On Thu, 2011-02-03 at 00:32 +0530, Balbir Singh wrote:
> > No, just fixed. The callback as it exists isn't useful and leads to
> > hacks like the above.
---
Subject: cgroup: Fix cgroup_subsys::exit callback
From: Peter Zijlstra <a.p.zijls...@chello.nl>
Date: Mon Feb 07 17:02:20 CET 2011
Make the ::exit method act like ::attach, it is after all very nearly
the same thing.
Signed-off-by: Peter Zijlstra <a.p.zijls...@chello.nl>
LKML-Reference: <new-submission>
---
Index: linux-2.6/include/linux/cgroup.h
===================================================================
--- linux-2.6.orig/include/linux/cgroup.h
+++ linux-2.6/include/linux/cgroup.h
@@ -474,7 +474,8 @@ struct cgroup_subsys {
struct cgroup *old_cgrp, struct task_struct *tsk,
bool threadgroup);
void (*fork)(struct cgroup_subsys *ss, struct task_struct *task);
- void (*exit)(struct cgroup_subsys *ss, struct task_struct *task);
+ void (*exit)(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup *old_cgrp, struct task_struct *task);
int (*populate)(struct cgroup_subsys *ss,
struct cgroup *cgrp);
void (*post_clone)(struct cgroup_subsys *ss, struct cgroup *cgrp);
Index: linux-2.6/kernel/cgroup.c
===================================================================
--- linux-2.6.orig/kernel/cgroup.c
+++ linux-2.6/kernel/cgroup.c
@@ -4230,20 +4230,10 @@ void cgroup_post_fork(struct task_struct
*/
void cgroup_exit(struct task_struct *tsk, int run_callbacks)
{
- int i;
struct css_set *cg;
+ int i;
- if (run_callbacks && need_forkexit_callback) {
- /*
- * modular subsystems can't use callbacks, so no need to lock
- * the subsys array
- */
- for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
- struct cgroup_subsys *ss = subsys[i];
- if (ss->exit)
- ss->exit(ss, tsk);
- }
- }
+ mutex_lock(&cgroup_mutex);
/*
* Unlink from the css_set task list if necessary.
@@ -4262,6 +4252,25 @@ void cgroup_exit(struct task_struct *tsk
cg = tsk->cgroups;
tsk->cgroups = &init_css_set;
task_unlock(tsk);
+
+ if (run_callbacks && need_forkexit_callback) {
+ /*
+ * modular subsystems can't use callbacks, so no need to lock
+ * the subsys array
+ */
+ for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+ struct cgroup_subsys *ss = subsys[i];
+ if (ss->exit) {
+ struct cgroup *old_cgrp =
+
rcu_dereference_raw(cg->subsys[i])->cgroup;
+ struct cgroup *cgrp = task_cgroup(tsk, i);
+ ss->exit(ss, cgrp, old_cgrp, tsk);
+ }
+ }
+ }
+
+ mutex_unlock(&cgroup_mutex);
+
if (cg)
put_css_set_taskexit(cg);
}
Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c
+++ linux-2.6/kernel/sched.c
@@ -606,9 +606,6 @@ static inline struct task_group *task_gr
struct task_group *tg;
struct cgroup_subsys_state *css;
- if (p->flags & PF_EXITING)
- return &root_task_group;
-
css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
lockdep_is_held(&task_rq(p)->lock));
tg = container_of(css, struct task_group, css);
@@ -9081,7 +9078,8 @@ cpu_cgroup_attach(struct cgroup_subsys *
}
static void
-cpu_cgroup_exit(struct cgroup_subsys *ss, struct task_struct *task)
+cpu_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup *old_cgrp, struct task_struct *task)
{
/*
* cgroup_exit() is called in the copy_process() failure path.
------------------------------------------------------------------------------
The modern datacenter depends on network connectivity to access resources
and provide services. The best practices for maximizing a physical server's
connectivity to a physical network are well understood - see how these
rules translate into the virtual world?
http://p.sf.net/sfu/oracle-sfdevnlfb
_______________________________________________
perfmon2-devel mailing list
perfmon2-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
