From 75a086d77a79f72292affa816c5789d40b86a171 Mon Sep 17 00:00:00 2001
From: Patrick Bellasi <patrick.bellasi@arm.com>
Date: Fri, 26 Aug 2016 16:29:43 +0100
Subject: [PATCH] cgroups: add support for CPUs isolation
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
---
devlib/module/cgroups.py | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/devlib/module/cgroups.py b/devlib/module/cgroups.py
index b146abb..ad50c44 100644
--- a/devlib/module/cgroups.py
+++ b/devlib/module/cgroups.py
@@ -388,3 +388,38 @@ class CgroupsModule(Module):
'cgroups_tasks_move {} {} {}'.format(srcg, dstg, exclude),
as_root=True)
+ def isolate(self, cpus, exclude=[]):
+ """
+ Remove all userspace tasks from specified CPUs.
+
+ A list of CPUs can be specified where we do not want userspace tasks
+ running. This functions creates a sandbox cpuset CGroup where all
+ user-space tasks and not-pinned kernel-space tasks are moved into.
+ This should allows to isolate the specified CPUs which will not get
+ tasks running unless explicitely moved into the isolated group.
+
+ :param cpus: the list of CPUs to isolate
+ :type cpus: list(int)
+
+ :return: the (sandbox, isolated) tuple, where:
+ sandbox is the CGroup of sandboxed CPUs
+ isolated is the CGroup of isolated CPUs
+ """
+ all_cpus = set(range(self.target.number_of_cpus))
+ sbox_cpus = list(all_cpus - set(cpus))
+ isol_cpus = list(all_cpus - set(sbox_cpus))
+
+ # Create Sandbox and Isolated cpuset CGroups
+ cpuset = self.controller('cpuset')
+ sbox_cg = cpuset.cgroup('/DEVLIB_SBOX')
+ isol_cg = cpuset.cgroup('/DEVLIB_ISOL')
+
+ # Set CPUs for Sandbox and Isolated CGroups
+ sbox_cg.set(cpus=sbox_cpus, mems=0)
+ isol_cg.set(cpus=isol_cpus, mems=0)
+
+ # Move all currently running tasks to the Sandbox CGroup
+ cpuset.move_all_tasks_to('/DEVLIB_SBOX', exclude)
+
+ return sbox_cg, isol_cg
+