hugetlb: use mmu_gather instead of a temporary linked list for accumulating pages

Use a mmu_gather instead of a temporary linked list for accumulating pages
when we unmap a hugepage range

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Aneesh Kumar K.V 2012-07-31 16:42:03 -07:00 committed by Linus Torvalds
parent 972dc4de13
commit 24669e5847
4 changed files with 59 additions and 33 deletions

View file

@ -416,8 +416,8 @@ hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff)
else
v_offset = 0;
__unmap_hugepage_range(vma,
vma->vm_start + v_offset, vma->vm_end, NULL);
unmap_hugepage_range(vma, vma->vm_start + v_offset,
vma->vm_end, NULL);
}
}

View file

@ -7,6 +7,7 @@
struct ctl_table;
struct user_struct;
struct mmu_gather;
#ifdef CONFIG_HUGETLB_PAGE
@ -41,8 +42,9 @@ int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *,
unsigned long *, int *, int, unsigned int flags);
void unmap_hugepage_range(struct vm_area_struct *,
unsigned long, unsigned long, struct page *);
void __unmap_hugepage_range(struct vm_area_struct *,
unsigned long, unsigned long, struct page *);
void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start, unsigned long end,
struct page *ref_page);
int hugetlb_prefault(struct address_space *, struct vm_area_struct *);
void hugetlb_report_meminfo(struct seq_file *);
int hugetlb_report_node_meminfo(int, char *);
@ -98,7 +100,6 @@ static inline unsigned long hugetlb_total_pages(void)
#define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL)
#define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; })
#define hugetlb_prefault(mapping, vma) ({ BUG(); 0; })
#define unmap_hugepage_range(vma, start, end, page) BUG()
static inline void hugetlb_report_meminfo(struct seq_file *m)
{
}
@ -112,13 +113,24 @@ static inline void hugetlb_report_meminfo(struct seq_file *m)
#define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; })
#define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; })
#define huge_pte_offset(mm, address) 0
#define dequeue_hwpoisoned_huge_page(page) 0
static inline int dequeue_hwpoisoned_huge_page(struct page *page)
{
return 0;
}
static inline void copy_huge_page(struct page *dst, struct page *src)
{
}
#define hugetlb_change_protection(vma, address, end, newprot)
static inline void __unmap_hugepage_range(struct mmu_gather *tlb,
struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct page *ref_page)
{
BUG();
}
#endif /* !CONFIG_HUGETLB_PAGE */
#define HUGETLB_ANON_FILE "anon_hugepage"

View file

@ -24,8 +24,9 @@
#include <asm/page.h>
#include <asm/pgtable.h>
#include <linux/io.h>
#include <asm/tlb.h>
#include <linux/io.h>
#include <linux/hugetlb.h>
#include <linux/node.h>
#include "internal.h"
@ -2310,30 +2311,26 @@ static int is_hugetlb_entry_hwpoisoned(pte_t pte)
return 0;
}
void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct page *ref_page)
void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start, unsigned long end,
struct page *ref_page)
{
int force_flush = 0;
struct mm_struct *mm = vma->vm_mm;
unsigned long address;
pte_t *ptep;
pte_t pte;
struct page *page;
struct page *tmp;
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
/*
* A page gathering list, protected by per file i_mmap_mutex. The
* lock is used to avoid list corruption from multiple unmapping
* of the same page since we are using page->lru.
*/
LIST_HEAD(page_list);
WARN_ON(!is_vm_hugetlb_page(vma));
BUG_ON(start & ~huge_page_mask(h));
BUG_ON(end & ~huge_page_mask(h));
tlb_start_vma(tlb, vma);
mmu_notifier_invalidate_range_start(mm, start, end);
again:
spin_lock(&mm->page_table_lock);
for (address = start; address < end; address += sz) {
ptep = huge_pte_offset(mm, address);
@ -2372,30 +2369,45 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
}
pte = huge_ptep_get_and_clear(mm, address, ptep);
tlb_remove_tlb_entry(tlb, ptep, address);
if (pte_dirty(pte))
set_page_dirty(page);
list_add(&page->lru, &page_list);
page_remove_rmap(page);
force_flush = !__tlb_remove_page(tlb, page);
if (force_flush)
break;
/* Bail out after unmapping reference page if supplied */
if (ref_page)
break;
}
flush_tlb_range(vma, start, end);
spin_unlock(&mm->page_table_lock);
mmu_notifier_invalidate_range_end(mm, start, end);
list_for_each_entry_safe(page, tmp, &page_list, lru) {
page_remove_rmap(page);
list_del(&page->lru);
put_page(page);
/*
* mmu_gather ran out of room to batch pages, we break out of
* the PTE lock to avoid doing the potential expensive TLB invalidate
* and page-free while holding it.
*/
if (force_flush) {
force_flush = 0;
tlb_flush_mmu(tlb);
if (address < end && !ref_page)
goto again;
}
mmu_notifier_invalidate_range_end(mm, start, end);
tlb_end_vma(tlb, vma);
}
void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct page *ref_page)
{
mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex);
__unmap_hugepage_range(vma, start, end, ref_page);
mutex_unlock(&vma->vm_file->f_mapping->i_mmap_mutex);
struct mm_struct *mm;
struct mmu_gather tlb;
mm = vma->vm_mm;
tlb_gather_mmu(&tlb, mm, 0);
__unmap_hugepage_range(&tlb, vma, start, end, ref_page);
tlb_finish_mmu(&tlb, start, end);
}
/*
@ -2440,9 +2452,8 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
* from the time of fork. This would look like data corruption
*/
if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER))
__unmap_hugepage_range(iter_vma,
address, address + huge_page_size(h),
page);
unmap_hugepage_range(iter_vma, address,
address + huge_page_size(h), page);
}
mutex_unlock(&mapping->i_mmap_mutex);

View file

@ -1343,8 +1343,11 @@ static void unmap_single_vma(struct mmu_gather *tlb,
* Since no pte has actually been setup, it is
* safe to do nothing in this case.
*/
if (vma->vm_file)
unmap_hugepage_range(vma, start, end, NULL);
if (vma->vm_file) {
mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex);
__unmap_hugepage_range(tlb, vma, start, end, NULL);
mutex_unlock(&vma->vm_file->f_mapping->i_mmap_mutex);
}
} else
unmap_page_range(tlb, vma, start, end, details);
}