1 files changed, 11 insertions, 8 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1cae6631b3d8..ef4ce2c026d6 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3673,6 +3673,11 @@ static void force_metadata_allocation(struct btrfs_fs_info *info)
         rcu_read_unlock();
 }
 
+static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)
+{
+        return (global->size << 1);
+}
+
 static int should_alloc_chunk(struct btrfs_root *root,
                               struct btrfs_space_info *sinfo, int force)
 {
@@ -3690,7 +3695,7 @@ static int should_alloc_chunk(struct btrfs_root *root,
          * global_rsv, it doesn't change except when the transaction commits.
          */
         if (sinfo->flags & BTRFS_BLOCK_GROUP_METADATA)
-                num_allocated += global_rsv->size;
+                num_allocated += calc_global_rsv_need_space(global_rsv);
 
         /*
          * in limited mode, we want to have some free space up to
@@ -3862,7 +3867,7 @@ static int can_overcommit(struct btrfs_root *root,
 {
         struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
         u64 profile = btrfs_get_alloc_profile(root, 0);
-        u64 rsv_size = 0;
+        u64 space_size;
         u64 avail;
         u64 used;
         u64 to_add;
@@ -3870,18 +3875,16 @@ static int can_overcommit(struct btrfs_root *root,
         used = space_info->bytes_used + space_info->bytes_reserved +
                 space_info->bytes_pinned + space_info->bytes_readonly;
 
-        spin_lock(&global_rsv->lock);
-        rsv_size = global_rsv->size;
-        spin_unlock(&global_rsv->lock);
-
         /*
          * We only want to allow over committing if we have lots of actual space
          * free, but if we don't have enough space to handle the global reserve
          * space then we could end up having a real enospc problem when trying
          * to allocate a chunk or some other such important allocation.
          */
-        rsv_size <<= 1;
-        if (used + rsv_size >= space_info->total_bytes)
+        spin_lock(&global_rsv->lock);
+        space_size = calc_global_rsv_need_space(global_rsv);
+        spin_unlock(&global_rsv->lock);
+        if (used + space_size >= space_info->total_bytes)
                 return 0;
 
         used += space_info->bytes_may_use;