From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas Pandruvada Subject: [RFC/RFT] [PATCH 08/10] cpufreq: intel_pstate: Dyanmically update busy pct Date: Tue, 15 May 2018 21:49:09 -0700 Message-ID: <20180516044911.28797-9-srinivas.pandruvada@linux.intel.com> References: <20180516044911.28797-1-srinivas.pandruvada@linux.intel.com> Return-path: In-Reply-To: <20180516044911.28797-1-srinivas.pandruvada@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: srinivas.pandruvada@linux.intel.com, tglx@linutronix.de, mingo@redhat.com, peterz@infradead.org, bp@suse.de, lenb@kernel.org, rjw@rjwysocki.net, mgorman@techsingularity.net Cc: x86@kernel.org, linux-pm@vger.kernel.org, viresh.kumar@linaro.org, juri.lelli@arm.com, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org Calculate hwp_boost_threshold_busy_pct (task busy percent, which is worth boosting) and hwp_boost_pstate_threshold (Don't boost if CPU already has some performance) based on platform, min, max and turbo frequencies. Signed-off-by: Srinivas Pandruvada --- drivers/cpufreq/intel_pstate.c | 40 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index ec455af..c43edce 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1463,6 +1463,42 @@ static inline int intel_pstate_get_sched_util(struct cpudata *cpu) return util * 100 / max; } + +static inline void intel_pstate_update_busy_threshold(struct cpudata *cpu) +{ + if (!hwp_boost_threshold_busy_pct) { + int min_freq, max_freq; + + min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling; + update_turbo_state(); + max_freq = global.turbo_disabled || global.no_turbo ? + cpu->pstate.max_freq : cpu->pstate.turbo_freq; + + /* + * We are guranteed to get atleast min P-state. If we assume + * P-state is proportional to load (such that 10% load + * increase will result in 10% P-state increase), we will + * get at least min P-state till we have atleast + * (min * 100/max) percent cpu load. So any load less than + * than this this we shouldn't do any boost. Then boosting + * is not free, we will add atleast 20% offset. + */ + hwp_boost_threshold_busy_pct = min_freq * 100 / max_freq; + hwp_boost_threshold_busy_pct += 20; + pr_debug("hwp_boost_threshold_busy_pct = %d\n", + hwp_boost_threshold_busy_pct); + } + + /* P1 percent out of total range of P-states */ + if (cpu->pstate.max_freq != cpu->pstate.turbo_freq) { + hwp_boost_pstate_threshold = + cpu->pstate.max_freq * SCHED_CAPACITY_SCALE / cpu->pstate.turbo_freq; + pr_debug("hwp_boost_pstate_threshold = %d\n", + hwp_boost_pstate_threshold); + } + +} + static inline void intel_pstate_update_util_hwp(struct update_util_data *data, u64 time, unsigned int flags) { @@ -2061,8 +2097,10 @@ static int __intel_pstate_cpu_init(struct cpufreq_policy *policy) policy->fast_switch_possible = true; - if (hwp_active) + if (hwp_active) { csd_init(cpu); + intel_pstate_update_busy_threshold(cpu); + } return 0; } -- 2.9.5