diff options
Diffstat (limited to 'tools/power/cpupower/man')
-rw-r--r-- | tools/power/cpupower/man/cpupower-frequency-info.1 | 4 | ||||
-rw-r--r-- | tools/power/cpupower/man/cpupower-frequency-set.1 | 4 | ||||
-rw-r--r-- | tools/power/cpupower/man/cpupower-idle-info.1 | 90 | ||||
-rw-r--r-- | tools/power/cpupower/man/cpupower-monitor.1 | 2 |
4 files changed, 93 insertions, 7 deletions
diff --git a/tools/power/cpupower/man/cpupower-frequency-info.1 b/tools/power/cpupower/man/cpupower-frequency-info.1 index bb60a8d1e45a..4a1918ea8f9c 100644 --- a/tools/power/cpupower/man/cpupower-frequency-info.1 +++ b/tools/power/cpupower/man/cpupower-frequency-info.1 @@ -1,4 +1,4 @@ -.TH "cpupower-frequency-info" "1" "0.1" "Mattia Dongili" "" +.TH "CPUPOWER\-FREQUENCY\-INFO" "1" "0.1" "" "cpupower Manual" .SH "NAME" .LP cpupower frequency\-info \- Utility to retrieve cpufreq kernel information @@ -50,8 +50,6 @@ Prints out information like provided by the /proc/cpufreq interface in 2.4. and \fB\-m\fR \fB\-\-human\fR human\-readable output for the \-f, \-w, \-s and \-y parameters. .TP -\fB\-h\fR \fB\-\-help\fR -Prints out the help screen. .SH "REMARKS" .LP By default only values of core zero are displayed. How to display settings of diff --git a/tools/power/cpupower/man/cpupower-frequency-set.1 b/tools/power/cpupower/man/cpupower-frequency-set.1 index 685f469093ad..3eacc8d03d1a 100644 --- a/tools/power/cpupower/man/cpupower-frequency-set.1 +++ b/tools/power/cpupower/man/cpupower-frequency-set.1 @@ -1,4 +1,4 @@ -.TH "cpupower-freqency-set" "1" "0.1" "Mattia Dongili" "" +.TH "CPUPOWER\-FREQUENCY\-SET" "1" "0.1" "" "cpupower Manual" .SH "NAME" .LP cpupower frequency\-set \- A small tool which allows to modify cpufreq settings. @@ -26,8 +26,6 @@ specific frequency to be set. Requires userspace governor to be available and lo \fB\-r\fR \fB\-\-related\fR modify all hardware-related CPUs at the same time .TP -\fB\-h\fR \fB\-\-help\fR -Prints out the help screen. .SH "REMARKS" .LP By default values are applied on all cores. How to modify single core diff --git a/tools/power/cpupower/man/cpupower-idle-info.1 b/tools/power/cpupower/man/cpupower-idle-info.1 new file mode 100644 index 000000000000..4178effd9e99 --- /dev/null +++ b/tools/power/cpupower/man/cpupower-idle-info.1 @@ -0,0 +1,90 @@ +.TH "CPUPOWER-IDLE-INFO" "1" "0.1" "" "cpupower Manual" +.SH "NAME" +.LP +cpupower idle\-info \- Utility to retrieve cpu idle kernel information +.SH "SYNTAX" +.LP +cpupower [ \-c cpulist ] idle\-info [\fIoptions\fP] +.SH "DESCRIPTION" +.LP +A tool which prints out per cpu idle information helpful to developers and interested users. +.SH "OPTIONS" +.LP +.TP +\fB\-f\fR \fB\-\-silent\fR +Only print a summary of all available C-states in the system. +.TP +\fB\-e\fR \fB\-\-proc\fR +deprecated. +Prints out idle information in old /proc/acpi/processor/*/power format. This +interface has been removed from the kernel for quite some time, do not let +further code depend on this option, best do not use it. + +.SH IDLE\-INFO DESCRIPTIONS +CPU sleep state statistics and descriptions are retrieved from sysfs files, +exported by the cpuidle kernel subsystem. The kernel only updates these +statistics when it enters or leaves an idle state, therefore on a very idle or +a very busy system, these statistics may not be accurate. They still provide a +good overview about the usage and availability of processor sleep states on +the platform. + +Be aware that the sleep states as exported by the hardware or BIOS and used by +the Linux kernel may not exactly reflect the capabilities of the +processor. This often is the case on the X86 architecture when the acpi_idle +driver is used. It is also possible that the hardware overrules the kernel +requests, due to internal activity monitors or other reasons. +On recent X86 platforms it is often possible to read out hardware registers +which monitor the duration of sleep states the processor resided in. The +cpupower monitor tool (cpupower\-monitor(1)) can be used to show real sleep +state residencies. Please refer to the architecture specific description +section below. + +.SH IDLE\-INFO ARCHITECTURE SPECIFIC DESCRIPTIONS +.SS "X86" +POLL idle state + +If cpuidle is active, X86 platforms have one special idle state. +The POLL idle state is not a real idle state, it does not save any +power. Instead, a busy\-loop is executed doing nothing for a short period of +time. This state is used if the kernel knows that work has to be processed +very soon and entering any real hardware idle state may result in a slight +performance penalty. + +There exist two different cpuidle drivers on the X86 architecture platform: + +"acpi_idle" cpuidle driver + +The acpi_idle cpuidle driver retrieves available sleep states (C\-states) from +the ACPI BIOS tables (from the _CST ACPI function on recent platforms or from +the FADT BIOS table on older ones). +The C1 state is not retrieved from ACPI tables. If the C1 state is entered, +the kernel will call the hlt instruction (or mwait on Intel). + +"intel_idle" cpuidle driver + +In kernel 2.6.36 the intel_idle driver was introduced. +It only serves recent Intel CPUs (Nehalem, Westmere, Sandybridge, Atoms or +newer). On older Intel CPUs the acpi_idle driver is still used (if the BIOS +provides C\-state ACPI tables). +The intel_idle driver knows the sleep state capabilities of the processor and +ignores ACPI BIOS exported processor sleep states tables. + +.SH "REMARKS" +.LP +By default only values of core zero are displayed. How to display settings of +other cores is described in the cpupower(1) manpage in the \-\-cpu option +section. +.SH REFERENCES +http://www.acpi.info/spec.htm +.SH "FILES" +.nf +\fI/sys/devices/system/cpu/cpu*/cpuidle/state*\fP +\fI/sys/devices/system/cpu/cpuidle/*\fP +.fi +.SH "AUTHORS" +.nf +Thomas Renninger <trenn@suse.de> +.fi +.SH "SEE ALSO" +.LP +cpupower(1), cpupower\-monitor(1), cpupower\-info(1), cpupower\-set(1) diff --git a/tools/power/cpupower/man/cpupower-monitor.1 b/tools/power/cpupower/man/cpupower-monitor.1 index d5cfa265c3d3..1141c2073719 100644 --- a/tools/power/cpupower/man/cpupower-monitor.1 +++ b/tools/power/cpupower/man/cpupower-monitor.1 @@ -107,7 +107,7 @@ Deepest package sleep states may in reality show up as machine/platform wide sleep states and can only be entered if all cores are idle. Look up Intel manuals (some are provided in the References section) for further details. -.SS "Ontario" "Liano" +.SS "Fam_12h" "Fam_14h" AMD laptop and desktop processor (family 12h and 14h) sleep state counters. The registers are accessed via PCI and therefore can still be read out while cores have been offlined. |