[PATCH v2] tools/cpupower: Choose base_cpu to display default cpupower details

From: Saket Kumar Bhaskar
Date: Wed Nov 23 2022 - 03:23:38 EST


The default output of cpupower info utils shows unexpected output
when CPU 0 is disabled.

Considering a case where CPU 0 is disabled, output of cpupower idle-info:

Before change:
cpupower idle-info
CPUidle driver: pseries_idle
CPUidle governor: menu
analyzing CPU 0:
*is offline

After change:
./cpupower idle-info
CPUidle driver: pseries_idle
CPUidle governor: menu
analyzing CPU 50:

Number of idle states: 2
Available idle states: snooze CEDE
snooze:
Flags/Description: snooze
Latency: 0
Usage: 101748
Duration: 2724058
CEDE:
Flags/Description: CEDE
Latency: 12
Usage: 270004
Duration: 283019526849

If -c option is not passed, CPU 0 was chosen as the default chosen CPU to
display details. However when CPU 0 is offline, it results in showing
unexpected output. This commit chooses the base_cpu
instead of CPU 0, hence keeping the output more relevant in all cases.
The base_cpu is the number of CPU on which the calling thread is
currently executing.

Signed-off-by: Saket Kumar Bhaskar <skb99@xxxxxxxxxxxxxxxxxx>
---
tools/power/cpupower/utils/cpufreq-info.c | 4 ++--
tools/power/cpupower/utils/cpuidle-info.c | 4 ++--
tools/power/cpupower/utils/cpupower-info.c | 4 ++--
3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/power/cpupower/utils/cpufreq-info.c b/tools/power/cpupower/utils/cpufreq-info.c
index 0646f615fe2d..c96b77365c63 100644
--- a/tools/power/cpupower/utils/cpufreq-info.c
+++ b/tools/power/cpupower/utils/cpufreq-info.c
@@ -572,9 +572,9 @@ int cmd_freq_info(int argc, char **argv)

ret = 0;

- /* Default is: show output of CPU 0 only */
+ /* Default is: show output of base_cpu only */
if (bitmask_isallclear(cpus_chosen))
- bitmask_setbit(cpus_chosen, 0);
+ bitmask_setbit(cpus_chosen, base_cpu);

switch (output_param) {
case -1:
diff --git a/tools/power/cpupower/utils/cpuidle-info.c b/tools/power/cpupower/utils/cpuidle-info.c
index f2b202c5552a..44126a87fa7a 100644
--- a/tools/power/cpupower/utils/cpuidle-info.c
+++ b/tools/power/cpupower/utils/cpuidle-info.c
@@ -176,9 +176,9 @@ int cmd_idle_info(int argc, char **argv)
cpuidle_exit(EXIT_FAILURE);
}

- /* Default is: show output of CPU 0 only */
+ /* Default is: show output of base_cpu only */
if (bitmask_isallclear(cpus_chosen))
- bitmask_setbit(cpus_chosen, 0);
+ bitmask_setbit(cpus_chosen, base_cpu);

if (output_param == 0)
cpuidle_general_output();
diff --git a/tools/power/cpupower/utils/cpupower-info.c b/tools/power/cpupower/utils/cpupower-info.c
index 06345b543786..18fd7751f509 100644
--- a/tools/power/cpupower/utils/cpupower-info.c
+++ b/tools/power/cpupower/utils/cpupower-info.c
@@ -67,9 +67,9 @@ int cmd_info(int argc, char **argv)
if (!params.params)
params.params = 0x7;

- /* Default is: show output of CPU 0 only */
+ /* Default is: show output of base_cpu only */
if (bitmask_isallclear(cpus_chosen))
- bitmask_setbit(cpus_chosen, 0);
+ bitmask_setbit(cpus_chosen, base_cpu);

/* Add more per cpu options here */
if (!params.perf_bias)
--
2.31.1