blkio: Dynamic cfq group creation based on cgroup tasks belongs to (25fb5169) · Commits · 戴 / test

block/cfq-iosched.c

+100 −11

Original line number	Diff line number	Diff line
		@@ -189,6 +189,10 @@ struct cfq_group {
		unsigned long saved_workload_slice;
		enum wl_type_t saved_workload;
		enum wl_prio_t saved_serving_prio;
		struct blkio_group blkg;
		#ifdef CONFIG_CFQ_GROUP_IOSCHED
		struct hlist_node cfqd_node;
		#endif
		};

		/*
		@@ -274,8 +278,13 @@ struct cfq_data {
		struct cfq_queue oom_cfqq;

		unsigned long last_end_sync_rq;

		/* List of cfq groups being managed on this device*/
		struct hlist_head cfqg_list;
		};

		static struct cfq_group cfq_get_next_cfqg(struct cfq_data cfqd);

		static struct cfq_rb_root service_tree_for(struct cfq_group cfqg,
		enum wl_prio_t prio,
		enum wl_type_t type,
		@@ -881,6 +890,89 @@ static void cfq_group_served(struct cfq_data cfqd, struct cfq_group cfqg,
		cfqg->saved_workload_slice = 0;
		}

		#ifdef CONFIG_CFQ_GROUP_IOSCHED
		static inline struct cfq_group cfqg_of_blkg(struct blkio_group blkg)
		{
		if (blkg)
		return container_of(blkg, struct cfq_group, blkg);
		return NULL;
		}

		static struct cfq_group *
		cfq_find_alloc_cfqg(struct cfq_data cfqd, struct cgroup cgroup, int create)
		{
		struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
		struct cfq_group *cfqg = NULL;
		void *key = cfqd;
		int i, j;
		struct cfq_rb_root *st;

		/* Do we need to take this reference */
		if (!css_tryget(&blkcg->css))
		return NULL;;

		cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
		if (cfqg \|\| !create)
		goto done;

		cfqg = kzalloc_node(sizeof(*cfqg), GFP_ATOMIC, cfqd->queue->node);
		if (!cfqg)
		goto done;

		cfqg->weight = blkcg->weight;
		for_each_cfqg_st(cfqg, i, j, st)
		*st = CFQ_RB_ROOT;
		RB_CLEAR_NODE(&cfqg->rb_node);

		/* Add group onto cgroup list */
		blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd);

		/* Add group on cfqd list */
		hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);

		done:
		css_put(&blkcg->css);
		return cfqg;
		}

		/*
		* Search for the cfq group current task belongs to. If create = 1, then also
		* create the cfq group if it does not exist. request_queue lock must be held.
		*/
		static struct cfq_group cfq_get_cfqg(struct cfq_data cfqd, int create)
		{
		struct cgroup *cgroup;
		struct cfq_group *cfqg = NULL;

		rcu_read_lock();
		cgroup = task_cgroup(current, blkio_subsys_id);
		cfqg = cfq_find_alloc_cfqg(cfqd, cgroup, create);
		if (!cfqg && create)
		cfqg = &cfqd->root_group;
		rcu_read_unlock();
		return cfqg;
		}

		static void cfq_link_cfqq_cfqg(struct cfq_queue cfqq, struct cfq_group cfqg)
		{
		/* Currently, all async queues are mapped to root group */
		if (!cfq_cfqq_sync(cfqq))
		cfqg = &cfqq->cfqd->root_group;

		cfqq->cfqg = cfqg;
		}
		#else /* GROUP_IOSCHED */
		static struct cfq_group cfq_get_cfqg(struct cfq_data cfqd, int create)
		{
		return &cfqd->root_group;
		}
		static inline void
		cfq_link_cfqq_cfqg(struct cfq_queue cfqq, struct cfq_group cfqg) {
		cfqq->cfqg = cfqg;
		}

		#endif /* GROUP_IOSCHED */

		/*
		* The cfqd->service_trees holds all pending cfq_queue's that have
		* requests waiting to be processed. It is sorted in the order that
		@@ -1372,7 +1464,7 @@ static struct cfq_queue cfq_get_next_queue(struct cfq_data cfqd)

		static struct cfq_queue cfq_get_next_queue_forced(struct cfq_data cfqd)
		{
		struct cfq_group *cfqg = &cfqd->root_group;
		struct cfq_group *cfqg;
		struct cfq_queue *cfqq;
		int i, j;
		struct cfq_rb_root *st;
		@@ -1380,6 +1472,10 @@ static struct cfq_queue cfq_get_next_queue_forced(struct cfq_data cfqd)
		if (!cfqd->rq_queued)
		return NULL;

		cfqg = cfq_get_next_cfqg(cfqd);
		if (!cfqg)
		return NULL;

		for_each_cfqg_st(cfqg, i, j, st)
		if ((cfqq = cfq_rb_first(st)) != NULL)
		return cfqq;
		@@ -2390,16 +2486,6 @@ static void cfq_init_cfqq(struct cfq_data cfqd, struct cfq_queue cfqq,
		cfqq->pid = pid;
		}

		static void cfq_link_cfqq_cfqg(struct cfq_queue cfqq, struct cfq_group cfqg)
		{
		cfqq->cfqg = cfqg;
		}

		static struct cfq_group cfq_get_cfqg(struct cfq_data cfqd, int create)
		{
		return &cfqd->root_group;
		}

		static struct cfq_queue *
		cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync,
		struct io_context *ioc, gfp_t gfp_mask)
		@@ -3314,6 +3400,9 @@ static void cfq_init_queue(struct request_queue q)
		/* Give preference to root group over other groups */
		cfqg->weight = 2*BLKIO_WEIGHT_DEFAULT;

		#ifdef CONFIG_CFQ_GROUP_IOSCHED
		blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg, (void *)cfqd);
		#endif
		/*
		* Not strictly needed (since RB_ROOT just clears the node and we
		* zeroed cfqd on alloc), but better be safe in case someone decides

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