1 files changed, 51 insertions, 49 deletions

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 9660ec8d0375..ebaaaa9f57d6 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -284,17 +284,18 @@ static struct throtl_grp *throtl_lookup_create_tg(struct throtl_data *td,
         return tg;
 }
 
-static struct throtl_grp *throtl_rb_first(struct throtl_service_queue *sq)
+static struct throtl_grp *
+throtl_rb_first(struct throtl_service_queue *parent_sq)
 {
         /* Service tree is empty */
-        if (!sq->nr_pending)
+        if (!parent_sq->nr_pending)
                 return NULL;
 
-        if (!sq->first_pending)
-                sq->first_pending = rb_first(&sq->pending_tree);
+        if (!parent_sq->first_pending)
+                parent_sq->first_pending = rb_first(&parent_sq->pending_tree);
 
-        if (sq->first_pending)
-                return rb_entry_tg(sq->first_pending);
+        if (parent_sq->first_pending)
+                return rb_entry_tg(parent_sq->first_pending);
 
         return NULL;
 }
@@ -305,29 +306,30 @@ static void rb_erase_init(struct rb_node *n, struct rb_root *root)
         RB_CLEAR_NODE(n);
 }
 
-static void throtl_rb_erase(struct rb_node *n, struct throtl_service_queue *sq)
+static void throtl_rb_erase(struct rb_node *n,
+                            struct throtl_service_queue *parent_sq)
 {
-        if (sq->first_pending == n)
-                sq->first_pending = NULL;
-        rb_erase_init(n, &sq->pending_tree);
-        --sq->nr_pending;
+        if (parent_sq->first_pending == n)
+                parent_sq->first_pending = NULL;
+        rb_erase_init(n, &parent_sq->pending_tree);
+        --parent_sq->nr_pending;
 }
 
-static void update_min_dispatch_time(struct throtl_service_queue *sq)
+static void update_min_dispatch_time(struct throtl_service_queue *parent_sq)
 {
         struct throtl_grp *tg;
 
-        tg = throtl_rb_first(sq);
+        tg = throtl_rb_first(parent_sq);
         if (!tg)
                 return;
 
-        sq->first_pending_disptime = tg->disptime;
+        parent_sq->first_pending_disptime = tg->disptime;
 }
 
-static void tg_service_queue_add(struct throtl_service_queue *sq,
-                                 struct throtl_grp *tg)
+static void tg_service_queue_add(struct throtl_grp *tg,
+                                 struct throtl_service_queue *parent_sq)
 {
-        struct rb_node **node = &sq->pending_tree.rb_node;
+        struct rb_node **node = &parent_sq->pending_tree.rb_node;
         struct rb_node *parent = NULL;
         struct throtl_grp *__tg;
         unsigned long key = tg->disptime;
@@ -346,39 +348,39 @@ static void tg_service_queue_add(struct throtl_service_queue *sq,
         }
 
         if (left)
-                sq->first_pending = &tg->rb_node;
+                parent_sq->first_pending = &tg->rb_node;
 
         rb_link_node(&tg->rb_node, parent, node);
-        rb_insert_color(&tg->rb_node, &sq->pending_tree);
+        rb_insert_color(&tg->rb_node, &parent_sq->pending_tree);
 }
 
-static void __throtl_enqueue_tg(struct throtl_service_queue *sq,
-                                struct throtl_grp *tg)
+static void __throtl_enqueue_tg(struct throtl_grp *tg,
+                                struct throtl_service_queue *parent_sq)
 {
-        tg_service_queue_add(sq, tg);
+        tg_service_queue_add(tg, parent_sq);
         tg->flags |= THROTL_TG_PENDING;
-        sq->nr_pending++;
+        parent_sq->nr_pending++;
 }
 
-static void throtl_enqueue_tg(struct throtl_service_queue *sq,
-                              struct throtl_grp *tg)
+static void throtl_enqueue_tg(struct throtl_grp *tg,
+                              struct throtl_service_queue *parent_sq)
 {
         if (!(tg->flags & THROTL_TG_PENDING))
-                __throtl_enqueue_tg(sq, tg);
+                __throtl_enqueue_tg(tg, parent_sq);
 }
 
-static void __throtl_dequeue_tg(struct throtl_service_queue *sq,
-                                struct throtl_grp *tg)
+static void __throtl_dequeue_tg(struct throtl_grp *tg,
+                                struct throtl_service_queue *parent_sq)
 {
-        throtl_rb_erase(&tg->rb_node, sq);
+        throtl_rb_erase(&tg->rb_node, parent_sq);
         tg->flags &= ~THROTL_TG_PENDING;
 }
 
-static void throtl_dequeue_tg(struct throtl_service_queue *sq,
-                              struct throtl_grp *tg)
+static void throtl_dequeue_tg(struct throtl_grp *tg,
+                              struct throtl_service_queue *parent_sq)
 {
         if (tg->flags & THROTL_TG_PENDING)
-                __throtl_dequeue_tg(sq, tg);
+                __throtl_dequeue_tg(tg, parent_sq);
 }
 
 /* Call with queue lock held */
@@ -691,8 +693,8 @@ static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio)
         throtl_update_dispatch_stats(tg_to_blkg(tg), bio->bi_size, bio->bi_rw);
 }
 
-static void throtl_add_bio_tg(struct throtl_service_queue *sq,
-                              struct throtl_grp *tg, struct bio *bio)
+static void throtl_add_bio_tg(struct bio *bio, struct throtl_grp *tg,
+                              struct throtl_service_queue *parent_sq)
 {
         bool rw = bio_data_dir(bio);
 
@@ -701,11 +703,11 @@ static void throtl_add_bio_tg(struct throtl_service_queue *sq,
         blkg_get(tg_to_blkg(tg));
         tg->nr_queued[rw]++;
         tg->td->nr_queued[rw]++;
-        throtl_enqueue_tg(sq, tg);
+        throtl_enqueue_tg(tg, parent_sq);
 }
 
-static void tg_update_disptime(struct throtl_service_queue *sq,
-                               struct throtl_grp *tg)
+static void tg_update_disptime(struct throtl_grp *tg,
+                               struct throtl_service_queue *parent_sq)
 {
         unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime;
         struct bio *bio;
@@ -720,9 +722,9 @@ static void tg_update_disptime(struct throtl_service_queue *sq,
         disptime = jiffies + min_wait;
 
         /* Update dispatch time */
-        throtl_dequeue_tg(sq, tg);
+        throtl_dequeue_tg(tg, parent_sq);
         tg->disptime = disptime;
-        throtl_enqueue_tg(sq, tg);
+        throtl_enqueue_tg(tg, parent_sq);
 }
 
 static void tg_dispatch_one_bio(struct throtl_grp *tg, bool rw,
@@ -777,14 +779,14 @@ static int throtl_dispatch_tg(struct throtl_grp *tg, struct bio_list *bl)
         return nr_reads + nr_writes;
 }
 
-static int throtl_select_dispatch(struct throtl_service_queue *sq,
+static int throtl_select_dispatch(struct throtl_service_queue *parent_sq,
                                   struct bio_list *bl)
 {
         unsigned int nr_disp = 0;
         struct throtl_grp *tg;
 
         while (1) {
-                tg = throtl_rb_first(sq);
+                tg = throtl_rb_first(parent_sq);
 
                 if (!tg)
                         break;
@@ -792,12 +794,12 @@ static int throtl_select_dispatch(struct throtl_service_queue *sq,
                 if (time_before(jiffies, tg->disptime))
                         break;
 
-                throtl_dequeue_tg(sq, tg);
+                throtl_dequeue_tg(tg, parent_sq);
 
                 nr_disp += throtl_dispatch_tg(tg, bl);
 
                 if (tg->nr_queued[0] || tg->nr_queued[1])
-                        tg_update_disptime(sq, tg);
+                        tg_update_disptime(tg, parent_sq);
 
                 if (nr_disp >= throtl_quantum)
                         break;
@@ -952,7 +954,7 @@ static int tg_set_conf(struct cgroup *cgrp, struct cftype *cft, const char *buf,
         throtl_start_new_slice(tg, 1);
 
         if (tg->flags & THROTL_TG_PENDING) {
-                tg_update_disptime(&td->service_queue, tg);
+                tg_update_disptime(tg, &td->service_queue);
                 throtl_schedule_next_dispatch(td);
         }
 
@@ -1106,11 +1108,11 @@ queue_bio:
                         tg->nr_queued[READ], tg->nr_queued[WRITE]);
 
         bio_associate_current(bio);
-        throtl_add_bio_tg(&q->td->service_queue, tg, bio);
+        throtl_add_bio_tg(bio, tg, &q->td->service_queue);
         throttled = true;
 
         if (update_disptime) {
-                tg_update_disptime(&td->service_queue, tg);
+                tg_update_disptime(tg, &td->service_queue);
                 throtl_schedule_next_dispatch(td);
         }
 
@@ -1132,7 +1134,7 @@ void blk_throtl_drain(struct request_queue *q)
         __releases(q->queue_lock) __acquires(q->queue_lock)
 {
         struct throtl_data *td = q->td;
-        struct throtl_service_queue *sq = &td->service_queue;
+        struct throtl_service_queue *parent_sq = &td->service_queue;
         struct throtl_grp *tg;
         struct bio_list bl;
         struct bio *bio;
@@ -1141,8 +1143,8 @@ void blk_throtl_drain(struct request_queue *q)
 
         bio_list_init(&bl);
 
-        while ((tg = throtl_rb_first(sq))) {
-                throtl_dequeue_tg(sq, tg);
+        while ((tg = throtl_rb_first(parent_sq))) {
+                throtl_dequeue_tg(tg, parent_sq);
 
                 while ((bio = bio_list_peek(&tg->bio_lists[READ])))
                         tg_dispatch_one_bio(tg, bio_data_dir(bio), &bl);