1 files changed, 19 insertions, 14 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 7c52d6888924..ae21919f15e1 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -185,7 +185,7 @@ struct cfq_group {
 	int nr_cfqq;
 
 	/*
-	 * Per group busy queus average. Useful for workload slice calc. We
+	 * Per group busy queues average. Useful for workload slice calc. We
 	 * create the array for each prio class but at run time it is used
 	 * only for RT and BE class and slot for IDLE class remains unused.
 	 * This is primarily done to avoid confusion and a gcc warning.
@@ -369,16 +369,16 @@ CFQ_CFQQ_FNS(wait_busy);
 #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', \
-			blkg_path(&(cfqq)->cfqg->blkg), ##args);
+			blkg_path(&(cfqq)->cfqg->blkg), ##args)
 
 #define cfq_log_cfqg(cfqd, cfqg, fmt, args...)				\
 	blk_add_trace_msg((cfqd)->queue, "%s " fmt,			\
-				blkg_path(&(cfqg)->blkg), ##args);      \
+				blkg_path(&(cfqg)->blkg), ##args)       \
 
 #else
 #define cfq_log_cfqq(cfqd, cfqq, fmt, args...)	\
 	blk_add_trace_msg((cfqd)->queue, "cfq%d " fmt, (cfqq)->pid, ##args)
-#define cfq_log_cfqg(cfqd, cfqg, fmt, args...)		do {} while (0);
+#define cfq_log_cfqg(cfqd, cfqg, fmt, args...)		do {} while (0)
 #endif
 #define cfq_log(cfqd, fmt, args...)	\
 	blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args)
@@ -988,9 +988,10 @@ 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);
-	cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u disp=%u charge=%u iops=%u"
-			" sect=%u", used_sl, cfqq->slice_dispatch, charge,
-			iops_mode(cfqd), cfqq->nr_sectors);
+	cfq_log_cfqq(cfqq->cfqd, cfqq,
+		     "sl_used=%u disp=%u charge=%u iops=%u sect=%lu",
+		     used_sl, cfqq->slice_dispatch, charge,
+		     iops_mode(cfqd), cfqq->nr_sectors);
 	cfq_blkiocg_update_timeslice_used(&cfqg->blkg, used_sl,
 					  unaccounted_sl);
 	cfq_blkiocg_set_start_empty_time(&cfqg->blkg);
@@ -2023,8 +2024,8 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
 	 */
 	if (sample_valid(cic->ttime_samples) &&
 	    (cfqq->slice_end - jiffies < cic->ttime_mean)) {
-		cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%d",
-				cic->ttime_mean);
+		cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%lu",
+			     cic->ttime_mean);
 		return;
 	}
 
@@ -2772,8 +2773,14 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
 	smp_wmb();
 	cic->key = cfqd_dead_key(cfqd);
 
-	if (ioc->ioc_data == cic)
+	rcu_read_lock();
+	if (rcu_dereference(ioc->ioc_data) == cic) {
+		rcu_read_unlock();
+		spin_lock(&ioc->lock);
 		rcu_assign_pointer(ioc->ioc_data, NULL);
+		spin_unlock(&ioc->lock);
+	} else
+		rcu_read_unlock();
 
 	if (cic->cfqq[BLK_RW_ASYNC]) {
 		cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]);
@@ -3080,7 +3087,8 @@ cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc,
 
 	spin_lock_irqsave(&ioc->lock, flags);
 
-	BUG_ON(ioc->ioc_data == cic);
+	BUG_ON(rcu_dereference_check(ioc->ioc_data,
+		lockdep_is_held(&ioc->lock)) == cic);
 
 	radix_tree_delete(&ioc->radix_root, cfqd->cic_index);
 	hlist_del_rcu(&cic->cic_list);
@@ -3786,9 +3794,6 @@ new_queue:
 	return 0;
 
 queue_fail:
-	if (cic)
-		put_io_context(cic->ioc);
-
 	cfq_schedule_dispatch(cfqd);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 	cfq_log(cfqd, "set_request fail");