On Wed, Feb 26, 2014 at 10:25:24AM +0800, Wang Shilong wrote:

On 02/26/2014 12:28 AM, David Sterba wrote:

quoted

On Tue, Feb 25, 2014 at 07:48:57PM +0800, Wang Shilong wrote:

quoted

Signed-off-by: Wang Shilong <redacted>
---
 ctree.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/ctree.h b/ctree.h
index 3cc3477..9b461af 100644
--- a/ctree.h
+++ b/ctree.h

@@ -984,9 +984,11 @@ struct btrfs_fs_info {
 	struct btrfs_fs_devices *fs_devices;
 	struct list_head space_info;
 	int system_allocs;
-	int readonly;
-	int on_restoring;
-	int is_chunk_recover;
+
+	unsigned int readonly:1;
+	unsigned int on_restoring:1;
+	unsigned int is_chunk_recover:1;

Well, the integers are wasteful, but there's only one instance of
fs_info per fsck run, so it saves like 8 bytes in total. I'm not sure
this patch is needed.

Originally, i wrote this patch, it is because i was going to add a new flag.
However, that approach has been replaced by a better idea.

Anyway, this patch will be a good start, however, i don't insist on it.
We can also change it  when we have to add another flag later.

Ok, let's keep it, as an example of the pattern 'bitfields for flags'.