sched: Allow for positional tg_tree walks (8277434e) · Commits · 戴 / test

kernel/sched.c

+37 −13

Original line number	Diff line number	Diff line
		@@ -1591,20 +1591,23 @@ static inline void dec_cpu_load(struct rq *rq, unsigned long load)
		typedef int (tg_visitor)(struct task_group , void *);

		/*
		* Iterate the full tree, calling @down when first entering a node and @up when
		* leaving it for the final time.
		* Iterate task_group tree rooted at *from, calling @down when first entering a
		* node and @up when leaving it for the final time.
		*
		* Caller must hold rcu_lock or sufficient equivalent.
		*/
		static int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
		static int walk_tg_tree_from(struct task_group *from,
		tg_visitor down, tg_visitor up, void *data)
		{
		struct task_group parent, child;
		int ret;

		rcu_read_lock();
		parent = &root_task_group;
		parent = from;

		down:
		ret = (*down)(parent, data);
		if (ret)
		goto out_unlock;
		goto out;
		list_for_each_entry_rcu(child, &parent->children, siblings) {
		parent = child;
		goto down;
		@@ -1613,19 +1616,29 @@ up:
		continue;
		}
		ret = (*up)(parent, data);
		if (ret)
		goto out_unlock;
		if (ret \|\| parent == from)
		goto out;

		child = parent;
		parent = parent->parent;
		if (parent)
		goto up;
		out_unlock:
		rcu_read_unlock();

		out:
		return ret;
		}

		/*
		* Iterate the full tree, calling @down when first entering a node and @up when
		* leaving it for the final time.
		*
		* Caller must hold rcu_lock or sufficient equivalent.
		*/

		static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
		{
		return walk_tg_tree_from(&root_task_group, down, up, data);
		}

		static int tg_nop(struct task_group tg, void data)
		{
		return 0;
		@@ -8870,13 +8883,19 @@ static int tg_rt_schedulable(struct task_group tg, void data)

		static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
		{
		int ret;

		struct rt_schedulable_data data = {
		.tg = tg,
		.rt_period = period,
		.rt_runtime = runtime,
		};

		return walk_tg_tree(tg_rt_schedulable, tg_nop, &data);
		rcu_read_lock();
		ret = walk_tg_tree(tg_rt_schedulable, tg_nop, &data);
		rcu_read_unlock();

		return ret;
		}

		static int tg_set_rt_bandwidth(struct task_group *tg,
		@@ -9333,6 +9352,7 @@ static int tg_cfs_schedulable_down(struct task_group tg, void data)

		static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
		{
		int ret;
		struct cfs_schedulable_data data = {
		.tg = tg,
		.period = period,
		@@ -9344,7 +9364,11 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
		do_div(data.quota, NSEC_PER_USEC);
		}

		return walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data);
		rcu_read_lock();
		ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data);
		rcu_read_unlock();

		return ret;
		}
		#endif /* CONFIG_CFS_BANDWIDTH */
		#endif /* CONFIG_FAIR_GROUP_SCHED */

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