Commit 7b45b51e authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Peter Zijlstra
Browse files

workqueue: Decouple HK_FLAG_WQ and HK_FLAG_DOMAIN cpumask fetch 



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.

Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarJuri Lelli <juri.lelli@redhat.com>
Reviewed-by: default avatarPhil Auld <pauld@redhat.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220207155910.527133-3-frederic@kernel.org
parent 9d42ea0d

kernel/workqueue.c

+2 −2
Original line number Diff line number Diff line
@@ -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);