+ samples-introduce-new-samples-subdir-for-cgroup.patch added to mm-unstable branch

+ samples-introduce-new-samples-subdir-for-cgroup.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: samples: introduce new samples subdir for cgroup
has been added to the -mm mm-unstable branch.  Its filename is
     samples-introduce-new-samples-subdir-for-cgroup.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/samples-introduce-new-samples-subdir-for-cgroup.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Dmitry Rokosov <ddrokosov@salutedevices.com>
Subject: samples: introduce new samples subdir for cgroup
Date: Thu, 23 Nov 2023 10:19:43 +0300

Patch series "samples: introduce cgroup events listeners", v3.

To begin with, this patch series relocates the cgroup example code to the
samples/cgroup directory, which is the appropriate location for such code
snippets.

Furthermore, a new memcg events listener is introduced.  This listener is
a simple yet effective tool for monitoring memory events and managing
counter changes during runtime.

Additionally, as per Andrew Morton's suggestion, a helpful reminder
comment is included in the memcontrol implementation.  This comment serves
to ensure that the samples code is updated whenever new events are added.


This patch (of 3):

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

Link: https://lore.kernel.org/all/20231106140934.3f5d4960141562fe8da53906@linux-foundation.org/ [1]
Link: https://lkml.kernel.org/r/20231123071945.25811-1-ddrokosov@salutedevices.com
Link: https://lkml.kernel.org/r/20231123071945.25811-2-ddrokosov@salutedevices.com
Signed-off-by: Dmitry Rokosov <ddrokosov@salutedevices.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 MAINTAINERS             |    1 +
 samples/Kconfig         |    6 ++++++
 samples/Makefile        |    1 +
 samples/cgroup/Makefile |    5 +++++
 tools/cgroup/Makefile   |   11 -----------
 5 files changed, 13 insertions(+), 11 deletions(-)

--- a/MAINTAINERS~samples-introduce-new-samples-subdir-for-cgroup
+++ a/MAINTAINERS
@@ -5352,6 +5352,7 @@ L:	linux-mm@kvack.org
 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_hugetlb_memcg.c
 F:	tools/testing/selftests/cgroup/test_kmem.c
--- /dev/null
+++ a/samples/cgroup/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+userprogs-always-y += cgroup_event_listener
+
+userccflags += -I usr/include
--- a/samples/Kconfig~samples-introduce-new-samples-subdir-for-cgroup
+++ a/samples/Kconfig
@@ -285,6 +285,12 @@ 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
--- a/samples/Makefile~samples-introduce-new-samples-subdir-for-cgroup
+++ a/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/
--- 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
_

Patches currently in -mm which might be from ddrokosov@salutedevices.com are

mm-memcg-print-out-cgroup-ino-in-the-memcg-tracepoints.patch
mm-memcg-introduce-new-event-to-trace-shrink_memcg.patch
samples-introduce-new-samples-subdir-for-cgroup.patch
samples-cgroup-introduce-memcg-memoryevents-listener.patch
mm-memcg-add-reminder-comment-for-the-memcg-v2-events.patch