bcache: initialize dirty stripes in flash_dev_run()
bcache uses a Proportion-Differentiation Controller algorithm to control
writeback rate to cached devices. In the PD controller algorithm, dirty
stripes of thin flash device should not be counted in, because flash only
volumes never write back dirty data.
Currently dirty stripe counter for thin flash device is not initialized
when the thin flash device starts. Which means the following calculation
in PD controller will reference an undefined dirty stripes number, and
all cached devices attached to the same cache set where the thin flash
device lies on may have an inaccurate writeback rate.
This patch calles bch_sectors_dirty_init() in flash_dev_run(), to
correctly initialize dirty stripe counter when the thin flash device
starts to run. This patch also does following parameter data type change,
-void bch_sectors_dirty_init(struct cached_dev *dc);
+void bch_sectors_dirty_init(struct bcache_device *);
to call this function conveniently in flash_dev_run().
(Commit log is composed by Coly Li)
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 1ae6337..fc0a31b 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1026,7 +1026,7 @@
}
if (BDEV_STATE(&dc->sb) == BDEV_STATE_DIRTY) {
- bch_sectors_dirty_init(dc);
+ bch_sectors_dirty_init(&dc->disk);
atomic_set(&dc->has_dirty, 1);
atomic_inc(&dc->count);
bch_writeback_queue(dc);
@@ -1230,6 +1230,7 @@
goto err;
bcache_device_attach(d, c, u - c->uuids);
+ bch_sectors_dirty_init(d);
bch_flash_dev_request_init(d);
add_disk(d->disk);
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index 3413143..e663ca0 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -482,17 +482,17 @@
return MAP_CONTINUE;
}
-void bch_sectors_dirty_init(struct cached_dev *dc)
+void bch_sectors_dirty_init(struct bcache_device *d)
{
struct sectors_dirty_init op;
bch_btree_op_init(&op.op, -1);
- op.inode = dc->disk.id;
+ op.inode = d->id;
- bch_btree_map_keys(&op.op, dc->disk.c, &KEY(op.inode, 0, 0),
+ bch_btree_map_keys(&op.op, d->c, &KEY(op.inode, 0, 0),
sectors_dirty_init_fn, 0);
- dc->disk.sectors_dirty_last = bcache_dev_sectors_dirty(&dc->disk);
+ d->sectors_dirty_last = bcache_dev_sectors_dirty(d);
}
void bch_cached_dev_writeback_init(struct cached_dev *dc)
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h
index 8789b9c..e35421d 100644
--- a/drivers/md/bcache/writeback.h
+++ b/drivers/md/bcache/writeback.h
@@ -103,7 +103,7 @@
void bcache_dev_sectors_dirty_add(struct cache_set *, unsigned, uint64_t, int);
-void bch_sectors_dirty_init(struct cached_dev *dc);
+void bch_sectors_dirty_init(struct bcache_device *);
void bch_cached_dev_writeback_init(struct cached_dev *);
int bch_cached_dev_writeback_start(struct cached_dev *);