From 8742fc797d827ff92831af7d8af353e6bb073ddc Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 5 Nov 2013 22:17:03 +0100
Subject: [PATCH] shutdown: trim the cgroup tree on loop iteration
This way we leave the cgroup empty before exiting in a container which
makes sure the container manager will get cgroup notification event
https://bugs.freedesktop.org/show_bug.cgi?id=68370
https://bugzilla.redhat.com/show_bug.cgi?id=988883
---
src/core/shutdown.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/src/core/shutdown.c b/src/core/shutdown.c
index 4709746..ea02b60 100644
--- a/src/core/shutdown.c
+++ b/src/core/shutdown.c
@@ -46,6 +46,7 @@
#include "virt.h"
#include "watchdog.h"
#include "killall.h"
+#include "cgroup-util.h"
#define FINALIZE_ATTEMPTS 50
@@ -131,12 +132,12 @@ static int pivot_to_new_root(void) {
}
int main(int argc, char *argv[]) {
- _cleanup_free_ char *line = NULL;
- int cmd, r;
- unsigned retries;
bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true;
bool in_container, use_watchdog = false;
+ _cleanup_free_ char *line = NULL, *cgroup = NULL;
char *arguments[3];
+ unsigned retries;
+ int cmd, r;
/* suppress shutdown status output if 'quiet' is used */
r = read_one_line_file("/proc/cmdline", &line);
@@ -186,6 +187,8 @@ int main(int argc, char *argv[]) {
goto error;
}
+ cg_get_root_path(&cgroup);
+
use_watchdog = !!getenv("WATCHDOG_USEC");
/* lock us into memory */
@@ -210,6 +213,13 @@ int main(int argc, char *argv[]) {
if (use_watchdog)
watchdog_ping();
+ /* Let's trim the cgroup tree on each iteration so
+ that we leave an empty cgroup tree around, so that
+ container managers get a nice notify event when we
+ are down */
+ if (cgroup)
+ cg_trim(SYSTEMD_CGROUP_CONTROLLER, cgroup, false);
+
if (need_umount) {
log_info("Unmounting file systems.");
r = umount_all(&changed);