2021-01-11 07:43:47

by Chen Yu

Subject: [PATCH 1/2][v2] cpufreq: intel_pstate: Add parameter to get guarantee frequency

Add input parameter to receive guarantee pstate from intel_pstate_get_hwp_max()
for later use.

No functional change intended.

Signed-off-by: Chen Yu <[email protected]>
---
drivers/cpufreq/intel_pstate.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index eaf32ef7a030..bd3dd1be73ba 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -830,7 +830,7 @@ static struct freq_attr *hwp_cpufreq_attrs[] = {
};

static void intel_pstate_get_hwp_max(struct cpudata *cpu, int *phy_max,
- int *current_max)
+ int *current_max, int *guar_max)
{
u64 cap;

@@ -842,6 +842,7 @@ static void intel_pstate_get_hwp_max(struct cpudata *cpu, int *phy_max,
*current_max = HWP_HIGHEST_PERF(cap);

*phy_max = HWP_HIGHEST_PERF(cap);
+ *guar_max = HWP_GUARANTEED_PERF(cap);
}

static void intel_pstate_hwp_set(unsigned int cpu)
@@ -1205,7 +1206,7 @@ static ssize_t store_no_turbo(struct kobject *a, struct kobj_attribute *b,

static void update_qos_request(enum freq_qos_req_type type)
{
- int max_state, turbo_max, freq, i, perf_pct;
+ int max_state, turbo_max, guar_state, freq, i, perf_pct;
struct freq_qos_request *req;
struct cpufreq_policy *policy;

@@ -1223,7 +1224,7 @@ static void update_qos_request(enum freq_qos_req_type type)
continue;

if (hwp_active)
- intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
+ intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state, &guar_state);
else
turbo_max = cpu->pstate.turbo_pstate;

@@ -1731,9 +1732,9 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;

if (hwp_active && !hwp_mode_bdw) {
- unsigned int phy_max, current_max;
+ unsigned int phy_max, current_max, guar_state;

- intel_pstate_get_hwp_max(cpu, &phy_max, &current_max);
+ intel_pstate_get_hwp_max(cpu, &phy_max, &current_max, &guar_state);
cpu->pstate.turbo_freq = phy_max * cpu->pstate.scaling;
cpu->pstate.turbo_pstate = phy_max;
} else {
@@ -2209,7 +2210,7 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
unsigned int policy_max)
{
int32_t max_policy_perf, min_policy_perf;
- int max_state, turbo_max;
+ int max_state, turbo_max, guar_state;
int max_freq;

/*
@@ -2218,7 +2219,7 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
* rather than pure ratios.
*/
if (hwp_active) {
- intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
+ intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state, &guar_state);
} else {
max_state = global.no_turbo || global.turbo_disabled ?
cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
@@ -2331,9 +2332,9 @@ static void intel_pstate_verify_cpu_policy(struct cpudata *cpu,

update_turbo_state();
if (hwp_active) {
- int max_state, turbo_max;
+ int max_state, turbo_max, guar_state;

- intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
+ intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state, &guar_state);
max_freq = max_state * cpu->pstate.scaling;
} else {
max_freq = intel_pstate_get_max_freq(cpu);
@@ -2691,7 +2692,7 @@ static void intel_cpufreq_adjust_perf(unsigned int cpunum,

static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
- int max_state, turbo_max, min_freq, max_freq, ret;
+ int max_state, turbo_max, guar_state, min_freq, max_freq, ret;
struct freq_qos_request *req;
struct cpudata *cpu;
struct device *dev;
@@ -2719,7 +2720,7 @@ static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
if (hwp_active) {
u64 value;

- intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
+ intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state, &guar_state);
policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY_HWP;
rdmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, &value);
WRITE_ONCE(cpu->hwp_req_cached, value);
--
2.17.1

2021-01-12 00:43:23

by Rafael J. Wysocki

Subject: Re: [PATCH 1/2][v2] cpufreq: intel_pstate: Add parameter to get guarantee frequency

On Mon, Jan 11, 2021 at 8:40 AM Chen Yu <[email protected]> wrote:
>
> Add input parameter to receive guarantee pstate from intel_pstate_get_hwp_max()
> for later use.

I'm not a fan of this change, because the new argument will only be
needed in one place where intel_pstate_get_hwp_max() and it requires
adding redundant local vars and pointless updates elsewhere.

Besides, in intel_pstate_get_cpu_pstates() you can do something like
this after calling intel_pstate_get_hwp_max():

cpu->pstate.max_pstate = HWP_GUARANTEED_PERF(READ_ONCE(cpu->hwp_cap_cached));
cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;

2021-01-12 11:12:12

by Chen Yu

Subject: Re: [PATCH 1/2][v2] cpufreq: intel_pstate: Add parameter to get guarantee frequency

On Mon, Jan 11, 2021 at 01:44:09PM +0100, Rafael J. Wysocki wrote:
> On Mon, Jan 11, 2021 at 8:40 AM Chen Yu <[email protected]> wrote:
> >
> > Add input parameter to receive guarantee pstate from intel_pstate_get_hwp_max()
> > for later use.
>
> I'm not a fan of this change, because the new argument will only be
> needed in one place where intel_pstate_get_hwp_max() and it requires
> adding redundant local vars and pointless updates elsewhere.
>
> Besides, in intel_pstate_get_cpu_pstates() you can do something like
> this after calling intel_pstate_get_hwp_max():
>
> cpu->pstate.max_pstate = HWP_GUARANTEED_PERF(READ_ONCE(cpu->hwp_cap_cached));
> cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
Okay, will do in next version.

Thanks,
Chenyu