Re: [PATCH 2/2][SCTP]: Convert sctp_dbg_objcnt to seq files.

[Vlad Yasevich <vladislav.yasevich@hp.com>]

Pavel Emelyanov wrote:
> This makes the code use a good proc API and the text ~50 bytes shorter.
> 
> Signed-off-by: Pavel Emelyanov <xemul@openvz.org>

Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>

> 
> ---
>  net/sctp/objcnt.c |   85 +++++++++++++++++++++++++++-------------------------
>  1 files changed, 44 insertions(+), 41 deletions(-)
> 
> diff --git a/net/sctp/objcnt.c b/net/sctp/objcnt.c
> index 2cf6ad6..2b9ac00 100644
> --- a/net/sctp/objcnt.c
> +++ b/net/sctp/objcnt.c
> @@ -80,61 +80,64 @@ static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
>  /* Callback from procfs to read out objcount information.
>   * Walk through the entries in the sctp_dbg_objcnt array, dumping
>   * the raw object counts for each monitored type.
> - *
> - * This code was modified from similar code in route.c
>   */
> -static int sctp_dbg_objcnt_read(char *buffer, char **start, off_t offset,
> -				int length, int *eof, void *data)
> +static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
>  {
> -	int len = 0;
> -	off_t pos = 0;
> -	int entries;
>  	int i;
>  	char temp[128];
>  
> -	/* How many entries? */
> -	entries = ARRAY_SIZE(sctp_dbg_objcnt);
> -
> -	/* Walk the entries and print out the debug information
> -	 * for proc fs.
> -	 */
> -	for (i = 0; i < entries; i++) {
> -		pos += 128;
> -
> -		/* Skip ahead. */
> -		if (pos <= offset) {
> -			len = 0;
> -			continue;
> -		}
> -		/* Print out each entry. */
> -		sprintf(temp, "%s: %d",
> -			sctp_dbg_objcnt[i].label,
> -			atomic_read(sctp_dbg_objcnt[i].counter));
> -
> -		sprintf(buffer + len, "%-127s\n", temp);
> -		len += 128;
> -		if (pos >= offset+length)
> -			goto done;
> -	}
> -
> -done:
> -	*start = buffer + len - (pos - offset);
> -	len = pos - offset;
> -	if (len > length)
> -		len = length;
> -
> -	return len;
> +	i = (int)*(loff_t *)v;
> +	sprintf(temp, "%s: %d", sctp_dbg_objcnt[i].label,
> +				atomic_read(sctp_dbg_objcnt[i].counter));
> +	seq_printf(seq, "%-127s\n", temp);
> +	return 0;
> +}
> +
> +static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
> +{
> +	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
> +}
> +
> +static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
> +{
> +}
> +
> +static void * sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
> +{
> +	++*pos;
> +	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
>  }
>  
> +static const struct seq_operations sctp_objcnt_seq_ops = {
> +	.start = sctp_objcnt_seq_start,
> +	.next  = sctp_objcnt_seq_next,
> +	.stop  = sctp_objcnt_seq_stop,
> +	.show  = sctp_objcnt_seq_show,
> +};
> +
> +static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
> +{
> +	return seq_open(file, &sctp_objcnt_seq_ops);
> +}
> +
> +static const struct file_operations sctp_objcnt_ops = {
> +	.open	 = sctp_objcnt_seq_open,
> +	.read	 = seq_read,
> +	.llseek	 = seq_lseek,
> +	.release = seq_release,
> +};
> +
>  /* Initialize the objcount in the proc filesystem.  */
>  void sctp_dbg_objcnt_init(void)
>  {
>  	struct proc_dir_entry *ent;
> -	ent = create_proc_read_entry("sctp_dbg_objcnt", 0, proc_net_sctp,
> -			       sctp_dbg_objcnt_read, NULL);
> +
> +	ent = create_proc_entry("sctp_dbg_objcnt", 0, proc_net_sctp);
>  	if (!ent)
>  		printk(KERN_WARNING
>  			"sctp_dbg_objcnt: Unable to create /proc entry.\n");
> +	else
> +		ent->proc_fops = &sctp_objcnt_ops;
>  }
>  
>  /* Cleanup the objcount entry in the proc filesystem.  */