block: remove per-queue plugging
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 924f5f0..400cf35 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -37,13 +37,6 @@
unsigned int nr_pages;
unsigned int nr_free_pages;
- /*
- * Block devices to unplug.
- * Non-NULL pointer means that a block device has some pending requests
- * and needs to be unplugged.
- */
- struct block_device *unplug[2];
-
struct dm_io_client *io_client;
wait_queue_head_t destroyq;
@@ -315,31 +308,6 @@
return 0;
}
-/*
- * Unplug the block device at the specified index.
- */
-static void unplug(struct dm_kcopyd_client *kc, int rw)
-{
- if (kc->unplug[rw] != NULL) {
- blk_unplug(bdev_get_queue(kc->unplug[rw]));
- kc->unplug[rw] = NULL;
- }
-}
-
-/*
- * Prepare block device unplug. If there's another device
- * to be unplugged at the same array index, we unplug that
- * device first.
- */
-static void prepare_unplug(struct dm_kcopyd_client *kc, int rw,
- struct block_device *bdev)
-{
- if (likely(kc->unplug[rw] == bdev))
- return;
- unplug(kc, rw);
- kc->unplug[rw] = bdev;
-}
-
static void complete_io(unsigned long error, void *context)
{
struct kcopyd_job *job = (struct kcopyd_job *) context;
@@ -386,15 +354,12 @@
.client = job->kc->io_client,
};
- if (job->rw == READ) {
+ if (job->rw == READ)
r = dm_io(&io_req, 1, &job->source, NULL);
- prepare_unplug(job->kc, READ, job->source.bdev);
- } else {
+ else {
if (job->num_dests > 1)
io_req.bi_rw |= REQ_UNPLUG;
r = dm_io(&io_req, job->num_dests, job->dests, NULL);
- if (!(io_req.bi_rw & REQ_UNPLUG))
- prepare_unplug(job->kc, WRITE, job->dests[0].bdev);
}
return r;
@@ -466,6 +431,7 @@
{
struct dm_kcopyd_client *kc = container_of(work,
struct dm_kcopyd_client, kcopyd_work);
+ struct blk_plug plug;
/*
* The order that these are called is *very* important.
@@ -473,18 +439,12 @@
* Pages jobs when successful will jump onto the io jobs
* list. io jobs call wake when they complete and it all
* starts again.
- *
- * Note that io_jobs add block devices to the unplug array,
- * this array is cleared with "unplug" calls. It is thus
- * forbidden to run complete_jobs after io_jobs and before
- * unplug because the block device could be destroyed in
- * job completion callback.
*/
+ blk_start_plug(&plug);
process_jobs(&kc->complete_jobs, kc, run_complete_job);
process_jobs(&kc->pages_jobs, kc, run_pages_job);
process_jobs(&kc->io_jobs, kc, run_io_job);
- unplug(kc, READ);
- unplug(kc, WRITE);
+ blk_finish_plug(&plug);
}
/*
@@ -665,8 +625,6 @@
INIT_LIST_HEAD(&kc->io_jobs);
INIT_LIST_HEAD(&kc->pages_jobs);
- memset(kc->unplug, 0, sizeof(kc->unplug));
-
kc->job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache);
if (!kc->job_pool)
goto bad_slab;