Re: [PATCH] Documentation/sysctl: document max_rcu_stall_to_panic

[Jonathan Corbet]

Joel Savitz <jsavitz@xxxxxxxxxx> writes:

> Friendly ping.

This was waiting for an ack from an RCU person.  Looking now, though, I
see that you didn't copy any RCU people.  Adding Paul and the author of
the patch you reference (and appending patch below).

Thanks,

jon

Joel Savitz <jsavitz@xxxxxxxxxx> (March 24) (kernel lwn)
Subject: [PATCH] Documentation/sysctl: document max_rcu_stall_to_panic
To: linux-kernel@xxxxxxxxxxxxxxx
Cc: Joel Savitz <jsavitz@xxxxxxxxxx>, Jonathan Corbet <corbet@xxxxxxx>, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, Huang Ying <ying.huang@xxxxxxxxx>, Eric Biggers <ebiggers@xxxxxxxxxx>, Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>, Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>, Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>, "Jason A. Donenfeld" <Jason@xxxxxxxxx>, Daniel Borkmann <daniel@xxxxxxxxxxxxx>, Rob Herring <robh@xxxxxxxxxx>, Wang Qing <wangqing@xxxxxxxx>, linux-doc@xxxxxxxxxxxxxxx
Date: Thu, 24 Mar 2022 18:11:56 -0400

commit dfe564045c65 ("rcu: Panic after fixed number of stalls")
introduced a new systctl but no accompanying documentation.

Add a simple entry to the documentation.

Signed-off-by: Joel Savitz <jsavitz@xxxxxxxxxx>
---
 Documentation/admin-guide/sysctl/kernel.rst | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 803c60bf21d3..4e48139b9a34 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -781,6 +781,13 @@ is useful to define the root cause of RCU stalls using a vmcore.
 1 panic() after printing RCU stall messages.
 = ============================================================

+max_rcu_stall_to_panic
+======================
+
+When ``panic_on_rcu_stall`` is set to 1, this value determines the
+number of times that RCU can stall before panic() is called.
+
+When ``panic_on_rcu_stall`` is set to 0, this value is has no effect.

 perf_cpu_time_max_percent
 =========================