Merge branch 'writeback-workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq into for-3.10/core

Tejun writes:

-----

This is the pull request for the earlier patchset[1] with the same
name.  It's only three patches (the first one was committed to
workqueue tree) but the merge strategy is a bit involved due to the
dependencies.

* Because the conversion needs features from wq/for-3.10,
  block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts
  with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those
  workqueue conflicts from flaring up in block tree.

* Resolving the issue that Jan and Dave raised about debugging
  requires arch-wide changes.  The patchset is being worked on[2] but
  it'll have to go through -mm after these changes show up in -next,
  and not included in this pull request.

The three commits are located in the following git branch.

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue

Pulling it into block/for-3.10/core produces a conflict in
drivers/md/raid5.c between the following two commits.

  e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available")
  2f6db2a707 ("raid5: use bio_reset()")

The conflict is trivial - one removes an "if ()" conditional while the
other removes "rbi->bi_next = NULL" right above it.  We just need to
remove both.  The merged branch is available at

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge

so that you can use it for verification.  The test merge commit has
proper merge description.

While these changes are a bit of pain to route, they make code simpler
and even have, while minute, measureable performance gain[3] even on a
workload which isn't particularly favorable to showing the benefits of
this conversion.

----

Fixed up the conflict.

Conflicts:
	drivers/md/raid5.c

Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 17 insertions, 6 deletions

diff --git a/drivers/s390/block/scm_drv.c b/drivers/s390/block/scm_drv.c
index 9fa0a908607b..5f6180d6ff08 100644
--- a/drivers/s390/block/scm_drv.c
+++ b/drivers/s390/block/scm_drv.c
@@ -13,12 +13,23 @@
 #include <asm/eadm.h>
 #include "scm_blk.h"
 
-static void notify(struct scm_device *scmdev)
+static void scm_notify(struct scm_device *scmdev, enum scm_event event)
 {
-	pr_info("%lu: The capabilities of the SCM increment changed\n",
-		(unsigned long) scmdev->address);
-	SCM_LOG(2, "State changed");
-	SCM_LOG_STATE(2, scmdev);
+	struct scm_blk_dev *bdev = dev_get_drvdata(&scmdev->dev);
+
+	switch (event) {
+	case SCM_CHANGE:
+		pr_info("%lu: The capabilities of the SCM increment changed\n",
+			(unsigned long) scmdev->address);
+		SCM_LOG(2, "State changed");
+		SCM_LOG_STATE(2, scmdev);
+		break;
+	case SCM_AVAIL:
+		SCM_LOG(2, "Increment available");
+		SCM_LOG_STATE(2, scmdev);
+		scm_blk_set_available(bdev);
+		break;
+	}
 }
 
 static int scm_probe(struct scm_device *scmdev)
@@ -64,7 +75,7 @@ static struct scm_driver scm_drv = {
 		.name = "scm_block",
 		.owner = THIS_MODULE,
 	},
-	.notify = notify,
+	.notify = scm_notify,
 	.probe = scm_probe,
 	.remove = scm_remove,
 	.handler = scm_blk_irq,