From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 28 Feb 2013 20:52:24 +0000 (-0800)
Subject: Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block
X-Git-Tag: v3.9-rc1~44
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ee89f81252179dcbf6cd65bd48299f5e52292d88;p=profile%2Fcommon%2Fkernel-common.git

Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block

Pull block IO core bits from Jens Axboe:
 "Below are the core block IO bits for 3.9.  It was delayed a few days
  since my workstation kept crashing every 2-8h after pulling it into
  current -git, but turns out it is a bug in the new pstate code (divide
  by zero, will report separately).  In any case, it contains:

   - The big cfq/blkcg update from Tejun and and Vivek.

   - Additional block and writeback tracepoints from Tejun.

   - Improvement of the should sort (based on queues) logic in the plug
     flushing.

   - _io() variants of the wait_for_completion() interface, using
     io_schedule() instead of schedule() to contribute to io wait
     properly.

   - Various little fixes.

  You'll get two trivial merge conflicts, which should be easy enough to
  fix up"

Fix up the trivial conflicts due to hlist traversal cleanups (commit
b67bfe0d42ca: "hlist: drop the node parameter from iterators").

* 'for-3.9/core' of git://git.kernel.dk/linux-block: (39 commits)
  block: remove redundant check to bd_openers()
  block: use i_size_write() in bd_set_size()
  cfq: fix lock imbalance with failed allocations
  drivers/block/swim3.c: fix null pointer dereference
  block: don't select PERCPU_RWSEM
  block: account iowait time when waiting for completion of IO request
  sched: add wait_for_completion_io[_timeout]
  writeback: add more tracepoints
  block: add block_{touch|dirty}_buffer tracepoint
  buffer: make touch_buffer() an exported function
  block: add @req to bio_{front|back}_merge tracepoints
  block: add missing block_bio_complete() tracepoint
  block: Remove should_sort judgement when flush blk_plug
  block,elevator: use new hashtable implementation
  cfq-iosched: add hierarchical cfq_group statistics
  cfq-iosched: collect stats from dead cfqgs
  cfq-iosched: separate out cfqg_stats_reset() from cfq_pd_reset_stats()
  blkcg: make blkcg_print_blkgs() grab q locks instead of blkcg lock
  block: RCU free request_queue
  blkcg: implement blkg_[rw]stat_recursive_sum() and blkg_[rw]stat_merge()
  ...
---

ee89f81252179dcbf6cd65bd48299f5e52292d88
diff --cc block/blk-cgroup.c
index 8bdebb6,87ea95d..b2b9837
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@@ -414,13 -518,17 +517,16 @@@ void blkcg_print_blkgs(struct seq_file 
  		       bool show_total)
  {
  	struct blkcg_gq *blkg;
 -	struct hlist_node *n;
  	u64 total = 0;
  
- 	spin_lock_irq(&blkcg->lock);
- 	hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node)
+ 	rcu_read_lock();
 -	hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {
++	hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) {
+ 		spin_lock_irq(blkg->q->queue_lock);
  		if (blkcg_policy_enabled(blkg->q, pol))
  			total += prfill(sf, blkg->pd[pol->plid], data);
- 	spin_unlock_irq(&blkcg->lock);
+ 		spin_unlock_irq(blkg->q->queue_lock);
+ 	}
+ 	rcu_read_unlock();
  
  	if (show_total)
  		seq_printf(sf, "Total %llu\n", (unsigned long long)total);
diff --cc block/cfq-iosched.c
index ec52807,1bf9307..4f0ade7
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@@ -1440,13 -1703,25 +1702,25 @@@ static int __cfq_set_weight(struct cgro
  		return -EINVAL;
  
  	spin_lock_irq(&blkcg->lock);
- 	blkcg->cfq_weight = (unsigned int)val;
+ 
+ 	if (!is_leaf_weight)
+ 		blkcg->cfq_weight = val;
+ 	else
+ 		blkcg->cfq_leaf_weight = val;
  
 -	hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
 +	hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node) {
  		struct cfq_group *cfqg = blkg_to_cfqg(blkg);
  
- 		if (cfqg && !cfqg->dev_weight)
- 			cfqg->new_weight = blkcg->cfq_weight;
+ 		if (!cfqg)
+ 			continue;
+ 
+ 		if (!is_leaf_weight) {
+ 			if (!cfqg->dev_weight)
+ 				cfqg->new_weight = blkcg->cfq_weight;
+ 		} else {
+ 			if (!cfqg->dev_leaf_weight)
+ 				cfqg->new_leaf_weight = blkcg->cfq_leaf_weight;
+ 		}
  	}
  
  	spin_unlock_irq(&blkcg->lock);
diff --cc block/elevator.c
index d0acb31,11683bb..a0ffdd9
--- a/block/elevator.c
+++ b/block/elevator.c
@@@ -287,11 -252,10 +273,10 @@@ static void elv_rqhash_reposition(struc
  static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset)
  {
  	struct elevator_queue *e = q->elevator;
- 	struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)];
 -	struct hlist_node *entry, *next;
 +	struct hlist_node *next;
  	struct request *rq;
  
- 	hlist_for_each_entry_safe(rq, next, hash_list, hash) {
 -	hash_for_each_possible_safe(e->hash, rq, entry, next, hash, offset) {
++	hash_for_each_possible_safe(e->hash, rq, next, hash, offset) {
  		BUG_ON(!ELV_ON_HASH(rq));
  
  		if (unlikely(!rq_mergeable(rq))) {