[RFC 1/2] io_uring: add tw add flags

[Pavel Begunkov <asml.silence@gmail.com>]

We pass 'allow_local' into io_req_task_work_add() but will need more
flags. Replace it with a flags bit field and name this allow_local
flag.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 io_uring/io_uring.c | 7 ++++---
 io_uring/io_uring.h | 9 +++++++--
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 7625597b5227..42ada470845f 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1308,12 +1308,13 @@ static void io_req_local_work_add(struct io_kiocb *req)
 	percpu_ref_put(&ctx->refs);
 }
 
-void __io_req_task_work_add(struct io_kiocb *req, bool allow_local)
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags)
 {
 	struct io_uring_task *tctx = req->task->io_uring;
 	struct io_ring_ctx *ctx = req->ctx;
 
-	if (allow_local && ctx->flags & IORING_SETUP_DEFER_TASKRUN) {
+	if (!(flags & IOU_F_TWQ_FORCE_NORMAL) &&
+	    (ctx->flags & IORING_SETUP_DEFER_TASKRUN)) {
 		io_req_local_work_add(req);
 		return;
 	}
@@ -1341,7 +1342,7 @@ static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx)
 						    io_task_work.node);
 
 		node = node->next;
-		__io_req_task_work_add(req, false);
+		__io_req_task_work_add(req, IOU_F_TWQ_FORCE_NORMAL);
 	}
 }
 
diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index 2711865f1e19..cd2e702f206c 100644
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -15,6 +15,11 @@
 #include <trace/events/io_uring.h>
 #endif
 
+enum {
+	/* don't use deferred task_work */
+	IOU_F_TWQ_FORCE_NORMAL			= 1,
+};
+
 enum {
 	IOU_OK			= 0,
 	IOU_ISSUE_SKIP_COMPLETE	= -EIOCBQUEUED,
@@ -48,7 +53,7 @@ static inline bool io_req_ffs_set(struct io_kiocb *req)
 	return req->flags & REQ_F_FIXED_FILE;
 }
 
-void __io_req_task_work_add(struct io_kiocb *req, bool allow_local);
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
 bool io_is_uring_fops(struct file *file);
 bool io_alloc_async_data(struct io_kiocb *req);
 void io_req_task_queue(struct io_kiocb *req);
@@ -93,7 +98,7 @@ bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
 
 static inline void io_req_task_work_add(struct io_kiocb *req)
 {
-	__io_req_task_work_add(req, true);
+	__io_req_task_work_add(req, 0);
 }
 
 #define io_for_each_link(pos, head) \
-- 
2.39.1