[PATCH v3 1/3] samples: introduce new samples subdir for cgroup

[Dmitry Rokosov]

Move the cgroup_event_listener for cgroup v1 to the samples directory.
This suggestion was proposed by Andrew Morton during the discussion [1].

Links:
    [1] - https://lore.kernel.org/all/20231106140934.3f5d4960141562fe8da53906@xxxxxxxxxxxxxxxxxxxx/

Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxxxxx>
---
 MAINTAINERS                                       |  1 +
 samples/Kconfig                                   |  6 ++++++
 samples/Makefile                                  |  1 +
 samples/cgroup/Makefile                           |  5 +++++
 {tools => samples}/cgroup/cgroup_event_listener.c |  0
 tools/cgroup/Makefile                             | 11 -----------
 6 files changed, 13 insertions(+), 11 deletions(-)
 create mode 100644 samples/cgroup/Makefile
 rename {tools => samples}/cgroup/cgroup_event_listener.c (100%)
 delete mode 100644 tools/cgroup/Makefile

diff --git a/MAINTAINERS b/MAINTAINERS
index d516295978a4..6a0a580c34dc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5243,6 +5243,7 @@ L:	linux-mm@xxxxxxxxx
 S:	Maintained
 F:	mm/memcontrol.c
 F:	mm/swap_cgroup.c
+F:	samples/cgroup/*
 F:	tools/testing/selftests/cgroup/memcg_protection.m
 F:	tools/testing/selftests/cgroup/test_kmem.c
 F:	tools/testing/selftests/cgroup/test_memcontrol.c
diff --git a/samples/Kconfig b/samples/Kconfig
index bf49ed0d7362..339c8e2ee749 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -287,6 +287,12 @@ config SAMPLE_KMEMLEAK
           Build a sample program which have explicitly leaks memory to test
           kmemleak
 
+config SAMPLE_CGROUP
+	bool "Build cgroup sample code"
+	depends on CGROUPS && CC_CAN_LINK && HEADERS_INSTALL
+	help
+	  Build samples that demonstrate the usage of the cgroup API.
+
 source "samples/rust/Kconfig"
 
 endif # SAMPLES
diff --git a/samples/Makefile b/samples/Makefile
index 0a551c2b33f4..b85fa64390c5 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -3,6 +3,7 @@
 
 subdir-$(CONFIG_SAMPLE_AUXDISPLAY)	+= auxdisplay
 subdir-$(CONFIG_SAMPLE_ANDROID_BINDERFS) += binderfs
+subdir-$(CONFIG_SAMPLE_CGROUP) += cgroup
 obj-$(CONFIG_SAMPLE_CONFIGFS)		+= configfs/
 obj-$(CONFIG_SAMPLE_CONNECTOR)		+= connector/
 obj-$(CONFIG_SAMPLE_FANOTIFY_ERROR)	+= fanotify/
diff --git a/samples/cgroup/Makefile b/samples/cgroup/Makefile
new file mode 100644
index 000000000000..deef4530f5e7
--- /dev/null
+++ b/samples/cgroup/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+userprogs-always-y += cgroup_event_listener
+
+userccflags += -I usr/include
diff --git a/tools/cgroup/cgroup_event_listener.c b/samples/cgroup/cgroup_event_listener.c
similarity index 100%
rename from tools/cgroup/cgroup_event_listener.c
rename to samples/cgroup/cgroup_event_listener.c
diff --git a/tools/cgroup/Makefile b/tools/cgroup/Makefile
deleted file mode 100644
index ffca068e4a76..000000000000
--- a/tools/cgroup/Makefile
+++ /dev/null
@@ -1,11 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-# Makefile for cgroup tools
-
-CFLAGS = -Wall -Wextra
-
-all: cgroup_event_listener
-%: %.c
-	$(CC) $(CFLAGS) -o $@ $^
-
-clean:
-	$(RM) cgroup_event_listener
-- 
2.36.0