https://bugzilla.kernel.org/show_bug.cgi?id=51741 Summary: powernow-k8 calls for acpi-cpufreq but doesn’t warn if it’s not available Product: Power Management Version: 2.5 Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: cpufreq AssignedTo: cpufreq@xxxxxxxxxxxxxxx ReportedBy: linuxuser330250@xxxxxxx Regression: No On my system, I used to have powernow-k8 compiled into the kernel, but not acpi-cpufreq. I run Gentoo Linux. With sys-kernel/gentoo-sources-3.6.8, I got the following relevent dmesg output: powernow-k8: Found 1 AMD Phenom(tm) II X6 1090T Processor (6 cpu cores) (version 2.20.00) powernow-k8: Core Performance Boosting: on. powernow-k8: 0 : pstate 0 (3200 MHz) powernow-k8: 1 : pstate 1 (2400 MHz) powernow-k8: 2 : pstate 2 (1600 MHz) powernow-k8: 3 : pstate 3 (800 MHz) Now, with sys-kernel/gentoo-sources-3.7.0, dmesg showed the following: powernow-k8: this CPU is not supported anymore, using acpi-cpufreq instead. This lead me into thinking that acpi-cpufreq was used when it actually wasn’t, because it was missing in my kernel (since I don’t know all config options by heart: I had to check for that). I found that the fans were a bit noisier than normal, so I looked in /proc/cpuinfo, which showed all 6 cores were at 3.2 GHz. I then recompiled the kernel with acpi-cpufreq compiled in and removed powernow-k8. Now /proc/cpuinfo shows 800 MHz on all or most of the cores when the system is mostly idle. Apparently, acpi-cpufreq doesn’t show any output at all, except: acpi-cpufreq: overriding BIOS provided _PSD data My suggestion would be to make powernow-k8 check for the availability of acpi-cpufreq and print out a warning should it not be available. And I also suggest a short “acpi-cpufreq is used for frequency scaling” so one can see that it was loaded alright. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug.-- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
