From ad5086108b9f0361929aa9a79cf959ab5681d249 Mon Sep 17 00:00:00 2001 From: Yunsheng Lin Date: Sat, 19 Oct 2019 14:45:43 +0800 Subject: [PATCH] PCI: Warn if no host bridge NUMA node info In pci_call_probe(), we try to run driver probe functions on the node where the device is attached. If we don't know which node the device is attached to, the driver will likely run on the wrong node. This will still work, but performance will not be as good as it could be. On NUMA systems, warn if we don't know which node a PCI host bridge is attached to. This is likely an indication that ACPI didn't supply a _PXM method or the DT didn't supply a "numa-node-id" property. [bhelgaas: commit log, check bus node] Link: https://lore.kernel.org/r/1571467543-26125-1-git-send-email-linyunsheng@huawei.com Signed-off-by: Yunsheng Lin Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 3d5271a7a849..40259c38d66a 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -897,6 +897,9 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) else pr_info("PCI host bridge to bus %s\n", name); + if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE) + dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n"); + /* Add initial resources to the bus */ resource_list_for_each_entry_safe(window, n, &resources) { list_move_tail(&window->node, &bridge->windows);