From d5a5ffb569478383313b7a7f302cb662dd02fcfe Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Thu, 6 Feb 2025 15:56:59 -0600 Subject: [PATCH] cpufreq/amd-pstate: Stop caching EPP EPP values are cached in the cpudata structure per CPU. This is needless though because they are also cached in the CPPC request variable. Drop the separate cache for EPP values and always reference the CPPC request variable when needed. Signed-off-by: Mario Limonciello --- drivers/cpufreq/amd-pstate.c | 30 ++++++++++++++++-------------- drivers/cpufreq/amd-pstate.h | 1 - 2 files changed, 16 insertions(+), 15 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index f7ef9fb82fb5..c6a1eb2fb936 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -298,8 +298,6 @@ static int msr_update_perf(struct cpufreq_policy *policy, u8 min_perf, } WRITE_ONCE(cpudata->cppc_req_cached, value); - if (epp != cpudata->epp_cached) - WRITE_ONCE(cpudata->epp_cached, epp); return 0; } @@ -350,7 +348,6 @@ static int msr_set_epp(struct cpufreq_policy *policy, u8 epp) } /* update both so that msr_update_perf() can effectively check */ - WRITE_ONCE(cpudata->epp_cached, epp); WRITE_ONCE(cpudata->cppc_req_cached, value); return ret; @@ -367,11 +364,14 @@ static int shmem_set_epp(struct cpufreq_policy *policy, u8 epp) { struct amd_cpudata *cpudata = policy->driver_data; struct cppc_perf_ctrls perf_ctrls; + u8 epp_cached; u64 value; int ret; lockdep_assert_held(&cpudata->lock); + epp_cached = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached); + if (trace_amd_pstate_epp_perf_enabled()) { union perf_cached perf = cpudata->perf; @@ -382,10 +382,10 @@ static int shmem_set_epp(struct cpufreq_policy *policy, u8 epp) FIELD_GET(AMD_CPPC_MAX_PERF_MASK, cpudata->cppc_req_cached), policy->boost_enabled, - epp != cpudata->epp_cached); + epp != epp_cached); } - if (epp == cpudata->epp_cached) + if (epp == epp_cached) return 0; perf_ctrls.energy_perf = epp; @@ -394,7 +394,6 @@ static int shmem_set_epp(struct cpufreq_policy *policy, u8 epp) pr_debug("failed to set energy perf value (%d)\n", ret); return ret; } - WRITE_ONCE(cpudata->epp_cached, epp); value = READ_ONCE(cpudata->cppc_req_cached); value &= ~AMD_CPPC_EPP_PERF_MASK; @@ -1242,9 +1241,11 @@ static ssize_t show_energy_performance_preference( struct cpufreq_policy *policy, char *buf) { struct amd_cpudata *cpudata = policy->driver_data; - u8 preference; + u8 preference, epp; + + epp = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached); - switch (cpudata->epp_cached) { + switch (epp) { case AMD_CPPC_EPP_PERFORMANCE: preference = EPP_INDEX_PERFORMANCE; break; @@ -1612,7 +1613,7 @@ static int amd_pstate_epp_update_limit(struct cpufreq_policy *policy) if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) epp = 0; else - epp = READ_ONCE(cpudata->epp_cached); + epp = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached); perf = READ_ONCE(cpudata->perf); @@ -1648,23 +1649,24 @@ static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy) struct amd_cpudata *cpudata = policy->driver_data; union perf_cached perf = cpudata->perf; int ret; + u8 epp; + + guard(mutex)(&cpudata->lock); + + epp = FIELD_GET(AMD_CPPC_EPP_PERF_MASK, cpudata->cppc_req_cached); pr_debug("AMD CPU Core %d going online\n", cpudata->cpu); ret = amd_pstate_cppc_enable(policy); if (ret) return ret; - - guard(mutex)(&cpudata->lock); - - ret = amd_pstate_update_perf(policy, 0, 0, perf.highest_perf, cpudata->epp_cached, false); + ret = amd_pstate_update_perf(policy, 0, 0, perf.highest_perf, epp, false); if (ret) return ret; cpudata->suspended = false; return 0; - } static int amd_pstate_epp_cpu_offline(struct cpufreq_policy *policy) diff --git a/drivers/cpufreq/amd-pstate.h b/drivers/cpufreq/amd-pstate.h index 16ce631a6c3d..c95b4081a3ff 100644 --- a/drivers/cpufreq/amd-pstate.h +++ b/drivers/cpufreq/amd-pstate.h @@ -100,7 +100,6 @@ struct amd_cpudata { struct cpufreq_policy *policy; /* EPP feature related attributes*/ - u8 epp_cached; bool suspended; u8 epp_default; }; -- 2.11.4.GIT