Re: [Intel-gfx] [PATCH 04/11] drm/i915: Added is_intel_rpm_allowed helper

["Gupta, Anshuman" <anshuman.gupta@intel.com>]

> -----Original Message-----
> From: Tangudu, Tilak <tilak.tangudu@intel.com>
> Sent: Tuesday, June 21, 2022 6:05 PM
> To: intel-gfx@lists.freedesktop.org; Ewins, Jon <jon.ewins@intel.com>; Vivi,
> Rodrigo <rodrigo.vivi@intel.com>; Belgaumkar, Vinay
> <vinay.belgaumkar@intel.com>; Wilson, Chris P <chris.p.wilson@intel.com>;
> Dixit, Ashutosh <ashutosh.dixit@intel.com>; Nilawar, Badal
> <badal.nilawar@intel.com>; Gupta, Anshuman <anshuman.gupta@intel.com>;
> Tangudu, Tilak <tilak.tangudu@intel.com>; Roper, Matthew D
> <matthew.d.roper@intel.com>; Gupta, saurabhg <saurabhg.gupta@intel.com>;
> Iddamsetty, Aravind <aravind.iddamsetty@intel.com>; Sundaresan, Sujaritha
> <sujaritha.sundaresan@intel.com>
> Subject: [PATCH 04/11] drm/i915: Added is_intel_rpm_allowed helper
> 
> Added is_intel_rpm_allowed function to query the runtime_pm status and
> disllow during suspending and resuming.
This seems a hack,
Not sure if we have better way to handle it.
May be check this in intel_pm_runtime_{get,put} to keep entire code simple ?
> 
> Signed-off-by: Tilak Tangudu <tilak.tangudu@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_runtime_pm.c | 15 +++++++++++++++
> drivers/gpu/drm/i915/intel_runtime_pm.h |  1 +
>  2 files changed, 16 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
> b/drivers/gpu/drm/i915/intel_runtime_pm.c
> index 6ed5786bcd29..3759a8596084 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> @@ -320,6 +320,21 @@ untrack_all_intel_runtime_pm_wakerefs(struct
> intel_runtime_pm *rpm)  }
> 
>  #endif
> +static int intel_runtime_pm_status(struct intel_runtime_pm *rpm) {
> +	return rpm->kdev->power.runtime_status; }
This is racy in principal, we need a kdev->power lock here. 
Regards,
Anshuman Gupta.
> +
> +bool is_intel_rpm_allowed(struct intel_runtime_pm *rpm) {
> +	int rpm_status;
> +
> +	rpm_status = intel_runtime_pm_status(rpm);
> +	if (rpm_status == RPM_RESUMING || rpm_status ==
> RPM_SUSPENDING)
> +		return false;
> +	else
> +		return true;
> +}
> 
>  static void
>  intel_runtime_pm_acquire(struct intel_runtime_pm *rpm, bool wakelock) diff --
> git a/drivers/gpu/drm/i915/intel_runtime_pm.h
> b/drivers/gpu/drm/i915/intel_runtime_pm.h
> index d9160e3ff4af..99418c3a934a 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.h
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.h
> @@ -173,6 +173,7 @@ void intel_runtime_pm_init_early(struct
> intel_runtime_pm *rpm);  void intel_runtime_pm_enable(struct
> intel_runtime_pm *rpm);  void intel_runtime_pm_disable(struct
> intel_runtime_pm *rpm);  void intel_runtime_pm_driver_release(struct
> intel_runtime_pm *rpm);
> +bool is_intel_rpm_allowed(struct intel_runtime_pm *rpm);
> 
>  intel_wakeref_t intel_runtime_pm_get(struct intel_runtime_pm *rpm);
> intel_wakeref_t intel_runtime_pm_get_if_in_use(struct intel_runtime_pm
> *rpm);
> --
> 2.25.1