vircgroup: introduce virCgroupNewParent

The current code uses virCgroupNew() as a single point of entry and
calls into virCgroupDetect() as well. Both have logic for several paths
which is difficult to figure out.

Extract the actually used code path from the two functions to make
it obvious what's happening in this case.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
index 97e15c0ab3a70c5ce618c6387f7033e336f34ca5..b11139bef1193b0cf7797ccb0ebb7138cf66046b 100644 (file)
--- a/src/util/vircgroup.c
+++ b/src/util/vircgroup.c
@@ -861,6 +861,40 @@ virCgroupSetPartitionSuffix(const char *path, char **res)
 }
 
 
+static int
+virCgroupNewFromParent(virCgroupPtr parent,
+                       const char *path,
+                       int controllers,
+                       virCgroupPtr *group)
+{
+    g_autoptr(virCgroup) new = g_new0(virCgroup, 1);
+
+    VIR_DEBUG("parent=%p path=%s controllers=%d group=%p",
+              parent, path, controllers, group);
+
+    if (virCgroupSetBackends(new) < 0)
+        return -1;
+
+    if (virCgroupCopyMounts(new, parent) < 0)
+        return -1;
+
+    if (virCgroupCopyPlacement(new, path, parent) < 0)
+        return -1;
+
+    if (virCgroupDetectPlacement(new, -1, path) < 0)
+        return -1;
+
+    if (virCgroupValidatePlacement(new, -1) < 0)
+        return -1;
+
+    if (virCgroupDetectControllers(new, controllers, parent) < 0)
+        return -1;
+
+    *group = g_steal_pointer(&new);
+    return 0;
+}
+
+
 /**
  * virCgroupNewPartition:
  * @path: path for the partition
@@ -910,7 +944,7 @@ virCgroupNewPartition(const char *path,
             return -1;
     }
 
-    if (virCgroupNew(-1, newPath, parent, controllers, &newGroup) < 0)
+    if (virCgroupNewFromParent(parent, newPath, controllers, &newGroup) < 0)
         return -1;
 
     if (parent) {
@@ -965,7 +999,7 @@ virCgroupNewDomainPartition(virCgroupPtr partition,
     if (virCgroupPartitionEscape(&grpname) < 0)
         return -1;
 
-    if (virCgroupNew(-1, grpname, partition, -1, &newGroup) < 0)
+    if (virCgroupNewFromParent(partition, grpname, -1, &newGroup) < 0)
         return -1;
 
     /*
@@ -1032,7 +1066,7 @@ virCgroupNewThread(virCgroupPtr domain,
                    (1 << VIR_CGROUP_CONTROLLER_CPUACCT) |
                    (1 << VIR_CGROUP_CONTROLLER_CPUSET));
 
-    if (virCgroupNew(-1, name, domain, controllers, &newGroup) < 0)
+    if (virCgroupNewFromParent(domain, name, controllers, &newGroup) < 0)
         return -1;
 
     if (virCgroupMakeGroup(domain, newGroup, create, VIR_CGROUP_THREAD) < 0)
@@ -1133,11 +1167,10 @@ virCgroupEnableMissingControllers(char *path,
         if (t)
             *t = '\0';
 
-        if (virCgroupNew(pidleader,
-                         path,
-                         parent,
-                         controllers,
-                         &tmp) < 0)
+        if (virCgroupNewFromParent(parent,
+                                   path,
+                                   controllers,
+                                   &tmp) < 0)
             return -1;
 
         if (virCgroupMakeGroup(parent, tmp, true, VIR_CGROUP_SYSTEMD) < 0)
@@ -2583,7 +2616,7 @@ virCgroupKillRecursiveInternal(virCgroupPtr group,
 
         VIR_DEBUG("Process subdir %s", ent->d_name);
 
-        if (virCgroupNew(-1, ent->d_name, group, -1, &subgroup) < 0)
+        if (virCgroupNewFromParent(group, ent->d_name, -1, &subgroup) < 0)
             return -1;
 
         if ((rc = virCgroupKillRecursiveInternal(subgroup, signum, pids,