[PATCH 2/6] sched/deadline: Inform dl_task_can_attach() if the cpuset is exclusive

[Daniel Bristot de Oliveira]

In preparation for blocking SCHED_DEADLINE tasks on non-exclusive cpuset
if bandwidth control is enabled.

No functional changes.

Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ben Segall <bsegall@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Li Zefan <lizefan@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Valentin Schneider <valentin.schneider@xxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: cgroups@xxxxxxxxxxxxxxx
---
 include/linux/sched.h   | 2 +-
 kernel/cgroup/cpuset.c  | 5 ++++-
 kernel/sched/core.c     | 4 ++--
 kernel/sched/deadline.c | 3 ++-
 kernel/sched/sched.h    | 2 +-
 5 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 942b87f80cc7..9525fbe032c9 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1654,7 +1654,7 @@ current_restore_flags(unsigned long orig_flags, unsigned long flags)
 }
 
 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
-extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
+extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed, int exclusive);
 #ifdef CONFIG_SMP
 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 53c70c470a38..c6513dfabd3d 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -2132,6 +2132,7 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
 	struct cgroup_subsys_state *css;
 	struct cpuset *cs;
 	struct task_struct *task;
+	int exclusive;
 	int ret;
 
 	/* used later by cpuset_attach() */
@@ -2146,8 +2147,10 @@ static int cpuset_can_attach(struct cgroup_taskset *tset)
 	    (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
 		goto out_unlock;
 
+	exclusive = is_cpu_exclusive(cs);
+
 	cgroup_taskset_for_each(task, css, tset) {
-		ret = task_can_attach(task, cs->cpus_allowed);
+		ret = task_can_attach(task, cs->cpus_allowed, exclusive);
 		if (ret)
 			goto out_unlock;
 		ret = security_task_setscheduler(task);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f4aede34449c..5961a97541c2 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7124,7 +7124,7 @@ int cpuset_cpumask_can_shrink(const struct cpumask *cur,
 }
 
 int task_can_attach(struct task_struct *p,
-		    const struct cpumask *cs_cpus_allowed)
+		    const struct cpumask *cs_cpus_allowed, int exclusive)
 {
 	int ret = 0;
 
@@ -7143,7 +7143,7 @@ int task_can_attach(struct task_struct *p,
 	}
 
 	if (dl_task(p))
-		ret = dl_task_can_attach(p, cs_cpus_allowed);
+		ret = dl_task_can_attach(p, cs_cpus_allowed, exclusive);
 
 out:
 	return ret;
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index c97d2c707b98..943aa32cc1bc 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -2862,7 +2862,8 @@ bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
 }
 
 #ifdef CONFIG_SMP
-int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed)
+int dl_task_can_attach(struct task_struct *p,
+		const struct cpumask *cs_cpus_allowed, int exclusive)
 {
 	unsigned long flags, cap;
 	unsigned int dest_cpu;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index f5acb6c5ce49..54881d99cebd 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -337,7 +337,7 @@ extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
 extern bool __checkparam_dl(const struct sched_attr *attr);
 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
-extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
+extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed, int exclusive);
 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
 extern bool dl_cpu_busy(unsigned int cpu);
 
-- 
2.29.2