pandora: update defconfig
[pandora-kernel.git] / block / cfq-iosched.c
index 5f127cf..5ff4f48 100644 (file)
@@ -55,6 +55,7 @@ static const int cfq_hist_divisor = 4;
 #define RQ_CIC(rq)             \
        ((struct cfq_io_context *) (rq)->elevator_private)
 #define RQ_CFQQ(rq)            (struct cfq_queue *) ((rq)->elevator_private2)
+#define RQ_CFQG(rq)            (struct cfq_group *) ((rq)->elevator_private3)
 
 static struct kmem_cache *cfq_pool;
 static struct kmem_cache *cfq_ioc_pool;
@@ -63,6 +64,9 @@ static DEFINE_PER_CPU(unsigned long, cfq_ioc_count);
 static struct completion *ioc_gone;
 static DEFINE_SPINLOCK(ioc_gone_lock);
 
+static DEFINE_SPINLOCK(cic_index_lock);
+static DEFINE_IDA(cic_index_ida);
+
 #define CFQ_PRIO_LISTS         IOPRIO_BE_NR
 #define cfq_class_idle(cfqq)   ((cfqq)->ioprio_class == IOPRIO_CLASS_IDLE)
 #define cfq_class_rt(cfqq)     ((cfqq)->ioprio_class == IOPRIO_CLASS_RT)
@@ -143,8 +147,6 @@ struct cfq_queue {
        struct cfq_queue *new_cfqq;
        struct cfq_group *cfqg;
        struct cfq_group *orig_cfqg;
-       /* Sectors dispatched in current dispatch round */
-       unsigned long nr_sectors;
 };
 
 /*
@@ -272,6 +274,7 @@ struct cfq_data {
        unsigned int cfq_latency;
        unsigned int cfq_group_isolation;
 
+       unsigned int cic_index;
        struct list_head cic_list;
 
        /*
@@ -346,7 +349,7 @@ CFQ_CFQQ_FNS(deep);
 CFQ_CFQQ_FNS(wait_busy);
 #undef CFQ_CFQQ_FNS
 
-#ifdef CONFIG_DEBUG_CFQ_IOSCHED
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
 #define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
        blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \
                        cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \
@@ -431,6 +434,24 @@ static inline void cic_set_cfqq(struct cfq_io_context *cic,
        cic->cfqq[is_sync] = cfqq;
 }
 
+#define CIC_DEAD_KEY   1ul
+#define CIC_DEAD_INDEX_SHIFT   1
+
+static inline void *cfqd_dead_key(struct cfq_data *cfqd)
+{
+       return (void *)(cfqd->cic_index << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);
+}
+
+static inline struct cfq_data *cic_to_cfqd(struct cfq_io_context *cic)
+{
+       struct cfq_data *cfqd = cic->key;
+
+       if (unlikely((unsigned long) cfqd & CIC_DEAD_KEY))
+               return NULL;
+
+       return cfqd;
+}
+
 /*
  * We regard a request as SYNC, if it's either a read or has the SYNC bit
  * set (in which case it could also be direct WRITE).
@@ -858,7 +879,7 @@ cfq_group_service_tree_del(struct cfq_data *cfqd, struct cfq_group *cfqg)
        if (!RB_EMPTY_NODE(&cfqg->rb_node))
                cfq_rb_erase(&cfqg->rb_node, st);
        cfqg->saved_workload_slice = 0;
-       blkiocg_update_blkio_group_dequeue_stats(&cfqg->blkg, 1);
+       blkiocg_update_dequeue_stats(&cfqg->blkg, 1);
 }
 
 static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
@@ -884,8 +905,7 @@ static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq)
                        slice_used = cfqq->allocated_slice;
        }
 
-       cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u sect=%lu", slice_used,
-                               cfqq->nr_sectors);
+       cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u", slice_used);
        return slice_used;
 }
 
@@ -919,8 +939,8 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
 
        cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
                                        st->min_vdisktime);
-       blkiocg_update_blkio_group_stats(&cfqg->blkg, used_sl,
-                                               cfqq->nr_sectors);
+       blkiocg_update_timeslice_used(&cfqg->blkg, used_sl);
+       blkiocg_set_start_empty_time(&cfqg->blkg);
 }
 
 #ifdef CONFIG_CFQ_GROUP_IOSCHED
@@ -961,7 +981,6 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
        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);
@@ -978,6 +997,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
        sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
        blkiocg_add_blkio_group(blkcg, &cfqg->blkg, (void *)cfqd,
                                        MKDEV(major, minor));
+       cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev);
 
        /* Add group on cfqd list */
        hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
@@ -1004,6 +1024,12 @@ static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, int create)
        return cfqg;
 }
 
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+       atomic_inc(&cfqg->ref);
+       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 */
@@ -1087,6 +1113,12 @@ static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, int create)
 {
        return &cfqd->root_group;
 }
+
+static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
+{
+       return cfqg;
+}
+
 static inline void
 cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) {
        cfqq->cfqg = cfqg;
@@ -1389,7 +1421,12 @@ static void cfq_reposition_rq_rb(struct cfq_queue *cfqq, struct request *rq)
 {
        elv_rb_del(&cfqq->sort_list, rq);
        cfqq->queued[rq_is_sync(rq)]--;
+       blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+                                               rq_is_sync(rq));
        cfq_add_rq_rb(rq);
+       blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+                       &cfqq->cfqd->serving_group->blkg, rq_data_dir(rq),
+                       rq_is_sync(rq));
 }
 
 static struct request *
@@ -1445,6 +1482,8 @@ static void cfq_remove_request(struct request *rq)
        cfq_del_rq_rb(rq);
 
        cfqq->cfqd->rq_queued--;
+       blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(rq),
+                                               rq_is_sync(rq));
        if (rq_is_meta(rq)) {
                WARN_ON(!cfqq->meta_pending);
                cfqq->meta_pending--;
@@ -1476,6 +1515,13 @@ static void cfq_merged_request(struct request_queue *q, struct request *req,
        }
 }
 
+static void cfq_bio_merged(struct request_queue *q, struct request *req,
+                               struct bio *bio)
+{
+       blkiocg_update_io_merged_stats(&(RQ_CFQG(req))->blkg, bio_data_dir(bio),
+                                       cfq_bio_sync(bio));
+}
+
 static void
 cfq_merged_requests(struct request_queue *q, struct request *rq,
                    struct request *next)
@@ -1493,6 +1539,8 @@ cfq_merged_requests(struct request_queue *q, struct request *rq,
        if (cfqq->next_rq == next)
                cfqq->next_rq = rq;
        cfq_remove_request(next);
+       blkiocg_update_io_merged_stats(&(RQ_CFQG(rq))->blkg, rq_data_dir(next),
+                                       rq_is_sync(next));
 }
 
 static int cfq_allow_merge(struct request_queue *q, struct request *rq,
@@ -1520,18 +1568,24 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
        return cfqq == RQ_CFQQ(rq);
 }
 
+static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+       del_timer(&cfqd->idle_slice_timer);
+       blkiocg_update_idle_time_stats(&cfqq->cfqg->blkg);
+}
+
 static void __cfq_set_active_queue(struct cfq_data *cfqd,
                                   struct cfq_queue *cfqq)
 {
        if (cfqq) {
                cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
                                cfqd->serving_prio, cfqd->serving_type);
+               blkiocg_update_avg_queue_size_stats(&cfqq->cfqg->blkg);
                cfqq->slice_start = 0;
                cfqq->dispatch_start = jiffies;
                cfqq->allocated_slice = 0;
                cfqq->slice_end = 0;
                cfqq->slice_dispatch = 0;
-               cfqq->nr_sectors = 0;
 
                cfq_clear_cfqq_wait_request(cfqq);
                cfq_clear_cfqq_must_dispatch(cfqq);
@@ -1539,7 +1593,7 @@ static void __cfq_set_active_queue(struct cfq_data *cfqd,
                cfq_clear_cfqq_fifo_expire(cfqq);
                cfq_mark_cfqq_slice_new(cfqq);
 
-               del_timer(&cfqd->idle_slice_timer);
+               cfq_del_timer(cfqd, cfqq);
        }
 
        cfqd->active_queue = cfqq;
@@ -1555,7 +1609,7 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
        cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out);
 
        if (cfq_cfqq_wait_request(cfqq))
-               del_timer(&cfqd->idle_slice_timer);
+               cfq_del_timer(cfqd, cfqq);
 
        cfq_clear_cfqq_wait_request(cfqq);
        cfq_clear_cfqq_wait_busy(cfqq);
@@ -1857,6 +1911,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
        sl = cfqd->cfq_slice_idle;
 
        mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
+       blkiocg_update_set_idle_time_stats(&cfqq->cfqg->blkg);
        cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu", sl);
 }
 
@@ -1876,7 +1931,8 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
        elv_dispatch_sort(q, rq);
 
        cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
-       cfqq->nr_sectors += blk_rq_sectors(rq);
+       blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
+                                       rq_data_dir(rq), rq_is_sync(rq));
 }
 
 /*
@@ -2476,11 +2532,12 @@ static void cfq_cic_free(struct cfq_io_context *cic)
 static void cic_free_func(struct io_context *ioc, struct cfq_io_context *cic)
 {
        unsigned long flags;
+       unsigned long dead_key = (unsigned long) cic->key;
 
-       BUG_ON(!cic->dead_key);
+       BUG_ON(!(dead_key & CIC_DEAD_KEY));
 
        spin_lock_irqsave(&ioc->lock, flags);
-       radix_tree_delete(&ioc->radix_root, cic->dead_key);
+       radix_tree_delete(&ioc->radix_root, dead_key >> CIC_DEAD_INDEX_SHIFT);
        hlist_del_rcu(&cic->cic_list);
        spin_unlock_irqrestore(&ioc->lock, flags);
 
@@ -2503,15 +2560,10 @@ static void cfq_free_io_context(struct io_context *ioc)
        __call_for_each_cic(ioc, cic_free_func);
 }
 
-static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+static void cfq_put_cooperator(struct cfq_queue *cfqq)
 {
        struct cfq_queue *__cfqq, *next;
 
-       if (unlikely(cfqq == cfqd->active_queue)) {
-               __cfq_slice_expired(cfqd, cfqq, 0);
-               cfq_schedule_dispatch(cfqd);
-       }
-
        /*
         * If this queue was scheduled to merge with another queue, be
         * sure to drop the reference taken on that queue (and others in
@@ -2527,6 +2579,16 @@ static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
                cfq_put_queue(__cfqq);
                __cfqq = next;
        }
+}
+
+static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+       if (unlikely(cfqq == cfqd->active_queue)) {
+               __cfq_slice_expired(cfqd, cfqq, 0);
+               cfq_schedule_dispatch(cfqd);
+       }
+
+       cfq_put_cooperator(cfqq);
 
        cfq_put_queue(cfqq);
 }
@@ -2539,11 +2601,10 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
        list_del_init(&cic->queue_list);
 
        /*
-        * Make sure key == NULL is seen for dead queues
+        * Make sure dead mark is seen for dead queues
         */
        smp_wmb();
-       cic->dead_key = (unsigned long) cic->key;
-       cic->key = NULL;
+       cic->key = cfqd_dead_key(cfqd);
 
        if (ioc->ioc_data == cic)
                rcu_assign_pointer(ioc->ioc_data, NULL);
@@ -2562,7 +2623,7 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
 static void cfq_exit_single_io_context(struct io_context *ioc,
                                       struct cfq_io_context *cic)
 {
-       struct cfq_data *cfqd = cic->key;
+       struct cfq_data *cfqd = cic_to_cfqd(cic);
 
        if (cfqd) {
                struct request_queue *q = cfqd->queue;
@@ -2575,7 +2636,7 @@ static void cfq_exit_single_io_context(struct io_context *ioc,
                 * race between exiting task and queue
                 */
                smp_read_barrier_depends();
-               if (cic->key)
+               if (cic->key == cfqd)
                        __cfq_exit_single_io_context(cfqd, cic);
 
                spin_unlock_irqrestore(q->queue_lock, flags);
@@ -2655,7 +2716,7 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc)
 
 static void changed_ioprio(struct io_context *ioc, struct cfq_io_context *cic)
 {
-       struct cfq_data *cfqd = cic->key;
+       struct cfq_data *cfqd = cic_to_cfqd(cic);
        struct cfq_queue *cfqq;
        unsigned long flags;
 
@@ -2712,7 +2773,7 @@ static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
 static void changed_cgroup(struct io_context *ioc, struct cfq_io_context *cic)
 {
        struct cfq_queue *sync_cfqq = cic_to_cfqq(cic, 1);
-       struct cfq_data *cfqd = cic->key;
+       struct cfq_data *cfqd = cic_to_cfqd(cic);
        unsigned long flags;
        struct request_queue *q;
 
@@ -2849,12 +2910,13 @@ cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc,
        unsigned long flags;
 
        WARN_ON(!list_empty(&cic->queue_list));
+       BUG_ON(cic->key != cfqd_dead_key(cfqd));
 
        spin_lock_irqsave(&ioc->lock, flags);
 
        BUG_ON(ioc->ioc_data == cic);
 
-       radix_tree_delete(&ioc->radix_root, (unsigned long) cfqd);
+       radix_tree_delete(&ioc->radix_root, cfqd->cic_index);
        hlist_del_rcu(&cic->cic_list);
        spin_unlock_irqrestore(&ioc->lock, flags);
 
@@ -2866,7 +2928,6 @@ cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc)
 {
        struct cfq_io_context *cic;
        unsigned long flags;
-       void *k;
 
        if (unlikely(!ioc))
                return NULL;
@@ -2883,13 +2944,11 @@ cfq_cic_lookup(struct cfq_data *cfqd, struct io_context *ioc)
        }
 
        do {
-               cic = radix_tree_lookup(&ioc->radix_root, (unsigned long) cfqd);
+               cic = radix_tree_lookup(&ioc->radix_root, cfqd->cic_index);
                rcu_read_unlock();
                if (!cic)
                        break;
-               /* ->key must be copied to avoid race with cfq_exit_queue() */
-               k = cic->key;
-               if (unlikely(!k)) {
+               if (unlikely(cic->key != cfqd)) {
                        cfq_drop_dead_cic(cfqd, ioc, cic);
                        rcu_read_lock();
                        continue;
@@ -2922,7 +2981,7 @@ static int cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc,
 
                spin_lock_irqsave(&ioc->lock, flags);
                ret = radix_tree_insert(&ioc->radix_root,
-                                               (unsigned long) cfqd, cic);
+                                               cfqd->cic_index, cic);
                if (!ret)
                        hlist_add_head_rcu(&cic->cic_list, &ioc->cic_list);
                spin_unlock_irqrestore(&ioc->lock, flags);
@@ -3185,11 +3244,14 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
                if (cfq_cfqq_wait_request(cfqq)) {
                        if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE ||
                            cfqd->busy_queues > 1) {
-                               del_timer(&cfqd->idle_slice_timer);
+                               cfq_del_timer(cfqd, cfqq);
                                cfq_clear_cfqq_wait_request(cfqq);
                                __blk_run_queue(cfqd->queue);
-                       } else
+                       } else {
+                               blkiocg_update_idle_time_stats(
+                                               &cfqq->cfqg->blkg);
                                cfq_mark_cfqq_must_dispatch(cfqq);
+                       }
                }
        } else if (cfq_should_preempt(cfqd, cfqq, rq)) {
                /*
@@ -3214,7 +3276,9 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
        rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
        list_add_tail(&rq->queuelist, &cfqq->fifo);
        cfq_add_rq_rb(rq);
-
+       blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
+                       &cfqd->serving_group->blkg, rq_data_dir(rq),
+                       rq_is_sync(rq));
        cfq_rq_enqueued(cfqd, cfqq, rq);
 }
 
@@ -3300,6 +3364,9 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
        WARN_ON(!cfqq->dispatched);
        cfqd->rq_in_driver--;
        cfqq->dispatched--;
+       blkiocg_update_completion_stats(&cfqq->cfqg->blkg, rq_start_time_ns(rq),
+                       rq_io_start_time_ns(rq), rq_data_dir(rq),
+                       rq_is_sync(rq));
 
        cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
 
@@ -3440,6 +3507,10 @@ static void cfq_put_request(struct request *rq)
                rq->elevator_private = NULL;
                rq->elevator_private2 = NULL;
 
+               /* Put down rq reference on cfqg */
+               cfq_put_cfqg(RQ_CFQG(rq));
+               rq->elevator_private3 = NULL;
+
                cfq_put_queue(cfqq);
        }
 }
@@ -3470,6 +3541,9 @@ split_cfqq(struct cfq_io_context *cic, struct cfq_queue *cfqq)
        }
 
        cic_set_cfqq(cic, NULL, 1);
+
+       cfq_put_cooperator(cfqq);
+
        cfq_put_queue(cfqq);
        return NULL;
 }
@@ -3528,6 +3602,7 @@ new_queue:
 
        rq->elevator_private = cic;
        rq->elevator_private2 = cfqq;
+       rq->elevator_private3 = cfq_ref_get_cfqg(cfqq->cfqg);
        return 0;
 
 queue_fail:
@@ -3661,10 +3736,32 @@ static void cfq_exit_queue(struct elevator_queue *e)
 
        cfq_shutdown_timer_wq(cfqd);
 
+       spin_lock(&cic_index_lock);
+       ida_remove(&cic_index_ida, cfqd->cic_index);
+       spin_unlock(&cic_index_lock);
+
        /* Wait for cfqg->blkg->key accessors to exit their grace periods. */
        call_rcu(&cfqd->rcu, cfq_cfqd_free);
 }
 
+static int cfq_alloc_cic_index(void)
+{
+       int index, error;
+
+       do {
+               if (!ida_pre_get(&cic_index_ida, GFP_KERNEL))
+                       return -ENOMEM;
+
+               spin_lock(&cic_index_lock);
+               error = ida_get_new(&cic_index_ida, &index);
+               spin_unlock(&cic_index_lock);
+               if (error && error != -EAGAIN)
+                       return error;
+       } while (error);
+
+       return index;
+}
+
 static void *cfq_init_queue(struct request_queue *q)
 {
        struct cfq_data *cfqd;
@@ -3672,10 +3769,16 @@ static void *cfq_init_queue(struct request_queue *q)
        struct cfq_group *cfqg;
        struct cfq_rb_root *st;
 
+       i = cfq_alloc_cic_index();
+       if (i < 0)
+               return NULL;
+
        cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
        if (!cfqd)
                return NULL;
 
+       cfqd->cic_index = i;
+
        /* Init root service tree */
        cfqd->grp_service_tree = CFQ_RB_ROOT;
 
@@ -3743,7 +3846,6 @@ static void *cfq_init_queue(struct request_queue *q)
         * second, in order to have larger depth for async operations.
         */
        cfqd->last_delayed_sync = jiffies - HZ;
-       INIT_RCU_HEAD(&cfqd->rcu);
        return cfqd;
 }
 
@@ -3872,6 +3974,7 @@ static struct elevator_type iosched_cfq = {
                .elevator_merged_fn =           cfq_merged_request,
                .elevator_merge_req_fn =        cfq_merged_requests,
                .elevator_allow_merge_fn =      cfq_allow_merge,
+               .elevator_bio_merged_fn =       cfq_bio_merged,
                .elevator_dispatch_fn =         cfq_dispatch_requests,
                .elevator_add_req_fn =          cfq_insert_request,
                .elevator_activate_req_fn =     cfq_activate_request,
@@ -3937,6 +4040,7 @@ static void __exit cfq_exit(void)
         */
        if (elv_ioc_count_read(cfq_ioc_count))
                wait_for_completion(&all_gone);
+       ida_destroy(&cic_index_ida);
        cfq_slab_kill();
 }