[PATCH 18/33] cpuset: Remove cpuset_cpu_is_isolated()

Frederic Weisbecker
2025-10-13T20:34:22Z

The set of cpuset isolated CPUs is now included in HK_TYPE_DOMAIN
housekeeping cpumask. There is no usecase left interested in just
checking what is isolated by cpuset and not by the isolcpus= kernel
boot parameter.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
---
include/linux/cpuset.h | 6 ------
include/linux/sched/isolation.h | 3 +--
kernel/cgroup/cpuset.c | 12 ------------
3 files changed, 1 insertion(+), 20 deletions(-)

diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 051d36fec578..a10775a4f702 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -78,7 +78,6 @@ extern void cpuset_lock(void);
extern void cpuset_unlock(void);
extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
extern bool cpuset_cpus_allowed_fallback(struct task_struct *p);
-extern bool cpuset_cpu_is_isolated(int cpu);
extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
#define cpuset_current_mems_allowed (current->mems_allowed)
void cpuset_init_current_mems_allowed(void);
@@ -208,11 +207,6 @@ static inline bool cpuset_cpus_allowed_fallback(struct task_struct *p)
return false;
}

-static inline bool cpuset_cpu_is_isolated(int cpu)
-{
- return false;
-}
-
static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
{
return node_possible_map;
diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h
index 94d5c835121b..0f50c152cf68 100644
--- a/include/linux/sched/isolation.h
+++ b/include/linux/sched/isolation.h
@@ -76,8 +76,7 @@ static inline bool housekeeping_cpu(int cpu, enum hk_type type)
static inline bool cpu_is_isolated(int cpu)
{
return !housekeeping_test_cpu(cpu, HK_TYPE_DOMAIN) ||
- !housekeeping_test_cpu(cpu, HK_TYPE_TICK) ||
- cpuset_cpu_is_isolated(cpu);
+ !housekeeping_test_cpu(cpu, HK_TYPE_TICK);
}

#endif /* _LINUX_SCHED_ISOLATION_H */
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index ea102e4695a5..e19d3375a4ec 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -29,7 +29,6 @@
#include <linux/mempolicy.h>
#include <linux/mm.h>
#include <linux/memory.h>
-#include <linux/export.h>
#include <linux/rcupdate.h>
#include <linux/sched.h>
#include <linux/sched/deadline.h>
@@ -1405,17 +1404,6 @@ static void update_housekeeping_cpumask(bool isolcpus_updated)
WARN_ON_ONCE(ret < 0);
}

-/**
- * cpuset_cpu_is_isolated - Check if the given CPU is isolated
- * @cpu: the CPU number to be checked
- * Return: true if CPU is used in an isolated partition, false otherwise
- */
-bool cpuset_cpu_is_isolated(int cpu)
-{
- return cpumask_test_cpu(cpu, isolated_cpus);
-}
-EXPORT_SYMBOL_GPL(cpuset_cpu_is_isolated);
-
/**
* rm_siblings_excl_cpus - Remove exclusive CPUs that are used by sibling cpusets
* @parent: Parent cpuset containing all siblings
--
2.51.0