linux-master/block/blk-stat.c

53 	struct blk_stat_callback *cb;
65 	list_for_each_entry_rcu(cb, &q->stats->callbacks, list) {
66 		if (!blk_stat_is_active(cb))
69 		bucket = cb->bucket_fn(rq);
73 		stat = &per_cpu_ptr(cb->cpu_stat, cpu)[bucket];
82 	struct blk_stat_callback *cb = from_timer(cb, t, timer);
86 	for (bucket = 0; bucket < cb->buckets; bucket++)
87 		blk_rq_stat_init(&cb->stat[bucket]);
92 		cpu_stat = per_cpu_ptr(cb->cpu_stat, cpu);
93 		for (bucket = 0; bucket < cb->buckets; bucket++) {
94 			blk_rq_stat_sum(&cb->stat[bucket], &cpu_stat[bucket]);
99 	cb->timer_fn(cb);
107 	struct blk_stat_callback *cb;
109 	cb = kmalloc(sizeof(*cb), GFP_KERNEL);
110 	if (!cb)
113 	cb->stat = kmalloc_array(buckets, sizeof(struct blk_rq_stat),
115 	if (!cb->stat) {
116 		kfree(cb);
119 	cb->cpu_stat = __alloc_percpu(buckets * sizeof(struct blk_rq_stat),
121 	if (!cb->cpu_stat) {
122 		kfree(cb->stat);
123 		kfree(cb);
127 	cb->timer_fn = timer_fn;
128 	cb->bucket_fn = bucket_fn;
129 	cb->data = data;
130 	cb->buckets = buckets;
131 	timer_setup(&cb->timer, blk_stat_timer_fn, 0);
133 	return cb;
137 			   struct blk_stat_callback *cb)
146 		cpu_stat = per_cpu_ptr(cb->cpu_stat, cpu);
147 		for (bucket = 0; bucket < cb->buckets; bucket++)
152 	list_add_tail_rcu(&cb->list, &q->stats->callbacks);
158 			      struct blk_stat_callback *cb)
163 	list_del_rcu(&cb->list);
168 	del_timer_sync(&cb->timer);
173 	struct blk_stat_callback *cb;
175 	cb = container_of(head, struct blk_stat_callback, rcu);
176 	free_percpu(cb->cpu_stat);
177 	kfree(cb->stat);
178 	kfree(cb);
181 void blk_stat_free_callback(struct blk_stat_callback *cb)
183 	if (cb)
184 		call_rcu(&cb->rcu, blk_stat_free_callback_rcu);