From: Lennart Poettering <lennart@poettering.net>
Date: Wed, 17 Jan 2018 14:39:39 +0000 (+0100)
Subject: cgroup: when querying the number of tasks in the root slice use the pid_max sysctl
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=a696ccac5a53620d1652b10218a7f62647a2c501;p=elogind.git

cgroup: when querying the number of tasks in the root slice use the pid_max sysctl

The root cgroup doesn't expose and properties in the "pids" cgroup
controller, hence we need to get the data from somewhere else.
---

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 2e70aa79a..153a0dda8 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -32,6 +32,7 @@
 #include "parse-util.h"
 #include "path-util.h"
 #include "process-util.h"
+//#include "procfs-util.h"
 //#include "special.h"
 #include "stdio-util.h"
 #include "string-table.h"
@@ -2330,6 +2331,10 @@ int unit_get_tasks_current(Unit *u, uint64_t *ret) {
         if ((u->cgroup_realized_mask & CGROUP_MASK_PIDS) == 0)
                 return -ENODATA;
 
+        /* The root cgroup doesn't expose this information, let's get it from /proc instead */
+        if (unit_has_root_cgroup(u))
+                return procfs_tasks_get_current(ret);
+
         r = cg_get_attribute("pids", u->cgroup_path, "pids.current", &v);
         if (r == -ENOENT)
                 return -ENODATA;