Unverified Commit 29094e84 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!1408 Replace the hulk patch with the lts patch 

Merge Pull Request from: @ci-robot 
 
PR sync from: Gaosheng Cui <cuigaosheng1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/KDI6HM6ETZD4MQLPN2PXX7TI3XO7ZJC5/ 
Replace the hulk patch with the lts patch, thanks!

Gaosheng Cui (1):
  Revert "cgroup: Stop task iteration when rebinding subsystem"

Xiu Jianfeng (1):
  cgroup: Do not corrupt task iteration when rebinding subsystem


-- 
2.30.0
 
https://gitee.com/openeuler/kernel/issues/I7AZ85 
 
Link:https://gitee.com/openeuler/kernel/pulls/1408

 

Reviewed-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 0a7be323 d09e69cd

include/linux/cgroup.h

+0 −1
Original line number Diff line number Diff line
@@ -47,7 +47,6 @@ struct kernel_clone_args; 


/* internal flags */

#define CSS_TASK_ITER_SKIPPED		(1U << 16)

#define CSS_TASK_ITER_STOPPED		(1U << 17)



/* a css_task_iter should be treated as an opaque object */

struct css_task_iter {

kernel/cgroup/cgroup.c

+16 −34
Original line number Diff line number Diff line
@@ -215,8 +215,6 @@ static int cgroup_apply_control(struct cgroup *cgrp); 
static void cgroup_finalize_control(struct cgroup *cgrp, int ret);

static void css_task_iter_skip(struct css_task_iter *it,

			       struct task_struct *task);

static void css_task_iter_stop(struct css_task_iter *it,

			       struct cgroup_subsys *ss);

static int cgroup_destroy_locked(struct cgroup *cgrp);

static struct cgroup_subsys_state *css_create(struct cgroup *cgrp,

					      struct cgroup_subsys *ss);
@@ -857,19 +855,6 @@ static void css_set_skip_task_iters(struct css_set *cset, 
		css_task_iter_skip(it, task);

}



/*

 * @cset is moving to other list, it's not safe to continue the iteration,

 * because the cset_head of css_task_iter which is from the old list can

 * not be used as the stop condition of iteration.

 */

static void css_set_stop_iters(struct css_set *cset, struct cgroup_subsys *ss)

{

	struct css_task_iter *it, *pos;



	list_for_each_entry_safe(it, pos, &cset->task_iters, iters_node)

		css_task_iter_stop(it, ss);

}



/**

 * css_set_move_task - move a task from one css_set to another

 * @task: task being moved
@@ -1728,7 +1713,7 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask) 
{

	struct cgroup *dcgrp = &dst_root->cgrp;

	struct cgroup_subsys *ss;

	int ssid, i, ret;

	int ssid, ret;

	u16 dfl_disable_ss_mask = 0;



	lockdep_assert_held(&cgroup_mutex);
@@ -1772,7 +1757,8 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask) 
		struct cgroup_root *src_root = ss->root;

		struct cgroup *scgrp = &src_root->cgrp;

		struct cgroup_subsys_state *css = cgroup_css(scgrp, ss);

		struct css_set *cset;

		struct css_set *cset, *cset_pos;

		struct css_task_iter *it;



		WARN_ON(!css || cgroup_css(dcgrp, ss));
@@ -1790,10 +1776,21 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask) 
		css->cgroup = dcgrp;



		spin_lock_irq(&css_set_lock);

		hash_for_each(css_set_table, i, cset, hlist) {

			css_set_stop_iters(cset, ss);

		WARN_ON(!list_empty(&dcgrp->e_csets[ss->id]));

		list_for_each_entry_safe(cset, cset_pos, &scgrp->e_csets[ss->id],

					 e_cset_node[ss->id]) {

			list_move_tail(&cset->e_cset_node[ss->id],

				       &dcgrp->e_csets[ss->id]);

			/*

			 * all css_sets of scgrp together in same order to dcgrp,

			 * patch in-flight iterators to preserve correct iteration.

			 * since the iterator is always advanced right away and

			 * finished when it->cset_pos meets it->cset_head, so only

			 * update it->cset_head is enough here.

			 */

			list_for_each_entry(it, &cset->task_iters, iters_node)

				if (it->cset_head == &scgrp->e_csets[ss->id])

					it->cset_head = &dcgrp->e_csets[ss->id];

		}

		spin_unlock_irq(&css_set_lock);
@@ -4723,16 +4720,6 @@ static void css_task_iter_skip(struct css_task_iter *it, 
	}

}



static void css_task_iter_stop(struct css_task_iter *it,

			       struct cgroup_subsys *ss)

{

	lockdep_assert_held(&css_set_lock);



	if (it->ss == ss) {

		it->flags |= CSS_TASK_ITER_STOPPED;

	}

}



static void css_task_iter_advance(struct css_task_iter *it)

{

	struct task_struct *task;
@@ -4836,11 +4823,6 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it) 


	spin_lock_irq(&css_set_lock);



	if (it->flags & CSS_TASK_ITER_STOPPED) {

		spin_unlock_irq(&css_set_lock);

		return NULL;

	}



	/* @it may be half-advanced by skips, finish advancing */

	if (it->flags & CSS_TASK_ITER_SKIPPED)

		css_task_iter_advance(it);