diff options
author | James Morse <james.morse@arm.com> | 2022-11-02 16:15:24 +0000 |
---|---|---|
committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2024-01-08 12:37:57 +0000 |
commit | 8fc7aed65dda1d73bd1423f9b82029b354ce027d (patch) | |
tree | c265d21faf32a713924f60a84d1b5c5e4e5f63c0 /Documentation | |
parent | 9284d86885edc8e60ac6f27dc5e76c48a017e765 (diff) |
cpumask: Add enabled cpumask for present CPUs that can be brought onlineaarch64/hotplug-vcpu/v6.7
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>
---
Changes since RFCv3 (smaller series);
* Added Documentation/ABI/testing/sysfs-devices-system-cpu entry
Diffstat (limited to 'Documentation')
-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 a1db6db47505..59482c10e0ad 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -693,3 +693,9 @@ 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. |