[PATCH 4/4] docs: admin-guide: add IGNORE_DIRS example for cscope

[Cheng-Han Wu <hank20010209@gmail.com>]

The workload tracing guide shows how to build a cscope database by
running cscope command directly. The kernel build system also provides
a cscope target, which supports IGNORE_DIRS for excluding directories
from the generated database.

Mention make cscope and show how to exclude Documentation/ as an example.

Signed-off-by: Cheng-Han Wu <hank20010209@gmail.com>
---
 Documentation/admin-guide/workload-tracing.rst | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/admin-guide/workload-tracing.rst b/Documentation/admin-guide/workload-tracing.rst
index c49c2a00a8b8..314e5f03474e 100644
--- a/Documentation/admin-guide/workload-tracing.rst
+++ b/Documentation/admin-guide/workload-tracing.rst
@@ -202,6 +202,15 @@ database. To get out of this mode press ctrl+d. -p option is used to
 specify the number of file path components to display. -p10 is optimal
 for browsing kernel sources.
 
+Alternatively, the kernel build system can generate the cscope database::
+
+  make cscope
+
+To exclude directories from the generated database, pass IGNORE_DIRS to
+the cscope target. For example, to exclude Documentation/, run::
+
+  make IGNORE_DIRS="Documentation" cscope
+
 What is perf and how do we use it?
 ==================================
 
-- 
2.52.0