[PATCH] io_uring: use correct "is IO worker" helper

[PATCH] io_uring: use correct "is IO worker" helper

[Jens Axboe]

Since we switched to io-wq, the dependent link optimization for when to
pass back work inline has been broken. Fix this by providing a suitable
io-wq helper for io_uring to use to detect when to do this.

Fixes: 561fb04a6a22 ("io_uring: replace workqueue usage with io-wq")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

---

diff --git a/fs/io-wq.h b/fs/io-wq.h
index 8cb345256f35..cc50754d028c 100644
--- a/fs/io-wq.h
+++ b/fs/io-wq.h
@@ -62,4 +62,8 @@ static inline void io_wq_worker_running(struct task_struct *tsk)
 }
 #endif
 
+static inline bool io_wq_current_is_worker(void)
+{
+	return in_task() && (current->flags & PF_IO_WORKER);
+}
 #endif
diff --git a/fs/io_uring.c b/fs/io_uring.c
index a0a69f115677..a37daa0e9893 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -871,7 +871,7 @@ static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr)
 			/* we dropped this link, get next */
 			nxt = list_first_entry_or_null(&req->link_list,
 							struct io_kiocb, list);
-		} else if (nxtptr && current_work()) {
+		} else if (nxtptr && io_wq_current_is_worker()) {
 			*nxtptr = nxt;
 			break;
 		} else {

-- 
Jens Axboe