btrfs: mark extent buffer alignment checks as unlikely

We are not expecting to ever fail the extent buffer alignment checks, so
mark them as unlikely to allow the compiler to potentially generate more
optimized code.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 681f4f2e44197a04ef8bab1b1574a7049235e676..5f0cce1bb7c6f846a4f9901b510474e7ef1d8ea7 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3228,25 +3228,25 @@ static bool check_eb_alignment(struct btrfs_fs_info *fs_info, u64 start)
 {
        const u32 nodesize = fs_info->nodesize;
 
-       if (!IS_ALIGNED(start, fs_info->sectorsize)) {
+       if (unlikely(!IS_ALIGNED(start, fs_info->sectorsize))) {
                btrfs_err(fs_info, "bad tree block start %llu", start);
                return true;
        }
 
-       if (nodesize < PAGE_SIZE && !IS_ALIGNED(start, nodesize)) {
+       if (unlikely(nodesize < PAGE_SIZE && !IS_ALIGNED(start, nodesize))) {
                btrfs_err(fs_info,
                "tree block is not nodesize aligned, start %llu nodesize %u",
                          start, nodesize);
                return true;
        }
-       if (nodesize >= PAGE_SIZE && !PAGE_ALIGNED(start)) {
+       if (unlikely(nodesize >= PAGE_SIZE && !PAGE_ALIGNED(start))) {
                btrfs_err(fs_info,
                "tree block is not page aligned, start %llu nodesize %u",
                          start, nodesize);
                return true;
        }
-       if (!IS_ALIGNED(start, nodesize) &&
-           !test_and_set_bit(BTRFS_FS_UNALIGNED_TREE_BLOCK, &fs_info->flags)) {
+       if (unlikely(!IS_ALIGNED(start, nodesize) &&
+                    !test_and_set_bit(BTRFS_FS_UNALIGNED_TREE_BLOCK, &fs_info->flags))) {
                btrfs_warn(fs_info,
 "tree block not nodesize aligned, start %llu nodesize %u, can be resolved by a full metadata balance",
                              start, nodesize);