fbfddae696
This patch introduces acpi_handle_<level>(), where <level> is a kernel message level such as err/warn/info, to support improved logging messages for ACPI, esp. hot-plug operations. acpi_handle_<level>() appends "ACPI" prefix and ACPI object path to the messages. This improves diagnosis of hotplug operations since an error message in a log file identifies an object that caused an issue. This interface acquires the global namespace mutex to obtain an object path. In interrupt context, it shows the object path as <n/a>. acpi_handle_<level>() takes acpi_handle as an argument, which is passed to ACPI hotplug notify handlers from the ACPICA. Therefore, it is always available unlike other kernel objects, such as device. For example: acpi_handle_err(handle, "Device don't exist, dropping EJECT\n"); logs an error message like this at KERN_ERR. ACPI: \_SB_.SCK4.CPU4: Device don't exist, dropping EJECT ACPI hot-plug drivers can use acpi_handle_<level>() when they need to identify a target ACPI object path in their messages, such as error cases. The usage model is similar to dev_<level>(). acpi_handle_<level>() can be used when a device is not created or is invalid during hot-plug operations. ACPI object path is also consistent on the platform, unlike device name that gets incremented over hotplug operations. ACPI drivers should use dev_<level>() when a device object is valid. Device name provides more user friendly information, and avoids acquiring the global ACPI namespace mutex. ACPI drivers also continue to use pr_<level>() when they do not need to specify device information, such as boot-up messages. Note: ACPI_[WARNING|INFO|ERROR]() are intended for the ACPICA and are not associated with the kernel message level. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Tested-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
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| .. | ||
| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| video | ||
| xen | ||
| Kbuild | ||