* [PATCH 1/3] ACPI,PCI: Use normal list for struct acpi_pci_driver
2012-03-21 16:22 [PATCH 0/3] Enhance pci_root.c to better support PCI root bus hotplug Jiang Liu
@ 2012-03-21 16:22 ` Jiang Liu
2012-03-21 16:22 ` [PATCH 2/3] ACPI,PCI: Notify acpi_pci_drivers when hot-plugging PCI root bridges Jiang Liu
2012-03-21 16:22 ` [PATCH 3/3] ACPI,PCI: protect global lists in drivers/acpi/pci_root.c Jiang Liu
2 siblings, 0 replies; 7+ messages in thread
From: Jiang Liu @ 2012-03-21 16:22 UTC (permalink / raw)
To: Yinghai Lu, Len Brown
Cc: Liu Jiang, Jesse Barnes, Bjorn Helgaas, Ashok Raj, linux-pci,
linux-acpi, chenkeping
From: Liu Jiang <jiang.liu@huawei.com>
Use normal list for struct acpi_pci_driver to simplify code.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
---
drivers/acpi/pci_root.c | 16 +++-------------
include/linux/acpi.h | 2 +-
2 files changed, 4 insertions(+), 14 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index b38e347..c2d2b7b 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -72,8 +72,8 @@ static struct acpi_driver acpi_pci_root_driver = {
};
static LIST_HEAD(acpi_pci_roots);
+static LIST_HEAD(acpi_pci_drivers);
-static struct acpi_pci_driver *sub_driver;
static DEFINE_MUTEX(osc_lock);
int acpi_pci_register_driver(struct acpi_pci_driver *driver)
@@ -81,10 +81,7 @@ int acpi_pci_register_driver(struct acpi_pci_driver *driver)
int n = 0;
struct acpi_pci_root *root;
- struct acpi_pci_driver **pptr = &sub_driver;
- while (*pptr)
- pptr = &(*pptr)->next;
- *pptr = driver;
+ list_add_tail(&driver->node, &acpi_pci_drivers);
if (!driver->add)
return 0;
@@ -103,14 +100,7 @@ void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
{
struct acpi_pci_root *root;
- struct acpi_pci_driver **pptr = &sub_driver;
- while (*pptr) {
- if (*pptr == driver)
- break;
- pptr = &(*pptr)->next;
- }
- BUG_ON(!*pptr);
- *pptr = (*pptr)->next;
+ list_del(&driver->node);
if (!driver->remove)
return;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 3f96866..efcc6c4 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -138,7 +138,7 @@ void acpi_penalize_isa_irq(int irq, int active);
void acpi_pci_irq_disable (struct pci_dev *dev);
struct acpi_pci_driver {
- struct acpi_pci_driver *next;
+ struct list_head node;
int (*add)(acpi_handle handle);
void (*remove)(acpi_handle handle);
};
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/3] ACPI,PCI: Notify acpi_pci_drivers when hot-plugging PCI root bridges
2012-03-21 16:22 [PATCH 0/3] Enhance pci_root.c to better support PCI root bus hotplug Jiang Liu
2012-03-21 16:22 ` [PATCH 1/3] ACPI,PCI: Use normal list for struct acpi_pci_driver Jiang Liu
@ 2012-03-21 16:22 ` Jiang Liu
2012-03-21 17:04 ` Yinghai Lu
2012-03-21 16:22 ` [PATCH 3/3] ACPI,PCI: protect global lists in drivers/acpi/pci_root.c Jiang Liu
2 siblings, 1 reply; 7+ messages in thread
From: Jiang Liu @ 2012-03-21 16:22 UTC (permalink / raw)
To: Yinghai Lu, Len Brown
Cc: Jiang Liu, Jesse Barnes, Bjorn Helgaas, Ashok Raj, linux-pci,
linux-acpi, chenkeping, Jiang Liu
From: Jiang Liu <liuj97@gmail.com>
When hot-plugging PCI root bridge, acpi_pci_drivers' add()/remove()
methods should be invoked to notify registered drivers.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
---
drivers/acpi/pci_root.c | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index c2d2b7b..ff73357 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -445,6 +445,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
acpi_status status;
int result;
struct acpi_pci_root *root;
+ struct acpi_pci_driver *driver;
acpi_handle handle;
struct acpi_device *child;
u32 flags, base_flags;
@@ -612,6 +613,10 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
if (device->wakeup.flags.run_wake)
device_set_run_wake(root->bus->bridge, true);
+ list_for_each_entry(driver, &acpi_pci_drivers, node)
+ if (driver->add)
+ driver->add(device->handle);
+
return 0;
end:
@@ -632,6 +637,11 @@ static int acpi_pci_root_start(struct acpi_device *device)
static int acpi_pci_root_remove(struct acpi_device *device, int type)
{
struct acpi_pci_root *root = acpi_driver_data(device);
+ struct acpi_pci_driver *driver;
+
+ list_for_each_entry(driver, &acpi_pci_drivers, node)
+ if (driver->remove)
+ driver->remove(root->device->handle);
/* that root bus could be removed already */
if (!pci_find_bus(root->segment, root->secondary.start)) {
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 3/3] ACPI,PCI: protect global lists in drivers/acpi/pci_root.c
2012-03-21 16:22 [PATCH 0/3] Enhance pci_root.c to better support PCI root bus hotplug Jiang Liu
2012-03-21 16:22 ` [PATCH 1/3] ACPI,PCI: Use normal list for struct acpi_pci_driver Jiang Liu
2012-03-21 16:22 ` [PATCH 2/3] ACPI,PCI: Notify acpi_pci_drivers when hot-plugging PCI root bridges Jiang Liu
@ 2012-03-21 16:22 ` Jiang Liu
2 siblings, 0 replies; 7+ messages in thread
From: Jiang Liu @ 2012-03-21 16:22 UTC (permalink / raw)
To: Yinghai Lu, Len Brown
Cc: Jiang Liu, Jesse Barnes, Bjorn Helgaas, Ashok Raj, linux-pci,
linux-acpi, chenkeping, Jiang Liu
From: Jiang Liu <liuj97@gmail.com>
There are two global lists inf file drivers/acpi/pci_root.c.
One is for registered acpi_pci_drivers, the other is for
enumerated ACPI PCI root bridge objects. These two global
lists may change dynamically when registering/deregistering
acpi_pci_drivers or adding/removing ACPI PCI root bridge
objects. So protect them by mutex lock and RCU list.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
---
drivers/acpi/pci_root.c | 85 ++++++++++++++++++++++++++++-------------------
1 files changed, 51 insertions(+), 34 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index ff73357..24afd66 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -27,7 +27,8 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
-#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/rculist.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/pci.h>
@@ -71,6 +72,8 @@ static struct acpi_driver acpi_pci_root_driver = {
},
};
+/* Lock to protect both acpi_pci_roots and acpi_pci_drivers lists */
+static DEFINE_MUTEX(acpi_pci_root_lock);
static LIST_HEAD(acpi_pci_roots);
static LIST_HEAD(acpi_pci_drivers);
@@ -81,47 +84,48 @@ int acpi_pci_register_driver(struct acpi_pci_driver *driver)
int n = 0;
struct acpi_pci_root *root;
+ mutex_lock(&acpi_pci_root_lock);
list_add_tail(&driver->node, &acpi_pci_drivers);
-
- if (!driver->add)
- return 0;
-
- list_for_each_entry(root, &acpi_pci_roots, node) {
- driver->add(root->device->handle);
- n++;
- }
+ if (driver->add)
+ list_for_each_entry_rcu(root, &acpi_pci_roots, node) {
+ driver->add(root->device->handle);
+ n++;
+ }
+ mutex_unlock(&acpi_pci_root_lock);
return n;
}
-
EXPORT_SYMBOL(acpi_pci_register_driver);
void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
{
struct acpi_pci_root *root;
+ mutex_lock(&acpi_pci_root_lock);
list_del(&driver->node);
-
- if (!driver->remove)
- return;
-
- list_for_each_entry(root, &acpi_pci_roots, node)
- driver->remove(root->device->handle);
+ if (driver->remove)
+ list_for_each_entry_rcu(root, &acpi_pci_roots, node)
+ driver->remove(root->device->handle);
+ mutex_unlock(&acpi_pci_root_lock);
}
-
EXPORT_SYMBOL(acpi_pci_unregister_driver);
acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
{
struct acpi_pci_root *root;
+ struct acpi_handle *handle = NULL;
- list_for_each_entry(root, &acpi_pci_roots, node)
+ rcu_read_lock();
+ list_for_each_entry_rcu(root, &acpi_pci_roots, node)
if ((root->segment == (u16) seg) &&
- (root->secondary.start == (u16) bus))
- return root->device->handle;
- return NULL;
-}
+ (root->secondary.start == (u16) bus)) {
+ handle = root->device->handle;
+ break;
+ }
+ rcu_read_unlock();
+ return handle;
+}
EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
/**
@@ -268,10 +272,15 @@ struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
{
struct acpi_pci_root *root;
- list_for_each_entry(root, &acpi_pci_roots, node) {
- if (root->device->handle == handle)
+ rcu_read_lock();
+ list_for_each_entry_rcu(root, &acpi_pci_roots, node) {
+ if (root->device->handle == handle) {
+ rcu_read_unlock();
return root;
+ }
}
+ rcu_read_unlock();
+
return NULL;
}
EXPORT_SYMBOL_GPL(acpi_pci_find_root);
@@ -460,7 +469,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
result = -ENODEV;
- goto end;
+ goto out_free;
}
/* Check _CRS first, then _BBN. If no _BBN, default to zero. */
@@ -485,7 +494,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
else {
printk(KERN_ERR PREFIX "can't evaluate _BBN\n");
result = -ENODEV;
- goto end;
+ goto out_free;
}
}
@@ -507,8 +516,8 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
* TBD: Need PCI interface for enumeration/configuration of roots.
*/
- /* TBD: Locking */
- list_add_tail(&root->node, &acpi_pci_roots);
+ mutex_lock(&acpi_pci_root_lock);
+ list_add_tail_rcu(&root->node, &acpi_pci_roots);
printk(KERN_INFO PREFIX "%s [%s] (domain %04x %pR)\n",
acpi_device_name(device), acpi_device_bid(device),
@@ -527,7 +536,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
"Bus %04x:%02x not present in PCI namespace\n",
root->segment, (unsigned int)root->secondary.start);
result = -ENODEV;
- goto end;
+ goto out_del_root;
}
/*
@@ -537,7 +546,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
*/
result = acpi_pci_bind_root(device);
if (result)
- goto end;
+ goto out_del_root;
/*
* PCI Routing Table
@@ -617,11 +626,15 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
if (driver->add)
driver->add(device->handle);
+ mutex_unlock(&acpi_pci_root_lock);
+
return 0;
-end:
- if (!list_empty(&root->node))
- list_del(&root->node);
+out_del_root:
+ list_del_rcu(&root->node);
+ mutex_unlock(&acpi_pci_root_lock);
+ synchronize_rcu();
+out_free:
kfree(root);
return result;
}
@@ -639,6 +652,8 @@ static int acpi_pci_root_remove(struct acpi_device *device, int type)
struct acpi_pci_root *root = acpi_driver_data(device);
struct acpi_pci_driver *driver;
+ mutex_lock(&acpi_pci_root_lock);
+
list_for_each_entry(driver, &acpi_pci_drivers, node)
if (driver->remove)
driver->remove(root->device->handle);
@@ -658,7 +673,9 @@ static int acpi_pci_root_remove(struct acpi_device *device, int type)
pci_stop_and_remove_bus(root->bus);
out:
- list_del(&root->node);
+ list_del_rcu(&root->node);
+ mutex_unlock(&acpi_pci_root_lock);
+ synchronize_rcu();
kfree(root);
return 0;
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread