amd-pstate Dynamic EPP and raw EPP
Subsystems (3)
v2 cover amd-pstate Dynamic EPP and raw EPP
From: Mario Limonciello <[email protected]>
Dynamic EPP allows the kernel to register amd-pstate as part of a platform profile. It will change EPP modes matching the user's preference to the platform profile sysfs files as well as power adapter state.
Raw EPP allows userspace to write integers toenergy_performance_preference.
This series is based off superm1/linux.git bleeding-edge branch
v1->v2:
* Rebase
* Change some defaults
Mario Limonciello (5):
cpufreq/amd-pstate: Add dynamic energy performance preference cpufreq/amd-pstate: add kernel command line to override dynamic epp cpufreq/amd-pstate: Add support for platform profile class cpufreq/amd-pstate: Add support for raw EPP writes cpufreq/amd-pstate-ut: Add a unit test for raw EPP
.../admin-guide/kernel-parameters.txt | 7 + Documentation/admin-guide/pm/amd-pstate.rst | 41 ++- drivers/cpufreq/Kconfig.x86 | 13 + drivers/cpufreq/amd-pstate-ut.c | 58 ++++ drivers/cpufreq/amd-pstate.c | 279 ++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 16 +- 6 files changed, 390 insertions(+), 24 deletions(-)
Signature · 1 line
2.43.0
PATCH v2 1/5 cpufreq/amd-pstate: Add dynamic energy performance preference
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode is performance.
* the default EPP for DC mode is balance_performance.
---v1->v2:
* Change defaults to performance (AC) and balance_performance (DC)
* Default Kconfig to disabled for now
* Rebase on latest branch
--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)
Documentation/admin-guide/pm/amd-pstate.rst +17 -1
@@ -289,7 +289,7 @@ and user can change current preference according to energy or performance needs Please get all support profiles list from ``energy_performance_available_preferences`` attribute, all the profiles are integer values defined between 0 to 255 when EPP feature is enabled by platform -firmware, if EPP feature is disabled, driver will ignore the written value +firmware, but if the dynamic EPP feature is enabled, driver will block writes. This attribute is read-write. ``boost``
@@ -311,6 +311,22 @@ boost or `1` to enable it, for the respective CPU using the sysfs path Other performance and frequency values can be read back from ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`. +Dynamic energy performance profile +================================== +The amd-pstate driver supports dynamically selecting the energy performance +profile based on whether the machine is running on AC or DC power. + +Whether this behavior is enabled by default with the kernel config option +`CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`. This behavior can also be overridden +at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. + +When set to enabled, the driver will select a different energy performance +profile when the machine is running on battery or AC power. +When set to disabled, the driver will not change the energy performance profile +based on the power source and will not react to user desired power state. + +Attempting to manually write to the ``energy_performance_preference`` sysfs +file will fail when ``dynamic_epp`` is enabled. ``amd-pstate`` vs ``acpi-cpufreq`` ======================================
drivers/cpufreq/Kconfig.x86 +12 -0
@@ -68,6 +68,18 @@ config X86_AMD_PSTATE_DEFAULT_MODE For details, take a look at: <file:Documentation/admin-guide/pm/amd-pstate.rst>. +config X86_AMD_PSTATE_DYNAMIC_EPP + bool "AMD Processor P-State dynamic EPP support" + depends on X86_AMD_PSTATE + default n + help + Allow the kenrel to dynamically change the energy performance + value from events like ACPI platform profile and AC adapter plug + events. + + This feature can also be changed at runtime, this configuration + option only sets the kernel default value behavior. + config X86_AMD_PSTATE_UT tristate "selftest for AMD Processor P-State driver" depends on X86 && ACPI_PROCESSOR
drivers/cpufreq/amd-pstate.c +122 -7
211 lines not on this page · raw message
drivers/cpufreq/amd-pstate.h +4 -1
@@ -104,7 +104,10 @@ struct amd_cpudata {/* EPP feature related attributes*/ u32 policy;bool suspended; -u8 epp_default; +u8 epp_default_ac; +u8 epp_default_dc; +bool dynamic_epp; +struct notifier_block power_nb; };/*
Signature · 1 line
2.43.0
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Hello Mario,
Quoted 29 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)Documentation/admin-guide/pm/amd-pstate.rst +0
-0
[...snip..]
Quoted 28 lines
Documentation/admin-guide/pm/amd-pstate.rst +16
-0@@ -311,6 +311,22 @@ boost or `1` to enable it, for the respective CPU using the sysfs path Other performance and frequency values can be read back from ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`. +Dynamic energy performance profile +================================== +The amd-pstate driver supports dynamically selecting the energy performance +profile based on whether the machine is running on AC or DC power. + +Whether this behavior is enabled by default with the kernel config option +`CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`. This behavior can also be overridden +at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. + +When set to enabled, the driver will select a different energy performance +profile when the machine is running on battery or AC power. +When set to disabled, the driver will not change the energy performance profile +based on the power source and will not react to user desired power state. + +Attempting to manually write to the ``energy_performance_preference`` sysfs +file will fail when ``dynamic_epp`` is enabled. ``amd-pstate`` vs ``acpi-cpufreq`` ======================================drivers/cpufreq/Kconfig.x86 +0
-0
drivers/cpufreq/Kconfig.x86 config X86_AMD_PSTATE_DEFAULT_MODE · line 76
Quoted 9 lines
drivers/cpufreq/Kconfig.x86 +6
-0@@ -68,6 +68,18 @@ config X86_AMD_PSTATE_DEFAULT_MODE For details, take a look at: <file:Documentation/admin-guide/pm/amd-pstate.rst>. +config X86_AMD_PSTATE_DYNAMIC_EPP + bool "AMD Processor P-State dynamic EPP support" + depends on X86_AMD_PSTATE + default n + help + Allow the kenrel to dynamically change the energy performance
^^^^^^ kernel
Quoted 30 lines
drivers/cpufreq/Kconfig.x86 +6
-0+ value from events like ACPI platform profile and AC adapter plug + events. + + This feature can also be changed at runtime, this configuration + option only sets the kernel default value behavior. + config X86_AMD_PSTATE_UT tristate "selftest for AMD Processor P-State driver" depends on X86 && ACPI_PROCESSORdrivers/cpufreq/amd-pstate.c +2
-0@@ -36,6 +36,7 @@#include <linux/io.h> #include <linux/delay.h> #include <linux/uaccess.h> +#include <linux/power_supply.h> #include <linux/static_call.h> #include <linux/topology.h> @@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver;static struct cpufreq_driver amd_pstate_epp_driver;static int cppc_state =AMD_PSTATE_UNDEFINED ;static bool amd_pstate_prefcore = true; +static bool dynamic_epp =CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP ;static struct quirk_entry *quirks;/*
drivers/cpufreq/amd-pstate.c static void amd_pstate_cpu_exit(struct cpufreq_policy *policy) · line 1055
Quoted 4 lines
drivers/cpufreq/amd-pstate.c +1
-0@@ -1050,6 +1052,73 @@ static void amd_pstate_cpu_exit(struct cpufreq_policy *policy)kfree (cpudata); } +static int amd_pstate_get_balanced_epp (struct cpufreq_policy *policy)
Can we rename this function as amd_pstate_get_dynamic_epp() ?
Because the values being returned may not be
balance_performance/balance_power.
Quoted 96 lines
drivers/cpufreq/amd-pstate.c +74
-3+{ +struct amd_cpudata *cpudata = policy->driver_data; + +if (power_supply_is_system_supplied ()) +return cpudata->epp_default_ac; +else +return cpudata->epp_default_dc; +} + +static int amd_pstate_power_supply_notifier (struct notifier_block *nb, +unsigned long event,void *data) +{ + struct amd_cpudata *cpudata = container_of(nb, struct amd_cpudata, power_nb); + struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu); +u8 epp; +int ret; + +if (event !=PSY_EVENT_PROP_CHANGED ) +return NOTIFY_OK ; + + epp =amd_pstate_get_balanced_epp (policy); + + ret =amd_pstate_set_epp (policy, epp); +if (ret) +pr_warn ("Failed to set CPU %d EPP %u: %d\n" , cpudata->cpu, epp, ret); + +return NOTIFY_OK ; +} +static void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy) +{ +struct amd_cpudata *cpudata = policy->driver_data; + +if (cpudata->power_nb.notifier_call) +power_supply_unreg_notifier (&cpudata->power_nb); + cpudata->dynamic_epp = false; +} + +static int amd_pstate_set_dynamic_epp (struct cpufreq_policy *policy) +{ +struct amd_cpudata *cpudata = policy->driver_data; +int ret; +u8 epp; + + epp =amd_pstate_get_balanced_epp (policy); + ret =amd_pstate_set_epp (policy, epp); +if (ret) +return ret; + +/* only enable notifier if things will actually change */ +if (cpudata->epp_default_ac != cpudata->epp_default_dc) { + ret =power_supply_reg_notifier (&cpudata->power_nb); +if (ret) + goto cleanup; + cpudata->power_nb.notifier_call = amd_pstate_power_supply_notifier; + } + + cpudata->dynamic_epp = true; + +return 0 ; + +cleanup: +amd_pstate_clear_dynamic_epp (policy); + +return ret; +} +/* Sysfs attributes */ /* @@ -1146,6 +1215,11 @@ static ssize_t store_energy_performance_preference(ssize_t ret;u8 epp; +if (cpudata->dynamic_epp) { +pr_debug ("EPP cannot be set when dynamic EPP is enabled\n" ); +return -EBUSY ; + } + ret =sscanf (buf,"%20s" , str_preference);if (ret !=1 )return -EINVAL ;@@ -1154,10 +1228,10 @@ static ssize_t store_energy_performance_preference(if (ret <0 )return -EINVAL ; -if (!ret) - epp = cpudata->epp_default; -else +if (ret) epp = epp_values[ret]; +else + epp =amd_pstate_get_balanced_epp (policy);if (epp >0 && policy->policy ==CPUFREQ_POLICY_PERFORMANCE ) {pr_debug ("EPP cannot be set under performance policy\n" );
drivers/cpufreq/amd-pstate.c static ssize_t store_energy_performance_preference( · line 1243
Quoted 5 lines
drivers/cpufreq/amd-pstate.c +2
-0@@ -1165,6 +1239,8 @@ static ssize_t store_energy_performance_preference( } ret =amd_pstate_set_epp (policy, epp); +if (ret) +return ret;
Isn't this unecessary given that the next line is doing exactly this ?
drivers/cpufreq/amd-pstate.c static ssize_t store_energy_performance_preference( · line 1246
Quoted 3 lines
drivers/cpufreq/amd-pstate.c +0
-0return ret ? ret : count; }
Rest of the patch looks good to me.
Signature · 2 lines
Thanks and Regards gautham.
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
In reply to Mario LimoncielloQuoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)
[Snip]
Quoted 13 lines
drivers/cpufreq/amd-pstate.c +1
-0@@ -36,6 +36,7 @@#include <linux/io.h> #include <linux/delay.h> #include <linux/uaccess.h> +#include <linux/power_supply.h> #include <linux/static_call.h> #include <linux/topology.h>
drivers/cpufreq/amd-pstate.c static struct cpufreq_driver amd_pstate_driver; · line 90
Quoted 4 lines
drivers/cpufreq/amd-pstate.c +1
-0@@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver;static struct cpufreq_driver amd_pstate_epp_driver;static int cppc_state =AMD_PSTATE_UNDEFINED ;static bool amd_pstate_prefcore = true; +static bool dynamic_epp =CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP ;
Is there an #ifdef needed here? I see build error when X86_AMD_PSTATE_DYNAMIC_EPP is not set in config
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Quoted 39 lines · Dhananjay Ugwekar
Quoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)[Snip]
Quoted 12 lines
drivers/cpufreq/amd-pstate.c +1
-0@@ -36,6 +36,7 @@#include <linux/io.h> #include <linux/delay.h> #include <linux/uaccess.h> +#include <linux/power_supply.h> #include <linux/static_call.h> #include <linux/topology.h>
Quoted 8 lines
drivers/cpufreq/amd-pstate.c static struct cpufreq_driver amd_pstate_driver; · line 90
Quoted 5 lines
drivers/cpufreq/amd-pstate.c +1
-0@@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver;static struct cpufreq_driver amd_pstate_epp_driver;static int cppc_state =AMD_PSTATE_UNDEFINED ;static bool amd_pstate_prefcore = true; +static bool dynamic_epp =CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP ;Is there an #ifdef needed here? I see build error when
X86_AMD_PSTATE_DYNAMIC_EPPis not set in config
Ah yeah, I see the same too when I check that config. Not sure why build robot didn't catch this.
Will add this for next version.
drivers/cpufreq/amd-pstate.c +4 -0
@@ -87,7 +87,11 @@ static struct cpufreq_driver amd_pstate_driver;static struct cpufreq_driver amd_pstate_epp_driver;static int cppc_state =AMD_PSTATE_UNDEFINED ;static bool amd_pstate_prefcore = true; +#ifdef CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP static bool dynamic_epp =CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP ; +#else +static bool dynamic_epp = false; +#endif static struct quirk_entry *quirks;/*
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
In reply to Mario LimoncielloQuoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)
[Snip]
drivers/cpufreq/amd-pstate.c static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) · line 1672
Quoted 7 lines
drivers/cpufreq/amd-pstate.c +3
-0@@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)if (!policy->cpuinfo.max_freq)return -ENODEV ; +/* policy can't be changed to performance policy while dynamic epp is enabled */ +if (policy->policy ==CPUFREQ_POLICY_PERFORMANCE && cpudata->dynamic_epp) +return -EBUSY ;
We might need to tweak this condition, because if we enable "CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()->amd_pstate_epp_set_policy()) driver init fails as the default governor is performance.
Quoted 20 lines
drivers/cpufreq/amd-pstate.c +1
-0+ cpudata->policy = policy->policy; ret =amd_pstate_epp_update_limit (policy);drivers/cpufreq/amd-pstate.h +4
-1@@ -104,7 +104,10 @@ struct amd_cpudata {/* EPP feature related attributes*/ u32 policy;bool suspended; -u8 epp_default; +u8 epp_default_ac; +u8 epp_default_dc; +bool dynamic_epp; +struct notifier_block power_nb; };/*
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Quoted 31 lines · Dhananjay Ugwekar
Quoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)[Snip]
Quoted 4 lines
(quoted diff) +0
-0@@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) if (!policy->cpuinfo.max_freq) return -ENODEV;
Quoted 8 lines
Review static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) · line 1672
Quoted 3 lines
(quoted diff) +3
-0+ /* policy can't be changed to performance policy while dynamic epp is enabled */ + if (policy->policy == CPUFREQ_POLICY_PERFORMANCE && cpudata->dynamic_epp) + return -EBUSY;We might need to tweak this condition, because if we enable "
CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()->amd_pstate_epp_set_policy()) driver init fails as the default governor is performance.
The check is important to make sure that you can't go to performance mode after init.
I think this is the way I would want to solve it.
Set policy to powersave before enabling dynamic epp for amd_pstate_epp_cpu_init().
drivers/cpufreq/amd-pstate.c +3 -1
@@ -1729,8 +1729,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)WRITE_ONCE (cpudata->cppc_req_cached, value); } -if (dynamic_epp) +if (dynamic_epp) { + policy->policy =CPUFREQ_POLICY_POWERSAVE ; ret =amd_pstate_set_dynamic_epp (policy); + }else ret = amd_pstate_set_epp(policy,
amd_pstate_get_balanced_epp(policy));
if (ret)
Thoughts?
Quoted 21 lines
Quoted 20 lines
(quoted diff) +1
-0+ cpudata->policy = policy->policy; ret = amd_pstate_epp_update_limit(policy);drivers/cpufreq/amd-pstate.h +4
-1@@ -104,7 +104,10 @@ struct amd_cpudata {/* EPP feature related attributes*/ u32 policy;bool suspended; -u8 epp_default; +u8 epp_default_ac; +u8 epp_default_dc; +bool dynamic_epp; +struct notifier_block power_nb; };/*
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Quoted 58 lines · Mario Limonciello
Quoted 27 lines · Dhananjay Ugwekar
Quoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch
---
Documentation/admin-guide/pm/amd-pstate.rst| 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +-4 files changed, 155 insertions(+), 9 deletions(-)[Snip]
Quoted 11 lines
Quoted 6 lines
(quoted diff) +0
-0@@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) if (!policy->cpuinfo.max_freq) return -ENODEV;+ /* policy can't be changed to performance policy while dynamic epp is enabled */ + if (
policy->policy==CPUFREQ_POLICY_PERFORMANCE&&cpudata->dynamic_epp) + return-EBUSY;We might need to tweak this condition, because if we enable "
CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()->amd_pstate_epp_set_policy()) driver init fails as the default governor is performance.The check is important to make sure that you can't go to performance mode after init.
I think this is the way I would want to solve it.
Set policy to powersave before enabling dynamic epp foramd_pstate_epp_cpu_init().drivers/cpufreq/amd-pstate.c +3
-1@@ -1729,8 +1729,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) WRITE_ONCE(cpudata->cppc_req_cached, value); } - if (dynamic_epp) + if (dynamic_epp) { + policy->policy = CPUFREQ_POLICY_POWERSAVE; ret = amd_pstate_set_dynamic_epp(policy); + }
Quoted 2 lines
else
ret =amd_pstate_set_epp(policy, amd_pstate_get_balanced_epp(policy));
^^^^^^^^^^^^ (mentioned below)
Quoted 3 lines
if (ret)
Thoughts?
Yes, this looks good, because anyway there is no point in having performance governor and dynamic epp set at the same time.
I found one related quirk though, we are setting performance governor for server platforms in amd_pstate_epp_cpu_init() and then setting epp at the line highlighted above. We dont have a check in *_set_epp() functions for performance governor. This could alter the performance governor behavior if we set a "balanced" epp for it. I haven't tested this part yet.
Thanks,
Dhananjay
Quoted 21 lines
Quoted 20 lines
Quoted 19 lines
+
cpudata->policy=policy->policy; ret =amd_pstate_epp_update_limit(policy);drivers/cpufreq/amd-pstate.h +4
-1@@ -104,7 +104,10 @@ struct amd_cpudata { /* EPP feature related attributes*/ u32 policy; bool suspended; - u8 epp_default; + u8 epp_default_ac; + u8 epp_default_dc; + bool dynamic_epp; + struct notifier_block power_nb; }; /*
Re: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Quoted 66 lines · Dhananjay Ugwekar
Quoted 50 lines · Mario Limonciello
Quoted 27 lines · Dhananjay Ugwekar
Quoted 25 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch--- Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- drivers/cpufreq/amd-pstate.h | 5 +- 4 files changed, 155 insertions(+), 9 deletions(-)[Snip]
Quoted 11 lines
Review static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) · line 1671
Quoted 6 lines
(quoted diff) +2
-0@@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) if (!policy->cpuinfo.max_freq) return -ENODEV; + /* policy can't be changed to performance policy while dynamic epp is enabled */ + if (policy->policy == CPUFREQ_POLICY_PERFORMANCE && cpudata->dynamic_epp) + return -EBUSY;We might need to tweak this condition, because if we enable "
CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()->amd_pstate_epp_set_policy()) driver init fails as the default governor is performance.The check is important to make sure that you can't go to performance mode after init.
I think this is the way I would want to solve it.
Set policy to powersave before enabling dynamic epp foramd_pstate_epp_cpu_init().drivers/cpufreq/amd-pstate.c +0
-0drivers/cpufreq/amd-pstate.c static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) · line 1737
Quoted 10 lines
drivers/cpufreq/amd-pstate.c +3
-1@@ -1729,8 +1729,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) WRITE_ONCE(cpudata->cppc_req_cached, value); } - if (dynamic_epp) + if (dynamic_epp) { + policy->policy = CPUFREQ_POLICY_POWERSAVE; ret = amd_pstate_set_dynamic_epp(policy); + } else ret = amd_pstate_set_epp(policy, amd_pstate_get_balanced_epp(policy));^^^^^^^^^^^^ (mentioned below)Quoted 3 lines
drivers/cpufreq/amd-pstate.c +0
-0if (ret)Thoughts?
Quoted 7 lines
Yes, this looks good, because anyway there is no point in having performance governor and dynamic epp set at the same time.
I found one related quirk though, we are setting performance governor for server platforms in
amd_pstate_epp_cpu_init()and then setting epp at the line highlighted above. We dont have a check in*_set_epp()functions for performance governor. This could alter the performance governor behavior if we set a "balanced" epp for it. I haven't tested this part yet.
In that case we probably want the "default" ACPI platform profile to be "performance" when on a server instead of balanced.
Quoted 26 lines
Thanks,
DhananjayQuoted 21 lines
Quoted 20 lines
Quoted 19 lines
(quoted diff) +1
-0+ cpudata->policy = policy->policy; ret = amd_pstate_epp_update_limit(policy);drivers/cpufreq/amd-pstate.h +4
-1@@ -104,7 +104,10 @@ struct amd_cpudata { /* EPP feature related attributes*/ u32 policy; bool suspended; - u8 epp_default; + u8 epp_default_ac; + u8 epp_default_dc; + bool dynamic_epp; + struct notifier_block power_nb; }; /*
Mario Limonciello
maintainerRe: [PATCH v2 1/5] cpufreq/amd-pstate: Add dynamic energy performance preference
Quoted 75 lines · Mario Limonciello
Quoted 74 lines · Dhananjay Ugwekar
Quoted 63 lines · Mario Limonciello
Quoted 34 lines · Dhananjay Ugwekar
Quoted 26 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Dynamic energy performance preference will change the EPP profile based on whether the machine is running on AC or DC power.
A notification chain from the power supply core is used to adjust EPP values on plug in or plug out events.
For non-server systems:
* the default EPP for AC mode isperformance.
* the default EPP for DC mode isbalance_performance.Signed-off-by Mario Limonciello <[email protected]>---
v1->v2:
* Change defaults to performance (AC) andbalance_performance(DC)
* DefaultKconfigto disabled for now
* Rebase on latest branch
---
Documentation/admin-guide/pm/amd-pstate.rst| 18 ++- drivers/cpufreq/Kconfig.x86 | 12 ++ drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++
++++--
drivers/cpufreq/amd-pstate.h | 5 +-4 files changed, 155 insertions(+), 9 deletions(-)[Snip]
Quoted 6 lines
(quoted diff) +0
-0@@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) if (!policy->cpuinfo.max_freq) return -ENODEV;+ /* policy can't be changed to performance policy while dynamic epp is enabled */ + if (
policy->policy==CPUFREQ_POLICY_PERFORMANCE&& cpudata-Quoted 8 lines
Quoted 2 lines
Quoted 1 line
dynamic_epp)+ return
-EBUSY;We might need to tweak this condition, because if we enable "
CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()-Quoted 1 line
amd_pstate_epp_set_policy()) driver init failsas the default governor is performance.
The check is important to make sure that you can't go to performance mode after init.
I think this is the way I would want to solve it.
Set policy to powersave before enabling dynamic epp foramd_pstate_epp_cpu_init().drivers/cpufreq/amd-pstate.c +3
-1@@ -1729,8 +1729,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) WRITE_ONCE(cpudata->cppc_req_cached, value); } - if (dynamic_epp) + if (dynamic_epp) { + policy->policy = CPUFREQ_POLICY_POWERSAVE; ret = amd_pstate_set_dynamic_epp(policy); + }Quoted 2 lines
else
ret =amd_pstate_set_epp(policy, amd_pstate_get_balanced_epp(policy));^^^^^^^^^^^^ (mentioned below)
Quoted 3 lines
if (ret)
Thoughts?
Yes, this looks good, because anyway there is no point in having performance governor and dynamic epp set at the same time.
Quoted 6 lines
Quoted 4 lines
I found one related quirk though, we are setting performance governor for server platforms in
amd_pstate_epp_cpu_init()and then setting epp at the line highlighted above. We dont have a check in*_set_epp()functions for performance governor. This could alter the performance governor behavior if we set a "balanced" epp for it. I haven't tested this part yet.In that case we probably want the "default" ACPI platform profile to be "performance" when on a server instead of balanced.
Actually this is already done:
cpudata->current_profile = PLATFORM_PROFILE_PERFORMANCE;
I'll post an updated patch series for you to test.
Quoted 28 lines
Quoted 27 lines
Thanks,
DhananjayQuoted 21 lines
Quoted 20 lines
Quoted 19 lines
+
cpudata->policy=policy->policy; ret =amd_pstate_epp_update_limit(policy);drivers/cpufreq/amd-pstate.h +4
-1@@ -104,7 +104,10 @@ struct amd_cpudata { /* EPP feature related attributes*/ u32 policy; bool suspended; - u8 epp_default; + u8 epp_default_ac; + u8 epp_default_dc; + bool dynamic_epp; + struct notifier_block power_nb; }; /*
PATCH v2 2/5 cpufreq/amd-pstate: add kernel command line to override dynamic epp
In reply to Mario LimoncielloFrom: Mario Limonciello <[email protected]>
Add amd_dynamic_epp=enable and amd_dynamic_epp=disable to override the kernel configuration option CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP locally.
--- Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ Documentation/admin-guide/pm/amd-pstate.rst | 7 +++++++ drivers/cpufreq/amd-pstate.c | 11 +++++++++++ 3 files changed, 25 insertions(+)
Documentation/admin-guide/kernel-parameters.txt +7 -0
@@ -392,6 +392,13 @@ disable Disable amd-pstate preferred core. + amd_dynamic_epp= + [X86] + disable + Disable amd-pstate dynamic EPP. + enable + Enable amd-pstate dynamic EPP. + amijoy.map= [HW,JOY] Amiga joystick support Map of devices attached to JOY0DAT and JOY1DAT Format: <a>,<b>
Documentation/admin-guide/pm/amd-pstate.rst +7 -0
@@ -438,6 +438,13 @@ For systems that support ``amd-pstate`` preferred core, the core rankings will always be advertised by the platform. But OS can choose to ignore that via the kernel parameter ``amd_prefcore=disable``. +``amd_dynamic_epp`` + +When AMD pstate is in auto mode, dynamic EPP will control whether the kernel +autonomously changes the EPP mode. The default is configured by +``CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`` but can be explicitly enabled with +``amd_pstate_epp=enable`` or disabled with ``amd_pstate_epp=disable``. + User Space Interface in ``sysfs`` - General ===========================================
drivers/cpufreq/amd-pstate.c +11 -0
@@ -1928,8 +1928,19 @@ static int __init amd_prefcore_param(char *str)return 0 ; } +static int __init amd_dynamic_epp_param (char *str) +{ +if (!strcmp (str,"disable" )) + dynamic_epp = false; +if (!strcmp (str,"enable" )) + dynamic_epp = true; + +return 0 ; +} +early_param ("amd_pstate" , amd_pstate_param);early_param ("amd_prefcore" , amd_prefcore_param); +early_param ("amd_dynamic_epp" , amd_dynamic_epp_param);MODULE_AUTHOR ("Huang Rui <[email protected]>" );MODULE_DESCRIPTION ("AMD Processor P-state Frequency Driver" );
Signature · 1 line
2.43.0
Re: [PATCH v2 2/5] cpufreq/amd-pstate: add kernel command line to override dynamic epp
Quoted 5 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
Add
amd_dynamic_epp=enableandamd_dynamic_epp=disableto override the kernel configuration optionCONFIG_X86_AMD_PSTATE_DYNAMIC_EPPlocally.
Even with this patch, the user can switch the dynamic_epp value via the sysfs file. However, it is useful in case the CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP value is switched in the future.
I suspect that the servers will prefer to have this feature disabled by default (they are always on AC power!) while the laptop/battery operated devices would prefer to have this option enabled by default.
Signature · 2 lines
Thanks and Regards gautham.
Quoted 71 lines
Signed-off-by Mario Limonciello <[email protected]>--- Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ Documentation/admin-guide/pm/amd-pstate.rst | 7 +++++++ drivers/cpufreq/amd-pstate.c | 11 +++++++++++ 3 files changed, 25 insertions(+)Documentation/admin-guide/kernel-parameters.txt +7
-0@@ -392,6 +392,13 @@ disable Disable amd-pstate preferred core. + amd_dynamic_epp= + [X86] + disable + Disable amd-pstate dynamic EPP. + enable + Enable amd-pstate dynamic EPP. + amijoy.map= [HW,JOY] Amiga joystick support Map of devices attached to JOY0DAT and JOY1DAT Format: <a>,<b>Documentation/admin-guide/pm/amd-pstate.rst +7
-0@@ -438,6 +438,13 @@ For systems that support ``amd-pstate`` preferred core, the core rankings will always be advertised by the platform. But OS can choose to ignore that via the kernel parameter ``amd_prefcore=disable``. +``amd_dynamic_epp`` + +When AMD pstate is in auto mode, dynamic EPP will control whether the kernel +autonomously changes the EPP mode. The default is configured by +``CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`` but can be explicitly enabled with +``amd_pstate_epp=enable`` or disabled with ``amd_pstate_epp=disable``. + User Space Interface in ``sysfs`` - General ===========================================drivers/cpufreq/amd-pstate.c +11
-0@@ -1928,8 +1928,19 @@ static int __init amd_prefcore_param(char *str)return 0 ; } +static int __init amd_dynamic_epp_param (char *str) +{ +if (!strcmp (str,"disable" )) + dynamic_epp = false; +if (!strcmp (str,"enable" )) + dynamic_epp = true; + +return 0 ; +} +early_param ("amd_pstate" , amd_pstate_param);early_param ("amd_prefcore" , amd_prefcore_param); +early_param ("amd_dynamic_epp" , amd_dynamic_epp_param);MODULE_AUTHOR ("Huang Rui <[email protected]>" );MODULE_DESCRIPTION ("AMD Processor P-state Frequency Driver" );Signature · 1 line
2.43.0
PATCH v2 3/5 cpufreq/amd-pstate: Add support for platform profile class
In reply to Mario LimoncielloFrom: Mario Limonciello <[email protected]>
The platform profile core allows multiple drivers and devices to register platform profile support.
When the legacy platform profile interface is used all drivers will adjust the platform profile as well.
Add support for registering every CPU with the platform profile handler when dynamic EPP is enabled.
The end result will be that changing the platform profile will modify EPP accordingly.
--- Documentation/admin-guide/pm/amd-pstate.rst | 4 +- drivers/cpufreq/Kconfig.x86 | 1 + drivers/cpufreq/amd-pstate.c | 142 +++++++++++++++++--- drivers/cpufreq/amd-pstate.h | 10 ++ 4 files changed, 140 insertions(+), 17 deletions(-)
Documentation/admin-guide/pm/amd-pstate.rst +3 -1
@@ -321,7 +321,9 @@ Whether this behavior is enabled by default with the kernel config option at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. When set to enabled, the driver will select a different energy performance -profile when the machine is running on battery or AC power. +profile when the machine is running on battery or AC power. The driver will +also register with the platform profile handler to receive notifications of +user desired power state and react to those. When set to disabled, the driver will not change the energy performance profile based on the power source and will not react to user desired power state.
drivers/cpufreq/Kconfig.x86 +1 -0
@@ -40,6 +40,7 @@ config X86_AMD_PSTATE select ACPI_PROCESSOR select ACPI_CPPC_LIB if X86_64 select CPU_FREQ_GOV_SCHEDUTIL if SMP + select ACPI_PLATFORM_PROFILE help This driver adds a CPUFreq driver which utilizes a fine grain processor performance frequency control range instead of legacy
drivers/cpufreq/amd-pstate.c +126 -16
229 lines not on this page · raw message
drivers/cpufreq/amd-pstate.h +10 -0
@@ -9,6 +9,7 @@#define _LINUX_AMD_PSTATE_H#include <linux/pm_qos.h> +#include <linux/platform_profile.h> /********************************************************************* * AMD P-state INTERFACE *
@@ -108,6 +109,11 @@ struct amd_cpudata {u8 epp_default_dc;bool dynamic_epp;struct notifier_block power_nb; + +/* platform profile */ +enum platform_profile_option current_profile; +struct device *ppdev; +char *profile_name; };/*
@@ -123,5 +129,9 @@ enum amd_pstate_mode { };const char *amd_pstate_get_mode_string (enum amd_pstate_mode mode);int amd_pstate_update_status (const char *buf,size_t size); +ssize_t store_energy_performance_preference (struct cpufreq_policy *policy, +const char *buf,size_t count); +ssize_t show_energy_performance_preference (struct cpufreq_policy *policy,char *buf); +void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy);#endif /* _LINUX_AMD_PSTATE_H */
Signature · 1 line
2.43.0
Re: [PATCH v2 3/5] cpufreq/amd-pstate: Add support for platform profile class
Quoted 114 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
The platform profile core allows multiple drivers and devices to register platform profile support.
When the legacy platform profile interface is used all drivers will adjust the platform profile as well.
Add support for registering every CPU with the platform profile handler when dynamic EPP is enabled.
The end result will be that changing the platform profile will modify EPP accordingly.
Signed-off-by Mario Limonciello <[email protected]>--- Documentation/admin-guide/pm/amd-pstate.rst | 4 +- drivers/cpufreq/Kconfig.x86 | 1 + drivers/cpufreq/amd-pstate.c | 142 +++++++++++++++++--- drivers/cpufreq/amd-pstate.h | 10 ++ 4 files changed, 140 insertions(+), 17 deletions(-)Documentation/admin-guide/pm/amd-pstate.rst +3
-1@@ -321,7 +321,9 @@ Whether this behavior is enabled by default with the kernel config option at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. When set to enabled, the driver will select a different energy performance -profile when the machine is running on battery or AC power. +profile when the machine is running on battery or AC power. The driver will +also register with the platform profile handler to receive notifications of +user desired power state and react to those. When set to disabled, the driver will not change the energy performance profile based on the power source and will not react to user desired power state.drivers/cpufreq/Kconfig.x86 +1
-0@@ -40,6 +40,7 @@ config X86_AMD_PSTATE select ACPI_PROCESSOR select ACPI_CPPC_LIB if X86_64 select CPU_FREQ_GOV_SCHEDUTIL if SMP + select ACPI_PLATFORM_PROFILE help This driver adds a CPUFreq driver which utilizes a fine grain processor performance frequency control range instead of legacydrivers/cpufreq/amd-pstate.c +28
-1@@ -105,6 +105,7 @@ static struct quirk_entry *quirks;* 2 balance_performance * 3 balance_power * 4 power +* 5 custom (for raw EPP values) */ enum energy_perf_value_index {EPP_INDEX_DEFAULT =0 ,@@ -112,6 +113,7 @@ enum energy_perf_value_index {EPP_INDEX_BALANCE_PERFORMANCE ,EPP_INDEX_BALANCE_POWERSAVE ,EPP_INDEX_POWERSAVE , + EPP_INDEX_CUSTOM, }; static const char * const energy_perf_strings[] = {@@ -120,6 +122,7 @@ static const char * const energy_perf_strings[] = { [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance", [EPP_INDEX_BALANCE_POWERSAVE] = "balance_power", [EPP_INDEX_POWERSAVE] = "power", + [EPP_INDEX_CUSTOM ] ="custom" , NULL };@@ -1073,6 +1076,10 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb,if (event !=PSY_EVENT_PROP_CHANGED )return NOTIFY_OK ; +/* dynamic actions are only applied while platform profile is in balanced */ +if (cpudata->current_profile !=PLATFORM_PROFILE_BALANCED ) +return 0 ; + epp =amd_pstate_get_balanced_epp (policy); ret =amd_pstate_set_epp (policy, epp);@@ -1081,14 +1088,84 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb,return NOTIFY_OK ; } -static void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy) + +static int amd_pstate_profile_probe (void *drvdata,unsigned long *choices) +{ +set_bit (PLATFORM_PROFILE_LOW_POWER , choices); +set_bit (PLATFORM_PROFILE_BALANCED , choices); +set_bit (PLATFORM_PROFILE_PERFORMANCE , choices); + +return 0 ; +} + +static int amd_pstate_profile_get (struct device *dev, +enum platform_profile_option *profile) +{ +struct amd_cpudata *cpudata =dev_get_drvdata (dev); + + *profile = cpudata->current_profile; + +return 0 ; +} + +static int amd_pstate_profile_set(struct device *dev,
drivers/cpufreq/amd-pstate.c static int amd_pstate_power_supply_notifier(struct notifier_block *nb, · line 1121
Quoted 10 lines
drivers/cpufreq/amd-pstate.c +10
-0+ enum platform_profile_option profile) +{ +struct amd_cpudata *cpudata =dev_get_drvdata (dev); + struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu); +int ret; + +switch (profile) { +case PLATFORM_PROFILE_LOW_POWER : +if (cpudata->policy !=CPUFREQ_POLICY_POWERSAVE ) + cpudata->policy =CPUFREQ_POLICY_POWERSAVE ;
So prior to the patch, cpudata->policy is supposed to mirror policy->policy. With this patch, this assumption is no longer true. So it is possible for the user to again override the choice of EPP set via platform profile by changing the cpufreq governor ?
Is this the expected behaviour?
The bigger concern is, if the governor was previously "performance" and then the platform profile requested "low power", "cat /sys/devices/system/cpu/cpuX/cpufreq/scaling_governor" would still show "performance", which is inconsistent with the behaviour.
Signature · 2 lines
Thanks and Regards gautham.
Quoted 206 lines
drivers/cpufreq/amd-pstate.c +88
-15+ ret =amd_pstate_set_epp (policy,AMD_CPPC_EPP_POWERSAVE ); +if (ret) +return ret; +break ; +case PLATFORM_PROFILE_BALANCED : +if (cpudata->policy !=CPUFREQ_POLICY_POWERSAVE ) + cpudata->policy =CPUFREQ_POLICY_POWERSAVE ; + ret =amd_pstate_set_epp (policy, +amd_pstate_get_balanced_epp (policy)); +if (ret) +return ret; +break ; +case PLATFORM_PROFILE_PERFORMANCE : + ret =amd_pstate_set_epp (policy,AMD_CPPC_EPP_PERFORMANCE ); +if (ret) +return ret; +break ; +default : +pr_err ("Unknown Platform Profile %d\n" , profile); +return -EOPNOTSUPP ; + } + + cpudata->current_profile = profile; + +return 0 ; +} + +static const struct platform_profile_ops amd_pstate_profile_ops = { + .probe = amd_pstate_profile_probe, + .profile_set = amd_pstate_profile_set, + .profile_get = amd_pstate_profile_get, +}; + +void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy) {struct amd_cpudata *cpudata = policy->driver_data;if (cpudata->power_nb.notifier_call)power_supply_unreg_notifier (&cpudata->power_nb); +if (cpudata->ppdev) { +platform_profile_remove (cpudata->ppdev); + cpudata->ppdev =NULL ; + } +kfree (cpudata->profile_name); cpudata->dynamic_epp = false; } +EXPORT_SYMBOL_GPL (amd_pstate_clear_dynamic_epp);static int amd_pstate_set_dynamic_epp (struct cpufreq_policy *policy) {@@ -1096,11 +1173,35 @@ static int amd_pstate_set_dynamic_epp(struct cpufreq_policy *policy)int ret;u8 epp; - epp =amd_pstate_get_balanced_epp (policy); +switch (cpudata->current_profile) { +case PLATFORM_PROFILE_PERFORMANCE : + epp =AMD_CPPC_EPP_PERFORMANCE ; +break ; +case PLATFORM_PROFILE_LOW_POWER : + epp =AMD_CPPC_EPP_POWERSAVE ; +break ; +case PLATFORM_PROFILE_BALANCED : + epp =amd_pstate_get_balanced_epp (policy); +break ; +default : +pr_err ("Unknown Platform Profile %d\n" , cpudata->current_profile); +return -EOPNOTSUPP ; + } ret =amd_pstate_set_epp (policy, epp);if (ret)return ret; + cpudata->profile_name =kasprintf (GFP_KERNEL ,"amd-pstate-epp-cpu%d" , cpudata->cpu); + + cpudata->ppdev =platform_profile_register (get_cpu_device (policy->cpu), + cpudata->profile_name, + policy->driver_data, + &amd_pstate_profile_ops); +if (IS_ERR (cpudata->ppdev)) { + ret =PTR_ERR (cpudata->ppdev); + goto cleanup; + } +/* only enable notifier if things will actually change */ if (cpudata->epp_default_ac != cpudata->epp_default_dc) { ret =power_supply_reg_notifier (&cpudata->power_nb);@@ -1207,8 +1308,8 @@ static ssize_t show_energy_performance_available_preferences(return offset; } -static ssize_t store_energy_performance_preference ( -struct cpufreq_policy *policy,const char *buf,size_t count) +ssize_t store_energy_performance_preference (struct cpufreq_policy *policy, +const char *buf,size_t count) {struct amd_cpudata *cpudata = policy->driver_data;char str_preference[21 ];@@ -1224,16 +1325,22 @@ static ssize_t store_energy_performance_preference(if (ret !=1 )return -EINVAL ; - ret =match_string (energy_perf_strings,-1 , str_preference); -if (ret <0 ) -return -EINVAL ; - -if (ret) - epp = epp_values[ret]; -else - epp =amd_pstate_get_balanced_epp (policy); +/* +* if the value matches a number, use that, otherwise see if +* matches an index in the energy_perf_strings array +*/ + ret =kstrtou8 (str_preference,0 , &epp); +if (ret) { + ret =match_string (energy_perf_strings,-1 , str_preference); +if (ret <0 || ret ==EPP_INDEX_CUSTOM ) +return -EINVAL ; +if (ret) + epp = epp_values[ret]; +else + epp =amd_pstate_get_balanced_epp (policy); + } -if (epp >0 && policy->policy ==CPUFREQ_POLICY_PERFORMANCE ) { +if (epp >0 && cpudata->policy ==CPUFREQ_POLICY_PERFORMANCE ) {pr_debug ("EPP cannot be set under performance policy\n" );return -EBUSY ; }@@ -1244,9 +1351,9 @@ static ssize_t store_energy_performance_preference(return ret ? ret : count; } +EXPORT_SYMBOL_GPL (store_energy_performance_preference); -static ssize_t show_energy_performance_preference ( -struct cpufreq_policy *policy,char *buf) +ssize_t show_energy_performance_preference (struct cpufreq_policy *policy,char *buf) {struct amd_cpudata *cpudata = policy->driver_data;u8 preference, epp;@@ -1267,11 +1374,12 @@ static ssize_t show_energy_performance_preference( preference =EPP_INDEX_POWERSAVE ;break ;default : -return -EINVAL ; +return sysfs_emit (buf,"%u\n" , epp); }return sysfs_emit (buf,"%s\n" , energy_perf_strings[preference]); } +EXPORT_SYMBOL_GPL (show_energy_performance_preference);static void amd_pstate_driver_cleanup (void ) {@@ -1595,10 +1703,12 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) amd_pstate_acpi_pm_profile_undefined()) { policy->policy = CPUFREQ_POLICY_PERFORMANCE; cpudata->epp_default_ac = cpudata->epp_default_dc = amd_pstate_get_epp(cpudata); + cpudata->current_profile = PLATFORM_PROFILE_PERFORMANCE; } else { policy->policy =CPUFREQ_POLICY_POWERSAVE ; cpudata->epp_default_ac =AMD_CPPC_EPP_PERFORMANCE ; cpudata->epp_default_dc =AMD_CPPC_EPP_BALANCE_PERFORMANCE ; + cpudata->current_profile =PLATFORM_PROFILE_BALANCED ; }if (cpu_feature_enabled (X86_FEATURE_CPPC )) {drivers/cpufreq/amd-pstate.h +10
-0@@ -9,6 +9,7 @@#define _LINUX_AMD_PSTATE_H#include <linux/pm_qos.h> +#include <linux/platform_profile.h> /********************************************************************* * AMD P-state INTERFACE * @@ -108,6 +109,11 @@ struct amd_cpudata {u8 epp_default_dc;bool dynamic_epp;struct notifier_block power_nb; + +/* platform profile */ +enum platform_profile_option current_profile; +struct device *ppdev; +char *profile_name; };/* @@ -123,5 +129,9 @@ enum amd_pstate_mode { };const char *amd_pstate_get_mode_string (enum amd_pstate_mode mode);int amd_pstate_update_status (const char *buf,size_t size); +ssize_t store_energy_performance_preference (struct cpufreq_policy *policy, +const char *buf,size_t count); +ssize_t show_energy_performance_preference (struct cpufreq_policy *policy,char *buf); +void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy);#endif /* _LINUX_AMD_PSTATE_H */ Signature · 1 line
2.43.0
Re: [PATCH v2 3/5] cpufreq/amd-pstate: Add support for platform profile class
Quoted 131 lines · Gautham R. Shenoy
Quoted 114 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
The platform profile core allows multiple drivers and devices to register platform profile support.
When the legacy platform profile interface is used all drivers will adjust the platform profile as well.
Add support for registering every CPU with the platform profile handler when dynamic EPP is enabled.
The end result will be that changing the platform profile will modify EPP accordingly.
Signed-off-by Mario Limonciello <[email protected]>--- Documentation/admin-guide/pm/amd-pstate.rst | 4 +- drivers/cpufreq/Kconfig.x86 | 1 + drivers/cpufreq/amd-pstate.c | 142 +++++++++++++++++--- drivers/cpufreq/amd-pstate.h | 10 ++ 4 files changed, 140 insertions(+), 17 deletions(-)Documentation/admin-guide/pm/amd-pstate.rst +3
-1@@ -321,7 +321,9 @@ Whether this behavior is enabled by default with the kernel config option at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. When set to enabled, the driver will select a different energy performance -profile when the machine is running on battery or AC power. +profile when the machine is running on battery or AC power. The driver will +also register with the platform profile handler to receive notifications of +user desired power state and react to those. When set to disabled, the driver will not change the energy performance profile based on the power source and will not react to user desired power state.drivers/cpufreq/Kconfig.x86 +1
-0@@ -40,6 +40,7 @@ config X86_AMD_PSTATE select ACPI_PROCESSOR select ACPI_CPPC_LIB if X86_64 select CPU_FREQ_GOV_SCHEDUTIL if SMP + select ACPI_PLATFORM_PROFILE help This driver adds a CPUFreq driver which utilizes a fine grain processor performance frequency control range instead of legacydrivers/cpufreq/amd-pstate.c +28
-1@@ -105,6 +105,7 @@ static struct quirk_entry *quirks;* 2 balance_performance * 3 balance_power * 4 power +* 5 custom (for raw EPP values) */ enum energy_perf_value_index {EPP_INDEX_DEFAULT =0 ,@@ -112,6 +113,7 @@ enum energy_perf_value_index {EPP_INDEX_BALANCE_PERFORMANCE ,EPP_INDEX_BALANCE_POWERSAVE ,EPP_INDEX_POWERSAVE , + EPP_INDEX_CUSTOM, }; static const char * const energy_perf_strings[] = {@@ -120,6 +122,7 @@ static const char * const energy_perf_strings[] = { [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance", [EPP_INDEX_BALANCE_POWERSAVE] = "balance_power", [EPP_INDEX_POWERSAVE] = "power", + [EPP_INDEX_CUSTOM ] ="custom" , NULL };@@ -1073,6 +1076,10 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb,if (event !=PSY_EVENT_PROP_CHANGED )return NOTIFY_OK ; +/* dynamic actions are only applied while platform profile is in balanced */ +if (cpudata->current_profile !=PLATFORM_PROFILE_BALANCED ) +return 0 ; + epp =amd_pstate_get_balanced_epp (policy); ret =amd_pstate_set_epp (policy, epp);@@ -1081,14 +1088,84 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb,return NOTIFY_OK ; } -static void amd_pstate_clear_dynamic_epp (struct cpufreq_policy *policy) + +static int amd_pstate_profile_probe (void *drvdata,unsigned long *choices) +{ +set_bit (PLATFORM_PROFILE_LOW_POWER , choices); +set_bit (PLATFORM_PROFILE_BALANCED , choices); +set_bit (PLATFORM_PROFILE_PERFORMANCE , choices); + +return 0 ; +} + +static int amd_pstate_profile_get (struct device *dev, +enum platform_profile_option *profile) +{ +struct amd_cpudata *cpudata =dev_get_drvdata (dev); + + *profile = cpudata->current_profile; + +return 0 ; +} + +static int amd_pstate_profile_set(struct device *dev,drivers/cpufreq/amd-pstate.c static int amd_pstate_power_supply_notifier(struct notifier_block *nb, · line 1121
Quoted 10 lines
drivers/cpufreq/amd-pstate.c +10
-0+ enum platform_profile_option profile) +{ +struct amd_cpudata *cpudata =dev_get_drvdata (dev); + struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu); +int ret; + +switch (profile) { +case PLATFORM_PROFILE_LOW_POWER : +if (cpudata->policy !=CPUFREQ_POLICY_POWERSAVE ) + cpudata->policy =CPUFREQ_POLICY_POWERSAVE ;So prior to the patch,
cpudata->policyis supposed to mirrorpolicy->policy. With this patch, this assumption is no longer true. So it is possible for the user to again override the choice of EPP set via platform profile by changing the cpufreq governor ?
Quoted 8 lines
Is this the expected behaviour?
The bigger concern is, if the governor was previously "performance" and then the platform profile requested "low power", "cat
/sys/devices/system/cpu/cpuX/cpufreq/scaling_governor" would still show "performance", which is inconsistent with the behaviour.
This ties back to the previous patches for dynamic EPP. My expectation was that when dynamic EPP is enabled that users can't manually set the EPP anymore (it will return -EBUSY) and likewise turning on dynamic EPP should keep the governor as powersave.
I'll double check all those are properly enforced; but that's at least the intent.
IMO this "should" all work because turning on Dynamic EPP sysfs file forces the driver to go through a state transition that it will tear everything down and back up. The policy will come back up in "powersave" even if it was previously in "performance" when the dynamic EPP sysfs file was turned on.
Longer term; I also envision the scheduler influencing EPP values when dynamic_epp is turned on. The "platform profile" would be an "input" to that decision making process (maybe giving a weighting?), not the only lever.
I haven't given any serious look at how to do this with the scheduler, I wanted to lay the foundation first being dynamic EPP and raw EPP.
So even if dynamic_epp isn't interesting "right now" for server because the focus is around behavior for AC/DC, don't write it off just yet.
Mario Limonciello
maintainerRe: [PATCH v2 3/5] cpufreq/amd-pstate: Add support for platform profile class
Quoted 142 lines · Mario Limonciello
Quoted 132 lines · Gautham R. Shenoy
Quoted 115 lines · Mario Limonciello
From: Mario Limonciello <[email protected]>
The platform profile core allows multiple drivers and devices to register platform profile support.
When the legacy platform profile interface is used all drivers will adjust the platform profile as well.
Add support for registering every CPU with the platform profile handler when dynamic EPP is enabled.
The end result will be that changing the platform profile will modify EPP accordingly.
Signed-off-by Mario Limonciello <[email protected]>---
Documentation/admin-guide/pm/amd-pstate.rst| 4 +- drivers/cpufreq/Kconfig.x86 | 1 + drivers/cpufreq/amd-pstate.c | 142 +++++++++++++++++--- drivers/cpufreq/amd-pstate.h | 10 ++4 files changed, 140 insertions(+), 17 deletions(-)Documentation/admin-guide/pm/amd-pstate.rst +0
-0@@ -321,7 +321,9 @@ Whether this behavior is enabled by default withthe kernel config option
at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/ policyX/dynamic_epp``. When set to enabled, the driver will select a different energy performanceDocumentation/admin-guide/pm/amd-pstate.rst +1
-1-profile when the machine is running on battery or AC power. +profile when the machine is running on battery or AC power. Thedriver will
+also register with the platform profile handler to receive notifications of
+user desired power state and react to those.
When set to disabled, the driver will not change the energy performance profile based on the power source and will not react to user desired power state.drivers/cpufreq/Kconfig.x86 +0
-0@@ -40,6 +40,7 @@ config X86_AMD_PSTATEselect
ACPI_PROCESSOR
selectACPI_CPPC_LIBifX86_64
selectCPU_FREQ_GOV_SCHEDUTILif SMP
+ selectACPI_PLATFORM_PROFILE
help
This driver adds a CPUFreq driver which utilizes a fine grain processor performance frequency control range instead of legacydrivers/cpufreq/amd-pstate.c +3
-0@@ -105,6 +105,7 @@ static struct quirk_entry *quirks;* 2 balance_performance * 3 balance_power * 4 power +* 5 custom (for raw EPP values) */ enum energy_perf_value_index { EPP_INDEX_DEFAULT = 0,@@ -112,6 +113,7 @@ enum energy_perf_value_index { EPP_INDEX_BALANCE_PERFORMANCE, EPP_INDEX_BALANCE_POWERSAVE, EPP_INDEX_POWERSAVE, + EPP_INDEX_CUSTOM, }; static const char * const energy_perf_strings[] = {@@ -120,6 +122,7 @@ static const char * const energy_perf_strings[] = { [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance", [EPP_INDEX_BALANCE_POWERSAVE] = "balance_power", [EPP_INDEX_POWERSAVE] = "power", + [EPP_INDEX_CUSTOM] = "custom",NULL
};drivers/cpufreq/amd-pstate.c +1
-0@@ -1073,6 +1076,10 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb, if (event != PSY_EVENT_PROP_CHANGED) return NOTIFY_OK; + /* dynamic actions are only applied while platform profile is inbalanced */
+ if (cpudata->current_profile!=PLATFORM_PROFILE_BALANCED) + return 0;
+
epp =amd_pstate_get_balanced_epp(policy);
ret =amd_pstate_set_epp(policy, epp);drivers/cpufreq/amd-pstate.c +22
-1@@ -1081,14 +1088,84 @@ static int amd_pstate_power_supply_notifier(struct notifier_block *nb, return NOTIFY_OK; } -static void amd_pstate_clear_dynamic_epp(struct cpufreq_policy *policy) + +static int amd_pstate_profile_probe (void *drvdata,unsigned long *choices) +{ + set_bit(PLATFORM_PROFILE_LOW_POWER, choices); + set_bit(PLATFORM_PROFILE_BALANCED, choices); + set_bit(PLATFORM_PROFILE_PERFORMANCE, choices); + + return 0; +} + +static int amd_pstate_profile_get (struct device *dev, + enum platform_profile_option *profile) +{ + struct amd_cpudata *cpudata = dev_get_drvdata(dev); + + *profile = cpudata->current_profile; + + return 0; +} + +static int amd_pstate_profile_set (struct device *dev, + enum platform_profile_option profile)drivers/cpufreq/amd-pstate.c static int · line 1123
Quoted 10 lines
drivers/cpufreq/amd-pstate.c +9
-0+{ + struct amd_cpudata *cpudata = dev_get_drvdata(dev); + struct cpufreq_policy *policy __free(put_cpufreq_policy) =cpufreq_cpu_get (cpudata->cpu); + int ret; + + switch (profile) { + case PLATFORM_PROFILE_LOW_POWER: + if (cpudata->policy != CPUFREQ_POLICY_POWERSAVE) + cpudata->policy = CPUFREQ_POLICY_POWERSAVE;So prior to the patch,
cpudata->policyis supposed to mirror policy->policy. With this patch, this assumption is no longer true. So it is possible for the user to again override the choice of EPP set via platform profile by changing the cpufreq governor ?Quoted 8 lines
Is this the expected behaviour?
The bigger concern is, if the governor was previously "performance" and then the platform profile requested "low power", "cat
/sys/devices/system/cpu/cpuX/cpufreq/scaling_governor" would still show "performance", which is inconsistent with the behaviour.
Quoted 4 lines
This ties back to the previous patches for dynamic EPP. My expectation was that when dynamic EPP is enabled that users can't manually set the EPP anymore (it will return
-EBUSY) and likewise turning on dynamic EPP should keep the governor as powersave.I'll double check all those are properly enforced; but that's at least the intent.
FWIW - I double checked and confirmed that this is working as intended.
* I couldn't change from powersave to performance when dynamic_epp was enabled (-EBUSY)
* I couldn't change energy_performance_preference when dynamic_epp was enabled (-EBUSY)
Quoted 8 lines
IMO this "should" all work because turning on Dynamic EPP sysfs file forces the driver to go through a state transition that it will tear everything down and back up. The policy will come back up in "powersave" even if it was previously in "performance" when the dynamic EPP sysfs file was turned on.
Longer term; I also envision the scheduler influencing EPP values when
dynamic_eppis turned on. The "platform profile" would be an "input" to that decision making process (maybe giving a weighting?), not the only lever.I haven't given any serious look at how to do this with the scheduler, I wanted to lay the foundation first being dynamic EPP and raw EPP.
So even if
dynamic_eppisn't interesting "right now" for server because the focus is around behavior for AC/DC, don't write it off just yet.
Re: [PATCH v2 3/5] cpufreq/amd-pstate: Add support for platform profile class
[...snip...]
Quoted 34 lines · Mario Limonciello
Quoted 33 lines · Mario Limonciello
Quoted 18 lines · Gautham R. Shenoy
Quoted 5 lines
drivers/cpufreq/amd-pstate.c +5
-0+static int amd_pstate_profile_set (struct device *dev, + enum platform_profile_option profile) +{ + struct amd_cpudata *cpudata = dev_get_drvdata(dev); + struct cpufreq_policy *policy __free(put_cpufreq_policy) =Quoted 7 lines
cpufreq_cpu_get(cpudata->cpu);
+ int ret;
+
+ switch (profile) {
+ casePLATFORM_PROFILE_LOW_POWER:
+ if (cpudata->policy!=CPUFREQ_POLICY_POWERSAVE) +cpudata->policy=CPUFREQ_POLICY_POWERSAVE;So prior to the patch,
cpudata->policyis supposed to mirror policy->policy. With this patch, this assumption is no longer true. So it is possible for the user to again override the choice of EPP set via platform profile by changing the cpufreq governor ?Quoted 8 lines
Is this the expected behaviour?
The bigger concern is, if the governor was previously "performance" and then the platform profile requested "low power", "cat
/sys/devices/system/cpu/cpuX/cpufreq/scaling_governor" would still show "performance", which is inconsistent with the behaviour.This ties back to the previous patches for dynamic EPP. My expectation was that when dynamic EPP is enabled that users can't manually set the EPP anymore (it will return
-EBUSY) and likewise turning on dynamic EPP should keep the governor as powersave.
Quoted 8 lines
Quoted 2 lines
I'll double check all those are properly enforced; but that's at least the intent.
FWIW - I double checked and confirmed that this is working as intended.
* I couldn't change from powersave to performance whendynamic_eppwas enabled (-EBUSY)
* I couldn't changeenergy_performance_preferencewhendynamic_eppwas enabled (-EBUSY)
Thanks for double checking this.
Quoted 8 lines
Quoted 8 lines
IMO this "should" all work because turning on Dynamic EPP sysfs file forces the driver to go through a state transition that it will tear everything down and back up. The policy will come back up in "powersave" even if it was previously in "performance" when the dynamic EPP sysfs file was turned on.
Quoted 4 lines
Quoted 4 lines
Longer term; I also envision the scheduler influencing EPP values when
dynamic_eppis turned on. The "platform profile" would be an "input" to that decision making process (maybe giving a weighting?), not the only lever.
Yes, the scheduler influencing the EPP values is something that I have been wanting to explore as well. My idea was to use the nature of the task + the load on the rq to determine the EPP value.
Quoted 7 lines
Quoted 6 lines
I haven't given any serious look at how to do this with the scheduler, I wanted to lay the foundation first being dynamic EPP and raw EPP.
So even if
dynamic_eppisn't interesting "right now" for server because the focus is around behavior for AC/DC, don't write it off just yet.
Fair enough.
Signature · 2 lines
Thanks and Regards gautham.
Mario Limonciello
maintainerRe: [PATCH v2 3/5] cpufreq/amd-pstate: Add support for platform profile class
Quoted 40 lines · Gautham R. Shenoy
[...snip...]
Quoted 37 lines · Mario Limonciello
Quoted 35 lines · Mario Limonciello
Quoted 18 lines · Gautham R. Shenoy
Quoted 5 lines
drivers/cpufreq/amd-pstate.c +5
-0+static int amd_pstate_profile_set (struct device *dev, + enum platform_profile_option profile) +{ + struct amd_cpudata *cpudata = dev_get_drvdata(dev); + struct cpufreq_policy *policy __free(put_cpufreq_policy) =Quoted 7 lines
cpufreq_cpu_get(cpudata->cpu);
+ int ret;
+
+ switch (profile) {
+ casePLATFORM_PROFILE_LOW_POWER:
+ if (cpudata->policy!=CPUFREQ_POLICY_POWERSAVE) +cpudata->policy=CPUFREQ_POLICY_POWERSAVE;So prior to the patch,
cpudata->policyis supposed to mirror policy->policy. With this patch, this assumption is no longer true. So it is possible for the user to again override the choice of EPP set via platform profile by changing the cpufreq governor ?Quoted 8 lines
Is this the expected behaviour?
The bigger concern is, if the governor was previously "performance" and then the platform profile requested "low power", "cat
/sys/devices/system/cpu/cpuX/cpufreq/scaling_governor" would still show "performance", which is inconsistent with the behaviour.This ties back to the previous patches for dynamic EPP. My expectation was that when dynamic EPP is enabled that users can't manually set the EPP anymore (it will return
-EBUSY) and likewise turning on dynamic EPP should keep the governor as powersave.I'll double check all those are properly enforced; but that's at least the intent.
Quoted 7 lines
Quoted 5 lines
FWIW - I double checked and confirmed that this is working as intended.
* I couldn't change from powersave to performance whendynamic_eppwas enabled (-EBUSY)
* I couldn't changeenergy_performance_preferencewhendynamic_eppwas enabled (-EBUSY)Thanks for double checking this.
The other option is to create a "3rd" cpufreq driver for amd-pstate when dynamic epp is in use.
The upside is this one could then exclude "energy_performance_preference" and "energy_performance_available_preferences" so no need to report -EBUSY for that case since you can't manually change EPP.
The downside is that you couldn't discover what the kernel was doing with EPP without ftrace.
Quoted 30 lines
Quoted 10 lines
Quoted 10 lines
IMO this "should" all work because turning on Dynamic EPP sysfs file forces the driver to go through a state transition that it will tear everything down and back up. The policy will come back up in "powersave" even if it was previously in "performance" when the dynamic EPP sysfs file was turned on.
Quoted 4 lines
Quoted 4 lines
Longer term; I also envision the scheduler influencing EPP values when
dynamic_eppis turned on. The "platform profile" would be an "input" to that decision making process (maybe giving a weighting?), not the only lever.Yes, the scheduler influencing the EPP values is something that I have been wanting to explore as well. My idea was to use the nature of the task + the load on the rq to determine the EPP value.
Quoted 7 lines
Quoted 6 lines
I haven't given any serious look at how to do this with the scheduler, I wanted to lay the foundation first being dynamic EPP and raw EPP.
So even if
dynamic_eppisn't interesting "right now" for server because the focus is around behavior for AC/DC, don't write it off just yet.Fair enough.
PATCH v2 4/5 cpufreq/amd-pstate: Add support for raw EPP writes
In reply to Mario LimoncielloFrom: Mario Limonciello <[email protected]>
The energy performance preference field of the CPPC request MSR supports values from 0 to 255, but the strings only offer 4 values.
The other values are useful for tuning the performance of some workloads.
Add support for writing the raw energy performance preference value to the sysfs file. If the last value written was an integer then an integer will be returned. If the last value written was a string then a string will be returned.
--- Documentation/admin-guide/pm/amd-pstate.rst | 16 +++++++++++----- drivers/cpufreq/amd-pstate.c | 11 +++++++++-- drivers/cpufreq/amd-pstate.h | 1 + 3 files changed, 21 insertions(+), 7 deletions(-)
Documentation/admin-guide/pm/amd-pstate.rst +11 -5
@@ -280,16 +280,22 @@ A list of all the supported EPP preferences that could be used for These profiles represent different hints that are provided to the low-level firmware about the user's desired energy vs efficiency tradeoff. ``default`` represents the epp value is set by platform -firmware. This attribute is read-only. +firmware. ``custom`` designates that integer values 0-255 may be written +as well. This attribute is read-only. ``energy_performance_preference`` The current energy performance preference can be read from this attribute. and user can change current preference according to energy or performance needs -Please get all support profiles list from -``energy_performance_available_preferences`` attribute, all the profiles are -integer values defined between 0 to 255 when EPP feature is enabled by platform -firmware, but if the dynamic EPP feature is enabled, driver will block writes. +Coarse named profiles are available in the attribute +``energy_performance_available_preferences``. +Users can also write individual integer values between 0 to 255. +When EPP feature is enabled by platform firmware but if the dynamic EPP feature is +enabled, driver will ignore the written value. Lower epp values shift the bias +towards improved performance while a higher epp value shifts the bias towards +power-savings. The exact impact can change from one platform to the other. +If a valid integer was last written, then a number will be returned on future reads. +If a valid string was last written then a string will be returned on future reads. This attribute is read-write. ``boost``
drivers/cpufreq/amd-pstate.c +9 -2
@@ -1314,6 +1314,7 @@ ssize_t store_energy_performance_preference(struct cpufreq_policy *policy,struct amd_cpudata *cpudata = policy->driver_data;char str_preference[21 ];ssize_t ret; +bool raw_epp = FALSE;u8 epp;if (cpudata->dynamic_epp) {
@@ -1330,6 +1331,7 @@ ssize_t store_energy_performance_preference(struct cpufreq_policy *policy,* matches an index in the energy_perf_strings array */ ret =kstrtou8 (str_preference,0 , &epp); + raw_epp = !ret;if (ret) { ret =match_string (energy_perf_strings,-1 , str_preference);if (ret <0 || ret ==EPP_INDEX_CUSTOM )
@@ -1349,7 +1351,9 @@ ssize_t store_energy_performance_preference(struct cpufreq_policy *policy,if (ret)return ret; -return ret ? ret : count; + cpudata->raw_epp = raw_epp; + +return count; }EXPORT_SYMBOL_GPL (store_energy_performance_preference);
@@ -1360,6 +1364,9 @@ ssize_t show_energy_performance_preference(struct cpufreq_policy *policy, char * epp =FIELD_GET (AMD_CPPC_EPP_PERF_MASK , cpudata->cppc_req_cached); +if (cpudata->raw_epp) +return sysfs_emit (buf,"%u\n" , epp); +switch (epp) {case AMD_CPPC_EPP_PERFORMANCE : preference =EPP_INDEX_PERFORMANCE ;
@@ -1374,7 +1381,7 @@ ssize_t show_energy_performance_preference(struct cpufreq_policy *policy, char * preference =EPP_INDEX_POWERSAVE ;break ;default : -return sysfs_emit (buf,"%u\n" , epp); +return -EINVAL ; }return sysfs_emit (buf,"%s\n" , energy_perf_strings[preference]);
drivers/cpufreq/amd-pstate.h +1 -0
@@ -108,6 +108,7 @@ struct amd_cpudata {u8 epp_default_ac;u8 epp_default_dc;bool dynamic_epp; +bool raw_epp;struct notifier_block power_nb;/* platform profile */
Signature · 1 line
2.43.0
PATCH v2 5/5 cpufreq/amd-pstate-ut: Add a unit test for raw EPP
In reply to Mario LimoncielloFrom: Mario Limonciello <[email protected]>
Ensure that all supported raw EPP values work properly.
--- drivers/cpufreq/amd-pstate-ut.c | 58 +++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+)
drivers/cpufreq/amd-pstate-ut.c +58 -0
@@ -26,6 +26,7 @@#include <linux/kernel.h> #include <linux/module.h> #include <linux/moduleparam.h> +#include <linux/mm.h> #include <linux/fs.h> #include <linux/cleanup.h>
@@ -33,6 +34,7 @@#include "amd-pstate.h" +DEFINE_FREE(free_page, void *, if (_T) free_page((unsigned long)_T))struct amd_pstate_ut_struct {const char *name;
@@ -46,6 +48,7 @@ static int amd_pstate_ut_acpi_cpc_valid(u32 index);static int amd_pstate_ut_check_enabled (u32 index);static int amd_pstate_ut_check_perf (u32 index);static int amd_pstate_ut_check_freq (u32 index); +static int amd_pstate_ut_epp (u32 index);static int amd_pstate_ut_check_driver (u32 index);static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = {
@@ -53,6 +56,7 @@ static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = { {"amd_pstate_ut_check_enabled", amd_pstate_ut_check_enabled }, {"amd_pstate_ut_check_perf", amd_pstate_ut_check_perf }, {"amd_pstate_ut_check_freq", amd_pstate_ut_check_freq }, + {"amd_pstate_ut_epp", amd_pstate_ut_epp }, {"amd_pstate_ut_check_driver", amd_pstate_ut_check_driver } };
@@ -239,6 +243,60 @@ static int amd_pstate_set_mode(enum amd_pstate_mode mode)return amd_pstate_update_status (mode_str,strlen (mode_str)); } +static int amd_pstate_ut_epp (u32 index) +{ + struct cpufreq_policy *policy __free(put_cpufreq_policy) = NULL; + void *buf __free(free_page) = NULL; +struct amd_cpudata *cpudata; +int ret, cpu =0 ; +u16 epp; + + policy =cpufreq_cpu_get (cpu); +if (!policy) +return -ENODEV ; + + cpudata = policy->driver_data; + +/* disable dynamic EPP before running test */ +if (cpudata->dynamic_epp) { +pr_debug ("Dynamic EPP is enabled, disabling it\n" ); +amd_pstate_clear_dynamic_epp (policy); + } + + buf = (void *)__get_free_page (GFP_KERNEL ); +if (!buf) +return -ENOMEM ; + + ret =amd_pstate_set_mode (AMD_PSTATE_ACTIVE ); +if (ret) +return ret; + +for (epp =0 ; epp <=U8_MAX ; epp++) { +u8 val; + +/* write all EPP values */ +memset (buf,0 ,sizeof (*buf)); +snprintf (buf,PAGE_SIZE ,"%d" , epp); + ret =store_energy_performance_preference (policy, buf,sizeof (*buf)); +if (ret <0 ) +return ret; + +/* check if the EPP value reads back correctly for raw numbers */ +memset (buf,0 ,sizeof (*buf)); + ret =show_energy_performance_preference (policy, buf); +if (ret <0 ) +return ret; +strreplace (buf,'\n' ,'\0' ); + ret =kstrtou8 (buf,0 , &val); +if (!ret && epp != val) { +pr_err ("Raw EPP value mismatch: %d != %d\n" , epp, val); +return -EINVAL ; + } + } + +return 0 ; +} +static int amd_pstate_ut_check_driver (u32 index) {enum amd_pstate_mode mode1, mode2 =AMD_PSTATE_DISABLE ;
Signature · 1 line
2.43.0