In shrink_delalloc(), if can_overcommit() returns true, shrink_delalloc()
will give up shrinking delalloc bytes, in this case we should check whether
some tickcts' requests can overcommit, if some can, we can satisfy them
timely and directly.
Signed-off-by: Wang Xiaoguang
---
fs/btrfs/extent-tree.c | 43 +++
1 file changed, 43 insertions(+)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 661f039..c2e6871 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4971,6 +4971,47 @@ static void wake_all_tickets(struct list_head *head)
}
/*
+ * This function must be protected by btrfs_space_info's lock.
+ * In shrink_delalloc(), if can_overcommit() returns true, shrink_delalloc()
+ * will not shrink delalloc bytes any more, in this case we should check
+ * whether some tickcts' requests can overcommit, if some can, we can satisfy
+ * them timely and directly.
+ */
+static void try_to_wake_tickets(struct btrfs_root *root,
+ struct btrfs_space_info *space_info)
+{
+ struct reserve_ticket *ticket;
+ struct list_head *head = &space_info->priority_tickets;
+ enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
+ u64 used;
+
+again:
+ while (!list_empty(head)) {
+ ticket = list_first_entry(head, struct reserve_ticket,
+ list);
+ used = space_info->bytes_used +
+ space_info->bytes_reserved + space_info->bytes_pinned +
+ space_info->bytes_readonly + space_info->bytes_may_use;
+
+ if (used + ticket->bytes <= space_info->total_bytes ||
+ can_overcommit(root, space_info, ticket->bytes, flush)) {
+ space_info->bytes_may_use += ticket->bytes;
+ list_del_init(&ticket->list);
+ ticket->bytes = 0;
+ space_info->tickets_id++;
+ wake_up(&ticket->wait);
+ } else
+ return;
+ }
+
+ if (head == &space_info->priority_tickets) {
+ head = &space_info->tickets;
+ flush = BTRFS_RESERVE_FLUSH_ALL;
+ goto again;
+ }
+}
+
+/*
* This is for normal flushers, we can wait all goddamned day if we want to.
We
* will loop and continuously try to flush as long as we are making progress.
* We count progress as clearing off tickets each time we have to loop.
@@ -5006,6 +5047,8 @@ static void btrfs_async_reclaim_metadata_space(struct
work_struct *work)
ret = flush_space(fs_info->fs_root, space_info, to_reclaim,
flush_state, reclaim_priority);
spin_lock(&space_info->lock);
+ if (!ret)
+ try_to_wake_tickets(fs_info->fs_root, space_info);
if (list_empty(&space_info->tickets)) {
space_info->flush = 0;
spin_unlock(&space_info->lock);
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
