From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: [PATCH] intel_pstate: Update cpu_frequency tracepoint every time Date: Tue, 19 Jul 2016 15:10:37 +0200 Message-ID: <3678564.0E838ntcHL@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7Bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Linux PM list Cc: Linux Kernel Mailing List , Srinivas Pandruvada List-Id: linux-pm@vger.kernel.org From: Rafael J. Wysocki Currently, intel_pstate only updates the cpu_frequency tracepoint if the new P-state to set is different from the current one, but that causes powertop to report 100% idle on an 100% loaded system sometimes. Prevent that from happening by updating the cpu_frequency tracepoint every time intel_pstate_update_pstate() is called. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) Index: linux-pm/drivers/cpufreq/intel_pstate.c =================================================================== --- linux-pm.orig/drivers/cpufreq/intel_pstate.c +++ linux-pm/drivers/cpufreq/intel_pstate.c @@ -1134,17 +1134,12 @@ static void intel_pstate_get_min_max(str *min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf); } -static inline void intel_pstate_record_pstate(struct cpudata *cpu, int pstate) -{ - trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu); - cpu->pstate.current_pstate = pstate; -} - static void intel_pstate_set_min_pstate(struct cpudata *cpu) { int pstate = cpu->pstate.min_pstate; - intel_pstate_record_pstate(cpu, pstate); + trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu); + cpu->pstate.current_pstate = pstate; /* * Generally, there is no guarantee that this code will always run on * the CPU being updated, so force the register update to run on the @@ -1304,10 +1299,11 @@ static inline void intel_pstate_update_p intel_pstate_get_min_max(cpu, &min_perf, &max_perf); pstate = clamp_t(int, pstate, min_perf, max_perf); + trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu); if (pstate == cpu->pstate.current_pstate) return; - intel_pstate_record_pstate(cpu, pstate); + cpu->pstate.current_pstate = pstate; wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate)); }