Btrfs: Do more optimal file RA during shrinking and defrag

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2008-04-28 09:02:36 -04:00
parent 3bf3d9e9c2
commit 8e7bf94fd5
2 changed files with 22 additions and 9 deletions

View file

@ -2263,6 +2263,12 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
return 0;
}
static unsigned long calc_ra(unsigned long start, unsigned long last,
unsigned long nr)
{
return min(last, start + nr - 1);
}
static int noinline relocate_inode_pages(struct inode *inode, u64 start,
u64 len)
{
@ -2275,6 +2281,8 @@ static int noinline relocate_inode_pages(struct inode *inode, u64 start,
struct page *page;
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
struct file_ra_state *ra;
unsigned long total_read = 0;
unsigned long ra_pages;
ra = kzalloc(sizeof(*ra), GFP_NOFS);
@ -2282,11 +2290,17 @@ static int noinline relocate_inode_pages(struct inode *inode, u64 start,
i = start >> PAGE_CACHE_SHIFT;
last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages;
file_ra_state_init(ra, inode->i_mapping);
btrfs_force_ra(inode->i_mapping, ra, NULL, i, last_index);
kfree(ra);
for (; i <= last_index; i++) {
if (total_read % ra_pages == 0) {
btrfs_force_ra(inode->i_mapping, ra, NULL, i,
calc_ra(i, last_index, ra_pages));
}
total_read++;
page = grab_cache_page(inode->i_mapping, i);
if (!page)
goto out_unlock;

View file

@ -2814,14 +2814,12 @@ unsigned long btrfs_force_ra(struct address_space *mapping,
struct file_ra_state *ra, struct file *file,
pgoff_t offset, pgoff_t last_index)
{
pgoff_t req_size;
pgoff_t req_size = last_index - offset + 1;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
req_size = last_index - offset + 1;
offset = page_cache_readahead(mapping, ra, file, offset, req_size);
return offset;
#else
req_size = min(last_index - offset + 1, (pgoff_t)128);
page_cache_sync_readahead(mapping, ra, file, offset, req_size);
return offset + req_size;
#endif
@ -2833,7 +2831,8 @@ int btrfs_defrag_file(struct file *file) {
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
struct page *page;
unsigned long last_index;
unsigned long ra_index = 0;
unsigned long ra_pages = root->fs_info->bdi.ra_pages;
unsigned long total_read = 0;
u64 page_start;
u64 page_end;
unsigned long i;
@ -2848,11 +2847,11 @@ int btrfs_defrag_file(struct file *file) {
mutex_lock(&inode->i_mutex);
last_index = inode->i_size >> PAGE_CACHE_SHIFT;
for (i = 0; i <= last_index; i++) {
if (i == ra_index) {
ra_index = btrfs_force_ra(inode->i_mapping,
&file->f_ra,
file, ra_index, last_index);
if (total_read % ra_pages == 0) {
btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i,
min(last_index, i + ra_pages - 1));
}
total_read++;
page = grab_cache_page(inode->i_mapping, i);
if (!page)
goto out_unlock;