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| author | Tejun Heo <tj@kernel.org> | 2026-09-14 22:12:34 -1000 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2026-09-15 06:57:20 -1000 |
| commit | a9e3760b0838299649c0d57cca44daaf40ba3c33 (patch) | |
| tree | 95807ff0e511c05602ef34808cfc660303309057 /Documentation/ABI/testing/sysfs-ibft | |
| download | linux-stable-a9e3760b0838299649c0d57cca44daaf40ba3c33.tar.gz linux-stable-a9e3760b0838299649c0d57cca44daaf40ba3c33.zip | |
sched_ext: Maintain an online cid mask in the scheduler arenagrafted
Schedulers on the default cid mapping treat [0, nr_online_cids) as the
online set and restart on hotplug. Schedulers that install their own mapping
with scx_bpf_cid_override() have no way to learn which cids are online: the
count no longer identifies members and the CPU-form cpumask is unusable from
cid programs. This is an obvious hole in the cid API.
Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's
arena, allocated alongside the per-CPU scratch masks and populated after the
cid mapping is finalized and before ops.init(), for child schedulers too.
The pointer stays valid through ops.exit() with no reference to take. It is
the arena offset as a void pointer, the same form struct_ops arena arguments
arrive in. The verifier types the void return as a scalar for the program's
arena cast.
The mask follows the SCX hotplug notifications: seeded from cpu_active_mask
and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask
only inside a hotplug transition. Updates walk the scheduler list under the
lock that also serializes unlinking. Reads are live, not atomic snapshots.
Root initialization excludes hotplug.
v2: Reworded the getter kerneldoc (Andrea Righi).
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-ibft')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-ibft | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-ibft b/Documentation/ABI/testing/sysfs-ibft new file mode 100644 index 000000000..7d6725fe6 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-ibft @@ -0,0 +1,33 @@ +What: /sys/firmware/ibft/initiator +Date: November 2007 +Contact: Konrad Rzeszutek <ketuzsezr@darnok.org> +Description: The /sys/firmware/ibft/initiator directory will contain + files that expose the iSCSI Boot Firmware Table initiator data. + Usually this contains the Initiator name. + +What: /sys/firmware/ibft/targetX +Date: November 2007 +Contact: Konrad Rzeszutek <ketuzsezr@darnok.org> +Description: The /sys/firmware/ibft/targetX directory will contain + files that expose the iSCSI Boot Firmware Table target data. + Usually this contains the target's IP address, boot LUN, + target name, and what NIC it is associated with. It can also + contain the CHAP name (and password), the reverse CHAP + name (and password) + +What: /sys/firmware/ibft/ethernetX +Date: November 2007 +Contact: Konrad Rzeszutek <ketuzsezr@darnok.org> +Description: The /sys/firmware/ibft/ethernetX directory will contain + files that expose the iSCSI Boot Firmware Table NIC data. + Usually this contains the IP address, MAC, and gateway of the NIC. + +What: /sys/firmware/ibft/acpi_header +Date: March 2016 +Contact: David Bond <dbond@suse.com> +Description: The /sys/firmware/ibft/acpi_header directory will contain files + that expose the SIGNATURE, OEM_ID, and OEM_TABLE_ID fields of the + acpi table header of the iBFT structure. This will allow for + identification of the creator of the table which is useful in + determining quirks associated with some adapters when used in + hardware vs software iscsi initiator mode. |