The intel_pstate CPU frequency scaling driver has always calculated CPU frequency incorrectly. Recent changes have eliminted most of the issues, however the frequency reported in the trace buffer, if used, is incorrect. It remains desireable that cpu->pstate.scaling still be a nice round number for things such as when setting max and min frequencies. So the proposal is to just fix the reported frequency in the trace data. Fixes what remains of [1]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=96521 # [1] Signed-off-by: Doug Smythies <dsmythies@telus.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-cpufreq-x86: cpufreq: x86: Make scaling_cur_freq behave more as expected * pm-cpufreq-docs: cpufreq: docs: Add missing cpuinfo_cur_freq description * intel_pstate: cpufreq: intel_pstate: Drop ->get from intel_pstate structure
The ->get callback in the intel_pstate structure was mostly there for the scaling_cur_freq sysfs attribute to work, but after commit f8475cef9008 (x86: use common aperfmperf_khz_on_cpu() to calculate KHz using APERF/MPERF) that attribute uses arch_freq_get_on_cpu() provided by the x86 arch code on all processors supported by intel_pstate, so it doesn't need the ->get callback from the driver any more. Moreover, the very presence of the ->get callback in the intel_pstate structure causes the cpuinfo_cur_freq attribute to be present when intel_pstate operates in the active mode, which is bogus, because the role of that attribute is to return the current CPU frequency as seen by the hardware. For intel_pstate, though, this is just an average frequency and not really current, but computed for the previous sampling interval (the actual current frequency may be way different at the point this value is obtained by reading from cpuinfo_cur_freq), and after commit 82b4e03e01bc (intel_pstate: skip scheduler hook when in "performance" mode) the value in cpuinfo_cur_freq may be stale or just 0, depending on the driver's operation mode. In fact, however, on the hardware supported by intel_pstate there is no way to read the current CPU frequency from it, so the cpuinfo_cur_freq attribute should not be present at all when this driver is in use. For this reason, drop intel_pstate_get() and clear the ->get callback pointer pointing to it, so that the cpuinfo_cur_freq is not present for intel_pstate in the active mode any more. Fixes: 82b4e03e01bc (intel_pstate: skip scheduler hook when in "performance" mode) Reported-by: Huaisheng Ye <yehs1@lenovo.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* intel_pstate: cpufreq: intel_pstate: Correct the busy calculation for KNL * pm-domains: PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present
* pm-cpufreq-sched: cpufreq: schedutil: Fix sugov_start() versus sugov_update_shared() race * intel_pstate: cpufreq: intel_pstate: Fix ratio setting for min_perf_pct
The busy percent calculated for the Knights Landing (KNL) platform is 1024 times smaller than the correct busy value. This causes performance to get stuck at the lowest ratio. The scaling algorithm used for KNL is performance-based, but it still looks at the CPU load to set the scaled busy factor to 0 when the load is less than 1 percent. In this case, since the computed load is 1024x smaller than it should be, the scaled busy factor will always be 0, irrespective of CPU business. This needs a fix similar to the turbostat one in commit b2b34dfe4d9a (tools/power turbostat: KNL workaround for %Busy and Avg_MHz). For this reason, add one more callback to processor-specific callbacks to specify an MPERF multiplier represented by a number of bit positions to shift the value of that register to the left to copmensate for its rate difference with respect to the TSC. This shift value is used during CPU busy calculations. Fixes: ffb810563c (intel_pstate: Avoid getting stuck in high P-states when idle) Reported-and-tested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When the minimum performance limit percentage is set to the power-up default, it is possible that minimum performance ratio is off by one. In the set_policy() callback the minimum ratio is calculated by applying global.min_perf_pct to turbo_ratio and rounding up, but the power-up default global.min_perf_pct is already rounded up to the next percent in min_perf_pct_min(). That results in two round up operations, so for the default min_perf_pct one of them is not required. It is better to remove rounding up in min_perf_pct_min() as this matches the displayed min_perf_pct prior to commit c5a2ee7dde89 (cpufreq: intel_pstate: Active mode P-state limits rework) in 4.12. For example on a platform with max turbo ratio of 37 and minimum ratio of 10, the min_perf_pct resulted in 28 with the above commit. Before this commit it was 27 and it will be the same after this change. Fixes: 1a4fe38add8b (cpufreq: intel_pstate: Remove max/min fractions to limit performance) Reported-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-domains: PM / Domains: provide pm_genpd_poweroff_noirq() stub Revert "PM / Domains: Handle safely genpd_syscore_switch() call on non-genpd device" * pm-sleep: PM / sleep: constify attribute_group structures * pm-cpufreq: cpufreq: intel_pstate: constify attribute_group structures cpufreq: cpufreq_stats: constify attribute_group structures
attribute_groups are not supposed to change at runtime. All functions working with attribute_groups provided by <linux/sysfs.h> work with const attribute_group. So mark the non-const structs as const. File size before: text data bss dec hex filename 15197 2552 40 17789 457d drivers/cpufreq/intel_pstate.o File size After adding 'const': text data bss dec hex filename 15261 2488 40 17789 457d drivers/cpufreq/intel_pstate.o Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-cpufreq: cpufreq / CPPC: Initialize policy->min to lowest nonlinear performance cpufreq: sfi: make freq_table static cpufreq: exynos5440: Fix inconsistent indenting cpufreq: imx6q: imx6ull should use the same flow as imx6ul cpufreq: dt: Add support for hi3660 * intel_pstate: cpufreq: Update scaling_cur_freq documentation cpufreq: intel_pstate: Clean up after performance governor changes intel_pstate: skip scheduler hook when in "performance" mode intel_pstate: delete scheduler hook in HWP mode x86: use common aperfmperf_khz_on_cpu() to calculate KHz using APERF/MPERF cpufreq: intel_pstate: Remove max/min fractions to limit performance x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz" * pm-cpuidle: cpuidle: menu: allow state 0 to be disabled intel_idle: Use more common logging style x86/ACPI/cstate: Allow ACPI C1 FFH MWAIT use on AMD systems ARM: cpuidle: Support asymmetric idle definition