Two categories of sched_ext diagnostics are currently undocumented:
1. Per-scheduler events sysfs file
Each active BPF scheduler exposes a set of diagnostic counters at
/sys/kernel/sched_ext/<name>/events. These counters are defined
(with detailed comments) in kernel/sched/ext_internal.h but have
no corresponding documentation in sched-ext.rst. BPF scheduler
developers must read kernel source to understand what each counter
means.
Add a description of the events file, an example of its output, and
a brief explanation of every counter.
2. Module parameters
kernel/sched/ext.c registers two parameters under the sched_ext.
prefix (slice_bypass_us, bypass_lb_intv_us) via module_param_cb()
with MODULE_PARM_DESC() strings, but sched-ext.rst makes no mention
of them. Users who need to tune bypass-mode behavior have no
in-tree documentation to consult.
Add a "Module Parameters" section documenting both knobs: their
default values, valid ranges (taken from the set_*() validators in
ext.c), and the note from the source that they are primarily for
debugging.
No functional changes.
Signed-off-by: zhidao su <suzhidao@xiaomi.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
7e226f036a