2 files changed, 36 insertions, 0 deletions

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 4d762fc4878c..c27e782e6df9 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -17,6 +17,31 @@ config PCI_MSI
 
            If you don't know what to do here, say N.
 
+config PCI_MULTITHREAD_PROBE
+        bool "PCI Multi-threaded probe (EXPERIMENTAL)"
+        depends on PCI && EXPERIMENTAL
+        help
+          Say Y here if you want the PCI core to spawn a new thread for
+          every PCI device that is probed.  This can cause a huge
+          speedup in boot times on multiprocessor machines, and even a
+          smaller speedup on single processor machines.
+
+          But it can also cause lots of bad things to happen.  A number
+          of PCI drivers can not properly handle running in this way,
+          some will just not work properly at all, while others might
+          decide to blow up power supplies with a huge load all at once,
+          so use this option at your own risk.
+
+          It is very unwise to use this option if you are not using a
+          boot process that can handle devices being created in any
+          order.  A program that can create persistant block and network
+          device names (like udev) is a good idea if you wish to use
+          this option.
+
+          Again, use this option at your own risk, you have been warned!
+
+          When in doubt, say N.
+
 config PCI_DEBUG
         bool "PCI Debugging"
         depends on PCI && DEBUG_KERNEL
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 8948ac9ab681..d8ace1f90dd2 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -17,6 +17,16 @@
  *  Registration of PCI drivers and handling of hot-pluggable devices.
  */
 
+/* multithreaded probe logic */
+static int pci_multithread_probe =
+#ifdef CONFIG_PCI_MULTITHREAD_PROBE
+        1;
+#else
+        0;
+#endif
+__module_param_call("", pci_multithread_probe, param_set_bool, param_get_bool, &pci_multithread_probe, 0644);
+
+
 /*
  * Dynamic device IDs are disabled for !CONFIG_HOTPLUG
  */
@@ -408,6 +418,7 @@ int __pci_register_driver(struct pci_driver *drv, struct module *owner)
         drv->driver.bus = &pci_bus_type;
         drv->driver.owner = owner;
         drv->driver.kobj.ktype = &pci_driver_kobj_type;
+        drv->driver.multithread_probe = pci_multithread_probe;
 
         spin_lock_init(&drv->dynids.lock);
         INIT_LIST_HEAD(&drv->dynids.list);