Btrfs: account for crcs in delayed ref processing
As we delete large extents, we end up doing huge amounts of COW in order
to delete the corresponding crcs. This adds accounting so that we keep
track of that space and flushing of delayed refs so that we don't build
up too much delayed crc work.
This helps limit the delayed work that must be done at commit time and
tries to avoid ENOSPC aborts because the crcs eat all the global
reserves.
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e3fe137f..cec23cf 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4197,9 +4197,10 @@
int extent_type = -1;
int ret;
int err = 0;
- int be_nice = 0;
u64 ino = btrfs_ino(inode);
u64 bytes_deleted = 0;
+ bool be_nice = 0;
+ bool should_throttle = 0;
BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
@@ -4405,19 +4406,20 @@
btrfs_header_owner(leaf),
ino, extent_offset, 0);
BUG_ON(ret);
- if (be_nice && pending_del_nr &&
- (pending_del_nr % 16 == 0) &&
- bytes_deleted > 1024 * 1024) {
+ if (btrfs_should_throttle_delayed_refs(trans, root))
btrfs_async_run_delayed_refs(root,
trans->delayed_ref_updates * 2, 0);
- }
}
if (found_type == BTRFS_INODE_ITEM_KEY)
break;
+ should_throttle =
+ btrfs_should_throttle_delayed_refs(trans, root);
+
if (path->slots[0] == 0 ||
- path->slots[0] != pending_del_slot) {
+ path->slots[0] != pending_del_slot ||
+ (be_nice && should_throttle)) {
if (pending_del_nr) {
ret = btrfs_del_items(trans, root, path,
pending_del_slot,
@@ -4430,6 +4432,15 @@
pending_del_nr = 0;
}
btrfs_release_path(path);
+ if (be_nice && should_throttle) {
+ unsigned long updates = trans->delayed_ref_updates;
+ if (updates) {
+ trans->delayed_ref_updates = 0;
+ ret = btrfs_run_delayed_refs(trans, root, updates * 2);
+ if (ret && !err)
+ err = ret;
+ }
+ }
goto search_again;
} else {
path->slots[0]--;
@@ -4449,7 +4460,7 @@
btrfs_free_path(path);
- if (be_nice && bytes_deleted > 32 * 1024 * 1024) {
+ if (be_nice && btrfs_should_throttle_delayed_refs(trans, root)) {
unsigned long updates = trans->delayed_ref_updates;
if (updates) {
trans->delayed_ref_updates = 0;