The patch titled
Task Control Groups: add cgroup_clone() interface
has been removed from the -mm tree. Its filename was
task-containersv11-add-container_clone-interface.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: Task Control Groups: add cgroup_clone() interface
From: Paul Menage <menage@xxxxxxxxxx>
Add support for cgroup_clone(), a way to create new cgroups intended to
be used for systems such as namespace unsharing. A new subsystem callback,
post_clone(), is added to allow subsystems to automatically configure cloned
cgroups.
Signed-off-by: Paul Menage <menage@xxxxxxxxxx>
Cc: Serge E. Hallyn <serue@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Dave Hansen <haveblue@xxxxxxxxxx>
Cc: Balbir Singh <balbir@xxxxxxxxxx>
Cc: Paul Jackson <pj@xxxxxxx>
Cc: Kirill Korotaev <dev@xxxxxxxxxx>
Cc: Herbert Poetzl <herbert@xxxxxxxxxxxx>
Cc: Srivatsa Vaddagiri <vatsa@xxxxxxxxxx>
Cc: Cedric Le Goater <clg@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/cgroups.txt | 7 +
include/linux/cgroup.h | 3
kernel/cgroup.c | 135 ++++++++++++++++++++++++++++++++++++
3 files changed, 145 insertions(+)
diff -puN Documentation/cgroups.txt~task-containersv11-add-container_clone-interface Documentation/cgroups.txt
--- a/Documentation/cgroups.txt~task-containersv11-add-container_clone-interface
+++ a/Documentation/cgroups.txt
@@ -504,6 +504,13 @@ include/linux/cgroup.h for details). No
method can return an error code, the error code is currently not
always handled well.
+void post_clone(struct cgroup_subsys *ss, struct cgroup *cont)
+
+Called at the end of cgroup_clone() to do any paramater
+initialization which might be required before a task could attach. For
+example in cpusets, no task may attach before 'cpus' and 'mems' are set
+up.
+
void bind(struct cgroup_subsys *ss, struct cgroup *root)
LL=callback_mutex
diff -puN include/linux/cgroup.h~task-containersv11-add-container_clone-interface include/linux/cgroup.h
--- a/include/linux/cgroup.h~task-containersv11-add-container_clone-interface
+++ a/include/linux/cgroup.h
@@ -182,6 +182,7 @@ struct cgroup_subsys {
void (*exit)(struct cgroup_subsys *ss, struct task_struct *task);
int (*populate)(struct cgroup_subsys *ss,
struct cgroup *cont);
+ void (*post_clone)(struct cgroup_subsys *ss, struct cgroup *cont);
void (*bind)(struct cgroup_subsys *ss, struct cgroup *root);
int subsys_id;
int active;
@@ -221,6 +222,8 @@ static inline struct cgroup* task_cgroup
int cgroup_path(const struct cgroup *cont, char *buf, int buflen);
+int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *ss);
+
#else /* !CONFIG_CGROUPS */
static inline int cgroup_init_early(void) { return 0; }
diff -puN kernel/cgroup.c~task-containersv11-add-container_clone-interface kernel/cgroup.c
--- a/kernel/cgroup.c~task-containersv11-add-container_clone-interface
+++ a/kernel/cgroup.c
@@ -1708,3 +1708,138 @@ void cgroup_exit(struct task_struct *tsk
tsk->cgroups = init_task.cgroups;
task_unlock(tsk);
}
+
+/**
+ * cgroup_clone - duplicate the current cgroup in the hierarchy
+ * that the given subsystem is attached to, and move this task into
+ * the new child
+ */
+int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys)
+{
+ struct dentry *dentry;
+ int ret = 0;
+ char nodename[MAX_CGROUP_TYPE_NAMELEN];
+ struct cgroup *parent, *child;
+ struct inode *inode;
+ struct css_set *cg;
+ struct cgroupfs_root *root;
+ struct cgroup_subsys *ss;
+
+ /* We shouldn't be called by an unregistered subsystem */
+ BUG_ON(!subsys->active);
+
+ /* First figure out what hierarchy and cgroup we're dealing
+ * with, and pin them so we can drop cgroup_mutex */
+ mutex_lock(&cgroup_mutex);
+ again:
+ root = subsys->root;
+ if (root == &rootnode) {
+ printk(KERN_INFO
+ "Not cloning cgroup for unused subsystem %s\n",
+ subsys->name);
+ mutex_unlock(&cgroup_mutex);
+ return 0;
+ }
+ cg = &tsk->cgroups;
+ parent = task_cgroup(tsk, subsys->subsys_id);
+
+ snprintf(nodename, MAX_CGROUP_TYPE_NAMELEN, "node_%d", tsk->pid);
+
+ /* Pin the hierarchy */
+ atomic_inc(&parent->root->sb->s_active);
+
+ mutex_unlock(&cgroup_mutex);
+
+ /* Now do the VFS work to create a cgroup */
+ inode = parent->dentry->d_inode;
+
+ /* Hold the parent directory mutex across this operation to
+ * stop anyone else deleting the new cgroup */
+ mutex_lock(&inode->i_mutex);
+ dentry = lookup_one_len(nodename, parent->dentry, strlen(nodename));
+ if (IS_ERR(dentry)) {
+ printk(KERN_INFO
+ "Couldn't allocate dentry for %s: %ld\n", nodename,
+ PTR_ERR(dentry));
+ ret = PTR_ERR(dentry);
+ goto out_release;
+ }
+
+ /* Create the cgroup directory, which also creates the cgroup */
+ ret = vfs_mkdir(inode, dentry, S_IFDIR | 0755);
+ child = __d_cont(dentry);
+ dput(dentry);
+ if (ret) {
+ printk(KERN_INFO
+ "Failed to create cgroup %s: %d\n", nodename,
+ ret);
+ goto out_release;
+ }
+
+ if (!child) {
+ printk(KERN_INFO
+ "Couldn't find new cgroup %s\n", nodename);
+ ret = -ENOMEM;
+ goto out_release;
+ }
+
+ /* The cgroup now exists. Retake cgroup_mutex and check
+ * that we're still in the same state that we thought we
+ * were. */
+ mutex_lock(&cgroup_mutex);
+ if ((root != subsys->root) ||
+ (parent != task_cgroup(tsk, subsys->subsys_id))) {
+ /* Aargh, we raced ... */
+ mutex_unlock(&inode->i_mutex);
+
+ deactivate_super(parent->root->sb);
+ /* The cgroup is still accessible in the VFS, but
+ * we're not going to try to rmdir() it at this
+ * point. */
+ printk(KERN_INFO
+ "Race in cgroup_clone() - leaking cgroup %s\n",
+ nodename);
+ goto again;
+ }
+
+ /* do any required auto-setup */
+ for_each_subsys(root, ss) {
+ if (ss->post_clone)
+ ss->post_clone(ss, child);
+ }
+
+ /* All seems fine. Finish by moving the task into the new cgroup */
+ ret = attach_task(child, tsk);
+ mutex_unlock(&cgroup_mutex);
+
+ out_release:
+ mutex_unlock(&inode->i_mutex);
+ deactivate_super(parent->root->sb);
+ return ret;
+}
+
+/*
+ * See if "cont" is a descendant of the current task's cgroup in
+ * the appropriate hierarchy
+ *
+ * If we are sending in dummytop, then presumably we are creating
+ * the top cgroup in the subsystem.
+ *
+ * Called only by the ns (nsproxy) cgroup.
+ */
+int cgroup_is_descendant(const struct cgroup *cont)
+{
+ int ret;
+ struct cgroup *target;
+ int subsys_id;
+
+ if (cont == dummytop)
+ return 1;
+
+ get_first_subsys(cont, NULL, &subsys_id);
+ target = task_cgroup(current, subsys_id);
+ while (cont != target && cont!= cont->top_cgroup)
+ cont = cont->parent;
+ ret = (cont == target);
+ return ret;
+}
_
Patches currently in -mm which might be from menage@xxxxxxxxxx are
origin.patch
memory-controller-add-documentation.patch
memory-controller-resource-counters-v7.patch
memory-controller-containers-setup-v7.patch
memory-controller-accounting-setup-v7.patch
memory-controller-memory-accounting-v7.patch
memory-controller-task-migration-v7.patch
memory-controller-add-per-container-lru-and-reclaim-v7.patch
memory-controller-add-per-container-lru-and-reclaim-v7-fix.patch
memory-controller-improve-user-interface.patch
memory-controller-oom-handling-v7.patch
memory-controller-oom-handling-v7-vs-oom-killer-stuff.patch
memory-controller-add-switch-to-control-what-type-of-pages-to-limit-v7.patch
memory-controller-add-switch-to-control-what-type-of-pages-to-limit-v7-fix-2.patch
memory-controller-make-page_referenced-container-aware-v7.patch
memory-controller-make-charging-gfp-mask-aware.patch
bugfix-for-memory-cgroup-controller-charge-refcnt-race-fix.patch
bugfix-for-memory-cgroup-controller-fix-error-handling-path-in-mem_charge_cgroup.patch
bugfix-for-memory-controller-add-helper-function-for-assigning-cgroup-to-page.patch
bugfix-for-memory-cgroup-controller-avoid-pagelru-page-in-mem_cgroup_isolate_pages.patch
bugfix-for-memory-cgroup-controller-migration-under-memory-controller-fix.patch
add-a-refcount-check-in-dput.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
