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2014-02-13turbostat: Use GCC's CPUID functions to support PICJosh Triplett
commit 2b92865e648ce04a39fda4f903784a5d01ecb0dc upstream. turbostat uses inline assembly to call cpuid. On 32-bit x86, on systems that have certain security features enabled by default that make -fPIC the default, this causes a build error: turbostat.c: In function ‘check_cpuid’: turbostat.c:1906:2: error: PIC register clobbered by ‘ebx’ in ‘asm’ asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx"); ^ GCC provides a header cpuid.h, containing a __get_cpuid function that works with both PIC and non-PIC. (On PIC, it saves and restores ebx around the cpuid instruction.) Use that instead. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13turbostat: Don't put unprocessed uapi headers in the include pathJosh Triplett
commit b731f3119de57144e16c19fd593b8daeb637843e upstream. turbostat's Makefile puts arch/x86/include/uapi/ in the include path, so that it can include <asm/msr.h> from it. It isn't in general safe to include even uapi headers directly from the kernel tree without processing them through scripts/headers_install.sh, but asm/msr.h happens to work. However, that include path can break with some versions of system headers, by overriding some system headers with the unprocessed versions directly from the kernel source. For instance: In file included from /build/x86-generic/usr/include/bits/sigcontext.h:28:0, from /build/x86-generic/usr/include/signal.h:339, from /build/x86-generic/usr/include/sys/wait.h:31, from turbostat.c:27: ../../../../arch/x86/include/uapi/asm/sigcontext.h:4:28: fatal error: linux/compiler.h: No such file or directory This occurs because the system bits/sigcontext.h on that build system includes <asm/sigcontext.h>, and asm/sigcontext.h in the kernel source includes <linux/compiler.h>, which scripts/headers_install.sh would have filtered out. Since turbostat really only wants a single header, just include that one header rather than putting an entire directory of kernel headers on the include path. In the process, switch from msr.h to msr-index.h, since turbostat just wants the MSR numbers. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-13turbostat: Increase output buffer size to accommodate C8-C10Josh Triplett
On platforms with C8-C10 support, the additional C-states cause turbostat to overrun its output buffer of 128 bytes per CPU. Increase this to 256 bytes per CPU. [ As a bugfix, this should go into 3.10; however, since the C8-C10 support didn't go in until after 3.9, this need not go into any stable kernel. ] Signed-off-by: Josh Triplett <josh@joshtriplett.org> Cc: Len Brown <len.brown@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-17tools/power turbostat: display C8, C9, C10 residencyKristen Carlson Accardi
Display residency in the new C-states, C8, C9, C10. C8, C9, C10 are present on some: "Fourth Generation Intel(R) Core(TM) Processors", which are based on Intel(R) microarchitecture code name Haswell. Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2013-03-15tools/power turbostat: additional Haswell CPU-idLen Brown
There is an additional HSW CPU-id, 0x46, which has C-states exactly like CPU-id 0x45. Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-13tools/power turbostat: display SMI count by defaultLen Brown
The SMI counter is popular -- so display it by default rather than requiring an option. What the heck, we've blown the 80 column budget on many systems already... Note that the value displayed is the delta during the measurement interval. The absolute value of the counter can still be seen with the generic 32-bit MSR option, ie. -m 0x34 Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-09tools/power turbostat: decode MSR_IA32_POWER_CTLLen Brown
When verbose is enabled, print the C1E-Enable bit in MSR_IA32_POWER_CTL. also delete some redundant tests on the verbose variable. Signed-off-by: Len Brown <len.brown@intel.com>
2013-02-09tools/power turbostat: support HaswellLen Brown
This patch enables turbostat to run properly on the next-generation Intel(R) Microarchitecture, code named "Haswell" (HSW). HSW supports the BCLK and counters found in SNB. Signed-off-by: Len Brown <len.brown@intel.com>
2012-12-18Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux Pull powertool update from Len Brown: "This updates the tree w/ the latest version of turbostat, which reports temperature and - on SNB and later - Watts." Fix up semantic merge conflict as per Len. * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: tools: Allow tools to be installed in a user specified location tools/power: turbostat: make Makefile a bit more capable tools/power x86_energy_perf_policy: close /proc/stat in for_every_cpu() tools/power turbostat: v3.0: monitor Watts and Temperature tools/power turbostat: fix output buffering issue tools/power turbostat: prevent infinite loop on migration error path x86 power: define RAPL MSRs tools/power/x86/turbostat: share kernel MSR #defines
2012-11-30tools: Allow tools to be installed in a user specified locationJosh Boyer
When building x86_energy_perf_policy or turbostat within the confines of a packaging system such as RPM, we need to be able to have it install to the buildroot and not the root filesystem of the build machine. This adds a DESTDIR variable that when set will act as a prefix for the install location of these tools. Signed-off-by: Josh Boyer <jwboyer@redhat.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-30tools/power: turbostat: make Makefile a bit more capableMark Asselstine
The turbostat Makefile is pretty simple, its output is placed in the same directory as the source, the install rule has no concept of a prefix or sysroot, and you can set CC to use a specific compiler but not use the more familiar CROSS_COMPILE. By making a few minor changes these limitations are removed while leaving the default behavior matching what it used to be. Example build with these changes: make CROSS_COMPILE=i686-wrs-linux-gnu- DESTDIR=/tmp install or from the tools directory make CROSS_COMPILE=i686-wrs-linux-gnu- DESTDIR=/tmp turbostat_install Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-30tools/power x86_energy_perf_policy: close /proc/stat in for_every_cpu()Colin Ian King
Instead of returning out of for_every_cpu() we should break out of the loop= which will then tidy up correctly by closing the file /proc/stat. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-30tools/power turbostat: v3.0: monitor Watts and TemperatureLen Brown
Show power in Watts and temperature in Celsius when hardware support is present. Intel's Sandy Bridge and Ivy Bridge processor generations support RAPL (Run-Time-Average-Power-Limiting). Per the Intel SDM (Intel® 64 and IA-32 Architectures Software Developer Manual) RAPL provides hardware energy counters and power control MSRs (Model Specific Registers). RAPL MSRs are designed primarily as a method to implement power capping. However, they are useful for monitoring system power whether or not power capping is used. In addition, Turbostat now shows temperature from DTS (Digital Thermal Sensor) and PTM (Package Thermal Monitor) hardware, if present. As before, turbostat reads MSRs, and never writes MSRs. New columns are present in turbostat output: The Pkg_W column shows Watts for each package (socket) in the system. On multi-socket systems, the system summary on the 1st row shows the sum for all sockets together. The Cor_W column shows Watts due to processors cores. Note that Core_W is included in Pkg_W. The optional GFX_W column shows Watts due to the graphics "un-core". Note that GFX_W is included in Pkg_W. The optional RAM_W column on server processors shows Watts due to DRAM DIMMS. As DRAM DIMMs are outside the processor package, RAM_W is not included in Pkg_W. The optional PKG_% and RAM_% columns on server processors shows the % of time in the measurement interval that RAPL power limiting is in effect on the package and on DRAM. Note that the RAPL energy counters have some limitations. First, hardware updates the counters about once every milli-second. This is fine for typical turbostat measurement intervals > 1 sec. However, when turbostat is used to measure events that approach 1ms, the counters are less useful. Second, the 32-bit energy counters are subject to wrapping. For example, a counter incrementing 15 micro-Joule units on a 130 Watt TDP server processor could (in theory) roll over in about 9 minutes. Turbostat detects and handles up to 1 counter overflow per measurement interval. But when the measurement interval exceeds the guaranteed counter range, we can't detect if more than 1 overflow occured. So in this case turbostat indicates that the results are in question by replacing the fractional part of the Watts in the output with "**": Pkg_W Cor_W GFX_W 3** 0** 0** Third, the RAPL counters are energy (Joule) counters -- they sum up weighted events in the package to estimate energy consumed. They are not analong power (Watt) meters. In practice, they tend to under-count because they don't cover every possible use of energy in the package. The accuracy of the RAPL counters will vary between product generations, and between SKU's in the same product generation, and with temperature. turbostat's -v (verbose) option now displays more power and thermal configuration information -- as shown on the turbostat.8 manual page. For example, it now displays the Package and DRAM Thermal Design Power (TDP): cpu0: MSR_PKG_POWER_INFO: 0x2f064001980410 (130 W TDP, RAPL 51 - 200 W, 0.045898 sec.) cpu0: MSR_DRAM_POWER_INFO,: 0x28025800780118 (35 W TDP, RAPL 15 - 75 W, 0.039062 sec.) cpu8: MSR_PKG_POWER_INFO: 0x2f064001980410 (130 W TDP, RAPL 51 - 200 W, 0.045898 sec.) cpu8: MSR_DRAM_POWER_INFO,: 0x28025800780118 (35 W TDP, RAPL 15 - 75 W, 0.039062 sec.) Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-30tools/power turbostat: fix output buffering issueLen Brown
In periodic mode, turbostat writes to stdout, but users were un-able to re-direct stdout, eg. turbostat > outputfile would result in an empty outputfile. Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-27tools/power turbostat: prevent infinite loop on migration error pathLen Brown
Turbostat assumed if it can't migrate to a CPU, then the CPU must have gone off-line and turbostat should re-initialize with the new topology. But if turbostat can not migrate because it is restricted by a cpuset, then it will fail to migrate even after re-initialization, resulting in an infinite loop. Spit out a warning when we can't migrate and endure only 2 re-initialize cycles in a row before giving up and exiting. Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-24tools/power/x86/turbostat: share kernel MSR #definesLen Brown
Now that turbostat is built in the kernel tree, it can share MSR #defines with the kernel. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
2012-11-01tools/power turbostat: graceful fail on garbage inputLen Brown
When invald MSR's are specified on the command line, turbostat should simply print an error and exit. Signed-off-by: Len Brown <len.brown@intel.com>
2012-11-01tools/power turbostat: Repair Segmentation fault when using -i optionLen Brown
Fix regression caused by commit 8e180f3cb6b7510a3bdf14e16ce87c9f5d86f102 (tools/power turbostat: add [-d MSR#][-D MSR#] options to print counter deltas) Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-06tools/power/turbostat: add option to count SMIs, re-name some optionsLen Brown
Counting SMIs is popular, so add a dedicated "-s" option to do it, and juggle some of the other option letters. -S is now system summary (was -s) -c is 32 bit counter (was -d) -C is 64-bit counter (was -D) -p is 1st thread in core (was -c) -P is 1st thread in package (was -p) bump the minor version number Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-28tools/power turbostat: add [-d MSR#][-D MSR#] options to print counter deltasLen Brown
# turbostat -d 0x34 is useful for printing the number of SMI's within an interval on Nehalem and newer processors. where # turbostat -m 0x34 will simply print out the total SMI count since reset. Suggested-by: Andi Kleen Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-26tools/power turbostat: add [-m MSR#] optionLen Brown
-m MSR# prints the specified MSR in 32-bit format -M MSR# prints the specified MSR in 64-bit format Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-26tools/power turbostat: make -M output prettyLen Brown
The -M option dumps the specified 64-bit MSR with every sample. Previously it was output at the end of each line. However, with the v2 style of printing, the lines are now staggered, making MSR output hard to read. So move the MSR output column to the left where things are aligned. Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-26tools/power turbostat: print more turbo-limit informationLen Brown
The "turbo-limit" is the maximum opportunistic processor speed, assuming no electrical or thermal constraints. For a given processor, the turbo-limit varies, depending on the number of active cores. Generally, there is more opportunity when fewer cores are active. Under the "-v" verbose option, turbostat would print the turbo-limits for the four cases of 1 to 4 cores active. Expand that capability to cover the cases of turbo opportunities with up to 16 cores active. Note that not all hardware platforms supply this information, and that sometimes a valid limit may be specified for a core which is not actually present. Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-26tools/power turbostat: delete unused lineLen Brown
MSR_TSC is no longer needed because we now use RDTSC directly. Signed-off-by: Len Brown <len.brown@intel.com>
2012-09-26tools/power turbostat: run on IVB XeonLen Brown
This fix is required to run on IVB Xeon, which previously had an incorrect cpuid model number listed. Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-20tools/power: turbostat: fix large c1% issueLen Brown
Under some conditions, c1% was displayed as very large number, much higher than 100%. c1% is not measured, it is derived as "that, which is left over" from other counters. However, the other counters are not collected atomically, and so it is possible for c1% to be calaculagted as a small negative number -- displayed as very large positive. There was a check for mperf vs tsc for this already, but it needed to also include the other counters that are used to calculate c1. Signed-off-by: Len Brown <len.brown@intel.com>
2012-07-20tools/power: turbostat v2 - re-write for efficiencyLen Brown
Measuring large profoundly-idle configurations requires turbostat to be more lightweight. Otherwise, the operation of turbostat itself can interfere with the measurements. This re-write makes turbostat topology aware. Hardware is accessed in "topology order". Redundant hardware accesses are deleted. Redundant output is deleted. Also, output is buffered and local RDTSC use replaces remote MSR access for TSC. From a feature point of view, the output looks different since redundant figures are absent. Also, there are now -c and -p options -- to restrict output to the 1st thread in each core, and the 1st thread in each package, respectively. This is helpful to reduce output on big systems, where more detail than the "-s" system summary is desired. Finally, periodic mode output is now on stdout, not stderr. Turbostat v2 is also slightly more robust in handling run-time CPU online/offline events, as it now checks the actual map of on-line cpus rather than just the total number of on-line cpus. Signed-off-by: Len Brown <len.brown@intel.com>
2012-06-04tools/power turbostat: fix IVB supportLen Brown
Initial IVB support went into turbostat in Linux-3.1: 553575f1ae048aa44682b46b3c51929a0b3ad337 (tools turbostat: recognize and run properly on IVB) However, when running on IVB, turbostat would fail to report the new couters added with SNB, c7, pc2 and pc7. So in scenarios where these counters are non-zero on IVB, turbostat would report erroneous residencey results. In particular c7 time would be added to c1 time, since c1 time is calculated as "that which is left over". Also, turbostat reports MHz capabilities when passed the "-v" option, and it would incorrectly report 133MHz bclk instead of 100MHz bclk for IVB, which would inflate GHz reported with that option. This patch is a backport of a fix already included in turbostat v2. Signed-off-by: Len Brown <len.brown@intel.com>
2012-06-04tools/power turbostat: fix un-intended affinity of forked programLen Brown
Linux 3.4 included a modification to turbostat to lower cross-call overhead by using scheduler affinity: 15aaa34654831e98dd76f7738b6c7f5d05a66430 (tools turbostat: reduce measurement overhead due to IPIs) In the use-case where turbostat forks a child program, that change had the un-intended side-effect of binding the child to the last cpu in the system. This change removed the binding before forking the child. This is a back-port of a fix already included in turbostat v2. Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-30tools turbostat: harden against cpu online/offlineLen Brown
Sometimes users have turbostat running in interval mode when they take processors offline/online. Previously, turbostat would survive, but not gracefully. Tighten up the error checking so turbostat notices changesn sooner, and print just 1 line on change: turbostat: re-initialized with num_cpus %d Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-30tools turbostat: reduce measurement overhead due to IPIsLen Brown
turbostat uses /dev/cpu/*/msr interface to read MSRs. For modern systems, it reads 10 MSR/CPU. This can be observed as 10 "Function Call Interrupts" per CPU per sample added to /proc/interrupts. This overhead is measurable on large idle systems, and as Yoquan Song pointed out, it can even trick cpuidle into thinking the system is busy. Here turbostat re-schedules itself in-turn to each CPU so that its MSR reads will always be local. This replaces the 10 "Function Call Interrupts" with a single "Rescheduling interrupt" per sample per CPU. On an idle 32-CPU system, this shifts some residency from the shallow c1 state to the deeper c7 state: # ./turbostat.old -s %c0 GHz TSC %c1 %c3 %c6 %c7 %pc2 %pc3 %pc6 %pc7 0.27 1.29 2.29 0.95 0.02 0.00 98.77 20.23 0.00 77.41 0.00 0.25 1.24 2.29 0.98 0.02 0.00 98.75 20.34 0.03 77.74 0.00 0.27 1.22 2.29 0.54 0.00 0.00 99.18 20.64 0.00 77.70 0.00 0.26 1.22 2.29 1.22 0.00 0.00 98.52 20.22 0.00 77.74 0.00 0.26 1.38 2.29 0.78 0.02 0.00 98.95 20.51 0.05 77.56 0.00 ^C i# ./turbostat.new -s %c0 GHz TSC %c1 %c3 %c6 %c7 %pc2 %pc3 %pc6 %pc7 0.27 1.20 2.29 0.24 0.01 0.00 99.49 20.58 0.00 78.20 0.00 0.27 1.22 2.29 0.25 0.00 0.00 99.48 20.79 0.00 77.85 0.00 0.27 1.20 2.29 0.25 0.02 0.00 99.46 20.71 0.03 77.89 0.00 0.28 1.26 2.29 0.25 0.01 0.00 99.46 20.89 0.02 77.67 0.00 0.27 1.20 2.29 0.24 0.01 0.00 99.48 20.65 0.00 78.04 0.00 cc: Youquan Song <youquan.song@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-29tools turbostat: add summary optionLen Brown
turbostat -s cuts down on the amount of output, per user request. also treak some output whitespace and the man page. Signed-off-by: Len Brown <len.brown@intel.com>
2012-01-18Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux This includes initial support for the recently published ACPI 5.0 spec. In particular, support for the "hardware-reduced" bit that eliminates the dependency on legacy hardware. APEI has patches resulting from testing on real hardware. Plus other random fixes. * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (52 commits) acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec intel_idle: Split up and provide per CPU initialization func ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2 ACPI processor: Remove unneeded cpuidle_unregister_driver call intel idle: Make idle driver more robust intel_idle: Fix a cast to pointer from integer of different size warning in intel_idle ACPI: kernel-parameters.txt : Add intel_idle.max_cstate intel_idle: remove redundant local_irq_disable() call ACPI processor: Fix error path, also remove sysdev link ACPI: processor: fix acpi_get_cpuid for UP processor intel_idle: fix API misuse ACPI APEI: Convert atomicio routines ACPI: Export interfaces for ioremapping/iounmapping ACPI registers ACPI: Fix possible alignment issues with GAS 'address' references ACPI, ia64: Use SRAT table rev to use 8bit or 16/32bit PXM fields (ia64) ACPI, x86: Use SRAT table rev to use 8bit or 32bit PXM fields (x86/x86-64) ACPI: Store SRAT table revision ACPI, APEI, Resolve false conflict between ACPI NVS and APEI ACPI, Record ACPI NVS regions ACPI, APEI, EINJ, Refine the fix of resource conflict ...
2012-01-18Merge branches 'einj', 'intel_idle', 'misc', 'srat' and 'turbostat-ivb' into ↵Len Brown
release
2011-12-15tools/power turbostat: update fields in manpageArun Thomas
Field names were shortened: "pkg" is now "pk", "core" is now "cr" Signed-off-by: Arun Thomas <arun.thomas@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-11-18tools turbostat: recognize and run properly on IVBLen Brown
Signed-off-by: Len Brown <len.brown@intel.com>
2011-11-07Merge branches 'acpi', 'idle', 'mrst-pmu' and 'pm-tools' into nextLen Brown
2011-08-02tools/power turbostat: fit output into 80 columns on snb-epLen Brown
Reduce columns for package number to 1. If you can afford more than 9 packages, you can also afford a terminal with more than 80 columns:-) Also shave a column also off the package C-states Signed-off-by: Len Brown <len.brown@intel.com>
2011-07-16tools/power x86_energy_perf_policy: fix print of uninitialized stringLen Brown
Looks like I was going to stick the brand string in the verbose ouput, but didn't get around to it. Signed-off-by: Len Brown <len.brown@intel.com>
2011-07-04tools/power turbostat: less verbose debuggingLen Brown
dump only the counters which are active Signed-off-by: Len Brown <len.brown@intel.com>
2011-04-26Merge branch 'master' into for-nextJiri Kosina
Fast-forwarded to current state of Linus' tree as there are patches to be applied for files that didn't exist on the old branch.
2011-04-10treewide: remove extra semicolonsJustin P. Mattock
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-02-11tools: turbostat: style updatesLen Brown
Follow kernel coding style traditions more closely. Delete typedef, re-name "per cpu counters" to simply be counters etc. This patch changes no functionality. Suggested-by: Thiago Farina <tfransosi@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
2011-02-11tools: turbostat: fix bitwise and operandThomas Renninger
bug could cause false positive on indicating presence of invarient TSC or APERF support. Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12Merge branches 'turbostat' and 'x86_energy_perf_policy' into toolsLen Brown
2011-01-12tools: create power/x86/x86_energy_perf_policyLen Brown
MSR_IA32_ENERGY_PERF_BIAS first became available on Westmere Xeon. It is implemented in all Sandy Bridge processors -- mobile, desktop and server. It is expected to become increasingly important in subsequent generations. x86_energy_perf_policy is a user-space utility to set the hardware energy vs performance policy hint in the processor. Most systems would benefit from "x86_energy_perf_policy normal" at system startup, as the hardware default is maximum performance at the expense of energy efficiency. See x86_energy_perf_policy.8 man page for more information. Background: Linux-2.6.36 added "epb" to /proc/cpuinfo to indicate if an x86 processor supports MSR_IA32_ENERGY_PERF_BIAS, without actually modifying the MSR. In March, 2010, Venkatesh Pallipadi proposed a small driver that programmed MSR_IA32_ENERGY_PERF_BIAS, based on the cpufreq governor in use. It also offered a boot-time cmdline option to override. http://lkml.org/lkml/2010/3/4/457 But hiding the hardware policy behind the governor choice was deemed "kinda icky". In June, 2010, I proposed a generic user/kernel API to generalize the power/performance policy trade-off. "RFC: /sys/power/policy_preference" http://lkml.org/lkml/2010/6/16/399 That is my preference for implementing this capability, but I received no support on the list. So in September, 2010, I sent x86_energy_perf_policy.c to LKML, a user-space utility that scribbles directly to the MSR. http://lkml.org/lkml/2010/9/28/246 Here is that same utility, after responding to some review feedback, to live in tools/power/, where it is easily found. Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12tools: create power/x86/turbostatLen Brown
turbostat is a Linux tool to observe proper operation of Intel(R) Turbo Boost Technology. turbostat displays the actual processor frequency on x86 processors that include APERF and MPERF MSRs. Note that turbostat is of limited utility on Linux kernels 2.6.29 and older, as acpi_cpufreq cleared APERF/MPERF up through that release. On Intel Core i3/i5/i7 (Nehalem) and newer processors, turbostat also displays residency in idle power saving states, which are necessary for diagnosing any cpuidle issues that may have an effect on turbo-mode. See the turbostat.8 man page for example usage. Signed-off-by: Len Brown <len.brown@intel.com>