| Message ID | 20170703132610.21719-1-jlee@suse.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
On Mon, Jul 3, 2017 at 4:26 PM, Lee, Chun-Yi <joeyli.kernel@gmail.com> wrote: > In hotplug logic, it always indicates non-specific failure to > platform through _OST when handing acpi hot-remove event failed. Then > platform terminates the hot-remove process but it can not identify > the reason. > > Base on current hot-remove code, there have two situations that it > returns busy: > - OSPM try to offline an individual device, but the device offline > function returns busy. > - When the ejection event is applied to an "not offlined yet" container. > OSPM send kobject change event to userspace and returns busy. > > Both of them will returns -EBUSY to acpi device hotplug function then > hotplug function indicates non-specific failure to platform just like > any other error, e.g. -ENODEV or -EIO. > > The benefit to platform for identifying the OS busy state is that > platform can be applied different approach to handle the busy but > not just terminate the hot-remove process by unknown reason. For > example, platform can wait for a while then triggers hot-remove > again. > > This RFC patch adds one more parameter to the handler function of > acpi generic hotplug event to give the function a chance to propose > the return code of _OST. In this case, it sets ost return code to > ACPI_OST_SC_DEVICE_BUSY when the acpi hot remove function returns > -EBUSY. > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > v4: > Use switch-case statements to simplify code. (Andy Shevchenko, Rafael J. Wysocki) > > v3: > Removed redundant 'else' in acpi_ost_status_code(). (Andy Shevchenko) > > v2: > Do not overwrite ost code in acpi_generic_hotplug_event(). Move > the "error code to ost code" logic to a help function. (Andy Shevchenko) > > Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > Cc: Len Brown <lenb@kernel.org> > Cc: Andy Shevchenko <andy.shevchenko@gmail.com> > Cc: Michal Hocko <mhocko@suse.cz> > Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com> > --- > drivers/acpi/scan.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index d531629..ce88175 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -404,10 +404,6 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src) > error = dock_notify(adev, src); > } else if (adev->flags.hotplug_notify) { > error = acpi_generic_hotplug_event(adev, src); > - if (error == -EPERM) { > - ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; > - goto err_out; > - } > } else { > int (*notify)(struct acpi_device *, u32); > > @@ -423,8 +419,20 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src) > else > goto out; > } > - if (!error) > + switch (error) { > + case 0: > ost_code = ACPI_OST_SC_SUCCESS; > + break; > + case -EPERM: > + ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; > + break; > + case -EBUSY: > + ost_code = ACPI_OST_SC_DEVICE_BUSY; > + break; > + default: > + ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; > + break; > + } > > err_out: > acpi_evaluate_ost(adev->handle, src, ost_code, NULL); > -- > 2.10.2 >
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index d531629..ce88175 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -404,10 +404,6 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src) error = dock_notify(adev, src); } else if (adev->flags.hotplug_notify) { error = acpi_generic_hotplug_event(adev, src); - if (error == -EPERM) { - ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; - goto err_out; - } } else { int (*notify)(struct acpi_device *, u32); @@ -423,8 +419,20 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src) else goto out; } - if (!error) + switch (error) { + case 0: ost_code = ACPI_OST_SC_SUCCESS; + break; + case -EPERM: + ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; + break; + case -EBUSY: + ost_code = ACPI_OST_SC_DEVICE_BUSY; + break; + default: + ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; + break; + } err_out: acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
In hotplug logic, it always indicates non-specific failure to platform through _OST when handing acpi hot-remove event failed. Then platform terminates the hot-remove process but it can not identify the reason. Base on current hot-remove code, there have two situations that it returns busy: - OSPM try to offline an individual device, but the device offline function returns busy. - When the ejection event is applied to an "not offlined yet" container. OSPM send kobject change event to userspace and returns busy. Both of them will returns -EBUSY to acpi device hotplug function then hotplug function indicates non-specific failure to platform just like any other error, e.g. -ENODEV or -EIO. The benefit to platform for identifying the OS busy state is that platform can be applied different approach to handle the busy but not just terminate the hot-remove process by unknown reason. For example, platform can wait for a while then triggers hot-remove again. This RFC patch adds one more parameter to the handler function of acpi generic hotplug event to give the function a chance to propose the return code of _OST. In this case, it sets ost return code to ACPI_OST_SC_DEVICE_BUSY when the acpi hot remove function returns -EBUSY. v4: Use switch-case statements to simplify code. (Andy Shevchenko, Rafael J. Wysocki) v3: Removed redundant 'else' in acpi_ost_status_code(). (Andy Shevchenko) v2: Do not overwrite ost code in acpi_generic_hotplug_event(). Move the "error code to ost code" logic to a help function. (Andy Shevchenko) Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com> --- drivers/acpi/scan.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)