On 2012-9-12 7:21, Bjorn Helgaas wrote:

On Tue, Aug 7, 2012 at 10:11 AM, Jiang Liu [off-list ref] wrote:

quoted

Now all Archs have been converted to the new PCI bus lock mechanism,
so clean up unused code.

When you say "all arches," do you really mean "x86 and ia64"?  I
assume all the other architectures have similar issues.  Or is this
somehow ACPI-specific?

Hi Bjorn,
	It's still RFC to give an overview of the whole patch set. 
Here I mean once we have enhanced all arches, we will apply following patches:)
I'm working to enhance all arches recently, and will post the latest patch
once it passes basic tests.
	Thanks!

quoted

Signed-off-by: Jiang Liu <redacted>
---
 drivers/pci/Kconfig     |    3 ---
 drivers/pci/bus.c       |    1 -
 drivers/pci/pci-sysfs.c |    9 ---------
 drivers/pci/probe.c     |    4 +---
 include/linux/pci.h     |   10 ----------
 5 files changed, 1 insertion(+), 26 deletions(-)

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 5a796c0..848bfb8 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig

@@ -120,6 +120,3 @@ config PCI_IOAPIC
 config PCI_LABEL
        def_bool y if (DMI || ACPI)
        select NLS
-
-config PCI_BUS_LOCK
-       def_bool y if (X86 || IA64)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 371f20a..308c376 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c

@@ -196,7 +196,6 @@ int pci_bus_add_child(struct pci_bus *bus)
                        pci_create_legacy_files(bus);
                        pci_bus_change_state(bus, PCI_BUS_STATE_INITIALIZED,
                                        PCI_BUS_STATE_WORKING, false);
-                       bus->is_added = 1;
                }
        }

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 11043b4..a5a4195 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c

@@ -284,7 +284,6 @@ msi_bus_store(struct device *dev, struct device_attribute *attr,
 }

 #ifdef CONFIG_HOTPLUG
-static DEFINE_MUTEX(pci_remove_rescan_mutex);
 static ssize_t bus_rescan_store(struct bus_type *bus, const char *buf,
                                size_t count)
 {

@@ -296,13 +295,11 @@ static ssize_t bus_rescan_store(struct bus_type *bus, const char *buf,

        if (val) {
                pci_host_bridge_hotplug_lock();
-               mutex_lock(&pci_remove_rescan_mutex);
                while ((b = pci_find_next_bus(b)) != NULL)
                        if (pci_bus_lock_states(b, PCI_BUS_STATE_WORKING) > 0) {
                                pci_rescan_bus(b);
                                pci_bus_unlock(b);
                        }
-               mutex_unlock(&pci_remove_rescan_mutex);
                pci_host_bridge_hotplug_unlock();
        }
        return count;

@@ -326,13 +323,11 @@ dev_rescan_store(struct device *dev, struct device_attribute *attr,
        if (val) {
                struct pci_bus *bus = pdev->bus;

-               mutex_lock(&pci_remove_rescan_mutex);
                if (pci_bus_lock_states(bus, PCI_BUS_STATE_WORKING) > 0) {
                        if (pdev->is_added)
                                pci_rescan_bus(bus);
                        pci_bus_unlock(bus);
                }
-               mutex_unlock(&pci_remove_rescan_mutex);
        }
        return count;
 }

@@ -342,13 +337,11 @@ static void remove_callback(struct device *dev)
        struct pci_dev *pdev = to_pci_dev(dev);
        struct pci_bus *bus = pdev->bus;

-       mutex_lock(&pci_remove_rescan_mutex);
        if (pci_bus_lock_states(bus, PCI_BUS_STATE_WORKING) > 0) {
                pci_bus_get(bus);
                pci_stop_and_remove_bus_device(pdev);
                pci_unlock_and_put_bus(bus);
        }
-       mutex_unlock(&pci_remove_rescan_mutex);
 }

 static ssize_t

@@ -382,14 +375,12 @@ dev_bus_rescan_store(struct device *dev, struct device_attribute *attr,
                return -EINVAL;

        if (val) {
-               mutex_lock(&pci_remove_rescan_mutex);
                if (!pci_is_root_bus(bus))
                        pci_rescan_bus_bridge_resize(bus->self);
                else if (pci_bus_lock_states(bus, PCI_BUS_STATE_WORKING) > 0) {
                        pci_rescan_bus(bus);
                        pci_bus_unlock(bus);
                }
-               mutex_unlock(&pci_remove_rescan_mutex);
        }
        return count;
 }

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index da6f04c..09517c3 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c

@@ -1626,11 +1626,9 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
        if (pci_bus_get_state(bus) < PCI_BUS_STATE_WORKING) {
                dev_dbg(&bus->dev, "fixups for bus\n");
                pcibios_fixup_bus(bus);
-               if (pci_is_root_bus(bus)) {
+               if (pci_is_root_bus(bus))
                        pci_bus_change_state(bus, PCI_BUS_STATE_REGISTERED,
                                             PCI_BUS_STATE_WORKING, false);
-                       bus->is_added = 1;
-               }
        }

        for (pass=0; pass < 2; pass++)

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 9e52e88..0e50ec8 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h

@@ -442,7 +442,6 @@ struct pci_bus {
        struct device           dev;
        struct bin_attribute    *legacy_io; /* legacy I/O for this bus */
        struct bin_attribute    *legacy_mem; /* legacy mem */
-       unsigned int            is_added:1;
        atomic_t                state;
 };

@@ -463,21 +462,12 @@ struct pci_bus {
 #define        PCI_BUS_STATE_DESTROYED         0x40    /* invalid state */
 #define        PCI_BUS_STATE_MASK              0x7F

-#ifdef CONFIG_PCI_BUS_LOCK
 #define        PCI_BUS_STATE_LOCK              0x10000 /* for pci core only */

 static inline bool pci_bus_is_locked(struct pci_bus *bus)
 {
        return !!(atomic_read(&bus->state) & PCI_BUS_STATE_LOCK);
 }
-#else /* CONFIG_PCI_BUS_LOCK */
-#define        PCI_BUS_STATE_LOCK              0x0000  /* for pci core only */
-
-static inline bool pci_bus_is_locked(struct pci_bus *bus)
-{
-       return true;
-}
-#endif /* CONFIG_PCI_BUS_LOCK */

 static inline int pci_bus_get_state(struct pci_bus *bus)
 {
--

1.7.9.5

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