[PATCH] tools/power: intel_pstate_tracer: avoid optional imports for help

From: Yousef Alhouseen

Date: Wed Jun 24 2026 - 08:32:21 EST


intel_pstate_tracer imports Gnuplot and numpy before parsing command-line
options. As a result, even "-h" fails if those optional runtime modules are
not installed.

Move the imports to the paths that need them. This lets the help and
invalid-argument paths describe usage without requiring plotting/data
dependencies. While there, fix a typo in the help text and matching
comments.

Signed-off-by: Yousef Alhouseen <alhouseenyousef@xxxxxxxxx>
---
.../intel_pstate_tracer/intel_pstate_tracer.py | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py b/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py
index 38cfbdcde..64001bc80 100755
--- a/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py
+++ b/tools/power/x86/intel_pstate_tracer/intel_pstate_tracer.py
@@ -32,8 +32,6 @@ import re
import signal
import sys
import getopt
-import Gnuplot
-from numpy import *
from decimal import *

__author__ = "Srinivas Pandruvada"
@@ -88,8 +86,8 @@ def print_help(driver_name):
print(' kbytes: Kilo bytes of memory per CPU to allocate to the trace buffer. Default: 10240')
print(' Output:')
print(' If not already present, creates a "results/test_name" folder in the current working directory with:')
- print(' cpu.csv - comma seperated values file with trace contents and some additional calculations.')
- print(' cpu???.csv - comma seperated values file for CPU number ???.')
+ print(' cpu.csv - comma separated values file with trace contents and some additional calculations.')
+ print(' cpu???.csv - comma separated values file for CPU number ???.')
print(' *.png - a variety of PNG format plot files created from the trace contents and the additional calculations.')
print(' Notes:')
print(' Avoid the use of _ (underscore) in test names, because in gnuplot it is a subscript directive.')
@@ -295,6 +293,8 @@ def common_all_gnuplot_settings(output_png):
def common_gnuplot_settings():
""" common gnuplot settings. """

+ import Gnuplot
+
g_plot = Gnuplot.Gnuplot(persist=1)
# The following line is for rigor only. It seems to be assumed for .csv files
g_plot('set datafile separator \",\"')
@@ -343,7 +343,7 @@ def store_csv(cpu_int, time_pre_dec, time_post_dec, core_busy, scaled, _from, _t
graph_data_present = True;

def split_csv(current_max_cpu, cpu_mask):
- """ seperate the all csv file into per CPU csv files. """
+ """ separate the main csv file into per CPU csv files. """

if os.path.exists('cpu.csv'):
for index in range(0, current_max_cpu + 1):
@@ -482,7 +482,7 @@ def read_trace_data(filename, cpu_mask):
if cpu_int > current_max_cpu:
current_max_cpu = cpu_int
# End of for each trace line loop
-# Now seperate the main overall csv file into per CPU csv files.
+# Now separate the main overall csv file into per CPU csv files.
split_csv(current_max_cpu, cpu_mask)

def signal_handler(signal, frame):
@@ -508,8 +508,6 @@ if __name__ == "__main__":
valid1 = False
valid2 = False

- cpu_mask = zeros((MAX_CPUS,), dtype=int)
-
try:
opts, args = getopt.getopt(sys.argv[1:],"ht:i:c:n:m:",["help","trace_file=","interval=","cpu=","name=","memory="])
except getopt.GetoptError:
@@ -538,6 +536,10 @@ if __name__ == "__main__":
print_help('intel_pstate')
sys.exit()

+ from numpy import zeros
+
+ cpu_mask = zeros((MAX_CPUS,), dtype=int)
+
if cpu_list:
for p in re.split("[,]", cpu_list):
if int(p) < MAX_CPUS :
--
2.54.0