summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorChris Mason <chris.mason@oracle.com>2010-10-26 13:40:45 -0400
committerChris Mason <chris.mason@oracle.com>2010-10-29 11:25:36 -0400
commitbf9022e06af553553bc8f4e21ce36147ca6eae68 (patch)
treee33d9a25fc5ec8e03c1f0d5a4775c865e0520811 /fs
parente5bc2458293b2af6c0b94435965c68cc70974b56 (diff)
Btrfs: use the flusher threads for delalloc throttling
We have a fairly complex set of loops around walking our list of delalloc inodes when we find metadata delalloc space running low. It doesn't work very well, can use large amounts of CPU and doesn't do very efficient writeback. This switches us to kick the bdi flusher threads instead. All dirty data in btrfs is accounted as delalloc data, so this is very similar in terms of what it writes, but we're able to just kick off the IO and wait for progress. Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/btrfs/extent-tree.c33
1 files changed, 15 insertions, 18 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 980d6a3c342c..59c8daaacf0c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3328,15 +3328,14 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
u64 reserved;
u64 max_reclaim;
u64 reclaimed = 0;
- int no_reclaim = 0;
int pause = 1;
- int ret;
+ int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
block_rsv = &root->fs_info->delalloc_block_rsv;
space_info = block_rsv->space_info;
- spin_lock(&space_info->lock);
+
+ smp_mb();
reserved = space_info->bytes_reserved;
- spin_unlock(&space_info->lock);
if (reserved == 0)
return 0;
@@ -3344,20 +3343,11 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
max_reclaim = min(reserved, to_reclaim);
while (1) {
- ret = btrfs_start_one_delalloc_inode(root, trans ? 1 : 0, sync);
- if (!ret) {
- if (no_reclaim > 2)
- break;
- no_reclaim++;
- __set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(pause);
- pause <<= 1;
- if (pause > HZ / 10)
- pause = HZ / 10;
- } else {
- no_reclaim = 0;
- pause = 1;
- }
+ /* have the flusher threads jump in and do some IO */
+ smp_mb();
+ nr_pages = min_t(unsigned long, nr_pages,
+ root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
+ writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
spin_lock(&space_info->lock);
if (reserved > space_info->bytes_reserved)
@@ -3370,6 +3360,13 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
if (trans && trans->transaction->blocked)
return -EAGAIN;
+
+ __set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(pause);
+ pause <<= 1;
+ if (pause > HZ / 10)
+ pause = HZ / 10;
+
}
return reclaimed >= to_reclaim;
}