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-rw-r--r--tools/power/cpupower/man/cpupower-idle-info.13
-rw-r--r--tools/power/cpupower/man/cpupower-idle-set.171
-rw-r--r--tools/power/cpupower/utils/helpers/sysfs.c4
3 files changed, 75 insertions, 3 deletions
diff --git a/tools/power/cpupower/man/cpupower-idle-info.1 b/tools/power/cpupower/man/cpupower-idle-info.1
index 4178effd9e99..7b3646adb92f 100644
--- a/tools/power/cpupower/man/cpupower-idle-info.1
+++ b/tools/power/cpupower/man/cpupower-idle-info.1
@@ -87,4 +87,5 @@ Thomas Renninger <trenn@suse.de>
.fi
.SH "SEE ALSO"
.LP
-cpupower(1), cpupower\-monitor(1), cpupower\-info(1), cpupower\-set(1)
+cpupower(1), cpupower\-monitor(1), cpupower\-info(1), cpupower\-set(1),
+cpupower\-idle\-set(1)
diff --git a/tools/power/cpupower/man/cpupower-idle-set.1 b/tools/power/cpupower/man/cpupower-idle-set.1
new file mode 100644
index 000000000000..6b1607272a5b
--- /dev/null
+++ b/tools/power/cpupower/man/cpupower-idle-set.1
@@ -0,0 +1,71 @@
+.TH "CPUPOWER-IDLE-SET" "1" "0.1" "" "cpupower Manual"
+.SH "NAME"
+.LP
+cpupower idle\-set \- Utility to set cpu idle state specific kernel options
+.SH "SYNTAX"
+.LP
+cpupower [ \-c cpulist ] idle\-info [\fIoptions\fP]
+.SH "DESCRIPTION"
+.LP
+The cpupower idle\-set subcommand allows to set cpu idle, also called cpu
+sleep state, specific options offered by the kernel. One example is disabling
+sleep states. This can be handy for power vs performance tuning.
+.SH "OPTIONS"
+.LP
+.TP
+\fB\-d\fR \fB\-\-disable\fR
+Disable a specific processor sleep state.
+.TP
+\fB\-e\fR \fB\-\-enable\fR
+Enable a specific processor sleep state.
+
+.SH "REMARKS"
+.LP
+Cpuidle Governors Policy on Disabling Sleep States
+
+.RS 4
+Depending on the used cpuidle governor, implementing the kernel policy
+how to choose sleep states, subsequent sleep states on this core, might get
+disabled as well.
+
+There are two cpuidle governors ladder and menu. While the ladder
+governor is always available, if CONFIG_CPU_IDLE is selected, the
+menu governor additionally requires CONFIG_NO_HZ.
+
+The behavior and the effect of the disable variable depends on the
+implementation of a particular governor. In the ladder governor, for
+example, it is not coherent, i.e. if one is disabling a light state,
+then all deeper states are disabled as well. Likewise, if one enables a
+deep state but a lighter state still is disabled, then this has no effect.
+.RE
+.LP
+Disabling the Lightest Sleep State may not have any Affect
+
+.RS 4
+If criteria are not met to enter deeper sleep states and the lightest sleep
+state is chosen when idle, the kernel may still enter this sleep state,
+irrespective of whether it is disabled or not. This is also reflected in
+the usage count of the disabled sleep state when using the cpupower idle-info
+command.
+.RE
+.LP
+Selecting specific CPU Cores
+
+.RS 4
+By default processor sleep states of all CPU cores are set. Please refer
+to the cpupower(1) manpage in the \-\-cpu option section how to disable
+C-states of specific cores.
+.RE
+.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),
+cpupower\-idle\-info(1)
diff --git a/tools/power/cpupower/utils/helpers/sysfs.c b/tools/power/cpupower/utils/helpers/sysfs.c
index 5cdc600e8152..851c7a16ca49 100644
--- a/tools/power/cpupower/utils/helpers/sysfs.c
+++ b/tools/power/cpupower/utils/helpers/sysfs.c
@@ -278,7 +278,7 @@ static char *sysfs_idlestate_get_one_string(unsigned int cpu,
int sysfs_is_idlestate_disabled(unsigned int cpu,
unsigned int idlestate)
{
- if (sysfs_get_idlestate_count(cpu) < idlestate)
+ if (sysfs_get_idlestate_count(cpu) <= idlestate)
return -1;
if (!sysfs_idlestate_file_exists(cpu, idlestate,
@@ -303,7 +303,7 @@ int sysfs_idlestate_disable(unsigned int cpu,
char value[SYSFS_PATH_MAX];
int bytes_written;
- if (sysfs_get_idlestate_count(cpu) < idlestate)
+ if (sysfs_get_idlestate_count(cpu) <= idlestate)
return -1;
if (!sysfs_idlestate_file_exists(cpu, idlestate,