Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fix from Ingo Molnar:
 "This is a revert for a lockup in cgroups-intense workloads - the real
  fixes will come later"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f6544b
This commit is contained in:
Linus Torvalds 2018-12-31 09:54:17 -08:00
commit e3ed513bcf

View File

@ -352,10 +352,9 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
}
}
/* Iterate thr' all leaf cfs_rq's on a runqueue */
#define for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) \
list_for_each_entry_safe(cfs_rq, pos, &rq->leaf_cfs_rq_list, \
leaf_cfs_rq_list)
/* Iterate through all leaf cfs_rq's on a runqueue: */
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
/* Do the two (enqueued) entities belong to the same group ? */
static inline struct cfs_rq *
@ -447,8 +446,8 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
}
#define for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) \
for (cfs_rq = &rq->cfs, pos = NULL; cfs_rq; cfs_rq = pos)
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
static inline struct sched_entity *parent_entity(struct sched_entity *se)
{
@ -7647,27 +7646,10 @@ static inline bool others_have_blocked(struct rq *rq)
#ifdef CONFIG_FAIR_GROUP_SCHED
static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq)
{
if (cfs_rq->load.weight)
return false;
if (cfs_rq->avg.load_sum)
return false;
if (cfs_rq->avg.util_sum)
return false;
if (cfs_rq->avg.runnable_load_sum)
return false;
return true;
}
static void update_blocked_averages(int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct cfs_rq *cfs_rq, *pos;
struct cfs_rq *cfs_rq;
const struct sched_class *curr_class;
struct rq_flags rf;
bool done = true;
@ -7679,7 +7661,7 @@ static void update_blocked_averages(int cpu)
* Iterates the task_group tree in a bottom up fashion, see
* list_add_leaf_cfs_rq() for details.
*/
for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) {
for_each_leaf_cfs_rq(rq, cfs_rq) {
struct sched_entity *se;
/* throttled entities do not contribute to load */
@ -7694,13 +7676,6 @@ static void update_blocked_averages(int cpu)
if (se && !skip_blocked_update(se))
update_load_avg(cfs_rq_of(se), se, 0);
/*
* There can be a lot of idle CPU cgroups. Don't let fully
* decayed cfs_rqs linger on the list.
*/
if (cfs_rq_is_decayed(cfs_rq))
list_del_leaf_cfs_rq(cfs_rq);
/* Don't need periodic decay once load/util_avg are null */
if (cfs_rq_has_blocked(cfs_rq))
done = false;
@ -10570,10 +10545,10 @@ const struct sched_class fair_sched_class = {
#ifdef CONFIG_SCHED_DEBUG
void print_cfs_stats(struct seq_file *m, int cpu)
{
struct cfs_rq *cfs_rq, *pos;
struct cfs_rq *cfs_rq;
rcu_read_lock();
for_each_leaf_cfs_rq_safe(cpu_rq(cpu), cfs_rq, pos)
for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
print_cfs_rq(m, cpu, cfs_rq);
rcu_read_unlock();
}