[PATCH 20/33] PCI: Remove superfluous HK_TYPE_WQ check

Frederic Weisbecker
2025-10-13T20:34:33Z

It doesn't make sense to use nohz_full without also isolating the
related CPUs from the domain topology, either through the use of
isolcpus= or cpuset isolated partitions.

And now HK_TYPE_DOMAIN includes all kinds of domain isolated CPUs.

This means that HK_TYPE_KERNEL_NOISE (of which HK_TYPE_WQ is only an
alias) should always be a subset of HK_TYPE_DOMAIN.

Therefore sane configurations verify:

HK_TYPE_KERNEL_NOISE | HK_TYPE_DOMAIN == HK_TYPE_DOMAIN

Simplify the PCI probe target election accordingly.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
---
drivers/pci/pci-driver.c | 17 +++--------------
1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index ac86aaec8bcf..e731aaf28c76 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -384,16 +384,9 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
pci_physfn_is_probed(dev)) {
error = local_pci_probe(&ddi);
} else {
- cpumask_var_t wq_domain_mask;
struct pci_probe_arg arg = { .ddi = &ddi };

INIT_WORK_ONSTACK(&arg.work, local_pci_probe_callback);
-
- if (!zalloc_cpumask_var(&wq_domain_mask, GFP_KERNEL)) {
- error = -ENOMEM;
- goto out;
- }
-
/*
* The target election and the enqueue of the work must be within
* the same RCU read side section so that when the workqueue pool
@@ -402,12 +395,9 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
* targets.
*/
rcu_read_lock();
- cpumask_and(wq_domain_mask,
- housekeeping_cpumask(HK_TYPE_WQ),
- housekeeping_cpumask(HK_TYPE_DOMAIN));
-
cpu = cpumask_any_and(cpumask_of_node(node),
- wq_domain_mask);
+ housekeeping_cpumask(HK_TYPE_DOMAIN));
+
if (cpu < nr_cpu_ids) {
struct workqueue_struct *wq = pci_probe_wq;

@@ -422,10 +412,9 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
error = local_pci_probe(&ddi);
}

- free_cpumask_var(wq_domain_mask);
destroy_work_on_stack(&arg.work);
}
-out:
+
dev->is_probed = 0;
cpu_hotplug_enable();
return error;
--
2.51.0