Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
tools/power x86_energy_perf_policy: Prefer driver HWP limits
When we are successful in using cpufreq min/max limits,
skip setting the raw MSR limits entirely.
This is necessary to avoid undoing any modification that
the cpufreq driver makes to our sysfs request.
eg. intel_pstate may take our request for a limit
that is valid according to HWP.CAP.MIN/MAX and clip
it to be within the range available in PLATFORM_INFO.
Signed-off-by: Len Brown <len.brown@intel.com>
+9
-4
+9
-4
tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
+9
-4
tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
···
62
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unsigned char update_hwp_epp;
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unsigned char update_hwp_min;
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unsigned char update_hwp_max;
65
+
unsigned char hwp_limits_done_via_sysfs;
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unsigned char update_hwp_desired;
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unsigned char update_hwp_window;
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unsigned char update_hwp_use_pkg;
···
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}
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/*
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* If HWP is enabled and cpufreq sysfs attribtes are present,
955
-
* then update sysfs, so that it will not become
956
-
* stale when we write to MSRs.
954
+
* then update via sysfs. The intel_pstate driver may modify (clip)
955
+
* this request, say, when HWP_CAP is outside of PLATFORM_INFO limits,
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+
* and the driver-chosen value takes precidence.
957
+
*
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* (intel_pstate's max_perf_pct and min_perf_pct will follow cpufreq,
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* so we don't have to touch that.)
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*/
···
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1010
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if (update_hwp_max)
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update_cpufreq_scaling_freq(1, cpu, req_update.hwp_max);
1009
+
1010
+
hwp_limits_done_via_sysfs = 1;
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return 0;
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}
···
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if (debug)
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print_hwp_request(cpu, &req, "old: ");
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-
if (update_hwp_min)
1088
+
if (update_hwp_min && !hwp_limits_done_via_sysfs)
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req.hwp_min = req_update.hwp_min;
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-
if (update_hwp_max)
1091
+
if (update_hwp_max && !hwp_limits_done_via_sysfs)
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req.hwp_max = req_update.hwp_max;
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1094
if (update_hwp_desired)