Re: [PATCH] f2fs: including waf data in f2fs status information

[Chao Yu <chao@kernel.org>]

On 2023/6/2 12:48, beomsu kim wrote:
> When evaluating in f2fs, it takes much time to obtain waf data.
> This patch helps to obtain waf data without calcluation.
> 
> Signed-off-by: Beomsu Kim <beomsu7.kim@samsung.com>
> ---
>   fs/f2fs/iostat.c | 16 ++++++++++++++++
>   1 file changed, 16 insertions(+)
> 
> diff --git a/fs/f2fs/iostat.c b/fs/f2fs/iostat.c
> index 3d5bfb1ad585..6eab11b0610d 100644
> --- a/fs/f2fs/iostat.c
> +++ b/fs/f2fs/iostat.c
> @@ -34,10 +34,22 @@ int __maybe_unused iostat_info_seq_show(struct seq_file *seq, void *offset)
>   {
>          struct super_block *sb = seq->private;
>          struct f2fs_sb_info *sbi = F2FS_SB(sb);
> +       int j;
> +       unsigned long long waf = 0;
> +       unsigned long long data_written_to_storage = 0;
> +       unsigned long long data_written_by_user = 0;
>   
>          if (!sbi->iostat_enable)
>                  return 0;
>   
> +       for (j = FS_DATA_IO; j <= FS_CP_META_IO; j++)

FS_CDATA_IO is redundant?

> +               data_written_to_storage += sbi->iostat_bytes[j];
> +       for (j = FS_DATA_IO; j <= FS_CDATA_IO; j++)

Just needs to include APP_WRITE_IO and APP_MAPPED_IO?

Thanks,

> +               data_written_by_user += sbi->iostat_bytes[j];
> +
> +       if (data_written_by_user > 0)
> +               waf = data_written_to_storage * 100 / data_written_by_user;
> +
>          seq_printf(seq, "time:          %-16llu\n", ktime_get_real_seconds());
>          seq_printf(seq, "\t\t\t%-16s %-16s %-16s\n",
>                                  "io_bytes", "count", "avg_bytes");
> @@ -81,6 +93,10 @@ int __maybe_unused iostat_info_seq_show(struct seq_file *seq, void *offset)
>          IOSTAT_INFO_SHOW("fs discard", FS_DISCARD_IO);
>          IOSTAT_INFO_SHOW("fs flush", FS_FLUSH_IO);
>   
> +       /* print waf */
> +       seq_puts(seq, "[WAF]\n");
> +       seq_printf(seq, "fs waf:                %llu.%02llu\n", waf / 100, waf % 100);
> +
>          return 0;
>   }
>