btrfs: state information for readahead

Add state information for readahead to btrfs_fs_info and btrfs_device

Changes v2:
 - don't wait in radix_trees
 - add own set of workers for readahead

Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Arne Jansen <sensille@gmx.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1220d04072c8..fd28c40e9ec3 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1711,6 +1711,10 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         fs_info->defrag_inodes = RB_ROOT;
         fs_info->trans_no_join = 0;
 
+        /* readahead state */
+        INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
+        spin_lock_init(&fs_info->reada_lock);
+
         fs_info->thread_pool_size = min_t(unsigned long,
                                           num_online_cpus() + 2, 8);
 
@@ -1903,6 +1907,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
                            fs_info->thread_pool_size,
                            &fs_info->generic_worker);
+        btrfs_init_workers(&fs_info->readahead_workers, "readahead",
+                           fs_info->thread_pool_size,
+                           &fs_info->generic_worker);
 
         /*
          * endios are largely parallel and should have a very
@@ -1913,6 +1920,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
         fs_info->endio_write_workers.idle_thresh = 2;
         fs_info->endio_meta_write_workers.idle_thresh = 2;
+        fs_info->readahead_workers.idle_thresh = 2;
 
         btrfs_start_workers(&fs_info->workers, 1);
         btrfs_start_workers(&fs_info->generic_worker, 1);
@@ -1926,6 +1934,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         btrfs_start_workers(&fs_info->endio_freespace_worker, 1);
         btrfs_start_workers(&fs_info->delayed_workers, 1);
         btrfs_start_workers(&fs_info->caching_workers, 1);
+        btrfs_start_workers(&fs_info->readahead_workers, 1);
 
         fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
         fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
@@ -2650,6 +2659,7 @@ int close_ctree(struct btrfs_root *root)
         btrfs_stop_workers(&fs_info->submit_workers);
         btrfs_stop_workers(&fs_info->delayed_workers);
         btrfs_stop_workers(&fs_info->caching_workers);
+        btrfs_stop_workers(&fs_info->readahead_workers);
 
         btrfs_close_devices(fs_info->fs_devices);
         btrfs_mapping_tree_free(&fs_info->mapping_tree);