#include <linux/nodemask.h>
#include <linux/pagemap.h>
#include <linux/mempolicy.h>
+#include <linux/compiler.h>
#include <linux/cpuset.h>
#include <linux/mutex.h>
#include <linux/bootmem.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/page-isolation.h>
+#include <linux/jhash.h>
#include <asm/page.h>
#include <asm/pgtable.h>
*/
DEFINE_SPINLOCK(hugetlb_lock);
+/*
+ * Serializes faults on the same logical page. This is used to
+ * prevent spurious OOMs when the hugepage pool is fully utilized.
+ */
+static int num_fault_mutexes;
+static struct mutex *htlb_fault_mutex_table ____cacheline_aligned_in_smp;
+
static inline void unlock_or_release_subpool(struct hugepage_subpool *spool)
{
bool free = (spool->count == 0) && (spool->used_hpages == 0);
* Region tracking -- allows tracking of reservations and instantiated pages
* across the pages in a mapping.
*
- * The region data structures are protected by a combination of the mmap_sem
- * and the hugetlb_instantiation_mutex. To access or modify a region the caller
- * must either hold the mmap_sem for write, or the mmap_sem for read and
- * the hugetlb_instantiation_mutex:
- *
- * down_write(&mm->mmap_sem);
- * or
- * down_read(&mm->mmap_sem);
- * mutex_lock(&hugetlb_instantiation_mutex);
+ * The region data structures are embedded into a resv_map and
+ * protected by a resv_map's lock
*/
struct file_region {
struct list_head link;
long to;
};
-static long region_add(struct list_head *head, long f, long t)
+static long region_add(struct resv_map *resv, long f, long t)
{
+ struct list_head *head = &resv->regions;
struct file_region *rg, *nrg, *trg;
+ spin_lock(&resv->lock);
/* Locate the region we are either in or before. */
list_for_each_entry(rg, head, link)
if (f <= rg->to)
}
nrg->from = f;
nrg->to = t;
+ spin_unlock(&resv->lock);
return 0;
}
-static long region_chg(struct list_head *head, long f, long t)
+static long region_chg(struct resv_map *resv, long f, long t)
{
- struct file_region *rg, *nrg;
+ struct list_head *head = &resv->regions;
+ struct file_region *rg, *nrg = NULL;
long chg = 0;
+retry:
+ spin_lock(&resv->lock);
/* Locate the region we are before or in. */
list_for_each_entry(rg, head, link)
if (f <= rg->to)
* Subtle, allocate a new region at the position but make it zero
* size such that we can guarantee to record the reservation. */
if (&rg->link == head || t < rg->from) {
- nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
- if (!nrg)
- return -ENOMEM;
- nrg->from = f;
- nrg->to = f;
- INIT_LIST_HEAD(&nrg->link);
- list_add(&nrg->link, rg->link.prev);
+ if (!nrg) {
+ spin_unlock(&resv->lock);
+ nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
+ if (!nrg)
+ return -ENOMEM;
+
+ nrg->from = f;
+ nrg->to = f;
+ INIT_LIST_HEAD(&nrg->link);
+ goto retry;
+ }
- return t - f;
+ list_add(&nrg->link, rg->link.prev);
+ chg = t - f;
+ goto out_nrg;
}
/* Round our left edge to the current segment if it encloses us. */
if (&rg->link == head)
break;
if (rg->from > t)
- return chg;
+ goto out;
/* We overlap with this area, if it extends further than
* us then we must extend ourselves. Account for its
}
chg -= rg->to - rg->from;
}
+
+out:
+ spin_unlock(&resv->lock);
+ /* We already know we raced and no longer need the new region */
+ kfree(nrg);
+ return chg;
+out_nrg:
+ spin_unlock(&resv->lock);
return chg;
}
-static long region_truncate(struct list_head *head, long end)
+static long region_truncate(struct resv_map *resv, long end)
{
+ struct list_head *head = &resv->regions;
struct file_region *rg, *trg;
long chg = 0;
+ spin_lock(&resv->lock);
/* Locate the region we are either in or before. */
list_for_each_entry(rg, head, link)
if (end <= rg->to)
break;
if (&rg->link == head)
- return 0;
+ goto out;
/* If we are in the middle of a region then adjust it. */
if (end > rg->from) {
list_del(&rg->link);
kfree(rg);
}
+
+out:
+ spin_unlock(&resv->lock);
return chg;
}
-static long region_count(struct list_head *head, long f, long t)
+static long region_count(struct resv_map *resv, long f, long t)
{
+ struct list_head *head = &resv->regions;
struct file_region *rg;
long chg = 0;
+ spin_lock(&resv->lock);
/* Locate each segment we overlap with, and count that overlap. */
list_for_each_entry(rg, head, link) {
long seg_from;
chg += seg_to - seg_from;
}
+ spin_unlock(&resv->lock);
return chg;
}
vma->vm_private_data = (void *)value;
}
-struct resv_map {
- struct kref refs;
- struct list_head regions;
-};
-
-static struct resv_map *resv_map_alloc(void)
+struct resv_map *resv_map_alloc(void)
{
struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
if (!resv_map)
return NULL;
kref_init(&resv_map->refs);
+ spin_lock_init(&resv_map->lock);
INIT_LIST_HEAD(&resv_map->regions);
return resv_map;
}
-static void resv_map_release(struct kref *ref)
+void resv_map_release(struct kref *ref)
{
struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
/* Clear out any active regions before we release the map. */
- region_truncate(&resv_map->regions, 0);
+ region_truncate(resv_map, 0);
kfree(resv_map);
}
+static inline struct resv_map *inode_resv_map(struct inode *inode)
+{
+ return inode->i_mapping->private_data;
+}
+
static struct resv_map *vma_resv_map(struct vm_area_struct *vma)
{
VM_BUG_ON(!is_vm_hugetlb_page(vma));
- if (!(vma->vm_flags & VM_MAYSHARE))
+ if (vma->vm_flags & VM_MAYSHARE) {
+ struct address_space *mapping = vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+
+ return inode_resv_map(inode);
+
+ } else {
return (struct resv_map *)(get_vma_private_data(vma) &
~HPAGE_RESV_MASK);
- return NULL;
+ }
}
static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map)
goto err;
retry_cpuset:
- cpuset_mems_cookie = get_mems_allowed();
+ cpuset_mems_cookie = read_mems_allowed_begin();
zonelist = huge_zonelist(vma, address,
htlb_alloc_mask(h), &mpol, &nodemask);
}
mpol_cond_put(mpol);
- if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
+ if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
return page;
put_page(page); /* free it into the hugepage allocator */
}
-static void prep_compound_gigantic_page(struct page *page, unsigned long order)
+static void __init prep_compound_gigantic_page(struct page *page,
+ unsigned long order)
{
int i;
int nr_pages = 1 << order;
while (nr_pages--) {
if (!free_pool_huge_page(h, &node_states[N_MEMORY], 1))
break;
+ cond_resched_lock(&hugetlb_lock);
}
}
static long vma_needs_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
- struct address_space *mapping = vma->vm_file->f_mapping;
- struct inode *inode = mapping->host;
-
- if (vma->vm_flags & VM_MAYSHARE) {
- pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- return region_chg(&inode->i_mapping->private_list,
- idx, idx + 1);
+ struct resv_map *resv;
+ pgoff_t idx;
+ long chg;
- } else if (!is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
+ resv = vma_resv_map(vma);
+ if (!resv)
return 1;
- } else {
- long err;
- pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- struct resv_map *resv = vma_resv_map(vma);
+ idx = vma_hugecache_offset(h, vma, addr);
+ chg = region_chg(resv, idx, idx + 1);
- err = region_chg(&resv->regions, idx, idx + 1);
- if (err < 0)
- return err;
- return 0;
- }
+ if (vma->vm_flags & VM_MAYSHARE)
+ return chg;
+ else
+ return chg < 0 ? chg : 0;
}
static void vma_commit_reservation(struct hstate *h,
struct vm_area_struct *vma, unsigned long addr)
{
- struct address_space *mapping = vma->vm_file->f_mapping;
- struct inode *inode = mapping->host;
-
- if (vma->vm_flags & VM_MAYSHARE) {
- pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- region_add(&inode->i_mapping->private_list, idx, idx + 1);
+ struct resv_map *resv;
+ pgoff_t idx;
- } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) {
- pgoff_t idx = vma_hugecache_offset(h, vma, addr);
- struct resv_map *resv = vma_resv_map(vma);
+ resv = vma_resv_map(vma);
+ if (!resv)
+ return;
- /* Mark this page used in the map. */
- region_add(&resv->regions, idx, idx + 1);
- }
+ idx = vma_hugecache_offset(h, vma, addr);
+ region_add(resv, idx, idx + 1);
}
static struct page *alloc_huge_page(struct vm_area_struct *vma,
return 1;
}
-static void prep_compound_huge_page(struct page *page, int order)
+static void __init prep_compound_huge_page(struct page *page, int order)
{
if (unlikely(order > (MAX_ORDER - 1)))
prep_compound_gigantic_page(page, order);
while (min_count < persistent_huge_pages(h)) {
if (!free_pool_huge_page(h, nodes_allowed, 0))
break;
+ cond_resched_lock(&hugetlb_lock);
}
while (count < persistent_huge_pages(h)) {
if (!adjust_pool_surplus(h, nodes_allowed, 1))
}
kobject_put(hugepages_kobj);
+ kfree(htlb_fault_mutex_table);
}
module_exit(hugetlb_exit);
static int __init hugetlb_init(void)
{
+ int i;
+
/* Some platform decide whether they support huge pages at boot
* time. On these, such as powerpc, HPAGE_SHIFT is set to 0 when
* there is no such support
hugetlb_register_all_nodes();
hugetlb_cgroup_file_init();
+#ifdef CONFIG_SMP
+ num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus());
+#else
+ num_fault_mutexes = 1;
+#endif
+ htlb_fault_mutex_table =
+ kmalloc(sizeof(struct mutex) * num_fault_mutexes, GFP_KERNEL);
+ BUG_ON(!htlb_fault_mutex_table);
+
+ for (i = 0; i < num_fault_mutexes; i++)
+ mutex_init(&htlb_fault_mutex_table[i]);
return 0;
}
module_init(hugetlb_init);
* after this open call completes. It is therefore safe to take a
* new reference here without additional locking.
*/
- if (resv)
+ if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER))
kref_get(&resv->refs);
}
-static void resv_map_put(struct vm_area_struct *vma)
-{
- struct resv_map *resv = vma_resv_map(vma);
-
- if (!resv)
- return;
- kref_put(&resv->refs, resv_map_release);
-}
-
static void hugetlb_vm_op_close(struct vm_area_struct *vma)
{
struct hstate *h = hstate_vma(vma);
struct resv_map *resv = vma_resv_map(vma);
struct hugepage_subpool *spool = subpool_vma(vma);
- unsigned long reserve;
- unsigned long start;
- unsigned long end;
+ unsigned long reserve, start, end;
+
+ if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER))
+ return;
- if (resv) {
- start = vma_hugecache_offset(h, vma, vma->vm_start);
- end = vma_hugecache_offset(h, vma, vma->vm_end);
+ start = vma_hugecache_offset(h, vma, vma->vm_start);
+ end = vma_hugecache_offset(h, vma, vma->vm_end);
- reserve = (end - start) -
- region_count(&resv->regions, start, end);
+ reserve = (end - start) - region_count(resv, start, end);
- resv_map_put(vma);
+ kref_put(&resv->refs, resv_map_release);
- if (reserve) {
- hugetlb_acct_memory(h, -reserve);
- hugepage_subpool_put_pages(spool, reserve);
- }
+ if (reserve) {
+ hugetlb_acct_memory(h, -reserve);
+ hugepage_subpool_put_pages(spool, reserve);
}
}
BUG_ON(huge_pte_none(pte));
spin_lock(ptl);
ptep = huge_pte_offset(mm, address & huge_page_mask(h));
- if (likely(pte_same(huge_ptep_get(ptep), pte)))
+ if (likely(ptep &&
+ pte_same(huge_ptep_get(ptep), pte)))
goto retry_avoidcopy;
/*
* race occurs while re-acquiring page table
*/
spin_lock(ptl);
ptep = huge_pte_offset(mm, address & huge_page_mask(h));
- if (likely(pte_same(huge_ptep_get(ptep), pte))) {
+ if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) {
ClearPagePrivate(new_page);
/* Break COW */
}
static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep, unsigned int flags)
+ struct address_space *mapping, pgoff_t idx,
+ unsigned long address, pte_t *ptep, unsigned int flags)
{
struct hstate *h = hstate_vma(vma);
int ret = VM_FAULT_SIGBUS;
int anon_rmap = 0;
- pgoff_t idx;
unsigned long size;
struct page *page;
- struct address_space *mapping;
pte_t new_pte;
spinlock_t *ptl;
return ret;
}
- mapping = vma->vm_file->f_mapping;
- idx = vma_hugecache_offset(h, vma, address);
-
/*
* Use page lock to guard against racing truncation
* before we get page_table_lock.
if (anon_rmap) {
ClearPagePrivate(page);
hugepage_add_new_anon_rmap(page, vma, address);
- }
- else
+ } else
page_dup_rmap(page);
new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE)
&& (vma->vm_flags & VM_SHARED)));
goto out;
}
+#ifdef CONFIG_SMP
+static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
+ struct vm_area_struct *vma,
+ struct address_space *mapping,
+ pgoff_t idx, unsigned long address)
+{
+ unsigned long key[2];
+ u32 hash;
+
+ if (vma->vm_flags & VM_SHARED) {
+ key[0] = (unsigned long) mapping;
+ key[1] = idx;
+ } else {
+ key[0] = (unsigned long) mm;
+ key[1] = address >> huge_page_shift(h);
+ }
+
+ hash = jhash2((u32 *)&key, sizeof(key)/sizeof(u32), 0);
+
+ return hash & (num_fault_mutexes - 1);
+}
+#else
+/*
+ * For uniprocesor systems we always use a single mutex, so just
+ * return 0 and avoid the hashing overhead.
+ */
+static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
+ struct vm_area_struct *vma,
+ struct address_space *mapping,
+ pgoff_t idx, unsigned long address)
+{
+ return 0;
+}
+#endif
+
int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
- pte_t *ptep;
- pte_t entry;
+ pte_t *ptep, entry;
spinlock_t *ptl;
int ret;
+ u32 hash;
+ pgoff_t idx;
struct page *page = NULL;
struct page *pagecache_page = NULL;
- static DEFINE_MUTEX(hugetlb_instantiation_mutex);
struct hstate *h = hstate_vma(vma);
+ struct address_space *mapping;
address &= huge_page_mask(h);
if (!ptep)
return VM_FAULT_OOM;
+ mapping = vma->vm_file->f_mapping;
+ idx = vma_hugecache_offset(h, vma, address);
+
/*
* Serialize hugepage allocation and instantiation, so that we don't
* get spurious allocation failures if two CPUs race to instantiate
* the same page in the page cache.
*/
- mutex_lock(&hugetlb_instantiation_mutex);
+ hash = fault_mutex_hash(h, mm, vma, mapping, idx, address);
+ mutex_lock(&htlb_fault_mutex_table[hash]);
+
entry = huge_ptep_get(ptep);
if (huge_pte_none(entry)) {
- ret = hugetlb_no_page(mm, vma, address, ptep, flags);
+ ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags);
goto out_mutex;
}
put_page(page);
out_mutex:
- mutex_unlock(&hugetlb_instantiation_mutex);
-
+ mutex_unlock(&htlb_fault_mutex_table[hash]);
return ret;
}
BUG_ON(address >= end);
flush_cache_range(vma, address, end);
+ mmu_notifier_invalidate_range_start(mm, start, end);
mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex);
for (; address < end; address += huge_page_size(h)) {
spinlock_t *ptl;
*/
flush_tlb_range(vma, start, end);
mutex_unlock(&vma->vm_file->f_mapping->i_mmap_mutex);
+ mmu_notifier_invalidate_range_end(mm, start, end);
return pages << h->order;
}
long ret, chg;
struct hstate *h = hstate_inode(inode);
struct hugepage_subpool *spool = subpool_inode(inode);
+ struct resv_map *resv_map;
/*
* Only apply hugepage reservation if asked. At fault time, an
* to reserve the full area even if read-only as mprotect() may be
* called to make the mapping read-write. Assume !vma is a shm mapping
*/
- if (!vma || vma->vm_flags & VM_MAYSHARE)
- chg = region_chg(&inode->i_mapping->private_list, from, to);
- else {
- struct resv_map *resv_map = resv_map_alloc();
+ if (!vma || vma->vm_flags & VM_MAYSHARE) {
+ resv_map = inode_resv_map(inode);
+
+ chg = region_chg(resv_map, from, to);
+
+ } else {
+ resv_map = resv_map_alloc();
if (!resv_map)
return -ENOMEM;
* else has to be done for private mappings here
*/
if (!vma || vma->vm_flags & VM_MAYSHARE)
- region_add(&inode->i_mapping->private_list, from, to);
+ region_add(resv_map, from, to);
return 0;
out_err:
- if (vma)
- resv_map_put(vma);
+ if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER))
+ kref_put(&resv_map->refs, resv_map_release);
return ret;
}
void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
{
struct hstate *h = hstate_inode(inode);
- long chg = region_truncate(&inode->i_mapping->private_list, offset);
+ struct resv_map *resv_map = inode_resv_map(inode);
+ long chg = 0;
struct hugepage_subpool *spool = subpool_inode(inode);
+ if (resv_map)
+ chg = region_truncate(resv_map, offset);
spin_lock(&inode->i_lock);
inode->i_blocks -= (blocks_per_huge_page(h) * freed);
spin_unlock(&inode->i_lock);
#else /* !CONFIG_ARCH_WANT_GENERAL_HUGETLB */
/* Can be overriden by architectures */
-__attribute__((weak)) struct page *
+struct page * __weak
follow_huge_pud(struct mm_struct *mm, unsigned long address,
pud_t *pud, int write)
{
projects / cascardo / linux.git / blobdiff