| Message ID | 1488288869-31290-3-git-send-email-rui.y.wang@intel.com |
|---|---|
| State | Not Applicable |
| Headers | show |
On Tue, Feb 28, 2017 at 09:34:29PM +0800, Rui Wang wrote: > The hot-removal of IOAPIC is broken into two parts: the PCI part and > the ACPI part. The PCI part releases PCI resources before the PCI bus > is gone, and the ACPI part is moved to a stage later than the hot-removal > of the PCI root bus, so that the IOAPIC driver is able to hook the > pcibios_release_device() of every PCI device under the same parent root > bus, before the IOAPIC is hot-removed. This makes it possible for the > IOAPIC to free any IRQ resource previously unable to get freed. > > v2: Fixed compiling error on i386 (missing stub of pci_ioapic_remove()) > > Signed-off-by: Rui Wang <rui.y.wang@intel.com> Minor comments below, but Acked-by: Bjorn Helgaas <bhelgaas@google.com> > --- > drivers/acpi/internal.h | 2 ++ > drivers/acpi/ioapic.c | 22 ++++++++++++++++------ > drivers/acpi/pci_root.c | 4 ++-- > 3 files changed, 20 insertions(+), 8 deletions(-) > > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 219b90b..f159001 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -41,8 +41,10 @@ static inline void acpi_amba_init(void) {} > void acpi_container_init(void); > void acpi_memory_hotplug_init(void); > #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC > +void pci_ioapic_remove(struct acpi_pci_root *root); > int acpi_ioapic_remove(struct acpi_pci_root *root); > #else > +static inline void pci_ioapic_remove(struct acpi_pci_root *root) { return; } Superfluous "return;" here. > static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0; } > #endif > #ifdef CONFIG_ACPI_DOCK > diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c > index 6d7ce6e..1120dfd6 100644 > --- a/drivers/acpi/ioapic.c > +++ b/drivers/acpi/ioapic.c > @@ -206,24 +206,34 @@ int acpi_ioapic_add(acpi_handle root_handle) > return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV; > } > > -int acpi_ioapic_remove(struct acpi_pci_root *root) > +void pci_ioapic_remove(struct acpi_pci_root *root) > { > - int retval = 0; > struct acpi_pci_ioapic *ioapic, *tmp; > > mutex_lock(&ioapic_list_lock); > list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) { I don't think it's necessary to use the "safe" iterator here, since you're not modifying ioapic_list in the loop any more. > if (root->device->handle != ioapic->root_handle) > continue; > - > - if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base)) > - retval = -EBUSY; > - > if (ioapic->pdev) { > pci_release_region(ioapic->pdev, 0); > pci_disable_device(ioapic->pdev); > pci_dev_put(ioapic->pdev); > } > + } > + mutex_unlock(&ioapic_list_lock); > +} > + > +int acpi_ioapic_remove(struct acpi_pci_root *root) > +{ > + int retval = 0; > + struct acpi_pci_ioapic *ioapic, *tmp; > + > + mutex_lock(&ioapic_list_lock); > + list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) { > + if (root->device->handle != ioapic->root_handle) > + continue; > + if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base)) > + retval = -EBUSY; > if (ioapic->res.flags && ioapic->res.parent) > release_resource(&ioapic->res); > list_del(&ioapic->list); > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > index bf601d4..919be0a 100644 > --- a/drivers/acpi/pci_root.c > +++ b/drivers/acpi/pci_root.c > @@ -648,12 +648,12 @@ static void acpi_pci_root_remove(struct acpi_device *device) > > pci_stop_root_bus(root->bus); > > - WARN_ON(acpi_ioapic_remove(root)); > - > + pci_ioapic_remove(root); > device_set_run_wake(root->bus->bridge, false); > pci_acpi_remove_bus_pm_notifier(device); > > pci_remove_root_bus(root->bus); > + WARN_ON(acpi_ioapic_remove(root)); You didn't change this, but my personal preference is not to call functions with side-effects inside a WARN_ON() or BUG_ON(). The acpi_ioapic_remove() call is essential here, and I think it gets obscured a bit by being inside WARN_ON(). > dmar_device_remove(device->handle); > > -- > 1.8.3.1 >
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 219b90b..f159001 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -41,8 +41,10 @@ static inline void acpi_amba_init(void) {} void acpi_container_init(void); void acpi_memory_hotplug_init(void); #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC +void pci_ioapic_remove(struct acpi_pci_root *root); int acpi_ioapic_remove(struct acpi_pci_root *root); #else +static inline void pci_ioapic_remove(struct acpi_pci_root *root) { return; } static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0; } #endif #ifdef CONFIG_ACPI_DOCK diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c index 6d7ce6e..1120dfd6 100644 --- a/drivers/acpi/ioapic.c +++ b/drivers/acpi/ioapic.c @@ -206,24 +206,34 @@ int acpi_ioapic_add(acpi_handle root_handle) return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV; } -int acpi_ioapic_remove(struct acpi_pci_root *root) +void pci_ioapic_remove(struct acpi_pci_root *root) { - int retval = 0; struct acpi_pci_ioapic *ioapic, *tmp; mutex_lock(&ioapic_list_lock); list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) { if (root->device->handle != ioapic->root_handle) continue; - - if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base)) - retval = -EBUSY; - if (ioapic->pdev) { pci_release_region(ioapic->pdev, 0); pci_disable_device(ioapic->pdev); pci_dev_put(ioapic->pdev); } + } + mutex_unlock(&ioapic_list_lock); +} + +int acpi_ioapic_remove(struct acpi_pci_root *root) +{ + int retval = 0; + struct acpi_pci_ioapic *ioapic, *tmp; + + mutex_lock(&ioapic_list_lock); + list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) { + if (root->device->handle != ioapic->root_handle) + continue; + if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base)) + retval = -EBUSY; if (ioapic->res.flags && ioapic->res.parent) release_resource(&ioapic->res); list_del(&ioapic->list); diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index bf601d4..919be0a 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -648,12 +648,12 @@ static void acpi_pci_root_remove(struct acpi_device *device) pci_stop_root_bus(root->bus); - WARN_ON(acpi_ioapic_remove(root)); - + pci_ioapic_remove(root); device_set_run_wake(root->bus->bridge, false); pci_acpi_remove_bus_pm_notifier(device); pci_remove_root_bus(root->bus); + WARN_ON(acpi_ioapic_remove(root)); dmar_device_remove(device->handle);
The hot-removal of IOAPIC is broken into two parts: the PCI part and the ACPI part. The PCI part releases PCI resources before the PCI bus is gone, and the ACPI part is moved to a stage later than the hot-removal of the PCI root bus, so that the IOAPIC driver is able to hook the pcibios_release_device() of every PCI device under the same parent root bus, before the IOAPIC is hot-removed. This makes it possible for the IOAPIC to free any IRQ resource previously unable to get freed. v2: Fixed compiling error on i386 (missing stub of pci_ioapic_remove()) Signed-off-by: Rui Wang <rui.y.wang@intel.com> --- drivers/acpi/internal.h | 2 ++ drivers/acpi/ioapic.c | 22 ++++++++++++++++------ drivers/acpi/pci_root.c | 4 ++-- 3 files changed, 20 insertions(+), 8 deletions(-)