diff mbox series

[v2,1/2] ocfs2: dlmfs: not clear USER_LOCK_ATTACHED when destroy lock

Message ID 20220518235224.87100-1-junxiao.bi@oracle.com (mailing list archive)
State New
Headers show
Series [v2,1/2] ocfs2: dlmfs: not clear USER_LOCK_ATTACHED when destroy lock | expand

Commit Message

Junxiao Bi May 18, 2022, 11:52 p.m. UTC
The following function is the only place that check USER_LOCK_ATTACHED,
this flag is set when lock request is granted through user_ast() and
only the following function will clear it.

Checking of this flag here is to make sure ocfs2_dlm_unlock is not
issued if this lock is never granted. For example, lock file is created
and then get removed, open file never happens.

Clearing the flag here is not necessary because this is the only function
that checks it, if another flow is executing user_dlm_destroy_lock(), it
will bail out at the beginning because of USER_LOCK_IN_TEARDOWN and never
check USER_LOCK_ATTACHED.
Drop the clear, so we don't need take care it for the following
error handling patch.

int user_dlm_destroy_lock(struct user_lock_res *lockres)
{
    ...

    status = 0;
    if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
        spin_unlock(&lockres->l_lock);
        goto bail;
    }

    lockres->l_flags &= ~USER_LOCK_ATTACHED;
    lockres->l_flags |= USER_LOCK_BUSY;
    spin_unlock(&lockres->l_lock);

	status = ocfs2_dlm_unlock(conn, &lockres->l_lksb, DLM_LKF_VALBLK);
    if (status) {
        user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
        goto bail;
    }
	...
}

V1 discussion with Joseph:
https://lore.kernel.org/all/7b620c53-0c45-da2c-829e-26195cbe7d4e@linux.alibaba.com/T/

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
---
 fs/ocfs2/dlmfs/userdlm.c | 1 -
 1 file changed, 1 deletion(-)

Comments

Joseph Qi May 19, 2022, 1:59 a.m. UTC | #1
On 5/19/22 7:52 AM, Junxiao Bi wrote:
> The following function is the only place that check USER_LOCK_ATTACHED,
> this flag is set when lock request is granted through user_ast() and
> only the following function will clear it.
> 
> Checking of this flag here is to make sure ocfs2_dlm_unlock is not
> issued if this lock is never granted. For example, lock file is created
> and then get removed, open file never happens.
> 
> Clearing the flag here is not necessary because this is the only function
> that checks it, if another flow is executing user_dlm_destroy_lock(), it
> will bail out at the beginning because of USER_LOCK_IN_TEARDOWN and never
> check USER_LOCK_ATTACHED.
> Drop the clear, so we don't need take care it for the following
> error handling patch.
> 
> int user_dlm_destroy_lock(struct user_lock_res *lockres)
> {
>     ...
> 
>     status = 0;
>     if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
>         spin_unlock(&lockres->l_lock);
>         goto bail;
>     }
> 
>     lockres->l_flags &= ~USER_LOCK_ATTACHED;
>     lockres->l_flags |= USER_LOCK_BUSY;
>     spin_unlock(&lockres->l_lock);
> 
> 	status = ocfs2_dlm_unlock(conn, &lockres->l_lksb, DLM_LKF_VALBLK);
>     if (status) {
>         user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
>         goto bail;
>     }
> 	...
> }
> 
> V1 discussion with Joseph:
> https://lore.kernel.org/all/7b620c53-0c45-da2c-829e-26195cbe7d4e@linux.alibaba.com/T/
> 
> Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>

Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
> ---
>  fs/ocfs2/dlmfs/userdlm.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/fs/ocfs2/dlmfs/userdlm.c b/fs/ocfs2/dlmfs/userdlm.c
> index 29f183a15798..af0be612589c 100644
> --- a/fs/ocfs2/dlmfs/userdlm.c
> +++ b/fs/ocfs2/dlmfs/userdlm.c
> @@ -619,7 +619,6 @@ int user_dlm_destroy_lock(struct user_lock_res *lockres)
>  		goto bail;
>  	}
>  
> -	lockres->l_flags &= ~USER_LOCK_ATTACHED;
>  	lockres->l_flags |= USER_LOCK_BUSY;
>  	spin_unlock(&lockres->l_lock);
>
diff mbox series

Patch

diff --git a/fs/ocfs2/dlmfs/userdlm.c b/fs/ocfs2/dlmfs/userdlm.c
index 29f183a15798..af0be612589c 100644
--- a/fs/ocfs2/dlmfs/userdlm.c
+++ b/fs/ocfs2/dlmfs/userdlm.c
@@ -619,7 +619,6 @@  int user_dlm_destroy_lock(struct user_lock_res *lockres)
 		goto bail;
 	}
 
-	lockres->l_flags &= ~USER_LOCK_ATTACHED;
 	lockres->l_flags |= USER_LOCK_BUSY;
 	spin_unlock(&lockres->l_lock);