Re: [RFC 1/6] ath9k: add DFS statistics to debugfs

["Luis R. Rodriguez" <rodrigue@qca.qualcomm.com>]

On Mon, Oct 3, 2011 at 3:29 AM, Zefir Kurtisi <zefir.kurtisi@neratec.com> wrote:
>
> Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>
> ---
>  drivers/net/wireless/ath/ath9k/debug.c |   51 ++++++++++++++++++++++++++++++++
>  drivers/net/wireless/ath/ath9k/debug.h |   29 ++++++++++++++++++
>  2 files changed, 80 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
> index cdece82..6ad2266 100644
> --- a/drivers/net/wireless/ath/ath9k/debug.c
> +++ b/drivers/net/wireless/ath/ath9k/debug.c
> @@ -89,6 +89,53 @@ static const struct file_operations fops_debug = {
>
>  #endif
>
> +
> +#ifdef CONFIG_ATH9K_DFS

This kconfig entry doesn't exist yet, so no point in referring to it
yet, you can add a patch that adds this but describe it as work in
progress or something like that and later correct the text as you move
on.

> +
> +#define DFS_STAT(s, p) \
> +       len += snprintf(buf + len, size - len, "%28s : %10u\n", s, \
> +                       sc->debug.stats.dfs_stats.p);
> +

Either rename DFS_STAT to ATH9K_DFS_STAT or undef DFS_STAT after its usage.

> +static ssize_t read_file_dfs(struct file *file, char __user *user_buf,
> +                            size_t count, loff_t *ppos)
> +{
> +       struct ath_softc *sc = file->private_data;
> +       char *buf;
> +       unsigned int len = 0, size = 8000;
> +       ssize_t retval = 0;
> +
> +       buf = kzalloc(size, GFP_KERNEL);
> +       if (buf == NULL)
> +               return -ENOMEM;
> +
> +       DFS_STAT("DFS pulses detected     ", pulses_detected);
> +       DFS_STAT("Datalen discards        ", datalen_discards);
> +       DFS_STAT("RSSI discards           ", rssi_discards);
> +       DFS_STAT("BW info discards        ", bwinfo_discards);
> +       DFS_STAT("Primary channel pulses  ", pri_phy_errors);
> +       DFS_STAT("Secondary channel pulses", ext_phy_errors);
> +       DFS_STAT("Dual channel pulses     ", dc_phy_errors);
> +
> +       if (len > size)
> +               len = size;
> +
> +       retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
> +       kfree(buf);
> +
> +       return retval;
> +}
> +
> +
> +static const struct file_operations fops_dfs_stats = {
> +       .read = read_file_dfs,
> +       .open = ath9k_debugfs_open,
> +       .owner = THIS_MODULE,
> +       .llseek = default_llseek,
> +};
> +#endif /* CONFIG_ATH9K_DFS */

I'd prefer to keep this apart into a debugfs_dfs.c but that's just me,
I would like to ensure to keep *all* DFS stat as easy to review as
possible and am not a fan of the ifdef sprinkle.

> +
> +
>  #define DMA_BUF_LEN 1024
>
>  static ssize_t read_file_tx_chainmask(struct file *file, char __user *user_buf,
> @@ -1385,6 +1432,10 @@ int ath9k_init_debug(struct ath_hw *ah)
>        debugfs_create_u32("chanbw", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
>                           &sc->chan_bw);
>
> +#ifdef CONFIG_ATH9K_DFS
> +       debugfs_create_file("dfs_stats", S_IRUSR, sc->debug.debugfs_phy, sc,
> +                           &fops_dfs_stats);
> +#endif

If you stuff the code into a file here you'd just need a caller to
ath9k_debugfs_dfs_create() or something like that.

>        sc->debug.regidx = 0;
>        return 0;
>  }
> diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
> index 4a04510..3a3c3b7 100644
> --- a/drivers/net/wireless/ath/ath9k/debug.h
> +++ b/drivers/net/wireless/ath/ath9k/debug.h
> @@ -25,8 +25,10 @@ struct ath_buf;
>
>  #ifdef CONFIG_ATH9K_DEBUGFS
>  #define TX_STAT_INC(q, c) sc->debug.stats.txstats[q].c++
> +#define DFS_STAT_INC(sc, c) (sc->debug.stats.dfs_stats.c++)
>  #else
>  #define TX_STAT_INC(q, c) do { } while (0)
> +#define DFS_STAT_INC(sc, c) do { } while (0)

Who's using this? If no one, then why add it? That is add it only when
its in code.

>  #endif
>
>  #ifdef CONFIG_ATH9K_DEBUGFS
> @@ -171,10 +173,37 @@ struct ath_rx_stats {
>        u8 rs_antenna;
>  };
>
> +#ifdef CONFIG_ATH9K_DFS
> +/**
> + * struct ath_dfs_stats - DFS Statistics
> + *
> + * @pulses_detected: No. of pulses detected so far
> + * @datalen_discards:  No. of pulses discarded due to invalid datalen
> + * @rssi_discards: No. of pulses discarded due to invalid RSSI
> + * @bwinfo_discards: No. of pulses discarded due to invalid BW info
> + * @pri_phy_errors: No. of pulses reported for primary channel
> + * @ext_phy_errors: No. of pulses reported for extension channel
> + * @dc_phy_errors: No. of pulses reported for primary + extension channel
> + */
> +struct ath_dfs_stats {
> +       u32 pulses_detected;
> +       u32 datalen_discards;
> +       u32 rssi_discards;
> +       u32 bwinfo_discards;
> +       u32 pri_phy_errors;
> +       u32 ext_phy_errors;
> +       u32 dc_phy_errors;
> +};
> +#endif
> +
> +
>  struct ath_stats {
>        struct ath_interrupt_stats istats;
>        struct ath_tx_stats txstats[ATH9K_NUM_TX_QUEUES];
>        struct ath_rx_stats rxstats;
> +#ifdef CONFIG_ATH9K_DFS
> +       struct ath_dfs_stats dfs_stats;
> +#endif

If code used this set of stats this would give a compile error if
CONFIG_ATH9K_DEBUGFS is enabled but CONFIG_ATH9K_DFS was disabled as
the ifdef over the increment stat stuff is over CONFIG_ATH9K_DEBUGFS
and not CONFIG_ATH9K_DFS, but again, no one uses this code yet.

  Luis