diff options
| author | James Morse <james.morse@arm.com> | 2024-05-29 14:34:46 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2024-06-28 18:38:33 +0100 |
| commit | 4e1a7df4548003fc081360b0f4edce3f7a991bfc (patch) | |
| tree | cf94859fea1576cf6f9c0e691e680212f1960994 /Documentation/ABI/testing | |
| parent | 828ce929d1c3aff0e9a330fea40d29980e17e256 (diff) | |
cpumask: Add enabled cpumask for present CPUs that can be brought online
The 'offline' file in sysfs shows all offline CPUs, including those
that aren't present. User-space is expected to remove not-present CPUs
from this list to learn which CPUs could be brought online.
CPUs can be present but not-enabled. These CPUs can't be brought online
until the firmware policy changes, which comes with an ACPI notification
that will register the CPUs.
With only the offline and present files, user-space is unable to
determine which CPUs it can try to bring online. Add a new CPU mask
that shows this based on all the registered CPUs.
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
Tested-by: Jianyong Wu <jianyong.wu@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240529133446.28446-20-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'Documentation/ABI/testing')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index e7e160954e79..53ed1a803422 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -694,3 +694,9 @@ Description: (RO) indicates whether or not the kernel directly supports modifying the crash elfcorehdr for CPU hot un/plug and/or on/offline changes. + +What: /sys/devices/system/cpu/enabled +Date: Nov 2022 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + (RO) the list of CPUs that can be brought online. |