2024-04-23 08:41:28

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 0/6] AMD Pstate Driver Core Performance Boost

Hi all,
The patchset series add core performance boost feature for AMD pstate
driver including passisve ,guide and active mode support.

User can change core frequency boost control with a new sysfs entry:

"/sys/devices/system/cpu/amd_pstate/cpb_boost"

The legancy boost interface has been removed due to the function
conflict with new cpb_boost which can support all modes.

1) disabble core boost:
$ sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
$ lscpu -ae
CPU NODE SOCKET CORE L1d:L1i:L2:L3 ONLINE MAXMHZ MINMHZ MHZ
0 0 0 0 0:0:0:0 yes 4201.0000 400.0000 2983.578
1 0 0 1 1:1:1:0 yes 4201.0000 400.0000 2983.578
2 0 0 2 2:2:2:0 yes 4201.0000 400.0000 2583.855
3 0 0 3 3:3:3:0 yes 4201.0000 400.0000 2983.578
4 0 0 4 4:4:4:0 yes 4201.0000 400.0000 2983.578

2) enable core boost:
$ sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
$ lscpu -ae
0 0 0 0 0:0:0:0 yes 5759.0000 400.0000 2983.578
1 0 0 1 1:1:1:0 yes 5759.0000 400.0000 2983.578
2 0 0 2 2:2:2:0 yes 5759.0000 400.0000 2983.578
3 0 0 3 3:3:3:0 yes 5759.0000 400.0000 2983.578
4 0 0 4 4:4:4:0 yes 5759.0000 400.0000 2983.578


The patches have been tested with the AMD 7950X processor and many users
would like to get core boost control enabled for power saving.

If you would like to test this patchset, it needs to apply the patchset
based on below one latest version patchset.
https://lore.kernel.org/lkml/[email protected]/


Perry.

Changes from v6:
* reword patch 2 commit log (Gautham)
* update cover letter description(Gautham)
* rebase to kernel v6.9-rc5

Changes from v4:
* drop the legacy boost remove patch, let us keep the legacy interface
in case some applications break.
* rebase to linux-pm/bleeding-edge branch
* rework the patchset base on [PATCH v8 0/8] AMD Pstate Fixes And
Enhancements which has some intial work done there.

Changes from v4:
* move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h
* pick RB flag from Gautham R. Shenoy
* add Cc Oleksandr Natalenko <[email protected]>
* rebase to latest linux-pm/bleeding-edge branch
* rebase the patch set on top of [PATCH v7 0/6] AMD Pstate Fixes And Enhancements
* update [PATCH v7 2/6] to use MSR_K7_HWCR_CPB_DIS_BIT

Changes from v3:
* rebased to linux-pm/bleeding-edge v6.8
* rename global to amd_pstate_global_params(Oleksandr Natalenko)
* remove comments for boot_supported in amd_pstate.h
* fix the compiler warning for amd-pstate-ut.ko
* use for_each_online_cpu in cpb_boost_store which fix the null pointer
error during testing
* fix the max frequency value to be KHz when cpb boost disabled(Gautham R. Shenoy)

Changes from v2:
* move global struct to amd-pstate.h
* fix the amd-pstate-ut with new cpb control interface

Changes from v1:
* drop suspend/resume fix patch 6/7 because of the fix should be in
another fix series instead of CPB feature
* move the set_boost remove patch to the last(Mario)
* Fix commit info with "Closes:" (Mario)
* simplified global.cpb_supported initialization(Mario)
* Add guide mode support for CPB control
* Fixed some Doc typos and add guide mode info to Doc as well.

v1: https://lore.kernel.org/all/[email protected]/
v2: https://lore.kernel.org/lkml/[email protected]/
v3: https://lore.kernel.org/lkml/[email protected]/
v4: https://lore.kernel.org/lkml/[email protected]/
v5: https://lore.kernel.org/lkml/[email protected]/
v6: https://lore.kernel.org/lkml/[email protected]/

Perry Yuan (6):
cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h
cpufreq: amd-pstate: initialize new core precision boost state
cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control
cpufreq: amd-pstate: fix the MSR highest perf will be reset issue
while cpb boost off
Documentation: cpufreq: amd-pstate: introduce the new cpu boost
control method
cpufreq: amd-pstate-ut: support new cpb boost control interface

Documentation/admin-guide/pm/amd-pstate.rst | 11 ++
arch/x86/include/asm/msr-index.h | 2 +
drivers/cpufreq/acpi-cpufreq.c | 2 -
drivers/cpufreq/amd-pstate-ut.c | 2 +-
drivers/cpufreq/amd-pstate.c | 143 ++++++++++++++++++--
include/linux/amd-pstate.h | 13 ++
6 files changed, 160 insertions(+), 13 deletions(-)

--
2.34.1



2024-04-23 08:41:43

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 1/6] cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h

There are some other drivers also need to use the
MSR_K7_HWCR_CPB_DIS_BIT for CPB control bit, so it makes sense to move
the definition to a common header file to allow other driver to use it.

No intentional functional impact.

Suggested-by: Gautham Ranjal Shenoy <[email protected]>
Signed-off-by: Perry Yuan <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
---
arch/x86/include/asm/msr-index.h | 2 ++
drivers/cpufreq/acpi-cpufreq.c | 2 --
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index e72c2b872957..8738a7b3917d 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -782,6 +782,8 @@
#define MSR_K7_HWCR_IRPERF_EN BIT_ULL(MSR_K7_HWCR_IRPERF_EN_BIT)
#define MSR_K7_FID_VID_CTL 0xc0010041
#define MSR_K7_FID_VID_STATUS 0xc0010042
+#define MSR_K7_HWCR_CPB_DIS_BIT 25
+#define MSR_K7_HWCR_CPB_DIS BIT_ULL(MSR_K7_HWCR_CPB_DIS_BIT)

/* K6 MSRs */
#define MSR_K6_WHCR 0xc0000082
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 37f1cdf46d29..2fc82831bddd 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -50,8 +50,6 @@ enum {
#define AMD_MSR_RANGE (0x7)
#define HYGON_MSR_RANGE (0x7)

-#define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
-
struct acpi_cpufreq_data {
unsigned int resume;
unsigned int cpu_feature;
--
2.34.1


2024-04-23 08:42:52

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 4/6] cpufreq: amd-pstate: fix the MSR highest perf will be reset issue while cpb boost off

From: Perry Yuan <[email protected]>

Select the min perf to fix the highest perf value while update pstate
CPPC request MSR register, here we need to limit the max perf value when
CPU boost is disabled in case of that highest perf value in the MSR will be
reset to original highest perf value which cause the BOOST control
failed.

Signed-off-by: Perry Yuan <[email protected]>
---
drivers/cpufreq/amd-pstate.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 49eeb38fcf20..22e5b84dbe28 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -476,6 +476,7 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
u32 des_perf, u32 max_perf, bool fast_switch, int gov_flags)
{
u64 prev = READ_ONCE(cpudata->cppc_req_cached);
+ u32 nominal_perf = READ_ONCE(cpudata->nominal_perf);
u64 value = prev;

min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf,
@@ -495,6 +496,10 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
value &= ~AMD_CPPC_DES_PERF(~0L);
value |= AMD_CPPC_DES_PERF(des_perf);

+ /* limit the max perf when core performance boost feature is disabled */
+ if (!amd_pstate_global_params.cpb_boost)
+ max_perf = min_t(unsigned long, nominal_perf, max_perf);
+
value &= ~AMD_CPPC_MAX_PERF(~0L);
value |= AMD_CPPC_MAX_PERF(max_perf);

--
2.34.1


2024-04-23 08:42:56

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 2/6] cpufreq: amd-pstate: initialize new core precision boost state

From: Perry Yuan <[email protected]>

Add one global `global_params` to represent CPU Performance Boost(cpb)
state for cpu frequency scaling, both active and passive modes all can
support CPU cores frequency boosting control which is based on the BIOS
setting, while BIOS turn on the "Core Performance Boost", it will
allow OS control each core highest perf limitation from OS side.

The active, guided and passive modes of the amd-pstate driver can
support frequency boost control when the "Core Performance Boost"
(CPB) feature is enabled in the BIOS. When enabled in BIOS, the user
has an option at runtime to allow/disallow the cores from operating in
the boost frequency range.

Add an amd_pstate_global_params object to record whether CPB is
enabled in BIOS, and if it has been activated by the user

Reported-by: Artem S. Tashkinov" <[email protected]>
Cc: Oleksandr Natalenko <[email protected]>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217931
Signed-off-by: Perry Yuan <[email protected]>
---
drivers/cpufreq/amd-pstate.c | 39 +++++++++++++++++++++++++++---------
include/linux/amd-pstate.h | 13 ++++++++++++
2 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 83a29b257794..3d86cd7c9073 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -68,6 +68,8 @@ static int cppc_state = AMD_PSTATE_UNDEFINED;
static bool cppc_enabled;
static bool amd_pstate_prefcore = true;
static struct quirk_entry *quirks;
+struct amd_pstate_global_params amd_pstate_global_params;
+EXPORT_SYMBOL_GPL(amd_pstate_global_params);

/*
* AMD Energy Preference Performance (EPP)
@@ -665,18 +667,27 @@ static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state)
return 0;
}

-static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
+static int amd_pstate_boost_init(struct amd_cpudata *cpudata)
{
- u32 highest_perf, nominal_perf;
+ u64 boost_val;
+ int ret;

- highest_perf = READ_ONCE(cpudata->highest_perf);
- nominal_perf = READ_ONCE(cpudata->nominal_perf);
+ ret = rdmsrl_on_cpu(cpudata->cpu, MSR_K7_HWCR, &boost_val);
+ if (ret) {
+ pr_err_once("failed to read initial CPU boost state!\n");
+ return ret;
+ }

- if (highest_perf <= nominal_perf)
- return;
+ amd_pstate_global_params.cpb_supported = !(boost_val & MSR_K7_HWCR_CPB_DIS);
+
+ if (amd_pstate_global_params.cpb_supported) {
+ cpudata->boost_supported = true;
+ current_pstate_driver->boost_enabled = true;
+ }

- cpudata->boost_supported = true;
- current_pstate_driver->boost_enabled = true;
+ amd_pstate_global_params.cpb_boost = amd_pstate_global_params.cpb_supported;
+
+ return ret;
}

static void amd_perf_ctl_reset(unsigned int cpu)
@@ -900,6 +911,11 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)

amd_pstate_init_prefcore(cpudata);

+ /* initialize cpu cores boot state */
+ ret = amd_pstate_boost_init(cpudata);
+ if (ret)
+ goto free_cpudata1;
+
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
@@ -956,7 +972,6 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)

policy->driver_data = cpudata;

- amd_pstate_boost_init(cpudata);
if (!current_pstate_driver->adjust_perf)
current_pstate_driver->adjust_perf = amd_pstate_adjust_perf;

@@ -1363,6 +1378,11 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)

amd_pstate_init_prefcore(cpudata);

+ /* initialize cpu cores boot state */
+ ret = amd_pstate_boost_init(cpudata);
+ if (ret)
+ goto free_cpudata1;
+
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
@@ -1417,7 +1437,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
return ret;
WRITE_ONCE(cpudata->cppc_cap1_cached, value);
}
- amd_pstate_boost_init(cpudata);

return 0;

diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
index 6b832153a126..c5e41de65f70 100644
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -134,4 +134,17 @@ struct quirk_entry {
u32 lowest_freq;
};

+/**
+ * struct amd_pstate_global_params - Global parameters, mostly tunable via sysfs.
+ * @cpb_boost: Whether or not to use boost CPU P-states.
+ * @cpb_supported: Whether or not CPU boost P-states are available
+ * based on the MSR_K7_HWCR bit[25] state
+ */
+struct amd_pstate_global_params {
+ bool cpb_boost;
+ bool cpb_supported;
+};
+
+extern struct amd_pstate_global_params amd_pstate_global_params;
+
#endif /* _LINUX_AMD_PSTATE_H */
--
2.34.1


2024-04-23 08:43:05

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control

From: Perry Yuan <[email protected]>

With this new sysfs entry `cpb_boost`created, user can change CPU boost
state dynamically under `active`, `guided` and `passive` modes.
And the highest perf and frequency will also be updated as the boost
state changing.

0): check current boost state
cat /sys/devices/system/cpu/amd_pstate/cpb_boost

1): disable CPU boost
sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"

2): enable CPU boost
sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217931
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217618
Signed-off-by: Perry Yuan <[email protected]>
---
drivers/cpufreq/amd-pstate.c | 99 ++++++++++++++++++++++++++++++++++++
1 file changed, 99 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 3d86cd7c9073..49eeb38fcf20 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -1291,6 +1291,103 @@ static ssize_t prefcore_show(struct device *dev,
return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore));
}

+static int amd_cpu_boost_update(struct amd_cpudata *cpudata, u32 on)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpudata->cpu);
+ struct cppc_perf_ctrls perf_ctrls;
+ u32 highest_perf, nominal_perf, nominal_freq, max_freq;
+ int ret;
+
+ if (!policy)
+ return -ENODATA;
+
+ highest_perf = READ_ONCE(cpudata->highest_perf);
+ nominal_perf = READ_ONCE(cpudata->nominal_perf);
+ nominal_freq = READ_ONCE(cpudata->nominal_freq);
+ max_freq = READ_ONCE(cpudata->max_freq);
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ u64 value = READ_ONCE(cpudata->cppc_req_cached);
+
+ value &= ~GENMASK_ULL(7, 0);
+ value |= on ? highest_perf : nominal_perf;
+ WRITE_ONCE(cpudata->cppc_req_cached, value);
+
+ wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
+
+ } else {
+ perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
+ ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
+ if (ret) {
+ pr_debug("failed to set energy perf value (%d)\n", ret);
+ return ret;
+ }
+ }
+
+ if (on)
+ policy->cpuinfo.max_freq = max_freq;
+ else
+ policy->cpuinfo.max_freq = nominal_freq;
+
+ policy->max = policy->cpuinfo.max_freq;
+
+ if (cppc_state == AMD_PSTATE_PASSIVE) {
+ ret = freq_qos_update_request(&cpudata->req[1],
+ policy->cpuinfo.max_freq);
+ }
+
+ cpufreq_cpu_release(policy);
+
+ return ret;
+}
+
+static ssize_t cpb_boost_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%u\n", amd_pstate_global_params.cpb_boost);
+}
+
+static ssize_t cpb_boost_store(struct device *dev, struct device_attribute *b,
+ const char *buf, size_t count)
+{
+ bool new_state;
+ ssize_t ret;
+ int cpu;
+
+ mutex_lock(&amd_pstate_driver_lock);
+ if (!amd_pstate_global_params.cpb_supported) {
+ pr_err("Boost mode is not supported by this processor or SBIOS\n");
+ return -EINVAL;
+ }
+
+ ret = kstrtobool(buf, &new_state);
+ if (ret)
+ return -EINVAL;
+
+ amd_pstate_global_params.cpb_boost = !!new_state;
+
+ for_each_present_cpu(cpu) {
+
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ struct amd_cpudata *cpudata = policy->driver_data;
+
+ if (!cpudata) {
+ pr_err("cpudata is NULL\n");
+ ret = -ENODATA;
+ cpufreq_cpu_put(policy);
+ goto err_exit;
+ }
+
+ amd_cpu_boost_update(cpudata, amd_pstate_global_params.cpb_boost);
+ refresh_frequency_limits(policy);
+ cpufreq_cpu_put(policy);
+ }
+
+err_exit:
+ mutex_unlock(&amd_pstate_driver_lock);
+ return ret < 0 ? ret : count;
+}
+
cpufreq_freq_attr_ro(amd_pstate_max_freq);
cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);

@@ -1301,6 +1398,7 @@ cpufreq_freq_attr_rw(energy_performance_preference);
cpufreq_freq_attr_ro(energy_performance_available_preferences);
static DEVICE_ATTR_RW(status);
static DEVICE_ATTR_RO(prefcore);
+static DEVICE_ATTR_RW(cpb_boost);

static struct freq_attr *amd_pstate_attr[] = {
&amd_pstate_max_freq,
@@ -1325,6 +1423,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
static struct attribute *pstate_global_attributes[] = {
&dev_attr_status.attr,
&dev_attr_prefcore.attr,
+ &dev_attr_cpb_boost.attr,
NULL
};

--
2.34.1


2024-04-23 08:43:26

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 5/6] Documentation: cpufreq: amd-pstate: introduce the new cpu boost control method

From: Perry Yuan <[email protected]>

Introduce AMD CPU frequency boosting control sysfs entry which used for
switching boost on and boost off.

If core performance boost is disabled while a core is in a boosted P-state,
the core automatically transitions to the highest performance non-boosted P-state
The highest perf and frequency will be limited by the setting value.

Signed-off-by: Perry Yuan <[email protected]>
---
Documentation/admin-guide/pm/amd-pstate.rst | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 1e0d101b020a..82fbd01da658 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -440,6 +440,17 @@ control its functionality at the system level. They are located in the
This attribute is read-only to check the state of preferred core set
by the kernel parameter.

+``cpb_boost``
+ Specifies whether core performance boost is requested to be enabled or disabled
+ If core performance boost is disabled while a core is in a boosted P-state, the
+ core automatically transitions to the highest performance non-boosted P-state.
+ AMD Core Performance Boost(CPB) is controlled by this new attribute file which
+ allow user to change all cores frequency boosting state. It supports both
+ ``active``, ``passive`` and ``guided`` mode control with below value write to it.
+
+ "0" Disable Core Performance Boosting
+ "1" Enable Core Performance Boosting
+
``cpupower`` tool support for ``amd-pstate``
===============================================

--
2.34.1


2024-04-23 08:44:15

by Yuan, Perry

[permalink] [raw]
Subject: [PATCH v7 6/6] cpufreq: amd-pstate-ut: support new cpb boost control interface

As the new CPB boost control is enabled, pstate unit test needs to remove
legacy `boost_supported` check and start to use new CPB boost control
interface `amd_pstate_global_params.cpb_boost`.

Signed-off-by: Perry Yuan <[email protected]>
---
drivers/cpufreq/amd-pstate-ut.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c
index f04ae67dda37..b3601b0e6dd3 100644
--- a/drivers/cpufreq/amd-pstate-ut.c
+++ b/drivers/cpufreq/amd-pstate-ut.c
@@ -226,7 +226,7 @@ static void amd_pstate_ut_check_freq(u32 index)
goto skip_test;
}

- if (cpudata->boost_supported) {
+ if (amd_pstate_global_params.cpb_boost) {
if ((policy->max == cpudata->max_freq) ||
(policy->max == cpudata->nominal_freq))
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
--
2.34.1


2024-04-23 10:41:20

by Huang Rui

[permalink] [raw]
Subject: Re: [PATCH v7 1/6] cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h

On Tue, Apr 23, 2024 at 04:40:54PM +0800, Yuan, Perry wrote:
> There are some other drivers also need to use the
> MSR_K7_HWCR_CPB_DIS_BIT for CPB control bit, so it makes sense to move
> the definition to a common header file to allow other driver to use it.
>
> No intentional functional impact.
>
> Suggested-by: Gautham Ranjal Shenoy <[email protected]>
> Signed-off-by: Perry Yuan <[email protected]>
> Acked-by: Rafael J. Wysocki <[email protected]>

Acked-by: Huang Rui <[email protected]>

> ---
> arch/x86/include/asm/msr-index.h | 2 ++
> drivers/cpufreq/acpi-cpufreq.c | 2 --
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
> index e72c2b872957..8738a7b3917d 100644
> --- a/arch/x86/include/asm/msr-index.h
> +++ b/arch/x86/include/asm/msr-index.h
> @@ -782,6 +782,8 @@
> #define MSR_K7_HWCR_IRPERF_EN BIT_ULL(MSR_K7_HWCR_IRPERF_EN_BIT)
> #define MSR_K7_FID_VID_CTL 0xc0010041
> #define MSR_K7_FID_VID_STATUS 0xc0010042
> +#define MSR_K7_HWCR_CPB_DIS_BIT 25
> +#define MSR_K7_HWCR_CPB_DIS BIT_ULL(MSR_K7_HWCR_CPB_DIS_BIT)
>
> /* K6 MSRs */
> #define MSR_K6_WHCR 0xc0000082
> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index 37f1cdf46d29..2fc82831bddd 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -50,8 +50,6 @@ enum {
> #define AMD_MSR_RANGE (0x7)
> #define HYGON_MSR_RANGE (0x7)
>
> -#define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
> -
> struct acpi_cpufreq_data {
> unsigned int resume;
> unsigned int cpu_feature;
> --
> 2.34.1
>

2024-04-23 10:55:03

by Huang Rui

[permalink] [raw]
Subject: Re: [PATCH v7 2/6] cpufreq: amd-pstate: initialize new core precision boost state

On Tue, Apr 23, 2024 at 04:40:55PM +0800, Yuan, Perry wrote:
> From: Perry Yuan <[email protected]>
>
> Add one global `global_params` to represent CPU Performance Boost(cpb)
> state for cpu frequency scaling, both active and passive modes all can
> support CPU cores frequency boosting control which is based on the BIOS
> setting, while BIOS turn on the "Core Performance Boost", it will
> allow OS control each core highest perf limitation from OS side.
>
> The active, guided and passive modes of the amd-pstate driver can
> support frequency boost control when the "Core Performance Boost"
> (CPB) feature is enabled in the BIOS. When enabled in BIOS, the user
> has an option at runtime to allow/disallow the cores from operating in
> the boost frequency range.
>
> Add an amd_pstate_global_params object to record whether CPB is
> enabled in BIOS, and if it has been activated by the user
>
> Reported-by: Artem S. Tashkinov" <[email protected]>
> Cc: Oleksandr Natalenko <[email protected]>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> Signed-off-by: Perry Yuan <[email protected]>
> ---
> drivers/cpufreq/amd-pstate.c | 39 +++++++++++++++++++++++++++---------
> include/linux/amd-pstate.h | 13 ++++++++++++
> 2 files changed, 42 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 83a29b257794..3d86cd7c9073 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -68,6 +68,8 @@ static int cppc_state = AMD_PSTATE_UNDEFINED;
> static bool cppc_enabled;
> static bool amd_pstate_prefcore = true;
> static struct quirk_entry *quirks;
> +struct amd_pstate_global_params amd_pstate_global_params;
> +EXPORT_SYMBOL_GPL(amd_pstate_global_params);
>
> /*
> * AMD Energy Preference Performance (EPP)
> @@ -665,18 +667,27 @@ static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state)
> return 0;
> }
>
> -static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
> +static int amd_pstate_boost_init(struct amd_cpudata *cpudata)
> {
> - u32 highest_perf, nominal_perf;
> + u64 boost_val;
> + int ret;
>
> - highest_perf = READ_ONCE(cpudata->highest_perf);
> - nominal_perf = READ_ONCE(cpudata->nominal_perf);
> + ret = rdmsrl_on_cpu(cpudata->cpu, MSR_K7_HWCR, &boost_val);
> + if (ret) {
> + pr_err_once("failed to read initial CPU boost state!\n");
> + return ret;
> + }
>
> - if (highest_perf <= nominal_perf)
> - return;
> + amd_pstate_global_params.cpb_supported = !(boost_val & MSR_K7_HWCR_CPB_DIS);

We have a X86_FEATURE_CPB bit to indicate whether current processor to
support boost. It would better to add a check here if amd-pstate need
forward support.

Thanks,
Ray

> +
> + if (amd_pstate_global_params.cpb_supported) {
> + cpudata->boost_supported = true;
> + current_pstate_driver->boost_enabled = true;
> + }
>
> - cpudata->boost_supported = true;
> - current_pstate_driver->boost_enabled = true;
> + amd_pstate_global_params.cpb_boost = amd_pstate_global_params.cpb_supported;
> +
> + return ret;
> }
>
> static void amd_perf_ctl_reset(unsigned int cpu)
> @@ -900,6 +911,11 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
>
> amd_pstate_init_prefcore(cpudata);
>
> + /* initialize cpu cores boot state */
> + ret = amd_pstate_boost_init(cpudata);
> + if (ret)
> + goto free_cpudata1;
> +
> ret = amd_pstate_init_perf(cpudata);
> if (ret)
> goto free_cpudata1;
> @@ -956,7 +972,6 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
>
> policy->driver_data = cpudata;
>
> - amd_pstate_boost_init(cpudata);
> if (!current_pstate_driver->adjust_perf)
> current_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
>
> @@ -1363,6 +1378,11 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
>
> amd_pstate_init_prefcore(cpudata);
>
> + /* initialize cpu cores boot state */
> + ret = amd_pstate_boost_init(cpudata);
> + if (ret)
> + goto free_cpudata1;
> +
> ret = amd_pstate_init_perf(cpudata);
> if (ret)
> goto free_cpudata1;
> @@ -1417,7 +1437,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
> return ret;
> WRITE_ONCE(cpudata->cppc_cap1_cached, value);
> }
> - amd_pstate_boost_init(cpudata);
>
> return 0;
>
> diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> index 6b832153a126..c5e41de65f70 100644
> --- a/include/linux/amd-pstate.h
> +++ b/include/linux/amd-pstate.h
> @@ -134,4 +134,17 @@ struct quirk_entry {
> u32 lowest_freq;
> };
>
> +/**
> + * struct amd_pstate_global_params - Global parameters, mostly tunable via sysfs.
> + * @cpb_boost: Whether or not to use boost CPU P-states.
> + * @cpb_supported: Whether or not CPU boost P-states are available
> + * based on the MSR_K7_HWCR bit[25] state
> + */
> +struct amd_pstate_global_params {
> + bool cpb_boost;
> + bool cpb_supported;
> +};
> +
> +extern struct amd_pstate_global_params amd_pstate_global_params;
> +
> #endif /* _LINUX_AMD_PSTATE_H */
> --
> 2.34.1
>

2024-04-23 11:00:46

by Huang Rui

[permalink] [raw]
Subject: Re: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control

On Tue, Apr 23, 2024 at 04:40:56PM +0800, Yuan, Perry wrote:
> From: Perry Yuan <[email protected]>
>
> With this new sysfs entry `cpb_boost`created, user can change CPU boost
> state dynamically under `active`, `guided` and `passive` modes.
> And the highest perf and frequency will also be updated as the boost
> state changing.
>
> 0): check current boost state
> cat /sys/devices/system/cpu/amd_pstate/cpb_boost
>
> 1): disable CPU boost
> sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
>
> 2): enable CPU boost
> sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217618
> Signed-off-by: Perry Yuan <[email protected]>
> ---
> drivers/cpufreq/amd-pstate.c | 99 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 99 insertions(+)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 3d86cd7c9073..49eeb38fcf20 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1291,6 +1291,103 @@ static ssize_t prefcore_show(struct device *dev,
> return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore));
> }
>
> +static int amd_cpu_boost_update(struct amd_cpudata *cpudata, u32 on)
> +{
> + struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpudata->cpu);
> + struct cppc_perf_ctrls perf_ctrls;
> + u32 highest_perf, nominal_perf, nominal_freq, max_freq;
> + int ret;
> +
> + if (!policy)
> + return -ENODATA;
> +
> + highest_perf = READ_ONCE(cpudata->highest_perf);
> + nominal_perf = READ_ONCE(cpudata->nominal_perf);
> + nominal_freq = READ_ONCE(cpudata->nominal_freq);
> + max_freq = READ_ONCE(cpudata->max_freq);
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + value &= ~GENMASK_ULL(7, 0);
> + value |= on ? highest_perf : nominal_perf;
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> +
> + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> +
> + } else {
> + perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
> + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> + if (ret) {
> + pr_debug("failed to set energy perf value (%d)\n", ret);

Do we need cpufreq_cpu_release here?

> + return ret;
> + }
> + }
> +
> + if (on)
> + policy->cpuinfo.max_freq = max_freq;
> + else
> + policy->cpuinfo.max_freq = nominal_freq;
> +
> + policy->max = policy->cpuinfo.max_freq;
> +
> + if (cppc_state == AMD_PSTATE_PASSIVE) {
> + ret = freq_qos_update_request(&cpudata->req[1],
> + policy->cpuinfo.max_freq);
> + }
> +
> + cpufreq_cpu_release(policy);
> +
> + return ret;
> +}
> +
> +static ssize_t cpb_boost_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%u\n", amd_pstate_global_params.cpb_boost);
> +}
> +
> +static ssize_t cpb_boost_store(struct device *dev, struct device_attribute *b,
> + const char *buf, size_t count)
> +{
> + bool new_state;
> + ssize_t ret;
> + int cpu;
> +
> + mutex_lock(&amd_pstate_driver_lock);
> + if (!amd_pstate_global_params.cpb_supported) {
> + pr_err("Boost mode is not supported by this processor or SBIOS\n");
> + return -EINVAL;
> + }
> +
> + ret = kstrtobool(buf, &new_state);
> + if (ret)

If get a falure, amd_pstate_driver_lock will be always locked.

Thanks,
Ray

> + return -EINVAL;
> +
> + amd_pstate_global_params.cpb_boost = !!new_state;
> +
> + for_each_present_cpu(cpu) {
> +
> + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> + struct amd_cpudata *cpudata = policy->driver_data;
> +
> + if (!cpudata) {
> + pr_err("cpudata is NULL\n");
> + ret = -ENODATA;
> + cpufreq_cpu_put(policy);
> + goto err_exit;
> + }
> +
> + amd_cpu_boost_update(cpudata, amd_pstate_global_params.cpb_boost);
> + refresh_frequency_limits(policy);
> + cpufreq_cpu_put(policy);
> + }
> +
> +err_exit:
> + mutex_unlock(&amd_pstate_driver_lock);
> + return ret < 0 ? ret : count;
> +}
> +
> cpufreq_freq_attr_ro(amd_pstate_max_freq);
> cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>
> @@ -1301,6 +1398,7 @@ cpufreq_freq_attr_rw(energy_performance_preference);
> cpufreq_freq_attr_ro(energy_performance_available_preferences);
> static DEVICE_ATTR_RW(status);
> static DEVICE_ATTR_RO(prefcore);
> +static DEVICE_ATTR_RW(cpb_boost);
>
> static struct freq_attr *amd_pstate_attr[] = {
> &amd_pstate_max_freq,
> @@ -1325,6 +1423,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
> static struct attribute *pstate_global_attributes[] = {
> &dev_attr_status.attr,
> &dev_attr_prefcore.attr,
> + &dev_attr_cpb_boost.attr,
> NULL
> };
>
> --
> 2.34.1
>

2024-04-23 11:07:50

by Huang Rui

[permalink] [raw]
Subject: Re: [PATCH v7 6/6] cpufreq: amd-pstate-ut: support new cpb boost control interface

On Tue, Apr 23, 2024 at 04:40:59PM +0800, Yuan, Perry wrote:
> As the new CPB boost control is enabled, pstate unit test needs to remove
> legacy `boost_supported` check and start to use new CPB boost control
> interface `amd_pstate_global_params.cpb_boost`.
>
> Signed-off-by: Perry Yuan <[email protected]>

Acked-by: Huang Rui <[email protected]>

> ---
> drivers/cpufreq/amd-pstate-ut.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/amd-pstate-ut.c b/drivers/cpufreq/amd-pstate-ut.c
> index f04ae67dda37..b3601b0e6dd3 100644
> --- a/drivers/cpufreq/amd-pstate-ut.c
> +++ b/drivers/cpufreq/amd-pstate-ut.c
> @@ -226,7 +226,7 @@ static void amd_pstate_ut_check_freq(u32 index)
> goto skip_test;
> }
>
> - if (cpudata->boost_supported) {
> + if (amd_pstate_global_params.cpb_boost) {
> if ((policy->max == cpudata->max_freq) ||
> (policy->max == cpudata->nominal_freq))
> amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
> --
> 2.34.1
>

2024-04-23 11:12:06

by Huang Rui

[permalink] [raw]
Subject: Re: [PATCH v7 4/6] cpufreq: amd-pstate: fix the MSR highest perf will be reset issue while cpb boost off

On Tue, Apr 23, 2024 at 04:40:57PM +0800, Yuan, Perry wrote:
> From: Perry Yuan <[email protected]>
>
> Select the min perf to fix the highest perf value while update pstate
> CPPC request MSR register, here we need to limit the max perf value when
> CPU boost is disabled in case of that highest perf value in the MSR will be
> reset to original highest perf value which cause the BOOST control
> failed.
>
> Signed-off-by: Perry Yuan <[email protected]>

Acked-by: Huang Rui <[email protected]>

> ---
> drivers/cpufreq/amd-pstate.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 49eeb38fcf20..22e5b84dbe28 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -476,6 +476,7 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
> u32 des_perf, u32 max_perf, bool fast_switch, int gov_flags)
> {
> u64 prev = READ_ONCE(cpudata->cppc_req_cached);
> + u32 nominal_perf = READ_ONCE(cpudata->nominal_perf);
> u64 value = prev;
>
> min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf,
> @@ -495,6 +496,10 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
> value &= ~AMD_CPPC_DES_PERF(~0L);
> value |= AMD_CPPC_DES_PERF(des_perf);
>
> + /* limit the max perf when core performance boost feature is disabled */
> + if (!amd_pstate_global_params.cpb_boost)
> + max_perf = min_t(unsigned long, nominal_perf, max_perf);
> +
> value &= ~AMD_CPPC_MAX_PERF(~0L);
> value |= AMD_CPPC_MAX_PERF(max_perf);
>
> --
> 2.34.1
>

2024-04-25 21:24:31

by Mario Limonciello

[permalink] [raw]
Subject: Re: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control

On 4/23/2024 03:40, Perry Yuan wrote:
> From: Perry Yuan <[email protected]>
>
> With this new sysfs entry `cpb_boost`created, user can change CPU boost
> state dynamically under `active`, `guided` and `passive` modes.
> And the highest perf and frequency will also be updated as the boost
> state changing.
>
> 0): check current boost state
> cat /sys/devices/system/cpu/amd_pstate/cpb_boost
>
> 1): disable CPU boost
> sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
>
> 2): enable CPU boost
> sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217618
> Signed-off-by: Perry Yuan <[email protected]>
> ---
> drivers/cpufreq/amd-pstate.c | 99 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 99 insertions(+)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 3d86cd7c9073..49eeb38fcf20 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1291,6 +1291,103 @@ static ssize_t prefcore_show(struct device *dev,
> return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore));
> }
>
> +static int amd_cpu_boost_update(struct amd_cpudata *cpudata, u32 on)
> +{
> + struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpudata->cpu);
> + struct cppc_perf_ctrls perf_ctrls;
> + u32 highest_perf, nominal_perf, nominal_freq, max_freq;
> + int ret;
> +
> + if (!policy)
> + return -ENODATA;
> +
> + highest_perf = READ_ONCE(cpudata->highest_perf);
> + nominal_perf = READ_ONCE(cpudata->nominal_perf);
> + nominal_freq = READ_ONCE(cpudata->nominal_freq);
> + max_freq = READ_ONCE(cpudata->max_freq);
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + value &= ~GENMASK_ULL(7, 0);
> + value |= on ? highest_perf : nominal_perf;
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> +
> + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> +
> + } else {
> + perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
> + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> + if (ret) {
> + pr_debug("failed to set energy perf value (%d)\n", ret);
> + return ret;
> + }
> + }
> +
> + if (on)
> + policy->cpuinfo.max_freq = max_freq;
> + else
> + policy->cpuinfo.max_freq = nominal_freq;
> +
> + policy->max = policy->cpuinfo.max_freq;
> +
> + if (cppc_state == AMD_PSTATE_PASSIVE) {
> + ret = freq_qos_update_request(&cpudata->req[1],
> + policy->cpuinfo.max_freq);
> + }
> +
> + cpufreq_cpu_release(policy);
> +
> + return ret;
> +}
> +
> +static ssize_t cpb_boost_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%u\n", amd_pstate_global_params.cpb_boost);
> +}
> +
> +static ssize_t cpb_boost_store(struct device *dev, struct device_attribute *b,
> + const char *buf, size_t count)
> +{
> + bool new_state;
> + ssize_t ret;
> + int cpu;
> +
> + mutex_lock(&amd_pstate_driver_lock);

This mutex lock should be after the check for cpb_supported and
kstrtobool check. Right now you have two cases that the lock doesn't
get released.

> + if (!amd_pstate_global_params.cpb_supported) {
> + pr_err("Boost mode is not supported by this processor or SBIOS\n");
> + return -EINVAL;
> + }
> +
> + ret = kstrtobool(buf, &new_state);
> + if (ret)
> + return -EINVAL;
> +
> + amd_pstate_global_params.cpb_boost = !!new_state;
> +
> + for_each_present_cpu(cpu) {
> +
> + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> + struct amd_cpudata *cpudata = policy->driver_data;
> +
> + if (!cpudata) {
> + pr_err("cpudata is NULL\n");
> + ret = -ENODATA;
> + cpufreq_cpu_put(policy);
> + goto err_exit;
> + }
> +
> + amd_cpu_boost_update(cpudata, amd_pstate_global_params.cpb_boost);
> + refresh_frequency_limits(policy);
> + cpufreq_cpu_put(policy);
> + }
> +
> +err_exit:
> + mutex_unlock(&amd_pstate_driver_lock);
> + return ret < 0 ? ret : count;
> +}
> +
> cpufreq_freq_attr_ro(amd_pstate_max_freq);
> cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>
> @@ -1301,6 +1398,7 @@ cpufreq_freq_attr_rw(energy_performance_preference);
> cpufreq_freq_attr_ro(energy_performance_available_preferences);
> static DEVICE_ATTR_RW(status);
> static DEVICE_ATTR_RO(prefcore);
> +static DEVICE_ATTR_RW(cpb_boost);
>
> static struct freq_attr *amd_pstate_attr[] = {
> &amd_pstate_max_freq,
> @@ -1325,6 +1423,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
> static struct attribute *pstate_global_attributes[] = {
> &dev_attr_status.attr,
> &dev_attr_prefcore.attr,
> + &dev_attr_cpb_boost.attr,
> NULL
> };
>


2024-04-26 06:40:18

by Yuan, Perry

[permalink] [raw]
Subject: RE: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control

[AMD Official Use Only - General]

Hi Mario


> -----Original Message-----
> From: Limonciello, Mario <[email protected]>
> Sent: Friday, April 26, 2024 5:17 AM
> To: Yuan, Perry <[email protected]>; [email protected];
> [email protected]; Shenoy, Gautham Ranjal
> <[email protected]>; Petkov, Borislav <[email protected]>;
> Huang, Ray <[email protected]>; Deucher, Alexander
> <[email protected]>
> Cc: Huang, Shimmer <[email protected]>; [email protected];
> Du, Xiaojian <[email protected]>; Meng, Li (Jassmine)
> <[email protected]>; [email protected]; [email protected]
> Subject: Re: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs
> entry for boost control
>
> On 4/23/2024 03:40, Perry Yuan wrote:
> > From: Perry Yuan <[email protected]>
> >
> > With this new sysfs entry `cpb_boost`created, user can change CPU
> > boost state dynamically under `active`, `guided` and `passive` modes.
> > And the highest perf and frequency will also be updated as the boost
> > state changing.
> >
> > 0): check current boost state
> > cat /sys/devices/system/cpu/amd_pstate/cpb_boost
> >
> > 1): disable CPU boost
> > sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> >
> > 2): enable CPU boost
> > sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> >
> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217618
> > Signed-off-by: Perry Yuan <[email protected]>
> > ---
> > drivers/cpufreq/amd-pstate.c | 99
> ++++++++++++++++++++++++++++++++++++
> > 1 file changed, 99 insertions(+)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c
> > b/drivers/cpufreq/amd-pstate.c index 3d86cd7c9073..49eeb38fcf20 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -1291,6 +1291,103 @@ static ssize_t prefcore_show(struct device *dev,
> > return sysfs_emit(buf, "%s\n",
> str_enabled_disabled(amd_pstate_prefcore));
> > }
> >
> > +static int amd_cpu_boost_update(struct amd_cpudata *cpudata, u32 on)
> > +{
> > + struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpudata->cpu);
> > + struct cppc_perf_ctrls perf_ctrls;
> > + u32 highest_perf, nominal_perf, nominal_freq, max_freq;
> > + int ret;
> > +
> > + if (!policy)
> > + return -ENODATA;
> > +
> > + highest_perf = READ_ONCE(cpudata->highest_perf);
> > + nominal_perf = READ_ONCE(cpudata->nominal_perf);
> > + nominal_freq = READ_ONCE(cpudata->nominal_freq);
> > + max_freq = READ_ONCE(cpudata->max_freq);
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + value &= ~GENMASK_ULL(7, 0);
> > + value |= on ? highest_perf : nominal_perf;
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > +
> > + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> > +
> > + } else {
> > + perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
> > + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> > + if (ret) {
> > + pr_debug("failed to set energy perf value (%d)\n", ret);
> > + return ret;
> > + }
> > + }
> > +
> > + if (on)
> > + policy->cpuinfo.max_freq = max_freq;
> > + else
> > + policy->cpuinfo.max_freq = nominal_freq;
> > +
> > + policy->max = policy->cpuinfo.max_freq;
> > +
> > + if (cppc_state == AMD_PSTATE_PASSIVE) {
> > + ret = freq_qos_update_request(&cpudata->req[1],
> > + policy->cpuinfo.max_freq);
> > + }
> > +
> > + cpufreq_cpu_release(policy);
> > +
> > + return ret;
> > +}
> > +
> > +static ssize_t cpb_boost_show(struct device *dev,
> > + struct device_attribute *attr, char *buf) {
> > + return sysfs_emit(buf, "%u\n", amd_pstate_global_params.cpb_boost);
> > +}
> > +
> > +static ssize_t cpb_boost_store(struct device *dev, struct device_attribute *b,
> > + const char *buf, size_t count) {
> > + bool new_state;
> > + ssize_t ret;
> > + int cpu;
> > +
> > + mutex_lock(&amd_pstate_driver_lock);
>
> This mutex lock should be after the check for cpb_supported and kstrtobool
> check. Right now you have two cases that the lock doesn't get released.

Yes, the issue has been resolved by v8.
I have made one new version addressing the feedback from you and Ray
https://lore.kernel.org/lkml/[email protected]/
Please help to take a look.

Thank you.

Perry.


>
> > + if (!amd_pstate_global_params.cpb_supported) {
> > + pr_err("Boost mode is not supported by this processor or
> SBIOS\n");
> > + return -EINVAL;
> > + }
> > +
> > + ret = kstrtobool(buf, &new_state);
> > + if (ret)
> > + return -EINVAL;
> > +
> > + amd_pstate_global_params.cpb_boost = !!new_state;
> > +
> > + for_each_present_cpu(cpu) {
> > +
> > + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > +
> > + if (!cpudata) {
> > + pr_err("cpudata is NULL\n");
> > + ret = -ENODATA;
> > + cpufreq_cpu_put(policy);
> > + goto err_exit;
> > + }
> > +
> > + amd_cpu_boost_update(cpudata,
> amd_pstate_global_params.cpb_boost);
> > + refresh_frequency_limits(policy);
> > + cpufreq_cpu_put(policy);
> > + }
> > +
> > +err_exit:
> > + mutex_unlock(&amd_pstate_driver_lock);
> > + return ret < 0 ? ret : count;
> > +}
> > +
> > cpufreq_freq_attr_ro(amd_pstate_max_freq);
> > cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
> >
> > @@ -1301,6 +1398,7 @@
> cpufreq_freq_attr_rw(energy_performance_preference);
> > cpufreq_freq_attr_ro(energy_performance_available_preferences);
> > static DEVICE_ATTR_RW(status);
> > static DEVICE_ATTR_RO(prefcore);
> > +static DEVICE_ATTR_RW(cpb_boost);
> >
> > static struct freq_attr *amd_pstate_attr[] = {
> > &amd_pstate_max_freq,
> > @@ -1325,6 +1423,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
> > static struct attribute *pstate_global_attributes[] = {
> > &dev_attr_status.attr,
> > &dev_attr_prefcore.attr,
> > + &dev_attr_cpb_boost.attr,
> > NULL
> > };
> >

2024-04-26 06:41:05

by Yuan, Perry

[permalink] [raw]
Subject: RE: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs entry for boost control

[AMD Official Use Only - General]

Hi Ray.

> -----Original Message-----
> From: Huang, Ray <[email protected]>
> Sent: Tuesday, April 23, 2024 7:00 PM
> To: Yuan, Perry <[email protected]>
> Cc: [email protected]; Limonciello, Mario
> <[email protected]>; [email protected]; Shenoy, Gautham
> Ranjal <[email protected]>; Petkov, Borislav
> <[email protected]>; Deucher, Alexander
> <[email protected]>; Huang, Shimmer <[email protected]>;
> [email protected]; Du, Xiaojian <[email protected]>; Meng, Li
> (Jassmine) <[email protected]>; [email protected]; linux-
> [email protected]
> Subject: Re: [PATCH v7 3/6] cpufreq: amd-pstate: implement cpb_boost sysfs
> entry for boost control
>
> On Tue, Apr 23, 2024 at 04:40:56PM +0800, Yuan, Perry wrote:
> > From: Perry Yuan <[email protected]>
> >
> > With this new sysfs entry `cpb_boost`created, user can change CPU
> > boost state dynamically under `active`, `guided` and `passive` modes.
> > And the highest perf and frequency will also be updated as the boost
> > state changing.
> >
> > 0): check current boost state
> > cat /sys/devices/system/cpu/amd_pstate/cpb_boost
> >
> > 1): disable CPU boost
> > sudo bash -c "echo 0 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> >
> > 2): enable CPU boost
> > sudo bash -c "echo 1 > /sys/devices/system/cpu/amd_pstate/cpb_boost"
> >
> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217618
> > Signed-off-by: Perry Yuan <[email protected]>
> > ---
> > drivers/cpufreq/amd-pstate.c | 99
> > ++++++++++++++++++++++++++++++++++++
> > 1 file changed, 99 insertions(+)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c
> > b/drivers/cpufreq/amd-pstate.c index 3d86cd7c9073..49eeb38fcf20 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -1291,6 +1291,103 @@ static ssize_t prefcore_show(struct device *dev,
> > return sysfs_emit(buf, "%s\n",
> > str_enabled_disabled(amd_pstate_prefcore));
> > }
> >
> > +static int amd_cpu_boost_update(struct amd_cpudata *cpudata, u32 on)
> > +{
> > + struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpudata->cpu);
> > + struct cppc_perf_ctrls perf_ctrls;
> > + u32 highest_perf, nominal_perf, nominal_freq, max_freq;
> > + int ret;
> > +
> > + if (!policy)
> > + return -ENODATA;
> > +
> > + highest_perf = READ_ONCE(cpudata->highest_perf);
> > + nominal_perf = READ_ONCE(cpudata->nominal_perf);
> > + nominal_freq = READ_ONCE(cpudata->nominal_freq);
> > + max_freq = READ_ONCE(cpudata->max_freq);
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + value &= ~GENMASK_ULL(7, 0);
> > + value |= on ? highest_perf : nominal_perf;
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > +
> > + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> > +
> > + } else {
> > + perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
> > + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> > + if (ret) {
> > + pr_debug("failed to set energy perf value (%d)\n", ret);
>
> Do we need cpufreq_cpu_release here?
>


Yes, the issue has been resolved by v8.
I have made one new version addressing the feedback.
https://lore.kernel.org/lkml/[email protected]/
Please help to take a look.

Thank you.

Perry.

> > + return ret;
> > + }
> > + }
> > +
> > + if (on)
> > + policy->cpuinfo.max_freq = max_freq;
> > + else
> > + policy->cpuinfo.max_freq = nominal_freq;
> > +
> > + policy->max = policy->cpuinfo.max_freq;
> > +
> > + if (cppc_state == AMD_PSTATE_PASSIVE) {
> > + ret = freq_qos_update_request(&cpudata->req[1],
> > + policy->cpuinfo.max_freq);
> > + }
> > +
> > + cpufreq_cpu_release(policy);
> > +
> > + return ret;
> > +}
> > +
> > +static ssize_t cpb_boost_show(struct device *dev,
> > + struct device_attribute *attr, char *buf) {
> > + return sysfs_emit(buf, "%u\n", amd_pstate_global_params.cpb_boost);
> > +}
> > +
> > +static ssize_t cpb_boost_store(struct device *dev, struct device_attribute *b,
> > + const char *buf, size_t count) {
> > + bool new_state;
> > + ssize_t ret;
> > + int cpu;
> > +
> > + mutex_lock(&amd_pstate_driver_lock);
> > + if (!amd_pstate_global_params.cpb_supported) {
> > + pr_err("Boost mode is not supported by this processor or
> SBIOS\n");
> > + return -EINVAL;
> > + }
> > +
> > + ret = kstrtobool(buf, &new_state);
> > + if (ret)
>
> If get a falure, amd_pstate_driver_lock will be always locked.
>
> Thanks,
> Ray
>
> > + return -EINVAL;
> > +
> > + amd_pstate_global_params.cpb_boost = !!new_state;
> > +
> > + for_each_present_cpu(cpu) {
> > +
> > + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > +
> > + if (!cpudata) {
> > + pr_err("cpudata is NULL\n");
> > + ret = -ENODATA;
> > + cpufreq_cpu_put(policy);
> > + goto err_exit;
> > + }
> > +
> > + amd_cpu_boost_update(cpudata,
> amd_pstate_global_params.cpb_boost);
> > + refresh_frequency_limits(policy);
> > + cpufreq_cpu_put(policy);
> > + }
> > +
> > +err_exit:
> > + mutex_unlock(&amd_pstate_driver_lock);
> > + return ret < 0 ? ret : count;
> > +}
> > +
> > cpufreq_freq_attr_ro(amd_pstate_max_freq);
> > cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
> >
> > @@ -1301,6 +1398,7 @@
> > cpufreq_freq_attr_rw(energy_performance_preference);
> > cpufreq_freq_attr_ro(energy_performance_available_preferences);
> > static DEVICE_ATTR_RW(status);
> > static DEVICE_ATTR_RO(prefcore);
> > +static DEVICE_ATTR_RW(cpb_boost);
> >
> > static struct freq_attr *amd_pstate_attr[] = {
> > &amd_pstate_max_freq,
> > @@ -1325,6 +1423,7 @@ static struct freq_attr *amd_pstate_epp_attr[] =
> > { static struct attribute *pstate_global_attributes[] = {
> > &dev_attr_status.attr,
> > &dev_attr_prefcore.attr,
> > + &dev_attr_cpb_boost.attr,
> > NULL
> > };
> >
> > --
> > 2.34.1
> >