Re: Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

Re: Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[함명주]

> On 04/14/2014 06:36 PM, 함명주 wrote:
> >> MyungJoo/Kyungmin,
> >>
> >> Bump. Can we accept this patch please?
> >>
> >> -Saravana
> > 
> > Nack.
> > 
> > Please note that freq_table is also an optional value, which may
> > be null.
> 
> Ah, I saw that the max_freq would be zero if freq_table was NULL and I
> assumed that it can't be NULL. But I see that the max_freq limit is not
> applied if it's zero. Thanks for catching it.
> 
> > Besides, please be aware that your code is under rcu_read_lock().
> 
> Valid point. I was just trying to keep the diff simple. No one's really
> going to be catting this file often when performance matters.
> 
> > 
> > 
> > Cheers,
> > MyungJoo.
> > 
> > ps. I'll send a related patch (avoid accessing null but not-an-error
> > pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.
> 
> I can go ahead and do this myself if you don't mind.

No, we don't need it. It was a false alarm.
Reading again, I've found that we've already made other sysfs nodes
check if either freq_table is null or its size is 0.

So, we only need to look at this available_frequencies node now.

I'll add some notes on the ABI doc for available_frequencies soon.

Cheers,
MyungJoo.

> 
> -Saravana
> 
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
> 
> 
> 
>        
>   
>          
> 

Re: Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[함명주]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=euc-kr, Size: 1559 bytes --]

> On 04/14/2014 06:36 PM, ÇÔ¸íÁÖ wrote:
> >> MyungJoo/Kyungmin,
> >>
> >> Bump. Can we accept this patch please?
> >>
> >> -Saravana
> > 
> > Nack.
> > 
> > Please note that freq_table is also an optional value, which may
> > be null.
> 
> Ah, I saw that the max_freq would be zero if freq_table was NULL and I
> assumed that it can't be NULL. But I see that the max_freq limit is not
> applied if it's zero. Thanks for catching it.
> 
> > Besides, please be aware that your code is under rcu_read_lock().
> 
> Valid point. I was just trying to keep the diff simple. No one's really
> going to be catting this file often when performance matters.
> 
> > 
> > 
> > Cheers,
> > MyungJoo.
> > 
> > ps. I'll send a related patch (avoid accessing null but not-an-error
> > pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.
> 
> I can go ahead and do this myself if you don't mind.

No, we don't need it. It was a false alarm.
Reading again, I've found that we've already made other sysfs nodes
check if either freq_table is null or its size is 0.

So, we only need to look at this available_frequencies node now.

I'll add some notes on the ABI doc for available_frequencies soon.

Cheers,
MyungJoo.

> 
> -Saravana
> 
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
> 
> 
> 
>        
>   
>          
> 
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Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/14/2014 11:30 PM, 함명주 wrote:
>> On 04/14/2014 06:36 PM, 함명주 wrote:
>>>> MyungJoo/Kyungmin,
>>>>
>>>> Bump. Can we accept this patch please?
>>>>
>>>> -Saravana
>>>
>>> Nack.
>>>
>>> Please note that freq_table is also an optional value, which may
>>> be null.
>>
>> Ah, I saw that the max_freq would be zero if freq_table was NULL and I
>> assumed that it can't be NULL. But I see that the max_freq limit is not
>> applied if it's zero. Thanks for catching it.
>>
>>> Besides, please be aware that your code is under rcu_read_lock().
>>
>> Valid point. I was just trying to keep the diff simple. No one's really
>> going to be catting this file often when performance matters.
>>
>>>
>>>
>>> Cheers,
>>> MyungJoo.
>>>
>>> ps. I'll send a related patch (avoid accessing null but not-an-error
>>> pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.
>>
>> I can go ahead and do this myself if you don't mind.
> 
> No, we don't need it. It was a false alarm.
> Reading again, I've found that we've already made other sysfs nodes
> check if either freq_table is null or its size is 0.
> 
> So, we only need to look at this available_frequencies node now.
> 
> I'll add some notes on the ABI doc for available_frequencies soon.
> 

Ah, I misunderstood your previous email. I thought you Nack-ed my patch
and decided to send your own patch to replace mine. Ok, I'll fix up mine
and send it out.

-Saravana


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/14/2014 11:30 PM, ??? wrote:
>> On 04/14/2014 06:36 PM, ??? wrote:
>>>> MyungJoo/Kyungmin,
>>>>
>>>> Bump. Can we accept this patch please?
>>>>
>>>> -Saravana
>>>
>>> Nack.
>>>
>>> Please note that freq_table is also an optional value, which may
>>> be null.
>>
>> Ah, I saw that the max_freq would be zero if freq_table was NULL and I
>> assumed that it can't be NULL. But I see that the max_freq limit is not
>> applied if it's zero. Thanks for catching it.
>>
>>> Besides, please be aware that your code is under rcu_read_lock().
>>
>> Valid point. I was just trying to keep the diff simple. No one's really
>> going to be catting this file often when performance matters.
>>
>>>
>>>
>>> Cheers,
>>> MyungJoo.
>>>
>>> ps. I'll send a related patch (avoid accessing null but not-an-error
>>> pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.
>>
>> I can go ahead and do this myself if you don't mind.
> 
> No, we don't need it. It was a false alarm.
> Reading again, I've found that we've already made other sysfs nodes
> check if either freq_table is null or its size is 0.
> 
> So, we only need to look at this available_frequencies node now.
> 
> I'll add some notes on the ABI doc for available_frequencies soon.
> 

Ah, I misunderstood your previous email. I thought you Nack-ed my patch
and decided to send your own patch to replace mine. Ok, I'll fix up mine
and send it out.

-Saravana


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH v2] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

Some devices use freq_table instead of OPP. For those devices, the
available_frequencies file shows up empty. Fix that by using freq_table to
generate the available_frequencies data when it's available.

OPP find frequency APIs also skips frequencies that have been temporarily
disabled (say, due to thermal, etc). Since available_frequencies is
supposed to show the entire list of available frequencies without taking
temporary limits into consideration, preference is given to freq_table when
available.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
---
 drivers/devfreq/devfreq.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2042ec3..527cbe2 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -912,20 +912,27 @@ static ssize_t available_frequencies_show(struct device *d,
 	struct devfreq *df = to_devfreq(d);
 	struct device *dev = df->dev.parent;
 	struct dev_pm_opp *opp;
+	unsigned int i = 0;
 	ssize_t count = 0;
 	unsigned long freq = 0;
 
-	rcu_read_lock();
-	do {
-		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
-		if (IS_ERR(opp))
-			break;
-
-		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
-				   "%lu ", freq);
-		freq++;
-	} while (1);
-	rcu_read_unlock();
+	if (df->profile->freq_table) {
+		for (i = 0; i < df->profile->max_state; i++)
+			count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
+					   "%u ", df->profile->freq_table[i]);
+	} else {
+		rcu_read_lock();
+		do {
+			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+			if (IS_ERR(opp))
+				break;
+
+			count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
+					   "%lu ", freq);
+			freq++;
+		} while (1);
+		rcu_read_unlock();
+	}
 
 	/* Truncate the trailing space */
 	if (count)
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH v2] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

Some devices use freq_table instead of OPP. For those devices, the
available_frequencies file shows up empty. Fix that by using freq_table to
generate the available_frequencies data when it's available.

OPP find frequency APIs also skips frequencies that have been temporarily
disabled (say, due to thermal, etc). Since available_frequencies is
supposed to show the entire list of available frequencies without taking
temporary limits into consideration, preference is given to freq_table when
available.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
---
 drivers/devfreq/devfreq.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2042ec3..527cbe2 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -912,20 +912,27 @@ static ssize_t available_frequencies_show(struct device *d,
 	struct devfreq *df = to_devfreq(d);
 	struct device *dev = df->dev.parent;
 	struct dev_pm_opp *opp;
+	unsigned int i = 0;
 	ssize_t count = 0;
 	unsigned long freq = 0;
 
-	rcu_read_lock();
-	do {
-		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
-		if (IS_ERR(opp))
-			break;
-
-		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
-				   "%lu ", freq);
-		freq++;
-	} while (1);
-	rcu_read_unlock();
+	if (df->profile->freq_table) {
+		for (i = 0; i < df->profile->max_state; i++)
+			count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
+					   "%u ", df->profile->freq_table[i]);
+	} else {
+		rcu_read_lock();
+		do {
+			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+			if (IS_ERR(opp))
+				break;
+
+			count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
+					   "%lu ", freq);
+			freq++;
+		} while (1);
+		rcu_read_unlock();
+	}
 
 	/* Truncate the trailing space */
 	if (count)
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/15/2014 11:41 AM, Saravana Kannan wrote:
> Ah, I misunderstood your previous email. I thought you Nack-ed my patch
> and decided to send your own patch to replace mine. Ok, I'll fix up mine
> and send it out.

MyungJoo/Kyungmin,

I sent out an updated patch. Can you please take a look?

Thanks,
Saravana


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/15/2014 11:41 AM, Saravana Kannan wrote:
> Ah, I misunderstood your previous email. I thought you Nack-ed my patch
> and decided to send your own patch to replace mine. Ok, I'll fix up mine
> and send it out.

MyungJoo/Kyungmin,

I sent out an updated patch. Can you please take a look?

Thanks,
Saravana


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/14/2014 06:36 PM, 함명주 wrote:
>> MyungJoo/Kyungmin,
>>
>> Bump. Can we accept this patch please?
>>
>> -Saravana
> 
> Nack.
> 
> Please note that freq_table is also an optional value, which may
> be null.

Ah, I saw that the max_freq would be zero if freq_table was NULL and I
assumed that it can't be NULL. But I see that the max_freq limit is not
applied if it's zero. Thanks for catching it.

> Besides, please be aware that your code is under rcu_read_lock().

Valid point. I was just trying to keep the diff simple. No one's really
going to be catting this file often when performance matters.

> 
> 
> Cheers,
> MyungJoo.
> 
> ps. I'll send a related patch (avoid accessing null but not-an-error
> pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.

I can go ahead and do this myself if you don't mind.

-Saravana

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

On 04/14/2014 06:36 PM, ??? wrote:
>> MyungJoo/Kyungmin,
>>
>> Bump. Can we accept this patch please?
>>
>> -Saravana
> 
> Nack.
> 
> Please note that freq_table is also an optional value, which may
> be null.

Ah, I saw that the max_freq would be zero if freq_table was NULL and I
assumed that it can't be NULL. But I see that the max_freq limit is not
applied if it's zero. Thanks for catching it.

> Besides, please be aware that your code is under rcu_read_lock().

Valid point. I was just trying to keep the diff simple. No one's really
going to be catting this file often when performance matters.

> 
> 
> Cheers,
> MyungJoo.
> 
> ps. I'll send a related patch (avoid accessing null but not-an-error
> pointer at other sysfs nodes). Thank you for letting me catch such bugs anyway.

I can go ahead and do this myself if you don't mind.

-Saravana

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

Re: [PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

MyungJoo/Kyungmin,

Bump. Can we accept this patch please?

-Saravana


On 04/10/2014 07:54 PM, Saravana Kannan wrote:
> Some devices use freq_table instead of OPP. For those devices, the
> available_frequencies file shows up empty. Fix that by using freq_table to
> generate the available_frequencies data when OPP is not present.
>
> Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
> ---
>   drivers/devfreq/devfreq.c | 15 +++++++++++----
>   1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 2042ec3..a715d15 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -912,19 +912,26 @@ static ssize_t available_frequencies_show(struct device *d,
>   	struct devfreq *df = to_devfreq(d);
>   	struct device *dev = df->dev.parent;
>   	struct dev_pm_opp *opp;
> +	unsigned int i = 0, max_state = df->profile->max_state;
> +	bool use_opp;
>   	ssize_t count = 0;
>   	unsigned long freq = 0;
>
>   	rcu_read_lock();
> +	use_opp = dev_pm_opp_get_opp_count(dev) > 0;
>   	do {
> -		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
> -		if (IS_ERR(opp))
> -			break;
> +		if (use_opp) {
> +			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
> +			if (IS_ERR(opp))
> +				break;
> +		} else {
> +			freq = df->profile->freq_table[i++];
> +		}
>
>   		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>   				   "%lu ", freq);
>   		freq++;
> -	} while (1);
> +	} while (use_opp || (!use_opp && i < max_state));
>   	rcu_read_unlock();
>
>   	/* Truncate the trailing space */
>


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

MyungJoo/Kyungmin,

Bump. Can we accept this patch please?

-Saravana


On 04/10/2014 07:54 PM, Saravana Kannan wrote:
> Some devices use freq_table instead of OPP. For those devices, the
> available_frequencies file shows up empty. Fix that by using freq_table to
> generate the available_frequencies data when OPP is not present.
>
> Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
> ---
>   drivers/devfreq/devfreq.c | 15 +++++++++++----
>   1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 2042ec3..a715d15 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -912,19 +912,26 @@ static ssize_t available_frequencies_show(struct device *d,
>   	struct devfreq *df = to_devfreq(d);
>   	struct device *dev = df->dev.parent;
>   	struct dev_pm_opp *opp;
> +	unsigned int i = 0, max_state = df->profile->max_state;
> +	bool use_opp;
>   	ssize_t count = 0;
>   	unsigned long freq = 0;
>
>   	rcu_read_lock();
> +	use_opp = dev_pm_opp_get_opp_count(dev) > 0;
>   	do {
> -		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
> -		if (IS_ERR(opp))
> -			break;
> +		if (use_opp) {
> +			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
> +			if (IS_ERR(opp))
> +				break;
> +		} else {
> +			freq = df->profile->freq_table[i++];
> +		}
>
>   		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
>   				   "%lu ", freq);
>   		freq++;
> -	} while (1);
> +	} while (use_opp || (!use_opp && i < max_state));
>   	rcu_read_unlock();
>
>   	/* Truncate the trailing space */
>


-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

Some devices use freq_table instead of OPP. For those devices, the
available_frequencies file shows up empty. Fix that by using freq_table to
generate the available_frequencies data when OPP is not present.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
---
 drivers/devfreq/devfreq.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2042ec3..a715d15 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -912,19 +912,26 @@ static ssize_t available_frequencies_show(struct device *d,
 	struct devfreq *df = to_devfreq(d);
 	struct device *dev = df->dev.parent;
 	struct dev_pm_opp *opp;
+	unsigned int i = 0, max_state = df->profile->max_state;
+	bool use_opp;
 	ssize_t count = 0;
 	unsigned long freq = 0;
 
 	rcu_read_lock();
+	use_opp = dev_pm_opp_get_opp_count(dev) > 0;
 	do {
-		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
-		if (IS_ERR(opp))
-			break;
+		if (use_opp) {
+			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+			if (IS_ERR(opp))
+				break;
+		} else {
+			freq = df->profile->freq_table[i++];
+		}
 
 		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
 				   "%lu ", freq);
 		freq++;
-	} while (1);
+	} while (use_opp || (!use_opp && i < max_state));
 	rcu_read_unlock();
 
 	/* Truncate the trailing space */
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH] PM / devfreq: Use freq_table for available_frequencies

[Saravana Kannan]

Some devices use freq_table instead of OPP. For those devices, the
available_frequencies file shows up empty. Fix that by using freq_table to
generate the available_frequencies data when OPP is not present.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
---
 drivers/devfreq/devfreq.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2042ec3..a715d15 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -912,19 +912,26 @@ static ssize_t available_frequencies_show(struct device *d,
 	struct devfreq *df = to_devfreq(d);
 	struct device *dev = df->dev.parent;
 	struct dev_pm_opp *opp;
+	unsigned int i = 0, max_state = df->profile->max_state;
+	bool use_opp;
 	ssize_t count = 0;
 	unsigned long freq = 0;
 
 	rcu_read_lock();
+	use_opp = dev_pm_opp_get_opp_count(dev) > 0;
 	do {
-		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
-		if (IS_ERR(opp))
-			break;
+		if (use_opp) {
+			opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+			if (IS_ERR(opp))
+				break;
+		} else {
+			freq = df->profile->freq_table[i++];
+		}
 
 		count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
 				   "%lu ", freq);
 		freq++;
-	} while (1);
+	} while (use_opp || (!use_opp && i < max_state));
 	rcu_read_unlock();
 
 	/* Truncate the trailing space */
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation