Re: [PATCH 07/11] drm/i915: kill dev_priv->pc8.gpu_idle

Paulo Zanoni
2014-02-28T20:11:47Z

2014-02-28 10:50 GMT-03:00 Imre Deak <imre.deak@intel.com>:
> On Fri, 2014-02-21 at 13:52 -0300, Paulo Zanoni wrote:
>> From: Paulo Zanoni <paulo.r.zanoni@intel.com>
>>
>> Since the addition of dev_priv->mm.busy, there's no more need for
>> dev_priv->pc8.gpu_idle, so kill it.
>>
>> Notice that when you remove gpu_idle, hsw_package_c8_gpu_idle and
>> hsw_package_c8_gpu_busy become identical to hsw_enable_package_c8 and
>> hsw_disable_package_c8, so just use them.
>>
>> Also, when we boot the machine, dev_priv->mm.busy initially considers
>> the machine as idle. This is opposed to dev_priv->pc8.gpu_idle, which
>> considered it busy. So dev_priv->pc8.disable_count has to be
>> initalized to 1 now.
>>
>> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
>> ---
>> drivers/gpu/drm/i915/i915_debugfs.c | 2 +-
>> drivers/gpu/drm/i915/i915_drv.h | 10 ++++------
>> drivers/gpu/drm/i915/intel_display.c | 30 ++----------------------------
>> drivers/gpu/drm/i915/intel_pm.c | 3 +--
>> 4 files changed, 8 insertions(+), 37 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
>> index 34e347f..62d0c0915 100644
>> --- a/drivers/gpu/drm/i915/i915_debugfs.c
>> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
>> @@ -2014,7 +2014,7 @@ static int i915_pc8_status(struct seq_file *m, void *unused)
>> mutex_lock(&dev_priv->pc8.lock);
>> seq_printf(m, "Requirements met: %s\n",
>> yesno(dev_priv->pc8.requirements_met));
>> - seq_printf(m, "GPU idle: %s\n", yesno(dev_priv->pc8.gpu_idle));
>> + seq_printf(m, "GPU idle: %s\n", yesno(!dev_priv->mm.busy));
>> seq_printf(m, "Disable count: %d\n", dev_priv->pc8.disable_count);
>> seq_printf(m, "IRQs disabled: %s\n",
>> yesno(dev_priv->pc8.irqs_disabled));
>> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>> index a5caa7e..2a2a3a9 100644
>> --- a/drivers/gpu/drm/i915/i915_drv.h
>> +++ b/drivers/gpu/drm/i915/i915_drv.h
>> @@ -1321,11 +1321,10 @@ struct ilk_wm_values {
>> * Ideally every piece of our code that needs PC8+ disabled would call
>> * hsw_disable_package_c8, which would increment disable_count and prevent the
>> * system from reaching PC8+. But we don't have a symmetric way to do this for
>> - * everything, so we have the requirements_met and gpu_idle variables. When we
>> - * switch requirements_met or gpu_idle to true we decrease disable_count, and
>> - * increase it in the opposite case. The requirements_met variable is true when
>> - * all the CRTCs, encoders and the power well are disabled. The gpu_idle
>> - * variable is true when the GPU is idle.
>> + * everything, so we have the requirements_met variable. When we switch
>> + * requirements_met to true we decrease disable_count, and increase it in the
>> + * opposite case. The requirements_met variable is true when all the CRTCs,
>> + * encoders and the power well are disabled.
>> *
>> * In addition to everything, we only actually enable PC8+ if disable_count
>> * stays at zero for at least some seconds. This is implemented with the
>> @@ -1348,7 +1347,6 @@ struct ilk_wm_values {
>> */
>> struct i915_package_c8 {
>> bool requirements_met;
>> - bool gpu_idle;
>> bool irqs_disabled;
>> /* Only true after the delayed work task actually enables it. */
>> bool enabled;
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index c64fb7f..796a116 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -6812,32 +6812,6 @@ done:
>> mutex_unlock(&dev_priv->pc8.lock);
>> }
>>
>> -static void hsw_package_c8_gpu_idle(struct drm_i915_private *dev_priv)
>> -{
>> - if (!HAS_PC8(dev_priv->dev))
>> - return;
>> -
>> - mutex_lock(&dev_priv->pc8.lock);
>> - if (!dev_priv->pc8.gpu_idle) {
>> - dev_priv->pc8.gpu_idle = true;
>> - __hsw_enable_package_c8(dev_priv);
>> - }
>> - mutex_unlock(&dev_priv->pc8.lock);
>> -}
>> -
>> -static void hsw_package_c8_gpu_busy(struct drm_i915_private *dev_priv)
>> -{
>> - if (!HAS_PC8(dev_priv->dev))
>> - return;
>> -
>> - mutex_lock(&dev_priv->pc8.lock);
>> - if (dev_priv->pc8.gpu_idle) {
>> - dev_priv->pc8.gpu_idle = false;
>> - __hsw_disable_package_c8(dev_priv);
>> - }
>> - mutex_unlock(&dev_priv->pc8.lock);
>> -}
>> -
>> #define for_each_power_domain(domain, mask) \
>> for ((domain) = 0; (domain) < POWER_DOMAIN_NUM; (domain)++) \
>> if ((1 << (domain)) & (mask))
>> @@ -8195,7 +8169,7 @@ void intel_mark_busy(struct drm_device *dev)
>> if (dev_priv->mm.busy)
>> return;
>>
>> - hsw_package_c8_gpu_busy(dev_priv);
>> + hsw_disable_package_c8(dev_priv);
>> i915_update_gfx_val(dev_priv);
>> dev_priv->mm.busy = true;
>> }
>> @@ -8224,7 +8198,7 @@ void intel_mark_idle(struct drm_device *dev)
>> gen6_rps_idle(dev->dev_private);
>>
>> out:
>> - hsw_package_c8_gpu_idle(dev_priv);
>> + hsw_enable_package_c8(dev_priv);
>> }
>>
>> void intel_mark_fb_busy(struct drm_i915_gem_object *obj,
>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>> index a6b877a..50b80bb 100644
>> --- a/drivers/gpu/drm/i915/intel_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>> @@ -5786,10 +5786,9 @@ void intel_pm_setup(struct drm_device *dev)
>>
>> mutex_init(&dev_priv->pc8.lock);
>> dev_priv->pc8.requirements_met = false;
>> - dev_priv->pc8.gpu_idle = false;
>> dev_priv->pc8.irqs_disabled = false;
>> dev_priv->pc8.enabled = false;
>> - dev_priv->pc8.disable_count = 2; /* requirements_met + gpu_idle */
>> + dev_priv->pc8.disable_count = 1; /* requirements_met */
>
> This looks ok, but it's part of "Merge PC8 with runtime PM, v2" along
> with patch 1/11, so they can be skipped from this patchset.

Yes. Since you spotted some potential conflicts between this series
and yours, I decided to send "Merge PC8 with runtime PM v2" in a way
that it's independent form this series: it just contains the fixes
that are necessary, avoiding some of the conflicts you detected. So we
can just merge that series instead of this, if wanted.

>
> --Imre
>
>
>> INIT_DELAYED_WORK(&dev_priv->pc8.enable_work, hsw_enable_pc8_work);
>> INIT_DELAYED_WORK(&dev_priv->rps.delayed_resume_work,
>> intel_gen6_powersave_work);
>

--
Paulo Zanoni