Re: [PATCH v1] platform/x86: intel_pmc_core: promote S0ix failure warn() to WARN()

From: Hans de Goede
Date: Thu Oct 27 2022 - 11:40:51 EST


Hi,

On 10/27/22 17:19, Sven van Ashbrook wrote:
> The "failure to enter S0ix" warning is critically important for monitoring
> and debugging power regressions, both in the field and in the test lab.
>
> Promote from lower-case warn() to upper-case WARN() so that it becomes
> more prominent, and gets picked up as part of existing monitoring
> infrastructure, which typically focuses on WARN() and ignores warn()
> type log messages.
>
> Signed-off-by: Sven van Ashbrook <svenva@xxxxxxxxxxxx>

WARN() is really only intended for internal kernel bugs and not for
hw misbehaving, so I'm not a fan of the change you are suggesting here.

Intel folks, do you have an opinion on this ?

Regards,

Hans


> ---
> Against v6.1-rc2
>
> drivers/platform/x86/intel/pmc/core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
> index a1fe1e0dcf4a5..834f0352c0edf 100644
> --- a/drivers/platform/x86/intel/pmc/core.c
> +++ b/drivers/platform/x86/intel/pmc/core.c
> @@ -2125,7 +2125,7 @@ static __maybe_unused int pmc_core_resume(struct device *dev)
> }
>
> /* The real interesting case - S0ix failed - lets ask PMC why. */
> - dev_warn(dev, "CPU did not enter SLP_S0!!! (S0ix cnt=%llu)\n",
> + dev_WARN(dev, "CPU did not enter SLP_S0!!! (S0ix cnt=%llu)\n",
> pmcdev->s0ix_counter);
> if (pmcdev->map->slps0_dbg_maps)
> pmc_core_slps0_display(pmcdev, dev, NULL);