sbitmap: add helpers for add/del wait queue handling
After commit 5d2ee7122c73, users of sbitmap that need wait queue
handling must use the provided helpers. But we only added
prepare_to_wait()/finish_wait() style helpers, add the equivalent
add_wait_queue/list_del wrappers as we..
This is needed to ensure kyber plays by the sbitmap waitqueue
rules.
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/lib/sbitmap.c b/lib/sbitmap.c
index 5b3e56d..65c2d06 100644
--- a/lib/sbitmap.c
+++ b/lib/sbitmap.c
@@ -671,13 +671,35 @@
}
EXPORT_SYMBOL_GPL(sbitmap_queue_show);
+void sbitmap_add_wait_queue(struct sbitmap_queue *sbq,
+ struct sbq_wait_state *ws,
+ struct sbq_wait *sbq_wait)
+{
+ if (!sbq_wait->sbq) {
+ sbq_wait->sbq = sbq;
+ atomic_inc(&sbq->ws_active);
+ }
+ add_wait_queue(&ws->wait, &sbq_wait->wait);
+}
+EXPORT_SYMBOL_GPL(sbitmap_add_wait_queue);
+
+void sbitmap_del_wait_queue(struct sbq_wait *sbq_wait)
+{
+ list_del_init(&sbq_wait->wait.entry);
+ if (sbq_wait->sbq) {
+ atomic_dec(&sbq_wait->sbq->ws_active);
+ sbq_wait->sbq = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(sbitmap_del_wait_queue);
+
void sbitmap_prepare_to_wait(struct sbitmap_queue *sbq,
struct sbq_wait_state *ws,
struct sbq_wait *sbq_wait, int state)
{
- if (!sbq_wait->accounted) {
+ if (!sbq_wait->sbq) {
atomic_inc(&sbq->ws_active);
- sbq_wait->accounted = 1;
+ sbq_wait->sbq = sbq;
}
prepare_to_wait_exclusive(&ws->wait, &sbq_wait->wait, state);
}
@@ -687,9 +709,9 @@
struct sbq_wait *sbq_wait)
{
finish_wait(&ws->wait, &sbq_wait->wait);
- if (sbq_wait->accounted) {
+ if (sbq_wait->sbq) {
atomic_dec(&sbq->ws_active);
- sbq_wait->accounted = 0;
+ sbq_wait->sbq = NULL;
}
}
EXPORT_SYMBOL_GPL(sbitmap_finish_wait);