From 8bd4cc6712282161ab085cf87f34cc3a682f2bdc Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 31 May 2012 19:46:42 +0200
Subject: [PATCH] logind: properly clean up user cgroups when they run empty
 (cherry picked from commit
 8c8c43515cee56dfc2298998a9e5958308c46f99)

Conflicts:
	src/login/logind.c
---
 src/login/logind-session.c |    6 ++--
 src/login/logind-user.c    |    6 ++++
 src/login/logind.c         |   65 ++++++++++++++++++++++++++++++++++++++------
 src/login/logind.h         |    5 +++-
 4 files changed, 70 insertions(+), 12 deletions(-)

diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index 9bab7e8..49e1e5c 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -88,7 +88,7 @@ void session_free(Session *s) {
         }
 
         if (s->cgroup_path)
-                hashmap_remove(s->manager->cgroups, s->cgroup_path);
+                hashmap_remove(s->manager->session_cgroups, s->cgroup_path);
 
         free(s->cgroup_path);
         strv_free(s->controllers);
@@ -527,7 +527,7 @@ static int session_create_cgroup(Session *s) {
                 }
         }
 
-        hashmap_put(s->manager->cgroups, s->cgroup_path, s);
+        hashmap_put(s->manager->session_cgroups, s->cgroup_path, s);
 
         return 0;
 }
@@ -646,7 +646,7 @@ static int session_terminate_cgroup(Session *s) {
         STRV_FOREACH(k, s->user->manager->controllers)
                 cg_trim(*k, s->cgroup_path, true);
 
-        hashmap_remove(s->manager->cgroups, s->cgroup_path);
+        hashmap_remove(s->manager->session_cgroups, s->cgroup_path);
 
         free(s->cgroup_path);
         s->cgroup_path = NULL;
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index 39e8f9f..f813aac 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -75,6 +75,8 @@ void user_free(User *u) {
         while (u->sessions)
                 session_free(u->sessions);
 
+        if (u->cgroup_path)
+                hashmap_remove(u->manager->user_cgroups, u->cgroup_path);
         free(u->cgroup_path);
 
         free(u->service);
@@ -313,6 +315,8 @@ static int user_create_cgroup(User *u) {
                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
         }
 
+        hashmap_put(u->manager->user_cgroups, u->cgroup_path, u);
+
         return 0;
 }
 
@@ -417,6 +421,8 @@ static int user_terminate_cgroup(User *u) {
         STRV_FOREACH(k, u->manager->controllers)
                 cg_trim(*k, u->cgroup_path, true);
 
+        hashmap_remove(u->manager->user_cgroups, u->cgroup_path);
+
         free(u->cgroup_path);
         u->cgroup_path = NULL;
 
diff --git a/src/login/logind.c b/src/login/logind.c
index b2f6e65..c3f79df 100644
--- a/src/login/logind.c
+++ b/src/login/logind.c
@@ -58,12 +58,15 @@ Manager *manager_new(void) {
         m->users = hashmap_new(trivial_hash_func, trivial_compare_func);
         m->inhibitors = hashmap_new(string_hash_func, string_compare_func);
 
-        m->cgroups = hashmap_new(string_hash_func, string_compare_func);
+        m->user_cgroups = hashmap_new(string_hash_func, string_compare_func);
+        m->session_cgroups = hashmap_new(string_hash_func, string_compare_func);
+
         m->session_fds = hashmap_new(trivial_hash_func, trivial_compare_func);
         m->inhibitor_fds = hashmap_new(trivial_hash_func, trivial_compare_func);
 
         if (!m->devices || !m->seats || !m->sessions || !m->users || !m->inhibitors ||
-            !m->cgroups || !m->session_fds || !m->inhibitor_fds) {
+            !m->user_cgroups || !m->session_cgroups ||
+            !m->session_fds || !m->inhibitor_fds) {
                 manager_free(m);
                 return NULL;
         }
@@ -119,7 +122,9 @@ void manager_free(Manager *m) {
         hashmap_free(m->users);
         hashmap_free(m->inhibitors);
 
-        hashmap_free(m->cgroups);
+        hashmap_free(m->user_cgroups);
+        hashmap_free(m->session_cgroups);
+
         hashmap_free(m->session_fds);
         hashmap_free(m->inhibitor_fds);
 
@@ -864,7 +869,7 @@ int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **sess
         assert(cgroup);
         assert(session);
 
-        s = hashmap_get(m->cgroups, cgroup);
+        s = hashmap_get(m->session_cgroups, cgroup);
         if (s) {
                 *session = s;
                 return 1;
@@ -888,7 +893,7 @@ int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **sess
 
                 *e = 0;
 
-                s = hashmap_get(m->cgroups, p);
+                s = hashmap_get(m->session_cgroups, p);
                 if (s) {
                         free(p);
                         *session = s;
@@ -897,6 +902,47 @@ int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **sess
         }
 }
 
+int manager_get_user_by_cgroup(Manager *m, const char *cgroup, User **user) {
+        User *u;
+        char *p;
+
+        assert(m);
+        assert(cgroup);
+        assert(user);
+
+        u = hashmap_get(m->user_cgroups, cgroup);
+        if (u) {
+                *user = u;
+                return 1;
+        }
+
+        p = strdup(cgroup);
+        if (!p) {
+                log_error("Out of memory.");
+                return -ENOMEM;
+        }
+
+        for (;;) {
+                char *e;
+
+                e = strrchr(p, '/');
+                if (!e || e == p) {
+                        free(p);
+                        *user = NULL;
+                        return 0;
+                }
+
+                *e = 0;
+
+                u = hashmap_get(m->user_cgroups, p);
+                if (u) {
+                        free(p);
+                        *user = u;
+                        return 1;
+                }
+        }
+}
+
 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **session) {
         char *p;
         int r;
@@ -917,13 +963,16 @@ int manager_get_session_by_pid(Manager *m, pid_t pid, Session **session) {
 
 void manager_cgroup_notify_empty(Manager *m, const char *cgroup) {
         Session *s;
+        User *u;
         int r;
 
         r = manager_get_session_by_cgroup(m, cgroup, &s);
-        if (r <= 0)
-                return;
+        if (r > 0)
+                session_add_to_gc_queue(s);
 
-        session_add_to_gc_queue(s);
+        r = manager_get_user_by_cgroup(m, cgroup, &u);
+        if (r > 0)
+                user_add_to_gc_queue(u);
 }
 
 static void manager_pipe_notify_eof(Manager *m, int fd) {
diff --git a/src/login/logind.h b/src/login/logind.h
index e03ef31..4e5cb01 100644
--- a/src/login/logind.h
+++ b/src/login/logind.h
@@ -78,7 +78,9 @@ struct Manager {
         unsigned long session_counter;
         unsigned long inhibit_counter;
 
-        Hashmap *cgroups;
+        Hashmap *session_cgroups;
+        Hashmap *user_cgroups;
+
         Hashmap *session_fds;
         Hashmap *inhibitor_fds;
 
@@ -132,6 +134,7 @@ void manager_gc(Manager *m, bool drop_not_started);
 
 int manager_get_idle_hint(Manager *m, dual_timestamp *t);
 
+int manager_get_user_by_cgroup(Manager *m, const char *cgroup, User **user);
 int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **session);
 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **session);