2023-07-05 18:25:32

by Valentin Schneider

[permalink] [raw]
Subject: [RFC PATCH 05/14] tracing/filters: Document cpumask filtering

Cpumask, scalar and CPU fields can now be filtered by a user-provided
cpumask, document the syntax.

Signed-off-by: Valentin Schneider <[email protected]>
---
Documentation/trace/events.rst | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
index f5fcb8e1218f6..e9bc9f23891a0 100644
--- a/Documentation/trace/events.rst
+++ b/Documentation/trace/events.rst
@@ -219,6 +219,20 @@ the function "security_prepare_creds" and less than the end of that function.
The ".function" postfix can only be attached to values of size long, and can only
be compared with "==" or "!=".

+Cpumask fields or scalar fields that encode a CPU number can be filtered using
+a user-provided cpumask in cpulist format. The format is as follows::
+
+ MASK{$cpulist}
+
+Operators available to cpumask filtering are:
+
+& (intersection), ==, !=
+
+For example, this will filter events that have their .target_cpu field present
+in the given cpumask::
+
+ target_cpu & MASK{17-42}
+
5.2 Setting filters
-------------------

--
2.31.1