mempolicy: alloc_pages_mpol() for NUMA policy without vma

Shrink shmem's stack usage by eliminating the pseudo-vma from its folio
allocation.  alloc_pages_mpol(gfp, order, pol, ilx, nid) becomes the
principal actor for passing mempolicy choice down to __alloc_pages(),
rather than vma_alloc_folio(gfp, order, vma, addr, hugepage).

vma_alloc_folio() and alloc_pages() remain, but as wrappers around
alloc_pages_mpol().  alloc_pages_bulk_*() untouched, except to provide the
additional args to policy_nodemask(), which subsumes policy_node(). 
Cleanup throughout, cutting out some unhelpful "helpers".

It would all be much simpler without MPOL_INTERLEAVE, but that adds a
dynamic to the constant mpol: complicated by v3.6 commit 09c231cb8b
("tmpfs: distribute interleave better across nodes"), which added ino bias
to the interleave, hidden from mm/mempolicy.c until this commit.

Hence "ilx" throughout, the "interleave index".  Originally I thought it
could be done just with nid, but that's wrong: the nodemask may come from
the shared policy layer below a shmem vma, or it may come from the task
layer above a shmem vma; and without the final nodemask then nodeid cannot
be decided.  And how ilx is applied depends also on page order.

The interleave index is almost always irrelevant unless MPOL_INTERLEAVE:
with one exception in alloc_pages_mpol(), where the NO_INTERLEAVE_INDEX
passed down from vma-less alloc_pages() is also used as hint not to use
THP-style hugepage allocation - to avoid the overhead of a hugepage arg
(though I don't understand why we never just added a GFP bit for THP - if
it actually needs a different allocation strategy from other pages of the
same order).  vma_alloc_folio() still carries its hugepage arg here, but
it is not used, and should be removed when agreed.

get_vma_policy() no longer allows a NULL vma: over time I believe we've
eradicated all the places which used to need it e.g.  swapoff and madvise
used to pass NULL vma to read_swap_cache_async(), but now know the vma.

[hughd@google.com: handle NULL mpol being passed to __read_swap_cache_async()]
  Link: https://lkml.kernel.org/r/ea419956-4751-0102-21f7-9c93cb957892@google.com
Link: https://lkml.kernel.org/r/74e34633-6060-f5e3-aee-7040d43f2e93@google.com
Link: https://lkml.kernel.org/r/1738368e-bac0-fd11-ed7f-b87142a939fe@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun heo <tj@kernel.org>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Domenico Cerasuolo <mimmocerasuolo@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2023-10-19 13:39:08 -07:00 committed by Andrew Morton
parent 23e4883248
commit ddc1a5cbc0
10 changed files with 309 additions and 324 deletions

View File

@ -2673,8 +2673,9 @@ static int show_numa_map(struct seq_file *m, void *v)
struct numa_maps *md = &numa_priv->md;
struct file *file = vma->vm_file;
struct mm_struct *mm = vma->vm_mm;
struct mempolicy *pol;
char buffer[64];
struct mempolicy *pol;
pgoff_t ilx;
int nid;
if (!mm)
@ -2683,7 +2684,7 @@ static int show_numa_map(struct seq_file *m, void *v)
/* Ensure we start with an empty set of numa_maps statistics. */
memset(md, 0, sizeof(*md));
pol = __get_vma_policy(vma, vma->vm_start);
pol = __get_vma_policy(vma, vma->vm_start, &ilx);
if (pol) {
mpol_to_str(buffer, sizeof(buffer), pol);
mpol_cond_put(pol);

View File

@ -8,6 +8,7 @@
#include <linux/topology.h>
struct vm_area_struct;
struct mempolicy;
/* Convert GFP flags to their corresponding migrate type */
#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
@ -262,7 +263,9 @@ static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
#ifdef CONFIG_NUMA
struct page *alloc_pages(gfp_t gfp, unsigned int order);
struct folio *folio_alloc(gfp_t gfp, unsigned order);
struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order,
struct mempolicy *mpol, pgoff_t ilx, int nid);
struct folio *folio_alloc(gfp_t gfp, unsigned int order);
struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
unsigned long addr, bool hugepage);
#else
@ -270,6 +273,11 @@ static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
{
return alloc_pages_node(numa_node_id(), gfp_mask, order);
}
static inline struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order,
struct mempolicy *mpol, pgoff_t ilx, int nid)
{
return alloc_pages(gfp, order);
}
static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order)
{
return __folio_alloc_node(gfp, order, numa_node_id());

View File

@ -17,6 +17,8 @@
struct mm_struct;
#define NO_INTERLEAVE_INDEX (-1UL) /* use task il_prev for interleaving */
#ifdef CONFIG_NUMA
/*
@ -126,7 +128,9 @@ struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
struct mempolicy *get_task_policy(struct task_struct *p);
struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
unsigned long addr);
unsigned long addr, pgoff_t *ilx);
struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
unsigned long addr, int order, pgoff_t *ilx);
bool vma_policy_mof(struct vm_area_struct *vma);
extern void numa_default_policy(void);
@ -140,8 +144,6 @@ extern int huge_node(struct vm_area_struct *vma,
extern bool init_nodemask_of_mempolicy(nodemask_t *mask);
extern bool mempolicy_in_oom_domain(struct task_struct *tsk,
const nodemask_t *mask);
extern nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy);
extern unsigned int mempolicy_slab_node(void);
extern enum zone_type policy_zone;
@ -179,6 +181,11 @@ extern bool apply_policy_zone(struct mempolicy *policy, enum zone_type zone);
struct mempolicy {};
static inline struct mempolicy *get_task_policy(struct task_struct *p)
{
return NULL;
}
static inline bool mpol_equal(struct mempolicy *a, struct mempolicy *b)
{
return true;
@ -213,6 +220,13 @@ mpol_shared_policy_lookup(struct shared_policy *sp, pgoff_t idx)
return NULL;
}
static inline struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
unsigned long addr, int order, pgoff_t *ilx)
{
*ilx = 0;
return NULL;
}
static inline int
vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
{

View File

@ -619,7 +619,7 @@ struct vm_operations_struct {
* policy.
*/
struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
unsigned long addr);
unsigned long addr, pgoff_t *ilx);
#endif
/*
* Called by vm_normal_page() for special PTEs to find the

View File

@ -562,30 +562,25 @@ static unsigned long shm_pagesize(struct vm_area_struct *vma)
}
#ifdef CONFIG_NUMA
static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *mpol)
{
struct file *file = vma->vm_file;
struct shm_file_data *sfd = shm_file_data(file);
struct shm_file_data *sfd = shm_file_data(vma->vm_file);
int err = 0;
if (sfd->vm_ops->set_policy)
err = sfd->vm_ops->set_policy(vma, new);
err = sfd->vm_ops->set_policy(vma, mpol);
return err;
}
static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
unsigned long addr)
unsigned long addr, pgoff_t *ilx)
{
struct file *file = vma->vm_file;
struct shm_file_data *sfd = shm_file_data(file);
struct mempolicy *pol = NULL;
struct shm_file_data *sfd = shm_file_data(vma->vm_file);
struct mempolicy *mpol = vma->vm_policy;
if (sfd->vm_ops->get_policy)
pol = sfd->vm_ops->get_policy(vma, addr);
else if (vma->vm_policy)
pol = vma->vm_policy;
return pol;
mpol = sfd->vm_ops->get_policy(vma, addr, ilx);
return mpol;
}
#endif

View File

@ -898,6 +898,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
}
if (flags & MPOL_F_ADDR) {
pgoff_t ilx; /* ignored here */
/*
* Do NOT fall back to task policy if the
* vma/shared policy at addr is NULL. We
@ -909,10 +910,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
mmap_read_unlock(mm);
return -EFAULT;
}
if (vma->vm_ops && vma->vm_ops->get_policy)
pol = vma->vm_ops->get_policy(vma, addr);
else
pol = vma->vm_policy;
pol = __get_vma_policy(vma, addr, &ilx);
} else if (addr)
return -EINVAL;
@ -1170,6 +1168,15 @@ static struct folio *new_folio(struct folio *src, unsigned long start)
break;
}
/*
* __get_vma_policy() now expects a genuine non-NULL vma. Return NULL
* when the page can no longer be located in a vma: that is not ideal
* (migrate_pages() will give up early, presuming ENOMEM), but good
* enough to avoid a crash by syzkaller or concurrent holepunch.
*/
if (!vma)
return NULL;
if (folio_test_hugetlb(src)) {
return alloc_hugetlb_folio_vma(folio_hstate(src),
vma, address);
@ -1178,9 +1185,6 @@ static struct folio *new_folio(struct folio *src, unsigned long start)
if (folio_test_large(src))
gfp = GFP_TRANSHUGE;
/*
* if !vma, vma_alloc_folio() will use task or system default policy
*/
return vma_alloc_folio(gfp, folio_order(src), vma, address,
folio_test_large(src));
}
@ -1690,34 +1694,19 @@ bool vma_migratable(struct vm_area_struct *vma)
}
struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
unsigned long addr)
unsigned long addr, pgoff_t *ilx)
{
struct mempolicy *pol = NULL;
if (vma) {
if (vma->vm_ops && vma->vm_ops->get_policy) {
pol = vma->vm_ops->get_policy(vma, addr);
} else if (vma->vm_policy) {
pol = vma->vm_policy;
/*
* shmem_alloc_page() passes MPOL_F_SHARED policy with
* a pseudo vma whose vma->vm_ops=NULL. Take a reference
* count on these policies which will be dropped by
* mpol_cond_put() later
*/
if (mpol_needs_cond_ref(pol))
mpol_get(pol);
}
}
return pol;
*ilx = 0;
return (vma->vm_ops && vma->vm_ops->get_policy) ?
vma->vm_ops->get_policy(vma, addr, ilx) : vma->vm_policy;
}
/*
* get_vma_policy(@vma, @addr)
* get_vma_policy(@vma, @addr, @order, @ilx)
* @vma: virtual memory area whose policy is sought
* @addr: address in @vma for shared policy lookup
* @order: 0, or appropriate huge_page_order for interleaving
* @ilx: interleave index (output), for use only when MPOL_INTERLEAVE
*
* Returns effective policy for a VMA at specified address.
* Falls back to current->mempolicy or system default policy, as necessary.
@ -1726,14 +1715,18 @@ struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
* freeing by another task. It is the caller's responsibility to free the
* extra reference for shared policies.
*/
static struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
unsigned long addr)
struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
unsigned long addr, int order, pgoff_t *ilx)
{
struct mempolicy *pol = __get_vma_policy(vma, addr);
struct mempolicy *pol;
pol = __get_vma_policy(vma, addr, ilx);
if (!pol)
pol = get_task_policy(current);
if (pol->mode == MPOL_INTERLEAVE) {
*ilx += vma->vm_pgoff >> order;
*ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
}
return pol;
}
@ -1743,8 +1736,9 @@ bool vma_policy_mof(struct vm_area_struct *vma)
if (vma->vm_ops && vma->vm_ops->get_policy) {
bool ret = false;
pgoff_t ilx; /* ignored here */
pol = vma->vm_ops->get_policy(vma, vma->vm_start);
pol = vma->vm_ops->get_policy(vma, vma->vm_start, &ilx);
if (pol && (pol->flags & MPOL_F_MOF))
ret = true;
mpol_cond_put(pol);
@ -1779,54 +1773,6 @@ bool apply_policy_zone(struct mempolicy *policy, enum zone_type zone)
return zone >= dynamic_policy_zone;
}
/*
* Return a nodemask representing a mempolicy for filtering nodes for
* page allocation
*/
nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
{
int mode = policy->mode;
/* Lower zones don't get a nodemask applied for MPOL_BIND */
if (unlikely(mode == MPOL_BIND) &&
apply_policy_zone(policy, gfp_zone(gfp)) &&
cpuset_nodemask_valid_mems_allowed(&policy->nodes))
return &policy->nodes;
if (mode == MPOL_PREFERRED_MANY)
return &policy->nodes;
return NULL;
}
/*
* Return the preferred node id for 'prefer' mempolicy, and return
* the given id for all other policies.
*
* policy_node() is always coupled with policy_nodemask(), which
* secures the nodemask limit for 'bind' and 'prefer-many' policy.
*/
static int policy_node(gfp_t gfp, struct mempolicy *policy, int nid)
{
if (policy->mode == MPOL_PREFERRED) {
nid = first_node(policy->nodes);
} else {
/*
* __GFP_THISNODE shouldn't even be used with the bind policy
* because we might easily break the expectation to stay on the
* requested node and not break the policy.
*/
WARN_ON_ONCE(policy->mode == MPOL_BIND && (gfp & __GFP_THISNODE));
}
if ((policy->mode == MPOL_BIND ||
policy->mode == MPOL_PREFERRED_MANY) &&
policy->home_node != NUMA_NO_NODE)
return policy->home_node;
return nid;
}
/* Do dynamic interleaving for a process */
static unsigned int interleave_nodes(struct mempolicy *policy)
{
@ -1886,11 +1832,11 @@ unsigned int mempolicy_slab_node(void)
}
/*
* Do static interleaving for a VMA with known offset @n. Returns the n'th
* node in pol->nodes (starting from n=0), wrapping around if n exceeds the
* number of present nodes.
* Do static interleaving for interleave index @ilx. Returns the ilx'th
* node in pol->nodes (starting from ilx=0), wrapping around if ilx
* exceeds the number of present nodes.
*/
static unsigned offset_il_node(struct mempolicy *pol, unsigned long n)
static unsigned int interleave_nid(struct mempolicy *pol, pgoff_t ilx)
{
nodemask_t nodemask = pol->nodes;
unsigned int target, nnodes;
@ -1908,33 +1854,54 @@ static unsigned offset_il_node(struct mempolicy *pol, unsigned long n)
nnodes = nodes_weight(nodemask);
if (!nnodes)
return numa_node_id();
target = (unsigned int)n % nnodes;
target = ilx % nnodes;
nid = first_node(nodemask);
for (i = 0; i < target; i++)
nid = next_node(nid, nodemask);
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.
* Return a nodemask representing a mempolicy for filtering nodes for
* page allocation, together with preferred node id (or the input node id).
*/
BUG_ON(shift < PAGE_SHIFT);
off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
off += (addr - vma->vm_start) >> shift;
return offset_il_node(pol, off);
} else
return interleave_nodes(pol);
static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *pol,
pgoff_t ilx, int *nid)
{
nodemask_t *nodemask = NULL;
switch (pol->mode) {
case MPOL_PREFERRED:
/* Override input node id */
*nid = first_node(pol->nodes);
break;
case MPOL_PREFERRED_MANY:
nodemask = &pol->nodes;
if (pol->home_node != NUMA_NO_NODE)
*nid = pol->home_node;
break;
case MPOL_BIND:
/* Restrict to nodemask (but not on lower zones) */
if (apply_policy_zone(pol, gfp_zone(gfp)) &&
cpuset_nodemask_valid_mems_allowed(&pol->nodes))
nodemask = &pol->nodes;
if (pol->home_node != NUMA_NO_NODE)
*nid = pol->home_node;
/*
* __GFP_THISNODE shouldn't even be used with the bind policy
* because we might easily break the expectation to stay on the
* requested node and not break the policy.
*/
WARN_ON_ONCE(gfp & __GFP_THISNODE);
break;
case MPOL_INTERLEAVE:
/* Override input node id */
*nid = (ilx == NO_INTERLEAVE_INDEX) ?
interleave_nodes(pol) : interleave_nid(pol, ilx);
break;
}
return nodemask;
}
#ifdef CONFIG_HUGETLBFS
@ -1950,27 +1917,16 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
* to the struct mempolicy for conditional unref after allocation.
* If the effective policy is 'bind' or 'prefer-many', returns a pointer
* to the mempolicy's @nodemask for filtering the zonelist.
*
* Must be protected by read_mems_allowed_begin()
*/
int huge_node(struct vm_area_struct *vma, unsigned long addr, gfp_t gfp_flags,
struct mempolicy **mpol, nodemask_t **nodemask)
{
pgoff_t ilx;
int nid;
int mode;
*mpol = get_vma_policy(vma, addr);
*nodemask = NULL;
mode = (*mpol)->mode;
if (unlikely(mode == MPOL_INTERLEAVE)) {
nid = interleave_nid(*mpol, vma, addr,
huge_page_shift(hstate_vma(vma)));
} else {
nid = policy_node(gfp_flags, *mpol, numa_node_id());
if (mode == MPOL_BIND || mode == MPOL_PREFERRED_MANY)
*nodemask = &(*mpol)->nodes;
}
nid = numa_node_id();
*mpol = get_vma_policy(vma, addr, hstate_vma(vma)->order, &ilx);
*nodemask = policy_nodemask(gfp_flags, *mpol, ilx, &nid);
return nid;
}
@ -2048,27 +2004,8 @@ bool mempolicy_in_oom_domain(struct task_struct *tsk,
return ret;
}
/* 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 page *page;
page = __alloc_pages(gfp, order, nid, NULL);
/* skip NUMA_INTERLEAVE_HIT counter update if numa stats is disabled */
if (!static_branch_likely(&vm_numa_stat_key))
return page;
if (page && page_to_nid(page) == nid) {
preempt_disable();
__count_numa_event(page_zone(page), NUMA_INTERLEAVE_HIT);
preempt_enable();
}
return page;
}
static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order,
int nid, struct mempolicy *pol)
int nid, nodemask_t *nodemask)
{
struct page *page;
gfp_t preferred_gfp;
@ -2081,7 +2018,7 @@ static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order,
*/
preferred_gfp = gfp | __GFP_NOWARN;
preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL);
page = __alloc_pages(preferred_gfp, order, nid, &pol->nodes);
page = __alloc_pages(preferred_gfp, order, nid, nodemask);
if (!page)
page = __alloc_pages(gfp, order, nid, NULL);
@ -2089,55 +2026,29 @@ static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order,
}
/**
* vma_alloc_folio - Allocate a folio for a VMA.
* alloc_pages_mpol - Allocate pages according to NUMA mempolicy.
* @gfp: GFP flags.
* @order: Order of the folio.
* @vma: Pointer to VMA or NULL if not available.
* @addr: Virtual address of the allocation. Must be inside @vma.
* @hugepage: For hugepages try only the preferred node if possible.
* @order: Order of the page allocation.
* @pol: Pointer to the NUMA mempolicy.
* @ilx: Index for interleave mempolicy (also distinguishes alloc_pages()).
* @nid: Preferred node (usually numa_node_id() but @mpol may override it).
*
* Allocate a folio for a specific address in @vma, using the appropriate
* NUMA policy. When @vma is not NULL the caller must hold the mmap_lock
* of the mm_struct of the VMA to prevent it from going away. Should be
* used for all allocations for folios that will be mapped into user space.
*
* Return: The folio on success or NULL if allocation fails.
* Return: The page on success or NULL if allocation fails.
*/
struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
unsigned long addr, bool hugepage)
struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order,
struct mempolicy *pol, pgoff_t ilx, int nid)
{
struct mempolicy *pol;
int node = numa_node_id();
struct folio *folio;
int preferred_nid;
nodemask_t *nmask;
pol = get_vma_policy(vma, addr);
if (pol->mode == MPOL_INTERLEAVE) {
struct page *page;
unsigned nid;
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT + order);
mpol_cond_put(pol);
gfp |= __GFP_COMP;
page = alloc_page_interleave(gfp, order, nid);
return page_rmappable_folio(page);
}
if (pol->mode == MPOL_PREFERRED_MANY) {
nodemask_t *nodemask;
struct page *page;
node = policy_node(gfp, pol, node);
gfp |= __GFP_COMP;
page = alloc_pages_preferred_many(gfp, order, node, pol);
mpol_cond_put(pol);
return page_rmappable_folio(page);
}
nodemask = policy_nodemask(gfp, pol, ilx, &nid);
if (unlikely(IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hugepage)) {
int hpage_node = node;
if (pol->mode == MPOL_PREFERRED_MANY)
return alloc_pages_preferred_many(gfp, order, nid, nodemask);
if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) &&
/* filter "hugepage" allocation, unless from alloc_pages() */
order == HPAGE_PMD_ORDER && ilx != NO_INTERLEAVE_INDEX) {
/*
* For hugepage allocation and non-interleave policy which
* allows the current node (or other explicitly preferred
@ -2148,39 +2059,68 @@ struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
* If the policy is interleave or does not allow the current
* node in its nodemask, we allocate the standard way.
*/
if (pol->mode == MPOL_PREFERRED)
hpage_node = first_node(pol->nodes);
nmask = policy_nodemask(gfp, pol);
if (!nmask || node_isset(hpage_node, *nmask)) {
mpol_cond_put(pol);
if (pol->mode != MPOL_INTERLEAVE &&
(!nodemask || node_isset(nid, *nodemask))) {
/*
* First, try to allocate THP only on local node, but
* don't reclaim unnecessarily, just compact.
*/
folio = __folio_alloc_node(gfp | __GFP_THISNODE |
__GFP_NORETRY, order, hpage_node);
page = __alloc_pages_node(nid,
gfp | __GFP_THISNODE | __GFP_NORETRY, order);
if (page || !(gfp & __GFP_DIRECT_RECLAIM))
return page;
/*
* If hugepage allocations are configured to always
* synchronous compact or the vma has been madvised
* to prefer hugepage backing, retry allowing remote
* memory with both reclaim and compact as well.
*/
if (!folio && (gfp & __GFP_DIRECT_RECLAIM))
folio = __folio_alloc(gfp, order, hpage_node,
nmask);
goto out;
}
}
nmask = policy_nodemask(gfp, pol);
preferred_nid = policy_node(gfp, pol, node);
folio = __folio_alloc(gfp, order, preferred_nid, nmask);
page = __alloc_pages(gfp, order, nid, nodemask);
if (unlikely(pol->mode == MPOL_INTERLEAVE) && page) {
/* skip NUMA_INTERLEAVE_HIT update if numa stats is disabled */
if (static_branch_likely(&vm_numa_stat_key) &&
page_to_nid(page) == nid) {
preempt_disable();
__count_numa_event(page_zone(page), NUMA_INTERLEAVE_HIT);
preempt_enable();
}
}
return page;
}
/**
* vma_alloc_folio - Allocate a folio for a VMA.
* @gfp: GFP flags.
* @order: Order of the folio.
* @vma: Pointer to VMA.
* @addr: Virtual address of the allocation. Must be inside @vma.
* @hugepage: Unused (was: For hugepages try only preferred node if possible).
*
* Allocate a folio for a specific address in @vma, using the appropriate
* NUMA policy. The caller must hold the mmap_lock of the mm_struct of the
* VMA to prevent it from going away. Should be used for all allocations
* for folios that will be mapped into user space, excepting hugetlbfs, and
* excepting where direct use of alloc_pages_mpol() is more appropriate.
*
* Return: The folio on success or NULL if allocation fails.
*/
struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
unsigned long addr, bool hugepage)
{
struct mempolicy *pol;
pgoff_t ilx;
struct page *page;
pol = get_vma_policy(vma, addr, order, &ilx);
page = alloc_pages_mpol(gfp | __GFP_COMP, order,
pol, ilx, numa_node_id());
mpol_cond_put(pol);
out:
return folio;
return page_rmappable_folio(page);
}
EXPORT_SYMBOL(vma_alloc_folio);
@ -2198,33 +2138,23 @@ EXPORT_SYMBOL(vma_alloc_folio);
* flags are used.
* Return: The page on success or NULL if allocation fails.
*/
struct page *alloc_pages(gfp_t gfp, unsigned order)
struct page *alloc_pages(gfp_t gfp, unsigned int order)
{
struct mempolicy *pol = &default_policy;
struct page *page;
if (!in_interrupt() && !(gfp & __GFP_THISNODE))
pol = get_task_policy(current);
/*
* No reference counting needed for current->mempolicy
* nor system default_policy
*/
if (pol->mode == MPOL_INTERLEAVE)
page = alloc_page_interleave(gfp, order, interleave_nodes(pol));
else if (pol->mode == MPOL_PREFERRED_MANY)
page = alloc_pages_preferred_many(gfp, order,
policy_node(gfp, pol, numa_node_id()), pol);
else
page = __alloc_pages(gfp, order,
policy_node(gfp, pol, numa_node_id()),
policy_nodemask(gfp, pol));
if (!in_interrupt() && !(gfp & __GFP_THISNODE))
pol = get_task_policy(current);
return page;
return alloc_pages_mpol(gfp, order,
pol, NO_INTERLEAVE_INDEX, numa_node_id());
}
EXPORT_SYMBOL(alloc_pages);
struct folio *folio_alloc(gfp_t gfp, unsigned order)
struct folio *folio_alloc(gfp_t gfp, unsigned int order)
{
return page_rmappable_folio(alloc_pages(gfp | __GFP_COMP, order));
}
@ -2295,6 +2225,8 @@ unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
unsigned long nr_pages, struct page **page_array)
{
struct mempolicy *pol = &default_policy;
nodemask_t *nodemask;
int nid;
if (!in_interrupt() && !(gfp & __GFP_THISNODE))
pol = get_task_policy(current);
@ -2307,9 +2239,10 @@ unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
return alloc_pages_bulk_array_preferred_many(gfp,
numa_node_id(), pol, nr_pages, page_array);
return __alloc_pages_bulk(gfp, policy_node(gfp, pol, numa_node_id()),
policy_nodemask(gfp, pol), nr_pages, NULL,
page_array);
nid = numa_node_id();
nodemask = policy_nodemask(gfp, pol, NO_INTERLEAVE_INDEX, &nid);
return __alloc_pages_bulk(gfp, nid, nodemask,
nr_pages, NULL, page_array);
}
int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
@ -2496,23 +2429,21 @@ int mpol_misplaced(struct folio *folio, struct vm_area_struct *vma,
unsigned long addr)
{
struct mempolicy *pol;
pgoff_t ilx;
struct zoneref *z;
int curnid = folio_nid(folio);
unsigned long pgoff;
int thiscpu = raw_smp_processor_id();
int thisnid = cpu_to_node(thiscpu);
int polnid = NUMA_NO_NODE;
int ret = NUMA_NO_NODE;
pol = get_vma_policy(vma, addr);
pol = get_vma_policy(vma, addr, folio_order(folio), &ilx);
if (!(pol->flags & MPOL_F_MOF))
goto out;
switch (pol->mode) {
case MPOL_INTERLEAVE:
pgoff = vma->vm_pgoff;
pgoff += (addr - vma->vm_start) >> PAGE_SHIFT;
polnid = offset_il_node(pol, pgoff);
polnid = interleave_nid(pol, ilx);
break;
case MPOL_PREFERRED:

View File

@ -1544,38 +1544,20 @@ static inline struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
return NULL;
}
#endif /* CONFIG_NUMA && CONFIG_TMPFS */
#ifndef CONFIG_NUMA
#define vm_policy vm_private_data
#endif
static void shmem_pseudo_vma_init(struct vm_area_struct *vma,
static struct mempolicy *shmem_get_pgoff_policy(struct shmem_inode_info *info,
pgoff_t index, unsigned int order, pgoff_t *ilx);
static struct folio *shmem_swapin_cluster(swp_entry_t swap, gfp_t gfp,
struct shmem_inode_info *info, pgoff_t index)
{
/* Create a pseudo vma that just contains the policy */
vma_init(vma, NULL);
/* Bias interleave by inode number to distribute better across nodes */
vma->vm_pgoff = index + info->vfs_inode.i_ino;
vma->vm_policy = mpol_shared_policy_lookup(&info->policy, index);
}
static void shmem_pseudo_vma_destroy(struct vm_area_struct *vma)
{
/* Drop reference taken by mpol_shared_policy_lookup() */
mpol_cond_put(vma->vm_policy);
}
static struct folio *shmem_swapin(swp_entry_t swap, gfp_t gfp,
struct shmem_inode_info *info, pgoff_t index)
{
struct vm_area_struct pvma;
struct mempolicy *mpol;
pgoff_t ilx;
struct page *page;
struct vm_fault vmf = {
.vma = &pvma,
};
shmem_pseudo_vma_init(&pvma, info, index);
page = swap_cluster_readahead(swap, gfp, &vmf);
shmem_pseudo_vma_destroy(&pvma);
mpol = shmem_get_pgoff_policy(info, index, 0, &ilx);
page = swap_cluster_readahead(swap, gfp, mpol, ilx);
mpol_cond_put(mpol);
if (!page)
return NULL;
@ -1609,27 +1591,29 @@ static gfp_t limit_gfp_mask(gfp_t huge_gfp, gfp_t limit_gfp)
static struct folio *shmem_alloc_hugefolio(gfp_t gfp,
struct shmem_inode_info *info, pgoff_t index)
{
struct vm_area_struct pvma;
struct folio *folio;
struct mempolicy *mpol;
pgoff_t ilx;
struct page *page;
shmem_pseudo_vma_init(&pvma, info, index);
folio = vma_alloc_folio(gfp, HPAGE_PMD_ORDER, &pvma, 0, true);
shmem_pseudo_vma_destroy(&pvma);
mpol = shmem_get_pgoff_policy(info, index, HPAGE_PMD_ORDER, &ilx);
page = alloc_pages_mpol(gfp, HPAGE_PMD_ORDER, mpol, ilx, numa_node_id());
mpol_cond_put(mpol);
return folio;
return page_rmappable_folio(page);
}
static struct folio *shmem_alloc_folio(gfp_t gfp,
struct shmem_inode_info *info, pgoff_t index)
{
struct vm_area_struct pvma;
struct folio *folio;
struct mempolicy *mpol;
pgoff_t ilx;
struct page *page;
shmem_pseudo_vma_init(&pvma, info, index);
folio = vma_alloc_folio(gfp, 0, &pvma, 0, false);
shmem_pseudo_vma_destroy(&pvma);
mpol = shmem_get_pgoff_policy(info, index, 0, &ilx);
page = alloc_pages_mpol(gfp, 0, mpol, ilx, numa_node_id());
mpol_cond_put(mpol);
return folio;
return (struct folio *)page;
}
static struct folio *shmem_alloc_and_add_folio(gfp_t gfp,
@ -1883,7 +1867,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
count_memcg_event_mm(fault_mm, PGMAJFAULT);
}
/* Here we actually start the io */
folio = shmem_swapin(swap, gfp, info, index);
folio = shmem_swapin_cluster(swap, gfp, info, index);
if (!folio) {
error = -ENOMEM;
goto failed;
@ -2334,15 +2318,41 @@ static int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *mpol)
}
static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
unsigned long addr)
unsigned long addr, pgoff_t *ilx)
{
struct inode *inode = file_inode(vma->vm_file);
pgoff_t index;
/*
* Bias interleave by inode number to distribute better across nodes;
* but this interface is independent of which page order is used, so
* supplies only that bias, letting caller apply the offset (adjusted
* by page order, as in shmem_get_pgoff_policy() and get_vma_policy()).
*/
*ilx = inode->i_ino;
index = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy, index);
}
#endif
static struct mempolicy *shmem_get_pgoff_policy(struct shmem_inode_info *info,
pgoff_t index, unsigned int order, pgoff_t *ilx)
{
struct mempolicy *mpol;
/* Bias interleave by inode number to distribute better across nodes */
*ilx = info->vfs_inode.i_ino + (index >> order);
mpol = mpol_shared_policy_lookup(&info->policy, index);
return mpol ? mpol : get_task_policy(current);
}
#else
static struct mempolicy *shmem_get_pgoff_policy(struct shmem_inode_info *info,
pgoff_t index, unsigned int order, pgoff_t *ilx)
{
*ilx = 0;
return NULL;
}
#endif /* CONFIG_NUMA */
int shmem_lock(struct file *file, int lock, struct ucounts *ucounts)
{

View File

@ -2,6 +2,8 @@
#ifndef _MM_SWAP_H
#define _MM_SWAP_H
struct mempolicy;
#ifdef CONFIG_SWAP
#include <linux/blk_types.h> /* for bio_end_io_t */
@ -48,11 +50,10 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
unsigned long addr,
struct swap_iocb **plug);
struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
struct vm_area_struct *vma,
unsigned long addr,
struct mempolicy *mpol, pgoff_t ilx,
bool *new_page_allocated);
struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
struct vm_fault *vmf);
struct mempolicy *mpol, pgoff_t ilx);
struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
struct vm_fault *vmf);
@ -80,7 +81,7 @@ static inline void show_swap_cache_info(void)
}
static inline struct page *swap_cluster_readahead(swp_entry_t entry,
gfp_t gfp_mask, struct vm_fault *vmf)
gfp_t gfp_mask, struct mempolicy *mpol, pgoff_t ilx)
{
return NULL;
}

View File

@ -10,6 +10,7 @@
#include <linux/mm.h>
#include <linux/gfp.h>
#include <linux/kernel_stat.h>
#include <linux/mempolicy.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/init.h>
@ -410,7 +411,7 @@ struct folio *filemap_get_incore_folio(struct address_space *mapping,
}
struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
struct vm_area_struct *vma, unsigned long addr,
struct mempolicy *mpol, pgoff_t ilx,
bool *new_page_allocated)
{
struct swap_info_struct *si;
@ -453,7 +454,8 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
* before marking swap_map SWAP_HAS_CACHE, when -EEXIST will
* cause any racers to loop around until we add it to cache.
*/
folio = vma_alloc_folio(gfp_mask, 0, vma, addr, false);
folio = (struct folio *)alloc_pages_mpol(gfp_mask, 0,
mpol, ilx, numa_node_id());
if (!folio)
goto fail_put_swap;
@ -528,14 +530,19 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
struct vm_area_struct *vma,
unsigned long addr, struct swap_iocb **plug)
{
bool page_was_allocated;
struct page *retpage = __read_swap_cache_async(entry, gfp_mask,
vma, addr, &page_was_allocated);
bool page_allocated;
struct mempolicy *mpol;
pgoff_t ilx;
struct page *page;
if (page_was_allocated)
swap_readpage(retpage, false, plug);
mpol = get_vma_policy(vma, addr, 0, &ilx);
page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated);
mpol_cond_put(mpol);
return retpage;
if (page_allocated)
swap_readpage(page, false, plug);
return page;
}
static unsigned int __swapin_nr_pages(unsigned long prev_offset,
@ -603,7 +610,8 @@ static unsigned long swapin_nr_pages(unsigned long offset)
* swap_cluster_readahead - swap in pages in hope we need them soon
* @entry: swap entry of this memory
* @gfp_mask: memory allocation flags
* @vmf: fault information
* @mpol: NUMA memory allocation policy to be applied
* @ilx: NUMA interleave index, for use only when MPOL_INTERLEAVE
*
* Returns the struct page for entry and addr, after queueing swapin.
*
@ -612,13 +620,12 @@ static unsigned long swapin_nr_pages(unsigned long offset)
* because it doesn't cost us any seek time. We also make sure to queue
* the 'original' request together with the readahead ones...
*
* This has been extended to use the NUMA policies from the mm triggering
* the readahead.
*
* Caller must hold read mmap_lock if vmf->vma is not NULL.
* Note: it is intentional that the same NUMA policy and interleave index
* are used for every page of the readahead: neighbouring pages on swap
* are fairly likely to have been swapped out from the same node.
*/
struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
struct vm_fault *vmf)
struct mempolicy *mpol, pgoff_t ilx)
{
struct page *page;
unsigned long entry_offset = swp_offset(entry);
@ -629,8 +636,6 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
struct blk_plug plug;
struct swap_iocb *splug = NULL;
bool page_allocated;
struct vm_area_struct *vma = vmf->vma;
unsigned long addr = vmf->address;
mask = swapin_nr_pages(offset) - 1;
if (!mask)
@ -649,7 +654,7 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
/* Ok, do the async read-ahead now */
page = __read_swap_cache_async(
swp_entry(swp_type(entry), offset),
gfp_mask, vma, addr, &page_allocated);
gfp_mask, mpol, ilx, &page_allocated);
if (!page)
continue;
if (page_allocated) {
@ -663,11 +668,14 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
}
blk_finish_plug(&plug);
swap_read_unplug(splug);
lru_add_drain(); /* Push any new pages onto the LRU now */
skip:
/* The page was likely read above, so no need for plugging here */
return read_swap_cache_async(entry, gfp_mask, vma, addr, NULL);
page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated);
if (unlikely(page_allocated))
swap_readpage(page, false, NULL);
return page;
}
int init_swap_address_space(unsigned int type, unsigned long nr_pages)
@ -765,8 +773,10 @@ static void swap_ra_info(struct vm_fault *vmf,
/**
* swap_vma_readahead - swap in pages in hope we need them soon
* @fentry: swap entry of this memory
* @targ_entry: swap entry of the targeted memory
* @gfp_mask: memory allocation flags
* @mpol: NUMA memory allocation policy to be applied
* @targ_ilx: NUMA interleave index, for use only when MPOL_INTERLEAVE
* @vmf: fault information
*
* Returns the struct page for entry and addr, after queueing swapin.
@ -777,16 +787,17 @@ static void swap_ra_info(struct vm_fault *vmf,
* Caller must hold read mmap_lock if vmf->vma is not NULL.
*
*/
static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
static struct page *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask,
struct mempolicy *mpol, pgoff_t targ_ilx,
struct vm_fault *vmf)
{
struct blk_plug plug;
struct swap_iocb *splug = NULL;
struct vm_area_struct *vma = vmf->vma;
struct page *page;
pte_t *pte = NULL, pentry;
unsigned long addr;
swp_entry_t entry;
pgoff_t ilx;
unsigned int i;
bool page_allocated;
struct vma_swap_readahead ra_info = {
@ -798,9 +809,10 @@ static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
goto skip;
addr = vmf->address - (ra_info.offset * PAGE_SIZE);
ilx = targ_ilx - ra_info.offset;
blk_start_plug(&plug);
for (i = 0; i < ra_info.nr_pte; i++, addr += PAGE_SIZE) {
for (i = 0; i < ra_info.nr_pte; i++, ilx++, addr += PAGE_SIZE) {
if (!pte++) {
pte = pte_offset_map(vmf->pmd, addr);
if (!pte)
@ -814,8 +826,8 @@ static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
continue;
pte_unmap(pte);
pte = NULL;
page = __read_swap_cache_async(entry, gfp_mask, vma,
addr, &page_allocated);
page = __read_swap_cache_async(entry, gfp_mask, mpol, ilx,
&page_allocated);
if (!page)
continue;
if (page_allocated) {
@ -834,8 +846,11 @@ static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
lru_add_drain();
skip:
/* The page was likely read above, so no need for plugging here */
return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address,
NULL);
page = __read_swap_cache_async(targ_entry, gfp_mask, mpol, targ_ilx,
&page_allocated);
if (unlikely(page_allocated))
swap_readpage(page, false, NULL);
return page;
}
/**
@ -853,9 +868,16 @@ static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask,
struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
struct vm_fault *vmf)
{
return swap_use_vma_readahead() ?
swap_vma_readahead(entry, gfp_mask, vmf) :
swap_cluster_readahead(entry, gfp_mask, vmf);
struct mempolicy *mpol;
pgoff_t ilx;
struct page *page;
mpol = get_vma_policy(vmf->vma, vmf->address, 0, &ilx);
page = swap_use_vma_readahead() ?
swap_vma_readahead(entry, gfp_mask, mpol, ilx, vmf) :
swap_cluster_readahead(entry, gfp_mask, mpol, ilx);
mpol_cond_put(mpol);
return page;
}
#ifdef CONFIG_SYSFS

View File

@ -24,6 +24,7 @@
#include <linux/swap.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
#include <linux/mempolicy.h>
#include <linux/mempool.h>
#include <linux/zpool.h>
#include <crypto/acompress.h>
@ -1057,6 +1058,7 @@ static int zswap_writeback_entry(struct zswap_entry *entry,
{
swp_entry_t swpentry = entry->swpentry;
struct page *page;
struct mempolicy *mpol;
struct scatterlist input, output;
struct crypto_acomp_ctx *acomp_ctx;
struct zpool *pool = zswap_find_zpool(entry);
@ -1075,8 +1077,9 @@ static int zswap_writeback_entry(struct zswap_entry *entry,
}
/* try to allocate swap cache page */
page = __read_swap_cache_async(swpentry, GFP_KERNEL, NULL, 0,
&page_was_allocated);
mpol = get_task_policy(current);
page = __read_swap_cache_async(swpentry, GFP_KERNEL, mpol,
NO_INTERLEAVE_INDEX, &page_was_allocated);
if (!page) {
ret = -ENOMEM;
goto fail;