[tip: sched/urgent] docs: cgroup-v1: Clarify that domain levels are system-specific

[tip-bot2 for Vitalii Bursov]

The following commit has been merged into the sched/urgent branch of tip:

Commit-ID:     0f1c74befa656305ecc85c954dc31f84c1cc26e1
Gitweb:        https://git.kernel.org/tip/0f1c74befa656305ecc85c954dc31f84c1cc26e1
Author:        Vitalii Bursov <vitaly@xxxxxxxxxx>
AuthorDate:    Tue, 30 Apr 2024 18:05:25 +03:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Fri, 17 May 2024 09:48:25 +02:00

docs: cgroup-v1: Clarify that domain levels are system-specific

Add a clarification that domain levels are system-specific
and where to check for system details.

Signed-off-by: Vitalii Bursov <vitaly@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Valentin Schneider <vschneid@xxxxxxxxxx>
Acked-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Link: https://lore.kernel.org/r/42b177a2e897cdf880caf9c2025f5b609e820334.1714488502.git.vitaly@xxxxxxxxxx
---
 Documentation/admin-guide/cgroup-v1/cpusets.rst | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/cgroup-v1/cpusets.rst b/Documentation/admin-guide/cgroup-v1/cpusets.rst
index 7d3415e..f401af5 100644
--- a/Documentation/admin-guide/cgroup-v1/cpusets.rst
+++ b/Documentation/admin-guide/cgroup-v1/cpusets.rst
@@ -568,7 +568,7 @@ on the next tick.  For some applications in special situation, waiting
 
 The 'cpuset.sched_relax_domain_level' file allows you to request changing
 this searching range as you like.  This file takes int value which
-indicates size of searching range in levels ideally as follows,
+indicates size of searching range in levels approximately as follows,
 otherwise initial value -1 that indicates the cpuset has no request.
 
 ====== ===========================================================
@@ -581,6 +581,11 @@ otherwise initial value -1 that indicates the cpuset has no request.
    5   search system wide [on NUMA system]
 ====== ===========================================================
 
+Not all levels can be present and values can change depending on the
+system architecture and kernel configuration. Check
+/sys/kernel/debug/sched/domains/cpu*/domain*/ for system-specific
+details.
+
 The system default is architecture dependent.  The system default
 can be changed using the relax_domain_level= boot parameter.