Re: [PATCH v3 10/12] mempolicy: alloc_pages_mpol() for NUMA policy without vma
From: domenico cerasuolo
Date: Mon Oct 23 2023 - 12:53:47 EST
Il giorno ven 20 ott 2023 alle ore 00:05 Hugh Dickins
<hughd@xxxxxxxxxx> ha scritto:
>
> 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 09c231cb8bfd
> ("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.
>
> Link: https://lkml.kernel.org/r/74e34633-6060-f5e3-aee-7040d43f2e93@xxxxxxxxxx
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> Cc: Christoph Lameter <cl@xxxxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Huang Ying <ying.huang@xxxxxxxxx>
> Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> Cc: Nhat Pham <nphamcs@xxxxxxxxx>
> Cc: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Cc: Tejun heo <tj@xxxxxxxxxx>
> Cc: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
> Cc: Yang Shi <shy828301@xxxxxxxxx>
> Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> ---
> Rebased to mm.git's current mm-stable, to resolve with removal of
> vma_policy() from include/linux/mempolicy.h, and temporary omission
> of Nhat's ZSWAP mods from mm/swap_state.c: no other changes.
Hi Hugh,
not sure if it's the rebase, but I don't see an update to
__read_swap_cache_async invocation in zswap.c at line 1078. Shouldn't we pass a
mempolicy there too?
Thanks,
Domenico
>
> git cherry-pick 800caf44af25^..237d4ce921f0 # applies mm-unstable's 01-09
> then apply this "mempolicy: alloc_pages_mpol() for NUMA policy without vma"
> git cherry-pick e4fb3362b782^..ec6412928b8e # applies mm-unstable's 11-12
>
> fs/proc/task_mmu.c | 5 +-
> include/linux/gfp.h | 10 +-
> include/linux/mempolicy.h | 13 +-
> include/linux/mm.h | 2 +-
> ipc/shm.c | 21 +--
> mm/mempolicy.c | 383 +++++++++++++++++++---------------------------
> mm/shmem.c | 92 ++++++-----
> mm/swap.h | 9 +-
> mm/swap_state.c | 86 +++++++----
> 9 files changed, 299 insertions(+), 322 deletions(-)
>
> diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
> index 1d99450..66ae1c2 100644
> --- a/fs/proc/task_mmu.c
> +++ b/fs/proc/task_mmu.c
> @@ -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);
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index 665f066..f74f8d0 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -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());
> diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
> index acdb12f..2801d5b 100644
> --- a/include/linux/mempolicy.h
> +++ b/include/linux/mempolicy.h
> @@ -126,7 +126,9 @@ 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 +142,6 @@ 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;
> @@ -213,6 +213,13 @@ static inline void mpol_free_shared_policy(struct shared_policy *sp)
> 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)
> {
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 86e040e..b4d67a8 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -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
> diff --git a/ipc/shm.c b/ipc/shm.c
> index 576a543..222aaf0 100644
> --- a/ipc/shm.c
> +++ b/ipc/shm.c
> @@ -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
>
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index 596d580..8df0503 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -114,6 +114,8 @@
> #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
> #define MPOL_MF_WRLOCK (MPOL_MF_INTERNAL << 2) /* Write-lock walked vmas */
>
> +#define NO_INTERLEAVE_INDEX (-1UL)
> +
> static struct kmem_cache *policy_cache;
> static struct kmem_cache *sn_cache;
>
> @@ -898,6 +900,7 @@ 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 +912,7 @@ 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 +1170,15 @@ 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 +1187,6 @@ 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 +1696,19 @@ 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 +1717,18 @@ 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 +1738,9 @@ 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 +1775,6 @@ 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 +1834,11 @@ 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 +1856,54 @@ 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)
> +/*
> + * Return a nodemask representing a mempolicy for filtering nodes for
> + * page allocation, together with preferred node id (or the input node id).
> + */
> +static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *pol,
> + pgoff_t ilx, int *nid)
> {
> - if (vma) {
> - unsigned long off;
> + 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;
> /*
> - * 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.
> + * __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.
> */
> - 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);
> + 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 +1919,16 @@ 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)
> + 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 +2006,8 @@ 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 +2020,7 @@ 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 +2028,29 @@ 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;
> + nodemask_t *nodemask;
> + struct page *page;
>
> - pol = get_vma_policy(vma, addr);
> + nodemask = policy_nodemask(gfp, pol, ilx, &nid);
>
> - 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) {
> - 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);
> - }
> -
> - 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 +2061,68 @@ 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 +2140,23 @@ struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
> * 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 +2227,8 @@ 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 +2241,10 @@ 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 +2431,21 @@ 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:
> diff --git a/mm/shmem.c b/mm/shmem.c
> index bcbe9db..a314a25 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -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,
> - 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 struct mempolicy *shmem_get_pgoff_policy(struct shmem_inode_info *info,
> + pgoff_t index, unsigned int order, pgoff_t *ilx);
>
> -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,
> +static struct folio *shmem_swapin_cluster(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)
> {
> diff --git a/mm/swap.h b/mm/swap.h
> index 8a3c7a0..73c332e 100644
> --- a/mm/swap.h
> +++ b/mm/swap.h
> @@ -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;
> }
> diff --git a/mm/swap_state.c b/mm/swap_state.c
> index b3b14bd..a421f01 100644
> --- a/mm/swap_state.c
> +++ b/mm/swap_state.c
> @@ -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>
> @@ -410,8 +411,8 @@ 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,
> - bool *new_page_allocated)
> + struct mempolicy *mpol, pgoff_t ilx,
> + bool *new_page_allocated)
> {
> struct swap_info_struct *si;
> struct folio *folio;
> @@ -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)
> @@ -648,8 +653,8 @@ struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask,
> for (offset = start_offset; offset <= end_offset ; offset++) {
> /* Ok, do the async read-ahead now */
> page = __read_swap_cache_async(
> - swp_entry(swp_type(entry), offset),
> - gfp_mask, vma, addr, &page_allocated);
> + swp_entry(swp_type(entry), offset),
> + 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
> --
> 1.8.4.5
>