diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index f41c53328..be1090882 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -25,16 +25,15 @@ #include <asm/pgalloc.h> /* - * The swap-out functions return 1 if they successfully - * threw something out, and we got a free page. It returns - * zero if it couldn't do anything, and any other value - * indicates it decreased rss, but the page was shared. + * The swap-out function returns 1 if it successfully + * scanned all the pages it was asked to (`count'). + * It returns zero if it couldn't do anything, * - * NOTE! If it sleeps, it *must* return 1 to make sure we - * don't continue with the swap-out. Otherwise we may be - * using a process that no longer actually exists (it might - * have died while we slept). + * rss may decrease because pages are shared, but this + * doesn't count as having freed a page. */ + +/* mm->page_table_lock is held. mmap_sem is not held */ static void try_to_swap_out(struct mm_struct * mm, struct vm_area_struct* vma, unsigned long address, pte_t * page_table, struct page *page) { pte_t pte; @@ -129,6 +128,7 @@ out_unlock_restore: return; } +/* mm->page_table_lock is held. mmap_sem is not held */ static int swap_out_pmd(struct mm_struct * mm, struct vm_area_struct * vma, pmd_t *dir, unsigned long address, unsigned long end, int count) { pte_t * pte; @@ -165,6 +165,7 @@ static int swap_out_pmd(struct mm_struct * mm, struct vm_area_struct * vma, pmd_ return count; } +/* mm->page_table_lock is held. mmap_sem is not held */ static inline int swap_out_pgd(struct mm_struct * mm, struct vm_area_struct * vma, pgd_t *dir, unsigned long address, unsigned long end, int count) { pmd_t * pmd; @@ -194,6 +195,7 @@ static inline int swap_out_pgd(struct mm_struct * mm, struct vm_area_struct * vm return count; } +/* mm->page_table_lock is held. mmap_sem is not held */ static int swap_out_vma(struct mm_struct * mm, struct vm_area_struct * vma, unsigned long address, int count) { pgd_t *pgdir; @@ -218,6 +220,9 @@ static int swap_out_vma(struct mm_struct * mm, struct vm_area_struct * vma, unsi return count; } +/* + * Returns non-zero if we scanned all `count' pages + */ static int swap_out_mm(struct mm_struct * mm, int count) { unsigned long address; |