https://github.com/torvalds/linux
Revision b00345d1994d588fa2687e1238fcd542f0320cba authored by Srinivas Pandruvada on 15 June 2016, 06:12:59 UTC, committed by Rafael J. Wysocki on 14 June 2016, 23:56:47 UTC
The maximum turbo P-State used by the intel_pstate driver may be limited by ACPI _PSS table entry 0. After commit 9522a2ff9cde (cpufreq: intel_pstate: Enforce _PPC limits), the maximum performance on servers will be capped by the _PSS table entry 0 by default. Even though that is formally correct, it may lead to preformance regressions in some cases. Namely, if the _PSS table entry 0 is not the maximum turbo P-State, performance measured after commit 9522a2ff9cde will not match the performance measured before that commit on the same system. For this reason, modify the code to always use the maximum turbo frequency as the one that corresponds to _PSS table entry 0 if turbo is enabled in the BIOS. This way, the performance levels from before commit 9522a2ff9cde will be restored on the affected systems. Fixes: 9522a2ff9cde (cpufreq: intel_pstate: Enforce _PPC limits) Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw : Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1 parent 5edb564
Tip revision: b00345d1994d588fa2687e1238fcd542f0320cba authored by Srinivas Pandruvada on 15 June 2016, 06:12:59 UTC
cpufreq: intel_pstate: Adjust _PSS[0] freqeuency if needed
cpufreq: intel_pstate: Adjust _PSS[0] freqeuency if needed
Tip revision: b00345d
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| COPYING | -rw-r--r-- | 18.3 KB |
| CREDITS | -rw-r--r-- | 95.5 KB |
| Kbuild | -rw-r--r-- | 2.8 KB |
| Kconfig | -rw-r--r-- | 252 bytes |
| MAINTAINERS | -rw-r--r-- | 352.7 KB |
| Makefile | -rw-r--r-- | 56.0 KB |
| README | -rw-r--r-- | 18.1 KB |
| REPORTING-BUGS | -rw-r--r-- | 7.3 KB |
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