| Message ID | 20170609105451.461-1-jlee@suse.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Fri, Jun 9, 2017 at 1:54 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. Below looks better for my taste. See also comments. > +static int acpi_ost_status_code(u32 src, int error) > +{ > + switch (src) { > + case ACPI_NOTIFY_EJECT_REQUEST: > + case ACPI_OST_EC_OSPM_EJECT: > + if (error == -EPERM) > + return ACPI_OST_SC_EJECT_NOT_SUPPORTED; > + else if (error == -EBUSY) Redundant else... > + return ACPI_OST_SC_DEVICE_BUSY; Perhaps switch case here as well? switch (error) { case -EPERM; return X; case -EBUSY: return Y; } > + break; > + } > + return error ? ACPI_OST_SC_NON_SPECIFIC_FAILURE : ACPI_OST_SC_SUCCESS; > +} > + ost_code = acpi_ost_status_code(src, error); > err_out: I guess you need to swap those lines. > acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
On Fri, Jun 09, 2017 at 06:36:32PM +0300, Andy Shevchenko wrote: > On Fri, Jun 9, 2017 at 1:54 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. > > Below looks better for my taste. > See also comments. > Still thanks for your review. > > +static int acpi_ost_status_code(u32 src, int error) > > +{ > > + switch (src) { > > + case ACPI_NOTIFY_EJECT_REQUEST: > > + case ACPI_OST_EC_OSPM_EJECT: > > > + if (error == -EPERM) > > + return ACPI_OST_SC_EJECT_NOT_SUPPORTED; > > + else if (error == -EBUSY) > > Redundant else... > You are right, I will remove it. > > + return ACPI_OST_SC_DEVICE_BUSY; > > Perhaps switch case here as well? > switch (error) { > case -EPERM; > return X; > case -EBUSY: > return Y; > } > I want to use the event source as the target of switch because different event source has different ost_src definition. If I add the support of insertion event then the code will be like this: static int acpi_ost_status_code(u32 src, int error) { switch (src) { case ACPI_NOTIFY_EJECT_REQUEST: case ACPI_OST_EC_OSPM_EJECT: if (error == -EPERM) return ACPI_OST_SC_EJECT_NOT_SUPPORTED; if (error == -EBUSY) return ACPI_OST_SC_DEVICE_BUSY; break; case ACPI_OST_EC_OSPM_INSERTION: if (error == -EPERM) return ACPI_OST_SC_INSERT_NOT_SUPPORTED; if (error == -EBUSY) return ACPI_OST_SC_INSERT_IN_PROGRESS; break; } return error ? ACPI_OST_SC_NON_SPECIFIC_FAILURE : ACPI_OST_SC_SUCCESS; } The ACPI_OST_EC_OSPM_INSERTION represents "Insertion Processing (Source Event: 0x200)" that it has different ost code definition. Just we didn't support it in kernel (maybe just didn't see any machine used it). > > + break; > > + } > > + return error ? ACPI_OST_SC_NON_SPECIFIC_FAILURE : ACPI_OST_SC_SUCCESS; > > +} > > > > + ost_code = acpi_ost_status_code(src, error); > > err_out: > > I guess you need to swap those lines. > Do you mean move the "err_out:" to the position before acpi_ost_status_code()? The err_out tag used by the validation checking of acpi handler that it wants to jump to evaluate _OST: void acpi_device_hotplug(struct acpi_device *adev, u32 src) { u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; int error = -ENODEV; lock_device_hotplug(); mutex_lock(&acpi_scan_lock); /* * The device object's ACPI handle cannot become invalid as long as we * are holding acpi_scan_lock, but it might have become invalid before * that lock was acquired. */ if (adev->handle == INVALID_ACPI_HANDLE) goto err_out; [...snip] > > err_out: > > acpi_evaluate_ost(adev->handle, src, ost_code, NULL); > Thanks a lot! Joey Lee -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 2433569..e407eed 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -394,6 +394,20 @@ static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type) return -EINVAL; } +static int acpi_ost_status_code(u32 src, int error) +{ + switch (src) { + case ACPI_NOTIFY_EJECT_REQUEST: + case ACPI_OST_EC_OSPM_EJECT: + if (error == -EPERM) + return ACPI_OST_SC_EJECT_NOT_SUPPORTED; + else if (error == -EBUSY) + return ACPI_OST_SC_DEVICE_BUSY; + break; + } + return error ? ACPI_OST_SC_NON_SPECIFIC_FAILURE : ACPI_OST_SC_SUCCESS; +} + void acpi_device_hotplug(struct acpi_device *adev, u32 src) { u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; @@ -414,10 +428,6 @@ 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); @@ -433,9 +443,8 @@ void acpi_device_hotplug(struct acpi_device *adev, u32 src) else goto out; } - if (!error) - ost_code = ACPI_OST_SC_SUCCESS; + ost_code = acpi_ost_status_code(src, error); 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. v2: Do not overwrite ost code in acpi_generic_hotplug_event(). Move the "error code to ost code" logic to a help function. Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com> --- drivers/acpi/scan.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-)