Hi guys, I investigate
http://lwn.net/Articles/453642/
seems that this really fit my proposal and I can make move this
functionality from core to this css. But, unfortunately, Frederic git is
not available on kernel.org and current Linux kernel doesn't have this
patches. Could you be so kind to provide link to the kernel with this
patches.
On 04/02/2012 02:29 PM, Kirill A. Shutemov wrote:
On Mon, Apr 02, 2012 at 08:22:14AM +0400, Alexander Nikiforov wrote:
I think it should be part of task counter css, not core.
CC list updated.
@@ -4558,6 +4594,22 @@ void cgroup_fork(struct task_struct *child)
child->cgroups = current->cgroups;
get_css_set(child->cgroups);
INIT_LIST_HEAD(&child->cg_list);
+
+ struct cgroupfs_root *root;
+
+ /* send event to the userspace */
+ mutex_lock(&cgroup_mutex);
+ for_each_active_root(root) {
+ struct cgroup *cgrp;
+ struct fe_eventfd_list *ev;
+
+ cgrp = task_cgroup_from_root(child, root);
+
+ list_for_each_entry(ev,&cgrp->fe_notify, list) {
+ eventfd_signal(ev->eventfd, 1);
+ }
+ }
+ mutex_unlock(&cgroup_mutex);
}
How does it affect performance?
/**
@@ -4653,6 +4705,7 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
{
struct css_set *cg;
int i;
+ struct cgroupfs_root *root;
/*
* Unlink from the css_set task list if necessary.
@@ -4666,6 +4719,20 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
write_unlock(&css_set_lock);
}
+ /* send event to the userspace */
+ mutex_lock(&cgroup_mutex);
+ for_each_active_root(root) {
+ struct cgroup *cgrp;
+ struct fe_eventfd_list *ev;
+
+ cgrp = task_cgroup_from_root(tsk, root);
+
+ list_for_each_entry(ev,&cgrp->fe_notify, list) {
+ eventfd_signal(ev->eventfd, 1);
+ }
+ }
+ mutex_unlock(&cgroup_mutex);
+
I think it's racy. You need to notify userspace after reassigning the
task, not before.
/* Reassign the task to the init_css_set. */
task_lock(tsk);
cg = tsk->cgroups;
--
Best regards,
Alex Nikiforov,
Mobile SW, Advanced Software Group,
Moscow R&D center, Samsung Electronics
--
To unsubscribe from this list: send the line "unsubscribe cgroups" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
