From 83ee596ef28811048d5a39fdb319fc3f36a5f848 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaroslav=20=C5=A0karvada?= <jskarvad@redhat.com>
Date: Thu, 16 Dec 2021 01:26:16 +0100
Subject: [PATCH] cpu_partitioning: fixed no_balance_cores on newer kernels
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I.e. kernels without the SD_LOAD_BALANCE.

Resolves: rhbz#1874596

Signed-off-by: Jaroslav Škarvada <jskarvad@redhat.com>
---
 profiles/cpu-partitioning/script.sh  | 36 ----------------------------
 profiles/cpu-partitioning/tuned.conf |  4 +++-
 2 files changed, 3 insertions(+), 37 deletions(-)

diff --git a/profiles/cpu-partitioning/script.sh b/profiles/cpu-partitioning/script.sh
index 8677050..84e04fd 100755
--- a/profiles/cpu-partitioning/script.sh
+++ b/profiles/cpu-partitioning/script.sh
@@ -2,38 +2,6 @@
 
 . /usr/lib/tuned/functions
 
-no_balance_cpus_file=$STORAGE/no-balance-cpus.txt
-
-change_sd_balance_bit()
-{
-    local set_bit=$1
-    local flags_cur=
-    local file=
-    local cpu=
-
-    for cpu in $(cat $no_balance_cpus_file); do
-        for file in $(find /proc/sys/kernel/sched_domain/cpu$cpu -name flags -print); do
-            flags_cur=$(cat $file)
-            if [ $set_bit -eq 1 ]; then
-                flags_cur=$((flags_cur | 0x1))
-            else
-                flags_cur=$((flags_cur & 0xfffe))
-            fi
-            echo $flags_cur > $file
-        done
-    done
-}
-
-disable_balance_domains()
-{
-    change_sd_balance_bit 0
-}
-
-enable_balance_domains()
-{
-    change_sd_balance_bit 1
-}
-
 start() {
     mkdir -p "${TUNED_tmpdir}/etc/systemd"
     mkdir -p "${TUNED_tmpdir}/usr/lib/dracut/hooks/pre-udev"
@@ -41,9 +9,6 @@ start() {
     cp 00-tuned-pre-udev.sh "${TUNED_tmpdir}/usr/lib/dracut/hooks/pre-udev/"
     setup_kvm_mod_low_latency
     disable_ksm
-
-    echo "$TUNED_no_balance_cores_expanded" | sed 's/,/ /g' > $no_balance_cpus_file
-    disable_balance_domains
     return "$?"
 }
 
@@ -53,7 +18,6 @@ stop() {
         teardown_kvm_mod_low_latency
         enable_ksm
     fi
-    enable_balance_domains
     return "$?"
 }
 
diff --git a/profiles/cpu-partitioning/tuned.conf b/profiles/cpu-partitioning/tuned.conf
index 842e2bd..979e40b 100644
--- a/profiles/cpu-partitioning/tuned.conf
+++ b/profiles/cpu-partitioning/tuned.conf
@@ -35,6 +35,8 @@ no_balance_cores_expanded=${f:cpulist_unpack:${no_balance_cores}}
 # Fail if isolated_cores contains CPUs which are not online
 assert2=${f:assertion:isolated_cores contains online CPU(s):${isolated_cores_expanded}:${isolated_cores_online_expanded}}
 
+cmd_isolcpus=${f:regex_search_ternary:${no_balance_cores}:\s*[0-9]: isolcpus=${no_balance_cores}:}
+
 [sysctl]
 kernel.hung_task_timeout_secs = 600
 kernel.nmi_watchdog = 0
@@ -66,4 +68,4 @@ priority=10
 initrd_remove_dir=True
 initrd_dst_img=tuned-initrd.img
 initrd_add_dir=${tmpdir}
-cmdline_cpu_part=+nohz=on nohz_full=${isolated_cores} rcu_nocbs=${isolated_cores} tuned.non_isolcpus=${not_isolated_cpumask} intel_pstate=disable nosoftlockup
+cmdline_cpu_part=+nohz=on${cmd_isolcpus} nohz_full=${isolated_cores} rcu_nocbs=${isolated_cores} tuned.non_isolcpus=${not_isolated_cpumask} intel_pstate=disable nosoftlockup