Merge pull request #3965 from htejun/systemd-controller-on-unified

6 files changed, 28 insertions, 20 deletions

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index ca3c3366f3..086cd7a789 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -665,7 +665,7 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
                 bool has_weight = cgroup_context_has_cpu_weight(c);
                 bool has_shares = cgroup_context_has_cpu_shares(c);
 
-                if (cg_unified() > 0) {
+                if (cg_all_unified() > 0) {
                         uint64_t weight;
 
                         if (has_weight)
@@ -846,7 +846,7 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
         }
 
         if ((mask & CGROUP_MASK_MEMORY) && !is_root) {
-                if (cg_unified() > 0) {
+                if (cg_all_unified() > 0) {
                         uint64_t max = c->memory_max;
 
                         if (cgroup_context_has_unified_memory_config(c))
@@ -1019,7 +1019,7 @@ CGroupMask unit_get_own_mask(Unit *u) {
                 e = unit_get_exec_context(u);
                 if (!e ||
                     exec_context_maintains_privileges(e) ||
-                    cg_unified() > 0)
+                    cg_all_unified() > 0)
                         return _CGROUP_MASK_ALL;
         }
 
@@ -1245,7 +1245,7 @@ int unit_watch_cgroup(Unit *u) {
                 return 0;
 
         /* Only applies to the unified hierarchy */
-        r = cg_unified();
+        r = cg_unified(SYSTEMD_CGROUP_CONTROLLER);
         if (r < 0)
                 return log_unit_error_errno(u, r, "Failed detect whether the unified hierarchy is used: %m");
         if (r == 0)
@@ -1645,7 +1645,7 @@ int unit_watch_all_pids(Unit *u) {
         if (!u->cgroup_path)
                 return -ENOENT;
 
-        if (cg_unified() > 0) /* On unified we can use proper notifications */
+        if (cg_unified(SYSTEMD_CGROUP_CONTROLLER) > 0) /* On unified we can use proper notifications */
                 return 0;
 
         return unit_watch_pids_in_path(u, u->cgroup_path);
@@ -1718,7 +1718,7 @@ static int on_cgroup_inotify_event(sd_event_source *s, int fd, uint32_t revents,
 int manager_setup_cgroup(Manager *m) {
         _cleanup_free_ char *path = NULL;
         CGroupController c;
-        int r, unified;
+        int r, all_unified, systemd_unified;
         char *e;
 
         assert(m);
@@ -1755,11 +1755,17 @@ int manager_setup_cgroup(Manager *m) {
         if (r < 0)
                 return log_error_errno(r, "Cannot find cgroup mount point: %m");
 
-        unified = cg_unified();
-        if (unified < 0)
-                return log_error_errno(r, "Couldn't determine if we are running in the unified hierarchy: %m");
-        if (unified > 0)
+        all_unified = cg_all_unified();
+        systemd_unified = cg_unified(SYSTEMD_CGROUP_CONTROLLER);
+
+        if (all_unified < 0 || systemd_unified < 0)
+                return log_error_errno(all_unified < 0 ? all_unified : systemd_unified,
+                                       "Couldn't determine if we are running in the unified hierarchy: %m");
+
+        if (all_unified > 0)
                 log_debug("Unified cgroup hierarchy is located at %s.", path);
+        else if (systemd_unified > 0)
+                log_debug("Unified cgroup hierarchy is located at %s. Controllers are on legacy hierarchies.", path);
         else
                 log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
 
@@ -1767,7 +1773,7 @@ int manager_setup_cgroup(Manager *m) {
                 const char *scope_path;
 
                 /* 3. Install agent */
-                if (unified) {
+                if (systemd_unified) {
 
                         /* In the unified hierarchy we can get
                          * cgroup empty notifications via inotify. */
@@ -1827,7 +1833,7 @@ int manager_setup_cgroup(Manager *m) {
                         return log_error_errno(errno, "Failed to open pin file: %m");
 
                 /* 6.  Always enable hierarchical support if it exists... */
-                if (!unified)
+                if (!all_unified)
                         (void) cg_set_attribute("memory", "/", "memory.use_hierarchy", "1");
         }
 
@@ -1953,7 +1959,7 @@ int unit_get_memory_current(Unit *u, uint64_t *ret) {
         if ((u->cgroup_realized_mask & CGROUP_MASK_MEMORY) == 0)
                 return -ENODATA;
 
-        if (cg_unified() <= 0)
+        if (cg_all_unified() <= 0)
                 r = cg_get_attribute("memory", u->cgroup_path, "memory.usage_in_bytes", &v);
         else
                 r = cg_get_attribute("memory", u->cgroup_path, "memory.current", &v);
@@ -1998,7 +2004,7 @@ static int unit_get_cpu_usage_raw(Unit *u, nsec_t *ret) {
         if (!u->cgroup_path)
                 return -ENODATA;
 
-        if (cg_unified() > 0) {
+        if (cg_all_unified() > 0) {
                 const char *keys[] = { "usage_usec", NULL };
                 _cleanup_free_ char *val = NULL;
                 uint64_t us;
diff --git a/src/core/manager.c b/src/core/manager.c
index 6f2477eef4..7576d038a2 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -771,7 +771,7 @@ static int manager_setup_cgroups_agent(Manager *m) {
         if (!MANAGER_IS_SYSTEM(m))
                 return 0;
 
-        if (cg_unified() > 0) /* We don't need this anymore on the unified hierarchy */
+        if (cg_unified(SYSTEMD_CGROUP_CONTROLLER) > 0) /* We don't need this anymore on the unified hierarchy */
                 return 0;
 
         if (m->cgroups_agent_fd < 0) {
diff --git a/src/core/mount-setup.c b/src/core/mount-setup.c
index 5d8ab0ec70..ca63a93e8b 100644
--- a/src/core/mount-setup.c
+++ b/src/core/mount-setup.c
@@ -99,10 +99,12 @@ static const MountPoint mount_table[] = {
           cg_is_unified_wanted, MNT_FATAL|MNT_IN_CONTAINER },
         { "tmpfs",       "/sys/fs/cgroup",            "tmpfs",      "mode=755",                MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME,
           cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+        { "cgroup",      "/sys/fs/cgroup/systemd",    "cgroup2",    NULL,                      MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          cg_is_unified_systemd_controller_wanted, MNT_IN_CONTAINER },
         { "cgroup",      "/sys/fs/cgroup/systemd",    "cgroup",     "none,name=systemd,xattr", MS_NOSUID|MS_NOEXEC|MS_NODEV,
-          cg_is_legacy_wanted, MNT_IN_CONTAINER           },
+          cg_is_legacy_systemd_controller_wanted, MNT_IN_CONTAINER           },
         { "cgroup",      "/sys/fs/cgroup/systemd",    "cgroup",     "none,name=systemd",       MS_NOSUID|MS_NOEXEC|MS_NODEV,
-          cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+          cg_is_legacy_systemd_controller_wanted, MNT_FATAL|MNT_IN_CONTAINER },
         { "pstore",      "/sys/fs/pstore",            "pstore",     NULL,                      MS_NOSUID|MS_NOEXEC|MS_NODEV,
           NULL,          MNT_NONE                   },
 #ifdef ENABLE_EFI
diff --git a/src/core/scope.c b/src/core/scope.c
index b278aed3d6..65fa65493b 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -441,7 +441,7 @@ static void scope_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 
         /* If the PID set is empty now, then let's finish this off
            (On unified we use proper notifications) */
-        if (cg_unified() <= 0 && set_isempty(u->pids))
+        if (cg_unified(SYSTEMD_CGROUP_CONTROLLER) <= 0 && set_isempty(u->pids))
                 scope_notify_cgroup_empty_event(u);
 }
 
diff --git a/src/core/service.c b/src/core/service.c
index 1951ba9222..969c62bd83 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -2869,7 +2869,7 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 
         /* If the PID set is empty now, then let's finish this off
            (On unified we use proper notifications) */
-        if (cg_unified() <= 0 && set_isempty(u->pids))
+        if (cg_unified(SYSTEMD_CGROUP_CONTROLLER) <= 0 && set_isempty(u->pids))
                 service_notify_cgroup_empty_event(u);
 }
 
diff --git a/src/core/unit.c b/src/core/unit.c
index 4b8d81c3f1..c58c501bc3 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -3726,7 +3726,7 @@ int unit_kill_context(
                          * there we get proper events. Hence rely on
                          * them.*/
 
-                        if  (cg_unified() > 0 ||
+                        if  (cg_unified(SYSTEMD_CGROUP_CONTROLLER) > 0 ||
                              (detect_container() == 0 && !unit_cgroup_delegate(u)))
                                 wait_for_exit = true;