averello/linux-stable-mirror
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2026-05-26 11:40:24 +02:00
Code Issues Packages Projects Releases Wiki Activity

cpufreq/amd-pstate: Cache the max frequency in cpudata

Browse Source 
The value of maximum frequency is fixed and never changes. Doing
calculations every time based off of perf is unnecessary.

Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Link: https://lore.kernel.org/r/20260326193620.649441-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
This commit is contained in:
Mario Limonciello (AMD)
2026-03-26 14:36:20 -05:00
parent 88d2ca6a68
commit 8cdc494013
2 changed files with 11 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/cpufreq/amd-pstate.c
+9 -18
View File
@@ -826,15 +826,13 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
static int amd_pstate_cpu_boost_update(struct cpufreq_policy *policy, bool on)
{
struct amd_cpudata *cpudata = policy->driver_data;
union perf_cached perf = READ_ONCE(cpudata->perf);
u32 nominal_freq, max_freq;
u32 nominal_freq;
int ret = 0;
nominal_freq = READ_ONCE(cpudata->nominal_freq);
max_freq = perf_to_freq(perf, cpudata->nominal_freq, perf.highest_perf);
if (on)
policy->cpuinfo.max_freq = max_freq;
policy->cpuinfo.max_freq = cpudata->max_freq;
else if (policy->cpuinfo.max_freq > nominal_freq)
policy->cpuinfo.max_freq = nominal_freq;
@@ -1021,13 +1019,15 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
WRITE_ONCE(cpudata->nominal_freq, nominal_freq);
/* max_freq is calculated according to (nominal_freq * highest_perf)/nominal_perf */
max_freq = perf_to_freq(perf, nominal_freq, perf.highest_perf);
WRITE_ONCE(cpudata->max_freq, max_freq);
lowest_nonlinear_freq = perf_to_freq(perf, nominal_freq, perf.lowest_nonlinear_perf);
WRITE_ONCE(cpudata->lowest_nonlinear_freq, lowest_nonlinear_freq);
/**
* Below values need to be initialized correctly, otherwise driver will fail to load
* max_freq is calculated according to (nominal_freq * highest_perf)/nominal_perf
* lowest_nonlinear_freq is a value between [min_freq, nominal_freq]
* Check _CPC in ACPI table objects if any values are incorrect
*/
@@ -1090,9 +1090,7 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
policy->cpuinfo.min_freq = policy->min = perf_to_freq(perf,
cpudata->nominal_freq,
perf.lowest_perf);
policy->cpuinfo.max_freq = policy->max = perf_to_freq(perf,
cpudata->nominal_freq,
perf.highest_perf);
policy->cpuinfo.max_freq = policy->max = cpudata->max_freq;
policy->driver_data = cpudata;
ret = amd_pstate_cppc_enable(policy);
@@ -1167,14 +1165,9 @@ static void amd_pstate_cpu_exit(struct cpufreq_policy *policy)
static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy,
char *buf)
{
struct amd_cpudata *cpudata;
union perf_cached perf;
struct amd_cpudata *cpudata = policy->driver_data;
cpudata = policy->driver_data;
perf = READ_ONCE(cpudata->perf);
return sysfs_emit(buf, "%u\n",
perf_to_freq(perf, cpudata->nominal_freq, perf.highest_perf));
return sysfs_emit(buf, "%u\n", cpudata->max_freq);
}
static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *policy,
@@ -1702,9 +1695,7 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
policy->cpuinfo.min_freq = policy->min = perf_to_freq(perf,
cpudata->nominal_freq,
perf.lowest_perf);
policy->cpuinfo.max_freq = policy->max = perf_to_freq(perf,
cpudata->nominal_freq,
perf.highest_perf);
policy->cpuinfo.max_freq = policy->max = cpudata->max_freq;
policy->driver_data = cpudata;
ret = amd_pstate_cppc_enable(policy);
drivers/cpufreq/amd-pstate.h
+2
View File
@@ -73,6 +73,7 @@ struct amd_aperf_mperf {
* @min_limit_freq: Cached value of policy->min (in khz)
* @max_limit_freq: Cached value of policy->max (in khz)
* @nominal_freq: the frequency (in khz) that mapped to nominal_perf
* @max_freq: in ideal conditions the maximum frequency (in khz) possible frequency
* @lowest_nonlinear_freq: the frequency (in khz) that mapped to lowest_nonlinear_perf
* @floor_freq: Cached value of the user requested floor_freq
* @cur: Difference of Aperf/Mperf/tsc count between last and current sample
@@ -103,6 +104,7 @@ struct amd_cpudata {
u32 min_limit_freq;
u32 max_limit_freq;
u32 nominal_freq;
u32 max_freq;
u32 lowest_nonlinear_freq;
u32 floor_freq;