[tip: sched/core] workqueue: Decouple HK_FLAG_WQ and HK_FLAG_DOMAIN cpumask fetch

From: tip-bot2 for Frederic Weisbecker
Date: Thu Feb 17 2022 - 13:57:18 EST


The following commit has been merged into the sched/core branch of tip:

Commit-ID: 7b45b51e778021cd7817b8f0d743a2c73205c011
Gitweb: https://git.kernel.org/tip/7b45b51e778021cd7817b8f0d743a2c73205c011
Author: Frederic Weisbecker <frederic@xxxxxxxxxx>
AuthorDate: Mon, 07 Feb 2022 16:59:04 +01:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Wed, 16 Feb 2022 15:57:54 +01:00

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: Frederic Weisbecker <frederic@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Juri Lelli <juri.lelli@xxxxxxxxxx>
Reviewed-by: Phil Auld <pauld@xxxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220207155910.527133-3-frederic@xxxxxxxxxx
---
kernel/workqueue.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 33f1106..61ed310 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);