From c67e290cc0e5ac1e4b52a134866c7edfb7293c6f Mon Sep 17 00:00:00 2001
From: Michael Livshin <github@cmm.kakpryg.net>
Date: Sat, 1 Jul 2023 10:36:25 +0300
Subject: [PATCH] cpufreqctl: don't try writing to non-existent files (#533)

When you give "nosmt" to your kernel, you still get directories under
/sys that correspond to inactive hyperthreads, but there's nothing
writable inside those directories, which causes auto-cpufreq to
generate lots of logspam.
---
 scripts/cpufreqctl.sh | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/scripts/cpufreqctl.sh b/scripts/cpufreqctl.sh
index 8818d58..6704089 100755
--- a/scripts/cpufreqctl.sh
+++ b/scripts/cpufreqctl.sh
@@ -100,6 +100,12 @@ function driver () {
   cat $FLROOT/cpu0/cpufreq/scaling_driver
 }
 
+function write_value () {
+  if [ -w $FLNM ]; then
+    echo $VALUE > $FLNM
+  fi
+}
+
 function set_driver () {
   DRIVER=`driver`
   case $DRIVER in
@@ -136,7 +142,7 @@ function set_governor () {
     while [ $i -ne $cpucount ]
     do
       FLNM="$FLROOT/cpu"$i"/cpufreq/scaling_governor"
-      echo $VALUE > $FLNM
+      write_value
       i=`expr $i + 1`
     done
   else
@@ -178,7 +184,7 @@ function set_frequency () {
     while [ $i -ne $cpucount ]
     do
       FLNM="$FLROOT/cpu"$i"/cpufreq/scaling_setspeed"
-      echo $VALUE > $FLNM
+      write_value
       i=`expr $i + 1`
     done
   else
@@ -201,7 +207,7 @@ function set_frequency_min () {
     while [ $i -ne $cpucount ]
     do
       FLNM="$FLROOT/cpu"$i"/cpufreq/scaling_min_freq"
-      echo $VALUE > $FLNM
+      write_value
       i=`expr $i + 1`
     done
   else
@@ -224,7 +230,7 @@ function set_frequency_max () {
     while [ $i -ne $cpucount ]
     do
       FLNM="$FLROOT/cpu"$i"/cpufreq/scaling_max_freq"
-      echo $VALUE > $FLNM
+      write_value
       i=`expr $i + 1`
     done
   else
@@ -276,7 +282,7 @@ function set_energy_performance_preference () {
     while [ $i -ne $cpucount ]
     do
       FLNM="$FLROOT/cpu"$i"/cpufreq/energy_performance_preference"
-      echo $VALUE > $FLNM
+      write_value
       i=`expr $i + 1`
     done
   else