[PATCH] build: output a dependency log in build directory

Bruce Richardson
2024-07-30T14:55:20Z

As meson processes our DPDK source tree it manages dependencies
specified by each individual driver. To enable future analysis of the
dependency links between components, log the dependencies of each DPDK
component as it gets processed. This could potentially allow other tools
to automatically enable or disable components based on the desired end
components to be built, e.g. if the user requests net/ice, ensure that
common/iavf is also enabled in the drivers.

The output file produced is in "dot" or "graphviz" format, which allows
producing a graphical representation of the DPDK dependency tree if so
desired. For example: "dot -Tpng -O build/deps.dot" to produce the
image file "build/deps.dot.png".

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
app/meson.build | 1 +
buildtools/log-deps.py | 43 ++++++++++++++++++++++++++++++++++++++++++
buildtools/meson.build | 2 ++
drivers/meson.build | 1 +
lib/meson.build | 1 +
5 files changed, 48 insertions(+)
create mode 100644 buildtools/log-deps.py

diff --git a/app/meson.build b/app/meson.build
index 5b2c80c7a1..6afa457f4c 100644
--- a/app/meson.build
+++ b/app/meson.build
@@ -76,6 +76,7 @@ foreach app:apps

if build
subdir(name)
+ run_command([log_deps_cmd, name, deps])
if not build and require_apps
error('Cannot build explicitly requested app "@0@".\n'.format(name)
+ '\tReason: ' + reason)
diff --git a/buildtools/log-deps.py b/buildtools/log-deps.py
new file mode 100644
index 0000000000..a4331fa15b
--- /dev/null
+++ b/buildtools/log-deps.py
@@ -0,0 +1,43 @@
+#! /usr/bin/env python3
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2024 Intel Corporation
+
+"""Utility script to build up a list of dependencies from meson."""
+
+import os
+import sys
+
+
+def file_to_list(filename):
+ """Read file into a list of strings."""
+ with open(filename) as f:
+ return f.readlines()
+
+
+def list_to_file(filename, lines):
+ """Write a list of strings out to a file."""
+ with open(filename, 'w') as f:
+ f.writelines(lines)
+
+
+depsfile = f'{os.environ["MESON_BUILD_ROOT"]}/deps.dot'
+
+# to reset the deps file on each build, the script is called without any params
+if len(sys.argv) == 1:
+ os.remove(depsfile)
+ sys.exit(0)
+
+try:
+ contents = file_to_list(depsfile)
+except FileNotFoundError:
+ contents = ['digraph {\n', '}\n']
+
+component = sys.argv[1]
+if len(sys.argv) > 2:
+ contents[-1] = f'"{component}" -> {{ "{"\", \"".join(sys.argv[2:])}" }}\n'
+else:
+ contents[-1] = f'"{component}"\n'
+
+contents.append('}\n')
+
+list_to_file(depsfile, contents)
diff --git a/buildtools/meson.build b/buildtools/meson.build
index 3adf34e1a8..332f0f3d38 100644
--- a/buildtools/meson.build
+++ b/buildtools/meson.build
@@ -24,6 +24,8 @@ get_numa_count_cmd = py3 + files('get-numa-count.py')
get_test_suites_cmd = py3 + files('get-test-suites.py')
has_hugepages_cmd = py3 + files('has-hugepages.py')
cmdline_gen_cmd = py3 + files('dpdk-cmdline-gen.py')
+log_deps_cmd = py3 + files('log-deps.py')
+run_command(log_deps_cmd) # call with no parameters to reset the file

# install any build tools that end-users might want also
install_data([
diff --git a/drivers/meson.build b/drivers/meson.build
index 66931d4241..44935e067c 100644
--- a/drivers/meson.build
+++ b/drivers/meson.build
@@ -154,6 +154,7 @@ foreach subpath:subdirs
if build
# pull in driver directory which should update all the local variables
subdir(drv_path)
+ run_command([log_deps_cmd, drv_path.underscorify(), deps])

if dpdk_conf.get('RTE_IOVA_IN_MBUF') == 0 and require_iova_in_mbuf
build = false
diff --git a/lib/meson.build b/lib/meson.build
index 162287753f..da2815465f 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -160,6 +160,7 @@ foreach l:libraries

if build
subdir(l)
+ run_command([log_deps_cmd, l, deps])
if not build and require_libs
error('Cannot build explicitly requested lib "@0@".\n'.format(name)
+'\tReason: ' + reason)
--
2.43.0