Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967473AbdDSVQs (ORCPT ); Wed, 19 Apr 2017 17:16:48 -0400 Received: from mail-io0-f196.google.com ([209.85.223.196]:35552 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966699AbdDSVQn (ORCPT ); Wed, 19 Apr 2017 17:16:43 -0400 From: Doug Smythies X-Google-Original-From: Doug Smythies To: srinivas.pandruvada@linux.intel.com, rjw@rjwysocki.net Cc: dsmythies@telus.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: [PATCH] cpufreq: intel_pstate: allow trace in passive mode Date: Wed, 19 Apr 2017 14:16:17 -0700 Message-Id: <1492636577-8507-1-git-send-email-dsmythies@telus.net> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3185 Lines: 110 Allow use of the trace_pstate_sample trace function when the intel_pstate driver is in passive mode. Since the core_busy and scaled_busy fields are not used, and it might be desirable to know which path through the driver was used, either intel_cpufreq_target or intel_cpufreq_fast_switch, re-task the core_busy field as a flag indicator. The user can then use the intel_pstate_tracer.py utility to summarize and plot the trace. In Passive mode the driver is only called if there is a need to change the target frequency, so durations (time gaps between calls) can be very very long. The user needs to understand, and not be confused by, this limitation. Signed-off-by: Doug Smythies --- drivers/cpufreq/intel_pstate.c | 50 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 283491f..04e91ed 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2271,7 +2271,10 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy, { struct cpudata *cpu = all_cpu_data[policy->cpu]; struct cpufreq_freqs freqs; - int target_pstate; + struct sample *sample; + int target_pstate, from; + u64 time; + bool sample_taken; update_turbo_state(); @@ -2291,12 +2294,32 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy, break; } target_pstate = intel_pstate_prepare_request(cpu, target_pstate); + + from = cpu->pstate.current_pstate; + time = ktime_get(); + sample_taken = intel_pstate_sample(cpu, time); + if (target_pstate != cpu->pstate.current_pstate) { cpu->pstate.current_pstate = target_pstate; wrmsrl_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, target_pstate)); } freqs.new = target_pstate * cpu->pstate.scaling; + + if (sample_taken) { + intel_pstate_calc_avg_perf(cpu); + sample = &cpu->sample; + trace_pstate_sample(0, + 0, + from, + cpu->pstate.current_pstate, + sample->mperf, + sample->aperf, + sample->tsc, + get_avg_frequency(cpu), + fp_toint(cpu->iowait_boost * 100)); + } + cpufreq_freq_transition_end(policy, &freqs, false); return 0; @@ -2306,13 +2329,36 @@ static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy, unsigned int target_freq) { struct cpudata *cpu = all_cpu_data[policy->cpu]; - int target_pstate; + struct sample *sample; + int target_pstate, from; + u64 time; + bool sample_taken; update_turbo_state(); target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling); target_pstate = intel_pstate_prepare_request(cpu, target_pstate); + + from = cpu->pstate.current_pstate; + time = ktime_get(); + sample_taken = intel_pstate_sample(cpu, time); + intel_pstate_update_pstate(cpu, target_pstate); + + if (sample_taken) { + intel_pstate_calc_avg_perf(cpu); + sample = &cpu->sample; + trace_pstate_sample(100, + 0, + from, + cpu->pstate.current_pstate, + sample->mperf, + sample->aperf, + sample->tsc, + get_avg_frequency(cpu), + fp_toint(cpu->iowait_boost * 100)); + } + return target_pstate * cpu->pstate.scaling; } -- 2.7.4