[PATCH] doc: Fix htmldocs build warnings of stallwarn.rst

From: Zhen Lei
Date: Wed Nov 23 2022 - 04:14:03 EST


Documentation/RCU/stallwarn.rst:
401: WARNING: Literal block expected; none found.
428: WARNING: Literal block expected; none found.
445: WARNING: Literal block expected; none found.
459: WARNING: Literal block expected; none found.
468: WARNING: Literal block expected; none found.

The literal block need to be indented, so add two spaces to each line.

In addition, ':', which is used as a boundary in the literal block, is
replaced by '|'.

Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
Documentation/RCU/stallwarn.rst | 44 ++++++++++++++++-----------------
1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/Documentation/RCU/stallwarn.rst b/Documentation/RCU/stallwarn.rst
index c1e92dfef40d501..0f6a58ebf5d7855 100644
--- a/Documentation/RCU/stallwarn.rst
+++ b/Documentation/RCU/stallwarn.rst
@@ -398,9 +398,9 @@ In kernels built with CONFIG_RCU_CPU_STALL_CPUTIME=y or booted with
rcupdate.rcu_cpu_stall_cputime=1, the following additional information
is supplied with each RCU CPU stall warning::

-rcu: hardirqs softirqs csw/system
-rcu: number: 624 45 0
-rcu: cputime: 69 1 2425 ==> 2500(ms)
+ rcu: hardirqs softirqs csw/system
+ rcu: number: 624 45 0
+ rcu: cputime: 69 1 2425 ==> 2500(ms)

These statistics are collected during the sampling period. The values
in row "number:" are the number of hard interrupts, number of soft
@@ -412,22 +412,22 @@ in milliseconds. Because user-mode tasks normally do not cause RCU CPU
stalls, these tasks are typically kernel tasks, which is why only the
system CPU time are considered.

-The sampling period is shown as follows:
-:<------------first timeout---------->:<-----second timeout----->:
-:<--half timeout-->:<--half timeout-->: :
-: :<--first period-->: :
-: :<-----------second sampling period---------->:
-: : : :
-: snapshot time point 1st-stall 2nd-stall
+The sampling period is shown as follows::

+ |<------------first timeout---------->|<-----second timeout----->|
+ |<--half timeout-->|<--half timeout-->| |
+ | |<--first period-->| |
+ | |<-----------second sampling period---------->|
+ | | | |
+ | snapshot time point 1st-stall 2nd-stall

The following describes four typical scenarios:

1. A CPU looping with interrupts disabled.::

- rcu: hardirqs softirqs csw/system
- rcu: number: 0 0 0
- rcu: cputime: 0 0 0 ==> 2500(ms)
+ rcu: hardirqs softirqs csw/system
+ rcu: number: 0 0 0
+ rcu: cputime: 0 0 0 ==> 2500(ms)

Because interrupts have been disabled throughout the measurement
interval, there are no interrupts and no context switches.
@@ -442,9 +442,9 @@ The following describes four typical scenarios:
and CPU time consumed by hard interrupts, along with non-zero CPU
time consumed by in-kernel execution.::

- rcu: hardirqs softirqs csw/system
- rcu: number: 624 0 0
- rcu: cputime: 49 0 2446 ==> 2500(ms)
+ rcu: hardirqs softirqs csw/system
+ rcu: number: 624 0 0
+ rcu: cputime: 49 0 2446 ==> 2500(ms)

The fact that there are zero softirqs gives a hint that these were
disabled, perhaps via local_bh_disable(). It is of course possible
@@ -456,18 +456,18 @@ The following describes four typical scenarios:

Here, only the number of context switches is zero.::

- rcu: hardirqs softirqs csw/system
- rcu: number: 624 45 0
- rcu: cputime: 69 1 2425 ==> 2500(ms)
+ rcu: hardirqs softirqs csw/system
+ rcu: number: 624 45 0
+ rcu: cputime: 69 1 2425 ==> 2500(ms)

This situation hints that the stalled CPU was looping with preemption
disabled.

4. No looping, but massive hard and soft interrupts.::

- rcu: hardirqs softirqs csw/system
- rcu: number: xx xx 0
- rcu: cputime: xx xx 0 ==> 2500(ms)
+ rcu: hardirqs softirqs csw/system
+ rcu: number: xx xx 0
+ rcu: cputime: xx xx 0 ==> 2500(ms)

Here, the number and CPU time of hard interrupts are all non-zero,
but the number of context switches and the in-kernel CPU time consumed
--
2.25.1