diff options
| -rw-r--r-- | include/linux/swap.h | 19 | ||||
| -rw-r--r-- | mm/memory.c | 45 | ||||
| -rw-r--r-- | mm/shmem.c | 6 | ||||
| -rw-r--r-- | mm/swap_state.c | 47 |
4 files changed, 57 insertions, 60 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index 4f3838adbb3..9fa1aef1b82 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -158,9 +158,6 @@ struct swap_list_t { /* Swap 50% full? Release swapcache more aggressively.. */ #define vm_swap_full() (nr_swap_pages*2 < total_swap_pages) -/* linux/mm/memory.c */ -extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct *); - /* linux/mm/page_alloc.c */ extern unsigned long totalram_pages; extern unsigned long totalreserve_pages; @@ -230,9 +227,12 @@ extern int move_from_swap_cache(struct page *, unsigned long, struct address_space *); extern void free_page_and_swap_cache(struct page *); extern void free_pages_and_swap_cache(struct page **, int); -extern struct page * lookup_swap_cache(swp_entry_t); -extern struct page * read_swap_cache_async(swp_entry_t, struct vm_area_struct *vma, - unsigned long addr); +extern struct page *lookup_swap_cache(swp_entry_t); +extern struct page *read_swap_cache_async(swp_entry_t, + struct vm_area_struct *vma, unsigned long addr); +extern struct page *swapin_readahead(swp_entry_t, + struct vm_area_struct *vma, unsigned long addr); + /* linux/mm/swapfile.c */ extern long total_swap_pages; extern unsigned int nr_swapfiles; @@ -306,7 +306,7 @@ static inline void swap_free(swp_entry_t swp) { } -static inline struct page *read_swap_cache_async(swp_entry_t swp, +static inline struct page *swapin_readahead(swp_entry_t swp, struct vm_area_struct *vma, unsigned long addr) { return NULL; @@ -317,11 +317,6 @@ static inline struct page *lookup_swap_cache(swp_entry_t swp) return NULL; } -static inline int valid_swaphandles(swp_entry_t entry, unsigned long *offset) -{ - return 0; -} - #define can_share_swap_page(p) (page_mapcount(p) == 1) static inline int move_to_swap_cache(struct page *page, swp_entry_t entry) diff --git a/mm/memory.c b/mm/memory.c index 1d803c2d018..ccc9403d535 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1980,48 +1980,6 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end) return 0; } -/** - * swapin_readahead - swap in pages in hope we need them soon - * @entry: swap entry of this memory - * @addr: address to start - * @vma: user vma this addresses belong to - * - * Primitive swap readahead code. We simply read an aligned block of - * (1 << page_cluster) entries in the swap area. This method is chosen - * 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 down_read on the vma->vm_mm if vma is not NULL. - */ -void swapin_readahead(swp_entry_t entry, unsigned long addr,struct vm_area_struct *vma) -{ - int nr_pages; - struct page *page; - unsigned long offset; - unsigned long end_offset; - - /* - * Get starting offset for readaround, and number of pages to read. - * Adjust starting address by readbehind (for NUMA interleave case)? - * No, it's very unlikely that swap layout would follow vma layout, - * more likely that neighbouring swap pages came from the same node: - * so use the same "addr" to choose the same node for each swap read. - */ - nr_pages = valid_swaphandles(entry, &offset); - for (end_offset = offset + nr_pages; offset < end_offset; offset++) { - /* Ok, do the async read-ahead now */ - page = read_swap_cache_async(swp_entry(swp_type(entry), offset), - vma, addr); - if (!page) - break; - page_cache_release(page); - } - lru_add_drain(); /* Push any new pages onto the LRU now */ -} - /* * We enter with non-exclusive mmap_sem (to exclude vma changes, * but allow concurrent faults), and pte mapped but not yet locked. @@ -2049,8 +2007,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, page = lookup_swap_cache(entry); if (!page) { grab_swap_token(); /* Contend for token _before_ read-in */ - swapin_readahead(entry, address, vma); - page = read_swap_cache_async(entry, vma, address); + page = swapin_readahead(entry, vma, address); if (!page) { /* * Back out if somebody else faulted in this pte diff --git a/mm/shmem.c b/mm/shmem.c index 88c6685f16b..3a22a8f7933 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1036,8 +1036,7 @@ static struct page *shmem_swapin(struct shmem_inode_info *info, pvma.vm_pgoff = idx; pvma.vm_ops = NULL; pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx); - swapin_readahead(entry, 0, &pvma); - page = read_swap_cache_async(entry, &pvma, 0); + page = swapin_readahead(entry, &pvma, 0); mpol_free(pvma.vm_policy); return page; } @@ -1067,8 +1066,7 @@ static inline int shmem_parse_mpol(char *value, int *policy, static inline struct page * shmem_swapin(struct shmem_inode_info *info,swp_entry_t entry,unsigned long idx) { - swapin_readahead(entry, 0, NULL); - return read_swap_cache_async(entry, NULL, 0); + return swapin_readahead(entry, NULL, 0); } static inline struct page * diff --git a/mm/swap_state.c b/mm/swap_state.c index b52635601df..668a8042263 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -10,6 +10,7 @@ #include <linux/mm.h> #include <linux/kernel_stat.h> #include <linux/swap.h> +#include <linux/swapops.h> #include <linux/init.h> #include <linux/pagemap.h> #include <linux/buffer_head.h> @@ -368,3 +369,49 @@ struct page *read_swap_cache_async(swp_entry_t entry, page_cache_release(new_page); return found_page; } + +/** + * swapin_readahead - swap in pages in hope we need them soon + * @entry: swap entry of this memory + * @vma: user vma this address belongs to + * @addr: target address for mempolicy + * + * Returns the struct page for entry and addr, after queueing swapin. + * + * Primitive swap readahead code. We simply read an aligned block of + * (1 << page_cluster) entries in the swap area. This method is chosen + * 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 down_read on the vma->vm_mm if vma is not NULL. + */ +struct page *swapin_readahead(swp_entry_t entry, + struct vm_area_struct *vma, unsigned long addr) +{ + int nr_pages; + struct page *page; + unsigned long offset; + unsigned long end_offset; + + /* + * Get starting offset for readaround, and number of pages to read. + * Adjust starting address by readbehind (for NUMA interleave case)? + * No, it's very unlikely that swap layout would follow vma layout, + * more likely that neighbouring swap pages came from the same node: + * so use the same "addr" to choose the same node for each swap read. + */ + nr_pages = valid_swaphandles(entry, &offset); + for (end_offset = offset + nr_pages; offset < end_offset; offset++) { + /* Ok, do the async read-ahead now */ + page = read_swap_cache_async(swp_entry(swp_type(entry), offset), + vma, addr); + if (!page) + break; + page_cache_release(page); + } + lru_add_drain(); /* Push any new pages onto the LRU now */ + return read_swap_cache_async(entry, vma, addr); +} |