On 4/23/25 12:25 AM, Joanne Koong wrote:
> On Mon, Apr 21, 2025 at 7:07 PM Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx> wrote:
>>
>>
>>
>> On 4/19/25 5:06 AM, Joanne Koong wrote:
>>> Use a bitfield for tracking initialized, blocked, aborted, and io_uring
>>> state of the fuse connection. Track connected state using a bool instead
>>> of an unsigned.
>>>
>>> On a 64-bit system, this shaves off 16 bytes from the size of struct
>>> fuse_conn.
>>>
>>> No functional changes.
>>>
>>> Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
>>> ---
>>> fs/fuse/fuse_i.h | 24 ++++++++++++------------
>>> 1 file changed, 12 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
>>> index b54f4f57789f..6aecada8aadd 100644
>>> --- a/fs/fuse/fuse_i.h
>>> +++ b/fs/fuse/fuse_i.h
>>> @@ -690,24 +690,24 @@ struct fuse_conn {
>>> * active_background, bg_queue, blocked */
>>> spinlock_t bg_lock;
>>>
>>> - /** Flag indicating that INIT reply has been received. Allocating
>>> - * any fuse request will be suspended until the flag is set */
>>> - int initialized;
>>> -
>>> - /** Flag indicating if connection is blocked. This will be
>>> - the case before the INIT reply is received, and if there
>>> - are too many outstading backgrounds requests */
>>> - int blocked;
>>> -
>>> /** waitq for blocked connection */
>>> wait_queue_head_t blocked_waitq;
>>>
>>> /** Connection established, cleared on umount, connection
>>> abort and device release */
>>> - unsigned connected;
>>> + bool connected;
>>
>> Why not also convert connected to bitfield?
>
> fuse_drop_waiting() checks the connected state locklessly through
> READ_ONCE(fc->connected). The smallest size READ_ONCE supports is a
> byte, I don't think it works on bitfields.
Okay, that makes sense. Thanks.
--
Thanks,
Jingbo
