[PATCH 2/8] workqueue: Decouple HK_FLAG_WQ and HK_FLAG_DOMAIN cpumask fetch

[Frederic Weisbecker]

To prepare for supporting each feature of the housekeeping cpumask
toward cpuset, prepare each of the HK_FLAG_* entries to move to their
own cpumask with enforcing to fetch them individually. The new
constraint is that multiple HK_FLAG_* entries can't be mixed together
anymore in a single call to housekeeping cpumask().

This will later allow, for example, to runtime modify the cpulist passed
through "isolcpus=", "nohz_full=" and "rcu_nocbs=" kernel boot
parameters.

Reviewed-by: Juri Lelli <juri.lelli@xxxxxxxxxx>
Reviewed-by: Phil Auld <pauld@xxxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: Nitesh Lal <nilal@xxxxxxxxxx>
Cc: Nicolas Saenz <nsaenzju@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Zefan Li <lizefan.x@xxxxxxxxxxxxx>
Cc: Alex Belits <abelits@xxxxxxxxxxx>
Cc: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
Cc: Paul E. McKenney  <paulmck@xxxxxxxxxx>
---
 kernel/workqueue.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 33f1106b4f99..61ed310621ea 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -6006,13 +6006,13 @@ static void __init wq_numa_init(void)
 void __init workqueue_init_early(void)
 {
 	int std_nice[NR_STD_WORKER_POOLS] = { 0, HIGHPRI_NICE_LEVEL };
-	int hk_flags = HK_FLAG_DOMAIN | HK_FLAG_WQ;
 	int i, cpu;
 
 	BUILD_BUG_ON(__alignof__(struct pool_workqueue) < __alignof__(long long));
 
 	BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL));
-	cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(hk_flags));
+	cpumask_copy(wq_unbound_cpumask, housekeeping_cpumask(HK_FLAG_WQ));
+	cpumask_and(wq_unbound_cpumask, wq_unbound_cpumask, housekeeping_cpumask(HK_FLAG_DOMAIN));
 
 	pwq_cache = KMEM_CACHE(pool_workqueue, SLAB_PANIC);
 
-- 
2.25.1