linux-kernel - Re: [PATCH v2] x86/intel_telemetry: Add debugfs entry for S0ix residency

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Date:   Fri, 30 Jun 2017 19:18:22 +0300
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Rajneesh Bhardwaj <rajneesh.bhardwaj@...el.com>
Cc:     Platform Driver <platform-driver-x86@...r.kernel.org>,
        "dvhart@...radead.org" <dvhart@...radead.org>,
        Andy Shevchenko <andy@...radead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Shanth Murthy <shanth.murthy@...el.com>,
        Souvik Kumar Chakravarty <souvik.k.chakravarty@...el.com>
Subject: Re: [PATCH v2] x86/intel_telemetry: Add debugfs entry for S0ix residency

On Fri, Jun 23, 2017 at 7:52 PM, Rajneesh Bhardwaj
<rajneesh.bhardwaj@...el.com> wrote:
> This adds a debugfs consumer for the exported kernel API
> intel_pmc_read_s0ix_residency. This debugfs entry reads S0ix residency
> directly from the PMC hardware counters.

Applied for testing, thanks!

>
> TEST:
> - echo freeze > /sys/power/state
> - Wake the system, read the S0ix residency i.e.
>   cat /sys/kernel/debug/telemetry/s0ix_residency_usec
>
> Signed-off-by: Shanth Murthy <shanth.murthy@...el.com>
> Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@...el.com>
> ---
> Changes in v2:
>  * Fixed typo in pr_err :- Changed s0ix_residency_us to s0ix_residency_usec
>  * Minor change w.r.t s0ix_total_res variable declaration
>
>  drivers/platform/x86/intel_telemetry_debugfs.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>
> diff --git a/drivers/platform/x86/intel_telemetry_debugfs.c b/drivers/platform/x86/intel_telemetry_debugfs.c
> index efc0140..a4267b8 100644
> --- a/drivers/platform/x86/intel_telemetry_debugfs.c
> +++ b/drivers/platform/x86/intel_telemetry_debugfs.c
> @@ -713,6 +713,24 @@ static int telem_soc_state_open(struct inode *inode, struct file *file)
>         .release        = single_release,
>  };
>
> +static int telem_s0ix_res_get(void *data, u64 *val)
> +{
> +       u64 s0ix_total_res;
> +       int ret;
> +
> +       ret = intel_pmc_s0ix_counter_read(&s0ix_total_res);
> +       if (ret) {
> +               pr_err("Failed to read S0ix residency");
> +               return ret;
> +       }
> +
> +       *val = s0ix_total_res;
> +
> +       return 0;
> +}
> +
> +DEFINE_DEBUGFS_ATTRIBUTE(telem_s0ix_fops, telem_s0ix_res_get, NULL, "%llu\n");
> +
>  static int telem_pss_trc_verb_show(struct seq_file *s, void *unused)
>  {
>         u32 verbosity;
> @@ -994,6 +1012,14 @@ static int __init telemetry_debugfs_init(void)
>                 goto out;
>         }
>
> +       f = debugfs_create_file("s0ix_residency_usec", S_IFREG | S_IRUGO,
> +                               debugfs_conf->telemetry_dbg_dir,
> +                               NULL, &telem_s0ix_fops);
> +       if (!f) {
> +               pr_err("s0ix_residency_usec debugfs register failed\n");
> +               goto out;
> +       }
> +
>         f = debugfs_create_file("pss_trace_verbosity", S_IFREG | S_IRUGO,
>                                 debugfs_conf->telemetry_dbg_dir, NULL,
>                                 &telem_pss_trc_verb_ops);
> --
> 1.9.1
>



-- 
With Best Regards,
Andy Shevchenko