sched: Skip autogroup when looking for all rt sched groups (1c09ab0d) · Commits · 戴 / test

Since commit ("sched: Fix rt_rq runtime leakage bug") 'cat /proc/sched_debug' will print data of root_task_group.rt_rq multiple times. This is because autogroup does not have its own rt group, instead rt group of autogroup is linked to root_task_group. So skip it when we are looking for all rt sched groups, and it will also save some noop operation against root_task_group when __disable_runtime()/__enable_runtime(). -v2: Based on Cheng Xu's idea which uses less code. Signed-off-by:

Yong Zhang <yong.zhang0@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Cheng Xu <chengxu@linux.vnet.ibm.com> Signed-off-by:

Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/BANLkTi=87P3RoTF_UEtamNfc_XGxQXE__Q@mail.gmail.com Signed-off-by:

Ingo Molnar <mingo@elte.hu>

kernel/sched_autogroup.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,7 @@ struct autogroup {
		int nice;
		};

		static inline bool task_group_is_autogroup(struct task_group *tg);
		static inline struct task_group *
		autogroup_task_group(struct task_struct p, struct task_group tg);

kernel/sched_rt.c

+17 −5

Original line number	Diff line number	Diff line
		@@ -185,11 +185,23 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq)

		typedef struct task_group *rt_rq_iter_t;

		static inline struct task_group next_task_group(struct task_group tg)
		{
		do {
		tg = list_entry_rcu(tg->list.next,
		typeof(struct task_group), list);
		} while (&tg->list != &task_groups && task_group_is_autogroup(tg));

		if (&tg->list == &task_groups)
		tg = NULL;

		return tg;
		}

		#define for_each_rt_rq(rt_rq, iter, rq) \
		for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \
		(&iter->list != &task_groups) && \
		(rt_rq = iter->rt_rq[cpu_of(rq)]); \
		iter = list_entry_rcu(iter->list.next, typeof(*iter), list))
		for (iter = container_of(&task_groups, typeof(*iter), list); \
		(iter = next_task_group(iter)) && \
		(rt_rq = iter->rt_rq[cpu_of(rq)]);)

		static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
		{

Admin message