Add two extra arguments to cgroup_{can|cancel|post}_fork(). These
will be used to implement in-process resource control. The extra
arguments aren't used yet.
Signed-off-by: Tejun Heo <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Oleg Nesterov <[email protected]>
---
include/linux/cgroup-defs.h | 2 ++
include/linux/cgroup.h | 21 +++++++++++++++------
kernel/cgroup.c | 15 ++++++++++++---
kernel/fork.c | 7 ++++---
4 files changed, 33 insertions(+), 12 deletions(-)
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h
index 34b42f0..d3d1f92 100644
--- a/include/linux/cgroup-defs.h
+++ b/include/linux/cgroup-defs.h
@@ -542,6 +542,8 @@ static inline void cgroup_threadgroup_change_end(struct
task_struct *tsk)
#else /* CONFIG_CGROUPS */
+struct css_set;
+
#define CGROUP_SUBSYS_COUNT 0
static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk) {}
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 4717f43..ebcf21f 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -102,9 +102,12 @@ int proc_cgroup_show(struct seq_file *m, struct
pid_namespace *ns,
struct pid *pid, struct task_struct *tsk);
void cgroup_fork(struct task_struct *p);
-extern int cgroup_can_fork(struct task_struct *p);
-extern void cgroup_cancel_fork(struct task_struct *p);
-extern void cgroup_post_fork(struct task_struct *p);
+extern int cgroup_can_fork(struct task_struct *p, unsigned long clone_flags,
+ struct css_set **new_rgrp_csetp);
+extern void cgroup_cancel_fork(struct task_struct *p, unsigned long
clone_flags,
+ struct css_set *new_rgrp_cset);
+extern void cgroup_post_fork(struct task_struct *p, unsigned long clone_flags,
+ struct css_set *new_rgrp_cset);
void cgroup_exit(struct task_struct *p);
void cgroup_free(struct task_struct *p);
@@ -538,9 +541,15 @@ static inline int cgroupstats_build(struct cgroupstats
*stats,
struct dentry *dentry) { return -EINVAL; }
static inline void cgroup_fork(struct task_struct *p) {}
-static inline int cgroup_can_fork(struct task_struct *p) { return 0; }
-static inline void cgroup_cancel_fork(struct task_struct *p) {}
-static inline void cgroup_post_fork(struct task_struct *p) {}
+static inline int cgroup_can_fork(struct task_struct *p,
+ unsigned long clone_flags,
+ struct css_set **new_rgrp_csetp) { return 0; }
+static inline void cgroup_cancel_fork(struct task_struct *p,
+ unsigned long clone_flags,
+ struct css_set *new_rgrp_cset) {}
+static inline void cgroup_post_fork(struct task_struct *p,
+ unsigned long clone_flags,
+ struct css_set *new_rgrp_cset) {}
static inline void cgroup_exit(struct task_struct *p) {}
static inline void cgroup_free(struct task_struct *p) {}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 8ecb8d6..ac207ae 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5704,12 +5704,15 @@ void cgroup_fork(struct task_struct *child)
/**
* cgroup_can_fork - called on a new task before the process is exposed
* @child: the task in question.
+ * @clone_flags: CLONE_* flags for @child
+ * @new_rgrp_csetp: rgroup out parameter to be passed to post/cancel_fork
*
* This calls the subsystem can_fork() callbacks. If the can_fork() callback
* returns an error, the fork aborts with that error code. This allows for
* a cgroup subsystem to conditionally allow or deny new forks.
*/
-int cgroup_can_fork(struct task_struct *child)
+int cgroup_can_fork(struct task_struct *child, unsigned long clone_flags,
+ struct css_set **new_rgrp_csetp)
{
struct cgroup_subsys *ss;
int i, j, ret;
@@ -5736,11 +5739,14 @@ int cgroup_can_fork(struct task_struct *child)
/**
* cgroup_cancel_fork - called if a fork failed after cgroup_can_fork()
* @child: the task in question
+ * @clone_flags: CLONE_* flags for @child
+ * @new_rgrp_cset: *@new_rgrp_csetp from cgroup_can_fork()
*
* This calls the cancel_fork() callbacks if a fork failed *after*
* cgroup_can_fork() succeded.
*/
-void cgroup_cancel_fork(struct task_struct *child)
+void cgroup_cancel_fork(struct task_struct *child, unsigned long clone_flags,
+ struct css_set *new_rgrp_cset)
{
struct cgroup_subsys *ss;
int i;
@@ -5753,6 +5759,8 @@ void cgroup_cancel_fork(struct task_struct *child)
/**
* cgroup_post_fork - called on a new task after adding it to the task list
* @child: the task in question
+ * @clone_flags: CLONE_* flags for @child
+ * @new_rgrp_cset: *@new_rgrp_csetp from cgroup_can_fork()
*
* Adds the task to the list running through its css_set if necessary and
* call the subsystem fork() callbacks. Has to be after the task is
@@ -5760,7 +5768,8 @@ void cgroup_cancel_fork(struct task_struct *child)
* cgroup_task_iter_start() - to guarantee that the new task ends up on its
* list.
*/
-void cgroup_post_fork(struct task_struct *child)
+void cgroup_post_fork(struct task_struct *child, unsigned long clone_flags,
+ struct css_set *new_rgrp_cset)
{
struct cgroup_subsys *ss;
int i;
diff --git a/kernel/fork.c b/kernel/fork.c
index fd826de..812d477 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1249,6 +1249,7 @@ static struct task_struct *copy_process(unsigned long
clone_flags,
{
int retval;
struct task_struct *p;
+ struct css_set *new_rgrp_cset;
if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
return ERR_PTR(-EINVAL);
@@ -1525,7 +1526,7 @@ static struct task_struct *copy_process(unsigned long
clone_flags,
* between here and cgroup_post_fork() if an organisation operation is
in
* progress.
*/
- retval = cgroup_can_fork(p);
+ retval = cgroup_can_fork(p, clone_flags, &new_rgrp_cset);
if (retval)
goto bad_fork_free_pid;
@@ -1607,7 +1608,7 @@ static struct task_struct *copy_process(unsigned long
clone_flags,
write_unlock_irq(&tasklist_lock);
proc_fork_connector(p);
- cgroup_post_fork(p);
+ cgroup_post_fork(p, clone_flags, new_rgrp_cset);
threadgroup_change_end(current);
perf_event_fork(p);
@@ -1617,7 +1618,7 @@ static struct task_struct *copy_process(unsigned long
clone_flags,
return p;
bad_fork_cancel_cgroup:
- cgroup_cancel_fork(p);
+ cgroup_cancel_fork(p, clone_flags, new_rgrp_cset);
bad_fork_free_pid:
if (pid != &init_struct_pid)
free_pid(pid);
--
2.5.0
