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-rw-r--r--mm/hugetlb.c4
-rw-r--r--mm/mempolicy.c79
-rw-r--r--mm/slub.c38
3 files changed, 96 insertions, 25 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index de4cf458d6e..84c795ee2d6 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -71,8 +71,9 @@ static struct page *dequeue_huge_page(struct vm_area_struct *vma,
{
int nid;
struct page *page = NULL;
+ struct mempolicy *mpol;
struct zonelist *zonelist = huge_zonelist(vma, address,
- htlb_alloc_mask);
+ htlb_alloc_mask, &mpol);
struct zone **z;
for (z = zonelist->zones; *z; z++) {
@@ -87,6 +88,7 @@ static struct page *dequeue_huge_page(struct vm_area_struct *vma,
break;
}
}
+ mpol_free(mpol); /* unref if mpol !NULL */
return page;
}
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index bb54b88c3d5..3d6ac9505d0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1077,21 +1077,37 @@ asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
#endif
-/* Return effective policy for a VMA */
+/*
+ * get_vma_policy(@task, @vma, @addr)
+ * @task - task for fallback if vma policy == default
+ * @vma - virtual memory area whose policy is sought
+ * @addr - address in @vma for shared policy lookup
+ *
+ * Returns effective policy for a VMA at specified address.
+ * Falls back to @task or system default policy, as necessary.
+ * Returned policy has extra reference count if shared, vma,
+ * or some other task's policy [show_numa_maps() can pass
+ * @task != current]. It is the caller's responsibility to
+ * free the reference in these cases.
+ */
static struct mempolicy * get_vma_policy(struct task_struct *task,
struct vm_area_struct *vma, unsigned long addr)
{
struct mempolicy *pol = task->mempolicy;
+ int shared_pol = 0;
if (vma) {
- if (vma->vm_ops && vma->vm_ops->get_policy)
+ if (vma->vm_ops && vma->vm_ops->get_policy) {
pol = vma->vm_ops->get_policy(vma, addr);
- else if (vma->vm_policy &&
+ shared_pol = 1; /* if pol non-NULL, add ref below */
+ } else if (vma->vm_policy &&
vma->vm_policy->policy != MPOL_DEFAULT)
pol = vma->vm_policy;
}
if (!pol)
pol = &default_policy;
+ else if (!shared_pol && pol != current->mempolicy)
+ mpol_get(pol); /* vma or other task's policy */
return pol;
}
@@ -1207,19 +1223,45 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
}
#ifdef CONFIG_HUGETLBFS
-/* Return a zonelist suitable for a huge page allocation. */
+/*
+ * huge_zonelist(@vma, @addr, @gfp_flags, @mpol)
+ * @vma = virtual memory area whose policy is sought
+ * @addr = address in @vma for shared policy lookup and interleave policy
+ * @gfp_flags = for requested zone
+ * @mpol = pointer to mempolicy pointer for reference counted 'BIND policy
+ *
+ * Returns a zonelist suitable for a huge page allocation.
+ * If the effective policy is 'BIND, returns pointer to policy's zonelist.
+ * If it is also a policy for which get_vma_policy() returns an extra
+ * reference, we must hold that reference until after allocation.
+ * In that case, return policy via @mpol so hugetlb allocation can drop
+ * the reference. For non-'BIND referenced policies, we can/do drop the
+ * reference here, so the caller doesn't need to know about the special case
+ * for default and current task policy.
+ */
struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
- gfp_t gfp_flags)
+ gfp_t gfp_flags, struct mempolicy **mpol)
{
struct mempolicy *pol = get_vma_policy(current, vma, addr);
+ struct zonelist *zl;
+ *mpol = NULL; /* probably no unref needed */
if (pol->policy == MPOL_INTERLEAVE) {
unsigned nid;
nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
+ __mpol_free(pol); /* finished with pol */
return NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_flags);
}
- return zonelist_policy(GFP_HIGHUSER, pol);
+
+ zl = zonelist_policy(GFP_HIGHUSER, pol);
+ if (unlikely(pol != &default_policy && pol != current->mempolicy)) {
+ if (pol->policy != MPOL_BIND)
+ __mpol_free(pol); /* finished with pol */
+ else
+ *mpol = pol; /* unref needed after allocation */
+ }
+ return zl;
}
#endif
@@ -1264,6 +1306,7 @@ struct page *
alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
{
struct mempolicy *pol = get_vma_policy(current, vma, addr);
+ struct zonelist *zl;
cpuset_update_task_memory_state();
@@ -1273,7 +1316,19 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
return alloc_page_interleave(gfp, 0, nid);
}
- return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol));
+ zl = zonelist_policy(gfp, pol);
+ if (pol != &default_policy && pol != current->mempolicy) {
+ /*
+ * slow path: ref counted policy -- shared or vma
+ */
+ struct page *page = __alloc_pages(gfp, 0, zl);
+ __mpol_free(pol);
+ return page;
+ }
+ /*
+ * fast path: default or task policy
+ */
+ return __alloc_pages(gfp, 0, zl);
}
/**
@@ -1872,6 +1927,7 @@ int show_numa_map(struct seq_file *m, void *v)
struct numa_maps *md;
struct file *file = vma->vm_file;
struct mm_struct *mm = vma->vm_mm;
+ struct mempolicy *pol;
int n;
char buffer[50];
@@ -1882,8 +1938,13 @@ int show_numa_map(struct seq_file *m, void *v)
if (!md)
return 0;
- mpol_to_str(buffer, sizeof(buffer),
- get_vma_policy(priv->task, vma, vma->vm_start));
+ pol = get_vma_policy(priv->task, vma, vma->vm_start);
+ mpol_to_str(buffer, sizeof(buffer), pol);
+ /*
+ * unref shared or other task's mempolicy
+ */
+ if (pol != &default_policy && pol != current->mempolicy)
+ __mpol_free(pol);
seq_printf(m, "%08lx %s", vma->vm_start, buffer);
diff --git a/mm/slub.c b/mm/slub.c
index 7defe84e6bd..addb20a6d67 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -986,7 +986,9 @@ out:
__setup("slub_debug", setup_slub_debug);
-static void kmem_cache_open_debug_check(struct kmem_cache *s)
+static unsigned long kmem_cache_flags(unsigned long objsize,
+ unsigned long flags, const char *name,
+ void (*ctor)(void *, struct kmem_cache *, unsigned long))
{
/*
* The page->offset field is only 16 bit wide. This is an offset
@@ -1000,19 +1002,21 @@ static void kmem_cache_open_debug_check(struct kmem_cache *s)
* Debugging or ctor may create a need to move the free
* pointer. Fail if this happens.
*/
- if (s->objsize >= 65535 * sizeof(void *)) {
- BUG_ON(s->flags & (SLAB_RED_ZONE | SLAB_POISON |
+ if (objsize >= 65535 * sizeof(void *)) {
+ BUG_ON(flags & (SLAB_RED_ZONE | SLAB_POISON |
SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
- BUG_ON(s->ctor);
- }
- else
+ BUG_ON(ctor);
+ } else {
/*
* Enable debugging if selected on the kernel commandline.
*/
if (slub_debug && (!slub_debug_slabs ||
- strncmp(slub_debug_slabs, s->name,
+ strncmp(slub_debug_slabs, name,
strlen(slub_debug_slabs)) == 0))
- s->flags |= slub_debug;
+ flags |= slub_debug;
+ }
+
+ return flags;
}
#else
static inline void setup_object_debug(struct kmem_cache *s,
@@ -1029,7 +1033,12 @@ static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
static inline int check_object(struct kmem_cache *s, struct page *page,
void *object, int active) { return 1; }
static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
-static inline void kmem_cache_open_debug_check(struct kmem_cache *s) {}
+static inline unsigned long kmem_cache_flags(unsigned long objsize,
+ unsigned long flags, const char *name,
+ void (*ctor)(void *, struct kmem_cache *, unsigned long))
+{
+ return flags;
+}
#define slub_debug 0
#endif
/*
@@ -2088,9 +2097,8 @@ static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
s->name = name;
s->ctor = ctor;
s->objsize = size;
- s->flags = flags;
s->align = align;
- kmem_cache_open_debug_check(s);
+ s->flags = kmem_cache_flags(size, flags, name, ctor);
if (!calculate_sizes(s))
goto error;
@@ -2660,7 +2668,7 @@ static int slab_unmergeable(struct kmem_cache *s)
}
static struct kmem_cache *find_mergeable(size_t size,
- size_t align, unsigned long flags,
+ size_t align, unsigned long flags, const char *name,
void (*ctor)(void *, struct kmem_cache *, unsigned long))
{
struct kmem_cache *s;
@@ -2674,6 +2682,7 @@ static struct kmem_cache *find_mergeable(size_t size,
size = ALIGN(size, sizeof(void *));
align = calculate_alignment(flags, align, size);
size = ALIGN(size, align);
+ flags = kmem_cache_flags(size, flags, name, NULL);
list_for_each_entry(s, &slab_caches, list) {
if (slab_unmergeable(s))
@@ -2682,8 +2691,7 @@ static struct kmem_cache *find_mergeable(size_t size,
if (size > s->size)
continue;
- if (((flags | slub_debug) & SLUB_MERGE_SAME) !=
- (s->flags & SLUB_MERGE_SAME))
+ if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
continue;
/*
* Check if alignment is compatible.
@@ -2707,7 +2715,7 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size,
struct kmem_cache *s;
down_write(&slub_lock);
- s = find_mergeable(size, align, flags, ctor);
+ s = find_mergeable(size, align, flags, name, ctor);
if (s) {
s->refcount++;
/*