> -----Original Message-----
> From: Tangudu, Tilak <tilak.tangudu@xxxxxxxxx>
> Sent: Thursday, July 21, 2022 3:30 PM
> To: Ewins, Jon <jon.ewins@xxxxxxxxx>; Belgaumkar, Vinay
> <vinay.belgaumkar@xxxxxxxxx>; Roper, Matthew D
> <matthew.d.roper@xxxxxxxxx>; Wilson, Chris P <chris.p.wilson@xxxxxxxxx>;
> Nikula, Jani <jani.nikula@xxxxxxxxx>; Gupta, saurabhg
> <saurabhg.gupta@xxxxxxxxx>; Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx>; Gupta,
> Anshuman <anshuman.gupta@xxxxxxxxx>; Nilawar, Badal
> <badal.nilawar@xxxxxxxxx>; Tangudu, Tilak <tilak.tangudu@xxxxxxxxx>; Deak,
> Imre <imre.deak@xxxxxxxxx>; Iddamsetty, Aravind
> <aravind.iddamsetty@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Subject: [PATCH 1/8] drm/i915: Added is_intel_rpm_allowed helper
>
> From: Tilak Tangudu <tilak.tangudu@xxxxxxxxx>
>
> Added is_intel_rpm_allowed function to query the runtime_pm status and
> disllow during suspending and resuming.
>
> v2: Return -2 if runtime pm is not allowed in runtime_pm_get and skip wakeref
> release in runtime_pm_put if wakeref value is -2. - Jani N
> Signed-off-by: Tilak Tangudu <tilak.tangudu@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/intel_runtime_pm.c | 23 ++++++++++++++++++++++-
> drivers/gpu/drm/i915/intel_runtime_pm.h | 1 +
> 2 files changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
> b/drivers/gpu/drm/i915/intel_runtime_pm.c
> index 6ed5786bcd29..704beeeb560b 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> @@ -113,7 +113,7 @@ static void untrack_intel_runtime_pm_wakeref(struct
> intel_runtime_pm *rpm,
> unsigned long flags, n;
> bool found = false;
>
> - if (unlikely(stack == -1))
> + if (unlikely(stack == -1) || unlikely(stack == -2))
> return;
>
> spin_lock_irqsave(&rpm->debug.lock, flags); @@ -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; }
> +
> +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)
AFAIR I have commented on first patch, we may need dev->power.lock here.
It is racy to test kdev->power.runtime_status with PM core can change it any time.
Please check the pm_runtime_status_suspended() kernel doc in include/linux/pm_runtime.h
Thanks,
Anshuman Gupta.
> + return false;
> + else
> + return true;
> +}
>
> static void
> intel_runtime_pm_acquire(struct intel_runtime_pm *rpm, bool wakelock) @@ -
> 354,6 +369,9 @@ static intel_wakeref_t __intel_runtime_pm_get(struct
> intel_runtime_pm *rpm,
> runtime_pm);
> int ret;
>
> + if (!is_intel_rpm_allowed(rpm))
> + return -2;
> +
> ret = pm_runtime_get_sync(rpm->kdev);
> drm_WARN_ONCE(&i915->drm, ret < 0,
> "pm_runtime_get_sync() failed: %d\n", ret); @@ -490,6
> +508,9 @@ static void __intel_runtime_pm_put(struct intel_runtime_pm *rpm,
>
> untrack_intel_runtime_pm_wakeref(rpm, wref);
>
> + if (wref == -2)
> + return;
> +
> intel_runtime_pm_release(rpm, wakelock);
>
> pm_runtime_mark_last_busy(kdev);
> 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
