2022-06-09 20:12:17

by Caleb Connolly

Subject: [PATCH] dmaengine: qcom: bam_dma: fix runtime PM underflow

When PM runtime is disabled, pm_runtime_get() isn't called, but
pm_runtime_put() still is. Fix this by creating a matching wrapper
on pm_runtime_put_autosuspend().

Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
Signed-off-by: Caleb Connolly <[email protected]>
---
drivers/dma/qcom/bam_dma.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 87f6ca1541cf..a36dedee262e 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -566,6 +566,14 @@ static int bam_pm_runtime_get_sync(struct device *dev)
return 0;
}

+static int bam_pm_runtime_put_autosuspend(struct device *dev)
+{
+ if (pm_runtime_enabled(dev))
+ return pm_runtime_put_autosuspend(dev);
+
+ return 0;
+}
+
/**
* bam_free_chan - Frees dma resources associated with specific channel
* @chan: specified channel
@@ -617,7 +625,7 @@ static void bam_free_chan(struct dma_chan *chan)

err:
pm_runtime_mark_last_busy(bdev->dev);
- pm_runtime_put_autosuspend(bdev->dev);
+ bam_pm_runtime_put_autosuspend(bdev->dev);
}

/**
@@ -793,7 +801,7 @@ static int bam_pause(struct dma_chan *chan)
bchan->paused = 1;
spin_unlock_irqrestore(&bchan->vc.lock, flag);
pm_runtime_mark_last_busy(bdev->dev);
- pm_runtime_put_autosuspend(bdev->dev);
+ bam_pm_runtime_put_autosuspend(bdev->dev);

return 0;
}
@@ -819,7 +827,7 @@ static int bam_resume(struct dma_chan *chan)
bchan->paused = 0;
spin_unlock_irqrestore(&bchan->vc.lock, flag);
pm_runtime_mark_last_busy(bdev->dev);
- pm_runtime_put_autosuspend(bdev->dev);
+ bam_pm_runtime_put_autosuspend(bdev->dev);

return 0;
}
@@ -936,7 +944,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
}

pm_runtime_mark_last_busy(bdev->dev);
- pm_runtime_put_autosuspend(bdev->dev);
+ bam_pm_runtime_put_autosuspend(bdev->dev);

return IRQ_HANDLED;
}
@@ -1111,7 +1119,7 @@ static void bam_start_dma(struct bam_chan *bchan)
bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));

pm_runtime_mark_last_busy(bdev->dev);
- pm_runtime_put_autosuspend(bdev->dev);
+ bam_pm_runtime_put_autosuspend(bdev->dev);
}

/**
--
2.36.1

2022-06-12 00:34:18

by Steev Klimaszewski

Subject: Re: [PATCH] dmaengine: qcom: bam_dma: fix runtime PM underflow

Hi Caleb,

On 6/9/22 2:50 PM, Caleb Connolly wrote:
> When PM runtime is disabled, pm_runtime_get() isn't called, but
> pm_runtime_put() still is. Fix this by creating a matching wrapper
> on pm_runtime_put_autosuspend().
>
> Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
> Signed-off-by: Caleb Connolly <[email protected]>
> ---
> drivers/dma/qcom/bam_dma.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
> index 87f6ca1541cf..a36dedee262e 100644
> --- a/drivers/dma/qcom/bam_dma.c
> +++ b/drivers/dma/qcom/bam_dma.c
> @@ -566,6 +566,14 @@ static int bam_pm_runtime_get_sync(struct device *dev)
> return 0;
> }
>
> +static int bam_pm_runtime_put_autosuspend(struct device *dev)
> +{
> + if (pm_runtime_enabled(dev))
> + return pm_runtime_put_autosuspend(dev);
> +
> + return 0;
> +}
> +
> /**
> * bam_free_chan - Frees dma resources associated with specific channel
> * @chan: specified channel
> @@ -617,7 +625,7 @@ static void bam_free_chan(struct dma_chan *chan)
>
> err:
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**
> @@ -793,7 +801,7 @@ static int bam_pause(struct dma_chan *chan)
> bchan->paused = 1;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -819,7 +827,7 @@ static int bam_resume(struct dma_chan *chan)
> bchan->paused = 0;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -936,7 +944,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
> }
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return IRQ_HANDLED;
> }
> @@ -1111,7 +1119,7 @@ static void bam_start_dma(struct bam_chan *bchan)
> bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**

I've tested this patch here and no longer see the logs filling up with
messages about Runtime PM underflows.  Tested on the Lenovo Yoga C630.


Tested-by: Steev Klimaszewski <[email protected]>

2022-06-16 14:35:56

by Vinod Koul

Subject: Re: [PATCH] dmaengine: qcom: bam_dma: fix runtime PM underflow

On 09-06-22, 20:50, Caleb Connolly wrote:
> When PM runtime is disabled, pm_runtime_get() isn't called, but
> pm_runtime_put() still is. Fix this by creating a matching wrapper
> on pm_runtime_put_autosuspend().
>
> Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
> Signed-off-by: Caleb Connolly <[email protected]>
> ---
> drivers/dma/qcom/bam_dma.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
> index 87f6ca1541cf..a36dedee262e 100644
> --- a/drivers/dma/qcom/bam_dma.c
> +++ b/drivers/dma/qcom/bam_dma.c
> @@ -566,6 +566,14 @@ static int bam_pm_runtime_get_sync(struct device *dev)
> return 0;
> }
>
> +static int bam_pm_runtime_put_autosuspend(struct device *dev)
> +{
> + if (pm_runtime_enabled(dev))
> + return pm_runtime_put_autosuspend(dev);
> +
> + return 0;
> +}

should we really do a wrapper to fix this ;-) I would think dropping the
get wrapper and calling pm_runtime_get() unconditionally would be
better..?

> +
> /**
> * bam_free_chan - Frees dma resources associated with specific channel
> * @chan: specified channel
> @@ -617,7 +625,7 @@ static void bam_free_chan(struct dma_chan *chan)
>
> err:
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**
> @@ -793,7 +801,7 @@ static int bam_pause(struct dma_chan *chan)
> bchan->paused = 1;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -819,7 +827,7 @@ static int bam_resume(struct dma_chan *chan)
> bchan->paused = 0;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -936,7 +944,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
> }
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return IRQ_HANDLED;
> }
> @@ -1111,7 +1119,7 @@ static void bam_start_dma(struct bam_chan *bchan)
> bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**
> --
> 2.36.1

--
~Vinod

2022-06-28 12:24:18

by Caleb Connolly

Subject: Re: [PATCH] dmaengine: qcom: bam_dma: fix runtime PM underflow

On 16/06/2022 15:00, Vinod Koul wrote:
> On 09-06-22, 20:50, Caleb Connolly wrote:
>> When PM runtime is disabled, pm_runtime_get() isn't called, but
>> pm_runtime_put() still is. Fix this by creating a matching wrapper
>> on pm_runtime_put_autosuspend().
>>
>> Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
>> Signed-off-by: Caleb Connolly <[email protected]>
>> ---
>> drivers/dma/qcom/bam_dma.c | 18 +++++++++++++-----
>> 1 file changed, 13 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
>> index 87f6ca1541cf..a36dedee262e 100644
>> --- a/drivers/dma/qcom/bam_dma.c
>> +++ b/drivers/dma/qcom/bam_dma.c
>> @@ -566,6 +566,14 @@ static int bam_pm_runtime_get_sync(struct device *dev)
>> return 0;
>> }
>>
>> +static int bam_pm_runtime_put_autosuspend(struct device *dev)
>> +{
>> + if (pm_runtime_enabled(dev))
>> + return pm_runtime_put_autosuspend(dev);
>> +
>> + return 0;
>> +}
>
> should we really do a wrapper to fix this ;-) I would think dropping the
> get wrapper and calling pm_runtime_get() unconditionally would be
> better..?
The original pm_runtime_get() wrapper was added because _get() returns -EACCES
if PM is disabled for the device, I've read through some of the pm_runtime docs
and I don't see any way to handle this nicely in the framework. I think the real
fix will have to be in pm_runtime.

I can rework this to explicitly check for -EACCES on every _get() call, but we
still need to check if pm_runtime is enabled before calling _put().
>
>> +
>> /**
>> * bam_free_chan - Frees dma resources associated with specific channel
>> * @chan: specified channel
>> @@ -617,7 +625,7 @@ static void bam_free_chan(struct dma_chan *chan)
>>
>> err:
>> pm_runtime_mark_last_busy(bdev->dev);
>> - pm_runtime_put_autosuspend(bdev->dev);
>> + bam_pm_runtime_put_autosuspend(bdev->dev);
>> }
>>
>> /**
>> @@ -793,7 +801,7 @@ static int bam_pause(struct dma_chan *chan)
>> bchan->paused = 1;
>> spin_unlock_irqrestore(&bchan->vc.lock, flag);
>> pm_runtime_mark_last_busy(bdev->dev);
>> - pm_runtime_put_autosuspend(bdev->dev);
>> + bam_pm_runtime_put_autosuspend(bdev->dev);
>>
>> return 0;
>> }
>> @@ -819,7 +827,7 @@ static int bam_resume(struct dma_chan *chan)
>> bchan->paused = 0;
>> spin_unlock_irqrestore(&bchan->vc.lock, flag);
>> pm_runtime_mark_last_busy(bdev->dev);
>> - pm_runtime_put_autosuspend(bdev->dev);
>> + bam_pm_runtime_put_autosuspend(bdev->dev);
>>
>> return 0;
>> }
>> @@ -936,7 +944,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
>> }
>>
>> pm_runtime_mark_last_busy(bdev->dev);
>> - pm_runtime_put_autosuspend(bdev->dev);
>> + bam_pm_runtime_put_autosuspend(bdev->dev);
>>
>> return IRQ_HANDLED;
>> }
>> @@ -1111,7 +1119,7 @@ static void bam_start_dma(struct bam_chan *bchan)
>> bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
>>
>> pm_runtime_mark_last_busy(bdev->dev);
>> - pm_runtime_put_autosuspend(bdev->dev);
>> + bam_pm_runtime_put_autosuspend(bdev->dev);
>> }
>>
>> /**
>> --
>> 2.36.1
>

--
Kind Regards,
Caleb (they/he)

2022-07-02 09:07:17

by Yassine Oudjana

Subject: Re: [PATCH] dmaengine: qcom: bam_dma: fix runtime PM underflow

From: Yassine Oudjana <[email protected]>

From: Yassine Oudjana <[email protected]>

On Thu, 9 Jun 2022 20:50:43 +0100, Caleb Connolly <[email protected]> wrote:
>
> When PM runtime is disabled, pm_runtime_get() isn't called, but
> pm_runtime_put() still is. Fix this by creating a matching wrapper
> on pm_runtime_put_autosuspend().
>
> Fixes: dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
> Signed-off-by: Caleb Connolly <[email protected]>
> ---
> drivers/dma/qcom/bam_dma.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
> index 87f6ca1541cf..a36dedee262e 100644
> --- a/drivers/dma/qcom/bam_dma.c
> +++ b/drivers/dma/qcom/bam_dma.c
> @@ -566,6 +566,14 @@ static int bam_pm_runtime_get_sync(struct device *dev)
> return 0;
> }
>
> +static int bam_pm_runtime_put_autosuspend(struct device *dev)
> +{
> + if (pm_runtime_enabled(dev))
> + return pm_runtime_put_autosuspend(dev);
> +
> + return 0;
> +}
> +
> /**
> * bam_free_chan - Frees dma resources associated with specific channel
> * @chan: specified channel
> @@ -617,7 +625,7 @@ static void bam_free_chan(struct dma_chan *chan)
>
> err:
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**
> @@ -793,7 +801,7 @@ static int bam_pause(struct dma_chan *chan)
> bchan->paused = 1;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -819,7 +827,7 @@ static int bam_resume(struct dma_chan *chan)
> bchan->paused = 0;
> spin_unlock_irqrestore(&bchan->vc.lock, flag);
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return 0;
> }
> @@ -936,7 +944,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
> }
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
>
> return IRQ_HANDLED;
> }
> @@ -1111,7 +1119,7 @@ static void bam_start_dma(struct bam_chan *bchan)
> bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
>
> pm_runtime_mark_last_busy(bdev->dev);
> - pm_runtime_put_autosuspend(bdev->dev);
> + bam_pm_runtime_put_autosuspend(bdev->dev);
> }
>
> /**
> --
> 2.36.1
>

Thanks for the fix!

On the Xiaomi Mi Note 2:

Tested-by: Yassine Oudjana <[email protected]>