 96.91 885.44 Fri Mar 25 11:07:54 2005 700 35540.43 77 50.7720 114.63 1024.28 Fri Mar 25 11:09:49 2005 800 33906.70 74 42.3834 137.32 1181.65 Fri Mar 25 11:12:06 2005 900 34120.67 73 37.9119 153.51 1325.26 Fri Mar 25 11:14:41 2005 1000 34802.37 74 34.8024 167.23 1465.26 Fri Mar 25 11:17:28 2005 with slab API changes and pageset patch: Tasks jobs/min jti jobs/min/task real cpu 1 485.00 100 485.0000 12.00 1.96 Fri Mar 25 11:46:18 2005 100 28000.96 89 280.0096 20.79 150.45 Fri Mar 25 11:46:39 2005 200 32285.80 79 161.4290 36.05 293.37 Fri Mar 25 11:47:16 2005 300 40424.15 84 134.7472 43.19 438.42 Fri Mar 25 11:47:59 2005 400 39155.01 79 97.8875 59.46 590.05 Fri Mar 25 11:48:59 2005 500 37881.25 82 75.7625 76.82 730.19 Fri Mar 25 11:50:16 2005 600 39083.14 78 65.1386 89.35 872.79 Fri Mar 25 11:51:46 2005 700 38627.83 77 55.1826 105.47 1022.46 Fri Mar 25 11:53:32 2005 800 39631.94 78 49.5399 117.48 1169.94 Fri Mar 25 11:55:30 2005 900 36903.70 79 41.0041 141.94 1310.78 Fri Mar 25 11:57:53 2005 1000 36201.23 77 36.2012 160.77 1458.31 Fri Mar 25 12:00:34 2005 Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com> Signed-off-by: Shai Fultheim <Shai@Scalex86.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-22 00:14:47 +00:00
zone_pcp(zl->zones[0],get_cpu())->interleave_hit++;
put_cpu();
}
return page;
}
/**
* alloc_page_vma - Allocate a page for a VMA.
*
* @gfp:
* %GFP_USER user allocation.
* %GFP_KERNEL kernel allocations,
* %GFP_HIGHMEM highmem/user allocations,
* %GFP_FS allocation should not call back into a file system.
* %GFP_ATOMIC don't sleep.
*
* @vma: Pointer to VMA or NULL if not available.
* @addr: Virtual Address of the allocation. Must be inside the VMA.
*
* This function allocates a page from the kernel page pool and applies
* a NUMA policy associated with the VMA or the current process.
* When VMA is not NULL caller must hold down_read on the mmap_sem of the
* mm_struct of the VMA to prevent it from going away. Should be used for
* all allocations for pages that will be mapped into
* user space. Returns NULL when no page can be allocated.
*
* Should be called with the mm_sem of the vma hold.
*/
struct page *
alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
{
[PATCH] /proc/<pid>/numa_maps to show on which nodes pages reside This patch was recently discussed on linux-mm: http://marc.theaimsgroup.com/?t=112085728500002&r=1&w=2 I inherited a large code base from Ray for page migration. There was a small patch in there that I find to be very useful since it allows the display of the locality of the pages in use by a process. I reworked that patch and came up with a /proc/<pid>/numa_maps that gives more information about the vma's of a process. numa_maps is indexes by the start address found in /proc/<pid>/maps. F.e. with this patch you can see the page use of the "getty" process: margin:/proc/12008 # cat maps 00000000-00004000 r--p 00000000 00:00 0 2000000000000000-200000000002c000 r-xp 00000000 08:04 516 /lib/ld-2.3.3.so 2000000000038000-2000000000040000 rw-p 00028000 08:04 516 /lib/ld-2.3.3.so 2000000000040000-2000000000044000 rw-p 2000000000040000 00:00 0 2000000000058000-2000000000260000 r-xp 00000000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000260000-2000000000268000 ---p 00208000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000268000-2000000000274000 rw-p 00200000 08:04 54707842 /lib/tls/libc.so.6.1 2000000000274000-2000000000280000 rw-p 2000000000274000 00:00 0 2000000000280000-20000000002b4000 r--p 00000000 08:04 9126923 /usr/lib/locale/en_US.utf8/LC_CTYPE 2000000000300000-2000000000308000 r--s 00000000 08:04 60071467 /usr/lib/gconv/gconv-modules.cache 2000000000318000-2000000000328000 rw-p 2000000000318000 00:00 0 4000000000000000-4000000000008000 r-xp 00000000 08:04 29576399 /sbin/mingetty 6000000000004000-6000000000008000 rw-p 00004000 08:04 29576399 /sbin/mingetty 6000000000008000-600000000002c000 rw-p 6000000000008000 00:00 0 [heap] 60000fff7fffc000-60000fff80000000 rw-p 60000fff7fffc000 00:00 0 60000ffffff44000-60000ffffff98000 rw-p 60000ffffff44000 00:00 0 [stack] a000000000000000-a000000000020000 ---p 00000000 00:00 0 [vdso] cat numa_maps 2000000000000000 default MaxRef=43 Pages=11 Mapped=11 N0=4 N1=3 N2=2 N3=2 2000000000038000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000040000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 2000000000058000 default MaxRef=43 Pages=61 Mapped=61 N0=14 N1=15 N2=16 N3=16 2000000000268000 default MaxRef=1 Pages=2 Mapped=2 Anon=2 N0=2 2000000000274000 default MaxRef=1 Pages=3 Mapped=3 Anon=3 N0=3 2000000000280000 default MaxRef=8 Pages=3 Mapped=3 N0=3 2000000000300000 default MaxRef=8 Pages=2 Mapped=2 N0=2 2000000000318000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N2=1 4000000000000000 default MaxRef=6 Pages=2 Mapped=2 N1=2 6000000000004000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 6000000000008000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000fff7fffc000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 60000ffffff44000 default MaxRef=1 Pages=1 Mapped=1 Anon=1 N0=1 getty uses ld.so. The first vma is the code segment which is used by 43 other processes and the pages are evenly distributed over the 4 nodes. The second vma is the process specific data portion for ld.so. This is only one page. The display format is: <startaddress> Links to information in /proc/<pid>/map <memory policy> This can be "default" "interleave={}", "prefer=<node>" or "bind={<zones>}" MaxRef= <maximum reference to a page in this vma> Pages= <Nr of pages in use> Mapped= <Nr of pages with mapcount > Anon= <nr of anonymous pages> Nx= <Nr of pages on Node x> The content of the proc-file is self-evident. If this would be tied into the sparsemem system then the contents of this file would not be too useful. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-03 22:54:45 +00:00
struct mempolicy *pol = get_vma_policy(current, vma, addr);
cpuset_update_current_mems_allowed();
if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
unsigned nid;
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
return alloc_page_interleave(gfp, 0, nid);
}
return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol));
}
/**
* alloc_pages_current - Allocate pages.
*
* @gfp:
* %GFP_USER user allocation,
* %GFP_KERNEL kernel allocation,
* %GFP_HIGHMEM highmem allocation,
* %GFP_FS don't call back into a file system.
* %GFP_ATOMIC don't sleep.
* @order: Power of two of allocation size in pages. 0 is a single page.
*
* 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_current_mems_allowed() unless
* 1) it's ok to take cpuset_sem (can WAIT), and
* 2) allocating for current task (not interrupt).
*/
struct page *alloc_pages_current(gfp_t gfp, unsigned order)
{
struct mempolicy *pol = current->mempolicy;
if ((gfp & __GFP_WAIT) && !in_interrupt())
cpuset_update_current_mems_allowed();
if (!pol || in_interrupt())
pol = &default_policy;
if (pol->policy == MPOL_INTERLEAVE)
return alloc_page_interleave(gfp, order, interleave_nodes(pol));
return __alloc_pages(gfp, order, zonelist_policy(gfp, pol));
}
EXPORT_SYMBOL(alloc_pages_current);
/* Slow path of a mempolicy copy */
struct mempolicy *__mpol_copy(struct mempolicy *old)
{
struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
if (!new)
return ERR_PTR(-ENOMEM);
*new = *old;
atomic_set(&new->refcnt, 1);
if (new->policy == MPOL_BIND) {
int sz = ksize(old->v.zonelist);
new->v.zonelist = kmalloc(sz, SLAB_KERNEL);
if (!new->v.zonelist) {
kmem_cache_free(policy_cache, new);
return ERR_PTR(-ENOMEM);
}
memcpy(new->v.zonelist, old->v.zonelist, sz);
}
return new;
}
/* Slow path of a mempolicy comparison */
int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
{
if (!a || !b)
return 0;
if (a->policy != b->policy)
return 0;
switch (a->policy) {
case MPOL_DEFAULT:
return 1;
case MPOL_INTERLEAVE:
return nodes_equal(a->v.nodes, b->v.nodes);
case MPOL_PREFERRED:
return a->v.preferred_node == b->v.preferred_node;
case MPOL_BIND: {
int i;
for (i = 0; a->v.zonelist->zones[i]; i++)
if (a->v.zonelist->zones[i] != b->v.zonelist->zones[i])
return 0;
return b->v.zonelist->zones[i] == NULL;
}
default:
BUG();
return 0;
}
}
/* Slow path of a mpol destructor. */
void __mpol_free(struct mempolicy *p)
{
if (!atomic_dec_and_test(&p->refcnt))
return;
if (p->policy == MPOL_BIND)
kfree(p->v.zonelist);
p->policy = MPOL_DEFAULT;
kmem_cache_free(policy_cache, p);
}
/*
* 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->lock spinlock, which should be held
* for any accesses to the tree.
*/
/* lookup first element intersecting start-end */
/* Caller holds sp->lock */
static struct sp_node *
sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
{
struct rb_node *n = sp->root.rb_node;
while (n) {
struct sp_node *p = rb_entry(n, struct sp_node, nd);
if (start >= p->end)
n = n->rb_right;
else if (end <= p->start)
n = n->rb_left;
else
break;
}
if (!n)
return NULL;
for (;;) {
struct sp_node *w = NULL;
struct rb_node *prev = rb_prev(n);
if (!prev)
break;
w = rb_entry(prev, struct sp_node, nd);
if (w->end <= start)
break;
n = prev;
}
return rb_entry(n, struct sp_node, nd);
}
/* Insert a new shared policy into the list. */
/* 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 rb_node *parent = NULL;
struct sp_node *nd;
while (*p) {
parent = *p;
nd = rb_entry(parent, struct sp_node, nd);
if (new->start < nd->start)
p = &(*p)->rb_left;
else if (new->end > nd->end)
p = &(*p)->rb_right;
else
BUG();
}
rb_link_node(&new->nd, parent, p);
rb_insert_color(&new->nd, &sp->root);
PDprintk("inserting %lx-%lx: %d\n", new->start, new->end,
new->policy ? new->policy->policy : 0);
}
/* Find shared policy intersecting idx */
struct mempolicy *
mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
{
struct mempolicy *pol = NULL;
struct sp_node *sn;
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;
}
spin_unlock(&sp->lock);
return pol;
}
static void sp_delete(struct shared_policy *sp, struct sp_node *n)
{
PDprintk("deleting %lx-l%x\n", n->start, n->end);
rb_erase(&n->nd, &sp->root);
mpol_free(n->policy);
kmem_cache_free(sn_cache, n);
}
struct sp_node *
sp_alloc(unsigned long start, unsigned long end, struct mempolicy *pol)
{
struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL);
if (!n)
return NULL;
n->start = start;
n->end = end;
mpol_get(pol);
n->policy = pol;
return n;
}
/* Replace a policy range. */
static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
unsigned long end, struct sp_node *new)
{
struct sp_node *n, *new2 = NULL;
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) {
struct rb_node *next = rb_next(&n->nd);
if (n->start >= start) {
if (n->end <= end)
sp_delete(sp, n);
else
n->start = end;
} else {
/* Old policy spanning whole new range. */
if (n->end > end) {
if (!new2) {
spin_unlock(&sp->lock);
new2 = sp_alloc(end, n->end, n->policy);
if (!new2)
return -ENOMEM;
goto restart;
}
n->end = start;
sp_insert(sp, new2);
new2 = NULL;
break;
} else
n->end = start;
}
if (!next)
break;
n = rb_entry(next, struct sp_node, nd);
}
if (new)
sp_insert(sp, new);
spin_unlock(&sp->lock);
if (new2) {
mpol_free(new2->policy);
kmem_cache_free(sn_cache, new2);
}
return 0;
}
int mpol_set_shared_policy(struct shared_policy *info,
struct vm_area_struct *vma, struct mempolicy *npol)
{
int err;
struct sp_node *new = NULL;
unsigned long sz = vma_pages(vma);
PDprintk("set_shared_policy %lx sz %lu %d %lx\n",
vma->vm_pgoff,
sz, npol? npol->policy : -1,
npol ? nodes_addr(npol->v.nodes)[0] : -1);
if (npol) {
new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
if (!new)
return -ENOMEM;
}
err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
if (err && new)
kmem_cache_free(sn_cache, new);
return err;
}
/* Free a backing policy store on inode delete. */
void mpol_free_shared_policy(struct shared_policy *p)
{
struct sp_node *n;
struct rb_node *next;
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);
next = rb_next(&n->nd);
rb_erase(&n->nd, &p->root);
mpol_free(n->policy);
kmem_cache_free(sn_cache, n);
}
spin_unlock(&p->lock);
}
/* assumes fs == KERNEL_DS */
void __init numa_policy_init(void)
{
policy_cache = kmem_cache_create("numa_policy",
sizeof(struct mempolicy),
0, SLAB_PANIC, NULL, NULL);
sn_cache = kmem_cache_create("shared_policy_node",
sizeof(struct sp_node),
0, SLAB_PANIC, NULL, NULL);
/* Set interleaving policy for system init. This way not all
the data structures allocated at system boot end up in node zero. */
if (do_set_mempolicy(MPOL_INTERLEAVE, &node_online_map))
printk("numa_policy_init: interleaving failed\n");
}
/* Reset policy of current process to default */
void numa_default_policy(void)
{
do_set_mempolicy(MPOL_DEFAULT, NULL);
}
[PATCH] cpusets: automatic numa mempolicy rebinding This patch automatically updates a tasks NUMA mempolicy when its cpuset memory placement changes. It does so within the context of the task, without any need to support low level external mempolicy manipulation. If a system is not using cpusets, or if running on a system with just the root (all-encompassing) cpuset, then this remap is a no-op. Only when a task is moved between cpusets, or a cpusets memory placement is changed does the following apply. Otherwise, the main routine below, rebind_policy() is not even called. When mixing cpusets, scheduler affinity, and NUMA mempolicies, the essential role of cpusets is to place jobs (several related tasks) on a set of CPUs and Memory Nodes, the essential role of sched_setaffinity is to manage a jobs processor placement within its allowed cpuset, and the essential role of NUMA mempolicy (mbind, set_mempolicy) is to manage a jobs memory placement within its allowed cpuset. However, CPU affinity and NUMA memory placement are managed within the kernel using absolute system wide numbering, not cpuset relative numbering. This is ok until a job is migrated to a different cpuset, or what's the same, a jobs cpuset is moved to different CPUs and Memory Nodes. Then the CPU affinity and NUMA memory placement of the tasks in the job need to be updated, to preserve their cpuset-relative position. This can be done for CPU affinity using sched_setaffinity() from user code, as one task can modify anothers CPU affinity. This cannot be done from an external task for NUMA memory placement, as that can only be modified in the context of the task using it. However, it easy enough to remap a tasks NUMA mempolicy automatically when a task is migrated, using the existing cpuset mechanism to trigger a refresh of a tasks memory placement after its cpuset has changed. All that is needed is the old and new nodemask, and notice to the task that it needs to rebind its mempolicy. The tasks mems_allowed has the old mask, the tasks cpuset has the new mask, and the existing cpuset_update_current_mems_allowed() mechanism provides the notice. The bitmap/cpumask/nodemask remap operators provide the cpuset relative calculations. This patch leaves open a couple of issues: 1) Updating vma and shmfs/tmpfs/hugetlbfs memory policies: These mempolicies may reference nodes outside of those allowed to the current task by its cpuset. Tasks are migrated as part of jobs, which reside on what might be several cpusets in a subtree. When such a job is migrated, all NUMA memory policy references to nodes within that cpuset subtree should be translated, and references to any nodes outside that subtree should be left untouched. A future patch will provide the cpuset mechanism needed to mark such subtrees. With that patch, we will be able to correctly migrate these other memory policies across a job migration. 2) Updating cpuset, affinity and memory policies in user space: This is harder. Any placement state stored in user space using system-wide numbering will be invalidated across a migration. More work will be required to provide user code with a migration-safe means to manage its cpuset relative placement, while preserving the current API's that pass system wide numbers, not cpuset relative numbers across the kernel-user boundary. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 23:02:36 +00:00
/* Migrate a policy to a different set of nodes */
static void rebind_policy(struct mempolicy *pol, const nodemask_t *old,
const nodemask_t *new)
{
nodemask_t tmp;
if (!pol)
return;
switch (pol->policy) {
case MPOL_DEFAULT:
break;
case MPOL_INTERLEAVE:
nodes_remap(tmp, pol->v.nodes, *old, *new);
pol->v.nodes = tmp;
current->il_next = node_remap(current->il_next, *old, *new);
break;
case MPOL_PREFERRED:
pol->v.preferred_node = node_remap(pol->v.preferred_node,
*old, *new);
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, *old, *new);
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;
}
break;
}
default:
BUG();
break;
}
}
/*
* Someone moved this task to different nodes. Fixup mempolicies.
*
* TODO - fixup current->mm->vma and shmfs/tmpfs/hugetlbfs policies as well,
* once we have a cpuset mechanism to mark which cpuset subtree is migrating.
*/
void numa_policy_rebind(const nodemask_t *old, const nodemask_t *new)
{
rebind_policy(current->mempolicy, old, new);
}