Re: [PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
On Sat, Mar 15, 2014 at 7:34 AM, Rafael J. Wysocki wrote:
> On Friday, March 14, 2014 02:03:56 PM dirk.brande...@gmail.com wrote:
>> +++ b/drivers/cpufreq/cpufreq.c
>> @@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
>> *dev,
>> }
>> }
>>
>> + if (cpufreq_driver->stop)
>
> What about doing
>
> + if (cpufreq_driver->setpolicy && cpufreq_driver->stop)
>
> here instead? That would make it clear where the new callback belongs.
This is called after stopping governor and so might be useful for ->target()
drivers. So, wouldn't be a bad option if we keep it available for all..
@Dirk: I thought about the solution I mentioned in another mail. And it looks
like I will end up getting a similar solution. So, we will go with
your solution.
Just few changes for your solution..
You need to call ->stop() only for the last CPU of every policy and not for
every CPU, so you need something like this:
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 19d25a8..78d41c0 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1371,6 +1371,8 @@ static int __cpufreq_remove_dev_prepare(struct
device *dev,
__func__, new_cpu, cpu);
}
}
+ } else if (cpufreq_driver->stop) {
+ cpufreq_driver->stop(policy);
}
return 0;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
On Sat, Mar 15, 2014 at 7:34 AM, Rafael J. Wysocki r...@rjwysocki.net wrote:
On Friday, March 14, 2014 02:03:56 PM dirk.brande...@gmail.com wrote:
+++ b/drivers/cpufreq/cpufreq.c
@@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
}
}
+ if (cpufreq_driver-stop)
What about doing
+ if (cpufreq_driver-setpolicy cpufreq_driver-stop)
here instead? That would make it clear where the new callback belongs.
This is called after stopping governor and so might be useful for -target()
drivers. So, wouldn't be a bad option if we keep it available for all..
@Dirk: I thought about the solution I mentioned in another mail. And it looks
like I will end up getting a similar solution. So, we will go with
your solution.
Just few changes for your solution..
You need to call -stop() only for the last CPU of every policy and not for
every CPU, so you need something like this:
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 19d25a8..78d41c0 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1371,6 +1371,8 @@ static int __cpufreq_remove_dev_prepare(struct
device *dev,
__func__, new_cpu, cpu);
}
}
+ } else if (cpufreq_driver-stop) {
+ cpufreq_driver-stop(policy);
}
return 0;
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
On Friday, March 14, 2014 02:03:56 PM dirk.brande...@gmail.com wrote:
> From: Dirk Brandewie
>
> This callback allows the driver to do clean up before the CPU is
> completely down and its state cannot be modified. This is used
> by the intel_pstate driver to reduce the requested P state prior to
> the core going away. This is required because the requested P state
> of the offline core is used to select the package P state. This
> effectively sets the floor package P state to the requested P state on
> the offline core.
>
> Signed-off-by: Dirk Brandewie
> ---
> Documentation/cpu-freq/cpu-drivers.txt | 8 +++-
> drivers/cpufreq/cpufreq.c | 3 +++
> include/linux/cpufreq.h| 1 +
> 3 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/cpu-freq/cpu-drivers.txt
> b/Documentation/cpu-freq/cpu-drivers.txt
> index 8b1a445..79def80 100644
> --- a/Documentation/cpu-freq/cpu-drivers.txt
> +++ b/Documentation/cpu-freq/cpu-drivers.txt
> @@ -61,7 +61,13 @@ target_index - See below on the
> differences.
>
> And optionally
>
> -cpufreq_driver.exit -A pointer to a per-CPU cleanup function.
> +cpufreq_driver.exit -A pointer to a per-CPU cleanup
> + function called during CPU_POST_DEAD
> + phase of cpu hotplug process.
> +
> +cpufreq_driver.stop -A pointer to a per-CPU stop function
> + called during CPU_DOWN_PREPARE phase of
> + cpu hotplug process.
>
> cpufreq_driver.resume - A pointer to a per-CPU resume function
> which is called with interrupts disabled
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index cf485d9..0d430d7 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
> *dev,
> }
> }
>
> + if (cpufreq_driver->stop)
What about doing
+ if (cpufreq_driver->setpolicy && cpufreq_driver->stop)
here instead? That would make it clear where the new callback belongs.
If you're fine with that, I can make that change when applying the patch.
> + cpufreq_driver->stop(policy);
> +
> return 0;
> }
>
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 4d89e0e..ff8db19 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -224,6 +224,7 @@ struct cpufreq_driver {
> int (*bios_limit) (int cpu, unsigned int *limit);
>
> int (*exit) (struct cpufreq_policy *policy);
> + int (*stop) (struct cpufreq_policy *policy);
> int (*suspend) (struct cpufreq_policy *policy);
> int (*resume) (struct cpufreq_policy *policy);
> struct freq_attr**attr;
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
From: Dirk Brandewie
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie
---
Documentation/cpu-freq/cpu-drivers.txt | 8 +++-
drivers/cpufreq/cpufreq.c | 3 +++
include/linux/cpufreq.h| 1 +
3 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/Documentation/cpu-freq/cpu-drivers.txt
b/Documentation/cpu-freq/cpu-drivers.txt
index 8b1a445..79def80 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -61,7 +61,13 @@ target_index - See below on the differences.
And optionally
-cpufreq_driver.exit - A pointer to a per-CPU cleanup function.
+cpufreq_driver.exit - A pointer to a per-CPU cleanup
+ function called during CPU_POST_DEAD
+ phase of cpu hotplug process.
+
+cpufreq_driver.stop - A pointer to a per-CPU stop function
+ called during CPU_DOWN_PREPARE phase of
+ cpu hotplug process.
cpufreq_driver.resume -A pointer to a per-CPU resume function
which is called with interrupts disabled
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cf485d9..0d430d7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
}
}
+ if (cpufreq_driver->stop)
+ cpufreq_driver->stop(policy);
+
return 0;
}
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 4d89e0e..ff8db19 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -224,6 +224,7 @@ struct cpufreq_driver {
int (*bios_limit) (int cpu, unsigned int *limit);
int (*exit) (struct cpufreq_policy *policy);
+ int (*stop) (struct cpufreq_policy *policy);
int (*suspend) (struct cpufreq_policy *policy);
int (*resume) (struct cpufreq_policy *policy);
struct freq_attr**attr;
--
1.8.3.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
From: Dirk Brandewie dirk.j.brande...@intel.com
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie dirk.j.brande...@intel.com
---
Documentation/cpu-freq/cpu-drivers.txt | 8 +++-
drivers/cpufreq/cpufreq.c | 3 +++
include/linux/cpufreq.h| 1 +
3 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/Documentation/cpu-freq/cpu-drivers.txt
b/Documentation/cpu-freq/cpu-drivers.txt
index 8b1a445..79def80 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -61,7 +61,13 @@ target_index - See below on the differences.
And optionally
-cpufreq_driver.exit - A pointer to a per-CPU cleanup function.
+cpufreq_driver.exit - A pointer to a per-CPU cleanup
+ function called during CPU_POST_DEAD
+ phase of cpu hotplug process.
+
+cpufreq_driver.stop - A pointer to a per-CPU stop function
+ called during CPU_DOWN_PREPARE phase of
+ cpu hotplug process.
cpufreq_driver.resume -A pointer to a per-CPU resume function
which is called with interrupts disabled
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cf485d9..0d430d7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
}
}
+ if (cpufreq_driver-stop)
+ cpufreq_driver-stop(policy);
+
return 0;
}
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 4d89e0e..ff8db19 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -224,6 +224,7 @@ struct cpufreq_driver {
int (*bios_limit) (int cpu, unsigned int *limit);
int (*exit) (struct cpufreq_policy *policy);
+ int (*stop) (struct cpufreq_policy *policy);
int (*suspend) (struct cpufreq_policy *policy);
int (*resume) (struct cpufreq_policy *policy);
struct freq_attr**attr;
--
1.8.3.1
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 1/2] cpufreq: Add exit_prepare callback to cpufreq_driver interface
On Friday, March 14, 2014 02:03:56 PM dirk.brande...@gmail.com wrote:
From: Dirk Brandewie dirk.j.brande...@intel.com
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie dirk.j.brande...@intel.com
---
Documentation/cpu-freq/cpu-drivers.txt | 8 +++-
drivers/cpufreq/cpufreq.c | 3 +++
include/linux/cpufreq.h| 1 +
3 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/Documentation/cpu-freq/cpu-drivers.txt
b/Documentation/cpu-freq/cpu-drivers.txt
index 8b1a445..79def80 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -61,7 +61,13 @@ target_index - See below on the
differences.
And optionally
-cpufreq_driver.exit -A pointer to a per-CPU cleanup function.
+cpufreq_driver.exit -A pointer to a per-CPU cleanup
+ function called during CPU_POST_DEAD
+ phase of cpu hotplug process.
+
+cpufreq_driver.stop -A pointer to a per-CPU stop function
+ called during CPU_DOWN_PREPARE phase of
+ cpu hotplug process.
cpufreq_driver.resume - A pointer to a per-CPU resume function
which is called with interrupts disabled
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cf485d9..0d430d7 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1338,6 +1338,9 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
}
}
+ if (cpufreq_driver-stop)
What about doing
+ if (cpufreq_driver-setpolicy cpufreq_driver-stop)
here instead? That would make it clear where the new callback belongs.
If you're fine with that, I can make that change when applying the patch.
+ cpufreq_driver-stop(policy);
+
return 0;
}
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 4d89e0e..ff8db19 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -224,6 +224,7 @@ struct cpufreq_driver {
int (*bios_limit) (int cpu, unsigned int *limit);
int (*exit) (struct cpufreq_policy *policy);
+ int (*stop) (struct cpufreq_policy *policy);
int (*suspend) (struct cpufreq_policy *policy);
int (*resume) (struct cpufreq_policy *policy);
struct freq_attr**attr;
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
