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McKenney" , Peter Zijlstra , Phil Auld , Steven Rostedt , Thomas Gleixner , Valentin Schneider , Vlastimil Babka , linux-doc@vger.kernel.org References: <20250809094247.8384-1-frederic@kernel.org> <20260324153823.VKwebBuG@linutronix.de> Content-Language: en-US From: Waiman Long In-Reply-To: <20260324153823.VKwebBuG@linutronix.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 On 3/24/26 11:38 AM, Sebastian Andrzej Siewior wrote: > On 2025-08-09 11:42:47 [+0200], Frederic Weisbecker wrote: > … >> --- /dev/null >> +++ b/Documentation/admin-guide/cpu-isolation.rst >> @@ -0,0 +1,338 @@ > … >> +CPUSET configuration (cgroup v2) >> +-------------------------------- >> + >> +Assuming cgroup v2 is mounted to /sys/fs/cgroup, the following script >> +isolates CPU 7 from scheduler domains. >> + >> + cd /sys/fs/cgroup >> + # Activate the cpuset subsystem >> + echo +cpuset > cgroup.subtree_control >> + # Create partition to be isolated >> + mkdir test >> + cd test >> + echo +cpuset > cgroup.subtree_control >> + # Isolate CPU 7 >> + echo 7 > cpuset.cpus >> + echo "isolated" > cpuset.cpus.partition > while looking at this again, shouldn't you also do > echo 7 > cpuset.cpus.exclusive > > to ensure the CPU isn't used somewhere else? For backport compatibility, the use of cpuset.cpus.exclusive is optional for creating a local partition underneath the cgroup root. The example should still work without setting cpuset.cpus.exclusive. Cheers, Longman