sched/doc: Update documentation for base_slice_ns and CONFIG_HZ relation

The tunable base_slice_ns is dependent on CONFIG_HZ (i.e. TICK_NSEC)
for any significant performance improvement. The reason being the
scheduler tick is not frequent enough to force preemption when
base_slice expires in case of:

base_slice_ns < TICK_NSEC

The below data is of stress-ng:

Number of CPU: 1
Stressor threads: 4
Time: 30sec

On CONFIG_HZ=1000

| base_slice | avg-run (msec) | context-switches |
| ---------- | -------------- | ---------------- |
| 3ms | 2.914 | 10342 |
| 6ms | 4.857 | 6196 |
| 9ms | 6.754 | 4482 |
| 12ms | 7.872 | 3802 |
| 22ms | 11.294 | 2710 |
| 32ms | 13.425 | 2284 |

On CONFIG_HZ=100

| base_slice | avg-run (msec) | context-switches |
| ---------- | -------------- | ---------------- |
| 3ms | 9.144 | 3337 |
| 6ms | 9.113 | 3301 |
| 9ms | 8.991 | 3315 |
| 12ms | 12.935 | 2328 |
| 22ms | 16.031 | 1915 |
| 32ms | 18.608 | 1622 |

base_slice: the value of base_slice in ms
avg-run (msec): average time of the stressor threads got on cpu before
it got preempted
context-switches: number of context switches for the stress-ng process

Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@linux.ibm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20240320173815.927637-2-mchauras@linux.ibm.com

sched/doc: Update documentation after renames and synchronize Chinese version

Update the documentation after these changes, which didn't entirely
propagate the changes:

e23edc86b09d ("sched/fair: Rename check_preempt_curr() to wakeup_preempt()")
03b7fad167ef ("sched: Add task_struct pointer to sched_class::set_curr_task")
2f88c8e802c8 ("sched/eevdf/doc: Modify the documented knob to base_slice_ns as well")

[ mingo: Reworked the changelog. ]

Signed-off-by: Wenyu Huang <huangwenyu5@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org

sched/eevdf/doc: Modify the documented knob to base_slice_ns as well

After committing the scheduler to EEVDF, we renamed the 'min_granularity_ns'
sysctl to 'base_slice_ns':

e4ec3318a17f ("sched/debug: Rename sysctl_sched_min_granularity to sysctl_sched_base_slice")

... but we forgot to rename it in the documentation. Do that now.

Fixes: e4ec3318a17f ("sched/debug: Rename sysctl_sched_min_granularity to sysctl_sched_base_slice")
Signed-off-by: Shrikanth Hegde <sshegde@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230824080342.543396-1-sshegde@linux.vnet.ibm.com

docs: scheduler: Update new path for the sysctl knobs

Add missing update for the documentation bit of some scheduler knob.
The knobs have been moved to /debug/sched/ location (with adjusted names).

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Alex Shi <alexs@kernel.org>
Tested-by: Yanteng Si <siyanteng@loongson.cn>
Link: https://lore.kernel.org/r/20220816121907.841-1-lukasz.luba@arm.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs/scheduler/sched-design-CFS: formatting fix

Fix the rendering of the paragraph. Before the fix, the first line is
rendered in bold (I'm not quite sure why) and is also separated from the
rest of the paragraph, which is rendered with an indent.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20210120001824.385168-3-kolyshkin@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: cgroup-v1: add it to the admin-guide book

Those files belong to the admin guide, so add them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

docs: scheduler: convert docs to ReST and rename to *.rst

In order to prepare to add them to the Kernel API book,
convert the files to ReST format.

The conversion is actually:
- add blank lines and identation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>