diff options
| -rw-r--r-- | include/linux/mm.h | 5 | ||||
| -rw-r--r-- | mm/filemap.c | 12 | ||||
| -rw-r--r-- | mm/readahead.c | 23 |
3 files changed, 12 insertions, 28 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index ad613ed66ab..33da7f53884 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1178,8 +1178,6 @@ void task_dirty_inc(struct task_struct *tsk); #define VM_MAX_READAHEAD 128 /* kbytes */ #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ -int do_page_cache_readahead(struct address_space *mapping, struct file *filp, - pgoff_t offset, unsigned long nr_to_read); int force_page_cache_readahead(struct address_space *mapping, struct file *filp, pgoff_t offset, unsigned long nr_to_read); @@ -1197,6 +1195,9 @@ void page_cache_async_readahead(struct address_space *mapping, unsigned long size); unsigned long max_sane_readahead(unsigned long nr); +unsigned long ra_submit(struct file_ra_state *ra, + struct address_space *mapping, + struct file *filp); /* Do stack extension */ extern int expand_stack(struct vm_area_struct *vma, unsigned long address); diff --git a/mm/filemap.c b/mm/filemap.c index 5c0c6518f34..734891d0663 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1488,13 +1488,15 @@ static void do_sync_mmap_readahead(struct vm_area_struct *vma, if (ra->mmap_miss > MMAP_LOTSAMISS) return; + /* + * mmap read-around + */ ra_pages = max_sane_readahead(ra->ra_pages); if (ra_pages) { - pgoff_t start = 0; - - if (offset > ra_pages / 2) - start = offset - ra_pages / 2; - do_page_cache_readahead(mapping, file, start, ra_pages); + ra->start = max_t(long, 0, offset - ra_pages/2); + ra->size = ra_pages; + ra->async_size = 0; + ra_submit(ra, mapping, file); } } diff --git a/mm/readahead.c b/mm/readahead.c index d7c6e143a12..a7f01fcce9e 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -133,15 +133,12 @@ out: } /* - * do_page_cache_readahead actually reads a chunk of disk. It allocates all + * __do_page_cache_readahead() actually reads a chunk of disk. It allocates all * the pages first, then submits them all for I/O. This avoids the very bad * behaviour which would occur if page allocations are causing VM writeback. * We really don't want to intermingle reads and writes like that. * * Returns the number of pages requested, or the maximum amount of I/O allowed. - * - * do_page_cache_readahead() returns -1 if it encountered request queue - * congestion. */ static int __do_page_cache_readahead(struct address_space *mapping, struct file *filp, @@ -232,22 +229,6 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp, } /* - * This version skips the IO if the queue is read-congested, and will tell the - * block layer to abandon the readahead if request allocation would block. - * - * force_page_cache_readahead() will ignore queue congestion and will block on - * request queues. - */ -int do_page_cache_readahead(struct address_space *mapping, struct file *filp, - pgoff_t offset, unsigned long nr_to_read) -{ - if (bdi_read_congested(mapping->backing_dev_info)) - return -1; - - return __do_page_cache_readahead(mapping, filp, offset, nr_to_read, 0); -} - -/* * Given a desired number of PAGE_CACHE_SIZE readahead pages, return a * sensible upper limit. */ @@ -260,7 +241,7 @@ unsigned long max_sane_readahead(unsigned long nr) /* * Submit IO for the read-ahead request in file_ra_state. */ -static unsigned long ra_submit(struct file_ra_state *ra, +unsigned long ra_submit(struct file_ra_state *ra, struct address_space *mapping, struct file *filp) { int actual; |