bcache: Allocation kthread fixes
The alloc kthread should've been using try_to_freeze() - and also there
was the potential for the alloc kthread to get woken up after it had
shut down, which would have been bad.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index b54b73b..e45f557 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -63,6 +63,7 @@
#include "bcache.h"
#include "btree.h"
+#include <linux/freezer.h>
#include <linux/kthread.h>
#include <linux/random.h>
#include <trace/events/bcache.h>
@@ -363,11 +364,10 @@
break; \
\
mutex_unlock(&(ca)->set->bucket_lock); \
- if (test_bit(CACHE_SET_STOPPING_2, &ca->set->flags)) { \
- closure_put(&ca->set->cl); \
+ if (kthread_should_stop()) \
return 0; \
- } \
\
+ try_to_freeze(); \
schedule(); \
mutex_lock(&(ca)->set->bucket_lock); \
} \
@@ -547,14 +547,12 @@
int bch_cache_allocator_start(struct cache *ca)
{
- ca->alloc_thread = kthread_create(bch_allocator_thread,
- ca, "bcache_allocator");
- if (IS_ERR(ca->alloc_thread))
- return PTR_ERR(ca->alloc_thread);
+ struct task_struct *k = kthread_run(bch_allocator_thread,
+ ca, "bcache_allocator");
+ if (IS_ERR(k))
+ return PTR_ERR(k);
- closure_get(&ca->set->cl);
- wake_up_process(ca->alloc_thread);
-
+ ca->alloc_thread = k;
return 0;
}