Re: [PATCH] ocfs2: add last unlock times in locking_state

[Joseph Qi]

Hi Gang,

On 19/4/25 17:12, Gang He wrote:
> ocfs2 file system uses locking_state file under debugfs to dump
> each ocfs2 file system's dlm lock resources, but the dlm lock
> resources in memory are becoming more and more after the files
> were touched by the user. it will become a bit difficult to analyze
> these dlm lock resource records in locking_state file by the upper
> scripts, though some files are not active for now, which were
> accessed long time ago.
> Then, I'd like to add last pr/ex unlock times in locking_state file
> for each dlm lock resource record, the the upper scripts can use
> last unlock time to filter inactive dlm lock resource record.
> 
> Signed-off-by: Gang He <ghe@xxxxxxxx>
> ---
>  fs/ocfs2/dlmglue.c | 21 +++++++++++++++++----
>  fs/ocfs2/ocfs2.h   |  1 +
>  2 files changed, 18 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
> index af405586c5b1..dccf4136f8c1 100644
> --- a/fs/ocfs2/dlmglue.c
> +++ b/fs/ocfs2/dlmglue.c
> @@ -448,7 +448,7 @@ static void ocfs2_update_lock_stats(struct ocfs2_lock_res *res, int level,
>  				    struct ocfs2_mask_waiter *mw, int ret)
>  {
>  	u32 usec;
> -	ktime_t kt;
> +	ktime_t last, kt;
>  	struct ocfs2_lock_stats *stats;
>  
>  	if (level == LKM_PRMODE)
> @@ -458,7 +458,8 @@ static void ocfs2_update_lock_stats(struct ocfs2_lock_res *res, int level,
>  	else
>  		return;
>  
> -	kt = ktime_sub(ktime_get(), mw->mw_lock_start);
> +	last = ktime_get();
> +	kt = ktime_sub(last, mw->mw_lock_start);
>  	usec = ktime_to_us(kt);
>  
>  	stats->ls_gets++;
> @@ -474,6 +475,8 @@ static void ocfs2_update_lock_stats(struct ocfs2_lock_res *res, int level,
>  
>  	if (ret)
>  		stats->ls_fail++;
> +
> +	stats->ls_last = ktime_to_timespec(last).tv_sec;
>  }
>  
>  static inline void ocfs2_track_lock_refresh(struct ocfs2_lock_res *lockres)
> @@ -3093,8 +3096,10 @@ static void *ocfs2_dlm_seq_next(struct seq_file *m, void *v, loff_t *pos)
>   *	- Lock stats printed
>   * New in version 3
>   *	- Max time in lock stats is in usecs (instead of nsecs)
> + * New in version 4
> + *	- Add last pr/ex unlock times in secs

Why not usecs?
BTW, should we change tools side like debugfs as well?

Thanks,
Joseph

>   */
> -#define OCFS2_DLM_DEBUG_STR_VERSION 3
> +#define OCFS2_DLM_DEBUG_STR_VERSION 4
>  static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
>  {
>  	int i;
> @@ -3145,6 +3150,8 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
>  # define lock_max_prmode(_l)		((_l)->l_lock_prmode.ls_max)
>  # define lock_max_exmode(_l)		((_l)->l_lock_exmode.ls_max)
>  # define lock_refresh(_l)		((_l)->l_lock_refresh)
> +# define lock_last_prmode(_l)		((_l)->l_lock_prmode.ls_last)
> +# define lock_last_exmode(_l)		((_l)->l_lock_exmode.ls_last)
>  #else
>  # define lock_num_prmode(_l)		(0)
>  # define lock_num_exmode(_l)		(0)
> @@ -3155,6 +3162,8 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
>  # define lock_max_prmode(_l)		(0)
>  # define lock_max_exmode(_l)		(0)
>  # define lock_refresh(_l)		(0)
> +# define lock_last_prmode(_l)		(0)
> +# define lock_last_exmode(_l)		(0)
>  #endif
>  	/* The following seq_print was added in version 2 of this output */
>  	seq_printf(m, "%u\t"
> @@ -3165,6 +3174,8 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
>  		   "%llu\t"
>  		   "%u\t"
>  		   "%u\t"
> +		   "%u\t"
> +		   "%u\t"
>  		   "%u\t",
>  		   lock_num_prmode(lockres),
>  		   lock_num_exmode(lockres),
> @@ -3174,7 +3185,9 @@ static int ocfs2_dlm_seq_show(struct seq_file *m, void *v)
>  		   lock_total_exmode(lockres),
>  		   lock_max_prmode(lockres),
>  		   lock_max_exmode(lockres),
> -		   lock_refresh(lockres));
> +		   lock_refresh(lockres),
> +		   lock_last_prmode(lockres),
> +		   lock_last_exmode(lockres));
>  
>  	/* End the line */
>  	seq_printf(m, "\n");
> diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
> index 1f029fbe8b8d..8efa022684f4 100644
> --- a/fs/ocfs2/ocfs2.h
> +++ b/fs/ocfs2/ocfs2.h
> @@ -164,6 +164,7 @@ struct ocfs2_lock_stats {
>  
>  	/* Storing max wait in usecs saves 24 bytes per inode */
>  	u32		ls_max;		/* Max wait in USEC */
> +	u32		ls_last;	/* Last unlock time in SEC */
>  };
>  #endif
>  
>