linux.git/tools/power, branch v6.1.168

tools/power cpupower: Reset errno before strtoull()

2026-03-04T12:20:13+00:00

[ Upstream commit f9bd3762cf1bd0c2465f2e6121b340883471d1bf ]

cpuidle_state_get_one_value() never cleared errno before calling
strtoull(), so a prior ERANGE caused every cpuidle counter read to
return zero. Reset errno to 0 before the conversion so each sysfs read
is evaluated independently.

Link: https://lore.kernel.org/r/20251201121745.3776703-1-kaushlendra.kumar@intel.com
Signed-off-by: Kaushlendra Kumar 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

tools/power x86_energy_perf_policy: Prefer driver HWP limits

2025-12-06T21:12:17+00:00

[ Upstream commit 2734fdbc9bb8a3aeb309ba0d62212d7f53f30bc7 ]

When we are successful in using cpufreq min/max limits,
skip setting the raw MSR limits entirely.

This is necessary to avoid undoing any modification that
the cpufreq driver makes to our sysfs request.

eg. intel_pstate may take our request for a limit
that is valid according to HWP.CAP.MIN/MAX and clip
it to be within the range available in PLATFORM_INFO.

Signed-off-by: Len Brown 
Signed-off-by: Sasha Levin

tools/power x86_energy_perf_policy: Enhance HWP enable

2025-12-06T21:12:17+00:00

[ Upstream commit c97c057d357c4b39b153e9e430bbf8976e05bd4e ]

On enabling HWP, preserve the reserved bits in MSR_PM_ENABLE.

Also, skip writing the MSR_PM_ENABLE if HWP is already enabled.

Signed-off-by: Len Brown 
Signed-off-by: Sasha Levin

tools/power x86_energy_perf_policy: Fix incorrect fopen mode usage

2025-12-06T21:12:17+00:00

[ Upstream commit 62127655b7ab7b8c2997041aca48a81bf5c6da0c ]

The fopen_or_die() function was previously hardcoded
to open files in read-only mode ("r"), ignoring the
mode parameter passed to it. This patch corrects
fopen_or_die() to use the provided mode argument,
allowing for flexible file access as intended.

Additionally, the call to fopen_or_die() in
err_on_hypervisor() incorrectly used the mode
"ro", which is not a valid fopen mode. This is
fixed to use the correct "r" mode.

Signed-off-by: Kaushlendra Kumar 
Signed-off-by: Len Brown 
Signed-off-by: Sasha Levin

tools/cpupower: Fix incorrect size in cpuidle_state_disable()

2025-12-06T21:12:17+00:00

[ Upstream commit 23199d2aa6dcaf6dd2da772f93d2c94317d71459 ]

Fix incorrect size parameter passed to cpuidle_state_write_file() in
cpuidle_state_disable().

The function was incorrectly using sizeof(disable) which returns the
size of the unsigned int variable (4 bytes) instead of the actual
length of the string stored in the 'value' buffer.

Since 'value' is populated with snprintf() to contain the string
representation of the disable value, we should use the length
returned by snprintf() to get the correct string length for
writing to the sysfs file.

This ensures the correct number of bytes is written to the cpuidle
state disable file in sysfs.

Link: https://lore.kernel.org/r/20250917050820.1785377-1-kaushlendra.kumar@intel.com
Signed-off-by: Kaushlendra Kumar 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

tools/cpupower: fix error return value in cpupower_write_sysfs()

2025-12-06T21:12:16+00:00

[ Upstream commit 57b100d4cf14276e0340eecb561005c07c129eb8 ]

The cpupower_write_sysfs() function currently returns -1 on
write failure, but the function signature indicates it should
return an unsigned int. Returning -1 from an unsigned function
results in a large positive value rather than indicating
an error condition.

Fix this by returning 0 on failure, which is more appropriate
for an unsigned return type and maintains consistency with typical
success/failure semantics where 0 indicates failure and non-zero
indicates success (bytes written).

Link: https://lore.kernel.org/r/20250828063000.803229-1-kaushlendra.kumar@intel.com
Signed-off-by: Kaushlendra Kumar 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

pm: cpupower: Fix the snapshot-order of tsc,mperf, clock in mperf_stop()

2025-08-28T14:25:54+00:00

[ Upstream commit cda7ac8ce7de84cf32a3871ba5f318aa3b79381e ]

In the function mperf_start(), mperf_monitor snapshots the time, tsc
and finally the aperf,mperf MSRs. However, this order of snapshotting
in is reversed in mperf_stop(). As a result, the C0 residency (which
is computed as delta_mperf * 100 / delta_tsc) is under-reported on
CPUs that is 100% busy.

Fix this by snapshotting time, tsc and then aperf,mperf in
mperf_stop() in the same order as in mperf_start().

Link: https://lore.kernel.org/r/20250612122355.19629-2-gautham.shenoy@amd.com
Signed-off-by: Gautham R. Shenoy 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

pm: cpupower: bench: Prevent NULL dereference on malloc failure

2025-04-25T08:43:27+00:00

[ Upstream commit 208baa3ec9043a664d9acfb8174b332e6b17fb69 ]

If malloc returns NULL due to low memory, 'config' pointer can be NULL.
Add a check to prevent NULL dereference.

Link: https://lore.kernel.org/r/20250219122715.3892223-1-quic_zhonhan@quicinc.com
Signed-off-by: Zhongqiu Han 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

cpupower: fix TSC MHz calculation

2025-02-21T12:49:00+00:00

[ Upstream commit 9d6c0e58514f8b57cd9c2c755e41623d6a966025 ]

Commit 'cpupower: Make TSC read per CPU for Mperf monitor' (c2adb1877b7)
changes TSC counter reads per cpu, but left time diff global (from start
of all cpus to end of all cpus), thus diff(time) is too large for a
cpu's tsc counting, resulting in far less than acutal TSC_Mhz and thus
`cpupower monitor` showing far less than actual cpu realtime frequency.

/proc/cpuinfo shows frequency:
cat /proc/cpuinfo | egrep -e 'processor' -e 'MHz'
...
processor : 171
cpu MHz   : 4108.498
...

before fix (System 100% busy):
    | Mperf              || Idle_Stats
 CPU| C0   | Cx   | Freq  || POLL | C1   | C2
 171|  0.77| 99.23|  2279||  0.00|  0.00|  0.00

after fix (System 100% busy):
    | Mperf              || Idle_Stats
 CPU| C0   | Cx   | Freq  || POLL | C1   | C2
 171|  0.46| 99.54|  4095||  0.00|  0.00|  0.00

Fixes: c2adb1877b76 ("cpupower: Make TSC read per CPU for Mperf monitor")
Signed-off-by: He Rongguang 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

tools/power/cpupower: Fix Pstate frequency reporting on AMD Family 1Ah CPUs

2024-07-25T07:49:08+00:00

[ Upstream commit 43cad521c6d228ea0c51e248f8e5b3a6295a2849 ]

Update cpupower's P-State frequency calculation and reporting with AMD
Family 1Ah+ processors, when using the acpi-cpufreq driver. This is due
to a change in the PStateDef MSR layout in AMD Family 1Ah+.

Tested on 4th and 5th Gen AMD EPYC system

Signed-off-by: Ananth Narayan 
Signed-off-by: Dhananjay Ugwekar 
Reviewed-by: Mario Limonciello 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin