bcache: Convert gc to a kthread
We needed a dedicated rescuer workqueue for gc anyways... and gc was
conceptually a dedicated thread, just one that wasn't running all the
time. Switch it to a dedicated thread to make the code a bit more
straightforward.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index d352074..09410eb 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -773,7 +773,7 @@
struct gc_stat gc_stats;
size_t nbuckets;
- struct closure_with_waitlist gc;
+ struct task_struct *gc_thread;
/* Where in the btree gc currently is */
struct bkey gc_done;
@@ -786,11 +786,10 @@
/* Counts how many sectors bio_insert has added to the cache */
atomic_t sectors_to_gc;
- struct closure moving_gc;
- struct closure_waitlist moving_gc_wait;
+ wait_queue_head_t moving_gc_wait;
struct keybuf moving_gc_keys;
/* Number of moving GC bios in flight */
- atomic_t in_flight;
+ struct semaphore moving_in_flight;
struct btree *root;
@@ -1176,7 +1175,7 @@
void bch_prio_write(struct cache *);
void bch_write_bdev_super(struct cached_dev *, struct closure *);
-extern struct workqueue_struct *bcache_wq, *bch_gc_wq;
+extern struct workqueue_struct *bcache_wq;
extern const char * const bch_cache_modes[];
extern struct mutex bch_register_lock;
extern struct list_head bch_cache_sets;